Plastic card provided with magnetic stripe

• US 5,720,500 A
• Filed: 01/16/1996
• Issued: 02/24/1998
• Est. Priority Date: 02/02/1993
• Status: Expired due to Term

• Current Assignee: Dai Nippon Printing Company Limited, JCB Company Limited
• Original Assignee: Dai Nippon Printing Company Limited, JCB Company Limited
• Inventors: Sasaki, Yoshiki, Okazaki, Masaaki, Kitami, Koji
• Primary Examiner(s): NAKARANI, DHIRAJLAL S
• Application Number:
  US08/585,809
• Time in Patent Office: 770 Days
• Field of Search: 235/457, 235/449, 235/493, 283/82, 283/86, 283/83, 283/91, 283/94, 283/101, 283/107, 283/109, 283/904, 359/3, 428/500, 428/213, 428/215, 428/414, 428/424.6, 428/475.8, 428/476.3, 428/483, 428/518, 428/520, 428/900
• US Class Current: 283/82
• CPC Class Codes: G03H 2250/12 Special arrangement of layers
• CPC Class Codes: G06K 19/06196 Constructional details
• CPC Class Codes: Y10S 283/904 Credit card
• CPC Class Codes: Y10S 428/90 Magnetic feature
• CPC Class Codes: Y10T 428/2495 Thickness [relative or absolute]
• CPC Class Codes: Y10T 428/24967 Absolute thicknesses specified
• CPC Class Codes: Y10T 428/31515 As intermediate layer
• CPC Class Codes: Y10T 428/3158 Halide monomer type [polyvinyl chloride, etc.]
• CPC Class Codes: Y10T 428/31743 Next to addition polymer from unsaturated monomer[s]
• CPC Class Codes: Y10T 428/3175 Next to addition polymer from unsaturated monomer[s]
• CPC Class Codes: Y10T 428/31797 Next to addition polymer from unsaturated monomers
• CPC Class Codes: Y10T 428/3192 Next to vinyl or vinylidene chloride polymer
• CPC Class Codes: Y10T 428/31928 Ester, halide or nitrile of addition polymer

Abstract

A plastic card provided with a magnetic stripe, which is very difficult to forge or alter and, even tough subjected to forgery or alteration, enables the forgery or alteration to be easily detected in appearance. The plastic card includes a card substrate and a hologram-magnetic stripe including, provided on said card substrate in the following order, an adhesive layer, a first magnetic recording layer, a second magnetic recording layer, a transparent continuous thin film layer and a hologram forming layer. The first magnetic recording layer and the second magnetic recording layer are such that one of the magnetic recording layers has a coercive force at least twice as high as the other magnetic layer and a Curie point at least 100° C. below the other magnetic layer and, when the magnetic recording layers are heated at a temperature in the range of from the lower Curie point to 30° C. below the lower Curie point, they become substantially identical to each other in saturation writing current value.

Claims

1. A plastic card provided with a magnetic stripe, the plastic card comprising:

a card substrate comprising polyvinyl chloride; and

a hologram-magnetic stripe formed on said card substrate, said hologram-magnetic stripe comprising a magnetic recording layer and a hologram formed on said magnetic recording layer, said magnetic recording layer comprising first and second magnetic recording layers, said first magnetic recording layer having a coercive force at least twice as high as that of said second magnetic recording layer and a Curie point at least 100°

C. below that of said second magnetic recording layer, such that when said first and second magnetic recording layers are heated at a temperature ranging from said lower Curie point to 30°

C. below said lower Curie point, said first and second magnetic recording layers become substantially identical to each other in saturation writing current value, whereby magnetic information can be written on both said magnetic recording layers simultaneously;

said hologram comprising a hologram forming layer adhered to said magnetic recording layer by an optically transparent continuous film layer, wherein said optically transparent continuous film layer has a refractive index different from that of said hologram forming layer.

2. The plastic card of claim 1, further comprising an adhesive layer between said hologram-magnetic stripe and said card substrate, wherein the adhesive layer comprises a resin selected from the group consisting of acrylic resin, vinyl resin, polyester resin, urethane resin, amide resin, epoxy resin, rubber resin and an ionomer resin.

3. The plastic card of claim 1, wherein a thickness of said first and second magnetic recording layers ranges from 1 to 100 μ

m if coated, or 100 Å

to 1 μ

m if vacuum deposited, sputtered or plated.

4. The plastic card of claim 1, wherein said optically transparent continuous film has a higher refractive index than that of said hologram forming layer.

5. The plastic card of claim 1, wherein said optically transparent continuous film has a lower refractive index than that of said hologram forming layer.

6. The plastic card of claim 1, wherein said hologram forming layer consists of acrylic and melamine resin.

7. A method for recording magnetic information, comprising the steps of:

providing a plastic card provided with a magnetic stripe, the plastic card comprising a card substrate comprising polyvinyl chloride and a hologram-magnetic stripe formed on said card substrate, the hologram-magnetic stripe comprising a magnetic recording layer and a hologram formed on the magnetic recording layer, said magnetic recording layer comprising first and second magnetic recording layers, the first magnetic recording layer having a coercive force at least twice as high as that of the second magnetic recording layer and a Curie point at least 100°

C. below that of said second magnetic recording layer, such that when said first and second magnetic recording layers and heated at a temperature ranging from said lower Curie point to 30°

C. below said lower Curie point, said first and second magnetic recording layers become substantially identical to each other in saturation writing current value, said hologram comprising a hologram forming layer adhered to said magnetic recording layer by an optically transparent continuous film layer, wherein said optically transparent continuous film layer has a refractive index different from that of said hologram forming layer; and

recording magnetic information on both said magnetic recording layers simultaneously at a temperature ranging from said lower Curie point to 30°

C. below said lower Curie point.