Patent · US Expired

Pigments and their manufacture

US4563221A · kind A · utility

11Cited by
5References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 15, 1985
Grant dateJan 7, 1986
Priority date
Expiry dateMar 15, 2005

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC01P2004/84
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

Pigments for use in plastics should produce a composition containing as few nibs or aggregates as is possible and also develop as little dust as possible during handling. A new pigment has now been developed which comprises particulate titanium dioxide having an organic coating of isostearic acid, dodecyl benzene sulphonic acid and a cationic emulsifying agent of a fatty alkyl amine. The pigment particles should be free of an inorganic coating. A method of manufacture of the pigment is disclosed in which the isostearic acid and dodecyl benzene sulphonic acid are emulsified in water prior to addition of an aqueous dispersion of the pigment. Remarkably it has been discovered that after treatment the pigment does not require milling in a fluid energy mill and that separation from the supernatant liquid can be effected by decantation.

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