Optical recording medium
OwnerHiroshi Ozawa, Yoichi Hosono +3inventors
InventorsHiroshi Ozawa, Yoichi Hosono, Sumio Hirose, Katsuyoshi Sasagawa, Masao Imai
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Abstract
Disclosed herein is an optical recording medium which includes a recording layer composed of (a) an organometallic complex having an absorption maximum in the wavelength range of 600-1200 nm, (b) a resinous binder and (c) a sensitizer capable of generating radicals upon exposure to ultraviolet rays. The recording of information on the recording layer is effected with ease by exposure to ultraviolet rays. The reproduction of recorded information is effected by a laser beam having an oscillatory wavelength in the visible or near infrared wavelength range.
Claims11
A method of optically recording information which comprises providing an optical recording medium having a recording layer composed of:
- (a) an organometallic complex having an absorption maximum in the wavelength range of 600-1200 nm and being selected from the group consisting of:
- (i) aromatic diamine metal complexes of the formula ##STR6## wherein R is a hydrogen or a halogen atom or an alkyl or nitro group, n is an integer of 1 to 4 and M is a nickel, palladium or platinum atom;
- (ii) aromatic dithiol metal complexes of the formula ##STR7## wherein Z is a hydrogen or a halogen atom or an alkyl group, n is an integer of 1 to 4, M is a nickel, palladium or platinum atom and A is a quaternary ammonium group;
- (iii) aliphatic diamine metal complexes of the formula ##STR8## wherein Y is a hydrogen atom or an alkyl or phenyl group and M is a nickel, palladium or platinum atom;
- (iv) aliphatic dithiol metal complexes of the formula ##STR9## wherein E is a hydrogen atom or an alkyl or phenyl group and M is a nickel, palladium or platinum atom;
- and
- (v) mercaptophenol metal complexes of the formulas ##STR10## wherein G is a hydrogen or a halogen atom or an alkyl group, M is a nickel, palladium or platinum atom and A is a quaternary ammonium group;
- (b) a resinous binder;
- and
- (c) a sensitizer capable of generating radicals upon exposure to an ultraviolet ray,
- and exposing said recording layer to an ultraviolet ray in the wavelength range of 200-400 nm to diminish the absorption of said metal complexes in the wavelength range of 600-1200 nm at the exposed portion of said layer compared with the unexposed portion thereof, thereby recording information on said recording layer in a substantially pitless form.
Dependencies are inferred from the claim text.