JPWO2008026749A1 - Non-contact type rewritable recording medium and IC tag using the same - Google Patents

Abstract

Non-contact type capable of recording / erasing with laser light, in which a reversible thermosensitive coloring layer (2) is provided on the surface of the support (1), and a laminate material (6 and 9) is laminated on the reversible thermosensitive coloring layer. A rewritable recording medium, wherein the laminating material has a laser beam transmittance of 80% or more, a non-contact type rewritable recording medium, and an adhesion to the surface of the support opposite to the side on which the laminating material is laminated Rewrite thermal label (15) having an agent layer (4), and a rewrite obtained by bonding the label so that the surface of the adhesive layer faces a non-contact type invisible information read / write IC tag (10) Non-contact IC tag with thermal label (20). While maintaining repetitive recording and erasing performance using laser light, the rewriting durability (heat destructive resistance) can be remarkably improved, and adhesion to printing ink is improved to give good printability, and Image storability can be improved in terms of solvent resistance and light resistance.

Description

  The present invention relates to a non-contact type rewritable recording medium, a rewrite thermal label using the same, a non-contact type IC tag with a rewrite thermal label, and a recording / rewriting method. More specifically, the present invention can remarkably improve the rewriting durability (heat-resistant destruction property) while maintaining the repetitive recording / erasing performance using a laser beam, and is suitable for printing, solvent resistance, and light resistance. A rewritable recording medium that can automatically perform writing and / or erasing of visible information in a non-contact state using laser light without human intervention, which can improve image storage stability with Non-contact type recordable / rewritable adhesive label (hereinafter referred to as “rewrite thermal label”), non-contact type IC tag with rewrite thermal label, and non-contact state for both invisible information and visible information using this IC tag The present invention relates to a recording / rewriting method for automatically erasing or writing information.

Labels currently used for the management of goods, such as labels attached to plastic containers that transport food, labels used for the management of electronic parts, logistics management labels attached to cardboard, etc. What used thermal paper etc.) as a surface base material has become the mainstream.
This heat-sensitive recording material is provided with a heat-sensitive recording layer mainly comprising an electron-donating usually colorless or light-colored dye precursor and an electron-accepting developer on a support. By heating with, for example, the dye precursor and the developer react instantaneously to obtain a recorded image. In general, once such an image is formed, such a heat-sensitive recording material cannot be erased and returned to the state before image formation again.
Until now, in the label used for the above-mentioned article management, such a heat-sensitive recording material has been mainly used as a surface base material, and a contact type thermal printer or the like is used to address, sender, article name, quantity, weight. In addition, information such as date of manufacture, expiration date, unique identification number, lot number, etc., and bar codes of these were printed and affixed to the adherend. When the role as a label is completed, it takes a lot of time and labor to manually peel off the label in order to reuse the container and cardboard as the adherend. In addition, the adherend from which the label has been peeled is affixed again with another label and used repeatedly.
As described above, every time the adherend is repeatedly used, the label is peeled off and pasted. For this reason, attention has been paid to rewritable thermal labels capable of repeatedly recording and erasing information while being attached to the adherend without removing the label from the adherend each time. A non-contact type reversible thermosensitive recording material having a visible information recording / erasing means provided with a thermosensitive coloring layer containing a developer has been developed.
However, when recording visible information that can be written and / or erased in a non-contact manner using a laser beam is repeated a plurality of times, there is a problem that the surface of the recording medium is thermally destroyed by the repeatedly irradiated laser beam. It was. Although the destruction state can be reduced by using a light absorption heat conversion material, it has not yet been completely solved. Also, in addition to variable information thermal color recording, when printing fixed information and colors of each color using a printing method, the adhesion (adhesiveness) between the printing ink and the thermal recording layer may be poor, and printing may not be possible. There was also a problem.
JP 2003-118238 A JP 2002-215038 A JP 2000-6271 A Japanese Patent Laid-Open No. 2000-347569 JP 2004-94510 A JP 2004-102432 A

Under such circumstances, the present invention can remarkably improve the rewriting durability (heat fracture resistance) while maintaining repetitive recording / erasing performance using a laser beam, and has an adhesion ratio to printing ink. The laser light can be written and / or erased without human intervention, improving the image quality and improving the image storage stability in terms of solvent resistance and light resistance. It is an object of the present invention to provide a rewritable recording medium that can be automatically used in a non-contact state, and an application of the recording medium to an adhesive label or a non-contact type IC tag.
As a result of intensive research to achieve the above object, the present inventors have laminated a reversible thermosensitive coloring layer provided on the support surface with a laminate material having a laser beam transmittance of a certain value or more. , It can be rewritten without reducing the recording speed, and it can be found that it can provide the amount of heat necessary for color development and erasure of the thermosensitive coloring layer located below it, and the visual information recorded on the thermosensitive coloring layer of the recording medium can be visually confirmed. It has been found that it is preferable to use a laminate material in which the visible light transmittance is a certain value or more in consideration of the property and the bar code readability. In addition, from the light absorption characteristics of the laminate material, as the base film satisfying each of the above-mentioned transmittances, the heat of the recording medium surface during repeated recording can be obtained by using a polyester resin film or a vinyl chloride resin film. It has been found that destruction can be suppressed.
Furthermore, by providing an ink-receiving layer on one or both sides of the laminate material, it is possible to obtain good adhesion even with printing inks that could not be printed due to poor adhesion with conventional heat-sensitive color developing layers, and laminate the laminate material As a result, it has been found that it contributes to protection from external factors such as solvent resistance and light resistance, which are difficult with conventional recording media, and can significantly improve the image storage stability of the recording media.
In addition, a rewritable thermal label can be obtained by providing an adhesive layer on the surface of the support opposite to the side on which the laminate material of the recording medium is laminated, and the adhesive layer surface of the rewritable thermal label is not contacted. By attaching an IC tag that can read and write invisible information with a mold, the reader / writer can read information in a non-contact state with respect to both the invisible information of the IC tag and the visible information recorded by laser light on the surface. It has been found that a non-contact IC tag with a rewrite thermal label that can be automatically erased or written is obtained.
The present invention has been completed based on such findings.
That is, the present invention
[1] A non-contact type rewritable recording medium which is provided with a reversible thermosensitive coloring layer on the surface of a support and a laminate material is laminated on the reversible thermosensitive coloring layer and which can be recorded / erased by laser light, A non-contact type rewritable recording medium, wherein the laminating material has a laser beam transmittance of 80% or more,
[2] The non-contact type rewritable recording medium according to the above [1], wherein the visible light transmittance of the laminate material is 80% or more,
[3] The above-mentioned [1] or [2], wherein the light-absorbing heat conversion layer is contained in the reversible heat-sensitive color forming layer, or the light-absorbing heat conversion layer having the light-absorbing heat conversion agent is provided on the reversible heat-sensitive color forming layer. ] Non-contact type rewritable recording medium according to item
[4] The above [1] to [1], wherein the laminate material is a base film provided with an adhesive layer, the glass transition temperature of the base film is 60 ° C. or higher, and the melting point is 150 ° C. or higher. [3] The non-contact type rewritable recording medium according to any one of items [1] to [3].
