JP2004141619A - Absorptive article - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an absorptive article capable of absorbing liquids promptly in a limited central range of the absorptive article, preventing the liquids from diffusing in a surface sheet, moreover, quickly absorbing the liquids leaked out to the side. <P>SOLUTION: A central absorption region 11 with a fixed area is provided in a range which is surrounded by a contact bonded part 9. In this central absorption region 11, a liquid guide layer 5 which becomes three-dimensional skeleton structure with a chemical fiber is laid on a lower layer absorption body 3 and an upper layer absorption body 4, and this liquid guide layer 5 is formed by size which is not taken for the contact bonded part 9. In this part, the liquid guide layer 5 shows a function to lead the liquid to the absorption layer, and the liquid is quickly absorbed like a spot by the central part in the central absorption area 11. An auxiliary absorption area 12 where an absorption layer is covered up with a surface sheet 6 is provided at the outer peripheral part of the contact bonded part 9, and the liquids which adheres to this part is also promptly absorbed. <P>COPYRIGHT: (C)2004,JPO

Description

【０２１２】
次に、表１に示した各条件下の厚みと、それぞれのサンプルのエアースルー不織布の目付けとから、密度を換算した。表２に、前記乾燥時の密度、湿潤時の密度、および湿潤状態で加圧時の密度を示す。
【０２１３】
【表２】

【０２１４】
（１２）液拡散試験
上記実施例１ないし６および比較例１ないし４のそれぞれのエアースルー不織布を、１００×１００ｍｍの大きさとして、これを３枚重ねたものを測定用の液案内層とした。
【０２１５】
測定用の表面シートとして、芯部が酸化チタンを繊維の質量の１．１質量％含有したポリエチレンテレフタレート（ＰＥＴ）で鞘部がポリエチレン（ＰＥ）の偏芯タイプの芯鞘型複合合成繊維で繊度が２．２ｄｔｅｘ、繊維長が４４ｍｍを用いて、目付けが２５ｇ／ｍ^２のエアースルー不織布を使用した。前記表面シートを、幅寸法１００ｍｍ、長さ寸法を２００ｍｍにカットした。
【０２１６】
測定用の吸収層として、化学パルプを目付け１６０ｇ／ｍ^２と高吸収性ポリマーを８ｇ／ｍ^２混合したもので、縦寸法が１８０ｍｍ、幅寸法が７５ｍｍの下層吸収体と、化学パルプの積層体で目付けが２３０ｇ／ｍ^２、縦寸法が１２０ｍｍ、幅寸法が５５ｍｍの下層吸収体を用いた。下層吸収体の上に上層吸収体を重ね、上下を目付けが１５ｇ／ｍ^２のティッシュでサンドした。
【０２１７】
幅寸法が１００ｍｍ、長さ寸法が２００ｍｍのアクリル板の上に、前記吸収層と、前記液案内層と、前記表面シートを重ねる。質量１１５ｇで幅寸法１００ｍｍ、縦方向の長さ寸法２００ｍｍのアクリル板の中央部に幅１０ｍｍ、縦方向の長さ４０ｍｍの長穴を形成して、これを前記表面シートの上に載せ、前記長穴がサンプルの中央に位置するように設定した。
【０２１８】
前記長穴から前記人口経血を供給した。注入速度を９５ｍｌ／ｍｉｎとし、１回目に３ｍｌを供給し、サンプル表面から液が無くなった後の３０秒に、同じ注入速度で２回目は４ｍｌを供給し、表面から液が無くなった後の３０秒後に、同じ注入速度で３回目は３ｍｌ供給した。
【０２１９】
３回目の注入の後に、サンプル表面から液が無くなったことを確認してから１ｍｉｎ後に長穴を有するアクリル板を外し、表面シートでの横方向への液の拡散寸法を測定した。この拡散寸法は、縦方向と横方向とで最も長い距離とした。
測定結果を表３に示す。
【０２２０】
【表３】

【０２２１】
表１に示すように、実施例１ないし６の液案内層はいずれも湿潤状態での１枚の不織布の加圧厚みが０．５ｍｍ以上で１ｍｍ以下であり、圧力を取り除いた後の１枚の不織布の復元厚みは１ｍｍ以上で２ｍｍ以下である。よって、この不織布を３枚重ねで拡散状態を測定したため、湿潤状態の液案内層の厚みは１．５〜３ｍｍであり、前記復元厚みは３〜６ｍｍである。また実施例の乾燥時の密度は、０．００５〜０．０２ｇ／ｃｍ^３であり、湿潤時で且つ加圧時の密度は、０．００５ｇ／ｃｍ^３〜０．０４ｇ／ｃｍ^３である。
【０２２２】
【発明の効果】
以上のように本発明では、吸収性物品の中央部分の限られた範囲で繰り返して与えられる液体を迅速に引き込むことができ、表面シートでの液の拡散を防止でき、また側方への液体の移行があったとしてもこれを迅速に吸収でき、横漏れを有効に防止できる。特に、本発明は、中央部分が身体の排泄部に密着できる構造となり、身体への装着感触が良好であり、また中央部分で集中して液体を吸収できるものとなる。
【図面の簡単な説明】
【図１】本発明の吸収性物品の第１の実施の形態の生理用ナプキンを示す斜視図、
【図２】図１に示す生理用ナプキンの平面図、
【図３】図１と図２に示す生理用ナプキンの横方向中心線での断面図、
【図４】（Ａ）は図３に示す断面図の中央吸収領域の拡大図、（Ｂ）は補助吸収領域の拡大図、
【図５】生理用ナプキンが身体に着用されたときの変形状態を示す断面図、
【図６】液透過孔の開孔状態を示す拡大平面図、
【図７】第２の実施の形態の生理用ナプキンを示す平面図、
【図８】第３の実施の形態の生理用ナプキンを示す平面図、
【図９】第４の実施の形態のウイング部を有する生理用ナプキンを示す平面図、
【図１０】第５の実施の形態の生理用ナプキンを示す平面図、
【図１１】第６の実施の形態の生理用ナプキンを示す平面図、
【図１２】（Ａ）（Ｂ）は、防漏壁が設けられた生理用ナプキンの半断面図、
【図１３】本発明の生理用ナプキンの製造方法の一例を示す工程説明図、
【図１４】加熱ユニットの他の例を示す説明図、
【図１５】加熱ユニットの他の例を示す説明図、
【図１６】加熱ユニットの他の例を示す説明図、
【符号の説明】
１、１Ａ、１Ｂ、１Ｃ、１Ｄ、１Ｅ　生理用ナプキン
２　裏面シート
３　下層吸収体
４　上層吸収体
５　液案内層
６　表面シート
９，９０，１９０　圧着部
９ａ　右側圧着部
９ｂ　左側圧着部
９ｃ　前方圧着部
９ｄ　後方圧着部
９ｅ，９ｆ　前方延長圧着部
９ｇ，９ｈ　後方延長圧着部
１１，１１Ａ，１１Ｂ　中央吸収領域
１２，１２Ａ，１２Ｂ　補助吸収領域
１５　液透過孔
１０２　第１の駆動ロール
１０３　第２の駆動ロール
１０３，１４６　加熱ユニット
１０４　嵩回復のための加熱装置
１０７　冷却装置
１４２，１４３　嵩回復のための加熱ロール[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an absorbent article suitable for absorbing menstrual blood and vaginal discharge excreted from female genital organs, and in particular, a liquid having a relatively high viscosity given to a topsheet is quickly drawn into an absorbent layer, and The present invention relates to an absorbent article capable of narrowing a diffusion range.
[0002]
[Prior art]
The general structure of an absorbent article that absorbs menstrual blood excreted from female genitals is such that the surface of the absorbent layer is covered with a liquid-permeable top sheet. The absorbent layer is formed of a mixture of hydrophilic fibers such as pulp and a superabsorbent polymer (SAP), and the topsheet is formed of a nonwoven fabric or a rayon made of hydrophilic chemically treated hydrophobic chemical fibers. Nonwoven fabrics formed of hydrophilic fibers such as those described above are used.
[0003]
In this absorbent article, a relatively high-density absorbent layer formed of hydrophilic fibers is located immediately below the topsheet. The liquid applied to the surface of the topsheet is attracted by the hydrophilicity and the capillary action of the absorption layer, quickly penetrates the topsheet, is absorbed and held by the absorption layer.
[0004]
However, menstrual blood at the time of menstruation of a woman has a relatively high viscosity and is continuously excreted, so that the liquid easily saturates in the topsheet when the absorbent layer holds a certain amount of liquid. In other words, menstrual blood quickly penetrates the topsheet by its own weight, but since the rate of absorption of the liquid by the capillary action of the absorbent layer is slightly lower than this permeation rate, a large amount of liquid is given in a short time. Then, the liquid cannot be completely absorbed by the absorbing layer, and the liquid tends to remain in the topsheet. Since this liquid diffuses around the inside of the topsheet, a wide area of the topsheet is wetted by menstrual blood, giving a feeling of moisturization to the skin, and by spreading the menstrual diffusion area on the surface, There is a fear of giving the wearer visual disgust.
[0005]
On the other hand, Patent Document 1 listed below discloses a second sheet having a lower density than a surface sheet between an absorbent layer formed of a mixture of flocculent pulp and a super absorbent polymer and a liquid permeable surface sheet. Is disclosed, and this second sheet is formed by bonding hydrophilically-treated composite fibers.
[0006]
An object of the invention described in this publication is to make it difficult for body fluid to stay in the topsheet and the second sheet by spot-absorbing the liquid given to the topsheet and reaching the absorption layer by the second sheet.
[0007]
[Patent Document 1]
JP-A-11-192259
[0008]
[Problems to be solved by the invention]
However, the liquid that has passed through the top sheet and reached the second sheet cannot be prevented from diffusing to the surroundings along the second sheet. In the absorbent article described in the above publication, the area of the second sheet is not particularly limited. Therefore, when the liquid is diffused along the second sheet, the liquid is likely to be diffused also in the top sheet.
[0009]
In addition, the one described in the above publication has a flat structure as a whole, so that the liquid permeated through the second sheet and absorbed by the absorption layer will diffuse widely in the high-density absorption layer, Even in the outer peripheral region deviating from the second sheet, a large amount of liquid is likely to be present in the absorbing layer. In this outer peripheral region, the topsheet is directly located on the surface of the absorption layer, and therefore, in the outer peripheral region, the topsheet is easily saturated with liquid at an early stage after the start of use. Therefore, the topsheet becomes wet in a wide range, and it is easy to give a sense of humidity to the body, and the liquid transmitted on the surface of the topsheet is likely to cause lateral leakage.
[0010]
Further, in the manufacturing process of the absorbent article, a raw material wound with a band-shaped nonwoven fabric for forming a second sheet is used, and the nonwoven fabric drawn from the raw material is cut so as to have a predetermined area. Is generally used as the second sheet.
[0011]
However, since the bulk (thickness) of the non-woven fabric rolled is crushed by the wrapping pressure and stored in that state, the non-woven fabric pulled out of the raw fabric is in a state where the bulk remains crushed. It has become. When the second sheet is formed by the nonwoven fabric, the second sheet has a relatively low density and a relatively high density in which internal voids are crushed.
[0012]
Therefore, the speed at which the liquid that has passed through the topsheet is drawn into the second sheet is reduced, and the liquid tends to stay in the topsheet. Furthermore, before the liquid drawn into the second sheet is absorbed by the absorbent layer, the liquid spreads through the second sheet having a relatively high density and diffuses around, so that the liquid stays in the second sheet in a wide range, As a result, the liquid easily returns to the topsheet.
[0013]
In addition, there is also a problem that a soft seating feeling cannot be given to a bulky second seat.
[0014]
The present invention has been made to solve the above-mentioned conventional problems, and enables a liquid repeatedly supplied within a limited area to be rapidly absorbed, and a liquid that has reached an outer peripheral area to be always rapidly absorbed, so that the It is an object of the present invention to provide an absorbent article that can suppress a liquid diffusion range in a sheet and easily prevent lateral leakage.
[0015]
[Means for Solving the Problems]
The present invention provides an absorbent article in which an absorbent layer is provided between a back sheet and a liquid-permeable top sheet,
At a position separated from the center line extending in the vertical direction by a predetermined distance on both the left and right sides, a crimping portion in which the topsheet and the absorbent layer are pressed in a concave shape is formed continuously in the vertical direction, and is sandwiched by the crimping portions. The inner side is divided into a central absorption region and an outer peripheral side beyond the crimping portion is an auxiliary absorption region,
In the central absorption region, between the absorption layer having a hydrophilic material and the topsheet, a liquid guide layer having a structure in which fibers are joined to form a void and having a lower density than the absorption layer is provided. Provided, the liquid guide layer is formed in a size that does not hang on the crimping portion,
In the auxiliary absorption region, the absorption layer is covered with the topsheet.
