IMPROVED COATINGS WITH LOW TITANIUM DIOXIDE CONTENT Russian patent published in 2015 - IPC C09D7/00 C09D7/12 C09D5/02 C09D133/00 

FIELD: chemistry.

SUBSTANCE: invention relates to reduced energy content pigmented coating compositions, especially paints with low medium sheen, as well as to articles or structures having a surface coated with said composition. An aqueous coating composition having 78-85% PVC, comprising, based on the total volume solid substances of the dry coating unless otherwise stated: a) dulling pigment particles comprising: i) 3 to 10% titanium dioxide, ii) 0 to 20% of hollow polymer particles, having voids of 30 to 50% of the volume of the particles; b) non-dulling filler particles comprising: i) magnesium calcium carbonate, and/or ii) calcium carbonate, and/or iii) nepheline syenite, and/or iv) kaolin, wherein i)+ii)+iii)+iv)=40-80% and iv) is 0- 20%. The composition also comprises c) polymer binder particles of calculated Fox Tg of 25 to 70°C having an acid number of 15 to 65 mg KOH/g of polymer and wherein the polymer particles of the binder are latex polymer particles. Said polymer particles are derived from acrylic monomers and optionally further comprise styrene and/or derivatives thereof. The composition also comprises d) a dispersant having average molecular weight of at least 3500 Da and selected based on that the need, in the dispersant, for a mixture of dulling pigment particles differs from hollow polymer particles in (a) and filler particles in (b) and is greater than 0.35 wt % with respect to the weight of titanium dioxide and the filler particles. The composition comprises e) a volatile coalescent solvent. The present aqueous composition is free of a non-volatile coalescent solvent.

EFFECT: obtaining a reduced energy content pigmented coating composition.

20 cl, 2 dwg, 1 tbl, 7 ex