[5] The above [1] to [4], wherein the laminate material is a base film provided with an adhesive layer, and the base film is a polyester resin film or a vinyl chloride resin film. The non-contact type rewritable recording medium according to any one of items
[6] The non-contact type rewritable recording medium according to any one of [1] to [5] above, wherein the wavelength of the laser beam is 700 to 1400 nm,
[7] The non-contact type rewritable recording medium according to any one of [1] to [6] above, wherein an ink receiving layer is provided on at least one surface of the base film of the laminate material,
[8] The non-contact type according to any one of the above [1] to [7], wherein the laminate material has a printing layer on the substrate film or on the surface of the ink receiving layer provided on the substrate film. Rewritable recording medium,
[9] The non-contact type rewritable recording medium according to any one of [1] to [6] above, having a printing layer on the surface of the reversible thermosensitive coloring layer or light absorption heat conversion layer,
[10] An adhesive layer is provided on the surface of the support opposite to the side on which the laminate material of the non-contact type rewritable recording medium according to any one of [1] to [9] is laminated. Rewrite thermal label featuring
[11] The non-contact type recordable rewritable adhesive label according to the above [10] is bonded so that the surface of the adhesive layer faces the non-contact type invisible information read / write IC tag. Using the characteristic non-contact IC tag with a rewrite thermal label and [12] the non-contact IC tag with a rewrite thermal label according to the above [11], each IC tag is read by a reader / writer in the middle of transportation. A recording and rewriting method characterized by automatically performing erasure or writing of information repeatedly in a non-contact state for both invisible information and visible information recorded by laser light on the surface,
Is to provide.

  FIG. 1 is an image diagram of an example of the rewrite thermal label of the present invention, FIG. 2 is an image diagram of an example of the RWT-IC tag of the present invention, FIG. 3 is an image diagram of an example of an article management system using the RWT-IC tag of the present invention, FIG. 4 (a), FIG. 4 (b) and FIG. 4 (c) is an explanatory view showing a test method in Example 5. FIG. In the figure, reference numeral 1 is a support, 2 is a thermosensitive coloring layer, 3 is a light-absorbing heat conversion layer, 4, 9 and 11 are adhesive layers, 5 and 12 are release sheets, 6 is a substrate film for laminating, and 7 is Ink receiving layer, 8 printed layer, 10 IC tag, 13 adherend (managed article), 15 rewrite thermal label, 20 RWT-IC tag, 21 conveyor, 22 managed object, 24 RWT -IC tag reader / writer, 34 is a laser head for recording / erasing visible information, 35 is a member for recording / erasing invisible information, and 37 is an interdigital curtain.

First, the non-contact type rewritable recording medium of the present invention (hereinafter sometimes simply referred to as a recording medium) will be described.
The recording medium of the present invention has a structure in which a reversible thermosensitive coloring layer is provided on the surface of a support, and a laminate material is laminated on the reversible thermosensitive coloring layer.
In the recording medium of the present invention, the support is not particularly limited. For example, polystyrene, acrylonitrile / butadiene / styrene resin, polycarbonate, polypropylene, polyethylene, polyethylene terephthalate, polyethylene naphthalate and other plastic films, synthetic paper, nonwoven fabric, paper, and the like. Is mentioned. Although there is no restriction | limiting in particular as thickness of a support body, Usually, 10-500 micrometers, Preferably it is the range of 20-200 micrometers. If a plastic film is used as the support, it may be subjected to surface treatment by an oxidation method or an unevenness method, if desired, for the purpose of improving the adhesion with an anchor coat layer or an adhesive layer provided on the surface. Can do. Examples of the oxidation method include corona discharge treatment, chromic acid treatment (wet), flame treatment, hot air treatment, ozone / ultraviolet irradiation treatment and the like, and examples of the unevenness method include sand blast method and solvent treatment method. Is mentioned. These surface treatment methods are appropriately selected depending on the type of the support, but in general, the corona discharge treatment method is preferably used from the viewpoints of effects and operability.
It is also effective to use a foam film having a high heat insulating effect as a support in order to effectively use the heat at the time of recording information by laser light. Further, as the support, a plastic film excellent in repeated use suitability is preferable.
An anchor coat layer can be provided on one surface of the support. This anchor coat layer is intended to improve the adhesion between the thermosensitive coloring layer and the support, and to protect the support from the solvent in the coating solution used when providing the thermosensitive coloring layer in the next step. Yes, by providing this anchor coat layer, a support having poor solvent resistance can be used.
There is no restriction | limiting in particular as resin which comprises this anchor coat layer, Although various things can be used, Crosslinked resin excellent in solvent resistance is used suitably. Examples of the crosslinked resin include an acrylic resin, a polyester resin, a polyurethane resin, and an ethylene-vinyl acetate copolymer that can be crosslinked. When a support having poor solvent resistance is used, it is preferable to use a coating solution that is not an organic solvent type, such as an aqueous solution type or a water dispersion type coating solution, for forming the anchor coat layer. Moreover, there is no restriction | limiting in particular as a crosslinking method, According to the kind of resin to be used, it can select suitably from conventionally well-known various methods.
Furthermore, it is also effective to use a resin that crosslinks and cures with ionizing radiation such as ultraviolet rays and electron beams as a solventless type. This ionizing radiation curable resin can easily adjust the crosslinking density by changing the irradiation dose, and can form a crosslinked resin having a high crosslinking density.
The reversible thermosensitive coloring layer provided on the surface of the support is generally composed of a colorless or light dye precursor, a reversible developer, and a binder, a decoloring accelerator, an inorganic pigment, various additives and the like used as necessary. It is configured.
There is no restriction | limiting in particular as said dye precursor, Arbitrary things can be suitably selected and used from the well-known compound used as a dye precursor in the conventional heat-sensitive recording material. For example, 3,3-bis (4-dimethylaminophenyl) -6-dimethylaminophthalide, 3- (4-dimethylaminophenyl) -3- (1,2-dimethylindol-3-yl) phthalide, 3- ( Triarylmethane compounds such as 4-diethylamino-2-ethoxyphenyl) -3- (1-ethyl-2-methylindol-3-yl) -4-azaphthalide, rhodamine B anilinolactam, 3- (N-ethyl) Xanthene compounds such as -N-tolyl) amino-6-methyl-7-anilinofluorane, diphenylmethanes such as 4,4'-bis (dimethylaminophenyl) benzhydrylbenzyl ether, N-chlorophenylleucooramine Compounds, spiro compounds such as 3-methylspirodinaphthopyran, 3-ethylspirodinaphthopyran One type may be selected from thiazine compounds such as benzoyl leucomethylene blue and p-nitrobenzoyl leucomethylene blue, and two or more types may be selected and used in combination.
On the other hand, the reversible developer is not particularly limited as long as it causes a reversible color change in the dye precursor due to the difference in the cooling rate after heating. From the viewpoint of repeated durability, an electron-accepting compound composed of a phenol derivative having a long-chain alkyl group is preferable.
The phenol derivative may have an atom such as oxygen or sulfur or an amide bond in the molecule. The length and number of alkyl groups are selected in consideration of the balance between decoloring properties and color developability, but the alkyl groups are preferably those having 8 or more carbon atoms, particularly those having about 8 to 24 carbon atoms. In addition, hydrazine compounds, anilide compounds, urea compounds having a long-chain alkyl group in the side chain can also be used.
Examples of such a phenol derivative having a long chain alkyl group include 4- (N-methyl-N-octadecylsulfonylamino) phenol, N- (4-hydroxyphenyl) -N′-n-octadecylthiourea, N— (4-hydroxyphenyl) -N′-n-octadecylurea, N- (4-hydroxyphenyl) -N′-n-octadecylthioamide, N- [3- (4-hydroxyphenyl) propiono] -N′-octa Examples include decanohydrazide, 4′-hydroxy-4-octadecylbenzanilide.
Utilizing the crystallinity of such a reversible developer, when recording information, it is rapidly cooled after heating. Recording and erasing are possible.
Examples of the binder used as necessary for the purpose of maintaining each component constituting the thermosensitive coloring layer and maintaining uniform dispersibility include polyacrylic acid, polyacrylic acid ester, polyacrylamide, and polyvinyl acetate. And polymers such as polyurethane, polyester, polyvinyl chloride, polyethylene, polyvinyl acetal, and polyvinyl alcohol, and copolymers of monomers constituting them.
Further, as a decoloring accelerator used as necessary, for example, ammonium salts and the like, as inorganic pigments, for example, talc, kaolin, silica, titanium oxide, zinc oxide, magnesium carbonate, aluminum hydroxide, and the like are added. Examples of the agent include known leveling agents and dispersants.
