JP6943057B2 - Laser color-developing sheet and card - Google Patents

Description

The present invention relates to a laser color-developing sheet used for cards such as magnetic stripe cards and IC cards, and more particularly to a laser color-developing sheet having excellent heat resistance, heat fusion property, and mechanical properties.

Cards such as credit cards, cash cards, ID cards, and tag cards are manufactured in the form of punched cards by stacking multiple card sheets, heating and fusing each sheet with a vacuum press, and then punching them with a punching machine. .. Such a card is irradiated with a laser beam to mark characters, barcodes, and the like. For example, instead of printing a barcode, a face photo, or the like, a YAG laser or the like is used to write the individual number or lot number of the card, personal information, the face photo, or the like on the card. In this way, if the information is written on the card by a laser or the like, it is possible to prevent the personal information from being lost due to wear or deterioration over time. In addition, marking using a laser can be performed in a simple process, so that it has high industrial value and is attracting attention.

On the other hand, the layer containing the laser light energy absorber generally needs to have high heat resistance enough to withstand the irradiation of the laser light. Therefore, when manufacturing a card by heat-sealing a plurality of card sheets, the temperature of the heat-sealing must be set high. Therefore, a technique for lowering the heat fusion temperature is desired.

Here, Patent Document 1 is a card sheet having a color-developing layer that develops color by irradiating a laser beam and an adhesive layer on at least one surface, and is excellent in low-temperature fusion property and handleability. Sheets are listed.

Further, Patent Document 2 describes a laser marking multilayer sheet composed of at least three layers having a skin layer and a core layer, which is formed by coextrusion, and has improved transparency, sheet transportability, and a mold after hot pressing. A laser marking multilayer sheet having a mold release property, heat resistance, bending property, and abrasion resistance is disclosed.

Further, in Patent Document 3, the skin layer is made of an amorphous aromatic polyester resin having a glass transition temperature of 90 ° C. or higher, and the core layer is made of a polycarbonate resin, which is excellent in heat resistance and heat fusion property. Sheets for use are disclosed.

Japanese Unexamined Patent Publication No. 2004-243685 JP-A-2010-194757 Japanese Unexamined Patent Publication No. 2013-1089

However, since the card sheet described in Patent Document 1 contains a substantially amorphous aromatic polyester resin as a main component in its adhesive layer, the mechanical properties required for the card, particularly the bending strength (dynamic bending), are required. Power) was insufficient.

Further, in the laser marking multilayer sheet described in Patent Document 2, since the skin layer contains a polycarbonate resin as a main component, it is excellent in heat resistance, bending property, and abrasion resistance, but it is used in the laminating process at the time of card manufacturing. The heat fusion temperature was high, and improvement was required.

Further, although the card sheet described in Patent Document 3 is excellent in both heat resistance and heat fusion property, the tensile elongation at break, which is one of the mechanical properties, is insufficient, and further improvement has been desired. ..

Further, it has become clear that the sublimation type thermal transfer image receiving layer arbitrarily provided on the outermost surface layer of the card sheet turns yellow when the card is heated and fused at a temperature exceeding a specific temperature during the manufacturing of the card.

Therefore, according to the present invention, in the laser color-developing sheet having laser color-developing property, the mechanical properties are excellent, the temperature of heat fusion during the manufacture of the card can be lowered, and the sublimation type heat transfer image receiving layer arbitrarily provided can be provided. It is an object of the present invention to provide a laser color-developing sheet that does not turn yellow even after heat fusion, and a card using the laser color-developing sheet.

That is, the present invention is a laser color-developing sheet formed from at least two sheets having an adhesive layer (A) and a color-developing layer (B).
A polyester resin in which the adhesive layer (A) contains a diol component having at least one alicyclic structure selected from spiroglycol, isosorbide, and 2,2,4,4-tetramethyl-1,3-cyclobutanediol. It contains (a1) and an impact improver (a2), and the mass ratio of the polyester resin (a1) and the impact improver (a2) is (a1) / (a2) = 60/40 to 90/10. ,
We propose a laser color-developing sheet characterized in that the color-developing layer (B) contains 0.01 to 10 parts by mass of a laser light energy absorber with respect to 100 parts by mass of a polycarbonate resin.

According to the present invention, it is assumed that a laser color-developing sheet having excellent laser color-developing property and further having mechanical properties and heat-sealing property at a low temperature can be obtained, and a sublimation type thermal transfer image receiving layer is optionally provided. It is also possible to provide a card in which yellowing does not occur after heat fusion.

It is a figure which shows an example of the laser color-developing sheet of this invention. It is a figure which shows an example of the card of this invention. It is a figure which shows an example of the card of this invention.

The laser color-developing sheet of the present invention is a laser color-developing sheet formed of at least two sheets having an adhesive layer (A) and a color-developing layer (B).
A polyester resin in which the adhesive layer (A) contains a diol component having at least one alicyclic structure selected from spiroglycol, isosorbide, and 2,2,4,4-tetramethyl-1,3-cyclobutanediol. It contains (a1) and an impact improver (a2), and the content ratio of the polyester resin (a1) and the impact improver (a2) is (a1) :( a2) = 60: 40 to 90:10 mass%. And
The color-developing layer (B) is characterized by containing 0.01 to 10 parts by mass of a laser light energy absorber with respect to 100 parts by mass of a polycarbonate resin.

First, the layer structure of each sheet used in the present invention will be specifically described.

<Adhesive layer (A)>
The adhesive layer (A) used in the present invention is a layer that can be adhered to another card sheet by heat fusion, and has a role of imparting excellent mechanical strength and low temperature fusion property to the laser color-developing sheet of the present invention. To bear. Further, the adhesive layer (A) is a polyester resin (a1) containing a diol component having at least one alicyclic structure from the viewpoint of imparting low temperature fusion property and improving bending strength and tensile elongation at break. ) And the impact improver (a2).

(Polyester resin (a1))
Since the polyester resin (a1) has a lower Tg than the polycarbonate resin which is the main component of the coloring layer (b) described later, the heat fusion temperature with the core sheet and the oversheet is lowered when manufacturing the card. be able to. That is, low temperature fusion property can be imparted. It also has excellent transparency and excellent flexibility, which is also preferable in terms of improving bending strength.

The diol component having an alicyclic structure contained in the polyester resin (a1) contains spiroglycol, isosorbide, 2,2,4,4-tetramethyl- from the viewpoint of imparting low temperature fusion property and improving bending strength. It is important that the resin has a diol component having at least one alicyclic structure selected from 1,3-cyclobutanediol. Of these, 2,2,4,4-tetramethyl-1,3-cyclobutanediol is more preferable.

