JP3925736B2 - Thermally adhesive white polyester film for IC card or IC tag, IC card or IC tag manufacturing method using the same, and IC card or IC tag - Google Patents

Description

  The present invention relates to a heat-adhesive white polyester film suitable as a constituent material for an IC card or IC tag, a method for producing an IC card or IC tag using the same, and an IC card or IC tag.

  In recent years, information management and operation systems using cards and tags with built-in IC chips have begun to spread. The cards and tags used for these are generally called "IC cards" and "IC tags", and can record and retain a large amount of information compared to conventional printing / writing and magnetic recording cards / tags. Therefore, it is beginning to be used in various fields for managing and operating various information on people and goods.

  Conventionally, polyvinyl chloride (PVC) has been mainstream as a plastic material constituting an IC card or IC tag. However, in recent years, there has been an increasing demand from the market for a material that does not use halogens from the viewpoint of environmental issues, and the card material has been mainly replaced by a polyester resin. As a sheet or film made of a polyester resin, a non-oriented sheet made of a copolymerized polyester (PETG) containing 1,4-cyclohexanedimethanol as a copolymerization component from the viewpoint of being amorphous and having processing characteristics close to PVC, or From the viewpoint of versatility, a biaxially stretched polyethylene terephthalate (PET) film is mainly used. However, these current sheets and films have problems that are difficult to solve.

  For example, in the case of a non-oriented PETG sheet, the heat resistance is insufficient. This is because the molecular chains of the polyester constituting the sheet are not stretched and oriented, so that when the sheet is heated, it softens and deforms rapidly near the glass transition temperature. Therefore, if an IC card or IC tag is left on a car dashboard for a long time under hot weather, it will be stored in a pocket of clothes, etc., and if it is accidentally washed or hot-air dried, it will be stored in the cargo ship's hold etc. When exported to the tropical region, the IC card or IC tag may be damaged in appearance and function due to dimensional changes, deformation, curling, peeling, etc. caused by heat.

  In order to improve this heat resistance, a non-oriented sheet obtained by adding polycarbonate or the like to PETG may be used in recent years. However, this sheet is slightly inferior in chemical resistance, and when a solvent-based adhesive or solvent-based ink is used during the manufacture of an IC card or IC tag, deformation or discoloration may occur, which impairs the appearance or function. there were.

  On the other hand, the biaxially stretched PET film is excellent in terms of chemical resistance and heat resistance. However, since the biaxially stretched PET film has a large elastic modulus and does not easily deform, it cannot absorb irregularities caused by the internal structure (IC chip, circuit, etc.) of the IC card or IC tag, and the shape of the chip or circuit Has a problem that the surface of the IC card or IC tag is raised. If such irregularities are present on the surface of the IC card or IC tag, it goes without saying that the appearance is not beautiful, and that the printed surface may be scratched or caught by other items caused by rubbing with other items generated during carrying. In some cases, the surface layer may be peeled off and the appearance and functions may be impaired.

  Biaxially stretched PET films do not have self-adhesive properties like PVC sheets and PETG sheets and do not adhere by hot pressing or thermal lamination. For this reason, in order to manufacture an IC card or an IC tag by laminating biaxially stretched PET films, a hot melt adhesive or the like must be inserted between the films and processed. Therefore, the process of forming an IC card or IC tag using a biaxially oriented film is complicated, and there is a problem that workability and yield are deteriorated.

  In order to compensate for the disadvantages of these materials, a method has been proposed in which a biaxially stretched PET film and a non-oriented PETG sheet are bonded together. However, in order to bond them together, it is necessary to use a hot melt adhesive, and the above problem has not been solved yet. In general, with a non-oriented PETG sheet, it is difficult to manufacture a thin sheet with high accuracy. Moreover, the non-oriented PETG sheet normally distributed on the market has a thickness exceeding 100 μm. For this reason, a non-oriented PETG sheet occupies most of the ratio of the thickness which comprises an IC card or an IC tag. Therefore, even when the non-oriented PETG sheet is laminated as described above, the heat resistance of the entire card is not sufficiently improved. Furthermore, the process of bonding a plurality of films and sheets is required. Therefore, the manufacturing process becomes complicated, which is not preferable in terms of quality stability and manufacturing cost.

  The present invention has an excellent balance of heat resistance, chemical resistance, unevenness absorbability, and thermal adhesiveness compared to the conventional method of laminating a biaxially stretched PET film and a non-oriented PETG sheet. The present invention proposes a heat-adhesive white polyester film obtained by laminating a specific heat-adhesive layer on one or both sides of a white biaxially stretched polyester film containing one or both of the above.

As a film having a layer structure similar to the present invention, a heat-adhesive polyester film mainly used for a packaging material has been conventionally used. For example, inventions relating to the following heat-adhesive polyester film are disclosed.
(1) A film for heat-insulating packaging material comprising a structure in which a polybutylene terephthalate / polytetramethylene oxide copolymer is laminated on the surface of a void-containing polyester film (see, for example, Patent Document 1)
(2) Film for packaging material or electrical insulation film comprising a structure in which a mixture of crystalline polyester and low crystalline copolymer polyester is laminated on the surface of the polyester film (for example, see Patent Document 2)
(3) Film for packaging material formed by laminating a resin obtained by mixing two kinds of copolymer polyester resins on the surface of a polyester film (see, for example, Patent Documents 3 to 4)
(4) Films for packaging materials or printing materials in which a resin obtained by mixing at least one type of copolymer polyester resin is applied to the surface of a void-containing polyester film (for example, see Patent Documents 5 to 6)
(5) Metal plate laminate or film for packaging material in which a mixture of a copolyester resin and silica particles is laminated on the surface of a polyester film (for example, see Patent Documents 7 to 10)
(6) Capacitor film in which a copolymer polyester resin or copolymer urethane resin and a mixture of silica particles, calcium carbonate particles, zeolite particles, or the like are applied to the surface of the polyester film (see, for example, Patent Documents 11 to 14)

JP-A-56-4564 JP 58-12153 A JP-A-1-237138 Japanese Patent No. 3484695 Japanese Patent No. 3314814 Japanese Patent No. 3314816 JP-A-7-132580 JP 2001-293932 A JP 2004-188622 A JP 2004-203905 A JP 2000-30969 A JP 2001-307945 A JP 2002-79637 A JP 2003-142332 A

  Although these inventions are similar in structure, they do not satisfy the unevenness absorbability which is one of the problems of the heat-adhesive white polyester film of the present invention. That is, in the invention (Patent Documents 2 and 7 to 10) in which crystalline copolyester is used as a main component of the thermal adhesive layer, the thermal adhesive layer is not sufficiently deformed. Therefore, the unevenness absorbability necessary for use as a core sheet of an IC card or IC tag is insufficient.

  On the other hand, in the invention (Patent Documents 5, 6, 11 to 14) in which the thermal adhesive layer is provided by the coating method, the thickness of the thermal adhesive layer is thin, so that the unevenness necessary for use as a core sheet of an IC card or IC tag Absorbability is insufficient.

  On the other hand, in the invention (Patent Documents 1, 3, and 4) in which amorphous copolyester is used as a main component of the thermal adhesive layer, the unevenness absorbability is improved by increasing the thickness of the thermal adhesive layer. . However, as the thickness of the thermal adhesive layer is increased, the slipperiness of the film is deteriorated, and the slipperiness desired in handling a normal film cannot be obtained. Furthermore, when the thickness of the thermal adhesive layer is increased, the composition of the base material and the thermal adhesive layer is different, so that the film tends to curl immediately after the production of the film, after storage, and when heat-treated in a post-processing step. Therefore, special care is required for controlling the curl (flatness) of the film. However, curl cannot be controlled stably within the scope of the technique described in the above-mentioned patent document.

  That is, with the conventional technology, it has been difficult to achieve both uneven absorbability, thermal adhesiveness, and slipperiness. The technical reason is considered as follows.

  Usually, when unevenness is to be absorbed by deformation of the resin, it is advantageous to use an amorphous resin. From the viewpoint of thermal adhesiveness, it is advantageous to use a resin having a moderately low degree of crystallization and a low softening temperature.

  However, when manufacturing a biaxially stretched film using such a resin, it is known that it is difficult to express slipperiness. That is, even if the method of incorporating inorganic particles or organic particles having a size of several μm or less, which is generally used for improving the slipperiness of the film, into the film, the amorphous resin is used as the film raw material. In the used biaxially stretched film, sufficient unevenness cannot be obtained on the film surface. Therefore, the slipperiness of the film becomes insufficient.

  The cause of this is not clear, but the resin having low crystallinity is in a state substantially close to melting in the step of heat-setting the stretched film. At this time, it is considered that the surface tension acts so as to reduce the surface roughness, that is, the surface free energy, by reducing the unevenness of the film surface, and the particles are buried in the resin.

  In addition, in order to improve the slipperiness, when using particles having a large particle size, a high protrusion caused by the large particles generates a region where contact is poor in the background portion of the film, and the thermal adhesiveness is sufficient. It may not develop. Furthermore, in the film manufacturing process or processing process, large particles may fall off and contaminate the manufacturing process, or the strength of the film or sheet may decrease.

  On the other hand, in a non-oriented sheet represented by a non-oriented PETG sheet, macroscopic unevenness can be formed by embossing the sheet itself, and slipperiness can be expressed. However, when a biaxially stretched polyester film having excellent chemical resistance and heat resistance is used as in the present invention, since it is a rigid film, embossing itself is difficult, and it is the same as a non-oriented sheet. This method could not be used.

