JP2000273197A - Overlay sheet for card and card - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prepare an overlay sheet which is formed by applying an aqueous heat-sealing adhesive layer having a sufficient adhesion property for attaching a printing ink and an overlay sheet to improve the designability and reliability of cards. SOLUTION: To one side of a transparent thermoplastic resin sheet substrate having a thickness of from 30 to 200 ×m, a heat-sensitive adhesive layer 2 is formed to prepare a structure. Here, the heat-sensitive adhesive layer is a resin layer formed by applying and drying an aqueous emulsion of a mixture of an ethylene/vinyl acetate copolymer resin and a chlorinated polypropylene. Preferably, the vinyl acetate content in the ethylene/vinyl acetate copolymer resin is from 40 to 80 wt.%, and the chlorine content in the chlorinated polypropylene is from 10 to 40 wt.%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plastic card such as a magnetic card, an IC card, and a scratch card, and an overlay sheet.

[0002]

2. Description of the Related Art A plastic card represented by a magnetic card, particularly a card having a thickness of more than 0.5 mm, is called an overlay in which a base material called a core material is printed and both sides or one side thereof is protected with a printed layer. In many cases, transparent sheets are laminated. For example, a cash card has a structure in which a pattern, characters, and the like are printed on a white thermoplastic resin sheet (core material), and then a transparent sheet (overlay) is overlaid on both sides and fused by hot pressing. Generally, pattern printing of these cards is performed by a method such as offset printing or silk printing, and ultraviolet curable inks such as polyester acrylate, polyurethane acrylate, and epoxy acrylate are used as printing inks. A rigid vinyl chloride sheet or polyester sheet used for an overlay or a core material of a card is excellent in heat-sealing property between these materials, but is insufficient in heat-sealing property with the printing ink. Therefore, in order to prevent the peeling of the overlay, the peripheral portion of the card is formed into a design in which the core material is exposed without printing, or a special ink having a good adhesion to the overlay sheet is used. 2. Description of the Related Art In recent years, there has been an increasing demand for a type of card in which pattern design is performed by offset printing on the entire surface of the card to improve the design and differentiate the card. However, due to the above-mentioned problems, the conventional method has restrictions on designs and colors, which hinders improvement in design. Therefore, in order to improve the adhesion between the printing ink and the overlay sheet,
Attempts have been made to provide an adhesive layer on the overlay by applying or printing an ethylene-vinyl acetate copolymer or urethane resin-based heat-seal adhesive, and heat-seal it with the printed layer during pressing. Even with the agent, adhesion with the ink was obtained, but adhesion with the overlay was insufficient, and satisfactory results were not obtained. Hard vinyl chloride and amorphous polyester used for card materials have poor solvent resistance, and in recent years, the overlay sheet tends to be thin, so that a solvent-based adhesive cannot be used as a heat sealant. In addition, from the viewpoints of working environment and air pollution, a water-based adhesive is required rather than a solvent-based adhesive. Therefore, there is a strong demand for a water-based heat seal adhesive which can provide sufficient adhesion between the overlay sheet and the ultraviolet curable printing ink.

[0003]

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide a printing ink and an overlay sheet with sufficient adhesion in order to improve the design of the card design and improve the reliability of the card. An object of the present invention is to provide an overlay sheet formed by applying a water-based heat-sealable adhesive layer having a property.

[0004]

According to the present invention, there is provided a method for manufacturing a semiconductor device, comprising:
In a structure in which a heat-sensitive adhesive layer is provided on one side of a transparent thermoplastic resin sheet base material of 00 μm, the heat-sensitive adhesive layer is an aqueous emulsion of a mixture of an ethylene-vinyl acetate copolymer resin and chlorinated polypropylene. This is an overlay sheet for a card, which is a resin layer formed by coating and drying. In a preferred embodiment, the ethylene-vinyl acetate copolymer resin has a vinyl acetate content of 40 to 80% by weight.
And the chlorine content of the chlorinated polypropylene is 10 to 4
This is an overlay sheet for a card, which is 0 wt% and a mixture ratio of chlorinated polypropylene is 10 to 50 wt% in a mixture of ethylene-vinyl acetate copolymer and chlorinated polypropylene. A further preferred embodiment is an overlay sheet for a card, wherein the thermoplastic resin sheet is a hard vinyl chloride resin or a polyethylene terephthalate-1,4 cyclohexane dimethanol copolymer resin. Furthermore, the present invention is a card using the card overlay sheet.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION It is preferable to use a rigid vinyl chloride or polyethylene terephthalate-1,4-cyclohexanedimethanol copolymer resin sheet as a base material of an overlay sheet in the present invention. Hard vinyl chloride used in the present invention refers to a vinyl chloride resin, which is mainly composed of a vinyl chloride homopolymer and / or a vinyl chloride copolymer. Examples of the copolymer to be copolymerized include vinyl acetate. , Ethylene, propylene and the like. If necessary, additives such as a stabilizer, a lubricant, a reinforcing agent, a filler, an ultraviolet absorber, and a coloring agent may be used. Similarly, polyethylene terephthalate-1,4
Various additives may be used for the cyclohexane dimethanol copolymer resin sheet as needed. The method for producing these base sheets is not particularly limited, but they are produced by a production method such as a calendar method, an extrusion method, and a press method.

