Ricoh Company, Ltd.

Bridgestone Corporation

Nippon Unicar Company Limited

Yamada Chemical Co., Ltd.

Yutaka Ueda

Tsutomu Sato

Michiharu Abe

Toru Yashiro

Masaakira Umehara

Hideaki Oba

Tetsu Yamamuro

Eiji Noda

Noboru Yamaguchi

Takao Aizawa

Kazuyuki Isobe

Yasuo Sawada

Makoto Kunikane

Seiko Kobayashi

Tetsuo Hosokawa

Hitoshi Funakoshi

An optical recording medium has a substrate, and a light absorbing layer serving as a recording layer formed on the substrate. The light absorbing layer contains a metallo-phthalocyanine compound of formula (I): ##STR1## wherein M is Mn, Fe, Co, Zn or Cd; and either A.sup.1 or A.sup.2, either A.sup.3 or A.sup.4, either A.sup.5 or A.sup.6, and either A.sup.7 or A.sup.8 is --OR group or --SR group in which R is an aliphatic, aromatic or alicyclic hydrocarbon group, and the other is hydrogen; and a nitrogen-containing compound selected from the group consisting of an amino compound, an imino compound and an azo compound, each of which may have a substituent or form a ring.

Optical recording medium and method of producing the same

An optical information recording medium including a ROM area and a recordable area is composed of a light-transmitting substrate with prepits and/or guide grooves formed on the surface thereof, a light absorption layer serving as a recording layer which is composed of a dye as the main component overlaid on the light-transmitting substrate, and a light reflection layer which is composed of metallic film overlaid on the light absorption layer. The light absorption layer of this optical information recording medium is formed on the substrate by coating a solution composed of a dye and a solvent of a mixture of a fluoridated alcohol of formula (I) and an alcohol of formula (II):

Optical information recording medium

An optical information recording medium is composed of a substrate and a recording layer which is formed on the substrate and made of a composition comprising at least gold and sulfur, with the gold content being 50 atomic percent or more in the composition.

An optical recording medium is composed of a substrate, and a recording layer formed thereon, which is made of (a) a first recording layer which contains a light-absorbing organic compound and can be deformed upon irradiation of light thereto, and (b) a second recording layer which includes a sulfide containing antimony in an amount of 50 atm % or more, and can be deformed in accordance with the deformation of the first recording layer.

Optical recording medium

An optical recording medium is composed of a substrate, a recording layer containing an inorganic material which includes as the main component a sulfide of at least one element selected from the group consisting of the elements of IIb, IIIb, IVb, Vb, and VIb groups, which is formed on the substrate, with a complex index of refraction of (n-ik), where n.gtoreq.1.8, and k.ltoreq.0.3, and a reflection layer formed on the recording layer. In this invention, an intermediate layer can be interposed either between the substrate and the recording layer, or between the recording layer and the reflection layer.

An optical recording medium comprising a pair of concentrically-positioned disk-shaped polycarbonate substrates with a recording layer on a single surface of at least one of these substrates, wherein the substratcs are formed into a sealed configuration with the recording layer on the inside, either with or without an inner peripheral spacer and an outer peripheral spacer, using an adhesive which comprises a compound of formula (I), a compound of formula (II)-A or (II)-B, and a compound of formula (III) as specified in the specification.

An optical information recording medium comprising a substrate and a recording layer, formed on the substrate, which comprises a composition of antimony, sulfur, and one element selected from the group consisting of the elements belonging to group IIB and group IVA of the periodic table.

A composition for producing a water-proof sheet comprising 100 weight parts of a linear ethylene-alpha-olefin copolymer having a density equal to or less than 0.910 g/ml, and 10-200 weight parts of asphalt. Water proof sheets produced from the composition are also included in the invention. In a preferred mode, the composition also includes an organic peroxide.

Composition for water proof sheets

An information recording medium of an air-sandwich sealed type is disclosed, which comprises a pair of disk-shaped substrate to form an inner space therebetween; an inner circumferential spacer and an outer circumferential spacer interposed between the pair of disk-shaped substrates; and a recording layer formed on the inner surface of at least one of the disk-shaped substrates, with an adhesive agent being applied to the surface of at least the inner circumferential spacer or the outer circumferential spacer in the form of a plurality of concentric adhesive layers, each of the concentric adhesive layers having at least one cut-away portion to which the adhesive agent is not applied to form a vent and an air passage between the surface of the inner circumferential space or the outer circumferential spacer and any of the substrates, the vent and the air passage capable of allowing the air to pass from the inner inner space formed by the disk-shaped substrates to the outside and vice versa, and the cut-away portions of the adhesive layers being shifted in position from each other.