[0016]
In the absorbent article according to the present invention, the central absorbent area and the auxiliary absorbent area on the outer peripheral side thereof are divided by the crimping part by embossing, and the liquid given to the top sheet in the central absorbent area is a liquid guide having a low density. By entering into the space of the layer by its own weight, it is absorbed by the liquid guiding layer, and the liquid in the liquid guiding layer is attracted to the hydrophilic action and the capillary action of the underlying absorbing layer, and is absorbed by the absorbing layer. Will be retained. Therefore, when the liquid is repeatedly supplied to the central absorption region, the liquid is transferred to the liquid guide layer, so that the liquid can be prevented from staying in the topsheet, and the topsheet can always maintain a state in which the liquid easily permeates. In addition, since the liquid guide layer is provided only in a limited range in the central absorption region, the liquid that is repeatedly provided mainly passes through the limited range in the central absorption region, Diffusion of the liquid on the topsheet can be suppressed, and spot absorption of the liquid can be made possible. In addition, the liquid that is absorbed by the absorbing layer and tries to diffuse to the side is blocked by the pressure-bonding portion, so that the liquid hardly moves to the absorbing layer in the auxiliary absorption region. Therefore, in the auxiliary absorption region, the topsheet is less likely to be in a liquid saturated state, and the liquid adhering to the auxiliary absorption region is always drawn into the absorption layer located immediately below. Therefore, the diffusion of the liquid on the topsheet can be limited to a limited area within the central absorption area, making it difficult to give a feeling of moistness to the skin, and maintaining a state where the auxiliary absorption area can always rapidly absorb the liquid. Therefore, it is easy to prevent lateral leakage of the liquid.
[0017]
Preferably, the pressure-bonding portion is formed continuously so as to surround a predetermined range, a region surrounded by the pressure-bonding portion is the central absorption region, and the liquid guide layer is provided at the center. It can be configured such that it has an area smaller than the area of the absorption region, and any edge thereof is located at a position that does not cover the crimping portion.
[0018]
As described above, by setting the region surrounded by the compression portion as the central absorption region, the transmission region of the liquid that is repeatedly supplied can be limited to the range surrounded by the compression portion.
[0019]
In addition, the absorption layer has a lower absorber and an upper absorber having a smaller area than the lower absorber and having a larger area than the central absorption region, the upper absorber being overlaid on the lower absorber. In the crimping portion, the top sheet, the lower layer absorber and the upper layer absorber are pressed in a concave shape,
In the auxiliary absorption region, a bulky portion provided with both the lower absorber and the upper absorber is formed in a portion adjacent to the pressure-bonded portion, and a thickness having the lower absorber outside the bulky portion is formed. It is possible that a small area is formed.
[0020]
In this structure, not only the central absorption region but also the region immediately outside the crimping portion is bulky, so that the bulky region corresponding to the crotch portion can be widened and the wearing feeling is good. Further, since the absorption layer is thick in the auxiliary absorption region just outside the crimping portion, even if a large amount of liquid leaks to the outside of the crimping portion, the liquid can be quickly absorbed.
[0021]
Further, in the central absorption region, it is preferable that a large number of liquid permeable holes are formed from the top sheet to the liquid guide layer, and furthermore, a chemical fiber forming the top sheet around the liquid permeable holes. It is preferred that the chemical fiber forming the liquid guide layer is heat-sealed.
[0022]
When the liquid permeation hole is formed from the top sheet to the liquid guide layer, the liquid given to the top sheet in the central absorption region easily permeates in the region where the liquid guide layer is provided.
[0023]
Further, in order to allow the liquid repeatedly supplied to permeate the top sheet quickly as described above, the fiber density of the liquid guide layer at the time of drying is 0.005 g / cm. ³ 0.02 g / cm ³ The following is preferred.
[0024]
The liquid guide layer is 980 Pa (10 g / cm) in a wet state. ² ) Is 0.005 g / cm when the pressure is applied. ³ ~ 0.04g / cm ³ Is more preferably within the range.
[0025]
By carrying out heat treatment after the liquid guide layer is drawn out of the raw material, the bulk can be recovered and the density can be adjusted to the above-mentioned density range. When the density is within the above range, the porosity can be increased even when the liquid guide layer receives a pressing force from the body, and the bulk of the liquid guide layer is easily restored when the pressing force is released. The second sheet having the above-mentioned density allows the liquid repeatedly absorbed from the topsheet to pass through by its own weight, and can hold the liquid in the voids until it is absorbed by the absorbing layer. Therefore, the surface sheet is in a wet state, and it is easy to prevent the liquid from diffusing in a wide range in the surface sheet. Further, since the liquid guide layer functions as a cushion layer that relieves the contact pressure with the skin together with the top sheet, the soft feeling is increased and the wearing feeling can be improved.
[0026]
For example, the liquid guide layer is an air-through nonwoven fabric formed of chemical fibers or an air-laid nonwoven fabric containing chemical fibers.
[0027]
Further, the liquid guide layer may be formed by folding the nonwoven fabric such that a plurality of the nonwoven fabrics are stacked.
[0028]
When the liquid guide layer is formed by folding the nonwoven fabric in this manner, the central absorbent region can be made bulky, and the feel when the central absorbent portion is pressed against the excretory portion of the body can be made softer.
[0029]
In the present invention described above, menstrual blood is unlikely to diffuse on the surface, and is particularly effective in a local-contact type sanitary napkin. In other words, in recent years, sanitary napkins of the type in which the central part is raised and adhered to the local part of the woman are increasing, but even if the surface is brought into close contact with the vaginal opening to absorb menstrual blood, menstrual blood spreads on the surface. In some cases, the part of the wearer's body other than the vaginal opening becomes dirty with menstrual blood, which may cause discomfort or trouble to wipe out menstrual blood. In the present invention, since the diffusion of the liquid on the napkin surface and the layer near the surface is very small, the area other than the local part of the wearer is less contaminated with menses. Therefore, it is excellent as a sanitary napkin of the local contact type with the center raised.
[0030]
In other words, menstrual blood can be penetrated and absorbed without diffusing from the vaginal opening. Very little to give. Furthermore, when changing the napkin, the wearer can be concerned that menstrual blood will not stain the body or that menstrual blood will leak out of the napkin because the diffusion of menstrual blood seen on the surface is small. Less.
[0031]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 is a perspective view showing a sanitary napkin 1 as a first embodiment of an absorbent article according to the present invention with the surface side, which is the skin contact surface side, facing upward, FIG. 2 is a plan view thereof, and FIG. FIG. 4A is a cross-sectional view of a cross section of the sanitary napkin 1 shown in FIG. 1 taken along a horizontal center line Ox-Ox viewed from the direction of arrows II-II. FIG. FIG. 4B is an enlarged sectional view showing a part of FIG. 4A further enlarged, FIG. 5 is a sectional view showing a deformed state when worn, and FIG. 6 is a liquid permeation hole formed in a topsheet. FIG. 3 is an enlarged plan view showing an example of FIG.
[0032]
The plane shape of the sanitary napkin 1 shown in FIG. 1 is vertically long, the right side edge 1a and the left side edge 1b extending in the vertical direction are linear, and the front edge 1c and the rear edge 1d are both arc-shaped. As shown in FIG. 2, the sanitary napkin 1 has a symmetrical shape via a vertical center line Oy-Oy bisected in the horizontal direction, and also has a lateral center line Ox-Ox bisected in the vertical direction. The front half and the rear half are symmetrical.
[0033]
As shown in the cross-sectional view of FIG. 3, the sanitary napkin 1 has a liquid-impermeable back sheet 2 from below, an absorbent layer including a lower absorbent body 3 and an upper absorbent body 4, a liquid guide layer 5, and It has a structure in which a liquid-permeable top sheet 6 is laminated.
[0034]
This sanitary napkin 1 has a crimping portion 9 surrounding a region of a predetermined area. As shown in FIG. 2, this crimping portion 9 has a constant width dimension Wa and extends continuously in a belt shape. This crimping portion 9 extends right and left crimping portions 9a and 9b extending in the vertical direction at a position left and right from the vertical centerline Oy-Oy by a predetermined distance, and a predetermined distance before and after the horizontal centerline Ox-Ox. It has a front crimping portion 9c and a rear crimping portion 9d formed in the horizontal position in the horizontal position. The right crimping portion 9a and the left crimping portion 9b and the front crimping portion 9c and the rear crimping portion 9d are continuous with each other, and the right crimping portion 9a and the left crimping portion 9b have a convex shape toward the longitudinal center line Oy-Oy. The front crimp portion 9c and the rear crimp portion 9d have a curved shape that is convex in a direction away from the lateral center line Ox-Ox.
[0035]
In this embodiment, the crimping portion 9 has a symmetrical shape with respect to the vertical center line Oy-Oy, and has a symmetrical shape with respect to the front and rear direction with respect to the horizontal center line Ox-Ox.
[0036]
As shown in FIG. 2, the lower absorber 3 is separated from the right and left edge portions 3 a and 3 b of a curved shape whose convex side is directed to the vertical center line Oy-Oy, and the horizontal center line Ox-Ox. It has a wide area having a curved front edge 3c and a rear edge 3d whose convex side is directed in the direction. The upper absorber 4 has a curved shape in the same direction as the right edge 3a and the left edge 3b, and a curve in the same direction as the front edge 3c and the rear edge 3d. It has a front edge portion 4c and a rear edge portion 4d which are shapes, and the shape is substantially similar to the planar shape of the crimping portion 9.
[0037]
The upper absorber 4 has an area larger than the area surrounded by the contour 9B of the outer periphery of the crimping portion 9 and has a smaller area than the lower absorber 3. In this embodiment, the contour shape of the lower absorber 3 and the contour shape of the upper absorber 4 are bilaterally symmetrical via the vertical center line Oy-Oy, and via the horizontal center line Ox-Ox. It has a symmetrical shape back and forth.
[0038]
In the crimping section 9, the lower absorbent body 3, the upper absorbent body 4, and the topsheet 6 are pressed in a concave shape in the entire range of the right crimping section 9a, the left crimping section 9b, the front crimping section 9c, and the rear crimping section 9d. And are joined together at that point.
[0039]
As shown in FIG. 3, the liquid guide layer 5 has a structure in which chemical fibers are bonded to each other to form a three-dimensionally extending skeleton, such as an air-through nonwoven fabric, as described later. It is formed of a low-density nonwoven fabric having a large gap, and this nonwoven fabric is formed by folding two or more sheets. In this embodiment, the nonwoven fabric is folded at two broken lines to form a three-ply structure.
[0040]
The liquid guide layer 5 folded in three layers by a nonwoven fabric has a rectangular planar shape, a width dimension between the side edges 5a and 5b extending in the vertical direction is W1, and a front edge 5c extending in the horizontal direction. The length dimension between the edge and the trailing edge 5d is indicated by L1. As shown in FIG. 2, the area of the liquid guide layer 5 is sufficiently smaller than the area surrounded by the contour 9A inside the crimping portion 9, and the side edge 5a, the side edge 5b, and the front edge are formed. Neither 5c nor the trailing edge 5d is separated inward from the crimping portion 9 and does not hang on the crimping portion 9.
[0041]
In the sanitary napkin 1, a region surrounded by a contour line 9A inside the crimping portion 9 is a central absorption region 11. In the central absorbent region 11, the lower absorbent body 3 and the upper absorbent body 4 are superimposed on the back sheet 2, and the liquid guide layer 5 having a size not to be applied to the crimping portion 9 is superimposed. The structure is covered with the sheet 6.
[0042]
As shown in FIGS. 1 and 4A, in the central absorption region 11, a large number of liquid permeable holes 15 are formed in the top sheet 6 in a regular array. As shown in FIG. 4A, the liquid permeation hole 15 is formed so as to penetrate from the top sheet 6 to the liquid guide layer 5. The topsheet 6 and the liquid guide layer 5 contain thermoplastic fibers, and the liquid permeable holes 15 are formed by piercing a heated pin. At this time, the thermoplastic fibers are fused and the liquid permeable holes 15 are formed. The surface sheet 6 and the liquid guide layer 5 are bonded to each other at the portion of the hole 15. Therefore, it is not necessary to apply an adhesive to the boundary surface between the top sheet 6 and the liquid guide layer 5, and when the liquid permeates from the top sheet 6 to the liquid guide layer 5, a decrease in the permeation area due to the adhesive is reduced. Will not occur.