The content of the above-mentioned diol component is preferably 5 to 40 mol%, preferably 10 to 30 mol%, based on the total amount of the diol component, from the viewpoint of imparting low-temperature fusion property to the adhesive layer (A). More preferably, it is 15 to 25 mol%.

Examples of dicarboxylic acid components include terephthalic acid, isophthalic acid, 2-chloroterephthalic acid, 2,5-dichloroterephthalic acid, 2-methylterephthalic acid, 4,4-stylbenzicarboxylic acid, and 4,4-biphenyldicarboxylic acid. Orthophthalic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, bisbenzoic acid, bis (p-carboxyphenyl) methane, anthracenedicarboxylic acid, 4,4-diphenyletherdicarboxylic acid, 4,4-diphenoxy Aromatic dicarboxylic acids such as ethanedicarboxylic acid, 5-Nasulfoisophthalic acid, ethylene-bis-p-benzoic acid, adipic acid, sebacic acid, azelaic acid, dodecanedioic acid, 1,3-cyclohexanedicarboxylic acid, 1,4 − An aliphatic dicarboxylic acid component such as cyclohexanedicarboxylic acid can be mentioned. These dicarboxylic acid components may be used alone or in combination of two or more. In the present invention, terephthalic acid and isophthalic acid are particularly preferable as the dicarboxylic acid because it is industrially inexpensive and the synthesized polyester resin (a1) is chemically stable.

The glass transition temperature of the polyester resin (a1) containing a diol component having an alicyclic structure is preferably 95 ° C. or higher, preferably 100 ° C. or higher, from the viewpoint of imparting heat resistance to the laser color-developing sheet. Is more preferable, and 105 ° C. or higher is even more preferable. On the other hand, from the viewpoint of imparting low temperature fusion property, the temperature is preferably 130 ° C. or lower, more preferably 125 ° C. or lower, and even more preferably 120 ° C. or lower.

As the polyester resin (a1) containing a diol component having an alicyclic structure, various commercially available raw materials can be preferably used. For example, the trade name: "ALTESTER (registered trademark)" (Mitsubishi Gas Chemical Co., Ltd.) (Manufactured by, using spiroglycol), trade name: "TRITAN (registered trademark)" (manufactured by EASTMAN Chemical Co., Ltd., using 2,2,4,4-tetramethyl-1,3-cyclobutanediol), and trade name: "ECOZEN (registered trademark)" (manufactured by SK Chemical Co., Ltd., using isosorbide) and the like can be mentioned.

From the viewpoint of adjusting the glass transition temperature (Tg) and the refractive index, other polyester resins and additives may be used in combination in addition to the above resins.

(Impact improver (a2))
The impact resistance improving agent (a2) used in the present invention is a multilayer structure polymer composed of a core layer and one or more shell layers covering the core layer, and is an aromatic vinyl-based polymer for all the components constituting the shell layer. The unit content is preferably 50% by mass or more.

The multilayer structure polymer is a polymer having a so-called core-shell type structure, which is composed of a core layer and one or more shell layers covering the core layer, and adjacent layers are composed of different kinds of polymers. The above-mentioned aromatic vinyl-based unit may be contained in any layer of the multilayer polymer. The number of layers constituting the multilayer structure polymer is not particularly limited, and may be two or more layers, and may be three or more layers or four or more layers.

The type of the core layer is not particularly limited, and is composed of, for example, a polymer of a (meth) acrylic component, a silicone component, a styrene component, a nitrile component, a conjugated diene component, a urethane component, an ethylene propylene component, or the like. Examples thereof include polymers having rubber elasticity. For example, (meth) acrylic components such as (meth) ethyl acrylate units, (meth) butyl acrylate units, (meth) -2-ethylhexyl acrylate units and benzyl (meth) acrylate units, dimethyl siloxane units and phenylmethyl. It is composed of polymerized silicone components such as siloxane units, styrene components such as styrene units and α-methylstyrene units, nitrile components such as acrylonitrile units and methacrylonitrile units, or conjugated diene components such as butanediene units and isoprene units. Examples thereof include rubber, which can be used alone or in combination of two or more.

The type of the shell layer is not particularly limited, and is an unsaturated carboxylic acid alkyl ester-based unit, a glycidyl group-containing vinyl-based unit, an aliphatic vinyl-based unit, an aromatic vinyl-based unit, a vinyl cyanide-based unit, and a maleimide-based unit. Examples thereof include polymers containing units, unsaturated dicarboxylic acid-based units, unsaturated dicarboxylic acid anhydride-based units and / or other vinyl-based units, and these may be used alone or in combination of two or more.

The impact resistance improving agent (a2) used in the present invention preferably contains 50% by mass or more of aromatic vinyl-based units with respect to all the components constituting the shell layer. When the content of the aromatic vinyl-based unit is 50% by mass or more, impact improvement can be imparted while maintaining the transparency of the laser color-developing sheet. From this point of view, it is more preferable to contain 60% by mass or more of the aromatic vinyl-based unit, and further preferably 70% by mass or more.

As aromatic vinyl-based units, styrene, α-methylstyrene, 1-vinylnaphthalene, 4-methylstyrene, 4-propylstyrene, 4-cyclohexylstyrene, 4-dodecylstyrene, 2-ethyl-4-benzylstyrene, 4 -(Phenylbutyl) styrene, halogenated styrene and the like can be mentioned, and among them, styrene or α-methylstyrene is more preferable.

As the multilayer structure polymer used in the present invention, a commercially available product may be used as long as it satisfies the above-mentioned conditions, or it can be produced by a known method.

Commercially available products include, for example, Mitsubishi Chemical's "Metabrene (registered trademark)", Kaneka's "Kaneace (registered trademark)", Roam & Haas's "Pararoid (registered trademark)", and Aica Kogyo's "Staphyroid (registered trademark)". Or "Paraface (registered trademark)" manufactured by Kuraray, etc., which may be used alone or in combination of two or more.

The mass ratio of the polyester resin (a1) to the impact improver (a2) is preferably (a1) / (a2) = 60/40 to 90/10 mass%. When the content of the impact improving agent (a2) is 10% by mass or more, excellent mechanical properties can be imparted to the laser color-developing sheet of the present invention. From this point of view, it is more preferably 15% by mass or more, and further preferably 20% by mass or more. On the other hand, from the viewpoint of transparency, the upper limit is preferably 40% by mass or less, more preferably 35% by mass or less, and further preferably 30% by mass or less.