The object of the present invention is to improve thermal adhesion, unevenness absorbability, and slipperiness while maintaining environmental suitability (not containing halogen), heat resistance, and chemical resistance as a plastic material for IC cards or IC tags. And providing a heat-adhesive white polyester film for an IC card or IC tag . Furthermore, in addition to the above-described problems, an IC card or a heat-adhesive white polyester film for IC tags having small curl and excellent flatness is also provided.

The first invention in the present invention that can solve the above-mentioned problems is based on a white biaxially stretched polyester film containing one or both of a white pigment and fine cavities inside, and one or both sides of the substrate. And a heat-adhesive white polyester film obtained by laminating a heat-adhesive layer, wherein the heat-adhesive white polyester film contains a large number of fine cavities inside the film, and (a) the apparent density of the film is 0.7 to 1.3 g / cm ³ , (b) thickness of 50 to 350 μm, (c) optical density of 0.5 to 3.0, the thermal adhesive layer has a thickness of 5 to 30 μm, and a glass transition temperature of 50 to It consists of a mixture of an amorphous polyester resin A at 95 ° C. and a thermoplastic resin B incompatible with it, and the thermoplastic resin B is a crystalline resin having a melting point of 50 to 180 ° C. ~ 30% by mass An IC card or thermoadhesive polyester film IC tag, wherein are.

In the second invention, a heat-adhesive white polyester film has a heat-adhesive layer laminated on both sides of a biaxially stretched polyester film, one heat-adhesive layer as a heat-adhesive layer a, and the other heat-adhesive layer b (thickness is The thickness ratio of the thermal adhesive layer (the thickness of the thermal adhesive layer a / the thickness of the thermal adhesive layer b) is 1.0 to 2 when the thermal adhesive layer a is the same as or thinner than the thermal adhesive layer a). 0.0 and the curl value after heat treatment of the film (110 ° C., 30 minutes under no load) is 5 mm or less, the thermal adhesiveness for IC card or IC tag according to the first invention It is a white polyester film.

A third invention is characterized in that the surface of the thermal adhesive layer satisfies the following formulas (1) to (3), wherein the thermal adhesive white polyester film for IC card or IC tag according to the first or second invention is provided. It is.
1.0 ≦ St1 ≦ 10.0 (1)
3.0 ≦ St1 / Sa1 ≦ 20 (2)
0.001 ≦ St2 ≦ 3.000 (3)
In the above formulas (1) to (3), Sa1 means the arithmetic average surface roughness of the surface of the thermal adhesive layer, and St1 means the maximum height. St2 is a thermal adhesive layer after a film is sandwiched between two clean glass plates having an arithmetic average surface roughness of 0.001 μm or less and subjected to a hot press treatment at a temperature of 100 ° C. and a pressure of 1 MPa for 1 minute. Means the arithmetic average surface roughness of the surface. The unit of Sa1, St1, and St2 is all μm.

4th invention is the static friction coefficient measured by superimposing one side and the other side of a heat-adhesive white polyester film, and is any one of 1st- 3rd invention characterized by the above-mentioned. It is a heat-adhesive white polyester film for IC cards or IC tags as described.

5th invention arrange | positions the heat adhesive film in any one of 1st- 4th invention on the single side | surface or both surfaces of the inlet which provided the antenna circuit and IC chip in the plastic film, and heat | fever the heat adhesive film. An IC card or IC tag manufacturing method, characterized in that a core sheet obtained by hot pressing an inlet through an adhesive layer is used as a constituent element.

According to a sixth aspect of the present invention, the thermal adhesive film according to any one of the first to fourth aspects is laminated on one or both sides of an inlet provided with an antenna circuit and an IC chip on a plastic film, and the heat of the thermal adhesive film is increased. An IC card or an IC tag comprising a core sheet bonded to an inlet through an adhesive layer as a constituent element.

A seventh invention is the IC card or IC tag according to the sixth invention, wherein a polyester sheet or a biaxially stretched polyester film is laminated on both surfaces of the core sheet.

  The heat-adhesive white polyester film of the present invention has not been able to be achieved by various materials and heat-adhesive films for conventional IC cards, (a) irregularity absorbability, environmental suitability (not containing halogen), and heat resistance. , Chemical resistance, (b) uneven absorption and thermal adhesiveness, (c) thermal adhesiveness, and conflicting characteristics such as slipperiness and flatness (curl reduction) can be achieved.

(Each configuration and effect)
The heat-adhesive white polyester film of the present invention uses a white biaxially stretched polyester film containing one or both of a white pigment and fine cavities as a base material. Furthermore, it is excellent in environmental suitability (not containing halogen), heat resistance, chemical resistance, and concealment. Further, inclusion of fine cavities in the film also has the effect of imparting lightness, flexibility and cushioning properties to the card. It is preferable from the viewpoint of uneven absorbability to contain a cavity and impart cushioning properties.

  In the present invention, since a thermal adhesive layer containing amorphous polyester resin A as a constituent component is laminated at a specific thickness on at least one surface of the base film, the core sheet of an IC card or IC tag is used. When used, it has excellent thermal adhesiveness and unevenness absorbability.

  The heat-adhesive white polyester film of the present invention has a structure in which the molecular chain is stretched and oriented while the thickness of the heat-adhesive layer is adjusted to a specific range and is an amorphous polyester resin. Therefore, it is possible to improve the thermal deformation of the processed IC card or IC tag to the extent that there is no practical problem.

  Furthermore, in the thermal adhesive layer, a thermoplastic resin B that is incompatible with the amorphous polyester resin A and has a melting point of 50 to 180 ° C. is dispersed in the amorphous polyester resin A in the form of particles. -A moderate unevenness | corrugation is formed in the surface of a heat bonding layer by carrying out biaxial stretching of the heat bonding layer which consists of a resin mixture which has an island structure. And slip property can be improved by controlling the maximum height (St1, Sa1) of the surface of a thermal contact bonding layer to an appropriate range.

  Further, even if the protrusion formed on the surface of the thermal adhesive layer by the thermoplastic resin B having a melting point of 50 to 180 ° C. is a large protrusion, it hardly falls off. Therefore, there is little possibility that the process is contaminated. Further, when each component member is thermally bonded by hot pressing to produce a card or a tag, the protrusion is softened and deformed and flattened even at a low hot pressing temperature (St2). Therefore, the thermal adhesiveness that occurs when adding inorganic / organic particles having a large particle diameter as in the prior art does not deteriorate. In addition, since the degree of freedom of deformation is greater than that of inorganic / organic particles, there is little risk that the strength of the film will decrease.

  Moreover, in the heat-adhesive white polyester film suitable for the present invention, the planarity required when used as a constituent material for an IC card or IC tag can be improved. This is because the thickness of the thermal adhesive layer and the thickness of the base film are adjusted, and the heat shrinkage rate and linear expansion coefficient on the front and back of the film are controlled to an appropriate range, thereby reducing the curl generated in the post-processing step, etc. It is.

  Moreover, in the heat-adhesive white polyester film suitable in the present invention, a number of fine cavities can be contained in the film by a known technique for producing a void-containing polyester film. This is a technique that has been difficult with conventional PVC and PETG sheets. Thereby, the apparent density of the heat-adhesive white polyester film, that is, the void content can be adjusted to an appropriate range.

  Appropriate inclusion of fine cavities in the film is effective for imparting lightness, flexibility, cushioning and writing properties to the IC card or IC tag. Moreover, concealment property can also be provided. An IC card or IC tag using a lightweight void-containing polyester film as a material does not sink immediately even when dropped in water or in the sea. Therefore, in many cases, an accident in which the IC card or IC tag is lost can be avoided.

  The void-containing polyester film has an apparent dielectric constant lower than that of the polyester film or sheet that does not contain voids. Therefore, dielectric loss is small in communication using high frequency in the HF band or SHF band. That is, an IC card or IC tag using a void-containing polyester film as a material has a high gain and is effective in communication accuracy, communication distance, and power saving.

  The heat-adhesive white polyester film of the present invention is based on a white biaxially stretched polyester film containing one or both of a white pigment and fine cavities, and a heat-adhesive layer is laminated on one or both sides of the substrate. A heat-adhesive white polyester film having a thickness of 5 to 30 μm and a glass transition temperature of 50 to 95 ° C. and an incompatible thermoplastic resin. The thermoplastic resin B is a crystalline resin having a melting point of 50 to 180 ° C., and 1 to 30% by mass in the thermal adhesive layer.

  In addition, the method for producing an IC card or IC tag according to the present invention includes the above-described thermal adhesive film disposed on one or both sides of an inlet provided with an antenna circuit and an IC chip on a plastic film, and thermal adhesion of the thermal adhesive film. A core sheet, in which an inlet is hot-pressed and bonded through a layer, is used as a constituent element.

  In addition, the IC card or IC tag of the present invention is formed by laminating the above thermal adhesive film on one or both sides of an inlet provided with an antenna circuit and an IC chip on a plastic film, and through the thermal adhesive layer of the thermal adhesive film. And a core sheet bonded to the inlet as a constituent element. A further preferred embodiment is an IC card or IC tag in which a polyester sheet or a biaxially stretched polyester film is laminated on both surfaces of a core sheet.

  Hereinafter, embodiments of the present invention will be described in detail.

[Composition of film]
It is important that at least one layer of the heat-adhesive white polyester film of the present invention is a biaxially stretched white polyester film containing one or both of a white pigment and fine cavities therein. By including a white pigment or fine cavities, a concealability suitable for use as an IC card can be obtained. The concealment property in the IC card plays an important role in hiding the internal mechanism and preventing malicious destruction or alteration. In addition, the inclusion of fine cavities can make the card lighter, more flexible, and provide cushioning properties that are important for writing, which is a more preferable embodiment.

