The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 25, 2003
Filed:
Dec. 21, 2001
Xiaoming Yang, San Diego, CA (US);
Raymond B. Turner, San Diego, CA (US);
N.V. Bekaert S.A., Zwevegem, BE;
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.