From the viewpoint of heat resistance, the glass transition temperature (Tg) of the adhesive layer (A) is preferably 95 ° C. or higher, more preferably 100 ° C. or higher, and even more preferably 105 ° C. or higher. On the other hand, from the viewpoint of imparting low temperature fusion property, the temperature is preferably 130 ° C., more preferably 125 ° C. or lower, and even more preferably 120 ° C. or lower.

<Coloring layer (B)>
The color-developing layer (B) used in the present invention is preferably formed mainly of a polycarbonate resin. By using the polycarbonate resin as the main component, the heat resistance of the card can be improved, and even if the laser beam is irradiated, the color-developing layer can be prevented from swelling or deforming.

In the present invention, the polycarbonate-based resin means a resin composition in which the main component is polycarbonate. As the polycarbonate resin, those produced from bisphenol A synthesized from bisphenol and acetone by an interfacial polymerization method, an ester exchange method, a pyridine method, etc., bisphenol A and a dicarboxylic acid derivative, for example, tere (iso) phthalic acid dichloride, etc. Examples thereof include polyester carbonate obtained by the copolymer with and a derivative of bisphenol A, for example, those obtained by polymerization of tetramethylbisphenol A and the like.

The weight average molecular weight of the polycarbonate resin is usually 10,000 to 100,000, preferably 20,000 to 80,000, and particularly preferably 22,000 to 60,000. .. Only one type of polycarbonate resin can be used alone, or two or more types can be used in combination. Here, when the weight average molecular weight is within the above range, impact resistance is ensured and extrusion moldability is also good, which is preferable.

Commercially available products can be used as the polycarbonate resin, and specific examples of the aromatic polycarbonate resin include the trade names "CALIBER (registered trademark)" and "SD Polyca (registered trademark)" manufactured by Sumika Stylon Polycarbonate Co., Ltd. SDPOLYCA (registered trademark) ”, product name manufactured by Mitsubishi Engineering Plastics Co., Ltd.“ Iupilon (registered trademark) ”,“ NOVAREX (registered trademark) ”, product name manufactured by Teijin Co., Ltd. Examples include "Panlite (registered trademark)".

Further, the above-mentioned various additives and other resins can be appropriately blended as long as the effects of the present invention are not impaired. Here, examples of the additive include antioxidants, ultraviolet absorbers, light stabilizers, lubricants, flame retardants, colorants, hydrolysis inhibitors and the like.

As the laser light energy absorber contained in the color-developing layer (B), a metal oxide or the like that absorbs a laser beam and becomes colored by heat generation due to photothermal conversion is preferably used. Specifically, as metals that form black oxides showing good contrast, copper, iron, nickel, manganese, titanium, lead, chromium, cobalt, tin, tarium, vanadium, niobium, molybdenum, ruthenium, rhodium. , Tantal, tungsten, rhenium, osmium, iridium, bismuth, palladium, silver, platinum, gold and the like. Among them, it is preferable to contain oxides of bismuth and neodymium as metal oxides from the viewpoint of having excellent color development even in a small amount.

As another laser light energy absorber, carbon black or a light absorber that absorbs the wavelength of the laser beam may be contained. When such a color-developing layer is irradiated with a laser beam, the surrounding binder resin such as a light absorber is carbonized, and the carbonized portion exhibits black color. Alternatively, a color former such as a metal oxide and a light absorber may be used in combination. Examples of the light absorber preferably used in the present invention include cyanine-based dyes, polymethine-based dyes, anthraquinone-based dyes, phthalocyanine-based dyes, naphthalocyanine-based dyes, etc., which have an absorption peak in the wavelength range of the laser used.

The content of the additive in the laser light energy absorber is preferably in the range of 0.01 to 10 parts by mass with respect to 100 parts by mass of the resin composition forming the color-developing layer (B).

Further, when a bismuth / neodymium-based oxide is used as the laser light energy absorber, the amount of addition can be further reduced. In this case, the amount added is preferably 0.01 to 1.5 parts by mass, preferably 0.01 to 1.3 parts by mass, with respect to 100 parts by mass of the resin composition forming the color-developing layer (B). Is more preferable, and 0.1 to 1.0 parts by mass is further preferable.

<Manufacturing method of laser color-developing sheet>
The method for forming the laser color-developing sheet of the present invention will be described below.
The laser color-developing sheet is formed by, for example, a co-extrusion method in which the materials constituting each layer are supplied to an extruder and co-extruded and laminated, or a method in which each layer is formed in a sheet shape in advance and then laminated. However, in consideration of productivity, cost, etc., it is preferable to form by the coextrusion method. Specifically, first, materials such as a resin composition forming each layer are blended, and if necessary, pellets are formed. Each of these materials is put into each hopper of a T-die extruder in which a plurality of T-dies are connected, melted and extruded together in a temperature range of 200 ° C. to 280 ° C., and cast rolls, mat forming rolls, etc. A laser color-developing sheet is obtained by passing through the space and quenching and solidifying.

When the single-layer sheet for laminating is formed by the laminating method, the material for forming the single-layer sheet is blended, pelletized as necessary, and then pelletized using a T-die extruder. A single-layer sheet can be obtained by melt-extruding in a temperature range of 200 to 280 ° C., passing between cast rolls, and quenching and solidifying. In this case, after the laminate is formed, a matte processing process can be performed. Alternatively, a card sheet as an oversheet or a card sheet as a core sheet may be formed by attaching the obtained single-layer sheet to the base material for an oversheet or the base material for a core sheet. .. The base material for oversheet, the base material for core sheet and the like can be formed by the same method as the laser color-developing sheet of the present invention, but the present invention is not limited to these, and known methods such as JP-A-10 It can be obtained according to the description on pages (6) to (7) of JP-71763.

The total thickness of the laser color-developing sheet of the present invention is preferably in the range of 25 μm to 200 μm, more preferably in the range of 50 μm to 150 μm. Here, the ratio of the thickness of the adhesive layer (A) to the thickness of the color-developing layer (B) is the adhesive layer (A) / color-developing layer in the case of a two-layer structure of the adhesive layer (A) / color-developing layer (B). (B) = 10/90 to 60/40, more preferably 20/80 to 50/50. In the case of a three-layer structure of the adhesive layer (A) / color-developing layer (B) / adhesive layer (A), it is preferably 5/90/5/30/40/30, and more preferably 10/80 /. It is 10 to 25/50/25. If the thickness of the adhesive layer (A) becomes too thin, the adhesiveness with the core sheet, oversheet, and the like deteriorates. On the other hand, if the thickness of the adhesive layer (A) becomes too thick, it may be necessary to make the thickness of the coloring layer (B) relatively thin. If the thickness of the color-developing layer (B) becomes too thin, the color-developing property is lowered, and the legibility of the image obtained by irradiating the laser beam is lowered. Furthermore, the heat resistance of the laser color-developing sheet is also reduced.