[0043]
At the interface between the upper absorber 4 and the liquid guide layer 5, the upper absorber 4 and the liquid guide layer 5 are bonded by a hot-melt adhesive applied in a net, comb or spiral shape. I have. In addition, the upper and lower surfaces of the upper absorbent body 4 and the lower absorbent body 3 are covered with a hydrophilic tissue, so that an adhesive is interposed at the interface between the upper absorbent body 4 and the lower absorbent layer. Absent. Further, the boundary surface between the lower absorbent body 3 and the back sheet 2 is also bonded with a hot melt adhesive.
[0044]
The area where the lower absorber 3 and the upper absorber 4 are present on the outer peripheral side of the outer contour line 9B of the crimping portion 9 is the auxiliary absorption area 12. In the auxiliary absorption region 12, a bulky portion 12a in which the lower absorber 3, the upper absorber 4, and the topsheet 6 are superimposed is formed immediately on the outer peripheral side of the contour line 9B. , A thin region 12b in which the lower absorbent body 3 is covered with the topsheet 6 is provided. Then, on the outer peripheral side beyond the auxiliary absorption region 12, the back sheet 2 and the top sheet 6 are bonded by a hot melt adhesive without interposing the lower absorber 3 and the upper absorber 4. .
[0045]
As shown in FIGS. 1 and 2, the bulky portion 12a of the auxiliary absorption region 12 is formed so as to surround the entire outer periphery of the crimping portion 9, and the thin region 12b is formed of the bulky portion 12a. It is formed so as to surround the entire outer periphery.
[0046]
Next, a preferred example of each constituent material will be described.
As the topsheet 6, an air-through nonwoven fabric formed of chemical fibers is preferably used. As the chemical fiber, a core-in-sheath type composite synthetic fiber having a core portion of polyethylene terephthalate (PET) containing titanium oxide of about 1.1% by mass and a sheath portion of polyethylene (PE) is used. Synthetic fibers are bonded together by heat fusion. The core-sheath type composite synthetic fiber in which titanium oxide is added to the core has a good surface slipperiness and a good feel of the topsheet 6. If an air-through nonwoven fabric is used as the topsheet 6, the bulkiness is high and voids are formed between the fibers, so that the liquid permeability is good.
[0047]
The core-sheath type composite synthetic fiber forming the topsheet 6 has a hydrophilic oil agent such as a surfactant kneaded into the inside thereof, or the surface thereof is coated with the hydrophilic oil agent to be subjected to a hydrophilic treatment. It is preferably formed by mixing fibers with water-repellent fibers having a surface coated with a water-repellent oil agent. Mixing the water-repellent fibers has the effect of preventing liquid diffusion on the topsheet 6. In the case where water-repellent fibers are mixed, a structure is adopted in which a large number of liquid permeable holes 15 are formed in the top sheet 6 as shown in FIG. Is preferred. The water-repellent fibers are preferably contained in a mass ratio of 5 to 30% with respect to the mass of the topsheet 6. If it exceeds 30%, the liquid is easily repelled on the surface of the topsheet 6 and the liquid permeation ability of the topsheet 6 is reduced. Further, when it is less than 5%, the effect of preventing liquid diffusion is reduced.
[0048]
Further, the topsheet 6 may be a point-bonded nonwoven fabric or spunbonded nonwoven fabric formed of chemical fibers, or a spunlace nonwoven fabric containing hydrophilic fibers such as rayon and the water-repellent fibers. Alternatively, a resin film having a large number of liquid permeable holes or a laminate of a resin film and a nonwoven fabric having a large number of liquid permeable holes may be formed.
[0049]
In any case, the basis weight of the top sheet 6 is 15 to 60 g / m. ² Is preferable. If it is less than the above, sufficient surface strength cannot be obtained, and tearing may occur in a wet state. If the thickness exceeds the above range, the topsheet 6 becomes stiff and may cause discomfort during wearing. The density of the topsheet 6 is 0.12 g / cm. ³ The following is preferred. Since menstrual blood at the time of menstruation of a woman has a relatively high viscosity, it is preferable that the density be equal to or less than the above value in order to transmit the menstrual blood.
[0050]
As shown in FIGS. 4A and 6, the liquid permeation hole 15 has an opening dimension Hd on its surface of 0.5 to 2.0 mm, a vertical arrangement pitch Hy of 2 to 5 mm, The arrangement pitch Hx in the horizontal direction is 1 to 4 mm, Hy is longer than Hx, and the arrangement of the liquid permeable holes 15 is such that the liquid permeable holes 15 are alternately located in the X direction and the Y direction as shown in FIG. Relationship.
[0051]
The liquid guide layer 5 has a structure in which hydrophilic chemical fibers, for example, surfactants are kneaded or chemical fibers coated on the surface are joined together to form a three-dimensional skeleton and have voids. Things. By using the liquid guide layer 5 having such a gap, the liquid easily penetrates through the topsheet 6 and enters the gap by its own weight, and the liquid is absorbed by the absorbing layer located thereunder. Thus, the liquid can be held in the gap.
[0052]
Examples of the above-mentioned structure include an air-through nonwoven fabric formed of hydrophilic chemical fibers and having a liquid permeation function, and an air-laid nonwoven fabric having a liquid permeation function and a liquid holding function.
[0053]
The air-through nonwoven fabric uses a fiber layer of an eccentric core-in-sheath type composite synthetic fiber having a core of polypropylene (PP) and a sheath of polyethylene (PE) (for example, having a fineness of 4.4 dtex and a fiber length of 50 mm). In this case, the sheath portions of the core-sheath type composite synthetic fibers are bonded together by hot fusion with hot air.
[0054]
Alternatively, the air-through non-woven fabric has a core portion made of polyethylene terephthalate (PET) containing titanium oxide at about 1.1% by mass and a sheath portion made of polyethylene (PE), and has a core-sheath composite synthetic fiber (for example, having a fineness of 2.2 dtex). And a fiber length of 44 mm), and the sheath portions of the core-in-sheath type composite synthetic fibers were bonded together by hot fusion using hot air.
[0055]
The density of the air-through nonwoven fabric that can be used as the liquid guide layer 5 is 0.005 g / cm. ³ 0.1g / cm ³ However, it is preferable to use the air-through nonwoven fabric fed from the raw material as the liquid guide layer 5 after heat-treating to recover the bulk.
[0056]
For example, the thickness of the air-through nonwoven fabric is set to 1.2 by subjecting the above-mentioned air nonwoven fabric to a heat treatment at 115 ° C to 300 ° C, preferably at 130 ° C to 200 ° C (for example, for 1 minute with 135 ° C hot air). It can be recovered in a range of up to 4 times.
[0057]
Preferably, the air-through nonwoven fabric is cooled after the bulk is recovered by heat-treating the air-through nonwoven fabric. As a result, the bulk recovered by the heat treatment can be maintained as it is by rapid cooling, and an air-through nonwoven fabric having low density and cushioning properties can be obtained.
[0058]
The density of the air-through nonwoven fabric after the bulk recovery is lower than that of the upper absorber 4 and the surface sheet 6, and is 0.005 g / cm in a dry state. ³ 0.02 g / cm ³ Those in the range are preferably used. When the density is less than the above range, the space between the fibers becomes too small, and the liquid permeates through the topsheet 6 and becomes difficult to enter into the gap by its own weight, and menstrual blood from the topsheet 6 to the upper absorbent body 4A is reduced. Guidance function deteriorates. On the other hand, if it exceeds the above range, the voids become too large, the strength of the skeleton extending in the three-dimensional direction of the fiber decreases, and the bulk tends to be collapsed by pressure with the body.
[0059]
The air-through nonwoven fabric after bulk recovery is 980 Pa (10 g / cm) in a wet state. ² ) Is 0.005 g / cm. ³ ~ 0.04g / cm ³ Is preferably within the range.
[0060]
The thickness of the air-through nonwoven fabric after the bulk is recovered is 1.5 mm to 3 mm, preferably 2 mm to 3 mm in a dry state and a wet state. 980 Pa (10 g / cm ² The thickness when the pressure is applied is 0.5 mm to 2 mm, and preferably 0.5 mm to 1.5 mm. The thickness recovery ratio after the pressure is removed is preferably 1.5 times or more, and more preferably 1.8 times or more when the pressure is set to 1. It is preferable that the liquid guide layer 5 is formed by stacking a plurality of the air-through nonwoven fabrics.
[0061]
The measurement of the thickness and density in the dry state and the wet state, and the thickness and density in the wet state and when the pressure was applied were measured by the following method (Example B) (11). Based.
[0062]
When the liquid guide layer 5 is used, a gap can be maintained in the liquid guide layer 5 even when menstrual blood is repeatedly given and when body pressure is applied, and the liquid is supplied in the liquid guide layer 5. The liquid can be guided and held, and the liquid can be prevented from returning to the topsheet 6. Further, when the body pressure is reduced, the bulk can be immediately recovered, and the function of permeating the liquid given repeatedly can be maintained for a long time.
[0063]
The basis weight of the entire liquid guide layer 5 is 15 to 300 g / m. ² And more preferably 20 to 100 g / m ² It is. Within the above range, the liquid can be transferred to the absorbing layer in the liquid guiding layer 5, and the liquid can be held in the voids in the liquid guiding layer 5 while the liquid is absorbed by the absorbing layer. .
[0064]
The air-laid nonwoven fabric used as the liquid guide layer 5 is obtained by floating a mixture of the hydrophilic natural fiber or regenerated cellulose fiber and a thermoplastic resin fiber as a chemical fiber in the air, and collecting the fiber on a screen. After laminating and laminating, a heat treatment is performed to melt the surface of the thermoplastic resin fiber and heat-weld the thermoplastic resin fiber and the hydrophilic fiber. For example, as the hydrophilic fiber, wood pulp, rayon, acetate rayon, natural cellulose fiber other than pulp, mercerized pulp, cross-link pulp, and the like are used. Core-sheath fibers of (PE) (for example, a fineness of 1.7 dtex and a fiber length of 13 mm) are used.
[0065]
Further, the fibers may be bonded with an emulsion type resin binder.
[0066]
This air-laid nonwoven fabric also has a three-dimensional skeleton structure in which chemical fibers are bonded to each other or the hydrophilic fibers and the chemical fibers are bonded to form voids. When this air-laid nonwoven fabric is used as the liquid guide layer 5, the air-laid nonwoven fabric has a liquid permeation function by allowing the liquid to enter into the voids by its own weight, like the air-through nonwoven fabric, and contains hydrophilic fibers such as natural fibers and regenerated cellulose fibers. Therefore, the liquid that is to stay on the topsheet 6 can be drawn into the liquid guide layer 5 by the hydrophilic action.
[0067]
It is also preferable that the air-laid nonwoven fabric is heat-treated at a temperature of 100 to 300 ° C., preferably 130 to 200 ° C. for about 1 minute after being pulled out of the raw fabric to recover the bulk. When using an air-laid nonwoven fabric, the density when dry, the density when wet and pressurized, the thickness of one nonwoven fabric, the thickness when wet and pressurized, the recovery rate of the thickness when removed under pressure, A preferred range such as a basis weight is the same as that of the air-through nonwoven fabric.
[0068]
For the liquid guide layer 5, a non-woven fabric obtained by treating a web by a manufacturing method such as a needle punching method or a high loft method is used, and the heat-treated non-woven fabric is used. It is also possible to use a material that has a typical skeleton and recovers its bulk by applying heat, such as urethane.
[0069]
In addition, the liquid guide layer 5 may be formed of the air-through nonwoven fabric or the air-laid nonwoven fabric in which the whole is heat-treated to recover the bulk, but the liquid guide layer 5 is partially heat-treated to recover the bulk. There may be a portion that has been made to remain and a portion that does not recover its bulk. For example, when the liquid guide layer 5 having a long longitudinal dimension is used, only the front portion facing the vaginal opening is heat-treated to have a low density, and the portion facing the posterior anus or the buttocks groove restores bulk. Alternatively, the state may be higher than the front part. Thereby, menstrual blood given in a short time can be quickly transferred to the absorbent layer in a portion facing the vaginal opening, and a relatively small amount given to the topsheet can be provided in the rear portion by maintaining high density. Can be quickly drawn in. Alternatively, conversely, only the rear portion may be heat-treated without heat treatment of the front portion, and only the rear portion may have low density.
