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US 5,490,131 AGranted
Optical disk
AssigneeSharp Kabushiki Kaisha
InventorsKenji Ohta, Toshikazu Nagaura, Masayasu Futagawa, Shinji Yamagami, Yoshiteru Murakami, Hiroyuki Ikenaga, Michinobu Mieda, Tetsuya Inui, Akira Takahashi
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Abstract
An optical disk including a transparent plastic substrate, a recording film formed on an one side surface of said substrate, a first protective film covering said recording film, and a moisture-impermeable film formed on the other side surface of said substrate via or not via an intermediate film.
Claims29
An optical disk comprising:
- a) a transparent plastic substrate;
- b) a recording film formed on one side surface of said substrate;
- c) a first protective film covering said recording film;
- and
- d) a moisture-impermeable film formed on the other side of said substrate;
- wherein at least one of the first protective film and the moisture-impermeable film is coated with a synthetic resin film containing a powder of a transparent conductive material;
- wherein the moisture impermeable film is further covered with a second protective film made of substantially the same material as the first protective film;
- and
- wherein only one substrate exists in the disk structure.
6 more elements
An optical disk consisting essentially of
- a) only one transparent plastic substrate,
- b) a recording film formed on one side surface of said substrate,
- c) a first protective film covering said recording film, and
- d) a moisture-impermeable film formed on the other side of said substrate,
- wherein the moisture-impermeable film is further covered with a second protective film made of substantially the same material as that of the first protective film,
- wherein the first and second protective films are a UV curing urethane acrylate resin containing a transparent conductive substance in powder form.
3 more elements
An optical disk consisting essentially of:
- only one transparent plastic substrate;
- a recording film formed on one side surface of said substrate;
- a first protective film covering said recording film, and
- a moisture-impermeable film formed on the other side of said substrate,
- wherein the moisture-impermeable film is further covered with a second protective film, and the first and the second protective films have substantially the same moisture absorption properties.
2 more elements
Dependencies are inferred from the claim text.