[0006] The thickness of the overlay sheet substrate is 30 to 2
It is 00 μm, preferably 50 to 100 μm. 30μ
If it is less than m, it shrinks due to the heat of the drying furnace when applying and drying the heat-sensitive adhesive layer, and if it becomes thicker than 200 μm, it curls due to the curl when cut from a roll to every leaf for pressing, workability and yield. Is significantly reduced. An aqueous emulsion composed of a mixture of an ethylene-vinyl acetate copolymer resin and chlorinated polypropylene is applied to one surface of the overlay sheet by a known method such as a gravure method, a roll method, and a knife method, and dried to form a heat-sensitive adhesive layer. Form. In the present invention, the thickness of the heat-sensitive adhesive layer is not particularly limited, but is preferably 3 to 30 μm, and more preferably 5 to 15 μm.
Is preferred. If the heat-sensitive adhesive layer is too thin, sufficient adhesion strength cannot be obtained.If it is too thick, it melts during hot pressing with the card core material and flows out, causing cracks in the printed layer or uneven card thickness. Or become.

The ethylene-vinyl acetate copolymer resin used in the aqueous emulsion has a vinyl acetate content of 40 to 40.
80 wt% is preferable, and 50 to 70 wt% is more preferable. When the content of vinyl acetate is high, heat resistance and stability are reduced, and when it is too low, sufficient adhesiveness cannot be obtained. The method for producing the ethylene-vinyl acetate copolymer used in the present invention is not particularly limited, but when a resin produced in a powder form such as a high-pressure method is used, the resin is pulverized to a required size and emulsified. And used as an emulsion. In the case of a resin produced by an emulsification method, an emulsified liquid may be used as it is, or a resin powder once dried may be pulverized to a required size and emulsified to form an emulsion.

[0008] The chlorinated polypropylene used in the present invention preferably has a chlorine content of 10 to 40 wt%, more preferably 15 to 30 wt%. When the chlorine content is low, sufficient adhesiveness cannot be obtained, and when it is too high, transparency is impaired, which is not preferable. The chlorinated polypropylene emulsion is obtained by pulverizing a resin to a required size and then performing an emulsification treatment to form an emulsion. An ethylene-vinyl acetate copolymer resin and an emulsion of chlorinated polypropylene are mixed to form an adhesive. The mixing ratio is preferably such that the chlorinated polypropylene resin has a solid content of 10 to 50 wt%.

The emulsion of these resins may be any of anions, cations, and nonions, but it is necessary to unify them when mixing. If necessary, additives such as an emulsifier, a stabilizer, an antioxidant, an ultraviolet absorber, an antiblocking agent, a crosslinking agent, and an antifoaming agent may be used in each emulsion. Further, a magnetic recording layer, a semiconductor chip such as an IC, an optical recording layer, and the like may be provided to the overlay sheet provided with the heat-sensitive adhesive layer, as necessary.

[0010] A card is manufactured using the overlay sheet provided with the heat-sensitive adhesive layer as described above. Print the pattern of the card on one or both sides of the core material of the card, which is colored white etc., and place the overlay sheet with the heat-sensitive adhesive layer on both sides of the printed core material so that the printed surface and the adhesive layer match. And press it between the press plates. Thereafter, a punched card is manufactured to a predetermined card size. The core material is generally hard vinyl chloride resin,
Polyester resins such as polyethylene terephthalate and polyethylene terephthalate-1,4-cyclohexanedimethanol copolymer, ABS resins and the like are used. In addition, the core material is printed with the front and back patterns of the card on both sides with one sheet (the form of FIG. 1), or the front and back patterns are printed separately on one side with two sheets (FIG. 2). Form). Further, if necessary, a semiconductor chip such as an IC or an optical recording material may be provided to the core material.

Hereinafter, the present invention will be described specifically with reference to Examples and Comparative Examples.

<Example 1> The content of vinyl acetate was 60 wt.
% Of an ethylene-vinyl acetate copolymer resin powder was emulsified to prepare an aqueous emulsion (A1) having a solid content of 45%. Further, a chlorinated polypropylene having a chlorine content of 16 wt% was emulsified to prepare an aqueous emulsion (B1) having a solid content of 30%. Aqueous emulsions (A1) and (B
1) was mixed at 7: 3 to form an adhesive. In this case, the ratio of the chlorinated polypropylene in the mixture is 22.2 wt%. The adhesive obtained in this manner is 100 μm thick.
Was applied by a kiss-roll method so that the thickness after drying became 10 μm, and dried to prepare an overlay sheet with a heat-sensitive adhesive. <Example 2> 100 μm thick overlay sheet base material
Using the transparent polyethylene terephthalate-1,4 cyclohexane dimethanol copolymer resin sheet described above, an overlay sheet with an adhesive was produced in the same manner as in Example 1.