  Moreover, it is important for the heat-adhesive biaxially stretched white polyester film of the present invention to have a biaxially stretched white polyester film layer as a base material. In addition to environmental suitability that does not contain halogen compounds, this is important in terms of heat resistance, chemical resistance, strength, rigidity, etc., and as a result, it has dramatically improved performance compared to PVC and PETG that have been used in the past. Demonstrate.

  In addition, it is important for the heat-adhesive biaxially stretched white polyester film of the present invention to laminate a biaxially stretched thermal adhesive layer as a sublayer on at least one side of the white polyester film that is the main layer (base material). is there. The thermal adhesive layer here is a layer that can be thermally bonded to a plastic film or sheet, a metal film, and various coating layers formed on the surface of the IC card or IC tag under heating conditions. By laminating this thermal adhesive layer on the substrate, the same thermal adhesiveness as PVC, PETG, etc., which are the materials of conventional IC cards or IC tags can be imparted.

  It is important that the thickness of the thermal adhesive layer is 5 to 30 μm per layer. When the thickness of the thermal adhesive layer is less than 5 μm, the thermal adhesiveness and the unevenness absorbability are insufficient. On the other hand, when the thickness of the thermal adhesive layer exceeds 30 μm, the heat resistance and chemical resistance are lowered as in the case of a card using a conventional PETG sheet as a material. The lower limit of the thickness of the heat bonding layer is preferably 8 μm and more preferably 10 μm. On the other hand, the upper limit of the thickness of the heat bonding layer is preferably 25 μm and more preferably 20 μm.

  The means for providing the thermal adhesive layer on the surface of the base material is not particularly limited, but in order to laminate stably in the above thickness, in the production process of the biaxially stretched polyester film, two types of raw materials are melt-extruded. It is preferable to produce an unstretched sheet using a method of coextruding and laminating a resin, a so-called coextrusion method. Moreover, it is preferable to laminate | stack before a extending process also from a viewpoint of providing moderate heat resistance to a heat bonding layer, and to extend | stretch both a heat bonding layer and a base material (white polyester film layer).

  In the heat-adhesive white polyester film of the present invention, providing a heat-adhesive layer on both surfaces of the substrate is a preferred embodiment from the viewpoint of suppressing curling of the film. In the present invention, the thermal adhesive layer is mainly composed of an amorphous resin, and the thermal expansion coefficient is greatly different from that of a base material mainly composed of a crystalline polyester resin. For this reason, when a thermal adhesive layer is provided only on one side of the substrate, it may curl like a bimetal depending on processing conditions and use conditions, and there is a concern about poor flatness and handling properties. When providing a heat bonding layer on both surfaces of a base material, it is preferable that the thickness ratio of the heat bonding layer of the front and back is 0.5-2.0. When it is out of this range, curling may occur due to the above reason. Even when curling occurs, if the curl value after heat treatment at 110 ° C. for 30 minutes in a no-load state is 5 mm or less, there is no substantial hindrance to handling properties. More preferably, the curl value is 3 mm or less, and particularly preferably 1 mm or less.

  As another method for suppressing curling, there is a method in which the temperature and heat quantity given to the front and back surfaces of the film are positively differentiated, and as a result, the curl value is brought close to zero. Specifically, in the stretching process such as longitudinal stretching and lateral stretching, and the heat setting process, the degree of orientation of the front and back surfaces of the film is controlled independently by setting the temperature or the amount of heat on the front and back of the film to different values. Balance the structure and physical properties of the front and back surfaces. As a result, curling can be reduced. When this method is used, in the heating / cooling process of the step of longitudinally stretching the film, it is easy to adjust the temperature of the roll or infrared heater for heating the front and back surfaces of the film, which is a preferable method.

  Moreover, it is preferable that the thickness of the whole film of the heat-adhesive white polyester film of this invention is 50-350 micrometers. The lower limit of the thickness of the entire film is more preferably 70 μm and even more preferably 90 μm. On the other hand, the upper limit of the thickness of the entire film is more preferably 280 μm, further preferably 200 μm. When the thickness of the entire film is less than 50 μm, the thickness is not sufficient as a base material for an IC card or an IC tag, and does not contribute to improvement of heat resistance of the entire card. On the other hand, when the thickness of the whole film exceeds 350 μm, combinations with other sheets, films, and electric circuits are limited in the standard thickness of the card (the card in the JIS standard is 0.76 mm).

  In addition, in the heat-adhesive white polyester film of the present invention, a coating layer is provided on the surface of the film in order to further improve the heat-adhesion property and slip property, or to provide other functions such as antistatic properties. Is also possible.

  For example, in order to improve adhesiveness, it is preferable to use a polyester resin, a polyurethane resin, a polyester urethane resin, an acrylic resin, or the like as the adhesive modification resin as the resin constituting the coating layer. As a guideline for selecting a preferable one among these adhesiveness-modified resins, it is preferable that a high affinity is applied to the surface to be bonded by applying the present invention, and a compound having a similar surface tension and solubility parameter is selected. It is preferable. However, when a curable resin is applied thickly, the unevenness absorbability, which is one of the objects of the present invention, may be lowered, so care must be taken. In order to improve antistatic properties, known antistatic agents can be applied, and among them, polymer-based antistatic is preferable.

  As a method for providing the coating layer, conventionally used methods such as a gravure coating method, a kiss coating method, a dip method, a spray coating method, a curtain coating method, an air knife coating method, a blade coating method, and a reverse roll coating method can be applied. As a step of applying, any method such as a method of applying before stretching of the film, a method of applying after longitudinal stretching, and a method of applying to the film surface after the orientation treatment is possible.

[Thermal adhesive layer]
In the heat-adhesive white polyester film of the present invention, it is important that the heat-adhesive layer contains the amorphous polyester resin A as a main component.

  The amorphous polyester resin A here is a polyester resin having a heat of fusion of 20 mJ / mg or less. The heat of fusion is measured by heating at a rate of 10 ° C./min in a nitrogen atmosphere using a DSC apparatus in accordance with “Method for measuring the transition heat of plastic” described in JIS-K7122. In the present invention, the heat of fusion is preferably 10 mJ / mg or less, more preferably no melting peak is observed. When the amount of heat of fusion exceeds 20 mJ / mg, the thermal adhesive layer is hardly deformed, and the unevenness absorbability cannot be sufficiently obtained.

  Further, it is important that the amorphous polyester resin A has a glass transition temperature of 50 ° C. or more and 95 ° C. or less. The glass transition temperature was obtained by heating at a rate of 10 ° C./min in a nitrogen atmosphere using a DSC apparatus according to “Method for measuring plastic transition temperature” described in JIS-K7121. It means the midpoint glass transition temperature (Tmg) determined based on the curve. The lower limit of the glass transition temperature of the amorphous polyester resin A is preferably 60 ° C and more preferably 70 ° C. On the other hand, the upper limit of the glass transition temperature is preferably 90 ° C, more preferably 85 ° C. When the glass transition temperature is less than 50 ° C., it is deformed due to insufficient heat resistance when used as an IC card or IC tag, or the thermal adhesive layer is peeled off by slight heating. On the other hand, when the glass transition temperature exceeds 95 ° C., it is necessary to heat the IC card or the IC tag at a higher temperature, which increases the burden on the electric circuit.

  The type of the amorphous polyester resin A is not particularly limited, but from the viewpoint of versatility, cost, durability, and thermal adhesiveness to a PETG sheet, various types of copolymer are used in the molecular skeleton of the aromatic polyester resin represented by polyethylene terephthalate. What introduce | transduced the polymerization component is used preferably. Among the copolymer components to be introduced, examples of the glycol component include ethylene glycol, diethylene glycol, neopentyl glycol (NPG), cyclohexanedimethanol (CHDM), propanediol, and butanediol. On the other hand, examples of the acid component include terephthalic acid, isophthalic acid, and naphthalenedicarboxylic acid. As the copolymer component, a monomer that can lower the glass transition temperature and improve the thermal adhesiveness at a low temperature is selected. Examples of such a polymerization component include a glycol having a long linear component or a non-linear structure component having a large steric hindrance. The latter component is used when it is desired to improve the unevenness absorbability by effectively reducing the crystallinity of the thermal adhesive layer. In the present invention, from the viewpoint of thermal adhesiveness to the PETG sheet, CHDM and NPG are preferable, and NPG is more preferable.

  In addition, as the amorphous polyester resin A, there are some which are generally developed for adhesive use and are commercially available. When such an adhesive resin is used, since it was originally developed as an adhesive, there is a possibility that it can be bonded to a wide range of materials. However, it may be difficult for such an adhesive resin to be stably coextruded in the production process of a biaxially stretched film. In such a case, it is necessary to sufficiently adjust the temperature of the extruder and the thickness of the thermal adhesive layer.

  In addition to the amorphous polyester resin A, a thermoplastic resin B having a melting point of 50 to 200 ° C. that is incompatible with the amorphous polyester resin A is mixed in the heat-adhesive layer of the heat-adhesive biaxially stretched white polyester film of the present invention. And use.

