JP2003128442A - Intermediate film for laminated glass - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an intermediate film for a laminated film, which exhibits excellent deaeration without influence by precladding methods such as press deaeration or vacuum deaeration and is free from moire phenomenon or failures due to the moire phenomenon. SOLUTION: The intermediate film for laminated glass is provided with a large number of embosses composed of carved-line uneven parts at both the surfaces of thermoplastic resin sheets. The uneven parts are individually formed on both the surfaces of the thermoplastic resin sheet at an angle of 25 deg. or less in the longitudinal direction of the intermediate film, the arrangement interval of the uneven part of one surface is 1.25-1.75 times or higher than that of the other surface. The crossing angle between the uneven parts of both the surfaces is 0 deg., or 5 deg. or more.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an interlayer film for laminated glass on which an embossed scribed unevenness is formed.

[0002]

2. Description of the Related Art Laminated glass obtained by sandwiching an interlayer film for laminated glass made of a thermoplastic resin sheet such as a plasticized polyvinyl butyral resin sheet between glass plates and adhering them to each other is a window for automobiles, aircrafts, buildings, etc. Widely used for glass.

In this type of laminated glass, an intermediate film is usually sandwiched between at least two glass plates and either handled through a nip roll (handing degassing method) or put in a rubber bag and suctioned under reduced pressure (vacuum). Deaeration method), the air remaining between the glass plate and the intermediate film is deaerated while preliminarily press-bonded, and then the main press-bonding is performed by heating and pressing in an autoclave, for example. In the above manufacturing process, the degassing property when laminating the glass and the intermediate film is important.

Usually, a large number of embosses consisting of fine concave portions and convex portions are formed on both surfaces of the intermediate film in order to improve deaeration. Examples of the form of the uneven portion include various uneven patterns composed of a large number of convex portions and a large number of concave portions corresponding to these convex portions, and a large number of scored linear convex portions and these convex linear portions. There are various concavo-convex patterns consisting of a large number of engraved concave groove portions that
Various form factors such as size have been disclosed. However, when regular embossing is formed on both surfaces of the intermediate film, a fringed diffraction image generally referred to as a moire phenomenon appears due to the interference of diffraction surfaces with each other. In particular, the moire phenomenon is likely to appear when a grooved portion having an engraved shape that is excellent in deaeration is formed.

The above-mentioned moire phenomenon is not preferable from the aspect of appearance, but it also causes the operator's eyes to be tired due to changes in the interference fringes that are noticeable when cutting the intermediate film or during the work of laminating. There is a problem in that it causes symptoms such as motion sickness, resulting in reduced workability. Further, even in the case of an interlayer film in which embosses arranged regularly are provided on only one side, when working by stacking a plurality of such films, the moire phenomenon still appears, and similarly, workability is deteriorated. There is a problem that it will decrease.

For this reason, for example, Japanese Patent Publication No. 9-50807
No. 8 discloses an intermediate film which eliminates the moire phenomenon by regularly arranging groove shapes in the concavo-convex shape and setting the pattern at each surface to have an intersection angle of 25 degrees or more, more preferably 90 degrees. It is disclosed. In addition, JP-A-200
Japanese Unexamined Patent Publication No. 0-319045 discloses an intermediate film which eliminates the moire phenomenon by forming the embossing arrangement interval on one surface of the intermediate film and the embossing arrangement interval on the other surface to be different. Furthermore, JP 2001-16
Japanese Patent No. 3641 discloses an intermediate film that eliminates the moire phenomenon by setting the intersection angle between the extrusion direction of the intermediate film and the concave groove to be less than 25 degrees.

In the method disclosed in Japanese Patent Publication No. 9-508078, a shape in which a scribe line having a crossing angle of 90 degrees is provided to eliminate the moire phenomenon is transferred by heat using a roll having a scribe line angle of 45 degrees. It is known that However, the larger the engraving angle of the roll, the less easy the transfer becomes. In general, the vertical scored line shape parallel to the longitudinal direction of transfer is the easiest to form, and the horizontal scored line shape requires strict temperature control and high pressure during transfer.

