Method for tinting a sheet of polyurethane
US4454170A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 12, 1982 |
| Grant date | Jun 12, 1984 |
| Priority date | — |
| Expiry date | Oct 12, 2002 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD06P3/26
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A method of tinting a sheet of transparent polyurethane comprising a coloring operation followed by a fixation operation. The aforesaid coloring operation is carried out through immersion of the polyurethane into a bath maintained under continuous agitation and formed of a dispersion of one or several colorants in an aqueous solution containing a surfactant or wetting agent, while the aforesaid fixation operation is carried out through rinsing in a boiling aqueous solution of sodium alkyl sulfonate of the type known under the mark "Teepol". The application to a double or composite sheet preformed to a thin laminate, that is to say, one layer of a thermoplastic polyurethane and one other layer of a thermosetting polyurethane. In a particularly useful embodiment of the invention the tinted polyurethane serves as a selective filter having almost zero transmission in the so-called cutoff range of wavelengths lying between about 350-560 nm. Eyeglasses made from such lenses are useful for victims of aphakia and retinitis pigmentosa.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.