EP0318794A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Stretched styrene-based resin moldings and a process for production thereof
Assignee: Idemitsu Kosan Co Ltd
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Filing: 1988-11-22
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Granted: —
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Expires: 2008-11-22
Abstract
Abstract Stretched moldings (e.g., stretched films, sheets or bottles) of styrene-based resins (e.g., polystyrene) having mainly syndiotactic configuration and a weight average molecular weight of at least 50,000, and a process for the production thereof are disclosed. The stretched moldings are obtained by uniaxially stretching the styrene-based resins at a draw ratio of at least 2 times, or biaxially stretching at a draw ratio of at least 1.2 times in each direction. The stretched moldings are excellent in heat resistance, chemical resistance, solvent resistance, electric insulating properties, mechanical strength and so forth, and thus can be used as food wrapping materials, housing materials for electric or electronic parts, and so forth.
Inventors
- 👤 Akikazu Nakano
- 👤 Toshihiro Furusawa
- 👤 Toshikazu Ijitsu
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-29 19:34
CPC Classifications
B; B29; B29C; B29C55/00; B29C55/005; B29C55/02; B29C55/10; B29C55/12; B29D; B29D7/00; B29D7/01; C; C08; C08J; C08J5/00; C08J5/18; B29K; B29K2025/00; B29L; B29L2007/00; C08J2325/00; C08J2325/02; C08J2325/04
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
46 words
A stretched styrene-based resin molding as obtained by subjecting a styrene-based polymer having mainly syndiotactic configuration and a weight average molecular weight of at least 50,000 to uniaxial stretching of at least two times or to biaxial stretching of at least 1.2 times in each direction.
Claim 2
Dependent Claim
46 words
A stretched styrene-based resin molding as obtained by subjecting a styrene-based polymer having mainly syndiotactic configuration and a weight average molecular weight of at least 50,000 to uniaxial stretching of at least two times or to biaxial stretching of at least 1.2 times in each direction.
Claim 3
Dependent Claim
21 words
The molding as claimed in Claim 1, having heat resistance and such transparency that the haze is not more than 30%.
Claim 4
Dependent Claim
24 words
The molding as claimed in Claim 1, having such electric insulating properties that the breakdown voltage at 25 °C is at least 30 kV/mm.
Claim 5
Dependent Claim
48 words
A process for producing a stretched styrene-based resin molding which comprises subjecting a styrene-based resin having mainly syndiotactic configuration and a weight average molecular weight of at least 50,000 to uniaxial stretching of at least two times or biaxial stretching of at least 1.2 times in each direction.
Claim 6
Dependent Claim
48 words
A process for producing a stretched styrene-based resin molding which comprises subjecting a styrene-based resin having mainly syndiotactic configuration and a weight average molecular weight of at least 50,000 to uniaxial stretching of at least two times or biaxial stretching of at least 1.2 times in each direction.
Claim 7
Dependent Claim
67 words
A process for producing a stretched styrene-based resin molding which comprises heat melting a styrene-based resin having mainly syndiotactic configuration and a weight average molecular weight of at least 50,000, quenching the molten resin, and then subjecting the quenched resin to uniaxial stretching at a draw ratio of at least two times or biaxial stretching at a draw ratio of at least 1.2 times in each direction.
Claim 8
Dependent Claim
67 words
A process for producing a stretched styrene-based resin molding which comprises heat melting a styrene-based resin having mainly syndiotactic configuration and a weight average molecular weight of at least 50,000, quenching the molten resin, and then subjecting the quenched resin to uniaxial stretching at a draw ratio of at least two times or biaxial stretching at a draw ratio of at least 1.2 times in each direction.
Claim 9
Dependent Claim
15 words
The process as claimed in Claim 5, wherein quenching rate is from 200 to 3°C/sec.
Claim 10
Dependent Claim
39 words
A stretched styrene-based resin molding as obtained by subjecting the stretched styrene-based resin molding of Claim 1 to annealing at a temperature of 10°C higher than the glass transition temperature to a temperature of 5°C lower than melting point.
Claim 11
Dependent Claim
19 words
The stretched styrene-based resin molding as claimed in Claim 7 wherein the temperature of annealing is 120°C to 250°C.
References Cited (Backward Citations)
No citation records indexed.
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