In order to form the thermosensitive coloring layer, first, a coating liquid is prepared by dissolving or dispersing the dye precursor, the reversible developer, and various additive components used as necessary in an appropriate organic solvent. . In this case, for example, alcohols, ethers, esters, aliphatic hydrocarbons, and aromatic hydrocarbons can be used as the organic solvent. Tetrahydrofuran is particularly preferable because of its excellent dispersibility. Although there is no restriction | limiting in particular about the ratio of a dye precursor and a reversible developer, A reversible developer is 50-700 mass parts normally with respect to 100 mass parts of dye precursors, Preferably it is 100-500 mass parts. Used in a range.
Next, the thus-prepared coating solution is applied by a conventionally known means and dried to form a thermosensitive coloring layer. Although there is no restriction | limiting in particular about drying process temperature, It is desirable to dry at low temperature so that a dye precursor may not color. The thickness of the thermosensitive coloring layer thus formed is usually in the range of 1 to 10 μm, preferably 2 to 7 μm.
In the rewritable recording medium of the present invention, a light-absorbing heat converting agent may be contained in the heat-sensitive color forming layer thus formed, or a light-absorbing heat converting layer may be provided on the heat-sensitive color developing layer. Good.
The light-absorbing heat converting agent has an action of absorbing irradiated laser light and converting it into heat, and is appropriately selected depending on the laser light to be used. As the laser light, it is preferable to select one having an oscillation wavelength in the range of 700 to 1400 nm from the viewpoints of simplicity of the apparatus and scanability. For example, semiconductor laser light and YAG (FAYb) laser light are preferable. .
The light absorbing heat converting agent preferably absorbs near-infrared laser light and generates heat, and does not absorb much light in the visible light region. When the light-absorbing heat converting agent absorbs visible light, the visibility and barcode readability of the rewritable recording medium of the present invention are lowered. Examples of the light absorption heat conversion agent satisfying such required performance include organic dyes and / or organometallic dyes. Specifically, at least one selected from cyanine dyes, phthalocyanine dyes, anthraquinone dyes, azulene dyes, squarylium dyes, metal complex dyes, triphenylmethane dyes, indolenine dyes, and the like. Can be mentioned. Of these, indolenine dyes are preferred because of their high photothermal exchange properties.
When the light-absorbing heat converting agent is contained in the thermosensitive coloring layer, the content thereof is not particularly limited, but is usually 0.1 to 30% by mass, preferably 0.2 based on the total mass of the thermosensitive coloring layer. -10 mass%, More preferably, it is 0.5-5 mass%.
On the other hand, when a light absorption heat conversion layer is provided on the thermosensitive coloring layer, the light absorption heat conversion layer is generally composed of the light absorption heat conversion agent, a binder, and an inorganic pigment, an antistatic agent, etc. Consists of additives and the like.
As the binder, the same materials as those exemplified as the binder in the heat-sensitive coloring layer can be used, but the light-absorbing heat conversion layer is required to have transparency for visualizing the coloring of the lower layer. . Therefore, as the binder, a cross-linked resin is preferable, and an ionizing radiation curable resin such as an ultraviolet ray or an electron beam is particularly preferable.
In order to form this light absorption heat conversion layer, first, a coating liquid containing the light absorption heat conversion agent, a binder, and various additives used as necessary is prepared. At this time, depending on the type of the binder, an appropriate organic solvent may be used as necessary. Although there is no restriction | limiting in particular about the ratio of a binder and a light absorption heat conversion agent, A light absorption heat conversion agent is 0.01-50 mass parts normally with respect to 100 mass parts of binders, Preferably it is 0.03-10 mass parts. Used in a range. However, since the light absorption heat conversion agent may also absorb light in the visible light range, if the amount of the light absorption heat conversion agent is large, the light absorption heat conversion layer may be colored. When the light-absorbing heat conversion layer is colored, the light-absorbing heat-converting agent is taken into consideration not only the appearance of the recording medium but also the information visibility and barcode readability in consideration of the balance with the color development sensitivity due to heat generation It is preferable to keep the blending amount of the above small.
Next, the coating solution thus prepared is coated on the thermosensitive coloring layer by a conventionally known means, and after drying treatment, it is crosslinked by heating, irradiation with ionizing radiation, etc., thereby absorbing light. A heat conversion layer is formed. The thickness of the light absorption heat conversion layer thus formed is usually 0.05 to 10 μm, preferably 0.1 to 3 μm.
In the rewritable recording medium of the present invention, a laminate material is laminated on the heat-sensitive color developing layer, the heat-sensitive color developing layer containing the light absorbing heat converting agent, or the light absorbing heat converting layer. At this time, printing may be performed in advance on the layer on which the laminate material is laminated, and then the laminate material may be laminated, or on the base film of the laminate material or on the ink receiving layer provided on the base film Can also be printed.
As the laminate material used in the present invention, for example, a material provided with an adhesive layer on one surface of a base film is used.
The base material film of the laminate material satisfies the requirement that the laser beam transmittance of the laminate material is 80% or more, and the visible light transmittance is preferably 80% or more. Any film may be used as long as it is made of a material that is unlikely to occur, and any film can be used, but it is preferable that the glass transition temperature is 60 ° C. or higher and the melting point is 150 ° C. or higher. When the glass transition temperature is less than 60 ° C. or the melting point is less than 150 ° C., there is no durability against repeated heat history of laser light irradiation, resulting in hue change and shape change (bulge or dent) on the surface of the laminate material. Besides causing poor appearance, it may cause irregular reflection of the laser beam and cause recording and erasure defects. From this viewpoint, a polyester resin film and a vinyl chloride resin film that are less likely to be thermally destroyed by laser light are suitable, and a fluorine resin film or the like can also be used.
Examples of the polyester resin that is a material of the polyester resin film include polyethylene terephthalate resin, polyethylene naphthalate resin, and polybutylene terephthalate resin. Among these, performance and economy From the viewpoint of balance such as polyethylene terephthalate resin is preferable. Examples of the polyethylene terephthalate resin include polyethylene terephthalate resin, isophthalic acid-modified polyethylene terephthalate resin, and cyclohexanedimethanol-modified polyethylene terephthalate resin.
On the other hand, examples of the vinyl chloride resin that is a material of the vinyl chloride resin film include polyvinyl chloride having a number average degree of polymerization of about 800 to 2500 and a copolymer mainly composed of vinyl chloride (for example, ethylene-vinyl chloride copolymer). Polymers, vinyl acetate-vinyl chloride copolymers, vinyl chloride-halogenated olefin copolymers, etc.) or other compatible resins based on these polyvinyl chloride or vinyl chloride copolymers (eg polyester resins). , Epoxy resin, acrylic resin, vinyl acetate resin, urethane resin, acrylonitrile-styrene-butadiene copolymer, partially saponified polyvinyl alcohol, and the like. These vinyl chloride resins may be used alone or in combination of two or more.
As this vinyl chloride-based resin, a resin blended with about 0 to 70 parts by mass of a plasticizer is usually used with respect to 100 parts by mass.
In these base films, various additives such as heat stabilizers, antioxidants, weathering agents, ultraviolet absorbers, mold release agents, lubricants, antistatic agents are optionally added as long as the object of the present invention is not impaired. , Fillers, antifouling agents and the like can be included.
The base film in the laminate material may be an unstretched film, a uniaxially stretched film, or a biaxially stretched film. The thickness is not particularly limited, but is usually about 1 to 200 μm, preferably 3 to 150 μm, more preferably 5 to 100 μm, from the viewpoints of laser light transmittance and lamination workability.
The laminate material needs to have a transmittance of 80% or more for the laser beam irradiated during recording and erasing. By setting the laser beam transmittance to 80% or more, rewriting can be performed without reducing the recording speed, and the amount of heat necessary for coloring and erasing of the thermosensitive coloring layer located thereunder can be imparted. A preferable laser beam transmittance is 85% or more.
