JP4252998B2 - Card sheet and card - Google Patents

Description

  The present invention relates to a card sheet used for a magnetic card such as a credit card or a cash card, an IC card, and the like, and a card using the card sheet.

Cards such as magnetic cards and IC cards are generally printed on a white resin sheet called a core sheet, and then covered with a transparent resin sheet called an oversheet on both sides to protect the printed layer. A hot-press is performed to form a laminated body, and then the formed laminated body is punched and formed into a card shape. If necessary, the card is embossed or printed on the surface. Polyvinyl chloride resin (hereinafter also referred to as “PVC”) has been used as a card material because it is excellent in printability, embossability, and the like.
However, since environmental problems such as dioxins are a concern, in recent years, an alternative to non-PVC materials has been strongly desired due to the ecology boom. As an alternative material for PVC in the card field, for example, an amorphous polyester resin that is a dehydration condensate of terephthalic acid, ethylene glycol, and 1,4-cyclohexanedimethanol has been studied.
However, the sheet made of this non-crystalline polyester resin was subjected to screen printing under the same conditions using the same ink as in the case of the PVC sheet, and when the sheets were stacked, the ink was not easily dried. In some cases, so-called “show-through” occurs in which the ink of the lower sheet is transferred to the back surface of the sheet. In the case of a PVC sheet, part of the slow-drying solvent of the screen printing ink dries on the sheet surface, and at the same time, the remaining slow-drying solvent is absorbed within the sheet in a short time, and eventually the sheet In the case of a sheet made of polyester resin, the remaining slow-drying solvent is hardly absorbed inside the sheet, and eventually the sheet surface is dissolved. It is thought that it is from. As a result, when drying is performed under the same conditions as in the case of a PVC sheet, a slow-drying solvent remains long in the vicinity of the sheet surface, resulting in show-through.
In order to prevent this show-through, studies such as making the drying time longer than the PVC sheet and changing the solvent composition of the ink have been made. These changes are not realistic as they are often made. That is, these changes are not practical. Therefore, there has been a demand for a sheet that does not show through even when screen printing is performed under the same conditions as the PVC sheet.
When a card using an amorphous polyester-based resin sheet is embossed and stamped under the same conditions as a PVC card, the curl generated on the card (hereinafter referred to as “embossed curl”) becomes large, which is not preferable in appearance, In some cases, standards such as ISO and JIS were not satisfied. Further, since the card may be cracked by embossing (hereinafter referred to as “emboss crack”), an impact modifier is added to prevent this emboss crack phenomenon. However, when an elastomer such as an impact modifier is added to such an amount that an emboss crack improvement effect is exhibited, there is a problem that the flexural modulus decreases and the emboss curl increases.

  The present invention has been made to solve the above problems, and the object of the present invention is to prevent environmental problems and show-through does not occur even when screen printing is performed under the same conditions as in the case of PVC. And it is providing the card | curd sheet | seat which can reduce an emboss curl even if it performs embossing, and the card | curd using this card | curd sheet | seat.

In order to solve the above problems, the card sheet of the present invention is a multilayer sheet having a skin layer on at least one surface of a base layer, and the resin composition forming the skin layer is substantially amorphous. A resin composition comprising a basic aromatic polyester resin as a main component, 0.1 to 3.0% by mass of a lubricant and 8 to 30% by mass of an impact modifier, and forming the base layer is It contains 0 to 5% by mass of an improving agent.
Here, the thickness of the skin layer is preferably 5 to 25% of the total thickness of the multilayer sheet.
Further, the impact modifier may be a (meth) acrylic polymer.

The card of the present invention includes at least one of the card sheets.
Here, the said card | curd sheet | seat can be included independently as an oversheet and a core sheet, respectively.