Here, FIG. 1 illustrates the configuration of one embodiment of the laser color-developing sheet of the present invention, and laser color-developing a three-layer structure of an adhesive layer (1) / a color-developing layer (2) / an adhesive layer (1). The sex sheet (10) is illustrated.

(Sublimation type thermal transfer image receiving layer (C))
The laser color-developing sheet of the present invention may further have a sublimation type thermal transfer image receiving layer (C) on at least one surface of the adhesive layer (A) or the color-developing layer (B).
The sublimation type thermal transfer image receiving layer (C) is used as the image receiving layer when clearly printing a face photograph or the like of a card in full color. By applying an image receiving layer in order to enhance the affinity between the printing ink and the sheet surface, printing becomes possible more clearly.

As the sublimation type thermal transfer image receiving layer (C), conventionally known ones can be used. For example, a varnish containing a resin that easily transfers or dyes a coloring material as a main component is added with various additives such as a mold release agent, if necessary.

The easily dyeable resin used for the sublimation type thermal transfer image receiving layer (C) is a polyolefine resin such as polypropylene, a halogenated resin such as polyvinyl chloride or polyvinylidene chloride, or a vinyl resin such as polyvinyl acetate or polyacrylic acid ester. And its polymers, polyester resins such as polyethylene terephthalate and polybutylene terephthalate, polystyrene resins, boliamide resins, copolymers of olephine such as ethylene and propylene with other vinyl monomers, ionomers, cellulose derivatives and the like. , Or a mixture can be used, and among these, a polyester resin and a vinyl resin are preferable.

A sublimation type thermal transfer image receiving layer can be formed by dissolving and dispersing the above-mentioned resin in a solvent such as an organic solvent or water and applying the resin. The organic solvent is not particularly limited, but MEK, MIBK, toluene, ethyl acetate, cyclohexane, acetone, tetrahydrofuran, a mixed solvent thereof and the like can be used.

Further, as an additive, a stabilizer such as an epoxy compound, an ultraviolet absorber for improving weather resistance, a defoaming agent, a surfactant and the like for improving coating suitability can be appropriately used.

A mold release agent may be added to the sublimation type heat transfer image receiving layer (C) in order to prevent the image receiving layer from being heat-sealed with the heat transfer sheet during image formation. As the release agent, silicone oil, phosphoric acid ester-based plasticizer, and fluorine-based compound can be used, and among them, silicone oil is preferable. The amount of the release agent added is preferably 2 to 30 parts by mass with respect to 100 parts by mass of the image receiving layer forming resin. Instead of adding and mixing the release agent with the material of the image receiving layer, the release agent layer may be laminated on the surface of the image receiving layer. Further, a fluorescent bleaching agent or other additives may be added to the receiving layer as needed.

Further, an anchor coat layer may be appropriately provided between the sublimation type thermal transfer image receiving layer (C) and the adhesive layer (A). Functions of the anchor coat layer include solvent resistance, barrier performance, adhesive performance, whitening ability, hiding performance, cushioning property, and antistatic property.

Further, the anchor coat layer is a binder made of a thermoplastic resin, and a conductive substance having antistatic properties, for example, needles of conductive acicular crystals (potassium titanate, titanium oxide, aluminum borate, silicon carbide, silicon nitride, etc.). The surface of the shaped crystal treated with a conductive agent) may be dispersed and formed. By imparting antistatic properties, it is possible to prevent transport troubles such as double feed when the thermal transfer printer of the thermal transfer image receiving sheet is supplied.

The sublimation type thermal transfer image receiving layer (C) is usually provided on the surface of the laser color-developing sheet (the surface that becomes the visible side when laminated as a card). The sublimation type thermal transfer image receiving layer (C) is formed by applying a thin film on at least one surface of a laser coloring sheet having an adhesive layer (A) and a coloring layer (B) containing a laser light energy absorber, and undergoing a drying step. Can be formed. As the coating method, a conventionally known method can be adopted.

(Recycled resin)
The laser color-developing sheet in the present invention may contain a recycled resin obtained by reusing the sheet generated in the manufacturing process in the adhesive layer (A) or the color-developing layer (B). By adding the recycled resin to the adhesive layer (A) or the coloring layer (B) and using it in this way, it is possible to reduce costs by reusing resources and reducing waste.

Normally, when a recycled resin is used, problems such as deterioration of transparency occur, but in the laser color-developing sheet of the present invention, the impact improving agent (a2) contained in the adhesive layer (A) is particularly contained in the color-developing layer (B). Since the refractive index is close to that of the polycarbonate resin as the main component, a laser color-developing sheet having good transparency can be obtained even if a recycled resin is added.

For example, when the recycled resin is added to the coloring layer (B), the amount of the recycled resin added is preferably 5% by mass or more, preferably 10% by mass or more, based on the total amount of the resins constituting the coloring layer (B). Is more preferable. As long as the lower limit of the amount of regenerated additives is applied, it is possible to reduce costs by reusing resources. On the other hand, the upper limit is preferably 30% by mass or less, more preferably 25% or less, from the viewpoint of maintaining the transparency of the laser color-developing sheet.

<Sheet characteristics>
Hereinafter, the characteristics of each sheet and the layers constituting each sheet will be described in detail.

The laser color-developing sheet of the present invention preferably has a tensile elongation at break (TD) of 80% or more, more preferably 90% or more, and even more preferably 100% or more in accordance with JIS K7127. .. Usually, polyester-based resins tend to be oriented in the extrusion direction (MD), and the elongation of TD tends to decrease accordingly. In order to adjust the tensile elongation at break to a desired range, a method of adjusting the line speed during film formation or an impact improver (a2) is added to the polyester resin (a1) constituting the adhesive layer (A). The method of doing this can be mentioned. When the tensile elongation at break is in the above range, excellent mechanical properties can be imparted to the card.

As described above, the temperature of heat fusion is preferably in the range of 120 ° C. to 160 ° C., more preferably in the range of 130 ° C. to 160 ° C., and further preferably in the range of 130 ° C. to 150 ° C. preferable.