[0070]
The fineness of the fibers constituting the liquid guide layer 5 may be 1.8 to 33 dtex, but the bulk recovery when the pressing force from the body is released is good, and the liquid return phenomenon (wet back phenomenon) The fineness is preferably in the range of 2.4 to 11 dtex in order to reduce the occurrence of the fineness.
[0071]
The liquid guide layer 5 is formed by folding the nonwoven fabric into three layers. Here, if it is attempted to manufacture a single nonwoven fabric having the same basis weight as a three-ply folded nonwoven fabric, the fiber density increases, the thickness also decreases, and the internal voids decrease. Accordingly, the function of guiding the liquid into the void by its own weight is reduced. Further, as shown in FIG. 3, the two fold lines of the three-layer nonwoven fabric are oriented in the vertical direction, and both fold lines are located at the side edge 5a and the side edge 5b of the liquid guide layer 5, respectively. Each layer in the stack becomes easy to move in the horizontal direction in FIG. 3 at the interface between the layers. That is, the liquid guide layer 5 has a degree of freedom in the left-right direction, and the liquid guide layer 5 can relatively freely move according to the movement of the body in a state where the central absorption region 11 is in close contact with the vaginal opening. Therefore, the adhesion between the region where the liquid guide layer 5 is provided and the vaginal opening can be always maintained, and the feeling of discomfort given to the vaginal opening can be reduced.
[0072]
The number of layers obtained by folding the nonwoven fabric in the liquid guide layer 5 is not necessarily limited to three layers, but may be two layers, four layers or more. When the number of stacked sheets is increased, the liquid can enter the voids between the layers of the nonwoven fabric, and the liquid supplied to the topsheet 6 can be guided to the liquid guide layer 5 in a large amount. However, if the number of times of folding is too large, the number of steps for forming the liquid guide layer 5 increases, and the productivity decreases. Also, when the number of layers increases, the gap between the layers becomes too large, and there is a possibility that the liquid may stay in that portion.
[0073]
Therefore, the number of times of folding the nonwoven fabric is preferably about two to five sheets in view of the liquid guiding function and production efficiency. However, as described above, in order to allow each layer of the nonwoven fabric to have a degree of freedom in the left-right direction and to make the number of interfaces between the layers appropriate, it is a preferable embodiment to stack three layers.
[0074]
Further, as the liquid guide layer 5, for example, three nonwoven fabrics cut into a size of W1 × L1 can be stacked. Such a stack can function similarly to the folded one in terms of density and freedom of each layer. However, in order to prevent the liquid guide layer 5 from being caught in the crimping portion 9, it is necessary to cut the nonwoven fabric so that the width dimension W1 is very small. It is difficult to cut to such a small size, and it is therefore desirable to fold the nonwoven fabric to form the liquid guide layer 5 having a size of W1 × L1.
[0075]
The upper absorber 4 is a laminate of pulp such as pulverized pulp, mercerized pulp, and cross-linked pulp, and has a basis weight of, for example, 230 g / m2. ² Formed of The lower absorbent core 3 contains 1.5 to 2.0% by mass of the superabsorbent polymer with respect to the pulp, and has a basis weight and a thickness of 80% or less of the upper absorbent body 4, for example, a basis weight. Is 160 g / m ² Is used. Further, the upper absorber 4 and the lower absorber 3 are used in a state where they are stacked, and the upper and lower surfaces thereof are sanded with a tissue. The lower absorber 3 has an embossed lattice pattern 15 as shown in FIG.
[0076]
The density of the upper absorber 4 and the lower absorber 3 is 0.1 to 0.6 g / cm. ³ Is preferable. If it is less than the above range, the rigidity becomes too low to maintain the shape of the sanitary napkin 1, and wrinkles and twists may occur when worn on the body. In addition, when the ratio exceeds the above range, the body becomes rigid and easily gives a sense of discomfort to the body. However, the lower layer absorber 3 has a higher density than the upper layer absorber 4 in the above density range due to the formation of the lattice pattern embossment on the lower layer absorber 3 as described above.
[0077]
Further, in order to facilitate the liquid guided to the liquid guide layer 5 to be sucked into the upper absorber 4, the density of the upper absorber 4 is preferably at least twice the density of the liquid guide layer 5. And more preferably 5 times or more.
[0078]
The back sheet 2 is a liquid-impermeable and air-permeable sheet, such as a polyethylene (PE) film or a polypropylene (PP) film in which fine air holes are formed. For example, CaCo is added to the plastic sheet. ₃ , BaSo ₄ By mixing and stretching inorganic fillers and the like, fine ventilation holes are appropriately dispersed and formed in the film, the air permeability is improved, and the thickness is about 15 to 50 μm. . Alternatively, a material obtained by laminating a thermoplastic resin on a nonwoven fabric may be used.
[0079]
As shown in FIG. 3, a pressure-sensitive adhesive layer 7 is applied to the outer surface of the back sheet 2 in a strip shape so as to extend continuously in a vertical direction with a predetermined width. Before use, the pressure-sensitive adhesive layer 7 is covered and protected by a release sheet (not shown).
[0080]
The pressure-bonding portion 9 is formed by embossing using a heating roller, and the lower absorber 3, the upper absorber 4, and the topsheet 6 are superposed on the outer surface of the lower absorber 3, A flat roll is applied, and a heating roll having an embossed pattern convex portion is applied to the surface side of the top sheet 6, and the lower absorbent member 3, the upper absorbent member 4, and the top sheet 6 are pressed against the convex portion. And it is heated. As a result, in the crimping portion 9, as shown in FIG. 2, the thermoplastic fibers contained in each layer and the sheet are melted at a portion having a width dimension of δ to form a film-like melting portion 9 </ b> D. Although not in the form of a film, a high-density portion 9E in which the absorption layer has a higher density than the region other than the crimping portion 9 is formed between the fusion portions 9D.
[0081]
Then, after the crimping portion 9 is formed on the three layers, the back sheet 2 is attached to the lower side of the lower absorber 3.
[0082]
In this embodiment, the fusion portion 9D is formed in an inclined line shape with respect to the direction in which the crimping portion 9 extends. The width dimension δ of the fusion zone 9D is, for example, 0.2 to 1.5 mm, and the pitch P of the fusion zone 9D is, for example, 1 to 5 mm. The width Wa of the crimping portion 9 is about 2 to 4 mm.
[0083]
As described above, in order to properly form the fusion zone 9D and the high-density zone 9E, the temperature of the heating roll is set to 120 ° C. or more, and the pressure between the rolls is selected in the range of 980 to 2450 Pa. preferable. When the crimping portion is formed at the above-described temperature and pressure, the crimping portion 9 is adhered to the underwear and attached to the body, and receives pressure from the thighs from both sides, as shown in FIG. The sanitary napkin 1 is easily bent at the portion of the left crimping portion 9b. Further, the problem that the pressure for forming the emboss becomes too high and the melted portion 9D is broken does not occur.
[0084]
Further, as described above, in the central absorption region 11, each edge of the liquid guide layer 5 is located inside the press-fit portion 9 so that the liquid guide layer 5 does not hang on the press-fit portion 9. If the liquid guide layer 5 hangs on the crimping portion 9, the nonwoven fabric forming the liquid guide layer 5 is bulky and has a three-dimensional skeleton formed by fibers. The strength will be reduced. In this case, the topsheet 6 and the upper absorbent body 4 are not fixed or weakly fixed in the crimping portion 9, and menstrual blood given to the central absorption region 11 spreads along the topsheet 6 or the upper absorbent body 4 When the inside is diffused, it becomes impossible to prevent the liquid from diffusing at the press-bonding portion 9.
[0085]
Also, if the pressure-bonding strength at the pressure-bonding portion 9 is weak, it is difficult to deform the central absorbent region 11 into a convex shape toward the body, and the respective sheets are displaced in the central absorbent region 11 and the periphery thereof, so that the topsheet 6 or the liquid The guide layer 5 is easily twisted. As a result, it is difficult to bring the central absorption region 11 into close contact with the vaginal opening, and the initial objective of absorbing the liquid spotwise in the central absorption region 11 cannot be achieved.
[0086]
As described above, by configuring the liquid guide layer 5 so as not to hang on the crimping portion 9, the central absorption region 11 can be deformed in a protruding manner toward the body, and the central absorption region 11 can be softly placed on the vaginal opening. It becomes possible to make them adhere. In addition, the function of preventing the diffusion of the liquid can be exerted by the crimping portion 9.
[0087]
Hereinafter, preferred dimensions of each part will be described. The sanitary napkin 1 of the first embodiment has a normal size used in the daytime or the like, and has a width of 80 mm at the horizontal center line Ox-Ox and a length at the vertical center line Oy-Oy. It is about 210 mm.
[0088]
In addition, the central absorbent region 11 surrounded by the crimping portion 9 needs to have an area capable of closely adhering to the female vaginal opening, the width dimension W2 is in the range of 25 mm to 50 mm, and the vertical dimension L1 is It is in the range of 50 to 110 mm. In the long type suitable for wearing at night shown in FIG. 8, it is preferable that the central absorption region 11 extends to a region behind the anus. In this case, the central absorption region 11 has a vertical dimension. The upper limit is about 280 mm.
[0089]
The width dimension W1 and the vertical dimension L1 of the liquid guide layer 5 are set according to the area of the central absorption region 11, and the edge 9 of the liquid guide layer 5 and the inner contour line 9A of the crimping portion 9 are formed. It is necessary to keep a certain distance between them. For example, the distance between the edge of the liquid guide layer 5 and the contour 9A, that is, (W2-W1) / 2 and (L2-L1) / 2 is preferably in the range of 1 to 10 mm, and more preferably. 2 to 6 mm. When the thickness is within the above range, there is no possibility that the edge of the liquid guide layer 5 is caught on the crimping portion 9 when the crimping portion 9 is formed.
[0090]
In the above embodiment, the width of the upper absorber 4 at the horizontal center line Ox-Ox is about 55 mm, and the length at the vertical center line Oy-Oy is about 120 mm. The lower absorber 3 has a width of about 75 mm and a length of about 180 mm. The width Wb of the bulky portion 12a in the auxiliary absorption region shown in FIG. 3 is preferably about 3 to 10 mm.
[0091]
When this sanitary napkin 1 is used, first, the release sheet protecting the pressure-sensitive adhesive layer 7 is peeled off, and is adhered to the inside of the crotch portion 20 of the underwear via the pressure-sensitive adhesive layer 7. use.
[0092]
While the underwear and the sanitary napkin 1 are worn on the body, the crotch portion 20 and the sanitary napkin 1 receive the tightening force of the thigh from both sides. In the sanitary napkin 1, the right crimping portion 9a and the left crimping portion 9b extending in the vertical direction at equal distances in the horizontal direction from the vertical center line Oy-Oy are formed. In the napkin 1, the right crimp portion 9a and the left crimp portion 9b function as hinges, and the sanitary napkin 1 is bent with the hinge portions as folding lines as shown in FIG.
[0093]
In particular, the liquid guide layer 5 provided in the central absorption region 11 does not hang on the crimping portion 9, and the crimping portion 9 only has the lower absorber 3 and the upper absorber 4. Therefore, the rigidity difference and the thickness difference between the crimping portion 9 and the region other than the crimping portion 9 can be increased, and the sanitary napkin 1 can be easily bent at the positions of the right crimping portion 9a and the left crimping portion 9b.
[0094]
At this time, the tightening force from the thigh acts on the central absorbent region 11 from the right side crimping portion 9a and the left side crimping portion 9b, and the surface of the central absorbing region 11 projects toward the body due to the tightening force. And the surface of the topsheet 6 located in the central absorption region 11 is likely to adhere to the female vaginal opening. At this time, the central absorbent region 11 is bulky with the lower absorbent body 3, the upper absorbent body 4, and the liquid guide layer 5, and the liquid guide layer 5 is made of a material having a low density. The contact feeling is soft.
[0095]
Relatively high-viscosity liquid such as menstrual blood excreted from the vaginal opening is mainly given to the top sheet 6 in the central absorption region 11, and this liquid passes through the top sheet 6 and is given to the liquid guide layer 5. . That is, since the liquid guide layer 5 has a structure in which chemical fibers are bonded and has a skeleton extending in the three-dimensional direction to form voids, the liquid permeates the topsheet 6 by its own weight, The liquid is guided into the space of the liquid guide layer 5. Further, the liquid absorbed in the liquid guide layer 5 is sucked by the hydrophilic action and the capillary action of the high-density upper absorbent body 4 located thereunder, and is absorbed and held by the upper absorbent body 4. Further, the liquid absorbed by the upper absorber 4 is absorbed and held by the lower absorber 3 thereunder.
