Thermographic cholesteric coating compositions and plates
US4441508A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 16, 1981 |
| Grant date | Apr 10, 1984 |
| Priority date | — |
| Expiry date | Nov 16, 2001 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/249997
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Thermographic plates particularly for medical investigation are provided comprising a polymer film substrate coated with single-droplet microcapsules having core material consisting essentially of about 55 to about 75% of cholesteryl pelargonate, about 14 to about 35% isostearyl cholesteryl carbonate, about 2.0 to about 6.0% of cholesteryl propionate and about 4.5 to about 7.2% of cholesteryl chloride. The coated plates give a gray-red-green-blue temperature-responsive visual display over a 3.degree. or 4.degree. C. range. Thermographic plates wherein the coatings contain two different microencapsulated formulations, both selected from the above formulation range, show a temperature responsive visual display of seven distinct color shades over about a 4.degree.-7.degree. C. range.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.