Process for preparing a treated paper coating pigment
US5322879A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 10, 1992 |
| Grant date | Jun 21, 1994 |
| Priority date | — |
| Expiry date | Dec 10, 2012 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01P2006/82
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
There is disclosed a paper coating composition comprising, in aqueous suspension, an adhesive and a treated paper coating pigment prepared by the following process: PA1 (i) suspending a paper coating pigment in water to form a suspension containing at least 5% by weight of the pigment, the pH being adjusted, if necessary, to lie below 7.5; PA1 (ii) mixing with the suspension formed in step (i) a water-soluble organic compound having a plurality of primary and/or secondary amine groups and a number average molecular weight not greater than 1000; and PA1 (iii) at least partially dewatering the mixed suspension resulting from step (ii) to form a dewatered suspension of a treated paper coating pigment containing not more than about 30% by weight water; characterized in that the water soluble organic compound is added in step (ii) in an amount sufficient to decrease the 5 poise viscosity concentration of an aqueous suspension of the treated pigment relative to that obtained with the untreated pigment. The paper coating composition is particularly suited to the preparation of a coated paper which is to be printed on by a gravure technique.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.