  Thermoplastic resin B having a melting point of 50 to 200 ° C. is observed when heating at 10 ° C./min in a nitrogen atmosphere by a DSC apparatus according to “Method for measuring plastic transition temperature” described in JIS K 7121. It means a resin having a melting point of 50 ° C. or higher and 200 ° C. or lower. This thermoplastic resin B forms a sea-island structure in the amorphous polyester resin A, and protrusions resulting from this are formed on the surface of the thermal adhesive layer. This protrusion plays a role of maintaining the hardness at room temperature and improving the slipperiness of the film. Therefore, the lower limit of the melting point of the resin B is more preferably 70 ° C, and further preferably 90 ° C.

  On the other hand, in the thermal bonding process, this protrusion is crushed and flattened, and also plays a role of not inhibiting the adhesiveness. Therefore, it is not preferable that the melting point of the resin B exceeds 30 ° C. more than the maximum temperature in the thermal bonding process. More specifically, the melting point of the resin B is more preferably 160 ° C. or less.

In the present invention, the kind of the thermoplastic resin B is not particularly limited. However, since the thermoplastic resin B is mixed with the amorphous polyester resin A in the thermal adhesive layer, the solubility parameter of the resin B is 2.0 compared to polyethylene terephthalate. (J / cm ³ ) A resin larger than ^1/2 or smaller is preferable.

Examples of the crystalline and highly versatile resin suitable as the resin B include polyethylene, polypropylene, polybutadiene, polyethylene propylene rubber, polylactic acid, and polyoxymethylene. Among these, polyethylene or polypropylene is preferable because it has high stability to heat, ultraviolet rays, and oxygen and is more versatile. In addition, polyethylene is more preferable because the melting point is appropriate. The polyethylene is preferably high-density polyethylene or linear low-density polyethylene having a density exceeding 0.90 g / cm ³ from the viewpoint of crystallinity.

  Moreover, in this invention, the quantity of the thermoplastic resin B contained in a thermobonding layer is 1-30 mass% with respect to the material which comprises a thermobonding layer. 3 mass% is preferable and, as for the minimum of content of the thermoplastic resin B, 5 mass% is more preferable. On the other hand, the upper limit of the content of the thermoplastic resin B is preferably 25% by mass, and more preferably 20% by mass. When the content of the thermoplastic resin B is less than 1% by mass, the required slip property cannot be obtained. On the other hand, when the content of the thermoplastic resin B exceeds 30% by mass, it becomes a coarse protrusion and falls off the surface of the film, conversely, the slipperiness is deteriorated, or heat bonding without sufficiently flattening with a hot press. Sexuality gets worse.

  Moreover, in this invention, it is preferable that the maximum height (St1) of the surface of a heat bonding layer is 1.0-10 micrometers. The lower limit of the maximum height of the surface of the thermal adhesive layer is more preferably 1.2 μm, and particularly preferably 1.5 μm. On the other hand, the upper limit of the maximum height of the surface of the heat bonding layer is more preferably 8.0 μm, and particularly preferably 5.0 μm. When the maximum height of the surface of the heat bonding layer is less than 1.0 μm, sufficient slipperiness cannot be obtained, and handling of the film becomes difficult. On the other hand, when the maximum height of the surface of the thermal adhesive layer exceeds 10 μm, the protrusions on the surface of the film fall off due to rubbing to contaminate the process, or on the contrary, the slipperiness becomes worse.

  In the present invention, the ratio (St1 / Sa1) between the maximum surface height (St1) and the arithmetic average surface roughness (Sa1) of the thermal bonding layer is 3.0 or more and 20 or less. preferable. The lower limit of St1 / Sa1 is more preferably 5.0, and particularly preferably 7.0. On the other hand, the upper limit of St1 / Sa1 is more preferably 16, and particularly preferably 12. When St1 / Sa1 is less than 3.0, it becomes difficult to improve slipperiness. On the other hand, when St1 / Sa1 exceeds 20, it becomes difficult to obtain thermal adhesiveness.

  As a method of adjusting the maximum height (St1) of projections on the surface of the thermal adhesive layer and the arithmetic average surface roughness (Sa1) to appropriate ranges, (1) melt viscosity and glass transition temperature of the amorphous polyester resin A (2) Method of adjusting the melt viscosity, glass transition temperature, melting point, surface tension, solubility parameter, addition amount of thermoplastic resin B, (3) When extruding the resin of the thermal adhesive layer onto the film surface The method of adjusting the temperature of the is mentioned. Among these methods, the method of adjusting the glass transition temperature of the amorphous polyester resin A, the type and addition amount of the thermoplastic resin, and the extrusion temperature is easy and reliable.

  Further, in the present invention, the maximum protrusion height on the surface of the heat bonding layer after the surface of the heat bonding layer is sandwiched between a smooth and clean glass plate and subjected to hot press treatment (100 ° C., 1 MPa, 1 minute). The thickness (St2) is preferably 0.001 μm or more and 3.000 μm or less.

  The lower limit of St2 is more preferably 0.005 μm, and most preferably 0.01 μm. The upper limit of St2 is more preferably 2.500 μm, and most preferably 2.000 μm or less. When St2 is less than 0.005 μm, the resin constituting the thermal adhesive layer flows during hot pressing, and the processing stability may be insufficient. Further, when St2 exceeds 0.01 μm, many protrusions remain even after hot pressing, and an adhesive interface sufficient to exhibit a stable adhesive force cannot be obtained, which is not preferable. In order to adjust St2 within the range of 0.001 to 3.00 μm, the melting point of the crystalline thermoplastic resin is adjusted within the range of 50 to 200 ° C., or the content of the crystalline thermoplastic resin is set to 1 It is effective to adjust within the range of ˜30% by mass.

  Moreover, in the heat-adhesive white polyester film of this invention, it is preferable that the surface and back surface of a film are made to oppose, and the static friction coefficient in the interface is 0.1 or more and 0.8 or less. The lower limit of the friction coefficient is more preferably 0.2. On the other hand, the upper limit of the friction coefficient is more preferably 0.7, still more preferably 0.6, and particularly preferably 0.5. It is difficult within the scope of the present invention to make the coefficient of static friction between the front and back surfaces of the film less than 0.1. On the other hand, when the static friction coefficient exceeds 0.8, the handling property of the film is remarkably deteriorated. In order to adjust the static friction coefficient within the range of 0.1 to 0.8, as described above, the maximum height of the surface of the thermal adhesive layer is adjusted, and the elastic modulus and surface tension of the thermal adhesive layer are adjusted. It is preferable to adjust.

  Further, in the heat-adhesive white polyester film of the present invention, it is one of preferred embodiments to contain a white pigment in the heat-adhesive layer as long as the heat-adhesiveness, slipperiness, and unevenness absorbability are not impaired. As the white pigment to be contained in the thermal adhesive layer, those composed of titanium oxide, calcium carbonate, barium sulfate and a composite thereof are preferable. Among these, titanium oxide is more preferable from the viewpoint of the concealment effect. These inorganic particles are preferably contained in a range of 30% by mass or less, more preferably 20% by mass or less, with respect to the constituent material of the biaxially stretched polyester film of the substrate. When it exceeds the above range, the above properties may be inhibited.

  In the heat-adhesive white polyester film of the present invention, organic particles may be contained in the heat-adhesive layer as long as the heat-adhesiveness, slipperiness, and unevenness absorbability are not impaired. By including organic particles in the heat bonding layer, it is possible to form protrusions on the surface of the heat bonding layer. It becomes possible to discharge. As the organic particles, melamine resin, cross-linked polystyrene resin, cross-linked acrylic resin and composite particles mainly composed of these are preferable. In addition, it is preferable to contain these inorganic particles in 30 mass% or less with respect to the constituent material of a heat bonding layer, and it is more preferable to set it as 20 mass% or less. When it exceeds the above range, the above properties may be inhibited.

[White biaxially stretched polyester film layer (base film)]
The heat-adhesive white polyester film of the present invention has an apparent density of 0.7 g / cm ^{3 to} 1.3 g / cm ³ , an optical density of 0.5 to 3.0, and a thickness of 50 μm to 350 μm. Preferably there is.

  The optical density of the adhesive white polyester film is adjusted to a range of 0.5 to 3.0 by appropriately adjusting the amount of fine cavities inside the film and the amount of white pigment added. The lower limit of the optical density is more preferably 0.7, further preferably 0.9. On the other hand, the upper limit of the optical density is more preferably 2.5, and further preferably 2.0.

  By using the heat-adhesive white polyester film having the above optical density range as a constituent material of a core sheet used for an IC card or IC tag, the light transmittance of the IC card or IC tag is in the range of 0.01 to 5%. Can be adjusted.

  If the optical density of the heat-adhesive white polyester film is less than 0.5, when an IC card or IC tag is used, internal structures such as IC chips and electrical circuits may be seen through due to insufficient concealment. In terms of design and safety, it is not preferable. On the other hand, in order to produce the optical density of the heat-adhesive white polyester film to exceed 3.0, it is necessary to contain a large amount of fine cavities and white pigments inside the film, There is a tendency for breakage during film production to occur frequently.

  In order to adjust the optical density of the heat-adhesive white polyester film to 0.5 to 3.0, (1) a thermoplastic resin that is incompatible with the polyester resin is used as the white biaxially stretched polyester film as the base material. A method of biaxially stretching the mixed resin composition to form a cavity, (2) a method of biaxially stretching a resin composition containing a white pigment in a polyester resin, and (3) a method of using both in combination. Either method is used.