[0096]
The liquid guide layer 5 has a high ability to transfer the liquid downward, and the liquid is held in the liquid guide layer 5 until the liquid is sucked by the upper absorbent body 4. Difficult to saturate. Therefore, the topsheet 6 is unlikely to give a moist feeling to the skin of the body.
[0097]
When a pressing force due to the weight of the body acts in a sitting posture or the like, the pressing force is received by the top sheet 6 and the liquid guide layer 5. Since the liquid guide layer 5 is a low-density layer whose bulk has been recovered by heat treatment, it can function as a cushion layer. Further, since the porosity can be maintained high even when the liquid guide layer 5 is compressed by the pressing force applied from the body, the liquid given from the topsheet 6 is temporarily held and applied to the upper absorbent body 4. You can keep the function of sucking in for a long time. Further, when the pressing force from the body is released, the liquid guiding layer 5 has a high function of restoring the bulk, so that the liquid guiding layer 5 is always formed with a void.
[0098]
The topsheet 6 contains water-repellent fibers, which can prevent the liquid from diffusing. However, as described above, the topsheet 6 can maintain its bulk and easily maintain a state in which voids are formed inside. Therefore, even if the water-repellent fibers are included, the liquid permeation function of the topsheet 6 can be sufficiently exhibited.
[0099]
In this embodiment, as shown in FIG. 4A, since a large number of liquid permeable holes 15 are formed from the top sheet 6 to the liquid guide layer 5, the liquid given to the surface of the top sheet 6 The liquid is transmitted to the liquid guide layer 5 through the liquid permeation hole 15. Therefore, the liquid applied to the top sheet 6 is likely to fall to the liquid guide layer 5 by its own weight, which makes it easier to further prevent the remaining liquid and the diffusion of the liquid on the top sheet 6.
[0100]
As described above, in the sanitary napkin 1, the liquid repeatedly and intensively applied to the central portion of the central absorption region 11 is transmitted to the liquid guide layer 5 through the topsheet 6, and the liquid is applied to the topsheet 6 by the liquid. It is difficult to spread. In addition, since the liquid guide layer 5 has a low density, the diffusion of the liquid in the liquid guide layer 5 to the surroundings is suppressed, whereby the diffusion of the liquid in the topsheet 6 can be suppressed.
[0101]
The liquid that has passed through the topsheet 6 and the liquid guide layer 5 is absorbed and diffused by the upper absorber 4 and further absorbed and diffused by the lower absorber 3. However, in the central absorption region 11, since the distance between the upper absorber 4 and the topsheet 6 is large, the color of menstrual blood diffused in the upper absorber 4 is difficult to visually confirm from the front side. Become. As described above, the diffusion region of the liquid in the topsheet 6 is limited, and the diffusion of the liquid in the upper absorbent body 4 is not visible from the front side, so that the wearer visually observes the surface of the sanitary napkin 1 in use. Sometimes it is easy to prevent feeling psychogenic anxiety.
[0102]
Further, when the liquid diffuses to the surroundings in the upper absorbent body 4 and the lower absorbent body 3 located in the central absorbent region 11, the pressure-bonding portion 9 functions to prevent the diffusion of the liquid. That is, the liquid that has spread through the upper absorber 4 and the lower absorber 3 and spreads laterally to reach the right compression part 9a and the left compression part 9b concentrates in the high-density part 9E, and further flows between the high-density parts 9E. Then, it propagates in the vertical direction along the right crimping portion 9a and the left crimping portion 9b. Therefore, the liquid supplied to the central absorption region 11 becomes difficult to be transmitted to the auxiliary absorption region 12 around the pressure bonding portion 9.
[0103]
An auxiliary absorption region 12 is provided on the outer periphery of the central absorption region 11, but as shown in FIG. 4B, a bulky portion 12a having a large thickness exists immediately outside the crimping portion 9. In the deformed state as shown in FIG. 5, the bulky portion 12a is easily fitted to the crotch portion outside the labia majora. Also, as shown in FIG. 5, the crimping portions 9 are both buried between the bulky central absorption region 11 and the bulky portion 12a, so that the crimping portions 9 having high density and high rigidity do not directly touch the body. The crimping portion 9 does not give a rigid feeling to the body.
[0104]
When menstrual blood transmitted through the crotch adheres to the auxiliary absorption region 12, or when menstrual blood transmitted along the surface of the central absorption region 11 adheres to the surface of the auxiliary absorption region 12 beyond the crimping portion 9, The liquid quickly penetrates through the topsheet 6 and is absorbed by the top absorber 4 due to the liquid's absorbing power due to the capillary action of the top absorber 4 located directly below the topsheet 6. As described above, the liquid absorbed by the upper absorbent body 4 and the lower absorbent body 3 in the central absorbent area 11 is hardly transmitted to the outside beyond the pressure-bonding portion 9. 4 and the lower absorber 3 are unlikely to be saturated with a large amount of liquid. In addition, the lower absorber 3 and the upper absorber 4 are located in the auxiliary absorption region 12, so that the volume of the material of the absorption layer is increased. For this reason, the liquid adhering to the surface of the top sheet 6 in the auxiliary absorption region 12 is immediately absorbed by the absorption layer therebelow, and the lateral leakage of the liquid is easily prevented.
[0105]
In addition, in the auxiliary absorption area 12, the upper absorbent body 4 having a high density is located directly below the topsheet 6, and the liquid attached to the surface of the topsheet 6 is quickly sucked by its hydrophilicity and capillary action. In the auxiliary absorption region 12, it is not necessary to provide a liquid permeable hole in the topsheet. However, a liquid permeable hole may be formed in the top sheet 6 in the auxiliary absorption region 12.
[0106]
In addition, the lower absorbent body 3 is provided in a wide range between the central absorbent area 11 and the auxiliary absorbent area 12, and although the lower absorbent body 3 has a small basis weight and a small thickness, it has a high absorbent polymer inside, The lower absorbent body 3 has a large liquid holding capacity. Therefore, in the central absorption area 11 and the auxiliary absorption area 12, a large amount of liquid can be held in the lower absorbent body 3, and the sanitary napkin 1 as a whole has a large liquid absorption capacity.
[0107]
As described above, in the sanitary napkin 1, the central absorption region 11 is defined by the crimping portion 9, and the central absorption region 11 is easily brought into close contact with the vaginal opening, and mainly receives the liquid in the central absorption region 11. Like that. In the central absorption region 11, the topsheet 6 is unlikely to be saturated when liquid is repeatedly supplied, and the liquid in the topsheet 6 is not easily diffused. When the liquid adheres to the auxiliary absorption region 12 beyond the central absorption region 11, the auxiliary absorption region 12 functions to immediately capture the liquid.
[0108]
7 to 11 show another embodiment of the present invention. In these embodiments, the same components as those in the first embodiment are denoted by the same reference numerals as those in the first embodiment, and detailed descriptions thereof will be omitted.
[0109]
FIG. 7 is a plan view showing a sanitary napkin 1A as an absorbent article according to the second embodiment of the present invention.
[0110]
This sanitary napkin 1A differs from the sanitary napkin 1 shown in FIGS. 1 to 5 only in the pattern shape of the crimping portion 9, and in all other configurations and dimensions.
[0111]
In the sanitary napkin 1A shown in FIG. 7, only the right crimp portion 9a and the left crimp portion 9b are formed as crimp portions, and the front crimp portion 9c and the rear crimp portion 9d of the sanitary napkin 1 shown in FIG. 1 are formed. Not. The structure of the right crimping portion 9a and the left crimping portion 9b is the same as that of the sanitary napkin 1 shown in FIGS.
[0112]
In this sanitary napkin 1A, the right crimping portion 9a and the left crimping portion 9b extending in the vertical direction are provided on both left and right sides, so that the deformed state when worn on the crotch portion is the same as in FIG. In the sanitary napkin 1A, a region sandwiched between the right-side crimping portion 9a and the left-side crimping portion 9b is the central absorption region 11A, which is located to the right outside of the right-side crimping portion 9a and to the left of the left-side crimping portion 9b. Outside, an auxiliary absorption region 12A is formed. The function of guiding and absorbing the liquid in the central absorption region 11A and the auxiliary absorption region 12A is the same as the central absorption region 11 and the auxiliary absorption region 12 of the sanitary napkin 1.
[0113]
The sanitary napkin 1A is also symmetrical with respect to the left / right direction via the vertical center line Oy-Oy, and is also symmetrical with respect to the front / rear direction via the horizontal center line Ox-Ox. The length Lb from the lateral center line Ox-Ox to the front ends of the right crimping portion 9a and the left crimping portion 9b is greater than the length La from the lateral center line to the front edge 5c of the liquid guide layer 5. Is also getting longer. The same applies to the length from the lateral center line to the rear ends of the right and left crimping portions 9a and 9b, and the length from the rear edge 5d of the liquid guide layer 5.
[0114]
And Lb-La is preferably at least 3 mm, more preferably at least 5 mm.
[0115]
With such a configuration, the menstrual blood that is supplied to the central portion of the central absorbent region 11A and absorbed by the upper absorbent member 4 and the lower absorbent member 3 from the top sheet 6 via the liquid guide layer 5 is When each of the absorbers 3 and 4 is diffused to both sides, the diffusion can be prevented by the right-side crimping portion 9a and the left-side crimping portion 9b, and each of the absorbers 3 and 4 located in the auxiliary absorption region 12A is liquid. Saturation is less likely.
[0116]
FIG. 8 is a plan view showing a sanitary napkin 1B as an absorbent article according to the third embodiment of the present invention.
[0117]
The sanitary napkin 1B has the same basic structure as the sanitary napkins 1 and 1A and 1D, but differs only in the overall size and the shape of the flat pattern of the crimping portion.
[0118]
The sanitary napkin 1B has a long dimension in the vertical direction and a wide width direction at the rear, and is a so-called hip guard portion that can be attached to the buttocks at the rear when worn on the crotch.
[0119]
In the sanitary napkin 1B, the vertical dimension of the back sheet, the lower absorbent body 3A, the upper absorbent body 4A, and the liquid guide layer 5A is long. The crimping portion 90 also has a pattern that is long in the vertical direction. The vertically long crimping section 90 has a right crimping section 90a, a left crimping section 90b, a front crimping section 90c, and a rear crimping section 90d which are continuously formed so as to surround the central absorption region 11B. Further, a pair of front extension crimp portions 90e and 90f are provided forward of the front crimp portion 90c. The front extension crimping portions 90e and 90f are inclined and extend so that the distance between them increases toward the front, and the front ends of the front extension crimping portions 90e and 90f extend from the edge of the sanitary napkin. It is far away.
[0120]
Further, a short inner crimp portion 90g is provided inside the right crimp portion 90a, and a similarly short inner crimp portion 90h is provided inside the left crimp portion 90b.
[0121]
As shown in FIG. 8, each portion of the crimping portion 90 has a predetermined width dimension. Within this width, as in the embodiment shown in FIG. The high-density portions 9E are alternately formed along the line direction of the crimping portion.
[0122]
The liquid guide layer 5A has a vertically long area in the central absorption region 11B and is provided so as not to be caught on the crimping portion 90. An auxiliary absorption region 12B is formed on the outer periphery of the crimping portion 90.
[0123]
In this sanitary napkin 1B, since the central absorption region 11B is elongated in the vertical direction, the central absorption region 11B can be fitted from the vaginal opening to the buttocks. The pattern shape of the crimping portion 90 is such that the sanitary napkin is easily bent at the portions of the front extension crimping portions 90e and 90f, so that the sanitary napkin easily fits near the muzzle in front of the vaginal opening.
[0124]
In addition, since the front region and the rear region of the central absorption region 11B can be easily bent starting from the inner crimping portions 90h and 90g, the front region of the central absorption region 11B fits into the vaginal opening, and the rear region is in the groove of the buttocks. It becomes easy to fit.
[0125]
The menstrual blood applied to the top sheet 6A can be guided to the upper absorbent body 4A and the lower absorbent body 3A thereunder by the liquid guide layer 5A located in the central absorbent area 11B. The collected menstrual blood is unlikely to diffuse along the top sheet 6 from the central absorption region 11B to the periphery beyond the crimping portion 90. Therefore, even if the length of the back portion of the sanitary napkin 1B, that is, the hip guard portion, is small or thin in the vertical and horizontal directions, it is easy to prevent menstrual blood from leaking in the buttocks direction.