  According to the present invention, it is a non-PVC card sheet, and even if screen printing and embossing are performed under the same conditions as in the case of PVC, no show-through occurs and embossing curl can be reduced. A card sheet can be provided. Further, if the card sheet is used, a card can be provided in which no show-through occurs and emboss curl can be reduced.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the present invention will be described in detail.
The card sheet of the present invention is a multilayer sheet having two or more layers having a skin layer on at least one surface of the base layer. However, this skin layer is a layer formed of a resin composition containing a non-crystalline aromatic polyester resin as a main component, containing a lubricant, and containing 8 to 30% by mass of an impact modifier. It is. If the impact modifier contained in the skin layer is less than 8% by mass, the effect of absorbing the solvent of the screen ink is hardly exhibited, and the effect of preventing the ink show-through is not sufficiently exhibited. Moreover, the embossing crack by embossing tends to arise. On the other hand, even if the content of the impact modifier is more than 30% by mass, the effect of preventing the ink show-through is not improved, that is, the effect is considered to be saturated, which is uneconomical. In addition, in this invention, the quantity of the impact modifier contained in a skin layer is 8-30 mass%, and the quantity of the impact modifier in the resin composition which forms a skin layer is 8-30 mass%. It means that there is.

  Examples of the impact modifier used in the present invention include acrylic polymers mainly composed of alkyl acrylates, methacrylic polymers mainly composed of alkyl methacrylates, and styrene-butadiene polymers, acrylonitriles containing conjugated dienes such as butadiene. Examples include butadiene-styrene polymers, methyl methacrylate-butadiene-styrene polymers, and silicone polymers containing polyorganosiloxane. Among these, acrylic polymers or methacrylic polymers are preferably used. Moreover, these impact modifiers can also be used in combination of 2 or more types.

Here, the polyester-based resin refers to a dehydration condensate of an aromatic dicarboxylic acid component and a diol component. Among them, the crystallinity is low, and even if heat processing that is practically performed such as press fusion is performed, the cloudiness due to crystallization Or that does not cause poor fusion.
Representative examples of the dicarboxylic acid component preferably used in the present invention include terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid and the like. Among these, terephthalic acid is particularly preferably used, but a part of terephthalic acid may be substituted with another dicarboxylic acid or the like. Examples of other dicarboxylic acid components include oxalic acid, malonic acid, succinic acid, adipic acid, azelaic acid, sebacic acid, neopentylic acid, isophthalic acid, naphthalene dicarboxylic acid, diphenyl ether dicarboxylic acid, p-oxybenzoic acid, and the like. . The other components such as dicarboxylic acid to be used may be one kind or a mixture of two or more kinds, and the amount of other dicarboxylic acid to be substituted can be appropriately selected.

  Representative examples of the diol component preferably used in the present invention include ethylene glycol, diethylene glycol, triethylene glycol, and cyclohexanedimethanol. Among these, ethylene glycol is particularly preferably used, but a part of ethylene glycol may be substituted with other components such as diol. Other components such as diol include propylene glycol, trimethylene glycol, tetramethylene glycol, hexamethylene glycol, diethylene glycol, neopentyl glycol, polyalkylene glycol, 1,4-cyclohexanedimethanol, glycerin, pentaerythritol, trimethylol, methoxy Examples include polyalkylene glycol. In addition, the other diol components used may be one kind or a mixture of two or more kinds, and the amount of other diols to be substituted can be appropriately selected. As the polyester-based resin used in the present invention, specifically, polyethylene terephthalate obtained by condensation polymerization of terephthalic acid and ethylene glycol is preferable from the viewpoint of cost, but other components such as dicarboxylic acid other than terephthalic acid and / or Copolyesters containing other diol components other than ethylene glycol can be used.

As the copolyester, 60 mol% or more of the dicarboxylic acid component is terephthalic acid, the dicarboxylic acid component in which the remaining dicarboxylic acid component is replaced with another component such as dicarboxylic acid, and 60 mol% or more of the diol component is ethylene. Examples thereof include copolymer polyesters obtained by condensation polymerization of a diol component in which the remaining diol component is replaced with another diol component or the like with glycol. The polyester resin in the present invention may be a mixture of polyethylene terephthalate and the above copolyester.
However, when using a copolyester, care must be taken because the glass transition temperature and tensile elastic modulus of the sheet vary greatly depending on the selection and content of the copolymer component.

  As the copolyester that can be used particularly preferably, a substantially amorphous aromatic polyester resin in which about 30 mol% of ethylene glycol in polyethylene terephthalate is substituted with 1,4-cyclohexanedimethanol is preferable. The trade name “PET G6763” manufactured by Man Chemical Co. can be obtained commercially.

