Color changing compositions for highlighters
US5492558A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 3, 1994 |
| Grant date | Feb 20, 1996 |
| Priority date | — |
| Expiry date | Oct 3, 2014 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB05D2451/00
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A multiple coloring composition system is disclosed wherein the coloring effect of a first undercolor coloring composition is changed upon treatment with a second coloring composition, once the second coloring composition has been deposited over the undercolor coloring composition. The multiple coloring composition system comprises: PA1 (a) an aqueous undercolor coloring composition comprising an undercolor dye whose coloring ability is destroyed in the presence of a pH of about 10 or greater and/or a reducing agent, and a compatible surfactant in an amount sufficient to increase the stability of said coloring composition; and PA1 (b) an aqueous overcolor coloring composition comprising an overcolor dye capable of maintaining its characteristic color in the presence of a pH of about 10 or greater and/or a reducing agent, an effective amount of a base sufficient to yield a pH of the aqueous overcolor coloring composition of about 10 or greater and/or a reducing agent, and a compatible surfactant in an amount sufficient to increase the capillary flow of said aqueous overcolor coloring composition. The multiple coloring composition system is especially useful for highlighting text ina…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.