USPatentGranted

Polypropylene stretched film

Granted 16 Jul 1991 · no office action yet

Current assignee: Sumitomo Chemical Company, Limited · originally Sumitomo Chemical

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Inventors: Seiichiro Ima, Tadatoshi Ogawa, Kazuki Wakamatsu · Examiner: Carman J. Seccuro

Application
433124
filed 8 Nov 1989
Publication
Not published
not published
Patent· this page
US 5,032,645
granted 16 Jul 1991

Life of the patent

3 dated events
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Abstract

The polypropylene stretched film of the present invention is prepared by stretching a composition comprising a crystalline propylene polymer and 0.1 ppm by weight to 10% by weight of a nucleating agent, the composition having a melting point of 160.degree. C. or more, a crystallization temperature of 128.degree. C. or more and a 20.degree. C. xylene soluble portion of 3.0% by weight or less. The film has a high rigidity and a beautiful appearance as well as the characteristic properties inherent to crystalline propylene polymers. The film can be suitably used for food packaging and textile packaging.

Claims

1 · 1 independent · depth 1
1 granted claims

Classifications

4 codes
USPC · US Patent Classification
525/216525/88525/95525/297

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Pendency
1.7 y
615 days filing → grant
Office actions
0
on the grant's record
Examiner
Carman J. Seccuro
art unit —
Citations: 3 back · 0 forward

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