Patent ID: 8906460

Claim:
A composition capable of forming a translucent coating on a construction material surface, comprising: a) photocatalytic titanium dioxide particles having a de-NO x activity, the photocatalytic titanium dioxide particles consisting essentially of at least 50% by mass of an anatase crystalline form having a mean size range of from 1 nm up to 150 nm and a surface area per gram of at least 30 m 2 /g, b) a silicon based-material in which said photocatalytic titanium dioxide particles are dispersed, wherein said silicon based material includes at least one polysiloxane derivative having the formula wherein R 1 and R 2 are alkyl radicals of from 1 to 20 carbon atoms or phenyl, and c) de-HNO 3 particles having a de-HNO 3 activity, wherein the de-HNO 3 particles are selected from the group consisting of calcium carbonate, magnesium carbonate and mixtures thereof, wherein (i) the photocatalytic titanium dioxide particles and the de-HNO 3 particles are present in an amount lower than 20% by weight of the total weight of said composition, and the photocatalytic titanium dioxide particles are present in an amount of at least 5% by weight of the total weight of said composition, (ii) the ratio of de-HNO 3 particles to photocatalytic titanium dioxide particles is in the range of from 0.05 to 2.