The visible light transmittance of the laminate material is preferably 80% or more. When the visible light transmittance is 80% or more, the visibility of the visible information recorded on the thermosensitive coloring layer of the recording medium and the barcode readability are good. A more preferable visible light transmittance is 85% or more.
In the present invention, the laser beam and visible light transmittance of the laminate material are values measured according to JIS K0115.
The laser beam transmittance and the visible light transmittance of the laminate material described above are based on a base material including the laminate material when a substrate film provided with an adhesive layer and an ink receiving layer, which will be described later, is used. The laser beam transmittance and visible light transmittance of the material film are meant.
In the laminate material, when the base film has ultraviolet absorptivity, when the recorded medium is left after recording, the image density is lowered by ultraviolet rays including sunlight, and the dye is a dye precursor. And the decomposition of the light-absorbing heat conversion agent can be suppressed, which can greatly contribute to improving the light resistance of the recording medium.
In the laminate material, if necessary, an ink receiving layer can be provided on at least one surface of the base film.
There is no particular limitation on the coating agent constituting the ink receiving layer, and it can be appropriately selected according to the printing method to be used. As the coating agent, a polymer material having a glass transition temperature Tg of about 20 to 100 ° C. is preferable in terms of ink adhesion, and a Tg of 30 to 70 ° C. is preferable.
As the coating agent made of such a polymer material, for example, at least one resin selected from polyester resins, acrylic resins, polyurethane resins, and the like is preferable. Particularly, the polyester resin has durability against laser light. It is preferable because it is excellent in (heat-resistant fracture resistance).
In the present invention, the coating agent can be used to provide an ink receiving layer on one side or both sides of the base film. This ink receiving layer can be provided in accordance with the interface between the formed printing layer and the substrate film.
The method for forming the ink receiving layer is not particularly limited, and a conventionally known method, for example, a solvent-type or solvent-free coating liquid containing the polymer material, using a gravure, a Meyer bar, an air knife, a die coater, or the like. The ink receiving layer can be formed by coating and drying on a substrate film. The thickness of the ink receiving layer is usually about 0.01 to 5 μm, preferably 0.03 to 3 μm, more preferably 0.05 to 2 μm.
A printing layer can be provided on the ink receiving layer formed in this way. There is no particular limitation on the printing method, and a conventionally known method can be used. From the viewpoint of ink durability, it is preferable to use UV curable ink, for example, letterpress (letter printing), gravure, flexo, screen, ink jet. An electrophotographic method can be used.
In order to laminate the laminate material on the recording medium body, it is preferable to laminate the base material film of the laminate material using an adhesive. As the adhesive, various materials such as a heat-sensitive adhesive and a pressure-sensitive adhesive (adhesive) can be used, and those that do not interfere with the color developing function of the lower heat-sensitive color developing layer or the transmission of laser light are preferable.
As the heat-sensitive adhesive, for example, polyethylene, ethylene-vinyl acetate copolymer, polyurethane, polyester, polyvinyl alcohol, and the like can be used. From the viewpoint of laser light transmission and durability, polyester and Polyurethane systems are preferred. There is no restriction | limiting in particular in a coating system, Arbitrary systems can be employ | adopted suitably from well-known coating systems. The thickness of the heat-sensitive adhesive layer is usually about 0.1 to 100 μm, preferably 1 to 50 μm.
On the other hand, examples of pressure-sensitive adhesives (adhesives) include acrylic adhesives typified by acrylic ester copolymers, polyester adhesives, polyurethane adhesives, silicone adhesives, rubber adhesives, and the like. Among them, acrylic pressure-sensitive adhesives and polyester pressure-sensitive adhesives are particularly preferable in terms of laser beam transmission. There is no restriction | limiting in particular in a coating system, Arbitrary systems can be employ | adopted suitably from well-known coating systems. The thickness of this adhesive layer is usually about 3 to 100 μm, preferably 5 to 50 μm.
In these adhesives, various additives such as heat stabilizers, antioxidants, weathering agents, ultraviolet absorbers, mold release agents, lubricants, antistatic agents, as desired, as long as the object of the present invention is not impaired. Fillers, antifouling agents, and the like can be included.
The adhesive layer thus obtained is preferably one that can be crosslinked in order to improve durability from external factors. When forming the adhesive layer, the crosslinking may be promoted by heat treatment or ionizing radiation irradiation, or the adhesion to the base film or each interface layer may be improved.
In addition, when laminating the laminate material after applying the ink receiving layer to the base film of the laminate material, when providing the print layer in the lower layer, the print layer can be provided before the lamination. On the other hand, when the printing layer is provided on the front surface of the base film of the laminate material, it may be either before or after lamination.
Next, the rewritable thermal label of the present invention has an adhesive layer on the surface of the support opposite to the side on which the laminate material in the recording medium is laminated.
The adhesive layer is preferably made of a pressure-sensitive adhesive from the viewpoint of convenience for attaching to the adherend.
The pressure-sensitive adhesive constituting the adhesive layer preferably has a resin composition that exhibits good adhesion to an adherend and does not inhibit this recycling when the adherend and the label are both recycled. A pressure-sensitive adhesive containing an acrylic ester copolymer as a resin component is excellent in recyclability and is suitable. In addition, rubber-based, polyester-based, polyurethane-based adhesives, and the like can also be used. Silicone-based adhesives with excellent heat resistance can also be used, but because the compatibility with the adherend is poor in the recycling process, the recycled resin tends to be non-uniform, causing strength reduction and poor appearance. May be. In addition, this pressure-sensitive adhesive may be any of emulsion type, solvent type, and solventless type, and if it is a cross-linked type, it has excellent water resistance in the washing process for repeated use of the adherend and holds the label. This is preferable for improving the durability. The thickness of the adhesive layer is usually in the range of 5 to 100 μm, preferably 10 to 50 μm.
In the rewritable thermal label of the present invention, a release sheet can be provided on the adhesive layer as necessary. As this release sheet, if necessary, a release agent is applied to a release film substrate such as polyethylene terephthalate (PET), foamed PET, polypropylene, etc., polyethylene laminate paper, glassine paper, clay coat paper, etc. Is used. The release agent is preferably a silicone-based one, and other fluorine-based or long-chain alkyl group-containing carbamate-based ones can also be used. The coating thickness of the release agent is usually in the range of 0.1 to 5.0 μm, preferably 0.2 to 3.0 μm. Moreover, although there is no restriction | limiting in particular about the thickness of a peeling sheet, Usually, it is about 10-150 micrometers.
The formation order of each layer in the rewritable thermal label of the present invention is not particularly limited. For example, on one side of the support, an anchor coat layer, a heat-sensitive color developing layer, if necessary, a light absorption heat conversion layer, and a laminate are provided. After providing the material layers in this order, it is preferable to provide an adhesive layer on the opposite surface of the support. The anchor coat layer, thermosensitive coloring layer, and light absorption heat conversion layer can be applied to the respective coating liquids such as direct gravure, gravure reverse, micro gravure, Meyer bar, air knife, blade, die, roll knife, reverse, curtain coat, etc. The film can be formed by coating, drying, and further heating if necessary, using a coating method such as this, or a printing method such as flexo, letter press, or screen. In particular, the thermosensitive coloring layer is desirably dried at a low temperature so as not to develop color. In the case of an ionizing radiation curable type, it is cured by irradiation with ionizing radiation.
On the other hand, the adhesive layer may be formed by directly applying and drying the adhesive on the support surface by a known method such as a roll knife coater, reverse coater, die coater, gravure coater, Meyer bar, or the like. The adhesive layer may be applied to the release treatment surface of the release sheet and dried to provide an adhesive layer, which is then attached to a support, and the adhesive layer may be transferred. The latter transfer method is preferable because the drying efficiency of the adhesive can be increased without causing color development of the thermosensitive coloring layer provided on the support.