[0126]
Although the liquid guide layer 5A is vertically long, the right crimp portion 90a, the left crimp portion 90b, the front crimp portion 90c and the rear crimp portion 90d, and the front extension crimp portions 90e and 90f, and more preferably the inner crimp portions 90g and 90h. It is at a position away from each of the crimping parts so as not to be caught. Therefore, each of the crimping portions can be formed in a uniform compressed state, and the entire sanitary napkin 1B is easily deformed so as to fit the body. In particular, when the liquid guide layer 5A is arranged so as not to be hung on the inner crimping portions 90g and 90h, the inner crimping portions 90g and 90h can be formed in a uniform crimping state, and the front and rear regions of the central absorption region 11B can be formed. Can be easily bent starting from the inner crimping portions 90g and 90h.
[0127]
Further, the liquid guide layer 5A may be hung on the inner crimping portions 90g and 90h. For example, when the liquid guide layer 5A has a large thickness or is formed of a material having high flexural rigidity, the liquid guide layer 5A is compressed by the inner crimping portions 90g and 90h to form the vertically long liquid guide layer 5A. The central absorbing region 11B having the inner crimping portions 90g and 90h can be easily bent as described above.
[0128]
In the embodiment of FIG. 8, the front extension crimping portions 90e and 90f and the inner crimping portions 90g and 90h may not be particularly provided.
[0129]
Each of the sanitary napkins 1, 1 A, and 1 B in each of the embodiments has a shape having no wings on both side edges. It may have a wing portion that protrudes in the direction.
[0130]
FIG. 9 shows a fourth embodiment in which the wing portion is formed based on the structure of the sanitary napkin 1 shown in FIGS. 1 and 2 as an example.
[0131]
The sanitary napkin 1C shown in FIG. 9 is provided with a pair of wing portions 21 and 21 extending from both sides of the sanitary napkin substantially at the center. In this sanitary napkin 1C, both side edges of the back sheet 2 have the same shape as the wing portions 21 and 21, but the right edge portion 6a and the left edge portion 6b of the top sheet 6 are formed by the wing portions 21 and 21. It only extends to the base of. On both left and right sides, liquid-impermeable sheets 22 formed of a hydrophobic nonwoven fabric or a water-repellent nonwoven fabric are superposed on the outermost surface. The inner edges 22a of the sheets 22, 22 are located at a position that is a predetermined distance from the longitudinal center line Oy-Oy and at a position that is separated from the outer contour line 9B of the crimping portion 9, and the edges 22a The topsheet 6 is exposed in a region sandwiched between the first sheet 22 and the second sheet 22a.
[0132]
The sheets 22, 22 are bonded on the top sheet 6 on both sides, and are bonded to the back sheet 2 at the wing portions 21, 21. That is, the wing portions 21 and 21 are formed by bonding the back sheet 2 and the sheet 22 so that liquid cannot penetrate into these portions.
[0133]
In the sanitary napkin 1C, the liquid-impermeable sheets 22, 22 are provided on both outer sides of the auxiliary absorption region 12, so that lateral leakage such as menstrual blood can be further prevented. Further, by attaching the wing portions 21 and 21 to the outer surface of the crotch portion of the underwear via the pressure-sensitive adhesive layer, the sanitary napkin 1C can be firmly fixed at the crotch portion.
[0134]
In addition, since menstrual blood is unlikely to diffuse from the central absorption region 11 having the liquid guide layer 5 to the periphery beyond the crimping portion 9, low water repellency can be used as the sheets 22, 22, and the wing portions 21, 21 are high. There is no need to make the structure water-repellent. Further, the seats 22 and 22 having a small basis weight can be used. Similarly, even if the wings 21 and 21 have a small basis weight, the fear of lateral leakage does not increase.
[0135]
FIG. 10 is a plan view showing a sanitary napkin 1D which is an absorbent article according to a fifth embodiment of the present invention.
[0136]
The sanitary napkin 1D differs from the above embodiments in the pattern shape of the crimping portion 190, but the other basic structure of the sanitary napkin is the same as that of the first embodiment shown in FIG. Is substantially the same as
[0137]
The crimping portion 190 has a right crimping portion 9a and a left crimping portion 9b and a front crimping portion 9c and a rear crimping portion 9d having substantially the same pattern as the crimping portion 9 shown in FIG. , 9b, 9c, 9d are continuous so as to surround the central absorption region 11, and the liquid guide layer 5 is provided in the central absorption region 11.
[0138]
The crimping portion 190 is formed with a front extension crimping portion 9e extending further forward from the boundary between the right crimping portion 9a and the front crimping portion 9c, and similarly further forward from the boundary between the left crimping portion 9b and the front crimping portion 9c. A front extension crimping portion 9f extending to the front is formed. The front extension crimping portion 9e is located on the extension of the right crimping portion 9a, and the front extension crimping portion 9f is also located on the extension of the left crimping portion 9b. The front extension crimping portion 9e and the front extension crimping portion 9f are inclined away from the longitudinal center line Oy-Oy toward the front edge 1c of the sanitary napkin. The front end of the front extension crimping portion 9f is located away from the front edge 1c, the right edge 1a, and the left edge 1b.
[0139]
In the rear region, a rear extension crimp portion 9g extending further rearward from the boundary between the right crimp portion 9a and the rear crimp portion 9d is formed, and the rear extending further rearward from the boundary between the left crimp portion 9b and the rear crimp portion 9d. An extended crimp portion 9h is formed. The rear extension crimping portion 9g is located on an extension of the right crimping portion 9a, and the rear extension crimping portion 9h is also located on an extension of the left crimping portion 9b. The rear extension crimping portion 9g and the rear extension crimping portion 9h are inclined so as to be away from the longitudinal center line Oy-Oy toward the rear edge 1d of the sanitary napkin. The rear end of the rear extension crimping portion 9h is located away from the rear edge 1d, the right edge 1a, and the left edge 1b.
[0140]
Next, a sanitary napkin 1E according to a sixth embodiment of the present invention shown in a plan view in FIG. 11 has the same structure as the sanitary napkin 1C shown in FIG. It has wings 21 and 21 extending to both left and right sides, and has seats 22 and 22.
[0141]
A crimping portion 190 having the same pattern as that of the sanitary napkin 1D shown in FIG. 10 is formed in a region between the edges 22a of the sheets 22, 22.
[0142]
In the sanitary napkins 1D and 1E, the central absorbent region 11 surrounded by the right crimping portion 9a, the left crimping portion 9b, the front crimping portion 9c and the rear crimping portion 9d, that is, the region provided with the liquid guide layer 5 is illustrated in FIG. As shown in FIG. 5, the central absorbent region 11 is deformed in a convex shape toward the wearer, so that the central absorbent region 11 is easily brought into close contact with the excretory part of the body.
[0143]
Further, in a region ahead of the front crimping portion 9c, the front extension crimping portion 9e and the front extension crimping portion 9f are formed to face each other so as to move away from each other toward the front edge 1c. Therefore, the region sandwiched between the front extension crimping portion 9e and the right side edge 1a and the region sandwiched between the front extension crimping portion 9f and the left side edge 1b define the front extension crimping portion 9e and the front extension crimping portion 9f. It becomes easy to deform in the direction toward the body as a bending starting point. Therefore, the sanitary napkin can be easily fitted to the front part of the crotch part of the body.
[0144]
Similarly, also in the rear region, the region sandwiched between the rear extension crimping portion 9g and the right edge 1a and the region sandwiched between the rear extension crimping portion 9h and the left edge 1b are formed with the rear extension crimping portion 9g and the rear. It becomes easy to deform in the direction toward the body with the extension crimping portion 9h as a bending starting point. Therefore, the sanitary napkin is deformed so as to follow the shape of the buttocks of the body, and it is easy to fit the body.
[0145]
In addition, since the liquid guide layer 5 does not cover the crimping portion 190, it is easy to form the crimping portion 190 in a uniform compressed state.
[0146]
In the embodiments shown in FIGS. 1, 2, 7, 8, and 10, the provision of the liquid guide layer 5 makes it difficult for menstrual blood to diffuse around the area other than the central absorption area 11. Almost the entire surface is formed of a liquid-permeable topsheet, and even if the liquid-impermeable sheets 22 and 22 and the wing portions 21 and 21 are not provided as shown in FIGS. It is easy to prevent menstrual blood from leaking sideways. Also, as in the embodiments shown in FIGS. 1, 2, 7, 9, 10, and 11, a long and wide hip guard portion is not provided particularly at the rear portion as shown in FIG. Even if there is, it is easy to prevent leakage of menstrual blood in the buttocks direction.
[0147]
Further, as the sanitary napkin according to the embodiment of the present invention, as shown in FIGS. 12A and 12B, leak-proof walls 50, 50A extending in the vertical direction are formed on the left and right sides of the skin side surface of the sanitary napkin. Can be configured as
[0148]
The leak-proof walls 50 and 50A are formed by a liquid-impermeable sheet 22. The sheet 22 is folded in two layers, and an elastic member 51 extending in the vertical direction is sandwiched inside the sheet 22. . FIGS. 12A and 12B show a state in which the sanitary napkin is cut along the horizontal reference line Ox, and the two sheets 22 overlap each other at both ends in the longitudinal direction of the sanitary napkin. Are folded and adhered and fixed to the topsheet 6. The elastic member 51 is fixed to the sheet 22 in a state where the elastic member 51 is stretched at a predetermined elongation in the longitudinal direction.
[0149]
Due to the contraction force of the elastic member 51, the sanitary napkin has a curved shape. As a result, the sheet 22 rises in a predetermined range before and after the horizontal reference line Ox, and the leak-proof walls 50 and 50A are formed.
[0150]
By providing the leak-proof walls 50, 50A, lateral leakage of the liquid can be further prevented, and since the sanitary napkin is curved as described above, it becomes easy to fit the crotch portion.
[0151]
The sheet 22 forming the leak-proof walls 50 and 50A may rise from the top sheet 6 as shown in FIG. 12A, or may be lowered together with the top sheet 6 as shown in FIG. It may be attached so as to be caught between the side absorber 3 and the back sheet 2.
[0152]
Next, FIG. 13 shows an example of a manufacturing method for manufacturing the sanitary napkin 1 of the present invention.
[0153]
A nonwoven fabric 101 such as an air-through nonwoven fabric for forming the liquid guide layer 5 is wound around the raw fabric 100. The nonwoven fabric 101 is supplied to the heating unit 103 after passing through the first drive roll 102. The heating unit 103 is provided with a hot air device 104, and hot air 105 is blown against the nonwoven cloth 101 from a hot air port (not shown) of the hot air device 104.
[0154]
The blowing of the hot air 105 restores the bulk of the nonwoven fabric 101. The bulk is restored within a range of 1.5 to 3 times, and the density is also 0.005 g / cm. ³ ~ 0.02g / cm ³ Is recovered. The temperature of the hot air 105 blown from the hot air device 104 is preferably equal to or higher than the softening temperature of the material having the lowest softening temperature among the materials constituting the air-through nonwoven fabric, and the softening of the material having the highest softening temperature. It is more preferred to heat to a temperature above the temperature. Specifically, the heating temperature is in the range of 130C to 300C.
[0155]
The nonwoven fabric 101 whose thickness has been recovered is supplied to the cooling device 107 before, after, or at the same timing as passing through the second drive roll 106. The cooling device 107 blows air from a nozzle 107a, and the nonwoven fabric 101 is rapidly cooled by blowing air. The cooling device 107 may be provided as a pair so as to face both the front and back surfaces of the nonwoven fabric 101.
[0156]
When the non-woven cloth 101 whose bulk has been recovered by heating is cooled, the fibers forming the non-woven cloth 101 are fixed in a short time. Can be. Therefore, even if tension is applied to the non-woven cloth 101 immediately after the subsequent conveyance, the bulk of the non-woven cloth 101 is not crushed, and the bulk can be recovered immediately when the tension is released.
[0157]
In particular, when the nonwoven fabric 101 is an air-through nonwoven fabric formed of thermoplastic fibers, the material constituting the nonwoven fabric becomes a softening temperature or lower by cooling. Therefore, even if the tension is applied, it is possible to prevent the nonwoven cloth 101 from stretching and reducing its bulk.
