Conditioning of organic pigments

US6890380B2 · kind B2 · utility

Assignee

• Ciba Specialty Chemicals Corporation · US

Inventors

• Gerhard Giger · Muttenz, CH
• Jürgen Beyrich · Huttingen, DE
• Philippe Bugnon · Le Mouret, CH
• Marc Maurer · Compiègne, FR

Key dates

• Filing date: Jan 31, 2002
• Grant date: May 10, 2005
• Expiry date: Jan 31, 2022

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C09B67/0022
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

Organic pigments are conditioned by treating them, after synthesis but preferably without or with only partial drying, in a mixture of from 1 to 30% by weight of a neutral, polar liquid having a dipole moment μ of 2.8-6.0? 10−18 esu (2.8 to 6.0 debye units) and from 70 to 99% by weight of water in an agitated media pearl mill having a specific power density of at most 2.0 kJs?−1 per liter of grinding space. Drying is especially suitable in the case of only slightly agglomerating, easy to wet pigments of specific surface area from 1 to 25 m2/g. The method gives excellent results, and is flexible and also much simpler than known methods.