  The base layer constituting the card sheet needs to be a layer formed from a resin composition containing 0 to 5% by mass of an impact modifier. (A base layer impact modifier of 0 to 5% by mass means that the amount of the impact modifier in the resin composition forming the base layer is 5% by mass or less.) Resin forming the base layer The composition preferably contains a substantially non-crystalline polyester resin, polycarbonate, or an alloy of polyester resin and polycarbonate as a main component.

Here, examples of the substantially non-crystalline polyester resin include the same ones as those used for the skin layer described above.
Polycarbonate means a resin composition whose main component is polycarbonate. Examples of the resin that can be mixed with the polycarbonate include trade name “PETG” manufactured by Eastman Chemical Co., Ltd.

  In addition, as a polymer alloy of a polyester resin and a polycarbonate used as a material for the base layer, for example, PETG or polybutylene terephthalate (hereinafter referred to as “PBT”) is used as a polyester resin, and a polymer of this and a polycarbonate An alloy is mentioned as a preferable thing. PBT is a dehydration condensate of terephthalic acid and 1,4-butanediol, and may be a homopolymer or a copolymer. Examples of the copolymer include those obtained by substituting a part of terephthalic acid with isophthalic acid. The composition ratio between the polyester resin of the polymer alloy and the polycarbonate can be appropriately set according to the purpose and the like, and it is desirable to design in consideration of the type and thickness of the card used.

  The card sheet of the present invention needs to contain a lubricant at least in the skin layer. The amount of the lubricant is preferably 0.1 to 3.0% by mass, particularly preferably 0.3 to 2.0% by mass in the resin composition forming each layer. If the content of the lubricant in the resin composition forming each layer is 0.1% by mass or more, it is possible to effectively prevent the sheet from sticking to the decorative board during carding by hot pressing. If it is 3.0% by mass or less, the printability on the sheet is not impaired. Preferred lubricants include higher fatty acids, higher alcohols, fatty acid esters and the like.

  In the present invention, a colorant may be added to each layer of the card sheet. By providing at least one layer to which a colorant is added, a concealing core sheet can be designed. A pigment can be used as the colorant. For example, a white pigment such as titanium oxide or barium sulfate can be used. In this case, the content of the colorant in each layer is preferably in the relationship of skin layer ≦ base layer. Mixing the colorant in this way works advantageously in designing a card sheet with excellent concealment, and effectively prevents emboss cracks when embossing the formed card. Can do. Therefore, when the skin layer has a higher pigment content than the base layer, it is considered that when the card is embossed, cracking proceeds from the card surface, leading to emboss cracking.

  In addition, a filler such as talc can be added to each layer of the card sheet. In this case, the filler content in each layer is preferably in the relationship of skin layer ≧ base layer. By blending the filler in this way, the stiffness of the sheet can be strengthened, which is advantageous in preventing emboss curl.

  As described above, in addition to impact modifiers, lubricants, colorants, fillers, etc. can be added to each layer of the card sheet. This will greatly affect the characteristics of sheets and cards. That is, when various characteristics such as embossability, emboss curl prevention property, and printability after being formed on the card are comprehensively considered, the amount of the impact modifier contained in each layer is skin layer> base layer. The amount of lubricant contained in the skin layer ≧ base layer, the amount of colorant contained in each layer is skin layer ≦ base layer, and the amount of filler contained in each layer is skin layer ≧ base layer It is preferable to satisfy these relationships at the same time, and it is most preferable from the viewpoint of overall balance.

  In addition, an antiblocking agent, an antistatic agent, a stabilizer, an ultraviolet absorber, a heterogeneous polymer, or the like can be added to each layer of the card sheet as necessary within the range not impairing the above effects and the like. .

  In the card sheet of the present invention, a skin layer is provided on at least one surface of the base layer. From the viewpoint of workability in the card manufacturing process, it is preferable to provide a skin layer on both surfaces. The base layer and the skin layer may each be a single layer or a multilayer.

  Although the thickness of the card | curd sheet | seat does not have limitation in particular, For example, it can select in the range of 30-800 micrometers. However, it is preferable that the thickness of one layer (including a single layer body and a multilayer body) of the skin layer is in the range of 5 to 25% of the thickness of the entire card sheet. If the thickness of the skin layer is less than 5% of the total thickness of the sheet, the absorption effect of the slow drying solvent may be difficult to be exhibited, and emboss cracks may occur due to embossing. On the other hand, if the thickness of the skin layer is more than 25%, the shrinkage stress increases with respect to the entire card sheet when the skin layer that has absorbed the solvent dries, which causes the card sheet to curl. This may reduce workability in the card manufacturing process.