Further, when the interlayer film obtained by each of the above methods is applied to laminated glass, the temperature at the start of degassing in the pre-compression bonding step must be strictly controlled so that the laminated glass structure (eg glass There is a problem that the peripheral edge sealing precedent phenomenon occurs in which the peripheral edge portion of (/ intermediate film / glass) is sealed first, and the deaeration inside the laminated glass structure becomes further insufficient.

As a means for preventing the occurrence of the preceding phenomenon of the peripheral edge seal, the temperature at the start of degassing is controlled by the size of the groove-shaped uneven shape, and when the laminated glass component is pressed at the start of degassing. Prevents the phenomenon of seal advance,
There is also a method to increase the roughness of embossing, but in this case,
There is a problem that the pre-pressing temperature in the pre-pressing step needs to be significantly increased in order to surely seal the peripheral portion of the laminated glass component. Further, if the scribed shapes on both sides of the intermediate film are made parallel from the viewpoint of formability, there is a problem that the self-adhesiveness of the intermediate film becomes high and the handleability of the film deteriorates.

[0010]

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to exhibit excellent deaerating property without being affected by a pre-compression bonding method such as a handling deaeration method or a vacuum deaeration method, and Another object of the present invention is to provide an interlayer film for laminated glass, in which the moire phenomenon does not appear or a defect due to the moire phenomenon does not occur.

[0011]

The interlayer film for laminated glass according to the present invention is a interlayer film for laminated glass in which a large number of embosses formed by scribed irregularities are formed on both surfaces of a thermoplastic resin sheet. In addition, the concavo-convex shape is formed on both surfaces so that the angle is 25 degrees or less with respect to the lengthwise direction of the interlayer film, and the concavo-convex arrangement interval of one surface is smaller than the concavo-convex arrangement interval of the other surface. It is 1.25 to 1.75 times, and the crossing angle of the uneven shapes on both surfaces is 0 degree or 5 degrees or more.

Further, the interlayer film for laminated glass according to a second aspect of the present invention is the intermediate film for laminated glass according to the first aspect, wherein the main groove portion and the main ridge portion are formed on both surfaces of the thermoplastic resin sheet. In the interlayer film for laminated glass on which a large number of scored embosses are formed, the main concave groove portion has a groove shape, and the main convex ridge portion has the main concave groove portion and the main convex ridge portion at the crown. It has a flat surface portion on which finer sub concave portions and sub convex portions are formed, and the ratio (W / of the width (W) of the flat portion of the top of the main convex portion to the arrangement interval (P) of the main convex portions). P) is 20
% Or more.

Further, an intermediate film for laminated glass according to a third aspect of the present invention is the intermediate film for laminated glass according to the first or second aspect, in which the main concave groove portion of the emboss formed on the thermoplastic resin sheet is formed. Groove depth (Rzg) is 10-3
It is characterized in that it is 0 μm.

The thermoplastic resin sheet used for the interlayer film for laminated glass of the present invention is not particularly limited, and examples thereof include plasticized polyvinyl acetal resin sheet, polyurethane resin sheet, ethylene-vinyl acetate resin sheet, ethylene- Examples thereof include thermoplastic resin sheets such as ethyl acrylate-based resin sheets and plasticized vinyl chloride-based resin sheets that have been conventionally used for interlayer films of laminated glass. These thermoplastic resin sheets are excellent in basic performance required as an interlayer film such as adhesiveness, weather resistance, penetration resistance, and transparency, and are preferably used, among which a plasticized polyvinyl butyral resin sheet is typical. A plasticized polyvinyl acetal resin sheet is more preferably used.

The film thickness of the thermoplastic resin sheet is not particularly limited, but may be set appropriately in consideration of the penetration resistance and the like required in the production of laminated glass, like the conventional intermediate film. , 0.2 to 2 mm is preferable.

