ratio of the units r 2 sio to rsio 1 5 is chosen from the range from 1 1 to 30 1 b siloxane elastomers which are insoluble and swellable in silicone oil and which are obtainable by the addition reaction of an organopolysiloxane 1 which contains silicon bonded hydrogen with an organopolysiloxane 2 which contains unsaturated aliphatic groups where the quantitative amounts used are chosen such that the amount of hydrogen in the organopolysiloxane 1 or in the unsaturated aliphatic groups of the organopolysiloxane 2 is in the range from 1 to 20 mol when the organopolysiloxane is noncyclic and is in the range from 1 to 50 mol when the organopolysiloxane is cyclic for the purposes of the present invention the siloxane elastomer or elastomers are advantageously present in the form of spherical powders or in the form of gels siloxane elastomers present in the form of spherical powders which are advantageous according to the invention are those with the inci name dimethiconeninyl dimethicone crosspolymer for example that available from dow corning under the trade names dow corning 9506 powder it is particularly preferred when the siloxane elastomer is used in combination with oils from hydrocarbons of animal or vegetable origin synthetic oils synthetic esters synthetic ethers or mixtures thereof it is very particularly preferred when the siloxane elastomer is used in combination with unbranched silicone oils which are liquid or pasty at room temperature or cyclic silicone oils or mixtures thereof organopolysiloxane elastomers with the inci name dimethicone polysilicone 11 very particularly the gransil grades obtainable from grant industries inc gcm gcm 5 dmg 6 cse gel pm gel ltx inin gel am 18 gel and dmcm 5 are particularly.