ALKID FOR PIGMENT PASTE Russian patent published in 2021 - IPC C08G63/48 C08G63/52 C08G63/91 C08K3/13 C08K3/11 C08K3/22 C09D7/61 C09D17/00 C09D167/07 C09D167/08 

FIELD: chemistry.

SUBSTANCE: invention can be used in the paint and varnish industry. The organic solvent-based pigment paste contains at least 10 wt% of alkyd and at least 1 wt% of one or more iron oxide pigments. To prepare an alkyd, an OH-functional alkyd is first prepared from a non-drying oil or fatty acid, one or more polyols and an anhydride. The non-drying oil or fatty acid has an iodine number of ≤115, which is determined according to ISO 3961. The OH-functional alkyd is then esterified with trimellitic anhydride (TMA) at a temperature of 220°C to obtain an alkyd with esterified TMA residues, where at least 80% of the esterified TMA residues have two free carboxyl groups. The acid number of the resulting alkyd is from 15 to 30 mg KOH/g, which is determined according to ISO 2114. The proposed coating contains the specified pigment paste.

EFFECT: invention makes it possible to obtain a pigment paste that remains stable and does not gel over time.

18 cl, 2 dwg, 4 tbl