The interlayer film for laminated glass of the present invention is formed by forming a large number of embosses having scribed irregularities on both surfaces of the thermoplastic resin sheet. The distribution of the embosses may be provided regularly or irregularly.

The shape of the emboss is not particularly limited, and generally, the cross section has a triangular shape, a quadrangular shape, a truncated triangle, a truncated quadrangle or the like, or a head having a mountain shape or a hemispherical shape. From a large number of scored linear ridges (hereinafter referred to as main ridges) and a large number of scored concave groove parts corresponding to these main ridges (hereinafter referred to as main grooved parts) It is preferable that the concave and convex pattern is formed and that the main groove portion is continuous.

In the interlayer film for laminated glass of the present invention, the concavo-convex shape (emboss) is formed on both surfaces so that the angle is 25 degrees or less with respect to the lengthwise direction of the intermediate film, and the concavo-convex shape on one surface is arranged. The spacing is 1.2 of the uneven spacing of the other surface.
It is 5 to 1.75 times, and the crossing angle of the concavo-convex shapes on both surfaces is 0 degree or 5 degrees or more.

In the uneven shape of the surface of the intermediate film,
The ease with which air escapes during degassing in the pre-pressing process between the glass plate and the interlayer film is closely related to the continuity, directionality and smoothness of the concave and convex concave grooves, and The spacing and arrangement do not significantly affect the ease with which air can escape. The relationship between the shape of the main groove and the degassing property is considered as follows. For example, when a mountain-shaped main ridge is provided and a grid-shaped main groove (deaeration passage) is provided, there is no problem when degassing in the direction along the mountain-shaped main ridge, When the air is degassed at right angles to the main ridges, the air is trapped, resulting in poor degassing.

In the present invention, since the concavo-convex shape including the main concave groove portion as the degassing passage is formed such that the angle is 25 degrees or less with respect to the lengthwise direction (degassing direction) of the interlayer film, A passage can be secured and good deaeration can be obtained.

On the other hand, if the main groove portions are arranged in the longitudinal direction on both sides (front and back) of the intermediate film, the moire phenomenon is likely to appear. The moiré phenomenon appears when the intervals and arrangements of the uneven shapes on both surfaces of the interlayer film are the same or when the angles of the main concave groove portions on both surfaces cause a slight deviation, and in particular, the main concave portions on both surfaces of the interlayer film. It becomes the largest when the arrangement and spacing of the grooves are the same.

The inventor has found that the moire phenomenon appears when the angle deviation of the main concave groove portions on both surfaces of the intermediate film is specific, that is, when the angle is more than 0 degree and less than 5 degrees. It was found that the moire phenomenon does not appear when the angle is 0 degree or 5 degrees or more.

The appearance of the moire phenomenon can be considered as follows. FIG. 1 is a schematic view showing the main concave groove portions when the distances between the main concave groove portions on both sides of the interlayer film are equal, and FIG. 2 shows the intervals between the main concave groove portions on both sides of the interlayer film (one interval is different from the other interval). FIG. 6 is a schematic view showing a main groove portion in the case of (1.6 times). In FIG. 1, the shape that appears due to the angular deviation of the main groove portions on both surfaces of the intermediate film becomes a rhombus, and adjacent rhombuses regularly appear, so that the moire phenomenon appears. On the other hand, in FIG. 2, even if the angles of the main grooves on both sides of the interlayer film are slightly deviated, the shape expressed by the main grooves on both sides of the interlayer film becomes a parallelogram, and there is a deviation between adjacent parallelograms. The moire phenomenon does not appear because it occurs and does not look regular.

In the present invention, the arrangement interval of the concavo-convex shape on one surface of the interlayer film is 1.25 times the arrangement interval of the concavo-convex shape on the other surface.
The occurrence of the moire phenomenon can be prevented by setting the cross angle of the uneven shapes on both surfaces of the intermediate film to 0 degrees or 5 degrees or more by setting the ratio to ˜1.75 times.

