Mitsui Toatsu Chemicals, Incorporated

Yamamoto Chemicals, Inc.

Mitsui Chemicals, Inc.

Sumio Hirose

Tadashi Koike

Hideki Umehara

Shin Aihara

Hiroshi Ozawa

Kenji Abe

Yoichi Hosono

Shigeru Takahara

Takeshi Tsuda

Yuji Inatomi

Tomoyoshi Sasakawa

Tadahiko Mizukuki

Nobuhisa Kitagawa

Keiji Ueno

Yuko Suzuki

Shinichi Murakami

Masatoshi Yanagimachi

Yoshiteru Taniguchi

Kouichi Yabuuchi

Kouhei Shizuka

Keisuke Takuma

Tsutami Misawa

Tadashi Kitamura

Akio Matsuyama

Katsuru Matsumoto

Hiroshi Mase

Hiroshi Sukawa

Isao Naruse

Takayuki Sanada

A lithographic printing original plate, a lithographic printing plate using the lithographic printing original plate and a process for producing the lithographic printing plate are disclosed. The lithographic printing original plate has, on a substrate, a photosensitive layer made of a crosslinked polymer comprising a hydrophilic polymer, a crosslinking agent and a light absorbing compound or comprising a hydrophilic polymer, a crosslinking agent, a light absorbing compound and a hydrophobic polymer, and has properties that the photosensitive layer is changed from ink-repellent to ink-receptive by irradiation with a light.

Lithographic printing plate

An optical information recording medium is here disclosed which comprises a transparent substrate, a recording layer comprising an organic dyestuff on which information can be written by a laser beam, a reflective layer and a protective layer formed in this order on the substrate, the aforesaid optical information recording medium being characterized by containing a pit-edge control agent for the formation of recording pits, particularly a dyestuff thermal decomposition accelerator in the recording layer. By the addition of the pit-edge control agent, deviation properties and jitter properties can be remarkably improved, whereby a CD-R medium having a low error rate and good recording properties can be provided. In consequence, stable compatibility with a commercial CD player can be secured.

Optical information recording medium and composition for optical information recording film

An optical information recording medium is here disclosed which comprises a transparent substrate, a recording layer comprising an organic dyestuff on which information can be written by a laser beam, a reflective layer and a protective layer formed in this order on the substrate, the aforesaid optical information recording medium being characterized by containing a pit.multidot.edge control agent for the formation of recording pits, particularly a dyestuff thermal decomposition accelerator in the recording layer. By the addition of the pit.multidot.edge control agent, deviation properties and jitter properties can be remarkably improved, whereby a CD-R medium having a low error rate and good recording properties can be provided. In consequence, stable compatibility with a commercial CD player can be secured.

Optical information recording medium and composition for optical

Provided is an optical recording medium in which per-pits in a ROM area have a depth of 250 nm or more and 350 nm or less; pre-grooves between the pre-pits have a depth of 30 nm or more and 170 nm or less; wobbling tracks have an amplitude of 25 nm or more and 110 nm or less; the product of the depth of the pre-grooves between the pits and the wobble amplitude of the track is 3100 or more; and pre-grooves in a RAM area have a depth of 130 nm or more and 250 nm or less. The optical recording medium is a hybrid disk having such good signal characteristics as satisfying the Orange Book standards.

Optical recording media

An optical recording medium has a recording layer, a reflective layer and a protective layer, all of which are arranged on a substrate. The recording layer contains a porphyrin compound represented by the following formula (1): ##STR1## wherein R.sub.1 to R.sub.8 independently represent a hydrogen atom, an alkyl group, an alkoxy group, an alkylcarbonyl group, an alkoxycarbonyl group, an alkylthio group or a halogen atom, R.sub.9 to R.sub.12 independently represent a hydrogen atom or an alkyl group, and X.sup.- represents an anion.