FIG. 1 is an image diagram of an example of a rewrite thermal label of the present invention.
The rewritable thermal label 15 is provided with a heat-sensitive color developing layer 2 and a light-absorbing heat conversion layer 3 in this order on one side of the support 1, and further on the surface thereof a laminate base material having an ink receiving layer 7 thereon. The film 6 is laminated through the adhesive layer 9 and the adhesive layer 4 and the release sheet 5 are sequentially provided on the other surface of the support 1. FIG. In FIG. 1, the printing layer 8 is formed in a necessary portion on the ink receiving layer 7 provided on the laminating base film 6, but the ink receiving layer provided on the lower surface side of the laminating base film 6. You may form in the required part on (not shown) and may form in the required part on the light absorption heat conversion layer 3. FIG. Further, when the light absorption heat conversion layer 3 is not laminated, it may be formed in a necessary portion on the heat-sensitive color forming layer 2.
Next, the non-contact type IC tag with a rewritable thermal label of the present invention (hereinafter sometimes referred to as an RWT-IC tag) includes the rewritable thermal label having a non-contact type invisible information on the adhesive layer surface. It has a structure in which it is attached so as to face an IC tag that can be read and written.
The RWT-IC tag of the present invention includes invisible information recording / erasing means and visible information recording / erasing means that can be written and erased in a non-contact manner, has flexibility, and can be miniaturized. The visible information by the rewrite thermal label depends on the size of the support, but the amount of information that can be recorded is about several tens of characters, whereas the IC tag can record invisible information of about several thousand characters. . Therefore, the RWT-IC tag of the present invention records a minimum amount of information as visible information, and records other detailed information as invisible information, so that a small amount of information can be retained. Furthermore, since it has flexibility, it is excellent also in the sticking property to a curved surface.
FIG. FIG. 2 is an image diagram of an example of the RWT-IC tag of the present invention.
The RWT-IC tag 20 is connected to the FIG. The non-contact type IC tag in which the release sheet 5 attached to the adhesive layer 4 of the rewritable thermal label 15 is peeled off and the adhesive layer 4 is provided with the adhesive layer 11 with the release sheet 12 on the back surface side. 10 has an attached structure. The adhesive layer 11 is for attaching the RWT-IC tag 20 to an adherend, and is preferably made of an adhesive from the viewpoint of convenience.
FIG. 1 and the rewrite thermal label 15 shown in FIG. The RWT-IC tag 20 indicated by 2 peels off the release sheet 5 and the release sheet 12 attached to the adhesive layer 4 and the adhesive layer 11, respectively, and is attached to an adherend 13 that is an article to be managed. Can be transported.
In the present invention, it is preferable to use a near-infrared laser beam having a wavelength in the range of 700 to 1400 nm as the laser beam (laser beam). Those having a wavelength shorter than 700 nm are not preferable because the visibility and the readability of the optical reflection reading symbol are lowered. When the wavelength is longer than 1400 nm, the energy per pulse unit is high and the influence of heat is large, so that the light-absorbing heat conversion layer is gradually destroyed, and the durability of repeated recording and erasure may be reduced.
In the recording method of the present invention, the scanning mirror is continuously driven without oscillating the laser beam, and the locus of the laser beam (virtual laser beam) assumed when the laser beam is oscillated is substantially constant. It is preferable to use a recording method in which a laser beam is oscillated and scanned with a laser beam only when it is moving.
Further, the distance between the surface of the recording medium and the laser light source when performing recording varies depending on the scanning speed and irradiation output, but it is necessary to select the distance in consideration of character density (barcode readability) and character size. Preferably, when recording, the laser output is about 2.0 to 20 W, the irradiation distance is about 150 to 250 mm, and the duty is 100%. When erasing, the laser output is about 5 to 30 W, the irradiation distance is about 200 to 500 mm, and the duty is about 100%. It is. The scan speed is preferably increased within a range that does not impair printing performance or erasing performance.
By irradiating only the energy required for recording with the recording laser beam in a short time, a rapid cooling effect is brought about and a good image can be obtained. Moreover, you may bring about the rapid cooling effect by ventilation of cold wind. For this cooling, scanning with laser light and rapid cooling with cooling air may be performed alternately.
Of the medium on which information is recorded in this way, the rewritable thermal label having an adhesive layer on the back side is affixed to the adherend manually by a machine or a person. When the machine is attached, a grid crimping method, a roller plunger method for crimping with a roll, an air blowing method with air, or the like can be employed. Further, the recording medium can be provided on the adherend not only by using an adhesive but also by any method. In this way, the adherend with the recording medium is cleaned as necessary for reuse, after fulfilling the purpose of transporting the article. As a cleaning method, a method of removing dust by blowing air, a method of washing with water, a method of cleaning with alkaline hot water, and the like are used.
In order to use the used adherend again, it is necessary to rewrite the information on the attached recording medium into new information. For this purpose, first, the recorded image is erased.
Examples of the method for erasing a recorded image in the present invention include heating with laser light and heating with hot air, and the heating means is not particularly limited. Next, an example of the erasing method will be described.
Erasing is performed to rewrite information on the recording medium to new information. In this case, first, near-infrared laser light of 700 to 1400 nm is irradiated on the recorded medium surface. In addition to the laser beam irradiation with a predetermined energy amount, the image remaining rate can be further reduced by further reducing the cooling rate by a method of contacting a hot roll or the like or a method of blowing hot air.
The heating roll can be heated to about 100 to 140 ° C., and any known heating roll can be used without particular limitation as long as it does not damage the surface of the recording medium. For example, a rubber roll, a stainless steel roll, etc. can be used. In particular, a silicone rubber roll having excellent heat resistance can be suitably used. The rubber hardness is preferably 40 degrees or more.
Further, the recorded image can be erased by blowing hot air. In this case, hot air of about 80 to 400 ° C. is blown for about 0.01 to 30 seconds. In consideration of the thermal deformation and erasing speed of the recording medium and the adherend, it is preferable to heat by heating hot air of 100 to 350 ° C. for an extremely short time of about 0.01 to 3 seconds.
Next, after erasing information in this way, new information is recorded by the non-contact method described above. Thus, the adherend and the rewritable thermal label can be used repeatedly by repeating the above steps.
In the present invention, the number of repetitions of recording and erasing can be 1000 times or more. The adherend and the recording medium that have been used a predetermined number of times can be sent together to the recycling process as necessary. When an IC chip or a circuit is provided, it is desirable to remove the recording medium before recycling.
The present invention also uses the above-described RWT-IC tag, and in a non-contact state with respect to both invisible information of each IC tag and visible information recorded by a laser beam on the surface by a reader / writer in the middle of conveyance. The present invention also provides a recording / rewriting method in which erasing or writing of information is automatically repeated a plurality of times.
In this recording / rewriting method, as a reader / writer, it is possible to erase and write information in a non-contact manner by the same device to both the invisible information recording / erasing means and the visible information recording / erasing means in the IC tag. A certain reader / writer can be used.
In the present invention, an article management for automatically erasing or writing information in a non-contact manner by attaching the above-described non-contact type rewritable recording medium, rewritable thermal label or RWT-IC tag of the present invention to the management object A system can be constructed.
This article management system will be described by taking an article management system using the RWT-IC tag of the present invention as an example.
FIG. 3 is an image diagram of an example of an article management system using the RWT-IC tag of the present invention.
A state in which the management object 22 having the RWT-IC tag 20 attached to the upper surface is placed on the conveyor 21 and conveyed in the direction of the arrow is shown. When the management object 22 is transported under the reader / writer 24 for the RWT-IC tag, the conveyor 21 is temporarily stopped and is contacted by the reader / writer 24 for the RWT-IC tag. -Information is erased or written to both the invisible information recording / erasing means and the visible information recording / erasing means of the IC tag 20. Thereafter, the conveyor 21 is restarted, and the management object 22 is conveyed to a predetermined place. The RWT-IC tag reader / writer 24 has both an invisible information erasing and writing function of the RWT-IC tag 20 and a visible information erasing and writing function.
