An organopolysiloxane, containing at least 50 mol% of trifunctional siloxane units and at least one trifunctional siloxane unit having a polyether group, selected from (i) polysiloxane containing units of formula R 1 a (R 2 O) b R 3 c SiO (4-a-b-c)/2 where R 1 is independently at each occurrence a monovalent, optionally substituted, SiC-bonded hydrocarbon radical, R 2 is independently at each occurrence hydrogen or a monovalent, optionally substituted hydrocarbon radical, R 3 is independently at each occurrence a radical of formula -O-R a -(OR b) j -O-R c wherein R a is a divalent, optionally substituted hydrocarbon radical, R b is independently at each occurrence a divalent, optionally substituted hydrocarbon radical, R c is hydrogen, a monovalent organic radical or has a structure fragment of wherein R* is independently at each occurrence R 1, OR 2 or -O-, j is an integer of from 1 to 200, a is 0, 1, 2 or 3, b is 0, 1, 2 or 3, and c is 0, 1 or 2, with the proviso that in at least 50 mol% of all of the units of formula a is 1 and the sum b+c is 0, 1 or 2, of which in at least 1 unit c is different from 0; or (ii) polysiloxane containing units of formula R 1' d R 3' e SiO (4-d-e)/2 where R 1' is independently at each occurrence a monovalent, optionally substituted, SiC-bonded hydrocarbon radical, R 3' is independently at each occurrence a radical of formula -R a ' -(OR b ') j' -O-R c ' wherein R a ' is a divalent, optionally substituted hydrocarbon radical, R b ' is independently at each occurrence a divalent, optionally substituted hydrocarbon radical, R c ' is hydrogen, a monovalent organic radical or has a structure fragment of wherein R*' is independently at each occurrence R 1' or -O- and r is an integer of from 1 to 6, j ' is an integer of from 1 to 200, d is 0 or 1, and e is 0 or 1, with the proviso that in at least 50 mol% of all of the units of formula the sum d+e is 1, of which in at least 1 unit e is different from 0. (i) polysiloxane containing units of formula R 1 a (R 2 O) b R 3 c SiO (4-a-b-c)/2 where R 1 is independently at each occurrence a monovalent, optionally substituted, SiC-bonded hydrocarbon radical, R 2 is independently at each occurrence hydrogen or a monovalent, optionally substituted hydrocarbon radical, R 3 is independently at each occurrence a radical of formula -O-R a -(OR b) j -O-R c wherein R a is a divalent, optionally substituted hydrocarbon radical, R b is independently at each occurrence a divalent, optionally substituted hydrocarbon radical, R c is hydrogen, a monovalent organic radical or has a structure fragment of wherein R* is independently at each occurrence R 1, OR 2 or -O-, j is an integer of from 1 to 200, a is 0, 1, 2 or 3, b is 0, 1, 2 or 3, and c is 0, 1 or 2, with the proviso that in at least 50 mol% of all of the units of formula a is 1 and the sum b+c is 0, 1 or 2, of which in at least 1 unit c is different from 0; or where R 1 is independently at each occurrence a monovalent, optionally substituted, SiC-bonded hydrocarbon radical, R 2 is independently at each occurrence hydrogen or a monovalent, optionally substituted hydrocarbon radical, R 3 is independently at each occurrence a radical of formula -O-R a -(OR b) j -O-R c wherein R a is a divalent, optionally substituted hydrocarbon radical, R b is independently at each occurrence a divalent, optionally substituted hydrocarbon radical, R c is hydrogen, a monovalent organic radical or has a structure fragment of wherein R* is independently at each occurrence R 1, OR 2 or -O-, j is an integer of from 1 to 200, a is 0, 1, 2 or 3, b is 0, 1, 2 or 3, and c is 0, 1 or 2, with the proviso that in at least 50 mol% of all of the units of formula a is 1 and the sum b+c is 0, 1 or 2, of which in at least 1 unit c is different from 0; or (ii) polysiloxane containing units of formula R 1' d R 3' e SiO (4-d-e)/2 where R 1' is independently at each occurrence a monovalent, optionally substituted, SiC-bonded hydrocarbon radical, R 3' is independently at each occurrence a radical of formula -R a ' -(OR b ') j' -O-R c ' wherein R a ' is a divalent, optionally substituted hydrocarbon radical, R b ' is independently at each occurrence a divalent, optionally substituted hydrocarbon radical, R c ' is hydrogen, a monovalent organic radical or has a structure fragment of wherein R*' is independently at each occurrence R 1' or -O- and r is an integer of from 1 to 6, j ' is an integer of from 1 to 200, d is 0 or 1, and e is 0 or 1, with the proviso that in at least 50 mol% of all of the units of formula the sum d+e is 1, of which in at least 1 unit e is different from 0. where R 1' is independently at each occurrence a monovalent, optionally substituted, SiC-bonded hydrocarbon radical, R 3' is independently at each occurrence a radical of formula -R a ' -(OR b ') j' -O-R c ' wherein R a ' is a divalent, optionally substituted hydrocarbon radical, R b ' is independently at each occurrence a divalent, optionally substituted hydrocarbon radical, R c ' is hydrogen, a monovalent organic radical or has a structure fragment of wherein R*' is independently at each occurrence R 1' or -O- and r is an integer of from 1 to 6, j ' is an integer of from 1 to 200, d is 0 or 1, and e is 0 or 1, with the proviso that in at least 50 mol% of all of the units of formula the sum d+e is 1, of which in at least 1 unit e is different from 0.