Method of dyeing a plastic article
US7175675B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 11, 2003 |
| Grant date | Feb 13, 2007 |
| Priority date | — |
| Expiry date | Mar 13, 2024 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD06P5/00
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
In the method of the present invention a plastic article (e.g., a molded article of thermoplastic polycarbonate) is immersed at least partially in a dye bath which includes one or more dyes, water, at least one carrier, and at least one diol. The dye bath contains: (i) at least one dye (e.g., a static and/or photochromic dye); (ii) water; (iii) at least one carrier represented by the following general formula I,R—O—(CH2)n—OHIwherein R is a radical selected from linear or branched C1–C18 alkyl, benzyl, benzoyl and phenyl, and n is 2 or 3; and (iv) a diol selected from at least one of linear or branched C2–C20 aliphatic diols, poly(C2–C4 alkylene glycol), cycloaliphatic diols having from 5 to 8 carbon atoms in the cyclic ring, monocyclic aromatic diols, bisphenols and hydrogenated bisphenols. In an embodiment of the present invention, the carrier is ethyleneglycol butyl ether, and the diol is diethylene glycol. The present invention also relates to a method of separating the dye from the water, carrier and diol components of the dye bath, by contacting the dye bath with particulate activated carbon.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.