Patent · US Expired

Polypropylene films

US7098277B2 · kind B2 · utility

2Cited by
9References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 22, 2001
Grant dateAug 29, 2006
Priority date
Expiry dateOct 2, 2021

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08L2314/06
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

The present invention provides isotactic polypropylene compositions suitable for cast film applications, cast polypropylene films made therefrom, and processes for forming such films. The novel polypropylene films are formed from film resins having a melt flow ratio of from 6–15 dg/min, with a narrow molecular weight distribution, narrow composition distribution, low level of solvent extractables, and increased film clarity (i.e., decreased haze %) compared to prior art Ziegler-Natta polypropylene film resins. The polypropylene films can be cast from an extruded polypropylene polymer, the extruded isotactic polypropylene polymer being formed by polymerization with a fluorided silica supported catalyst.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.