EP0503097A1
Expired / Lapsed
EP
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Optical sheet material
Assignee: Toray Industries Inc
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Filing: 1991-10-03
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Granted: —
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Expires: 2011-10-03
Abstract
Abstract An optical sheet material preferably used for the optical filter of display units, the substrate of liquid crystal display elements, the substrate of optical recording disks, and optical lenses; having the glass transition temperature and softening point of 130°C or higher, the flexural elastic modulus of 50 to 1,000 kgf/mm², the birefringence index of 30 nm or less, the yellowness index of 5 or less, the specific gravity of 1.5 or less, the deflection of 10 mm or less in a load-deflection test, and the thickness of 0.3 to 0.7 mm.
Inventors
- 👤 Takashi 1300-134 Oaza Minamizakura Taniguchi
- 👤 Kazuo 560 Ishido Gamou-Cho Tanaka
- 👤 Shinya Adachi
- 👤 Masaki Maekawa
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 12:37
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; G11B7/241; G11B7/252; G11B7/253; G11B7/2533; C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/12; C08L; C08L79/00; C08L79/04; C08L79/08; C08L79/085; G02; G02B; G02B1/00; G02B1/04; G02B1/041; G11B7/2536
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
81 words
A sheetlike article for optical applications, formed of a resin having both a glass transition point and a softening point higher than 130°C, a modulus of elasticity when bent of more than 50 kgf/mm² and not more than 1,000 kgf/mm², a double refraction index of not greater than 30 nm, a yellow color index of not higher than 5, a specific gravity of not more than 1.5, and a thickness of more than 0.3 mm and not more than 0.7 mm.
Claim 2
Dependent Claim
52 words
A sheetlike article for optical applications, formed of a resin having both a glass transition point and a softening point higher than 130°C, an amount of deflection of not more than 10 mm in a load flexure test, and a thickness of more than 0.3 mm and not more than 0.7 mm.
Claim 3
Dependent Claim
53 words
A sheetlike article for optical applications, formed of a resin having both a glass transition point and a softening point higher than 130°C, an amount of deflection of not more than 20 mm in a cantilever test at 100°C, and a thickness of more than 0.3 mm and not more than 0.7 mm.
Claim 4
Dependent Claim
26 words
An optical sheetlike article according to claim 1, 2 or 3, wherein both the glass transition point and the softening temperature are not lower than 170°C.
Claim 5
Dependent Claim
35 words
An optical sheetlike article according to claim 2 or 3, wherein the specific gravity is not less than 0.8 and not more than 1.5 and the double refraction index is not more than 30 nm.
Claim 6
Dependent Claim
19 words
An optical sheetlike article according to claim 1, 2 or 3, wherein the resin is produced by cast polymerization.
Claim 7
Dependent Claim
19 words
An optical sheetlike article according to claim 1, 2 or 3, wherein the resin is a three-dimensionally cross-linked resin.
Claim 8
Dependent Claim
80 words
An optical sheetlike article according to claim 1, 2, 3 or 4, wherein the resin is a copolymer containing a monomer represented by the general formula (1) in an amount of not less than 20% by weight and not more than 98% by weight. wherein R¹ and R² each are selected from a hydrogen atom, methyl group and ethyl group, and R³ is selected from alkyl groups having 1 to 20 carbon atoms, aryl groups, aralkyl groups and cycloalkyl groups.
Claim 9
Dependent Claim
106 words
An optical sheetlike article according to claim 1, 2, 3 or 4, wherein the resin is a copolymer containing a polyfunctional maleimide represented by the general formula (2) in an amount of not less than 1% by weight and not more than 40% by weight. wherein R⁴ and R⁵ each are selected from a hydrogen atom, methyl group and ethyl group, R⁶ stands for an organic group of the valency of n having 1 to 40 carbon atoms, which organic groups are severally bound with the nitrogen atoms of maleimide through the N-C link, and n stands for an integer of from 2 to 10 inclusive.
Claim 10
Dependent Claim
50 words
An optical sheetlike article according to claim 6, 7, 8 or 9, wherein the resin is a copolymer obtained by polymerizing a composition containing a polyfunctional monomer containing at least two unsaturated groups in an amount of not less than 2% by weight and not more than 80% by weight.
Claim 11
Dependent Claim
21 words
An optical sheetlike article according to claim 10, wherein said polyfunctional monomer containing at least two unsaturated groups is divinyl benzene.
References Cited (Backward Citations)
No citation records indexed.
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