The article management system using the RWT-IC tag of the present invention has various management such as (a) parts management and process management at the production site, (b) management at the distribution stage (inspection, inventory, etc.), (c ) Management at the sales stage (cash register settlement, batch settlement of multiple products, etc.), (d) management at the disposal / recycling stage, (e) logistics management, (f) settlement / rental management (automatic settlement at the cafeteria, (G) Management of books at libraries, (g) Provision of product / product information (provision of traceability information, provision of work information, digitization of posters, etc.), (h) Safety management / crime prevention (expiration date management, anti-theft) (I) prevention of shoplifting), (i) authenticity determination / brand identification, (j) medical accident prevention, (k) animal management, etc., among these, it is preferable to apply to logistics management.
The article management system using the RWT-IC tag of the present invention is effective in the physical distribution management, particularly when the management target is a plastic container containing articles conveyed by a conveyor.
The non-contact type rewritable recording medium of the present invention has the following effects.
(1) By laminating a laminate material on the reversible thermosensitive coloring layer, damage to the recording surface of the recording medium caused by thermal destruction even if recording and erasing of visible information is repeated by laser light irradiation in a non-contact state. And can be reused 1000 times or more. With an increase in the number of times the recording medium is reused, waste can be reduced and the cost for each use can be reduced.
(2) Even when a laminate material is laminated, by selecting the type of the laminate material, it is possible to suppress deterioration in recordability and erasability by laser light, visibility of thermosensitive color recording, and barcode readability by a barcode reader. can do.
(3) Up to now, printing on the thermosensitive coloring layer has been difficult in terms of ink adhesion, but the lamination of the laminate material improves the adhesion of the printing ink, providing visibility that is extremely important for management. The resulting color can be printed, and the delivery work is much easier.
(4) Image storability can be improved in terms of solvent resistance and light resistance by laminating laminate materials.
(5) An RWT-IC tag can be provided by bonding to an IC tag via an adhesive layer. By using this RWT-IC tag for article management, information can be erased or written to both the invisible information recording / erasing means and the visible information recording / erasing means of the RWT-IC tag. The RWT-IC tag is preferably used for construction of an article management system.

実施例５
不可視情報記録・消去手段であるＩＣチップと、それに接続されているアンテナ回路から構成されている非接触ＩＣタグ［リンテック社製、商品名「ＴＳ−Ｌ１０２ＣＣ」］の表面に、実施例１で得られたリライトサーマルラベルを、剥離シートを剥がして貼付し、Ｆｉｇ．２に示すＲＷＴ−ＩＣタグ２０を作製した。
次に、このＲＷＴ−ＩＣタグ２０を、剥離シート１２を剥がして内容物を入れた管理対象物であるプラスチックコンテナ（サイズ：長さ５５０ｍｍ、幅５００ｍｍ、高さ１００ｍｍ）の上面に貼付し、この管理対象物をコンベア上に載置し、下記のＲＷＴ−ＩＣタグ用リーダ／ライタを用いて、以下に示す試験を行った。
ＲＷＴ−ＩＣタグ用リーダ／ライタとして、後述する可視情報の記録・消去用レーザヘッド３４としてのＹＡＧ（ＦＡＹｂ）レーザマーカー［サンクス社製、機種名「ＬＰ−Ｖ１０」、発振波長１０６４ｎｍ］と、後述する不可視情報の記録・消去用部材３５［ウエルキャット社製、Ｒ／Ｗコントローラ「ＴＥ−３０１−ＲＳ」＋アンテナ「ＡＮ−１０２」］とを搭載した装置を用いた。
可視情報の記録・消去用レーザヘッド３４による記録・消去可能な距離は、プラスチックコンテナの上面から記録の場合１８０ｍｍ、消去の場合２３０ｍｍの高さに自動的になるように設定した。
不可視情報の記録・消去用部材３５の記録・消去可能な距離は、プラスチックコンテナの上面から１５０ｍｍの高さに設定した
Ｆｉｇ．４（ａ）、Ｆｉｇ．４（ｂ）及びＦｉｇ．４（ｃ）は、本実施例における試験方法を示す説明図である。
まず、コンベア２１上に、上面にＲＷＴ−ＩＣタグ２０が貼付された管理対象物２２を載置する［Ｆｉｇ．４（ａ）］。次いで、コンベア２１を稼動して、前記管理対象物２２を、ＲＷＴ−ＩＣタグ用リーダ／ライタ２４内に搬送し、コンベア２１の稼動を停止する［Ｆｉｇ．４（ｂ）］。
ＲＷＴ−ＩＣタグ用リーダ／ライタ２４には、可視情報の記録・消去用レーザヘッド３４と、不可視情報の記録・消去用部材３５とが搭載されている。また下部には、管理対象物２２が出入りするためのゴム系のすだれ状カーテン３７が設けられ、さらに正面側には、レーザ遮断樹脂フィルムを張ったのぞき窓が設けられている（図示せず）。
試験は、可視情報の確認を次のようにして行った。前記管理対象物２２に貼付されたＲＷＴ−ＩＣタグ２０の非接触リライトサーマルラベルに、内容物の品名、サイズを可視情報として可視情報の記録・消去用レーザヘッド３４により、（１）記録、（２）（１）で記録した可視情報の消去、を行った。結果は、（１）記録、（２）消去が確実に行われたことを目視で確認できた。
一方、不可視情報の確認を次のようにして行った。ＲＷＴ−ＩＣタグ２０の非接触ＩＣタグに内容物の品名、サイズ、ロット番号、数量を不可視情報として不可視情報の記録・消去用部材３５により、（１）記録、（２）（１）で記録した不可視情報の消去、を行った。結果はハンディタイプのリーダ［ウエルキャット社製、機種名「ＲＨＴ−１００−０２」］で非接触ＩＣタグの情報を読み取り、（１）記録、（２）消去が確実に行われたことを確認した。
以上より可視情報、不可視情報共に非接触でデータの書き込み及び消去を同一装置により自動的に行うことが可能であることが確認でき、期待どおりの結果が得られた。
試験終了後、コンベア２１を再稼動して、管理対象物２２を、ＲＷＴ−ＩＣタグ用リーダ／ライタ２４の外に搬送した［Ｆｉｇ．４（ｃ）］。 EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples.
The performance evaluation of the rewritable recording medium obtained in each example was performed according to the following method.
<Recording (printing) method>
Recording was performed using a YAG (FAYb) laser (wavelength 1064 nm) [trade name “LP-V10” manufactured by Sunkus Co., Ltd.] as a laser marker for irradiating a laser beam.
Adjust the irradiation distance 180mm, laser output 10W, duty 100%, scan speed 1000mm / sec, pulse period 100μs, line width 0.1mm, fill interval 0.05mm, and record 10 characters from alphabet A to J Went.
<Erase method>
The recording medium was blown with hot air having a tip temperature of 300 ° C. from a distance of 10 mm for 2 seconds, and then erased by natural cooling.
<Rewriting test>
The recording method (1) and the erasing method (2) were repeated 10 times, 300 times and 1000 times.
(1) Evaluation of recorded image For the test samples obtained in each example, the recording density and the surface destruction state at a predetermined number of times of rewriting and the visibility at the time of 10 times of rewriting were evaluated.
(A) Recording Density Using a Macbeth optical densitometer [manufactured by Macbeth Co., Ltd., model name “RD918”], evaluation was performed according to the following criteria.
◎: Optical density 0.75 or more ○: Optical density 0.65 to less than 0.75 Δ: Optical density 0.55 to less than 0.65 ×: Optical density less than 0.55 (b) Surface breakdown state Surface roughness meter [Mitutoyo Corporation, model name “SV300S4”] was used to prepare samples of various surface states before laminating the laminate material, 10-point average surface roughness Rz was measured, and the following criteria were set. The test samples obtained in each example and the samples of the various surface states were visually compared and evaluated according to the criteria.
