Rhombic-shaped scale device for use in judging discoloration, fading or staining
US4715716A · kind A · utility
Inventors
Key dates
| Filing date | Mar 28, 1986 |
| Grant date | Dec 29, 1987 |
| Priority date | — |
| Expiry date | Mar 28, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J3/52
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A scale device for use in judging the amount of discoloration or fading, or for judging the amount of staining, of a sample after a test of the sample for light fastness of dyeing or resistance to staining. The scale device has a plurality of scales of the same color having a plurality of patches with one portion of each patch having the same luminous reflectance and the other portions of the respective patches having successively varied luminous reflectances so as to give to the patches progressive values of color difference. The luminous reflectance of the one portions of the patches of each scale are different from the luminous reflectances of the one patches of the other scales. Four of the scales are arranged in a rhombic arrangement and the remainder of the scales are in a cross shape within the rhombic arrangement.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.