  In the method of incorporating a white pigment in the film, it is preferable to use titanium oxide, calcium carbonate, barium sulfate and a composite thereof as the white pigment. Among these, titanium oxide is particularly preferable from the viewpoint of concealability. The content of these white pigments is preferably 25% by mass or less, more preferably 20% by mass or less, with respect to the constituent material of the white polyester layer of the substrate. When the content of the white pigment in the film exceeds 25% by mass, the frequency of breaking during film production increases, and it may be difficult to produce stably at an industrial level.

On the other hand, it is also a preferred embodiment to use a void-containing polyester film containing a large number of fine voids therein as the base film. The apparent density of the film can be controlled to 0.7 to 1.2 g / cm ³ by a large number of fine cavities inside the film. The lower limit of the apparent density of the film is more preferably 0.8 g / cm ^3, more preferably 0.9 g / cm ^3. On the other hand, the upper limit of the apparent density of the film is more preferably 1.2 g / cm ³ , and particularly preferably 1.1 g / cm ³ . If the apparent density of the film is less than 0.7 g / cm ³ , the strength, buckling resistance, and compression recovery rate of the film will decrease, and appropriate performance will be obtained in the processing and use of IC cards or IC tags. It becomes difficult. On the other hand, when the apparent density of the film exceeds 1.2 g / cm ³ , it is difficult to obtain lightness and flexibility as an IC card or IC tag.

  As a method for containing cavities inside the film, (a) a method in which a foaming agent is contained and foamed by heat during extrusion or film formation, or foamed by chemical decomposition, (b) carbon dioxide gas during or after extrusion (C) A method in which a gas or vaporizable substance such as is added and foamed, (c) A method in which a polyester and an incompatible thermoplastic resin are added to the polyester, and after melt extrusion, the film is stretched uniaxially or biaxially. ) A method of stretching uniaxially or biaxially after adding organic or inorganic fine particles and melt-extruding can be mentioned.

  Among the methods for incorporating cavities in the film, the method (c), that is, a method in which a thermoplastic resin that is incompatible with polyester is added, and after melt extrusion, is stretched uniaxially or biaxially is preferable. . The thermoplastic resin incompatible with the polyester resin is not limited in any way, but is a polyolefin resin represented by polypropylene or polymethylpentene, a polystyrene resin, a polyacrylic resin, a polycarbonate resin, or a polysulfone resin. Examples thereof include cellulose resins and polyphenylene ether resins.

  These thermoplastic resins may be used alone or in combination of a plurality of thermoplastic resins. The content of the thermoplastic resin incompatible with these polyester resins is preferably 3 to 20% by mass, more preferably 5 to 15% by mass with respect to the resin forming the void-containing polyester layer. And, if the content of the thermoplastic resin incompatible with the polyester resin is less than 3% by mass with respect to the resin forming the void-containing polyester layer, the void content formed inside the film is reduced, so that the concealing property is reduced. descend. On the other hand, when the content of the incompatible thermoplastic resin exceeds 20% by mass with respect to the resin forming the white polyester layer (base material), the frequency of breaking in the film manufacturing process increases. The void content inside the void-containing polyester film is preferably 10 to 50% by volume, and more preferably 20 to 40% by volume.

  In addition, the white biaxially stretched polyester film as the base material includes a method of forming a cavity by biaxially stretching a resin composition in which a thermoplastic resin that is incompatible with the polyester resin is mixed, and a white pigment in the polyester resin. A method in which a resin composition containing a biaxially stretched resin composition is used in combination is most preferable.

  In the heat-adhesive white polyester film of the present invention, each layer except the heat-adhesive layer is preferably composed mainly of crystalline polyester. The crystalline polyester resin here is a polyester resin having a heat of fusion exceeding 20 mJ / mg. The method for measuring the heat of fusion is the same as described above.

  Such crystalline polyesters include aromatic dicarboxylic acids or their esters such as terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, and ethylene glycol, diethylene glycol, 1,3-propanediol, 1,4-butanediol, neopentyl glycol, etc. Polyester produced by polycondensation with an appropriate amount of glycol. In addition to the direct weight method in which an aromatic dicarboxylic acid and a glycol are directly reacted, these polyesters can be transesterified by an alkyl ester of an aromatic dicarboxylic acid and a glycol and then subjected to a polycondensation, or an aromatic method. It can be produced by a method such as polycondensation of diglycol ester of dicarboxylic acid.

  Representative examples of the crystalline polyester include polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, and polyethylene-2,6-naphthalate. The polyester may be a homopolymer or a copolymer of a third component. Among these polyesters, a polyester having an ethylene terephthalate unit, a trimethylene terephthalate unit, or an ethylene-2,6-naphthalate unit of 70 mol% or more, preferably 80 mol% or more, more preferably 90 mol% or more is preferable. .

[IC card or IC tag and manufacturing method thereof]
The IC card or the IC tag of the present invention has the above-mentioned heat-adhesive film disposed on one or both sides of an inlet provided with an antenna circuit and an IC chip on a plastic film, and the inlet via the heat-adhesive layer of the heat-adhesive film. It can be manufactured by using a core sheet bonded by hot pressing as a constituent element. Further, a more preferable manufacturing method of the IC card or IC tag is to laminate a polyester sheet (for example, non-oriented PETG sheet) or a biaxially stretched polyester film on both sides of the core sheet, and then hot press, In this method, the respective members are bonded and integrated.

  In addition, an inlet shows the product form until the state which mounted the IC chip in the antenna circuit or the metal coil, and consists of the structure which provided the antenna circuit and the IC chip on the single side | surface of the plastic film. The product form is the most basic, and the antenna circuit, the metal coil, and the IC chip are exposed.

  Usually, when a card is constituted with a biaxially stretched polyester film as a core material, the use of an adhesive such as a hot melt sheet is indispensable, but this is not necessary in the heat-adhesive white polyester film of the present invention, and the card or tag Production efficiency can be improved and manufacturing costs can be reduced.

  In addition, the IC card or IC tag of the present invention is formed by laminating the above thermal adhesive film on one or both sides of an inlet provided with an antenna circuit and an IC chip on a plastic film, and through the thermal adhesive layer of the thermal adhesive film. And a core sheet bonded to the inlet as a constituent element. A further preferred embodiment is an IC card or IC tag in which a polyester sheet or a biaxially stretched polyester film is laminated on both surfaces of a core sheet.

  The card and tag indicate the shape and use of the article. If the card or tag includes an inlet in which an antenna circuit or a metal coil and an IC chip are provided on a plastic film, the form and use of the IC card or IC tag can be reduced. Different ones are also encompassed by the present invention.

  Since the heat-adhesive white polyester film of the present invention has a heat-adhesive layer made of amorphous polyester on one or both sides, it can be bonded to known polyester sheets and polyester films without using an adhesive. It is. The polyester sheet is not particularly limited, but it is preferable to use a low crystalline or amorphous polyester sheet obtained by copolymerizing a component such as isophthalic acid, cyclohexanedimethanol, or neopentyl glycol with polyethylene terephthalate. Moreover, when using a biaxially stretched polyester film, the kind is not specifically limited, However, It is preferable to use the white polyester film suitable for a card | curd or a tag, or a void containing polyester film. Furthermore, it is a further preferred embodiment to use a biaxially stretched polyester film in which a surface treatment layer with improved printability and adhesiveness is formed.

  Moreover, when manufacturing an IC card or an IC tag according to the present invention, the inlet having an antenna circuit or an IC chip is preferably disposed adjacent to at least one surface of the heat-adhesive white polyester film of the present invention. The thermal adhesive layer of the present invention can be easily deformed in a hot press process, and can effectively relieve irregularities caused by circuits and chips. It is possible to manufacture.

  In this invention, when manufacturing a card | curd and a tag with a hot press adhesion method, 90-160 degreeC is preferable and the temperature at the time of a hot press has more preferable 110-150 degreeC. When the temperature at the time of hot pressing is less than 90 ° C., sufficient adhesive force cannot be obtained. On the other hand, when the temperature at the time of hot pressing exceeds 160 ° C., the film is remarkably heat-shrinked so that the shape of the card is not beautiful, which is not preferable in terms of design.

  Moreover, 0.1-20 MPa is preferable and the pressure at the time of a hot press has more preferable 0.3-10 MPa. When the pressure during hot pressing is less than 0.1 MPa, the flatness of the card is not sufficient, and a beautiful appearance cannot be obtained. On the other hand, when the pressure at the time of hot press exceeds 20 MPa, even if a heat-adhesive white polyester film based on a void-containing polyester film is used, its excellent cushioning and unevenness absorption effects are reduced by high pressure. Become. As a result, a burden on a circuit such as an IC chip becomes excessive, and an electrical failure is likely to occur.

One of the preferred embodiments of the IC card or IC tag of the present invention is a heat-adhesive white polyester film (with an apparent density of 0.7 to 0.7) based on a cavity-containing film containing a large number of fine cavities inside the film. 1.3 g / cm ³ ) with an apparent density of 0.7 g / cm ³ or more and less than 1.3 g / cm ³ . The lower limit of the apparent density of the card or tag is more preferably ^{0.8g / cm 3, 0.9g / cm} 3 is more preferred.

The upper limit of the apparent density of the card or tag is more preferably ^{1.2g / cm 3, 1.1g / cm} 3 is more preferred. If the apparent density of the card or tag is less than 0.7 g / cm ³ , the card, tag strength, buckling resistance, and compression recovery rate will decrease, and appropriate mechanical performance will be obtained during processing and use. Disappear. On the other hand, if the apparent density of the card or tag is 1.3 g / cm ³ or more, it is not obtained lightness and flexibility as IC card or IC tag. In addition, an IC card or IC tag with an apparent density of 0.7 g / cm ³ or more and less than 1.3 g / cm ³ is sufficient to float on the water surface in the event of a submergence or to be recovered before sinking. You can get time. For this reason, the card of this embodiment is suitable as a personal information recording card that an individual records the information and uses on a daily basis.

