EP0071981A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Foamed molded articles of polypropylene resin
Assignee: JSP Corp
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Filing: 1982-08-04
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Granted: —
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Expires: 2002-08-04
Abstract
Abstract A foamed and molded article of a polypropylene resin characterized by having a latent heat of crystallization of from 9 to 28 cal/g, a density of from 0.026 to 0.060 g/cm 3 and such a cellular structure that the number of cells per mm 2 of its cross section is not more than 300, said article being obtained by filling preliminarily-foamed particles of the polypropylene resin in a mold capable of enclosing the particles but allowing escape of gases therefrom, and heating said particles to expand them to the configuration of the mold.
Inventors
- 👤 Kuninori Hirosawa
- 👤 Hideki Kuwabara
- 👤 Sumio Shimada
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-26 01:06
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/22; C08J9/228; C08J9/232; C08J2323/00; C08J2323/02; C08J2323/10
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
92 words
A foamed and molded article of a polypropylene resin characterized by having a latent heat of crystallization of from 9 to 28 cal/g, a density of from 0.026 to 0.060 g/cm and such a cellular structure that the number of cells per mm 2 of its cross section is not more than 300, said article being obtained by filling preliminarily-foamed particles of the polypropylene resin in a mold capable of enclosing the particles but allowing escape of gases therefrom, and heating said particles to expand them to the configuration of the mold.
Claim 2
Dependent Claim
92 words
A foamed and molded article of a polypropylene resin characterized by having a latent heat of crystallization of from 9 to 28 cal/g, a density of from 0.026 to 0.060 g/cm and such a cellular structure that the number of cells per mm 2 of its cross section is not more than 300, said article being obtained by filling preliminarily-foamed particles of the polypropylene resin in a mold capable of enclosing the particles but allowing escape of gases therefrom, and heating said particles to expand them to the configuration of the mold.
Claim 3
Dependent Claim
48 words
The article of claim 1 which has a latent heat of crystallization of from 9 to 25 cal/g, a density of 0.026 to 0.060 g/cm , and such a cellular structure that the number of cells per mm 2 of its cross section is not more than 150.
Claim 4
Dependent Claim
62 words
The article of claim 1 wherein the polypropylene resin is a homopolymer of propylene, an ethylene/propylene copolymer, a mixture of the homopolymer of propylene and the ethylene/propylene copolymer, a mixture of the ethylene/propylene copolymer and low-density polyethylene, a mixture of the ethylene/propylene copolymer and an ethylene/vinyl acetate copolymer, or a mixture of the ethylene/propylene copolymer, low-density polyethylene and the ethylene/vinyl acetate copolymer.
Claim 5
Dependent Claim
22 words
The article of claim 3 wherein the ethylene/ propylene copolymer is a block copolymer, a random copolymer or a mixture of these.
References Cited (Backward Citations)
AT274392B
Cited
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