A suspension of silica particles comprising: - a liquid [liquid] selected from the group consisting of the linear or branched, saturated or unsaturated, aliphatic and cycloaliphatic hydrocarbons having from 6 to 30 carbon atoms and of the aromatic hydrocarbons having from 6 to 10 carbon atoms, - silica particles, and - at least one compound [compound] selected from the group consisting of: i. the acid phosphate esters of formula P ((OCH 2 CH 2) n OR) a b wherein: R represents a linear or branched, saturated or unsaturated, aliphatic hydrocarbon group having from 1 to 24 carbon atoms or an aromatic hydrocarbon having from 6 to 24 carbon atoms; M is H, Na or K, n is an integer from 4 to 10, preferably from 4 to 8; a is an integer equal to 1 or 2, and b is 3-a; ii. the amines of formula NR 1 R 2 R 3 wherein R 1 =R 2 =H and R 3 =C 18 H 35; wherein R 1 =R 2 =-CH 2 CH 2 OH and R 3 =C 18 H 35 or; wherein R 1 =R 2 =- (CH 2 CH 2 O)n 1 H, the sum of n 1 in R 1 and R 2 is 5 and R 3 =C 18 H 35; iii. and the succinates of formula: R 4 OC CH 2 CHM 1 C OR 5 wherein R 4 and R 5 are independently selected from the group consisting of the linear or branched, saturated or unsaturated, aliphatic hydrocarbon groups having from 1 to 24 carbon atoms, preferably from 4 to 18 carbon atoms, and M 1 is either H or SO 3 Na; and iv. functionalised oligomers comprising recurring units deriving from at least one conjugated diene monomer, characterised in that said compound is miscible in liquid in the temperature range from 20°C to 50°C. - a liquid [liquid] selected from the group consisting of the linear or branched, saturated or unsaturated, aliphatic and cycloaliphatic hydrocarbons having from 6 to 30 carbon atoms and of the aromatic hydrocarbons having from 6 to 10 carbon atoms, - silica particles, and - at least one compound [compound] selected from the group consisting of: i. the acid phosphate esters of formula P ((OCH 2 CH 2) n OR) a b wherein: R represents a linear or branched, saturated or unsaturated, aliphatic hydrocarbon group having from 1 to 24 carbon atoms or an aromatic hydrocarbon having from 6 to 24 carbon atoms; M is H, Na or K, n is an integer from 4 to 10, preferably from 4 to 8; a is an integer equal to 1 or 2, and b is 3-a; ii. the amines of formula NR 1 R 2 R 3 wherein R 1 =R 2 =H and R 3 =C 18 H 35; wherein R 1 =R 2 =-CH 2 CH 2 OH and R 3 =C 18 H 35 or; wherein R 1 =R 2 =- (CH 2 CH 2 O)n 1 H, the sum of n 1 in R 1 and R 2 is 5 and R 3 =C 18 H 35; iii. and the succinates of formula: R 4 OC CH 2 CHM 1 C OR 5 wherein R 4 and R 5 are independently selected from the group consisting of the linear or branched, saturated or unsaturated, aliphatic hydrocarbon groups having from 1 to 24 carbon atoms, preferably from 4 to 18 carbon atoms, and M 1 is either H or SO 3 Na; and iv. functionalised oligomers comprising recurring units deriving from at least one conjugated diene monomer, i. the acid phosphate esters of formula P ((OCH 2 CH 2) n OR) a b wherein: R represents a linear or branched, saturated or unsaturated, aliphatic hydrocarbon group having from 1 to 24 carbon atoms or an aromatic hydrocarbon having from 6 to 24 carbon atoms; M is H, Na or K, n is an integer from 4 to 10, preferably from 4 to 8; a is an integer equal to 1 or 2, and b is 3-a; R represents a linear or branched, saturated or unsaturated, aliphatic hydrocarbon group having from 1 to 24 carbon atoms or an aromatic hydrocarbon having from 6 to 24 carbon atoms; M is H, Na or K, n is an integer from 4 to 10, preferably from 4 to 8; a is an integer equal to 1 or 2, and b is 3-a; ii. the amines of formula NR 1 R 2 R 3 wherein R 1 =R 2 =H and R 3 =C 18 H 35; wherein R 1 =R 2 =-CH 2 CH 2 OH and R 3 =C 18 H 35 or; wherein R 1 =R 2 =- (CH 2 CH 2 O)n 1 H, the sum of n 1 in R 1 and R 2 is 5 and R 3 =C 18 H 35; iii. and the succinates of formula: R 4 OC CH 2 CHM 1 C OR 5 wherein R 4 and R 5 are independently selected from the group consisting of the linear or branched, saturated or unsaturated, aliphatic hydrocarbon groups having from 1 to 24 carbon atoms, preferably from 4 to 18 carbon atoms, and M 1 is either H or SO 3 Na; and iv. functionalised oligomers comprising recurring units deriving from at least one conjugated diene monomer,