If the arrangement interval of the uneven shapes on one surface of the intermediate film is less than 1.25 times or more than 1.75 times the arrangement interval of the uneven shapes on the other surface, the arrangement interval of the uneven shapes is increased. The effect of changing the value becomes less, and the appearance of the moire phenomenon cannot be sufficiently prevented.

If the crossing angle of the irregularities on both surfaces of the intermediate film is more than 0 degree and less than 5 degrees, the appearance of the moire phenomenon cannot be sufficiently prevented. Since it is very difficult to mold so that the crossing angle becomes 0 degree and it is economically disadvantageous, it is usually preferable to set it to 5 degrees or more.

On the other hand, the embossed shape (uneven shape) of the intermediate film
Ease of crushing embossing during pre-pressing (crushability)
Is greatly affected by the volume of embossing. The volume of the embossing is determined by the spacing and arrangement of the main ridges, the area of the flat surface of the crown of the main ridges, and the groove depth of the main groove.

That is, the larger the area of the planar portion of the crown of the main ridges forming the emboss and the deeper the groove depth of the main concave groove, the larger the volume of the emboss. Therefore, in the interlayer film for laminated glass of the present invention, as the shape of the main concave groove portion, by making the crown of the main convex strip portion corresponding to the main concave groove portion having a groove shape a planar shape, in other words For example, by making the cross section orthogonal to the direction of extension of the main ridges trapezoidal, the area of the flat surface of the crown of the main ridges increases, and the volume of the embossing increases accordingly. In this case, it is possible to effectively suppress the occurrence of the phenomenon of prior sealing of the peripheral edge of the laminated glass component (for example, glass / intermediate film / glass). Therefore, the air existing in the vicinity of the central portion of the laminated glass component can be effectively degassed in the preliminary pressure bonding step. Further, by increasing the volume of the emboss, the average surface roughness of the emboss can be made relatively small. At the temperature required for peripheral edge sealing in the pre-compression bonding process, the intermediate film is in a sufficiently fluid state, and if the average surface roughness of embossing is relatively small, it is possible to perform sufficient peripheral edge sealing at normal temperature. Becomes

Further, it is preferable that a sub-concave portion and a sub-convex portion, which are finer than the main concave groove portion and the main convex portion, are formed on the planar portion of the crown of the main convex portion constituting the emboss. When the top of the main ridge is flat, the self-adhesiveness of the interlayer film may be improved, but the main groove and the sub-recess that are finer than the main ridge are formed on the flat surface. As a result, the self-adhesiveness of the intermediate film can be suppressed, and the film handleability becomes good.

The interlayer film for laminated glass of the present invention is constructed as described above, and further, the width (W) of the flat portion of the crown of the main ridges with respect to the arrangement interval (P) of the main ridges. It is preferable that the ratio (W / P) is 20% or more.

If the W / P is less than 20%, the effect of improving the volume of embossing and the effect of preventing the occurrence of the phenomenon of leading edge sealing may not be sufficiently obtained. W above
When / P is 100%, the main groove portion is substantially eliminated, so W / P is preferably less than 100%, more preferably 90% or less. Further, the width (W) of the flat portion of the crown of the main ridge portion may be a constant width over the entire area of the interlayer film, or may be a partially different width, that is, a random width.

