Patent · US Expired

Composite films free from metal layers

US5145731A · kind A · utility

38Cited by

5References

7Claims

0Family size

Assignee

Wolff Walsrode AG · DE

Inventors

Klaus Lund · Walsrode, DE
Holger Preiss · Visselhövede, DE

Key dates

Filing date	Mar 19, 1990
Grant date	Sep 8, 1992
Priority date	—
Expiry date	Mar 19, 2010

Classification

Technology area (CPC Y)Emerging Cross-Sectional Technologies
CPC primaryY10T428/3192
WIPO fieldSurface technology, coating
WIPO sectorChemistry

Abstract

The composite film contains individual layers of polyvinyl alcohol, a polyolefin, an ethylene/vinyl alcohol and a polyolefin in that order and is comparable in its barrier properties to water vapor and gas with composite films containing metal layers without having any of their disadvantages.

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