Information recording medium with concentric spacers and cut-away

An optical information recording medium is disclosed which comprises a pair of substrates at least one of which has a recording layer on one side thereof and which are placed opposingly to each other so that said recording layer is positioned on the inside and are bonded to each other by adhesive layer(s) with or without spacer(s) therebetween to form a sealed structure, wherein said adhesive layer is composed of a cured adhesive material formed from (a) an epoxy resin, (b) a photolyzable organosilicon compound and (c) an aluminum complex compound, said photolyzable organosilicon compound being a silicon compound having at least one phenyl group which has at least one fluorine atom and at least one o-nitrobenzyloxy group which may have a substituent. The said photolyzable oganosilicon compound may be replaced by a mixture of (b-1) a silicon compound having at least one phenyl group having at least one fluorine atom and at least one o-nitrobenzyloxy group which may have a substituent, and (b-2) a silicon compound having at least one phenyl group having no substituents and at least one o-nitrobenzyloxy group which may have a substituent.

This invention relate to an optical information recording medium, characterized by having an organic thin film recording layer containing at least one of compounds expressed by the general formula (I), (II), (III) and (IV): ##STR1## (wherein in the above formulas, A, B, D and E represent a substituted or non-substituted aryl group; R.sub.1 to R.sub.8 may be the same or different and represent hydrogen atom, halogen atom or alkyl group; Y represents a divalent residue having atomic groups necessary for forming a five-membered ring or six-membered ring; m, n and l represents 0, 1 or 2; ans X.sup.- represents an acid anion); ##STR2## (wherein in the above formulas, A' represents a heterocyclic ring selected from the group of thiazole, oxazole, pyrrole, 3,3-dialkyl indolenine, imidazole, pyridine and quinoline and said heterocyclic ring may be condensed with a benzen ring or naphthalene ring, the aromatic ring of which may have a substituent; D' and E' may be the same or different and represent a substituted or non-substituted aromatic ring or D' and E' may get together to form an aromatic ring or heterocyclic ring; X represents an anion; l represents 0, 1 or 2 and m and n represnt 0, 1, 2 or 3; R.sub.9 represents hydrogen, alkyl group, amino group or halogen atom; and Y represents atomic groups necessary for forming a substituted or non-substituted five-membered ring or six-membered ring).

Optical information recording element

An optical information recording medium is disclosed, which comprises a pair of disc-shaped substrates, at least one of the substrates having a recording layer comprising an organic dye compound on one side thereof, which are disposed so as to face each other, with the recording layer positioned therebetween, with or without a space between the two substrates, by sealing with an adhesive agent comprising an alicyclic epoxy resin component having general formula ##STR1## where R.sup.1 .about.R.sup.9 each represent hydrogen, an alkyl group having 1 to 4 carbon atoms, or halogen; and R represents (CH.sub.2).sub.n, where n is an integer of 1 to 4, ##STR2## and a composite catalyst comprising a photo-decomposition organic silicon compound and a metal complex.

An optical information recording medium comprises a pair of substrates, with a recording layer comprising an organic dye being formed on one side of at least one substrate, fixed to each other through or without through a spacer and by an adhesive agent, in such a manner that the recording layer comes between the substrates, the adhesive agent comprising:

This invention provides an optical information recording medium that has, on a substrate, a recording layer containing a cyanine dye represented by the general formula: ##STR1## (wherein, R.sub.1, R.sub.2 and R.sub.3 may be the same or different and each stands for a substituted or unsubstituted alkyl group; X stands for a perhalogenate ion, a toluenesulfonate ion or an alkylsulfate ion; n stands for an integrer of 0 or 1-3; a first halogen atom is present in at least one of each 4, 6 and 7-positions of the indole and indolenine rings; a second halogen atom may be present in each 5-position of said rings; and at lest one group consisting of alkyl, alkoxy, hydroxy, carboxy, allyl and alkylcarbonyl may be present in at least one of each 4, 5, 6 and 7-positions of said rings.) and, if necessary, a transition metal complex or a salt of said complex with a cation.

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Yokohama, Japan

Yutaka Ueda