Standard (no printing) 2.11 μm measured value ◎: Change less than 0.5 μm ○: Change 0.5 to less than 1.0 μm △: Change 1.0 to less than 2.0 μm ×: Change 2.0 μm or more (c) Visual recognition The recording state at the time of rewriting 10 times was visually observed, and the visibility was evaluated according to the following criteria.
The values in parentheses indicate the corresponding optical density values.
A: Characters can be easily visually recognized. (Optical density 1.2 or more)
○: Visible, but the concentration is slightly low. (Optical density 1.0 to less than 1.2)
Δ: Barely visible. (Optical density 0.5 to less than 1.0)
X: Not visible. (Optical density less than 0.5)
(2) Laser beam and visible light transmittance of laminate material The transmittance of the laminate material at a laser wavelength of 1064 nm and a visible light beam of 550 nm was measured with a spectrophotometer [manufactured by Shimadzu Corporation, model name “UV-3100PC”]. did.
(3) Printing ink adhesion Based on JIS K 5600-8-5, the printing ink when the cellophane adhesive tape was applied and peeled off was determined as (excellent) 0, 1, 2, 3, 4, It was quantified in 6 stages of 5 (poor).
(4) Solvent resistance The recorded sample was immersed in ethanol for 1 hour to visually observe the image change and evaluated according to the following criteria. The values in parentheses indicate the corresponding optical density values.
A: Characters can be easily visually recognized. (Optical density 1.2 or more)
○: Visible, but the concentration is slightly low. (Optical density 1.0 to less than 1.2)
Δ: Barely visible. (Optical density 0.5 to less than 1.0)
X: Not visible. (Optical density less than 0.5)
Production Example 1 Preparation of Coating Liquid for Forming Thermosensitive Coloring Layer (Liquid A) As a dye precursor, 3- (4-diethylamino-2-ethoxyphenyl) -3- (1-ethyl-2), which is a triarylmethane compound -Methylindol-3-yl) -4-azaphthalide 10 parts by weight, 30 parts by weight of 4- (N-methyl-N-octadecylsulfonylamino) phenol as reversible developer, vinyl chloride-vinyl acetate co-polymer as binder resin 25 parts by weight of coalescence [manufactured by Union Carbide, trade name “VAGH”], 1.5 parts by weight of polyvinyl acetal as a dispersing agent and 2500 parts by weight of tetrahydrofuran as a diluting solvent are pulverized and dispersed by a pulverizer and a disper, and heat sensitive. A coloring layer forming coating solution (solution A) was prepared.
Production Example 2 Preparation of coating liquid for forming light-absorbing heat conversion layer (liquid B) Near-infrared light-absorbing heat converting agent (nickel complex dye) [trade name “SDA-5131” manufactured by Tosco Co., Ltd.] 1 part by mass, UV curable binder (urethane acrylate) [manufactured by Dainichi Seika Kogyo Co., Ltd., trade name “PU-5 (NS)”] and 100 parts by mass of inorganic pigment (silica) [manufactured by Nippon Aerosil Kogyo Co., Ltd. , Trade name "Aerosil R-972"] 3 parts by mass was dispersed with a disper to prepare a light-absorbing / heat-converting layer-forming coating liquid (B liquid).
Production Example 3 Production of Adhesive Layer with Release Sheet Silicone Resin [Toray Dow] with a catalyst added on a 100 μm thick polyethylene terephthalate (PET) film [trade name “Lumirror T-60” manufactured by Toray Industries, Inc.] A release sheet was produced by applying Corning Co., Ltd. product name “SRX-211”] to a thickness of 0.7 μm after drying. On the silicone resin layer of the release sheet, 100 parts by mass of an acrylic pressure-sensitive adhesive [manufactured by Toyo Ink Manufacturing Co., Ltd., trade name “Olivein BPS-1109”] and a crosslinking agent [trade name “manufactured by Nippon Polyurethane Industry Co., Ltd. The pressure-sensitive adhesive coating solution to which 3 parts by mass of Coronate L ”] was added was applied by a roll knife coater method so that the thickness after drying was 30 μm. This pressure-sensitive adhesive-coated film was dried in an oven at a temperature of 100 ° C. for 2 minutes to produce a pressure-sensitive adhesive layer with a release sheet.
Example 1
As a support, a foamed polyethylene terephthalate film having a thickness of 100 μm [manufactured by Toyobo Co., Ltd., trade name “Crisper 50K2411”] is coated with the liquid A prepared in Production Example 1 on the easy-adhesion coat side by a gravure method. The coating was applied to 4 μm and dried in an oven at 60 ° C. for 5 minutes to form a thermosensitive coloring layer. Next, the liquid B prepared in Production Example 2 was applied on the thermosensitive coloring layer by a flexographic method so that the thickness after drying was 1.2 μm, and dried in an oven at 60 ° C. for 1 minute. The light absorption heat conversion layer was produced by irradiating with ultraviolet rays at a light amount of 220 mJ / cm ² .
Next, the surface on which the thermosensitive coloring layer and the light absorption heat conversion layer were not formed and the pressure-sensitive adhesive layer with a release sheet prepared in Production Example 3 were bonded together with a laminator to obtain a recording sample.
On the other hand, a 25 μm thick PET film [trade name “Lumirror T type”, glass transition temperature: 70 ° C., melting point: 260 ° C.] on one side (upper layer) as a base film for laminating, polyester Resin [trade name “Byron 20SS” manufactured by Toyobo Co., Ltd.] was applied to a dry thickness of 0.1 μm to form an ink receiving layer. On the opposite surface (lower layer) of this ink receiving layer, as an acrylic cross-linking pressure-sensitive adhesive, 100 parts by weight of an acrylic pressure-sensitive adhesive [trade name “BPS-1109” manufactured by Toyo Ink Manufacturing Co., Ltd.] Polyurethane Co., Ltd., trade name “Coronate L”] An adhesive coating solution containing 3 parts by mass was applied so that the thickness after drying was 20 μm, and dried at 100 ° C. for 1 minute. Layers were formed to produce a laminate material. The laser beam (wavelength 1064 nm) and visible light (wavelength 550 nm) transmittance of this laminate material were measured.
Next, the laminate material thus produced was laminated on the light absorption heat conversion layer of the previous recording sample. Next, a UV curable ink [trade name “Bestcure 161 ink” manufactured by T & KTOKA Co., Ltd.] is used on the ink receiving layer surface of the laminate material, and partially at room temperature using a label printer “LPM300” manufactured by Lintec Corporation. Then, the rewritable thermal label of the present invention was manufactured, and then cut into a 10 cm square sheet sample to prepare a test sample for recording / erasing.
A performance evaluation test was performed on the test sample. The results are shown in Table 1.
Example 2
In Example 1, a transparent vinyl chloride film having a thickness of 80 μm [manufactured by Riken Technos Co., Ltd., trade name “PVC transparent A23P 80 μm”, glass transition temperature: 82 ° C., melting point: 180 ° C.] was used as the base film for laminating. And, except that the ink receiving layer was not provided, the same operation as in Example 1 was performed to prepare a test sample, and a performance evaluation test was performed. The results are shown in Table 1.
Example 3
In Example 1, instead of providing a printing layer on the ink receiving layer surface of the laminate material, the same operation as in Example 1 was performed except that a printing layer was provided at the interface between the light-absorbing heat conversion layer and the adhesive layer of the laminate material. The sample for a test was produced and the performance evaluation test was done. The results are shown in Table 1.
Example 4
In Example 1, except that an ink receiving layer was not provided on the base material film of the laminate material, the same operation as in Example 1 was performed to prepare a test sample, and a performance evaluation test was performed. The results are shown in Table 1.
