Antifoam formulations

An antifoam formulation comprising:

• (A) at least one siloxane antifoam based on siloxane composition, and
• (B) at least one branched polyether/polysiloxane copolymer comprising structural elements of the formula
• Y[—CnH2n—(R2SiO)m—Ap—R2Si—G]x (I)
• in which
• Y is a trivalent to decavalent, hydrocarbon radical optionally containing one or more hetero atoms selected from the group consisting of the oxygen, nitrogen and silicon,
• R are identical or different monovalent, optionally halogenated hydrocarbon radicals having 1 to 18 carbon atoms per radical,
• A is a radical of the formula
• —R2Si—R2—(R2SiO)m—, in which R2 is a divalent hydrocarbon radical which has 2 to 30 carbon atoms and may be interrupted by one or more non-adjacent oxygen atoms,
• G is a monovalent radical of the formula —CfH2f-2k—Z, or a divalent radical of the formula —CnH2n— in which the second bond is to a further radical Y,
• Z is a radical of the formula
• —(R6)v—(OCH2CH2)a[OCH2CH(CH3)]b[OCH2CH(CH2CH3)]c—OR3,
• in which R3 is a hydrogen atom, a hydrocarbon radical having 1 to 18 carbon atoms, or a radical of the formula R—C(O)—,
• R6 is a divalent hydrocarbon radical having 1 to 10 carbon atoms,
• v is 0 or 1,
• a, b and c are 0 or an integer between 1 and 1000,
• with the proviso that the sum (a+b+c) has a value of from 2 to 2000,
• x is an integer from 3 to 10,
• f is an integer from 2 to 12,
• k is 0 or 1,
• n is an integer from 2 to 12,
• m is an integer of at least 1, and
• p is 0 or a positive integer,
• with the proviso that the branched polyether/polysiloxane copolymers (B) contain on average at least one group Z.