[0158]
In the case of the transfer device shown in FIG. 13, the rotation speed of the first drive roll 102 provided before the heating unit 103 is equal to the rotation speed of the second drive roll 106 provided after the heating unit 103. Or faster. Since the nonwoven fabric 101 that has passed through the heating unit 103 increases in bulk and contracts in the transport direction, the rotation speed of the second drive roll 106 at the subsequent stage of the heating unit 103 is increased by If the rotation speed of the first drive roll 102 is higher than the rotation speed of the first drive roll 102, the nonwoven fabric 101 receives the tension from the second drive roll 106 even if the bulk thereof is once recovered by the heating unit 103. It is stretched again in the contracted transport direction, and the bulk tends to decrease. Therefore, by making the rotation speed of the second drive roll 106 equal to or slower than that of the first drive roll 102, tension is not applied to the non-woven cloth 101 in the length direction. And a bulky state can be maintained.
[0159]
In addition, it is preferable that the cooling device 107 is provided before the nonwoven fabric 101 is supplied to the second drive roll 106 because the nonwoven fabric 101 can more effectively maintain the state where the bulk has been recovered.
[0160]
The nonwoven fabric 101 whose bulk has been recovered is, for example, stacked as shown in FIG. 3 and then supplied between cutter rolls 108 and 109 and trimmed into a predetermined shape to form the liquid guide layer 5. Is done. The liquid guide layer 5 is sent to the rolls 113 and 114 by being sucked by a conveyor or the like.
[0161]
A nonwoven fabric 111 such as an air-through nonwoven fabric for forming the topsheet 6 is wound around the raw fabric 110. After the non-woven cloth 111 has passed through the roll 112, the non-woven cloth 111 and the liquid guide layer 5 are stacked on each other with the rolls 113 and 114 interposed therebetween and supplied between the liquid-permeation-hole forming rolls 115 and 116. You.
[0162]
A plurality of heated pins are provided on the surface of the roll 115 on the side facing the non-woven cloth 111 forming the topsheet 6 among the rolls for forming the liquid permeable holes, while facing the liquid guide layer 5. The surface of the roll 116 on the side is a flat surface.
[0163]
When the superimposed non-woven cloth 111 and the liquid guide layer 5 are supplied between the liquid permeation forming rolls 115 and 116, the heated pins are stabbed into the non-woven cloth 111, and the heated non-woven cloth 111 is separated from the liquid guide layer. A large number of liquid permeation holes 15 are formed over 5. Since the non-woven cloth 111 and the liquid guide layer 5 contain thermoplastic fibers, the thermoplastic fibers are fused by inserting a heated pin, and the non-woven cloth 111 is The liquid guide layer 5 is adhered to each other. Therefore, it is not necessary to apply an adhesive to the boundary surface between the nonwoven cloth 111 and the liquid guide layer 5, but before passing the nonwoven cloth 111 and the liquid guide layer 5 between the liquid permeable hole forming rolls 115 and 116. In addition, a bonding step of bonding between the nonwoven cloth 111 and the liquid guide layer 5 may be provided.
[0164]
On the surface of the pulp stacking drum 120, a stack of pulp forming the upper absorber 4 and the lower absorber 3 is held in a patterned manner. The pulp laminated body 121 supplied from the pulp laminating drum 120 is placed on a tissue 125 fed from a raw web 123, and is sandwiched between the tissue 125 and a tissue 124 fed from the raw web 122.
[0165]
A hot melt type adhesive is applied to the pulp laminate 121 sandwiched between the tissues 124 and 125 by a nozzle 126 so as to form a corrugated pattern or a spiral pattern. This hot melt adhesive is applied to the outer surface of the tissue 125 covering the pulp constituting the upper absorbent core 4.
[0166]
The pulp laminate 121, the non-woven cloth 111 and the liquid guide layer 5 are supplied while being superposed between the rolls 127 and 128, and the surfaces of the liquid guide layer 5 and the pulp laminate 121 are coated with the hot melt adhesive. The covering tissue 125 is adhered.
[0167]
Further, a laminate comprising the non-woven cloth 111, the liquid guide layer 5, and the pulp laminate 121 wrapped by the tissues 124 and 125 is supplied to embossing rolls 129 and 130 to form the crimping section 9 shown in FIG. You.
[0168]
In the step of forming the crimping portion 9, a flat roll 129 is applied to the outer surface of the tissue 124 covering the pulp laminate 121, and a heating roll 130 having an embossed pattern convex portion is applied to the outer surface of the nonwoven fabric 111, The pulp laminate 121 and the nonwoven fabric 111 are locally pressurized and heated. Further, a hot melt type adhesive is applied to the outer surface of the tissue 124 of the laminate by the nozzle 131.
[0169]
When the moisture-impermeable film 133 forming the back sheet 2 is pulled out from the raw fabric 132, the film 133 and the laminate are pressed and bonded between the rolls 134 and 135, and the film 133 is attached to the skin side surface. Are formed on each other.
[0170]
Then, the laminate is supplied between the cutter rolls 136 and 137, and the sanitary napkin 1 having the shape shown in FIG. 1 is trimmed and cut out.
[0171]
14 to 16 show another example of the heating unit 103. FIG. In FIG. 14, the nonwoven fabric 101 is supplied into the heating device 140. Hot air 141 is blown out into the heating device 140, and the inside of the heating device 140 is uniformly heated. For this reason, in the heating device 140, both the front and back surfaces of the nonwoven fabric 101 are heated, and the bulk of the nonwoven fabric 101 can be more effectively recovered.
[0172]
The heating unit 103 in FIG. 15 includes heating rolls 142 and 143. The non-woven fabric 101 is wound around the heating rolls 142 and 143 and heated.
[0173]
The heating rolls 142 and 143 are separated from each other and have a smooth surface. The nonwoven fabric 101 is conveyed by being wound around the heating rolls 142 and 143 without being pressed between the heating rolls 142 and 143. At this time, one surface of the nonwoven fabric 101 is heated by contacting the surface of the heating roll 142 and the other surface of the nonwoven fabric 101 is heated by contacting the other surface of the nonwoven fabric 101 with the surface of the heating roll 143. The nonwoven fabric 101 is heated from both front and back surfaces by the two heating rolls 142 and 143.
[0174]
In FIG. 16, a rotating drum 145 is provided between the first driving roll 102 and the second driving roll 106. A hot-air device 146 is provided at a predetermined distance from the outer peripheral surface of the rotary drum 145, the surface having a hot-air blowing port curved along the outer peripheral surface of the rotary drum 145. A predetermined space is provided between the hot air device 146 and the rotary drum 145 so that the hot air device 146 does not contact the nonwoven fabric 101 when the nonwoven fabric 101 passes over the rotary drum 135. I have.
[0175]
When the nonwoven cloth 101 passes over the rotary drum 145, hot air 147 is blown against the nonwoven cloth 101 from a hot air blowing port (not shown) provided in the hot air device 146, and the nonwoven cloth 101 is blown. Is restored. It is preferable that the rotating drum 145 itself be heated, because the front and back surfaces of the nonwoven fabric 101 can be heated and the bulk can be effectively recovered.
[0176]
Note that the relationship between the rotational speeds of the first drive roll 102 and the second drive roll 106 and the description of the cooling device 107 are the same as those described with reference to FIG.
[0177]
In addition, the heating unit 103 and the cooling device 107 described above may be provided also in the conveyance path of the nonwoven cloth 111 forming the topsheet 6, and may recover the bulk of the nonwoven cloth 111 together with the nonwoven cloth 101.
[0178]
After the nonwoven cloth 111 and the liquid guide layer 5 are overlapped, the nonwoven cloth 111 and the liquid guide layer 5 may be heated and cooled together.
[0179]
【Example】
(Example A)
Hereinafter, the performance of the example of the absorbent article of the present invention will be described in comparison with a comparative example. In the following Examples and Comparative Examples, sanitary napkins having the structures shown in FIGS. 1 to 4 were prototyped.
[0180]
(Dimensions of each part)
The length of the napkin at the longitudinal centerline is 210 mm, the width at the transverse centerline is 80 mm, the longitudinal dimension L2 at the longitudinal centerline of the central absorbent region is 94 mm, and the transverse dimension W2 at the transverse centerline. Was set to 29 mm.
[0181]
(Crimp condition)
The width Wa was 3 mm, the width dimension δ of the fusion zone 9D was 0.7 mm, and the pitch P was 2.7 mm. The pressure-bonded portion was formed at a temperature of the embossing roll of 120 ° C. and a pressure of 1.76 kPa.
[0182]
(1) Example
As the surface sheet 6, a core is made of polyethylene terephthalate (PET) containing about 1.0% by mass of titanium oxide, and a sheath is made of a core-sheath type composite synthetic fiber of polyethylene (PE) with a fineness of 2.2 dtex and a fiber length of An air-through nonwoven fabric was formed by 44 mm. Of the synthetic fibers, 80% by mass was coated with a hydrophilic oil agent, and 20% by mass was coated with a water-repellent oil agent. Density is 0.083 g / cm ³ And the basis weight is 25g / m ² Met.
[0183]
An air-through nonwoven fabric made of an eccentric core-in-sheath type composite synthetic fiber having a core of polypropylene (PP) and a sheath of polyethylene (PE) having a fineness of 4.4 dtex and a fiber length of 50 mm as the liquid guide layer 5 Was used. 0.042 g / cm density ³ , Basis weight 20g / m ² Was used.
[0184]
The three sheets are folded so as to be stacked, and the topsheet 6 and the liquid guide layer 5 are sandwiched between dies having pins of 110 ° C. and holes of 120 ° C., an opening diameter of 1 m, a pitch Hy = 3.75 mm, and Hx = 2. A liquid permeation hole of 0 mm was formed.
[0185]
The upper absorber 4 is a laminated body of chemical pulp and has a basis weight of, for example, 230 g / m. ² The one having a vertical dimension of 120 mm and a maximum horizontal dimension of 55 mm was used. 160 g / m2 of chemical pulp as lower layer absorber 3 ² And 8 g / m of super absorbent polymer ² A mixture having a vertical dimension of 180 mm and a maximum horizontal dimension of 75 mm was used. In a state where the upper absorber 4 and the lower absorber 3 are overlapped, the surface of the upper absorber 4 and the lower surface of the lower absorber 3 are each weighed 15 g / m 2. ² Was used as an absorbent layer.
[0186]
The back sheet 2 is a liquid-impermeable and air-permeable sheet, and uses a polyethylene (PE) film in which fine air holes are formed.
[0187]
At the interface between the liquid guide layer 5 and the upper absorber 4, a hot-melt type adhesive having a width of 18 mm and a spiral shape of 3 g / m ² Coated and adhered.
[0188]
(2) Comparative example 1
A liquid guide layer 5 having a width of 55 mm and a vertical size of 120 mm was used as the liquid guide layer 5 and a liquid guide layer 5 was sandwiched between the crimping portions 9 to produce a prototype.
[0189]
(3) Comparative example 2
A prototype in which the liquid guide layer 5 of the above embodiment was eliminated was produced. Further, the topsheet 6 is an air-through nonwoven fabric containing no water-repellent fiber, having the same basis weight and the same density as in Example 1, and having only the topsheet 6 with the same liquid permeable holes as in the example. Was.
[0190]
(4) Measurement of liquid diffusion characteristics
As artificial menstrual blood, a solution prepared by adding 300 g of glycerin, 30 g of sodium carboxymethylcellulose, and 40 g of sodium chloride to 4.0 liters of ion-exchanged water, and using red coloring was used.
[0191]
An acrylic plate (115 g of own weight) having a long hole with a vertical hole size of 40 m and a vertical hole size of 10 mm was installed in each of the example and the comparative example. Portions were supplied with the artificial menstrual blood. At an injection rate of 95 ml / min, 3 ml was supplied at the first time, 4 ml was supplied at the second time after the liquid disappeared from the surface, and 3 ml was supplied at the third time after the liquid disappeared from the surface.
Then, the diffusion dimension of the liquid in the lateral direction on the topsheet was measured.
[0192]
(5) Measurement results
The example was 21 mm, the comparative example 1 was 29 mm, and the comparative example 2 was 34 mm.
[0193]
(Example B)
Next, the performance of the liquid guide layer used in the absorbent article will be described in comparison with Examples and Comparative Examples.
[0194]
Air-through nonwoven fabrics of the following Examples 1 to 4 to be used as a liquid guide layer were experimentally produced.
