Patent · US Expired

Modified form of disazo pigment CI 20040

US4048152A · kind A · utility

2Cited by

4References

1Claims

0Family size

Assignee

Hoechst GmbH · DE

Inventors

Joachim Ribka · Offenbach am Main, DE
Wolfgang Rieper · Frankfurt am Main, DE
Siegfried Schwerin · Hofheim, DE

Key dates

Filing date	Nov 11, 1975
Grant date	Sep 13, 1977
Priority date	—
Expiry date	Nov 11, 1995

Classification

Technology area (CPC C)Chemistry; Metallurgy
CPC primaryC09B67/0015
WIPO fieldBasic materials chemistry
WIPO sectorChemistry

Abstract

A form of the disazo pigment C.I. 20040 having the formula 30% of ##STR1## IS SHOWN HAVING IMPROVED COVERING POWER, IMPROVED FLUIDITY IN LACQUER SYSTEMS AND HIGH LUSTER, WHICH IS CHARACTERIZED BY A SPECIFIC SURFACE OF 10 - 20, PREFERABLY 12 - 17 M.sup.2 /G AND A MAXIMUM IN GRAIN DIAMETER DISTRIBUTION BETWEEN 500 AND 1000 NM, AT LEAST 30 % OF ALL GRAINS HAVING A DIAMETER OF FROM 500 TO 1000 NM AND LESS THAN 25% OF ALL GRAINS HAVING A DIAMETER OR MORE THAN 1000 NM. This new pigment is obtained by isolating the pigment, after coupling, by stirring it out with alkali and, after having filtered it off and washed until neutrality, heating it to temperatures above 100.degree. C with an organic solvent which is immiscible with water or miscible with water to a limited degree only.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.