Composite pigments and process for their preparation
US4486237A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 22, 1983 |
| Grant date | Dec 4, 1984 |
| Priority date | — |
| Expiry date | Feb 22, 2003 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01P2006/60
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Novel composite pigments containing both organic and inorganic portions have been produced. These pigments consist of an inorganic binary titanium dioxide/aluminum hydrate component, in a percent quantity comprised between 70% and 95% by weight, the remaining organic component amounting to between 5% and 30% by weight, consisting of an organic dye selected from the group consisting of azoic and quinophtalonic compounds, containing in their structure at least one carboxylic and/or sulphonic, substantially salified, acid function. The pigments are obtained according to a co-precipitation process, under substantially alkaline controlled pH conditions, of the acid organic dye together with the aluminum hydroxide (hydrated aluminum), by acidification of a solution and/or an aqueous dispersion of the acid organic dye in sodium aluminate, in the presence of titanium dioxide, at from 40.degree. C. to about 80.degree. C., and by a subsequent lacquering by treatment with an aqueous solution of an alkaline-earth metal salt (Ca, Mg, Ba, Sr) or of a Mn, Zn salt. The above-mentioned pigments are insoluble in water and in common organic solvents. They possess, moreover, a good dyeing power, an ex…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.