Process for making coated polypropylene film
US5302327A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 17, 1993 |
| Grant date | Apr 12, 1994 |
| Priority date | — |
| Expiry date | May 17, 2013 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08J2323/10
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A process for producing thermoplastic film which is an antifogging, heat-sealable polypropylene film; the antifogging agent is a polyglycerol ester or a sorbitan ester of a fatty acid. The resultant film, which has good clarity, persistent antifogging characteristics, and excellent heat sealability, is useful for packaging refrigerated foods. The disclosure also provides a process for making the film in which the polypropylene-containing thermoplastic resin is extruded into a sheet with subsequent orientation of said sheet in the longitudinal direction to form a monoaxially oriented film; the film is then oriented in the transverse direction.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.