There is provided with an optical recording medium comprising at least a dye-containing recording layer and a reflective layer laminated on a transparent substrate in this order which has a reflectance of 65% or higher, measured through the substrate, to a light beam having a selected wavelength (.lambda.1) of from 770 to 830 nm and has a reflectance of 15% or higher to a light beam having a selected wavelength (.lambda.2) of from 630 to 690 nm and which is recordable and reproducible with a laser beam having the wavelength of .lambda.1 and being reproducible with a laser beam having the wavelength of .lambda.2. In addition, the recording layer has a dye A having the absorption maximum at the wavelength shorter than 630 nm mixed with a dye B having the absorption maximum at the wavelength of from 630 to 900 nm. Alternatively, an interference layer is provided along with the recording and reflective layers. The recording layer is based on a phthalocyanine dye while the interference layer is based on an inorganic dielectric, a polymer, or an azo dye. The requirements for the interference layer are also provided.

Optical recording media and a method of recording and reproducing

An optical recording medium comprising a transparent substrate; a recording layer on the transparent substrate; a metal reflective layer; and one or more protective layers. These layers are laminated successively on the transparent substrate. The outermost protective layer is formed of an ultraviolet curable resin containing an organic filler and/or an inorganic filler having water absorbency and/or oil absorbency. The protective layer has a printable surface permitting writing characters with writing instruments or ink jet printers.

Optical recording medium

An optical information recording medium is here disclosed which comprises a transparent substrate, a recording layer comprising an organic dyestuff on which information can be written by a laser beam, a reflective layer and a protective layer formed in this order on the substrate, the aforesaid optical information recording medium being characterized by containing a pit.edge control agent for the formation of recording pits, particularly a dyestuff thermal decomposition accelerator in the recording layer. By the addition of the pit.edge control agent, deviation properties and jitter properties can be remarkably improved, whereby a CD-R medium having a low error rate and good recording properties can be provided. In consequence, stable compatibility with a commercial CD player can be secured.

An optical recording medium comprises a substrate, a recording layer overlying the substrate in a manner such that it is not present at the inner and outer peripheral portions of the substrate, a metal reflective layer overlying the recording layer in a manner such that the inner periphery of the metal reflective layer is coterminous with that of the recording layer while the outer peripheral portion of the reflective layer extends over the outer perphery of the recording layer, and a protective layer wholly covering the metal reflective layer extending over the recording layer, both at the inner and outer peripheral portions. The optical recording medium exhibits an excellent adhesion strength of the protective layer even when stood under high humidity and high temperature conditions for a long period of time, and the protective layer is not peeled off when subjected to a tape peeling test.

Optical recording medium and production thereof

An optical recording medium comprises a substrate, a recording layer overlying the substrate in a manner such that it is not present at the inner and outer peripheral portions of the substrate, a metal reflective layer overlying the recording layer in a manner such that the inner periphery of the metal reflective layer is coterminous with that of the recording layer while the outer peripheral portion of the reflective layer extends over the outer periphery of the recording layer, and a protective layer wholly covering the metal reflective layer extending over the recording layer, both at the inner and outer peripheral portions. The optical recording medium exhibits an excellent adhesion strength of the protective layer even when stood under high humidity and high temperature conditions for a long period of time, and the protective layer is not peeled off when subjected to a tape peeling test.

An optical recording medium comprises a transparent substrate, a recording layer containing at least one organic dye overlying the substrate, a metallic layer directly contacting and overlying the recording layer, a protective layer comprising at least one layer directly contacting and overlying the metal layer, a layered print portion comprising at least one layer directly contacting and overlying the protective layer, and said protective layer and said print portion satisfying the following relationship:

An optical recording medium for pit length recording with excellent error rate and jitter value which has a transparent injection molded resin substrate, a recording layer containing a phthalocyanine dye of formula (1) overlying the substrate and a covering layer overlying the recording layer. Also, a method of optical recording by pit length recording with a focused laser beam using an optical recording medium as described above.

Optical recording medium and recording method

An optical recording medium of a single plate type comprises a substrate having a groove, a recording layer containing a dye overlying the substrate, a reflective layer overlying the recording layer and a protective layer overlying the reflective layer, wherein the recording layer is formed by a spin-coating method and the dimension of the groove varies from the center portion of the substrate toward the outer periphery thereof.

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.

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.

Growing community of inventors

Yokohama, Japan

Sumio Hirose