Patent EP0405843A2 successfully refreshed from Google Patents.
EP0405843A2
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EP
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Molding material
Assignee: Zeon Corp
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Filing: 1990-06-21
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Granted: —
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Expires: 2010-06-21
Abstract
Abstract A molding material suitable as an optical material and an optical recording medium formed of the molding material are disclosed. The molding material comprises a hydrogenated product of a polymer formed by ring-opening polymerization of a norbornene-type monomer, the hydrogenated product having a number average molecular weight (Mn) of 20,000 to 50,000, a weight average molecular weight (Mw) of 40,000 to 80,000 and a molecular distribution (Mw/Mn) of not more than 2.5 and having a volatile content of not more than 0.3% by weight.
Inventors
- 👤 Yoshikatsu C/O Nippon Zeon Co. Ltd. Nishi
- 👤 Masayoshi Oshima
- 👤 Tadao Natsuume
- 👤 Teiji Kohara
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-27 05:18
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G61/00; C08G61/02; C08G61/04; C08G61/06; C08G61/08; G; G11; G11B; G11B7/00; G11B7/24; G11B7/241; G11B7/252; G11B7/253; G11B7/26; G11B7/263
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
74 words
A molding material comprising a hydrogenated product of a polymer formed by ring-opening polymerization of a norbornene-type monomer, the hydrogenated product having a number average molecular weight (Mn), measured by high-performance liquid chromatography, of 20,000 to 50,000, a weight average molecular weight (Mw), measured by the same, of 40,000 to 80,000 and a molecular weight distribution (Mw/Mn) of not more than 2.5 and having a volatile content of not more than 0.3% by weight.
Claim 2
Dependent Claim
74 words
A molding material comprising a hydrogenated product of a polymer formed by ring-opening polymerization of a norbornene-type monomer, the hydrogenated product having a number average molecular weight (Mn), measured by high-performance liquid chromatography, of 20,000 to 50,000, a weight average molecular weight (Mw), measured by the same, of 40,000 to 80,000 and a molecular weight distribution (Mw/Mn) of not more than 2.5 and having a volatile content of not more than 0.3% by weight.
Claim 3
Dependent Claim
22 words
A molding material according to Claim 1, wherein the hydrogenated product has a glass transition point (Tg) of not less than 100°C.
Claim 4
Dependent Claim
20 words
A molding material according to Claim 2, wherein the hydrogenated product has a hydrogenation ratio of not less than 90%.
Claim 5
Dependent Claim
22 words
A molding material according to Claim 2, wherein the hydrogenated product has a volatile content of not more than 0.2% by weight.
Claim 6
Dependent Claim
31 words
A molding material according to Claim 2, wherein the hydrogenated product has a hydrogenation ratio of not less than 95% and a volatile content of not more than 0.1% by weight.
Claim 7
Dependent Claim
21 words
A molding material according to Claim 5, wherein the hydrogenated product has a glass transition point (Tg) of 120 to 200°C.
Claim 8
Dependent Claim
22 words
A molding material according to Claim 1, wherein the norbornene-type monomer is comprised of a tetracyclic norbornene-type compound as a main component.
Claim 9
Dependent Claim
24 words
A molding material according to Claim 1, wherein the norbornene-type monomer is a compound having a substituent of a lower alkyl or alkylidene group.
Claim 10
Dependent Claim
17 words
A molding material according to Claim 8, wherein the substituent is a C₂-C₃ alkyl or alkylidene group.
Claim 11
Dependent Claim
45 words
A molding material according to any one of Claim 1 to 9, which further comprises 0.01 to 5 parts by weight, per 100 parts by weight of the hydrogenated product, of an antioxidant having a vapor pressure, at 20°C, of not more than 10⁻⁶ Pa.
Claim 12
Dependent Claim
20 words
A molding material according to Claim 10, wherein the antioxidant has a vapor pressure of not more than 10⁻⁸ Pa.
Claim 13
Dependent Claim
22 words
A molding material according to Claim 11, wherein the antioxidant is a hindered phenol type, aminophenol type, hydroquinone type, or phosphite type.
Claim 14
Dependent Claim
18 words
An optical disk substrate formed of the molding material recited in any one of Claims 1 to 12.
Claim 15
Dependent Claim
33 words
An optical recording medium produced by forming an optically writable and/or readable recording thin film on a transparent substrate formed of the molding material recited in any one of Claims 1 to 12.
References Cited (Backward Citations)
No citation records indexed.
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