In the sublimation type thermal transfer image receiving layer (C) after heat fusion, the chromaticity b * value measured in accordance with JIS Z8781-4 has a Δb * calculated based on the following formula (1). It is preferably less than 00.

Δb * = (b * after heat fusion)-(b * before heat fusion) ... (1)

If Δb * is less than 1.00, the characters and images laser-printed on the laser color-developing sheet (A) will not be blurred due to the coloring of the card after heat fusion. Further, the characters and images printed on the sublimation type thermal transfer image receiving layer (C) are not blurred. From this point of view, Δb * is more preferably less than 0.70, and even more preferably less than 0.50.

<Card>
The card is obtained by heat-sealing the laser color-developing sheet of the present invention and at least one layer of the core sheet for a card.
Generally, a card is composed of, for example, an oversheet used for the surface layer of the card, a core sheet used for the middle layer, an intermediate sheet arranged between the oversheet and the core sheet, and the like. Generally, a card is made by superimposing a transparent oversheet on a printed white core sheet, and if necessary, an intermediate sheet, heat-sealing the sheets with a hot press, and then using a punching blade. It is manufactured by cutting it into a shape and, in some cases, finally engraving it with an embosser. Further, a magnetic stripe, an IC chip, an antenna coil, or the like for recording information may be provided.

Here, FIG. 2A exemplifies a card provided with the laser color-developing sheet (10) and the core sheet (30) of the present invention. FIG. 2B illustrates a card (21) in which a core sheet (30) and an oversheet (20) are provided on the laser color-developing sheet (10) of the present invention.
Further, in FIGS. 3A and 3B, in the card using the laser color-developing sheet of the present invention, a card further provided with a sublimation type thermal transfer image receiving layer (40) is illustrated.

Hereinafter, the core sheet and the oversheet will be described in order.

<Core sheet for cards>
As the core sheet for a card (hereinafter referred to as a core sheet) used in the method for manufacturing a card of the present invention, a commonly used one can be used. As the material for forming the core sheet, for example, a thermoplastic resin that is deformed by heating and pressurizing is preferably used. Examples of the thermoplastic resin include general-purpose plastics such as polyolefin resins, amorphous polyester resins, crystalline polyester resins, acrylic resins, ABS resins, AS resins, polycarbonate resins, PVC resins, and biodegradable resins. Be done. In addition to this, engineering plastics having good heat resistance can be used. Examples of engineering plastics include polyphenylene sulfide, polyetherimide, polyimide, and polyetheretherketone. A film or sheet made of a material containing one or more of these as main components is preferably used as a core sheet.
The core sheet may be a single layer or a laminated body having two or more layers.

The core sheet may be transparent, translucent or opaque, and may be colored white or chromatic. It is preferable to appropriately select it according to the intended use. When the core sheet is a translucent sheet or an opaque sheet, an inorganic pigment or an organic pigment can be blended in the resin forming the core sheet. Even in the case of a transparent sheet, the pigment can be blended in an amount within a range that does not impair the transparency. Various additives such as a plasticizer and an antistatic agent can be added to the core sheet, if necessary.
Further, it is preferable that the surface of the core sheet is embossed or the like so that deaeration can be easily performed when joining with an oversheet or other sheets described later.

Generally, the thickness of the core sheet is preferably 100 μm to 800 μm, and more preferably 200 μm to 600 μm.

As a method for forming the core sheet, the method of the laser color-developing sheet described above can be adopted. The constituent materials may be supplied to an extruder and extruded in a single layer, or in the case of lamination, a coextrusion method can be adopted.

<Card oversheet>
As the card oversheet (hereinafter, referred to as oversheet) used in the card manufacturing method of the present invention, those generally used conventionally can be used. Examples of the material for forming the oversheet include PVC-based resin, ABS resin, amorphous polyester-based resin, crystalline polyester-based resin, polycarbonate-based resin, acrylic resin, and biodegradable resin. The oversheet may be attached to the core sheet or other sheet by using an adhesive, but it is preferably attached to the core sheet or other sheet by heat fusion or the like by heating and pressurizing. Therefore, it is preferable to select a material that can be heat-sealed with a core sheet or the like. Further, for the oversheet, it is preferable to select a material having visible light transmission so that a layer arranged on the back side, for example, an image formed on an intermediate sheet or the like can be visually recognized. The oversheet may be a single layer or a laminated body having two or more layers.

In general, the thickness of the oversheet is preferably 50 μm to 200 μm, more preferably 75 μm to 150 μm.

If necessary, the oversheet may contain additives such as colorants, lubricants, fillers, and impact improvers, or may be blended with dissimilar polymers for improving physical properties.
Especially in the case of cards that are embossed to engrave letters, such as credit cards, the oversheet should be a plate-like filler such as talc or a polymer that reduces tensile strength such as polybutylene terephthalate. It is preferable to blend.

As a method for forming the oversheet, the above-mentioned laser color-developing sheet and core sheet methods can be adopted.

The laser color-developing sheet of the present invention can be used as the oversheet, or can be used as an intermediate sheet arranged between the oversheet and the core sheet.

<Card manufacturing method>
A method for manufacturing a card using the laser color-developing sheet of the present invention is to heat-fuse the laser color-developing sheet of the present invention with at least one layer of a core sheet for a card. If necessary, an overseat may be further provided. As an example, a method for manufacturing a card having a layer structure of a laser color-developing sheet / core sheet / oversheet is shown below.

A laser color-developing sheet is placed on one surface of the core sheet, and an oversheet is placed on the other surface of the core sheet. After they are heat-sealed to form a laminate, the laminate can be punched into a card shape to produce a card. Here, the heat fusion means that the heat fusion is performed by heating and pressurizing, and the temperature of the heat fusion is preferably in the range of 120 ° C. to 160 ° C. When the heat fusion temperature is in the range of 120 ° C. to 160 ° C., fusion at a low temperature becomes possible, and for example, a curd that does not cause yellowing after heat fusion can be manufactured. From this point of view, the temperature of heat fusion is more preferably in the range of 130 ° C. to 160 ° C., and further preferably in the range of 130 ° C. to 150 ° C.

Examples of the method of heating and pressurizing include, but are not limited to, a press method, a laminating method, and the like, and it is preferable that the method is appropriately selected according to the material of the sheet to be used. The layer structure of the card is not limited to the above.

