Method for treating the surface of particles, the thus obtained particles and use thereof

Particles comprising:

• TiO2, BaSO4, ZnS or lithopone with a coating comprising at least one compound of formula (I)
• in which
• R is methyl,
• R1 is a polyether group of formula (II):
• —Z—(O—CmH2m-(n-1))o—[O-(EOx,POy,BOz)—R3]n (II),
• in which
• Z is equal to an unbranched alkylene group having 2 to 4 carbon atoms,
• m is 2 to 4
• n is 1 to 3,
• o is 0,
• EOx, POy, BOz is an oxyalkylene group, containing oxyethylene (EO), oxypropylene (PO) and/or oxybutylene (BO) units, wherein x is 3 to 5, y is 10 to 25 and z is 0,
• R3 is hydrogen,
• and with the provision that in R1 the sum of carbon and oxygen atoms is at least 70,
• a is 80 to 95,
• b is 5 to 8, and
• comprising at least one phthalate-free plasticiser,
• wherein the at least one compound of formula (I) is present with a proportion of from 0.01 to 2% by weight, and at least one phthalate-free plasticiser is present with a proportion of from 0.01 to 4.0% by weight, wherein the values in % by weight relate to the weight of the used dried primary particles,
• wherein the at least one phthalate-free plasticiser comprises:
• esters of aliphatic hydrocarbons having 6 to 21 carbon atoms with at least one acid group selected from the group consisting of a carboxyl group, a sulfonyl group, and a sulfinyl group, with a monovalent or polyvalent aliphatic alcohol having 6 to 20 carbon atoms or a monovalent or bivalent aromatic alcohol, or
• esters of aromatic 1,4-(para)dicarboxylic acids or aromatic tricarboxylic acids with a monovalent or polyvalent aliphatic alcohol having 6 to 20 carbon atoms.