  The card sheet can be produced, for example, by extrusion molding. The base layer resin composition and the skin layer resin composition are supplied to two extruders, co-extruded from a T die, and then cast rolls. By rapid cooling and solidification, a multilayer sheet having a layer structure of skin layer / base layer, skin layer / base layer / skin layer or the like can be obtained.

  The card sheet of the present invention preferably has a mat processing on at least one surface. The mat processing is not particularly limited. For example, it is preferable that continuous mat processing is performed such that the 10-point average roughness (Rz) of the surface is 5 μm or more and 30 μm or less. By providing such mat processing, the effect of preventing show-through is further increased. In addition, when Rz was 5 μm or more, when the sheets were laminated and heat-pressed, the air between the sheets and between the sheets and the decorative plate did not easily escape and was obtained. There is no defect in the appearance of the card. In addition, when Rz is 30 μm or less, there is no adverse effect that printing ink does not enter when printing on the surface, and printability is not hindered.

  When matting or matting is applied to the surface of the sheet, a mirror surface sheet is first formed, and then the surface is processed using a mat roll or matting roll, or the sheet is extruded. The surface may be processed by changing the cast roll into a mat roll or a matte roll during extrusion and performing extrusion molding. The design of the mat pattern or the like formed by mat processing can be determined as appropriate, and the commercial value of the sheet can be increased from an aesthetic viewpoint or a functional viewpoint.

  In general, a card is composed of, for example, a core sheet used as a middle layer of a card, an oversheet disposed on the surface of the card, and a magnetic stripe tape or an IC chip for recording information as necessary. The sheet is formed by stacking an oversheet on the core sheet and fusing the sheets by hot pressing or the like, and then punching the card shape. In the present invention, the card sheet refers to a sheet as a base material used for card manufacture, and includes sheets such as a core sheet and an oversheet.

The card of the present invention needs to include at least one sheet for card of the present invention, and can be used as, for example, a core sheet and / or an oversheet. Considering the contribution of the sheet thickness to the entire card, the card sheet of the present invention is preferably used as a core sheet, and more preferably used as a core sheet and an oversheet. When the card sheet of the present invention is used for both the core sheet and the oversheet, these card sheets may be the same or different. In addition, as a sheet other than the card sheet of the present invention used for the core sheet or oversheet, a normal core sheet or oversheet can be used. The oversheet may be transparent, and in the case of being transparent, the design printed on the core sheet can be seen through the card surface.
For example, printing is performed on the surface of the core sheet by silk screen printing, offset printing, etc., and the formed printing surface is covered with an oversheet, and if necessary, the other surface of the core sheet is also covered with an oversheet and temporarily attached. After that, it is sandwiched between decorative sheets and hot pressed to form a laminate. A punched card can be formed in a card shape from the obtained laminate with a punching blade.

In the present invention, the method for integrating the oversheet and the core sheet is not particularly limited, and examples thereof include a method using thermal fusion, an adhesive, and the like. In this invention, it is preferable to integrate by heat sealing | fusion. In addition, you may stick a magnetic tape on an oversheet beforehand.

EXAMPLES The present invention will be specifically described below using examples, but the present invention is not limited to these examples.
In addition, evaluation of the sheet | seat and card | curd in an Example and a comparative example was performed based on the evaluation method shown below.

Evaluation methods:
(1) Back-through A card sheet is cut into a size of 300 mm × 300 mm, and the same screen ink (trade name “CAD Indigo” Using Ink Manufacturing Co., Ltd.), solid printing was performed on the entire surface by a known screen printing method, followed by drying for 20 minutes in a hot air dryer at 50 ° C. However, the solid content concentration of the ink was adjusted so as to be 20% by mass, and printing was performed so that the ink had a coating amount of 20 g / m ² . After printing, 100 sheets of card sheets are stacked with the print side up and left at room temperature for 24 hours. Then, the lowermost card sheet and the upper card sheet are taken out, and the lowermost card sheet is removed. It was visually observed whether or not the printing was transferred to the back surface of the card sheet thereon. It was also confirmed whether the stacked sheets were not blocking each other. The symbol “×” indicates that the show-through has occurred, blocking has occurred, but there is no show-through and there is virtually no problem, the symbol “△”, and the case where no blocking or show-through has occurred, the symbol “○”. It showed in.