<Characteristics of the card>
The card using the laser color-developing sheet of the present invention preferably has a dynamic bending force of 40,000 times or more measured in accordance with JIS X6305-1. This makes it possible to impart excellent mechanical properties to the card. From this point of view, the dynamic bending force measured according to JIS X6305-1 is more preferably 50,000 times or more, and further preferably 60,000 times or more.

<Explanation of terms>
In the present invention, the sheet refers to a product that is thin by definition in JIS and whose thickness is generally small for its length and width and is flat. By the way, a film is a thin flat product whose thickness is extremely small compared to its length and width and whose maximum thickness is arbitrarily limited, and is usually supplied in the form of a roll (JISK6900). Therefore, it can be said that a film has a particularly thin thickness among the sheets, but the boundary between the sheet and the film is not clear and it is difficult to clearly distinguish them. Therefore, in the present application, even if the term "sheet" is used, the term "film" is used. Shall include.

In the present invention, the term "main component" includes the meaning of allowing other components to be contained within a range that does not interfere with the function of the main component, unless otherwise specified. Further, although the content ratio of the main component is not specified, unless otherwise specified, the main component is 50% by mass or more, preferably 70% by mass or more, particularly preferably 90% by mass or more (100%) in the composition. Includes the meaning of occupying). When two or more kinds of resins constitute the main component, the ratio of each resin in the composition is 10% by mass or more, preferably 20% by mass or more, and particularly preferably 30% by mass or more.

Further, when expressed as "X to Y" (X, Y are arbitrary numbers) in the present invention, unless otherwise specified, it means "X or more and Y or less" and "preferably larger than X" or "preferably larger than X". It also includes the meaning of "smaller than Y".
Furthermore, when expressed as "X or more" (X is an arbitrary number) or "Y or less" (Y is an arbitrary number), it means "preferably larger than X" or "preferably less than Y". Also includes the intention of.

Examples will be shown below and the present invention will be described in more detail. However, the present invention is not limited thereto, and various applications are possible without departing from the technical scope of the present invention.

<Measurement and evaluation method>
First, a method for measuring and evaluating various physical property values of the samples obtained in Examples and Comparative Examples will be described.

Tensile breaking elongation The tensile breaking elongation of the TD of the laser color-developing sheet was measured according to JIS K7127.

Dynamic bending force The dynamic bending force of the card produced using the laser color-developing sheet was measured according to JIS X 6305-1.

Laser printability Regarding the laser printability of the card produced using the laser color-developing sheet, printing was performed using LM-20 manufactured by Nidec Copal Corporation at a resolution of 400 dpi and 500 dpi and a laser output of 60%.
◯: Clear printing is possible ×: Printing is not possible

Heat-fused laser color-developing sheet and core sheet with a thickness of 160 μm (PC: PETG: titanium oxide = 55: 33: 12 by mass ratio) are stacked in the order of laser color-developing sheet / core sheet / laser color-developing sheet. After that, at each temperature shown in Table 1, the sample heated and fused at a press pressure of 4 Mpa and a heating time of 2 minutes was cooled at a press pressure of 5 Mpa and a cooling time of 5 min, and the sample was cooled at the laminated interface at the edge of the sheet. The fusion property at the time of peeling was evaluated according to the following criteria.
◯: Material was destroyed without peeling.
Δ: Partial fusion peels off halfway (5 mm or more from the end) or peels off to the end when force is applied ×: Peeled without fusion

Δb *
The chromaticity b * of the sample evaluated by heat fusion in (3) above was measured using a spectrophotometer manufactured by Konica Minolta Co., Ltd., and calculated based on the following formula (1). The b * value before and after heat fusion was measured based on the following description.
Δb * = (b * value after heat fusion)-(b * value before heat fusion) ... (1)
(B * value before heat fusion): Arbitrary three points were measured and averaged for a sample in which a laser color-developing sheet (A) having a sublimation transfer printing image receiving layer (c) and a core sheet (B) were overlapped. The value was calculated.
(B * value after heat fusion): Any 3 of a sample in which a laser color-developing sheet (A) having a sublimation transfer printing image receiving layer (c) and a core sheet (B) are heat-sealed at a predetermined temperature. The points were measured and the average value was calculated.

(Example 1)
As a thermoplastic resin for the adhesive layer (A-1), a polyester resin "a1" having an alicyclic structure as a diol component (100 mol% of terephthalic acid as an acid component and 78 mol of 1,4-cyclohexanedimethanol as a diol component). %, 2,2,4,4-tetramethyl-1,3-cyclobutanediol (polyester containing 22 mol%) and impact improver "a2" (multilayer containing 80% by mass of styrene with respect to all the components constituting the shell layer) (Structural polymer) is mixed and used in a weight ratio of a1: a2 = 88: 12, and a polycarbonate resin (interfacial polymer PC, weight average molecular weight: about 58500) is used as a resin composition for the coloring layer (B-1). ) A polycarbonate-based resin in which 0.15 parts by mass of bismuth-neodium-based metal oxide was added to 100 parts by mass was used. These resin compositions were put into each hopper of two extruders, melted at a set temperature of 235 ° C., and co-extruded to obtain a laminated sheet (laser color-developing sheet) having a two-kind, three-layer structure. .. The obtained laser color-developing sheet had an adhesive layer (A-1) / color-developing layer (B-1) / adhesive layer (A-1) = 17 μm / 66 μm / 17 μm, and had a total thickness of 100 μm. Table 1 shows the tensile elongation at break of the obtained laser color-developing sheet.
Next, after stacking the obtained laser color-developing sheet and a PETG core sheet having a thickness of 650 μm as a core sheet, a press temperature of 140 ° C., a press pressure of 1 MPa, a residual heat time of 5 minutes, a press pressure of 5 MPa, and a heating time of 1 A heat press was carried out under the condition of minutes to obtain a laminate for forming a card.
Next, the obtained laminate for forming a card was punched into a card shape to prepare a card. Table 1 shows the dynamic bending force and laser printability of the obtained card.

(Example 2)
A sublimation type obtained by preparing a curd in the same manner as in Example 1 and then mixing a vinyl chloride / vinyl acetate copolymer and a MEK / cyclohexane mixed solvent in a mass ratio of a copolymer: mixed solvent 20:80. A card was prepared in the same manner as in Example 1 except that the heat transfer image receiving layer (C-1) was provided so as to have a thickness of 2 μm after drying.