  Next, the relationship between the technical requirements and effects of the present invention will be described in detail with reference to Examples and Comparative Examples. In addition, the characteristic value used by this invention was evaluated using the following method.

[Evaluation methods]
(1) Melting point of resin and glass transition temperature DSC measurement was carried out according to "Method for measuring plastic transition temperature" described in JIS K7121. As the sample, about 10 mg of a small piece obtained by cutting a thermal adhesive layer from a film using a microtome with a magnifying glass, sealed in an aluminum pan, melted at 300 ° C. for 3 minutes, and quenched with liquid nitrogen was used. A differential scanning calorimeter (manufactured by Seiko Instruments Inc., EXSTAR 6200DSC) was used as a measuring instrument, and the measurement was performed under a dry nitrogen atmosphere. After heating from room temperature at a rate of 10 ° C./min to determine the midpoint glass transition temperature, the melting peak temperature (melting point) was determined.

(2) Heat of fusion of resin The amount of heat of fusion was determined according to “Method for measuring heat of transition of plastic” described in JIS K7122. The details of the DSC measurement were the same as those of the above melting point measurement.

(3) Film thickness Measured according to “Foamed plastic-film and sheet-thickness measuring method” described in JIS K 7130. The measuring instrument used was an electronic micrometer (manufactured by Marl, Millitron 1240). Four 5 cm square samples were cut from arbitrary four locations of the film to be measured, and 5 points (20 points in total) were measured per sheet, and the average value was taken as the thickness.

(4) Lamination thickness of film Small pieces were cut out from arbitrary three locations of the film to be measured. The small piece was cut using a microtome to create a film cross section perpendicular to the film surface. A platinum-palladium alloy was sputtered onto the cross section to obtain a sample, and the cross section was examined using a scanning electron microscope (S2500, manufactured by Hitachi, Ltd.). The total thickness of the film was observed at an appropriate magnification included in one field of view, and the thickness of each layer was measured. The measurement was performed at three places for each field of view, and the average value of a total of nine places was used as the laminate thickness.

(5) Surface roughness of the film A small piece was cut out from any three locations of the film to be measured, and dust and the like were carefully removed with a static elimination blower. The surface of the thermal adhesive layer was measured with a non-contact type three-dimensional shape measuring device (Micromap 557, manufactured by Micromap). The optical system used was a mirro-type two-beam interference objective lens (10 times) and a zoom lens (Body Tube, 0.5 times), and received light with a 2/3 inch CCD camera using a light source of 5600 angstroms. The measurement was performed in the WAVE mode, and a 1619 μm × 1232 μm field of view was processed as a digital image of 640 × 480 pixels. For analysis of the image, gradient removal (Detrending) was performed in the linear function mode using analysis software (Micromap 123, version 4.0). Thus, the arithmetic average surface roughness of 5 visual fields (total of 30 visual fields) for each of the three samples was measured, and the average value was defined as the surface roughness (Sa).

(6) Surface roughness of the film after the hot press treatment A smooth and clean glass plate (a slide glass with Sa of 0.0008 μm) was placed on both sides of the part to be observed, and cushioning material (made by Toyobo, manufactured by Toyobo Co., Ltd.) Containing polyester film K1212, 188 μm). This was preheated at 100 ° C. for 5 minutes and then hot pressed (1 MPa, 1 minute). Otherwise, the surface roughness of the film after the hot press treatment was measured in the same manner as the surface roughness of the film.

(7) Coefficient of Static Friction of Film Measured according to “Testing method for foamed plastic film and sheet—friction coefficient” described in JIS K 7125. A tensile tester (manufactured by Shimadzu Corporation, AG1KNI) was used as a measuring instrument. Ten samples were cut from any five locations of the film to be measured, and the measurement was performed with the front and back surfaces of the film facing each other. The load applied to the sliding piece was 1500 g, and the average value of 5 times in total was taken as the coefficient of static friction.

(8) Apparent density of film Five 100 mm square samples cut out from five arbitrary locations were measured by “Measurement of foamed plastic and rubber-apparent density” described in JIS K7222. The measurement was performed at room temperature, and the average value was used as the apparent density. In order to simplify the notation, the unit was converted to g / cm ³ .

(9) Optical density of film The optical density in white light was measured using a transmission type optical densitometer (Macbeth, RD-914). Measurement was performed on five 50 mm square samples cut out from five arbitrary positions of the sample to be measured, and the average value was converted into light transmittance (%).

(10) Curling value of the film The film to be measured was cut into a sheet of 100 mm in the longitudinal direction and 50 mm in the width direction from arbitrary three locations, and after heat treatment at 110 ° C. for 30 minutes in an unloaded state, Standing on a horizontal glass plate with the convex part down, the vertical distance between the glass plate and the lower end of the four corners of the rising film was measured with a ruler in units of a minimum scale of 0.5 mm. The average value of the measured values was taken as the curl value. Three sheets were measured and the average value was taken as the curl value.

(11) Concavity and convexity absorbability A three-dimensional shape measuring device (Ryoka System Co., Ltd., Micromap TYPE550, objective lens 10 times) is used for the outer edge of the part where the antenna circuit or the copper foil is arranged with the created IC card or IC tag. And observed in WAVE mode. Three visual fields (three locations per visual field) were observed for the level difference caused by the presence or absence of the antenna circuit or copper foil, and the average value was obtained. The smaller the step, the better the unevenness absorbability, and the case where the step was less than 3 μm was marked as “◎”, the case where it was 3 μm or more and less than 6 μm, and the case where it was 6 μm or more. In addition, when copper foil is used, there is no function as an IC card or IC tag, but it can be used as a model evaluation method for unevenness absorption when a card or tag is prepared using a heat adhesive film.

(12) Thermal adhesiveness of film The prepared IC card or IC tag was peeled off manually. The case where no thermal bonding was performed was rated as “X”, the case where interfacial debonding was entirely performed was indicated as “Δ”, the case where the thermal bonding layer was largely agglomerated and broken, and the case where material was broken was marked as “A”.

(13) Heat resistance of IC card or IC tag The prepared IC card or IC tag is allowed to stand on a clean and flat stainless steel plate (SUS304, thickness 0.8 mm), and 120 ° C in an air atmosphere using an oven. For 24 hours. Visually evaluate the appearance of samples before and after heating (loss of gloss, discoloration, cloudiness, cracks, deformation, melting, fusion), ○ if there is no difference between before and after heating, △ depending on the degree Or it was set as x.

(14) Intrinsic Viscosity of Polyester Resin According to "Plastics-Determination of viscosity of polymer diluted solution using capillary viscometer-" described in JIS K 7367-5, phenol / 1,1,2,2-tetrachloroethane It measured at 30 degreeC using the mixed solvent of (60/40; mass part).

(15) Average particle diameter of particles The particles were observed with a scanning electron microscope (S2500, manufactured by Hitachi, Ltd.), the magnification was appropriately changed according to the size of the particles, and the photographed image was enlarged and copied. Next, the circumference of each particle was traced for at least 200 particles randomly selected. The equivalent circle diameters of the particles were measured from these trace images with an image analyzer, and the average value thereof was taken as the average particle diameter.

<Manufacture of film raw materials>
[Manufacture of polyethylene terephthalate resin]
When the temperature of the esterification reactor was raised to 200 ° C., a slurry composed of terephthalic acid [86.4 parts by mass] and ethylene glycol [64.4 parts by mass] was charged and stirred as trioxide as a catalyst. Antimony [0.017 parts by mass] and triethylamine [0.16 parts by mass] were added. Next, the temperature was raised by heating, and a pressure esterification reaction was carried out under conditions of a gauge pressure of 0.34 MPa and 240 ° C.

  Thereafter, the inside of the esterification reaction vessel was returned to normal pressure, and magnesium acetate tetrahydrate [0.071 parts by mass] and then trimethyl phosphate [0.014 parts by mass] were added. Furthermore, after heating up to 260 degreeC over 15 minutes, trimethyl phosphate [0.012 mass part] and then sodium acetate [0.0036 mass part] were added. The obtained esterification reaction product was transferred to a polycondensation reaction can, gradually heated from 260 ° C. to 280 ° C. under reduced pressure, and then subjected to a polycondensation reaction at 285 ° C. After the polycondensation reaction, filtration was performed with a stainless steel sintered filter having a pore size of 5 μm (initial filtration efficiency: 95%).

  Next, polyethylene terephthalate (PET), which is the polycondensation reaction product, was pelletized in a sealed chamber in which foreign matters having a diameter of 1 μm or more existing in the air were reduced with a hepa filter. Pelletization was performed by a method of extruding molten PET into a cooling water tank from a nozzle of an extruder and cutting the formed strand-like PET resin while flowing cooling water that had been previously filtered (pore size: 1 μm or less). . The obtained PET pellets have an intrinsic viscosity of 0.62 dl / g, an Sb content of 144 ppm, an Mg content of 58 ppm, a P content of 40 ppm, a color L value of 56.2, and a color b value of 1.6. Inert particles and internally precipitated particles were not substantially contained.