[0195]
(1) Example 1
An eccentric core-in-sheath type composite synthetic fiber with a core of polypropylene (PP) and a sheath of polyethylene (PE), a fineness of 4.4 dtex, a fiber length of 50 mm, and a basis weight of 20 g / m. ² Was formed. This nonwoven fabric was heat-treated in an oven at 135 ° C. for 1 minute to recover the bulk, and then left in an environment at room temperature of 20 ° C. and a relative humidity of 60% for 30 minutes.
[0196]
(2) Example 2
The same air-through nonwoven fabric as in Example 1 was heat-treated in an oven at 145 ° C. for 1 minute, and then left for 30 minutes in an environment at a room temperature of 20 ° C. and a relative humidity of 60%.
[0197]
(3) Example 3
The same air-through nonwoven fabric as in Example 1 was heat-treated in an oven with hot air at 160 ° C. for 1 minute, and then left in an environment at room temperature of 20 ° C. and a relative humidity of 60% for 30 minutes.
[0198]
(4) Example 4
An eccentric core-in-sheath type composite synthetic fiber having a core portion of polyethylene terephthalate (PET) containing 1.1% by mass of the mass of the fiber and a sheath portion of polyethylene (PE) having a fineness of 2.2 dtex and a fiber The length is 44mm and the basis weight is 25g / m ² Was formed. This nonwoven fabric was heat-treated in an oven at 135 ° C. for 1 minute, and then left for 30 minutes in an environment at a room temperature of 20 ° C. and a relative humidity of 60%.
[0199]
(5) Example 5
The same air-through nonwoven fabric as in Example 4 was heat-treated in an oven with hot air at 145 ° C. for 1 minute, and then left in an environment at room temperature of 20 ° C. and a relative humidity of 60% for 30 minutes.
[0200]
(6) Example 6
The same air-through nonwoven fabric as in Example 4 was heat-treated in an oven with hot air at 160 ° C for 1 minute, and then left for 30 minutes in an environment at a room temperature of 20 ° C and a relative humidity of 60%.
[0201]
(7) Comparative example 1
The same air-through nonwoven fabric as in Example 1 was used without heat treatment.
[0202]
(8) Comparative example 2
The same air-through nonwoven fabric as in Example 1 was heat-treated in an oven with hot air at 115 ° C. for 1 minute, and then left in an environment at room temperature of 20 ° C. and a relative humidity of 60% for 30 minutes.
[0203]
(9) Comparative example 3
The same air-through nonwoven fabric as in Example 4 was used without heat treatment.
[0204]
(10) Comparative example 4
The same air-through nonwoven fabric as in Example 4 was heat-treated in an oven with hot air at 115 ° C. for 1 minute, and then left in an environment at room temperature of 20 ° C. and a relative humidity of 60% for 30 minutes.
[0205]
(11) Thickness measurement of the air-through nonwoven fabric of the above example and comparative example
The air-through nonwoven fabrics of the above Examples and Comparative Examples having a size of 100 × 100 mm were used as samples, two acrylic plates of 100 × 200 mm and a mass of 70 g were used, and the samples were sandwiched between two acrylic plates. .
[0206]
With each sample sandwiched between acrylic plates, the thickness of each sample was measured using a UF-60A model thickness gauge manufactured by Daiei Kagaku Seiki Seisakusho. This was defined as the thickness at the time of drying. The thickness measurement is a measurement value one minute after the terminal of the thickness gauge is placed on the acrylic plate, and the same applies hereinafter.
[0207]
Next, each sample was completely immersed in the artificial menstrual blood described in Example A, and then immediately lifted. Thereafter, each sample was sandwiched between the acrylic plates, and the thickness of the sample was measured using the thickness gauge. did. This was defined as the thickness when wet.
[0208]
Next, each sample was completely immersed in the artificial menstrual blood and then immediately pulled up. With the sample sandwiched between the acrylic plates, a 930 g weight was placed on the terminal of the thickness gauge, and a pressure of 980 Pa (10 g / cm ² ), And the thickness of the sample was measured one minute after the terminal of the thickness gauge was placed on the acrylic plate. This was defined as the thickness in a wet state and under pressure.
[0209]
Next, the weight was removed to restore the thickness of the liquid guide layer of each sample, and after 1 minute, the thickness was measured in the same manner. This was taken as the restored thickness.
[0210]
Table 1 shows the thickness when dry, the thickness when wet, and the thickness when pressurized in the wet state.
[0211]
[Table 1]

[0212]
Next, the density was calculated from the thickness under each condition shown in Table 1 and the basis weight of the air-through nonwoven fabric of each sample. Table 2 shows the density when dry, the density when wet, and the density when pressurized in the wet state.
[0213]
[Table 2]

[0214]
(12) Liquid diffusion test
The air-through nonwoven fabrics of Examples 1 to 6 and Comparative Examples 1 to 4 each had a size of 100 × 100 mm, and three layers of the nonwoven fabric were used as a liquid guide layer for measurement.
[0215]
As a surface sheet for measurement, the core portion is an eccentric type core-sheath type composite synthetic fiber of polyethylene terephthalate (PET) containing 1.1% by mass of titanium oxide and the sheath portion is polyethylene (PE), and the fineness is Is 2.2 dtex, the fiber length is 44 mm, and the basis weight is 25 g / m. ² Was used. The top sheet was cut into a width of 100 mm and a length of 200 mm.
[0216]
160 g / m2 of chemical pulp as an absorption layer for measurement ² And 8 g / m of super absorbent polymer ² A mixture of the lower absorbent having a vertical dimension of 180 mm and a width dimension of 75 mm, and a chemical pulp laminate having a basis weight of 230 g / m2. ² A lower absorbent body having a vertical dimension of 120 mm and a width dimension of 55 mm was used. The upper absorber is layered on the lower absorber, and the upper and lower weight is 15 g / m. ² Sand with tissue.
[0217]
The absorption layer, the liquid guide layer, and the topsheet are stacked on an acrylic plate having a width of 100 mm and a length of 200 mm. A long hole having a width of 10 mm and a length of 40 mm was formed at the center of an acrylic plate having a mass of 115 g and a width of 100 mm and a length of 200 mm in the vertical direction. The hole was set to be located in the center of the sample.
[0218]
The artificial menstrual blood was supplied from the slot. The injection speed was 95 ml / min, 3 ml was supplied at the first time, and 4 ml was supplied at the same injection speed for the second time at 30 seconds after the liquid disappeared from the sample surface, and 30 ml after the liquid disappeared from the surface. After a second, 3 ml was fed a third time at the same injection rate.
[0219]
After the third injection, it was confirmed that the liquid had disappeared from the sample surface. After 1 minute, the acrylic plate having a long hole was removed, and the diffusion dimension of the liquid in the lateral direction on the surface sheet was measured. This diffusion dimension was the longest distance in the vertical and horizontal directions.
Table 3 shows the measurement results.
[0220]
[Table 3]

[0221]
As shown in Table 1, each of the liquid guide layers of Examples 1 to 6 had a pressed non-woven fabric thickness of 0.5 mm or more and 1 mm or less in a wet state. The restored thickness of the nonwoven fabric is 1 mm or more and 2 mm or less. Therefore, the diffusion state was measured by stacking three nonwoven fabrics, and the thickness of the liquid guide layer in the wet state was 1.5 to 3 mm, and the restoration thickness was 3 to 6 mm. Moreover, the density at the time of drying of an Example is 0.005-0.02 g / cm. ³ And the density when wet and under pressure is 0.005 g / cm ³ ~ 0.04g / cm ³ It is.
[0222]
【The invention's effect】
As described above, in the present invention, the liquid repeatedly given in a limited range of the central portion of the absorbent article can be rapidly drawn in, the diffusion of the liquid on the topsheet can be prevented, and the liquid to the side can be prevented. Even if there is a shift, this can be quickly absorbed and side leakage can be effectively prevented. In particular, the present invention has a structure in which the central portion can be in close contact with the excretory part of the body, has a good feeling of wearing on the body, and can concentrate liquid at the central portion.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a sanitary napkin according to a first embodiment of the absorbent article of the present invention;
FIG. 2 is a plan view of the sanitary napkin shown in FIG. 1,
FIG. 3 is a cross-sectional view of the sanitary napkin shown in FIGS. 1 and 2 taken along a lateral center line;
4A is an enlarged view of a central absorption region in the cross-sectional view shown in FIG. 3, FIG. 4B is an enlarged view of an auxiliary absorption region,
FIG. 5 is a sectional view showing a deformed state when the sanitary napkin is worn on a body;
FIG. 6 is an enlarged plan view showing an opened state of a liquid permeable hole;
FIG. 7 is a plan view showing a sanitary napkin according to a second embodiment,
FIG. 8 is a plan view showing a sanitary napkin according to a third embodiment;
FIG. 9 is a plan view showing a sanitary napkin having a wing according to a fourth embodiment;
FIG. 10 is a plan view showing a sanitary napkin according to a fifth embodiment;
FIG. 11 is a plan view showing a sanitary napkin according to a sixth embodiment;
FIGS. 12A and 12B are half sectional views of a sanitary napkin provided with a leak-proof wall;
FIG. 13 is a process explanatory view showing one example of a method for producing a sanitary napkin of the present invention,
FIG. 14 is an explanatory view showing another example of the heating unit;
FIG. 15 is an explanatory view showing another example of the heating unit.
FIG. 16 is an explanatory view showing another example of the heating unit;
[Explanation of symbols]
1, 1A, 1B, 1C, 1D, 1E Sanitary napkin
2 Back sheet
3 Lower layer absorber
4 Upper layer absorber
5 Liquid guide layer
6 Surface sheet
9,90,190 crimping part
9a Right crimping part
9b Left side crimping part
9c Front crimping part
9d rear crimping part
9e, 9f Front extension crimping part
9g, 9h Rear extension crimping part
11, 11A, 11B Central absorption region
12, 12A, 12B auxiliary absorption area
15 Liquid permeation hole
102 First drive roll
103 Second drive roll
103,146 heating unit
104 Heating device for bulk recovery
107 Cooling device
142,143 Heating roll for bulk recovery

Claims (9)

In an absorbent article in which an absorbent layer is provided between a back sheet and a liquid-permeable top sheet,
At a position separated from the center line extending in the vertical direction by a predetermined distance on both the left and right sides, a crimping portion in which the topsheet and the absorbent layer are pressed in a concave shape is formed continuously in the vertical direction, and is sandwiched by the crimping portions. The inner side is divided into a central absorption region and an outer peripheral side beyond the crimping portion is an auxiliary absorption region,
In the central absorption region, between the absorption layer having a hydrophilic material and the topsheet, a liquid guide layer having a structure in which fibers are joined to form a void and having a lower density than the absorption layer is provided. Provided, the liquid guide layer is formed in a size that does not hang on the crimping portion,
In the auxiliary absorption region, the absorbent layer is covered with the topsheet. The crimping portion is formed continuously so as to surround a predetermined range, a region surrounded by the crimping portion is the central absorption region, and the liquid guide layer is larger than an area of the central absorption region. 2. The absorbent article according to claim 1, wherein the absorbent article has a small area, and any of its edges is located at a position not covering the crimping portion. The absorption layer includes a lower absorber and an upper absorber that is overlaid on the lower absorber and has a smaller area than the lower absorber and a larger area than the central absorption region. In the part, the topsheet, the lower layer absorber and the upper layer absorber are pressed in a concave shape,
In the auxiliary absorption region, a bulky portion provided with both the lower absorber and the upper absorber is formed in a portion adjacent to the pressure-bonded portion, and a thickness having the lower absorber outside the bulky portion is formed. 3. The absorbent article according to claim 1, wherein a small area is formed. The absorbent article according to any one of claims 1 to 3, wherein a large number of liquid permeable holes are formed from the top sheet to the liquid guide layer in the central absorption region. The absorbent article according to claim 4, wherein the chemical fibers forming the topsheet and the chemical fibers forming the liquid guide layer are heat-sealed around the liquid permeable holes. Fiber density of the dry the liquid guide layer, the absorbent article according to any of claims 1 is 0.02 g / cm ³ or less at 0.005 g / cm ³ or more 5. The liquid guide layer, the absorption of density when given pressure 980Pa in the wet state (10g / cm ^{2) is,} according to claim 6, wherein in the range of 0.005g / cm ³ ~0.04g / cm 3 Goods. The absorbent article according to claim 6, wherein the liquid guide layer is an air-through nonwoven fabric formed of chemical fibers or an air-laid nonwoven fabric containing chemical fibers. The absorbent article according to any one of claims 6 to 8, wherein the liquid guide layer is formed by folding the nonwoven fabric such that a plurality of the nonwoven fabrics are stacked.

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