Optical recording medium
AssigneeSony Corporation
InventorsTakeshi Yamasaki, Tomomi Yukumoto, Toshiyuki Kashiwagi
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Abstract
An optical recording medium capable of improving uniformity of thickness of a protective film and suppressing warping. The medium is configured to include a substrate, an optical recording film formed on the substrate, and a light transmitting protective film formed above the optical recording layer, wherein the protective film includes a polymer sheet produced by melt casting and an adhesive layer for bonding the polymer sheet to the optical recording layer. As the polymer sheet, a polycarbonate sheet, a cyclic polyolefin sheet, etc. can be used. As the adhesive layer, an ultraviolet curing resin, a heat curing resin, an epoxy resin-based adhesive agent or a pressure-sensitive tackiness agent may be used alone or mixed or stacked.
Claims6
An optical recording medium comprising:
- a substrate;
- an optical recording layer formed on said substrate;
- and
- a light transmitting protective film formed at an upper layer of said optical recording layer;
- wherein said protective film includes a polymer sheet produced by melt casting and an adhesive layer for bonding the polymer sheet to said optical recording layer;
- and
- wherein a residual solvent in said polymer sheet is not more than 0.3 wt %.
An optical recording medium comprising:
- a substrate;
- an optical recording layer formed on said substrate;
- and
- a light transmitting protective film formed at an upper layer of said optical recording layer;
- wherein said protective film includes a polymer sheet produced by melt casting and an adhesive layer for bonding the polymer sheet to said optical recording lever;
- and
- wherein said adhesive layer comprises a stack of a ultraviolet curing resin-based adhesive agent layer and a pressure-sensitive tackiness agent layer.
Dependencies are inferred from the claim text.