[Production of Amorphous Polyester Resin A]
In the production of the PET resin, 20 mol% of the glycol component was changed from ethylene glycol to neopentyl glycol, and thus an amorphous polyester resin A1 was obtained. Analysis of this resin by DSC apparatus showed no melting point and a glass transition temperature of 78 ° C.
In the production of the PET resin, 30 mol% of the glycol component was changed from ethylene glycol to cyclohexanedimethanol to obtain amorphous polyester resin A2. Analysis of this resin by DSC apparatus showed no melting point and a glass transition temperature of 81 ° C.

[Preparation of cavity forming agent-containing master pellets]
Polystyrene resin having a melt flow rate of 1.5 (Nihon Polystyrene G797N, manufactured by Nippon Polystyrene Co., Ltd.) [20% by mass], vapor-phase polymerization polypropylene resin having a melt flow rate of 3.0 (IDEMITSU PP F300SP, manufactured by Idemitsu Petrochemical Co., Ltd.) [ 20 mass%] and a polymethylpentene resin having a melt flow rate of 180 (Mitsui Chemical Co., Ltd., TPX DX-820) [60 mass%] are mixed in pellets, supplied to a twin-screw extruder, kneaded sufficiently, and strands. Was cooled and cut to prepare a master pellet containing a cavity forming agent.

[Preparation of titanium oxide-containing master pellets]
Vented biaxial mixture of 50% by mass of the polyethylene terephthalate resin obtained above and anatase-type titanium dioxide (TA-300, manufactured by Fuji Titanium) [50% by mass] having an average particle size of 0.3 μm (SEM method) After being supplied to an extruder and pre-kneaded, the molten polymer was continuously supplied to a vent type single-screw kneader and kneaded to prepare titanium oxide-containing master pellets.

[Preparation of organic particle-containing master pellets]
Vent-type twin screw extrusion obtained by mixing 70% by mass of the polyethylene terephthalate resin obtained above with melamine particles having an average particle size of 3.5 μm (catalog value) (Opto Beads 3500M, manufactured by Nissan Chemical Industries, Ltd.) [30% by mass] After being supplied to the machine and pre-kneaded, the molten polymer was continuously supplied to the bent type single-screw kneader and kneaded to prepare organic particle-containing master pellets.

Example 1
A mixture of the cavity forming agent-containing master pellet [8 mass%], the titanium oxide-containing master pellet [6 mass%], and the PET resin [86 mass%] was used as a raw material M. Further, the amorphous polyester resin A1 [90% by mass] and a linear low density polyethylene resin (Ube Industries, Ltd., Umerit 2040F; melting point 116 ° C., density as the thermoplastic resin B incompatible with the resin A1. 0.918 g / cm ³ ) [10% by mass] was used as the raw material C. These raw material M and raw material C were vacuum-dried to a moisture content of 80 ppm and supplied to separate extruders. At the time of extrusion, in order to adjust the mixing property and lamination stability, the raw material M is heated to 280 ° C. inside the extruder, melted and mixed, and then led to the feed block at a resin temperature of 270 ° C. The mixture was melted and mixed up to 250 ° C. and then led to a feed block at a resin temperature of 280 ° C. This was joined with a feed block so that the thermal bonding layer made of the raw material C was laminated on both surfaces of the intermediate layer made of the raw material M. This was extruded from a T-shaped die onto a cooling drum adjusted to 20 ° C. to produce a three-layer unstretched film having a thickness of 1.9 mm. During the production of the unstretched film, the opposite surface of the cooling drum was cooled by blowing cold air adjusted to 20 ° C. and a relative humidity of 30%.

  The obtained unstretched film was uniformly heated to 65 ° C. using a Teflon (registered trademark) heating roll, and further provided with a gold reflective film having a surface temperature of 700 ° C. disposed opposite to both surfaces of the film. The film was stretched 3.4 times in the machine direction using the difference in speed between the ceramic rolls while heating the film so that the film temperature became 95 ° C. using four heaters. The roll diameter in the longitudinal stretching step was 150 mm, and the film was brought into close contact with the roll using a suction roll, electrostatic contact, and part nip contact apparatus. The both ends of the longitudinally uniaxially stretched film thus obtained are gripped with clips, preheated with hot dry air so that the film surface temperature is about 100 ° C., and then stretched 3.8 times in the transverse direction while heating to about 140 ° C. did. Thereafter, with the film width fixed, the film was heat-fixed by heating to about 230 ° C. with a surface infrared heater and dry hot air, and 5% relaxation heat treatment was performed in the width direction while cooling to about 200 ° C. Thereafter, the film is gradually cooled with dry hot air adjusted to 150 ° C. and 100 ° C., corresponding to room temperature, and the film surface temperature (sufficiently lower than the glass transition temperature of the thermal adhesive layer) is 50 ° C. or lower. The edge part was excised and it was set as the film roll. Thus, a heat-adhesive biaxially stretched white polyester film having a thickness of 190 μm was obtained. When the cross section of the film was observed with a scanning electron microscope, the thickness of each layer (thermal adhesive layer A / intermediate layer / thermal adhesive layer B) was approximately 20/150/20 (unit: μm).

  An IC card was prepared using this heat-adhesive biaxially stretched white polyester film, and suitability (thermal adhesion, unevenness absorbability, heat resistance) was evaluated. That is, two pieces of the film obtained above were cut into a size of 100 mm × 70 mm, and an IC tag inlet (V720S-D13P01, manufactured by OMRON Corporation) was arranged between them. A void-containing white polyester film (Toyobo Co., Ltd., Crisper K2323; 100 μm) was superposed on both outer surfaces of these two sheets and adhered by hot pressing (140 ° C., 0.3 MPa, 10 minutes). The laminate was cut into 86 mm × 54 mm so as to include the inlet portion, and the corners of the four corners were dropped to obtain an IC card. Table 1 shows the composition of the film, and Table 2 shows the characteristics of the film and card. The heat-adhesive polyester film obtained in Example 1 is a film having both thermal adhesiveness and unevenness absorbability and slipperiness suitable as a core sheet used for an IC card. In addition, the heat resistance, flatness, concealment and light weight were also suitable as an IC card.

Comparative Example 1
In Example 1, in place of the linear polyethylene resin, thermal adhesiveness was obtained in the same manner as in Example 1 except that a polyethylene terephthalate resin containing 5000 ppm of amorphous silica particles having an average particle size of 1.5 μm (SEM method) was used. A biaxially stretched white polyester film and an IC card were obtained. The heat-adhesive biaxially stretched white polyester film obtained in Comparative Example 1 has a thermal adhesive property and unevenness absorbability suitable for use as an IC card. It was not possible to measure. For this reason, even in the process of making an IC card, the handling property and the deviation due to thermal expansion could not be alleviated, and wrinkles and creases occurred.

Comparative Example 2
In Example 1, in place of the linear polyethylene resin, thermal bonding was performed in the same manner as in Example 1 except that a polyethylene terephthalate resin containing barium sulfate particles [50% by mass] having an average particle diameter of 3 μm (SEM method) was used. Biaxially stretched white polyester film and IC card were obtained. Although the heat-adhesive biaxially stretched white polyester film obtained in Comparative Example 2 has thermal adhesiveness and ruggedness absorbability suitable as a material for use as an IC card, the slipping property is extremely bad and the friction coefficient is low. It was not possible to measure. For this reason, even in the process of making an IC card, the handling property and the deviation due to thermal expansion could not be alleviated, and wrinkles and creases occurred.

Comparative Example 3
In Example 1, PET resin [100 mass%] is used as raw material M, and a mixture of amorphous polyester resin A [60 mass%] and linear low density polyethylene resin [40 mass%] is used as raw material C. Except for the above, a laminated biaxially stretched polyester film and an IC card were obtained in the same manner as in Example 1. The laminated biaxially stretched polyester film obtained in Comparative Example 3 was insufficient in thermal adhesiveness and concealment necessary for use as an IC card, and was inappropriate for the application.

Example 2
In Example 1, a mixture comprising a cavity forming agent-containing master pellet [6% by mass], a titanium oxide-containing master pellet [20% by mass], and the PET resin [74% by mass] was used as a raw material M. Moreover, the mixture which consists of amorphous polyester resin A2 [69 mass%], an organic particle containing master pellet [30 mass%], and a polyethylene resin (the Mitsui Chemicals company make, high wax 400P) [1 mass%] is used as raw material C It was. Except this, it carried out similarly to Example 1, and obtained the heat bondable polyester film and the IC card. The heat-adhesive polyester film obtained in Example 2 is a film having both thermal adhesiveness and unevenness absorbability and slipperiness suitable as a core sheet used for an IC card. In addition, the heat resistance, flatness, concealment and light weight were also suitable for IC cards.

Example 3
In Example 1, a raw material M was a mixture composed of a cavity forming agent-containing master pellet [15% by mass] and a PET resin [85% by mass]. Further, a mixture of amorphous polyester resin A2 [85% by mass] and high-density polyethylene resin (Idemitsu Petrochemical Co., Ltd., IDEMITSU HD 640UF; melting point 131 ° C., density 0.95 g / cm ³ ) [15% by mass] Used as raw material C. Furthermore, an unstretched film having a three-layer structure having a total thickness of 2.1 mm, in which the thicknesses of the thermal adhesive layers on both sides were different, was manufactured using three extruders. At this time, the thickness of each layer (thermal adhesive layer a / intermediate layer (base material) / thermal adhesive layer b) is discharged from each extruder so that it becomes 13/230/7 (unit: μm) after biaxial stretching. The amount of resin produced was adjusted. The thermal adhesive layer A is the surface in contact with the cooling drum. The obtained unstretched film was stretched in the same manner as in Example 1, but the temperature of the infrared heater was finely adjusted to make a difference between the front and back of the film so that the longitudinal curl after biaxial stretching was minimized. Except this, it carried out similarly to Example 1, and obtained the 250-micrometer-thick heat adhesive polyester film and IC card. The heat-adhesive polyester film obtained in Example 3 is a film that achieves both thermal adhesiveness, unevenness absorbability and slipperiness suitable for a core sheet used for an IC card. In addition, the heat resistance, concealment and light weight were also suitable as an IC card. As for the flatness of the film, some curling occurred in the vertical direction, but there was no practical problem in handling the film.