Comparative Example 1 An emulsion was prepared by mixing the emulsions (A1) and (B1) used in Example 1 at a ratio of 9: 1. The ratio of chlorinated polypropylene in the mixture is 6.
9 wt%. This adhesive was applied to a thickness of 1 as in Example 1.
It was applied on a transparent hard vinyl chloride sheet of 00 μm and dried to produce an overlay sheet with a heat-sensitive adhesive. <Comparative Example 2> Ethylene-vinyl acetate copolymer resin powder having a vinyl acetate content of 30 wt% was emulsified to obtain a solid content of 4%.
A 5% aqueous emulsion (A2) was prepared. Emulsion (A2) and emulsion (B used in Example 1)
1) was mixed at a ratio of 7: 3 to prepare an adhesive. The ratio of the chlorinated polypropylene in the mixture is 22.2 wt%. This adhesive was applied to a transparent hard vinyl chloride sheet having a thickness of 100 μm and dried in the same manner as in Example 1 to produce an overlay sheet with an adhesive. Comparative Example 3 A chlorinated polypropylene having a chlorine content of 8 wt% was emulsified to prepare an aqueous emulsion (B2) having a solid content of 30%. The emulsion (A1) and the emulsion (B2) used in Example 1 were mixed at a ratio of 7: 3 to prepare an adhesive. The ratio of the chlorinated polypropylene in the mixture is 22.2 wt%. This adhesive was used in Example 1.
In the same manner as described above, a 100 μm-thick hard vinyl chloride sheet was applied and dried to produce an overlay sheet with an adhesive.

The overlay with the heat-sensitive adhesive obtained as described above was carded by the following method, and the adhesion was evaluated. A black polyester acrylate ultraviolet curable offset ink was solid-printed on one surface of a core material made of a white hard vinyl chloride sheet having a thickness of 280 μm as an adherend. As shown in FIG. 2, two printed core materials are aligned with the unprinted surfaces, and the adhesive layer of the overlay with the adhesive is fitted on both sides thereof with the printed surface of the core material. Stacked and heat pressed. The hot press is performed at 110 kg / cm ² using a stainless steel press plate.
C. and 130.degree. C. for 10 minutes. After sufficiently cooling, a test piece having a width of 10 mm was prepared, and the adhesion strength between the overlay and the printed portion of the core material was measured. The adhesion strength was measured using a tensile tester, 50 m
The peeling was performed at 180 ° C. at a speed of m / min. Peel strength 1
It was judged that the adhesion was good at kg / 10 mm or more.
Table 1 shows the evaluation results.

[0014]

[Table 1]

[0015]

According to the present invention, it is possible to produce an overlay sheet having good adhesion to an ultraviolet curable printing ink, and to produce a card having a high degree of freedom in printing design and a stable quality.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an embodiment of a card using an overlay sheet according to the present invention.

FIG. 2 is a cross-sectional view of another embodiment of a card using an overlay sheet according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Overlay base material 2 ... Heat sensitive adhesive layer 3 ... Overlay sheet with heat sensitive adhesive according to the present invention 4 ... Printed pattern 5 ... Core material

Continued on the front page F-term (reference) 2C005 HA06 HB20 JA01 JA26 KA37 LA03 4F071 AA15 AA15A AA15X AA24 AA24B AA28 AA28A AA28X AA45 AA45B AA45X AA46 AA46B AA46X AA76 AA79 BA01 AK01 CB02 JB16A JK06 JK12A JL00 JL12B JM01B JN01A YY00A YY00B

Claims (5)

[Claims] 1. A structure in which a heat-sensitive adhesive layer is provided on one side of a transparent thermoplastic resin sheet base material having a thickness of 30 to 200 μm, wherein said heat-sensitive adhesive layer comprises an ethylene-vinyl acetate copolymer resin and chlorine. An overlay sheet for a card, which is a resin layer formed by applying and drying an aqueous emulsion of a mixture with a functionalized polypropylene. 2. The overlay sheet for a card according to claim 1, wherein the ethylene-vinyl acetate copolymer resin has a vinyl acetate content of 40 to 80% by weight, and the chlorinated polypropylene has a chlorine content of 10 to 40% by weight. 3. The card overlay sheet according to claim 1, wherein the mixture ratio of the chlorinated polypropylene in the mixture of the ethylene-vinyl acetate copolymer and the chlorinated polypropylene is 10 to 50 wt%. 4. The thermoplastic resin sheet is a rigid vinyl chloride resin or a polyethylene terephthalate-1,4-cyclohexanedimethanol copolymer resin.
Or the overlay sheet for cards according to 3. 5. A card using the overlay sheet according to claim 1, 2, 3, or 4.