The groove depth (Rzg) of the main concave groove portion forming the emboss of the present invention is not particularly limited and is preferably 10
˜30 μm, and more preferably 15 to 25 μm. If the groove depth (Rzg) of the main groove portion is less than 10 μm, the volume of the emboss becomes small, and the peripheral edge seal preceding phenomenon of the glass component in the pre-pressing step occurs,
On the contrary, when the groove depth (Rzg) of the main concave groove portion exceeds 30 μm, the volume of the emboss becomes excessively large and a higher temperature is required to perform the peripheral edge sealing of the glass construct in the pre-compression bonding step. Will be needed. By setting the groove depth (Rzg) of the main concave groove portion to 10 to 30 μm, the volume of the emboss becomes an appropriate size, and the peripheral pre-sealing phenomenon of the glass component does not occur, and the pre-bonding temperature is relatively low. Can seal the periphery of the glass construct. Further, the groove depths (Rzg) of the main concave groove portions may all be the same depth or different depths, and the heights of the respective ridge portions corresponding to the main concave groove portions may also be the same. They may all have the same height or different heights.

The groove depth (Rzg) of the main concave groove portion can be easily obtained by data processing a digital signal measured by using a general-purpose surface roughness meter. In the present invention, JIS is used. Groove depth based on the average line of the roughness curve (line set so that the sum of squares of deviations up to the roughness curve is minimized) defined in B-0601 "Surface Roughness-Definition and Display" The thickness was calculated, and the average value of the measured groove depths was defined as the groove depth (Rzg) of the main concave groove portion.

The dimension of the uneven shape of the emboss is not particularly limited, and in general, the arrangement interval (pitch) of the main ridges.
Is preferably 10 to 2000 μm, more preferably 50 to 1000 μm. The length of the bottom of the main ridge is preferably about 30 to 1000 μm.

An embossing roll method, a calendering roll method, a profile extrusion method, etc. are adopted to form unevenness (emboss) on both surfaces of the interlayer film for laminated glass of the present invention, and among them, quantitatively constant. The embossing roll method is preferably used because it is easy to obtain the engraved concave-convex shape (embossing).

The method for producing laminated glass using the interlayer film for laminated glass of the present invention is not particularly limited,
As in the case of a method for producing a normal laminated glass, by sandwiching an interlayer film between at least a pair of glass plates, first performing preliminary pressure bonding to degas and provisionally bond, and then perform main pressure bonding in, for example, an autoclave. The desired laminated glass can be obtained.

For example, when a laminated glass is manufactured by using an intermediate film made of a plasticized polyvinyl butyral resin sheet as an intermediate film for laminated glass, specifically, pre-compression bonding and main compression bonding are performed as follows. I'm fine.

In the pre-compression bonding, an intermediate film is sandwiched between two transparent inorganic glass plates, and this laminated body is passed through a nip roll,
For example, a pressure of about 196 to 980 kPa and a temperature of about 50 to 1
A method of pre-compressing while handling and degassing under conditions of 00 ° C. (handling degassing method), or putting the above laminate in a rubber bag and connecting the rubber bag to an exhaust system to about −53.2 to −9
Vacuum degree of 9.8kPa (absolute pressure about 47.9-1.3k
(Pa), the temperature is raised while suction-decompressing, and pre-compression bonding is performed at a temperature of about 60 to 100 ° C. (vacuum deaeration method).

Then, the pre-press-bonded laminate is subjected to a conventional method using an autoclave or a press, for example, a pressure of about 196 to 1470 kPa and a temperature of about 120 to.
Mainly pressure-bonded at 150 ° C. to produce a laminated glass.

As the glass plate, not only an inorganic glass plate but also an organic glass plate such as a polycarbonate plate or a polymethylmethacrylate plate can be used.
The laminated structure of laminated glass is not limited to the usual three-layer structure composed of glass plate / intermediate film / glass plate, but is, for example, a multilayer structure composed of glass plate / intermediate film / glass plate / intermediate film / glass plate. It may be.

[0041]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail below with reference to Examples, but the present invention is not limited to these Examples.