(Example 3)
As the thermoplastic resin for the color-developing layer of Example 1, a recycled resin obtained by reusing a film generated in the manufacturing process is added, and the ratio of polycarbonate resin: recycled resin to polycarbonate resin: recycled resin = 80:20. Cards were prepared in the same manner as in Example 1 except that they were mixed and used in.

(Comparative Example 1)
Polyester resin "a1" having an alicyclic structure as a diol component (100 mol% of terephthalic acid as an acid component, 78 mol% of 1,4-cyclohexanedimethanol as a diol component, 2,2,4,4-tetramethyl-1 , 3-Cyclobutanediol (polyester containing 22 mol%) was put into a hopper of an extruder, melted at a set temperature of 250 ° C. and extruded, and then a 100 μm single-layer sheet (A-2) was obtained. Further, a polycarbonate resin obtained by adding 0.15 parts by mass of bismuth / neodium metal oxide to 100 parts by mass of a polycarbonate resin (interfacial polymerized PC, weight average molecular weight: about 58500) was put into the hopper of the extruder. After melting and extruding at a set temperature of 250 ° C., a 50 μm single-layer sheet (B-2) was obtained. The obtained sheets were stacked in the order of (A-2) / (B-2) / (A-2), and the press temperature was 160 ° C., the press pressure was 1 MPa, the residual heat time was 5 minutes, the press pressure was 5 MPa, and the heating time was 1 minute. A heat press was performed under the conditions to obtain a laser color-developing sheet. The obtained laser color-developing sheet had an adhesive layer (A-2) / color-developing layer (B-2) / adhesive layer (A-2) = 100 μm / 50 μm / 100 μm, and had a total thickness of 250 μm. Table 1 shows the tensile elongation at break of the obtained laser color-developing sheet.
After stacking the obtained laser color-developing sheet and a PETG core sheet as a core sheet, a heating press is performed under the conditions of a press temperature of 160 ° C., a press pressure of 1 MPa, a residual heat time of 5 minutes, a press pressure of 5 MPa, and a heating time of 1 minute. Was carried out to obtain a laminated body for forming a card.
Next, the obtained laminate for forming a card was punched into a card shape to prepare a card. Table 1 shows the dynamic bending force and laser printability of the obtained card.

(Comparative Example 2)
As the thermoplastic resin for the adhesive layer (A-3), with respect to a non-crystalline aromatic polyester resin (a polyester resin in which about 30 mol% of ethylene glycol in polyethylene terephthalate is replaced with 1,4-cyclohexanedimethanol). Using a resin composition containing 0.8% of a lubricant, as a resin composition for a coloring layer (B-3), a bismus-neodium-based metal with respect to 100 parts by mass of a polycarbonate resin containing 0.24 wt% of an antioxidant. A polycarbonate resin to which 0.05 parts by mass of an oxide was added was used. These resin compositions are put into each hopper of the two extruders, melted at a set temperature of the adhesive layer of 230 ° C. and a set temperature of the coloring layer at 235 ° C., co-extruded, and then composed of two types and three layers. (Laser color-developing sheet) was obtained. The obtained laser color-developing sheet had an adhesive layer (A-3) / color-developing layer (B-3) / adhesive layer (A-3) = 25 μm / 50 μm / 25 μm, and had a total thickness of 100 μm. Table 1 shows the tensile elongation at break of the obtained laser color-developing sheet.
After stacking the obtained laser color-developing sheet and a PETG core sheet as a core sheet, a heating press is performed under the conditions of a press temperature of 130 ° C., a press pressure of 1 MPa, a residual heat time of 5 minutes, a press pressure of 5 MPa, and a heating time of 1 minute. Was carried out to obtain a laminated body for forming a card.
Next, the obtained laminate for forming a card was punched into a card shape to prepare a card. Table 1 shows the dynamic bending force and laser printability of the obtained card.

(Reference example 1)
Polycarbonate resin (interfacial polymerization PC, weight average molecular weight of about 81000) was put into each hopper of two extruders, melted at a set temperature of 280 ° C., co-extruded, and then a single-layer sheet having a total thickness of 70 μm was obtained. rice field. Table 1 shows the tensile elongation at break of the obtained sheet.
Further, the sublimation transfer image receiving layer is applied in the same manner as in Example 2, and the obtained sheet and the PETG core sheet as the core sheet are superposed, and then the press temperature is 175 ° C., the press pressure is 1 MPa, the residual heat time is 5 minutes, and the press is performed. A heat press was carried out under the conditions of a pressure of 5 Mpa and a heating time of 1 minute to obtain a laminate for forming a card.
Next, Table 1 shows the dynamic bending force of the card obtained by punching the obtained laminate for card formation into a card shape.

(Discussion)
The cards obtained by using the laser color-developing sheets of Examples 1 to 3 were excellent in low-temperature fusion property, excellent in mechanical properties, and did not change in color even when a sublimation transfer printing image receiving layer was provided. Furthermore, it was possible to obtain a card in which the mechanical properties and the laser printing performance were not deteriorated even when the recycled resin was added to the color-developing layer.
On the other hand, in the mode in which the adhesive layer (A) does not contain an impact improving agent, the value of tensile elongation at break is low and the mechanical properties of the laser color-developing sheet are inferior (Comparative Example 1). Further, the card in which the adhesive layer (A) is made of PETG has a low value of dynamic bending force and is inferior in mechanical properties as a card (Comparative Example 2). Further, when the adhesive layer (A) is made of polycarbonate resin, a card cannot be formed by low temperature fusion, and in the case of high temperature fusion at 180 ° C. and 190 ° C., the Δb * value of the sublimation transfer printing image receiving layer. Was high (Reference Example 1).

