Multiple layer optical record medium with protective layers and method for producing same

• US 5,364,735 A
• Filed: 08/27/1992
• Issued: 11/15/1994
• Est. Priority Date: 07/01/1988
• Status: Expired due to Fees

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Yamamura, Masato, Akamatsu, Junichi
• Primary Examiner(s): Wright, Lee C.
• Application Number:
  US07/935,464
• Time in Patent Office: 810 Days
• Field of Search: 430/271, 430/272, 430/273, 430/321, 430/495, 430/496, 430/945, 430/523, 430/531, 369/275.5, 369/283, 369/284, 369/285, 369/286, 427/162, 427/164, 427/289, 427/177, 427/428, 427/293, 283/904, 283/93, 283/94, 283/109
• US Class Current: 430/270.12
• CPC Class Codes: G11B 2007/24314 group 15 elements (e.g. Sb, Bi)
• CPC Class Codes: G11B 2007/24316 group 16 elements (i.e. chalcogenides, Se, Te)
• CPC Class Codes: G11B 7/0033 with cards or other card-like flat carriers, e.g. flat sheets of optical film
• CPC Class Codes: G11B 7/24053 Protective topcoat layers lying opposite to the light entrance side, e.g. layers for preventing electrostatic charging
• CPC Class Codes: G11B 7/2534 polycarbonates [PC]
• CPC Class Codes: G11B 7/2542 consisting essentially of organic resins
• CPC Class Codes: G11B 7/256 of layers improving adhesion between layers
• CPC Class Codes: G11B 7/2575 resins
• CPC Class Codes: G11B 7/2585 based on aluminium
• CPC Class Codes: G11B 7/26 Apparatus or processes specially adapted for the manufacture of record carriers
• CPC Class Codes: Y10S 430/146 Laser beam

Abstract

An optical recording medium in which a recording layer (4) on which optically readable data are recorded is formed on a rectangular base material (1), a protective layer (5) is formed by roll coating on the recording layer (4) and wherein the base material (1) on which the recording layer (4) and the protective layer (5) have been formed is cut into a predetermined shape. The protective layer (5) provided on the recording layer (4) is formed of a material having a low Young modulus and a lower thermal conductivity as compared with the base material.

Claims

1. An optical recording medium comprising:

a light transmissive base plate having a rectangular shape and being of a size for forming into a plurality of smaller, uniform shapes,

a first protective layer formed of UV curing resin provided on a surface of said base plate,

a metal recording layer which is provided on said first protective layer and containing data which may be optically read out,

a second protective layer formed of UV curing resin provided on said recording layer by roll coating, and

a polyester protective film adhered to said second protective layer by means of an adhesive layer applied between said protective film and said second protective layer.

2. The optical recording medium according to claim 1 wherein said second protective layer is formed of a material having a Young modulus of elasticity not higher than 2×

10¹⁰ dyn/cm².

4. The optical recording medium according to claims 1 or 2 wherein said second protective layer is formed of a material having a lower thermal conductivity than the base material or the base plate.

5. The optical recording medium according to claims 1 or 2 wherein the smaller, uniform shape of said base plate having said recording layer, first and second protective layers, and protective film following dividing has the form of a rectangular card.

6. The optical recording medium according to claims 1 or 2 wherein the smaller, uniform shape of said base plate having said recording layer, first and second protective layers, and protective film following dividing has the form of a disk.

3. An optical recording medium comprising:

a base plate having light transmissivity and being of a size for forming into a plurality of smaller, uniform shapes,

a first protective layer formed of UV curing resin provided on a surface of said base plate,

a recording layer provided on said first protective layer and on which optically readable data are recorded,

a second protective layer formed of UV curing resin provided on said recording layer and having a lower modulus of elasticity than a modulus of elasticity of said base plate and having a Young modulus of elasticity not higher than 2×

10¹⁰ dyn/cm², and

a protective film formed of polyester adhered to said second protective layer by means of an adhesive layer applied to said protective film.