(Example 1) [Preparation of interlayer film] 100 parts by weight of a polyvinyl butyral resin (average degree of polymerization 1700, residual acetyl group 1 mol%, butyralization degree 65 mol%) was added to triethylene glycol-diene as a plasticizer. 2-Ethylbutyrate (40 parts by weight) was mixed, and the mixture was melt-kneaded by an extruder and extruded in a sheet form from an extrusion die to form a polyvinyl butyral resin sheet having a thickness of 0.76 mm. Then, a pair of embossing rolls (A, a) whose schematic diagrams are shown in Table 1 and FIG.
Was used to prepare an interlayer film for laminated glass having concave grooves on both surfaces of the polyvinyl butyral resin sheet.
In the schematic diagram of FIG. 3, an embossed pattern having a concave-convex concave-convex shape is omitted.

[Preparation of Laminated Glass] Using the interlayer film obtained above, preliminary pressure bonding was carried out by the following two methods (handling degassing method and vacuum degassing method), and then main bonding was carried out to make laminated glass. Was produced. (1) Two transparent float glass plates (length 30 cm,
It is sandwiched between 30 cm in width and 3 mm in thickness, and the protruding portion is cut off, and the obtained laminate is heated in a heating oven so that the temperature of the laminate (pre-bonding temperature) becomes 60 ° C., 70 ° C. and 80 ° C. After heating, it was passed through a nip roll (air cylinder pressure 343 kPa, linear velocity 10 m / min) to perform preliminary pressure bonding. (2) Two transparent float glass plates (30 cm in length, with vacuum degassing interlayer film)
It is sandwiched between 30 cm in width and 3 mm in thickness, the protruding portion is cut out, the obtained laminate is transferred into a rubber bag, the rubber bag is connected to a vacuum system, and the temperature of the laminate (pre-bonding temperature) is 60 ° C. , 80 ° C and 100 ° C at the same time as -79.8 kPa (absolute pressure 21.3 kP
After holding for 10 minutes under the reduced pressure of a), it returned to atmospheric pressure and pre-compression bonding was performed. (3) Main pressure bonding The laminates preliminarily pressure bonded by the methods of (1) and (2) above were respectively held in an autoclave under conditions of a temperature of 140 ° C. and a pressure of 127 kPa for 10 minutes, and then 50 ° C.
The laminated glass was produced by carrying out the main pressure bonding by lowering the temperature to atmospheric pressure.

[Evaluation] Measurement of the average roughness (Rz) and average arrangement interval (Sm) of embossing on each surface of the interlayer film obtained above, observation of appearance of moire phenomenon, bake test of laminated glass Was carried out by the following method. The results are shown in Table 1. (Rz measurement) Digital stylus electric surface roughness meter (P
erthometer S3P) and a surface profile analyzer for the surface roughness meter (SAS-2010, manufactured by Meishin Koki Co., Ltd.)
With the condition that the tip width of the stylus is 5 μm and the facing vertex is 90 degrees,
In accordance with JIS B-0601 "Surface Roughness-Definition and Display", Rz of emboss on each surface of the interlayer film was measured. (Measurement of Sm) Observing with a microscope, the average arrangement interval of embosses on each surface of the interlayer film was measured. (Presence or absence of appearance of moiré phenomenon) The presence or absence of appearance of moiré phenomenon was confirmed by visually observing while slowly and continuously moving the interlayer film. (Bake test of laminated glass) 140 laminated glass
After heating for 2 hours in an oven at ℃, it was taken out and left for 3 hours. The appearance of the laminated glass was visually observed, and the number of bubbles (bubbles) generated in the laminated glass was examined to evaluate the degassing property. The number of test sheets was 100.

Example 2 A laminated glass was prepared and evaluated in the same manner as in Example 1 except that the embossing rolls (B, b) were used. The results are shown in Table 1.

Example 3 A laminated glass was prepared and evaluated in the same manner as in Example 1 except that the embossing rolls (C, c) were used. The results are shown in Table 1.

Comparative Example 1 A laminated glass was prepared and evaluated in the same manner as in Example 1 except that the embossing rolls (D, d) were used. The results are shown in Table 2.

