Method for obtaining composite materials based on polymers and liquid crystals with dichroic dyes
US5430563A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 23, 1994 |
| Grant date | Jul 4, 1995 |
| Priority date | — |
| Expiry date | Feb 23, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/1334
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Disclosed is an original method for preparing composite materials for a display screen, these materials containing a polymer, liquid crystal and dye. The present problem is one of inserting molecules of dye into composites of this type. The disclosed method proposes the preparation, in a first step, of a porous film of reticulate polymer. Then, molecules of liquid crystal (XL) and molecules of dye (C) are made to diffuse therein by a polymer-expanding solvent. After evaporation of the solvent, a film of polymer is obtained with inclusions containing liquid crystal (XL) and dye (C) with a wide range of concentrations in liquid crystal, thus making it possible to optimize the performance characteristics in terms of contrast and control voltage of the screen thus made.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.