1 Adhesive layer 2 Color development layer 10 Laser color development sheet 20 Oversheet 30 Core sheet 40 Sublimation type thermal transfer image receiving layer

Claims (22)

A laser color-developing sheet formed from at least two sheets having an adhesive layer (A) and a color-developing layer (B).
The adhesive layer (A) contains a polyester-based resin (a1) and an impact improver (a2) containing a diol component having at least one alicyclic structure selected from spiroglycol and isosorbide, and is said to be polyester-based. The mass ratio of the resin (a1) to the impact improver (a2) is (a1) / (a2) = 60/40 to 90/10.
A laser color-developing sheet, wherein the color-developing layer (B) contains 0.01 to 10 parts by mass of a laser light energy absorber with respect to 100 parts by mass of a polycarbonate resin. The laser color-developing sheet according to claim 1, further comprising a sublimation type thermal transfer image receiving layer (C) on at least one surface of the adhesive layer (A) or the color-developing layer (B). A laser color-developing sheet formed from at least two sheets having an adhesive layer (A) and a color-developing layer (B).
A polyester-based adhesive layer (A) containing a diol component having at least one alicyclic structure selected from spiroglycol, isosorbide, and 2,2,4,4-tetramethyl-1,3-cyclobutanediol. It contains the resin (a1) and the impact improver (a2), and the mass ratio of the polyester resin (a1) and the impact improver (a2) is (a1) / (a2) = 60/40 to 90/10. can be,
The color-developing layer (B) contains 0.01 to 10 parts by mass of the laser light energy absorber with respect to 100 parts by mass of the polycarbonate resin.
A laser color-developing sheet, which further has a sublimation type thermal transfer image receiving layer (C) on at least one surface of the adhesive layer (A) or the color-developing layer (B). The laser color-developing sheet according to any one of claims 1 to 3, wherein the diol component having an alicyclic structure is 5 to 40 mol% with respect to the total amount of the diol component of the polyester resin (a1). The impact modifier (a2) is a laser color developing sheet according to any one of the configured multi-layered polymer der Ru請Motomeko 1-4 core layer and one or more shell layer covering it. The laser color-developing sheet according to claim 5, wherein the content of the aromatic vinyl-based unit with respect to all the components constituting the shell layer is 50% by mass or more. The laser color-developing sheet according to any one of claims 1 to 6 , wherein the laser light energy absorber contains a bismuth / neodymium-based oxide. The laser color- developing sheet according to any one of claims 1 to 7 , wherein the adhesive layer (A) or the color-developing layer (B) contains a recycled resin obtained by reusing a sheet generated in a manufacturing process. The laser color-developing sheet according to any one of claims 1 to 8 , wherein the tensile elongation at break (TD) measured according to JIS K7127 is 80% or more. A card using the laser color-developing sheet according to any one of claims 1 to 9. A card having a laser color-developing sheet formed from at least two sheets having an adhesive layer (A) and a color-developing layer (B), a core sheet for a card having at least one layer, and an oversheet.
A polyester-based adhesive layer (A) containing a diol component having at least one alicyclic structure selected from spiroglycol, isosorbide, and 2,2,4,4-tetramethyl-1,3-cyclobutanediol. It contains the resin (a1) and the impact improver (a2), and the mass ratio of the polyester resin (a1) and the impact improver (a2) is (a1) / (a2) = 60/40 to 90/10. can be,
A card characterized in that the color-developing layer (B) contains 0.01 to 10 parts by mass of a laser light energy absorber with respect to 100 parts by mass of a polycarbonate resin. The card according to claim 10 or 11 , wherein the dynamic bending force measured according to JIS X 6305-1 is 40,000 times or more. A method for producing a laser color-developing sheet formed from at least two sheets having an adhesive layer (A) and a color-developing layer (B).
Impact improvement with polyester resin (a1) containing a diol component having at least one alicyclic structure selected from spiroglycol, isosorbide, and 2,2,4,4-tetramethyl-1,3-cyclobutanediol. An adhesive layer (A) containing an agent (a2) and having a mass ratio of the polyester resin (a1) to the impact improving agent (a2) (a1) / (a2) = 60/40 to 90/10. The process of forming and
A step of forming a color-developing layer (B) containing 0.01 to 10 parts by mass of a laser light energy absorber with respect to 100 parts by mass of a polycarbonate resin.
A step of laminating the adhesive layer (A) on at least one side of the color-developing layer (B), and
A method for producing a laser color-developing sheet. A method for producing a laser color-developing sheet formed from at least two sheets having an adhesive layer (A) and a color-developing layer (B).
A laser color-developing sheet in which a resin composition (X) for forming an adhesive layer (A) and a resin composition (Y) for forming a color-developing layer (B) are supplied to an extruder and co-extruded and laminated. Manufacturing method.
Resin composition (X); polyester-based containing spiroglycol, isosorbide, and a diol component having at least one alicyclic structure selected from 2,2,4,4-tetramethyl-1,3-cyclobutanediol. It contains the resin (a1) and the impact improver (a2), and the mass ratio of the polyester resin (a1) and the impact improver (a2) is (a1) / (a2) = 60/40 to 90/10. A resin composition Resin composition (Y); A resin composition containing 0.01 to 10 parts by mass of a laser light energy absorber with respect to 100 parts by mass of a polycarbonate resin. The method for producing a laser color- developing sheet according to claim 13 or 14 , wherein the diol component having an alicyclic structure is 5 to 40 mol% with respect to the total amount of the diol component of the polyester resin (a1). The impact improver (a2) is a multilayer structure polymer composed of a core layer and one or more shell layers covering the core layer, and the content of aromatic vinyl-based units with respect to all the components constituting the shell layer is 50. The method for producing a laser color-developing sheet according to any one of claims 13 to 15 , which is by mass or more. The method for producing a laser color-developing sheet according to any one of claims 13 to 16 , wherein the laser light energy absorber contains a bismuth / neodymium-based oxide. The method for producing a laser color- developing sheet according to any one of claims 13 to 17 , wherein the adhesive layer (A) or the color-developing layer (B) contains a recycled resin obtained by reusing a sheet generated in the production process. The laser color-developing sheet according to any one of claims 13 to 18 , further forming a sublimation type thermal transfer image receiving layer (C) on at least one surface of the adhesive layer (A) or the color-developing layer (B). Production method. The method for producing a laser color-developing sheet according to any one of claims 13 to 19 , wherein the tensile elongation at break (TD) measured in accordance with JIS K7127 is 80% or more. A method for manufacturing a card having a laser color-developing sheet formed from at least two sheets having an adhesive layer (A) and a color-developing layer (B) and a core sheet for a card having at least one layer.
A polyester-based adhesive layer (A) containing a diol component having at least one alicyclic structure selected from spiroglycol, isosorbide, and 2,2,4,4-tetramethyl-1,3-cyclobutanediol. It contains the resin (a1) and the impact improver (a2), and the mass ratio of the polyester resin (a1) and the impact improver (a2) is (a1) / (a2) = 60/40 to 90/10. can be,
The color-developing layer (B) contains 0.01 to 10 parts by mass of the laser light energy absorber with respect to 100 parts by mass of the polycarbonate resin.
A method for manufacturing a card, which comprises fusing the laser color-developing sheet and the core sheet for the card. The method for manufacturing a card according to claim 21 , wherein the dynamic bending force measured according to JIS X 6305-1 is 40,000 times or more.

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