Comparative Example 2 A laminated glass was prepared and evaluated in the same manner as in Example 1 except that the embossing rolls (E, e) were used. The results are shown in Table 2.

Comparative Example 3 A laminated glass was prepared and evaluated in the same manner as in Example 1 except that the embossing rolls (F, f) were used. The results are shown in Table 2.

[0050]

[Table 1]

[0051]

[Table 2]

(Examples 4 to 6 and Comparative Example 4)
And Comparative Example 5)

In order to give various embossed shapes,
Various embossing rolls were prepared (described in Table 3). As the thermoplastic resin sheet, an RZN film (plasticized polyvinyl butyral resin sheet, manufactured by Sekisui Chemical Co., Ltd.) having a flat portion in which various convex and concave portions were formed on the top of the main ridge was prepared. A pair of rolls consisting of an embossing roll and a rubber roll was used as a concavo-convex shape transfer device, and the RZN film was passed through the concavo-convex shape transfer device under the following transfer conditions to produce an intermediate film for laminated glass having embossed shapes on both sides. [Transfer conditions] Temperature of RZN film: normal temperature, transfer temperature of sub-uneven portion of RZN film: 130 ° C, embossing roll temperature: 130
° C, linear velocity: 10 m / min, press linear pressure: 500 kPa

Regarding the interlayer films for laminated glass obtained in Examples 4 to 6 and Comparative Examples 4 and 5,
In the same manner as in Example 1, Rz of emboss on each surface of the interlayer film was measured. Also, the width of the main convex streak and the width of the main concave groove of the emboss on each surface of the intermediate film were measured by observing with a microscope, and W / P was calculated by the following formula. Further, the presence or absence of the appearance of the moire phenomenon was confirmed by the same method as described above. The results are shown in Table 3. W / P (%) = 100 × (width of main ridge-width of main groove) / width of main ridge

Using the intermediate film obtained above, Example 1
In the same manner as above, preliminary pressure bonding was performed by the following two methods (handling degassing method and vacuum degassing method), and then main pressure bonding was performed to produce a laminated glass. However, in the vacuum degassing method, the initial temperature of the rubber bag was 25 ° C, 35 ° C and 45 ° C.

Then, the laminated glass obtained above was
After heating in an oven at 40 ° C for 2 hours, remove and
Left for hours. The appearance of the laminated glass was visually observed, and the number of bubbles (bubbles) generated in the laminated glass was examined to evaluate the degassing property. The number of test sheets was 100. The results are shown in Table 3.

[0057]

[Table 3]

(Examples 7 to 9 and Comparative Example 6)
And Comparative Example 7)

In order to give various embossed shapes,
Various embossing rolls were prepared (described in Table 4). As the thermoplastic resin sheet, an RZN film (plasticized polyvinyl butyral resin sheet, manufactured by Sekisui Chemical Co., Ltd.) having a flat portion in which various convex and concave portions were formed on the top of the main ridge was prepared. A pair of rolls consisting of an embossing roll and a rubber roll was used as a concavo-convex shape transfer device, and the RZN film was passed through the concavo-convex shape transfer device under the following transfer conditions to produce an intermediate film for laminated glass having embossed shapes on both sides. [Transfer conditions] Temperature of RZN film: normal temperature, transfer temperature of sub-uneven portion of RZN film: 130 ° C, embossing roll temperature: 130
° C, linear velocity: 10 m / min, press linear pressure: 500 kPa