Comparative Example 1
In Example 1, a test sample was prepared by performing the same operation as in Example 1 except that the laminate material composed of the ink receiving layer, the base film for laminating, and the pressure-sensitive adhesive layer was not laminated. The results of the tests are shown in Table 2.
Comparative Example 2
In Example 1, as a base film for laminating, a polyethylene film having a thickness of 50 μm and a laser beam transmittance of 75% [manufactured by Yodogawa Chemical Co., Ltd., trade name “LDPE 50 μm”, glass transition temperature: −25 ° C., melting point : 130 ° C.], except that the same operation as in Example 1 was performed to prepare a test sample, and a performance evaluation test was performed. The results are shown in Table 2.
Comparative Example 3
In Example 1, as the base film for laminating, the surface of the PET film was subjected to sand matting treatment, and the matted film having a thickness of 25 μm and a laser beam transmittance of 76% [manufactured by Teijin DuPont Films Ltd., trade name “ TS 25 μm ”, glass transition temperature: 70 ° C., melting point: 260 ° C.] were used, and a test sample was prepared by performing the same operation as in Example 1 except that the ink receiving layer was not provided. A test was conducted. The results are shown in Table 2.
Comparative Example 4
In Example 1, as a base film for laminating, a polypropylene film having a thickness of 20 μm and a laser beam transmittance of 78% [manufactured by Sun Tox Co., Ltd., trade name “PA 20 μm”, glass transition temperature: −20 ° C., melting point : 170 ° C.], except that the same operation as in Example 1 was performed to prepare a test sample, and a performance evaluation test was performed. The results are shown in Table 2.

Example 5
Obtained in Example 1 on the surface of a non-contact IC tag [trade name “TS-L102CC”, manufactured by Lintec Corporation] composed of an IC chip which is an invisible information recording / erasing means and an antenna circuit connected thereto. The release sheet was peeled off and affixed to the rewritable thermal label, FIG. The RWT-IC tag 20 shown in 2 was produced.
Next, the RWT-IC tag 20 is affixed to the upper surface of a plastic container (size: length 550 mm, width 500 mm, height 100 mm) which is a management object in which the release sheet 12 is peeled off and the contents are put. The management object was placed on a conveyor, and the following tests were performed using the following RWT-IC tag reader / writer.
As a reader / writer for an RWT-IC tag, a YAG (FAYb) laser marker [manufactured by Sunkus, model name “LP-V10”, oscillation wavelength 1064 nm] as a laser head 34 for recording / erasing visible information, which will be described later, is described later. A device equipped with a member 35 for recording / erasing invisible information [manufactured by Wellcat, R / W controller “TE-301-RS” + antenna “AN-102”] was used.
The distance at which visible information can be recorded / erased by the laser head 34 for recording / erasing was set to be automatically 180 mm from the top surface of the plastic container and 230 mm from the plastic container.
The recordable / erasable distance of the invisible information recording / erasing member 35 is set to a height of 150 mm from the upper surface of the plastic container. 4 (a), FIG. 4 (b) and FIG. 4 (c) is an explanatory view showing a test method in this example.
First, the management object 22 having the RWT-IC tag 20 attached to the upper surface is placed on the conveyor 21 [FIG. 4 (a)]. Next, the conveyor 21 is operated, the management object 22 is conveyed into the reader / writer 24 for the RWT-IC tag, and the operation of the conveyor 21 is stopped [FIG. 4 (b)].
The RWT-IC tag reader / writer 24 is equipped with a visible information recording / erasing laser head 34 and an invisible information recording / erasing member 35. In addition, a rubber-type interdigital curtain 37 through which the management object 22 enters and exits is provided at the lower portion, and a viewing window with a laser blocking resin film is provided on the front side (not shown). .
In the test, the visual information was confirmed as follows. On the non-contact rewritable thermal label of the RWT-IC tag 20 affixed to the management object 22, (1) recording by the visible information recording / erasing laser head 34 with the product name and size of the contents as visible information ( 2) The visible information recorded in (1) was deleted. As a result, (1) recording and (2) erasure could be confirmed visually.
On the other hand, the invisible information was confirmed as follows. The invisible information recording / erasing member 35 records the product name, size, lot number, and quantity of the contents as non-visible information on the non-contact IC tag of the RWT-IC tag 20 (1), (2) and (1). Deleted invisible information. As a result, the information of the non-contact IC tag was read with a handy type reader [manufactured by Welcat, model name “RHT-100-02”], and (1) recording and (2) erasure were confirmed. did.
From the above, it was confirmed that both visible information and invisible information can be automatically written and erased by the same apparatus without contact, and the expected result was obtained.
After the test was completed, the conveyor 21 was restarted, and the management target 22 was conveyed out of the reader / writer 24 for RWT-IC tag [FIG. 4 (c)].

The non-contact type rewritable recording medium of the present invention can remarkably improve the rewriting durability (heat fracture resistance) while maintaining repetitive recording / erasing performance using a laser, and is suitable for printing and solvent resistance. The image storability can be improved in terms of light resistance, and writing and / or erasing of visible information can be automatically performed in a non-contact state using a laser without manual intervention.
In addition, an RWT-IC tag can be provided by bonding to an IC tag through an adhesive layer. By using this RWT-IC tag for article management, information can be erased or written to both the invisible information recording / erasing means and the visible information recording / erasing means of the RWT-IC tag. The RWT-IC tag is preferably used for construction of an article management system.

Claims (12)

A non-contact type rewritable recording medium capable of recording / erasing with a laser beam, wherein a reversible thermosensitive coloring layer is provided on a support surface, and a laminate material is laminated on the reversible thermosensitive coloring layer, A non-contact rewritable recording medium having a laser beam transmittance of 80% or more. The non-contact type rewritable recording medium according to claim 1, wherein the visible light transmittance of the laminate material is 80% or more. The nonabsorbing heat converting layer according to claim 1 or 2, wherein a light absorbing heat converting agent is contained in the reversible thermosensitive coloring layer or a light absorbing heat converting layer having a light absorbing heat converting agent is provided on the reversible thermosensitive coloring layer. A contact-type rewritable recording medium. The laminate material according to any one of claims 1 to 3, wherein an adhesive layer is provided on a base film, the glass transition temperature of the base film is 60 ° C or higher, and the melting point is 150 ° C or higher. The non-contact type rewritable recording medium according to item 1. The laminate material according to any one of claims 1 to 4, wherein the laminate material is a base film provided with an adhesive layer, and the base film is a polyester resin film or a vinyl chloride resin film. A non-contact type rewritable recording medium described in 1. The non-contact type rewritable recording medium according to any one of claims 1 to 5, wherein the wavelength of the laser beam is 700 to 1400 nm. The non-contact type rewritable recording medium according to any one of claims 1 to 6, wherein an ink receiving layer is provided on at least one surface of the base material film of the laminate material. The non-contact type rewritable recording medium according to any one of claims 1 to 7, which has a printing layer on a base material film of a laminate material or on an ink receiving layer surface provided on the base material film. The non-contact type rewritable recording medium according to any one of claims 1 to 6, wherein a printing layer is provided on the surface of the reversible thermosensitive coloring layer or light absorption heat conversion layer. A rewritable thermal label comprising an adhesive layer on the surface of the support opposite to the side on which the laminate material of the non-contact type rewritable recording medium according to any one of claims 1 to 9 is laminated. . A rewrite comprising the non-contact type recordable rewritable adhesive label according to claim 10 bonded so that the surface of the adhesive layer faces a non-contact type invisible information read / write IC tag. Non-contact IC tag with thermal label. Using the non-contact type IC tag with a rewritable thermal label according to claim 11, both invisible information of each IC tag and visible information recorded on the surface by laser light by a reader / writer in the middle of conveyance A recording / rewriting method characterized by automatically erasing or writing information a plurality of times in a non-contact state.

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