Mitsui Toatsu Chemicals, Incorporated

Yamamoto Chemicals, Inc.

Shigeru Takahara

Sumio Hirose

Tadashi Koike

Hiroshi Ozawa

Shin Aihara

Kenji Abe

Yoichi Hosono

Keiji Ueno

Tomoyoshi Sasakawa

Hiroshi Sukawa

Disclosed are optical recording media, each of which is composed of a substrate and a recording layer formed on the substrate. The recording layer includes an organic-dye-containing layer and an organopolysiloxane resin layer formed by the condensation of a trifunctional silane represented by R.sup.1 Si(OR.sup.2).sub.3-n (X).sub.n and a tetrafunctional silane represented by Si(OR.sup.3).sub.4-m (X).sub.m, wherein R.sup.1, R.sup.2 and R.sup.3 individually represent an alkyl or aryl group, X a hydroxyl group or a halogen atom, and n and m 0, 1, 2 or 3 and 0, 1, 2, 3 or 4, respectively.

Optical recording media

Disclosed are optical recording media, each of which is composed of a substrate and a recording layer formed on the substrate. The recording layer includes an organic-dye-containing layer and an organopolysiloxane resin layer formed by the condensation of a trifunctional silane represented by R.sup.1 Si(Or.sup.2).sub.3-n (X).sub.n and a tetrafunctional silane represented by Si(OR.sup.3).sub.4-m (X).sub.m, wherein R.sup.1, R.sup.2 and R.sup.3 individually represent an alkyl or aryl group, X a hydroxyl group or a halogen atom, and n and m 0, 1, 2 or 3 and 0, 1, 2, 3 or 4, respectively.

This invention relates to an optical recording medium characterized by high sensitivity, high stability, etc, and a process for making the optical recording medium. Specifically, the present invention provides an optical recording medium composed of a transparent substrate having prepits and/or pregrooves for system control signals and first and second recording layers formed thereon in order, the both layers having individually a specific reflectance, transmittance and absorbance. To the optical recording medium, a laser beam is irradiated on the transparent substrate side to record or read out information and, by detecting the variation of the amount of light as a sum of the reflected light from the boundary between the first recording layer and the substrate and the reflected light from the boundary between the second recording layer and the air, the system control signals are primarily obtained from the prepits and/or pregrooves. Regarding the two recording layers, the first recording layer contains an organic dye having a transmittance of 10-50% and an absorbance of 40% or more against the wavelength of a laser beam used for writing while the second recording layer contains an organic dye having an absorbance of 20% or less and a reflectance of 25% or more at the air boundary at the wavelength region of the laser beam. The optical recording medium can be made in accordance with the process of the present invention wherein (a) a transparent substrate having prepits and/or pregrooves for system control signals is provided, (b) two kinds of solution are prepared by allowing two organic dyes each soluble exclusively in either a low-polar solvent or else a high-polar solvent to dissolve in the respective counterpart solvent, and (c) the two kinds of dye solution are applied on the transparent substrate in series to form the first recording layer and the second recording layer.

Optical recording medium and process for fabricating the same

An optical recording medium comprising practically a naphthalocyanine dye represented by the following general formula (I): ##STR1## wherein M means a metal, metal oxide or metal halide, and --OR.sub.1, --OR.sub.2, --OR.sub.3 and --OR.sub.4 are the same or different and denote ether groups respectively having R.sub.1, R.sub.2, R.sub.3 and R.sub.4 each of which is a saturated or unsaturated hydrocarbon group having 4-12 carbon atoms.

Optical recording medium

Optical recording medium having a reflective recording layer including a

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Kanagawa, Japan

Shigeru Takahara