Comparative Example 4
In Example 3, the laminated thickness of the thermal adhesive layer a / intermediate layer (base material) / thermal adhesive layer b is discharged from each extruder so as to be 37/5/3 (unit: μm) after biaxial stretching. The amount of resin produced was adjusted. In addition, in the heating of the infrared heater in the longitudinal stretching step, no means for reducing the curl of the film by creating a temperature difference between the front and back of the film was employed. Except this, it carried out similarly to Example 3, and obtained the heat bondable polyester film. An inlet was disposed on the surface of the thermal adhesive layer b of the film so that the antenna circuit was opposed to the IC card, similarly to Example 1, to produce an IC card. In the heat-adhesive polyester film obtained in Comparative Example 4, both the heat-adhesiveness and the unevenness absorbability were insufficient. Also, curling at a level that makes it difficult to handle the film occurred. In addition, the curl value could not be measured because it could not stand on a flat surface. For this reason, handling is difficult even in the process of making an IC card, and positioning cannot be performed accurately when the inlet is bonded to the thermal adhesive layer of the thermal adhesive film.

Example 4
In Example 3, a mixture of titanium oxide-containing master pellets [30% by mass] and PET resin [70% by mass] was used as the raw material M. Further, a commercially available amorphous polyester resin A3 (Toyobo Co., Ltd., Byron 240; glass transition temperature 60 ° C.) “95% by mass” and gas phase method polypropylene resin (Idemitsu Petrochemical Co., Ltd., IDEMITSU PP F300SP; melting point 160 ° C., A non-stretched film consisting of a three-layer structure having a total thickness of 1.3 mm was produced using a mixture of density 0.90 g / cm ³ ) [5% by mass] as raw material C. At this time, the thickness of each layer (thermal adhesive layer a / white polyester layer (base material) / thermal adhesive layer b) was adjusted to 14/72/14 (unit: μm) after biaxial stretching. The amount of resin discharged from was adjusted. Except this, it carried out similarly to Example 1, and obtained the 100-micrometer-thick heat adhesive polyester film and IC card. The heat-adhesive polyester film obtained in Example 4 is a film having both thermal adhesiveness and unevenness absorbability and slipperiness suitable as a core sheet used for an IC card. Further, the heat resistance, concealability and flatness were suitable for IC cards.

Example 5
In Example 4, a mixture of amorphous polyester resin A3 [90% by mass] and polybutadiene resin (manufactured by Nippon Zeon, Nipol BR1220; melting point 95 ° C., density 0.90 g / cm ³ ) [10% by mass] is used as a raw material. Used as C. Except this, it carried out similarly to Example 4, and obtained the heat bondable polyester film and the IC card. The heat-adhesive polyester film obtained in Example 5 is a film having both thermal adhesiveness and unevenness absorbability and slipperiness suitable as a core sheet used for an IC card. In addition, the heat resistance, flatness, concealment and light weight were also suitable for IC cards.

Comparative Example 5
In Example 4, a mixture comprising amorphous polyester resin A3 [90% by mass] and polymethylpentene resin (manufactured by Mitsui Chemicals, TPX DX820; melting point 234 ° C., density 0.82 g / cm ³ ) [10% by mass] Was used as raw material C. Except this, it carried out similarly to Example 4, and obtained the lamination biaxial stretching white polyester film and the IC card. The laminated biaxially stretched white polyester film obtained in Comparative Example 5 had insufficient thermal adhesiveness as a core sheet used for an IC card, and was inappropriate for the application.

Comparative Example 6
In Example 4, a laminated biaxially stretched white polyester film and an IC card were obtained in the same manner as in Example 4 except that the amorphous polyester resin A as the raw material C was changed to a PET resin that was a crystalline polyester resin. The laminated biaxially stretched white polyester film obtained in Comparative Example 6 has insufficient thermal adhesiveness and unevenness absorbability necessary for a core sheet used for an IC card, and is inappropriate for the application. .

Comparative Example 7
As the raw material M, the raw material C of Example 1 was used. In order to ensure uniform mixing of the raw materials and stability during lamination, the raw material M was heated to 250 ° C. in the extruder and melted and mixed, and then led to a feed block at a resin temperature of 280 ° C. The thickness of the unstretched film was adjusted to 0.25 mm. Otherwise, the unstretched sheet was obtained in the same manner as in Example 1. An IC card was prepared in the same manner as in Example 1 by using this unstretched sheet instead of the heat-adhesive biaxially stretched white polyester film.

  The heat-adhesive white polyester film of the present invention is a biaxially stretched polyester film that is excellent in heat resistance, chemical resistance, and environmental suitability, and achieves both heat adhesion, uneven absorbability, and slipperiness that have been difficult so far. Thereby, the said characteristic which was not able to be achieved by the non-oriented PVC sheet | seat, PETG sheet | seat, biaxially stretched polyester film, or those bonding conventionally used for the IC card or the IC tag can be achieved. The present invention greatly contributes not only to improving the performance of the IC card or IC tag, but also to the economic effect due to the omission of the bonding process.

It is a schematic diagram of the cross section of the core sheet used for the IC card obtained in Example 1 of the present invention. It is a schematic diagram of the cross section of the core sheet used for the IC card or IC tag of another embodiment of the present invention. It is a schematic diagram of the cross section of the IC card or IC tag of the present invention. It is a schematic diagram of the cross section of the IC card or IC tag of another embodiment of the present invention.

Explanation of symbols

1: Thermal adhesive layer 2: Biaxially stretched polyester film 3: Inlet (3A + 3B + 3C)
3A: Plastic film (base material)
3B: Antenna circuit 3C: IC chip 4: Non-oriented polyester sheet or biaxially stretched polyester film

Claims (7)

A heat-adhesive white polyester film comprising a white biaxially stretched polyester film containing a white pigment and / or fine cavities inside as a base material, and a thermal adhesive layer laminated on one or both sides of the base material. And
The heat-adhesive white polyester film contains a large number of fine cavities inside the film, (a) the apparent density of the film is 0.7 to 1.3 g / cm ³ , (b) the thickness is 50 to 350 μm, and (c) optical. The concentration is 0.5-3.0,
The thermal adhesive layer has a thickness of 5 to 30 μm and is composed of a mixture of an amorphous polyester resin A having a glass transition temperature of 50 to 95 ° C. and a thermoplastic resin B incompatible therewith, and the thermoplastic resin B has a melting point. Is a crystalline resin having a temperature of 50 to 180 ° C., and is contained in an amount of 1 to 30% by mass in the thermal adhesive layer. A thermal adhesive white polyester film for an IC card or an IC tag. The heat-adhesive white polyester film has a heat-adhesive layer laminated on both sides of a biaxially stretched polyester film, one heat-adhesive layer as a heat-adhesive layer a, and the other heat-adhesive layer b (thickness is the same as the heat-adhesive layer a). The thickness ratio of the thermal adhesive layer (the thickness of the thermal adhesive layer a / the thickness of the thermal adhesive layer b) is 1.0 to 2.0, and the film The heat-adhesive white polyester film for IC card or IC tag according to claim 1 , wherein the curl value after heat treatment (110 ° C, 30 minutes under no load) is 5 mm or less. The heat-adhesive white polyester film for an IC card or IC tag according to claim 1 or 2 , wherein the surface of the heat-adhesive layer satisfies the following formulas (1) to (3).
1.0 ≦ St1 ≦ 10.0 (1)
3.0 ≦ St1 / Sa1 ≦ 20 (2)
0.001 ≦ St2 ≦ 3.000 (3)
In the above formulas (1) to (3), Sa1 means the arithmetic average surface roughness of the surface of the thermal adhesive layer, and St1 means the maximum height. St2 is a thermal adhesive layer after a film is sandwiched between two clean glass plates having an arithmetic average surface roughness of 0.001 μm or less and subjected to a hot press treatment at a temperature of 100 ° C. and a pressure of 1 MPa for 1 minute. Means the arithmetic average surface roughness of the surface. The unit of Sa1, St1, and St2 is all μm. The IC card or IC tag according to any one of claims 1 to 3 , wherein a coefficient of static friction measured by superposing one side and the other side of the heat-adhesive white polyester film is 0.1 to 0.8. Thermal adhesive white polyester film. The thermal adhesive film according to any one of claims 1 to 4 is disposed on one side or both sides of an inlet provided with an antenna circuit and an IC chip on a plastic film, and the inlet is provided via a thermal adhesive layer of the thermal adhesive film. An IC card or IC tag manufacturing method, wherein a core sheet bonded by hot pressing is used as a constituent element. The thermal adhesive film according to any one of claims 1 to 4 is laminated on one side or both sides of an inlet provided with an antenna circuit and an IC chip on a plastic film, and the inlet and the thermal adhesive layer of the thermal adhesive film are interposed therebetween. An IC card or an IC tag comprising an adhered core sheet as a constituent element. 7. The IC card or IC tag according to claim 6 , wherein a polyester sheet or a biaxially stretched polyester film is laminated on both surfaces of the core sheet.

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