(2) Curling of card sheet after printing In the same manner as the evaluation of show-through, one of the card sheets subjected to screen printing was allowed to stand at room temperature for 24 hours. This card sheet was placed on a surface plate with the printing surface facing upward, and it was visually observed whether the card sheet was lifted (curled) at the end. The symbol “○” indicates that the end of the sheet is not lifted (curl), and the symbol “○” indicates that the sheet is lifted (curl) at the end of the sheet, but is judged to have no practical problem. A symbol “x” indicates that the end of the sheet is lifted by 3 mm or more.

(3) Emboss cracking of card In the same manner as the evaluation of show-through, two card sheets subjected to screen printing were used and overlaid in the order of oversheet / core sheet / core sheet / oversheet. However, it was arranged so that the printing surface was on the oversheet side. The stacked sheets are sandwiched between decorative plates, and are subjected to hot pressing at 120 ° C. for 10 minutes at a sheet surface pressure of 9.8 × 10 ⁵ Pa to integrate the sheets, then cooled to room temperature, and punched into a card shape Card.
The resulting card was embossed with 3 characters of 19 characters in 7B font using “Embosser DC-9000” manufactured by Nippon Data Card. The convex portions of the embossed characters were visually observed, and those with cracks were indicated with a symbol “x”, and those without cracks were indicated with a symbol “◯”.

(4) Embossing curl of card An embossed card produced in the evaluation of emboss cracking was placed on a surface plate with the embossed convex part on top, and the degree of curling was visually observed. The degree of curling is evaluated based on the provisions of JIS X 6305. Symbols “x” are not specified and symbols “○” are those whose maximum height including the card thickness is 2.5 mm or less. Those that can be regarded as equivalent to a PVC card are indicated by the symbol “◎”.

Example 1
A base layer resin composition was prepared based on the formulation CS1 shown in Table 1, and a skin layer resin composition was prepared based on the formulation CS4. That is, as the resin composition for the base layer, a substantially amorphous aromatic polyester (herein, “polyester A”) in which about 30 mol% of ethylene glycol in polyethylene terephthalate is substituted with 1,4-cyclohexanedimethanol. (Noted) and titanium oxide were blended in a proportion of 90% by mass of polyester A and 10% by mass of titanium oxide. Further, 81% by mass of polyester A as the resin composition for the skin layer, and 8% by mass of acrylic-silicone rubber (made by Mitsubishi Rayon Co., Ltd., “Metablene S-2001”) as an impact modifier as an impact modifier. In addition, 10% by mass of titanium oxide and 1% by mass of a fatty acid ester as a lubricant were blended. The base layer resin composition and the skin layer resin composition were charged into two extruders, and a laminate of two types and three layers was formed using the same-direction biaxial extruder. As shown in Table 2, the thickness ratio of each layer of the obtained laminate was skin layer / base layer / skin layer = 20/60/20. This laminate is referred to as a card sheet C.
The obtained card sheet C was evaluated for show-through and curling after printing. The results are shown in Table 2.

Examples 2-13
In Example 1, the resin composition for the skin layer and the resin composition for the base layer were changed to the formulations shown in Table 2 and Table 3, and the formulation of the formulation to be used was changed as shown in Table 1 to laminate Formed body. The thickness ratio between the skin layer and the base layer was changed as shown in Tables 2 and 3. As shown in Table 2, the obtained laminates are respectively card sheet D to card sheet J, card sheet L, card sheet N, card sheet P, card sheet Q, card sheet OA. It was.
About each obtained sheet | seat for cards, evaluation similar to Example 1 was performed. The results are shown in Tables 2 and 3.

Comparative Examples 1-5
In Example 1, the resin composition for the skin layer and the resin composition for the base layer were changed to the formulations shown in Table 2 and Table 3, and the formulation of the formulation to be used was changed as shown in Table 1 to laminate Formed body. The thickness ratio between the skin layer and the base layer was changed as shown in Tables 2 and 3. As shown in Tables 2 and 3, the obtained laminates were a card sheet A, a card sheet B, a card sheet K, a card sheet M, a card sheet O, and a card sheet OB, respectively. .
About each obtained sheet | seat for cards, evaluation similar to Example 1 was performed. The results are shown in Tables 2 and 3.