Regarding the interlayer films for laminated glass obtained in Examples 7 to 9 and Comparative Examples 6 and 7,
The groove depth (Rzg) of the main groove portion is a digital stylus electric surface roughness meter (Perthometer S3P).
And a surface shape analyzer for the surface roughness meter (SAS-20
10, manufactured by Meishin Koki Co., Ltd.), the measurement was performed under the conditions of a tip width of the stylus of 5 μm and a facing apex of 90 °.
Calculate the groove depth based on the average line of the roughness curve (line set to minimize the sum of squares of deviations to the roughness curve) specified in "Surface Roughness-Definition and Display" Then, the average value of the measured groove depths was used as the groove depth (Rzg) of the main groove portion. Also, the width of the main convex streak and the width of the main concave groove of the emboss on each surface of the intermediate film were measured by observing with a microscope, and W / P was calculated by the following formula. Further, the presence or absence of the appearance of the moire phenomenon was confirmed by the same method as described above. The results are shown in Table 4. W / P (%) = 100 × (width of main ridge-width of main groove) / width of main ridge

Using the intermediate film obtained above, Example 1
In the same manner as above, preliminary pressure bonding was performed by the following two methods (handling degassing method and vacuum degassing method), and then main pressure bonding was performed to produce a laminated glass. However, in the vacuum degassing method, the initial temperature of the rubber bag was 40 ° C, 50 ° C and 60 ° C.

Then, the laminated glass obtained above was
After heating in an oven at 40 ° C for 2 hours, remove and
Left for hours. The appearance of the laminated glass was visually observed, and the number of bubbles (bubbles) generated in the laminated glass was examined to evaluate the degassing property. The number of test sheets was 100. The results are shown in Table 4.

[0063]

[Table 4]

[0064]

As described above, since the interlayer film for laminated glass according to the present invention has the concave-convex concave-convex shapes at specific positions on both surfaces of the interlayer film, it can be handled by a degassing method or vacuum degassing method. Expressing excellent deaeration without being affected by the pre-compression bonding method such as the air method, and the moire phenomenon does not appear, or
It is an interlayer film for laminated glass that does not cause defects due to the moire phenomenon.

[Brief description of drawings]

FIG. 1 is a schematic view of main concave groove portions when the intervals of the main concave groove portions on both surfaces of an intermediate film are equal.

FIG. 2 is a schematic view of main concave groove portions when the intervals of the main concave groove portions on both surfaces of the intermediate film are different.

FIG. 3 is a schematic view of a pair of rolls used in Example 1.

FIG. 4 is a schematic view of a pair of rolls used in Example 2.

5 is a schematic view of a pair of rolls used in Example 3. FIG.

FIG. 6 is a schematic view of a pair of rolls used in Comparative Example 1.

7 is a schematic diagram of a pair of rolls used in Comparative Example 2. FIG.

[Explanation of symbols]

11 Main concave groove on one surface 12 Main concave groove on the other surface 13 Main concave groove on one surface 14 Main concave groove on the other surface θ angle w Engraved line spacing

Claims (3)

[Claims] 1. An interlayer film for laminated glass, comprising a thermoplastic resin sheet having a large number of embossed concave and convex lines formed on both sides thereof, and having an angle of 25 with respect to the longitudinal direction of the interlayer film.
The unevenness is formed on both surfaces so that the unevenness is not more than 1.25 degrees, the arrangement interval of the uneven shapes on one surface is 1.25 to 1.75 times the arrangement interval of the uneven shapes on the other surface, and the unevenness on both surfaces is An interlayer film for laminated glass, wherein the crossing angle of the shape is 0 degree or 5 degrees or more. 2. An interlayer film for laminated glass, comprising a thermoplastic resin sheet, on both sides of which a large number of scored line-shaped embossings consisting of main concave grooves and main convex stripes are formed, wherein the main concave grooves have a groove shape. The main ridge portion has a flat surface portion in which a sub-recess and a sub-projection finer than the main groove portion and the main ridge portion are formed on the crown, and the arrangement interval of the main ridge portions ( The ratio (W / P) of the width (W) of the flat surface of the main ridge portion to P) is 20%.
It is above, The interlayer film for laminated glasses of Claim 1 characterized by the above-mentioned. 3. The interlayer film for laminated glass according to claim 1, wherein the groove depth (Rzg) of the main groove portion of the emboss formed on the thermoplastic resin sheet is 10 to 30 μm.