Color dyeing system for plastic films
US6652602B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 21, 2001 |
| Grant date | Nov 25, 2003 |
| Priority date | — |
| Expiry date | Feb 25, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S8/922
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A process for the continuous dyeing of plastic films, such as polyethylene terephthalate, is characterized by passing the film through a dye bath comprised of dye stuffs dissolved, suspended or dispersed in a liquid carrier comprised at least in part of a polymer, preferably a polyol, having at least one free hydroxyl group and a molecular weight within the range of from about 200 to about 600. The hydrogen bonding provided by the hydroxyl group, together with the high molecular weight and high boiling point of the polyol, mitigate against migration of the dye stuff out of the film, i.e., fading of the film, and impart long lasting color fastness to the film. Rapid diffusion of the dye bath into the film is enhanced by thermal and ultrasonic energization of the bath.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.