As is clear from Tables 2 and 3, the card sheets of the present invention of Examples 1 to 13 are free from show-through and the curl of the printed sheet is within a range where there is no practical problem. It turned out to be a thing. On the other hand, show-through occurred in the card sheets of Comparative Examples 1 and 2.
In addition, about the emboss crack, the card | curd was produced and the card | curd was evaluated. This is shown in Examples 14 to 26 and Comparative Examples 7 to 11.

Example 14
As shown in Table 4, the card sheet C was used as the core sheet, and the card sheet OB was used as the oversheet. Screen printing is performed on the skin layer of the core sheet, the printed surface of the core sheet is on the oversheet side, the oversheet / core sheet / core sheet / oversheet are stacked in this order and sandwiched between decorative sheets, the temperature is 120 ° C., Hot pressing was performed at a sheet surface pressure of 9.8E + 5 Pa for 10 minutes to integrate them, followed by cooling to form a laminate having a thickness of about 760 μm. The thickness of one core sheet is about 280 μm, and the thickness of one oversheet is about 100 μm. The obtained laminate was punched into a card shape to produce a card.
The obtained card was evaluated for emboss cracks and emboss curls. The results are shown in Table 4. The show-through of the card sheet and the curl after printing the sheet are also displayed again in Table 4.

Examples 15 to 26 and Comparative Examples 7 to 11
A card was produced in the same manner as in Example 14 except that the core sheet and oversheet used in Example 14 were changed as shown in Table 4.
The obtained card was evaluated in the same manner as in Example 14. The results are shown in Table 4. The show-through of the card sheet and the curl after printing the sheet are also displayed again in Table 4.

As is clear from Table 4, the cards of Examples 14 to 26 using the card sheet of the present invention as a core sheet are free from embossing cracks after embossing, and the embossed curl is also practical. It was found to be within the range. Moreover, it turned out that the card | curd of Example 26 which uses the sheet | seat for cards of this invention also for the oversheet is a further superior thing in evaluation of an emboss curl. Moreover, the card sheets used in Examples 14 to 26 were good both in evaluation of show-through and evaluation of curl after printing. That is, it was found that the card sheet of the present invention was good in all the evaluations of show-through and emboss curl.
On the other hand, the card of Comparative Example 7 had emboss cracks, and it was found that the cards of Comparative Examples 9 to 11 had large embossed curls and were out of the practical range. In the card of Comparative Example 8, the card sheet B was inferior in evaluation of show-through. Therefore, the cards of Comparative Examples 7 to 11 were inferior in at least one of show-through and emboss curl.

Claims (8)

A multilayer sheet having a skin layer on at least one surface of a base layer, wherein the multilayer sheet is a coextruded multilayer sheet, and the resin composition forming the skin layer is a substantially non-crystalline aromatic polyester A resin composition containing a resin as a main component, containing 0.1 to 3.0% by mass of a lubricant and 8 to 30% by mass of an impact modifier, and forming the base layer comprises An oversheet for cards, containing 5% by mass. The card oversheet according to claim 1, wherein the thickness of the skin layer is 5 to 25% of the total thickness of the multilayer sheet . The card oversheet according to claim 1, wherein the impact modifier is a (meth) acrylic polymer. A multilayer sheet having a skin layer on at least one surface of a base layer, wherein the multilayer sheet is a coextruded multilayer sheet, and the resin composition forming the skin layer is a substantially non-crystalline aromatic polyester A resin composition containing a base resin as a main component, containing 0.1 to 3.0% by mass of a lubricant and 8 to 30% by mass of an impact modifier, and forming the base layer comprises A core sheet for cards, containing 5% by mass. 5. The card core sheet according to claim 4 , wherein the thickness of the skin layer is 5 to 25% of the total thickness of the multilayer sheet . 6. The card core sheet according to claim 4 , wherein the impact modifier is a (meth) acrylic polymer. Card, characterized in that it comprises at least one sheet card over sheet or the core sheet card as claimed in any one of claims 1 to 6. The card oversheet according to any one of claims 1 to 3 is used as an oversheet, and the card core sheet according to any one of claims 4 to 6 is used as a core sheet independently. The card according to claim 7 , wherein the card is included.