Microemulsion comprising, as component substantially forming the oil phase, A) polysiloxane containing at least one quaternary ammonium group and of the general formula M a M ' a1 M " a2 M '" a3 D b D ' b1 D " b2 D '" b3 T c T ' c1 Q d formula, where M = (R 1 3 Si O 1/2) M ' = (R 2 R 1 2 Si O 1/2) M " = (R 3 R 1 2 Si O 1/2) M '" = (R 4 R 1 2 Si O 1/2) D = (R 1 2 Si O 2/2) D ' = (R 2 R 1 Si O 2/2) D " = (R 3 R 1 Si O 2/2) D '" = (R 4 R 1 Si O 2/2) T = (R 5 Si O 3/2) T ' = (R 2 Si O 3/2) Q = (Si O 4/2) a = 0 to 32; preferably 0 to 22, in particular 0 to 12; a1 = 0 to 10, preferably 0 to 5, in particular 0; a2 = 0 to 32; preferably 0 to 22, in particular 1 to 12; a3 = 0 to 10; preferably 0 to 5, in particular 0; with the proviso that a + a1 + a2 + a3 ≥ 3, preferably > 3; b = 20 to 400; b1 = 0 to 10, preferably 0 to 5, in particular 0; b2 = 0 to 80, preferably 0 to 50, in particular 0 to 10; b3 = 0 to 20, preferably 0 to 10, in particular 0; c = 0 to 30, preferably 1 to 20, in particular 2 to 15; c1 = 0 to 10, preferably 0 to 5, in particular 0; d = 0 to 15, preferably 1 to 12, in particular 2 to 10; with the proviso that a2 + b2 ≥ 1, preferably ≥ 3, in particular > 3 and c + c1 + d ≥ 1, preferably > 1, in particular ≥ 3; R 1 methyl; R 2 = independently of one another identical or different alkoxy or acyloxy radicals, such as for example methoxy, ethoxy, n-propoxy or isopropoxy radicals, acetoxy, in particular ethoxy or isopropoxy radicals; R 3 = independently of one another identical or different organic radicals which carry quaternary ammonium functions; R 4 = independently of one another identical or different organic epoxy radicals; R 5 = independently of one another identical or different radicals R 1, R 3 or R 4, preferably R 1, in particular methyl, phenyl, dodecyl or hexadecyl. A) polysiloxane containing at least one quaternary ammonium group and of the general formula M a M ' a1 M " a2 M '" a3 D b D ' b1 D " b2 D '" b3 T c T ' c1 Q d formula, where M = (R 1 3 Si O 1/2) M ' = (R 2 R 1 2 Si O 1/2) M " = (R 3 R 1 2 Si O 1/2) M '" = (R 4 R 1 2 Si O 1/2) D = (R 1 2 Si O 2/2) D ' = (R 2 R 1 Si O 2/2) D " = (R 3 R 1 Si O 2/2) D '" = (R 4 R 1 Si O 2/2) T = (R 5 Si O 3/2) T ' = (R 2 Si O 3/2) Q = (Si O 4/2) a = 0 to 32; preferably 0 to 22, in particular 0 to 12; a1 = 0 to 10, preferably 0 to 5, in particular 0; a2 = 0 to 32; preferably 0 to 22, in particular 1 to 12; a3 = 0 to 10; preferably 0 to 5, in particular 0; with the proviso that a + a1 + a2 + a3 ≥ 3, preferably > 3; b = 20 to 400; b1 = 0 to 10, preferably 0 to 5, in particular 0; b2 = 0 to 80, preferably 0 to 50, in particular 0 to 10; b3 = 0 to 20, preferably 0 to 10, in particular 0; c = 0 to 30, preferably 1 to 20, in particular 2 to 15; c1 = 0 to 10, preferably 0 to 5, in particular 0; d = 0 to 15, preferably 1 to 12, in particular 2 to 10; with the proviso that a2 + b2 ≥ 1, preferably ≥ 3, in particular > 3 and c + c1 + d ≥ 1, preferably > 1, in particular ≥ 3; R 1 methyl; R 2 = independently of one another identical or different alkoxy or acyloxy radicals, such as for example methoxy, ethoxy, n-propoxy or isopropoxy radicals, acetoxy, in particular ethoxy or isopropoxy radicals; R 3 = independently of one another identical or different organic radicals which carry quaternary ammonium functions; R 4 = independently of one another identical or different organic epoxy radicals; R 5 = independently of one another identical or different radicals R 1, R 3 or R 4, preferably R 1, in particular methyl, phenyl, dodecyl or hexadecyl. M = (R 1 3 Si O 1/2) M ' = (R 2 R 1 2 Si O 1/2) M " = (R 3 R 1 2 Si O 1/2) M '" = (R 4 R 1 2 Si O 1/2) D = (R 1 2 Si O 2/2) D ' = (R 2 R 1 Si O 2/2) D " = (R 3 R 1 Si O 2/2) D '" = (R 4 R 1 Si O 2/2) T = (R 5 Si O 3/2) T ' = (R 2 Si O 3/2) Q = (Si O 4/2) a = 0 to 32; preferably 0 to 22, in particular 0 to 12; a1 = 0 to 10, preferably 0 to 5, in particular 0; a2 = 0 to 32; preferably 0 to 22, in particular 1 to 12; a3 = 0 to 10; preferably 0 to 5, in particular 0; with the proviso that a + a1 + a2 + a3 ≥ 3, preferably > 3; b = 20 to 400; b1 = 0 to 10, preferably 0 to 5, in particular 0; b2 = 0 to 80, preferably 0 to 50, in particular 0 to 10; b3 = 0 to 20, preferably 0 to 10, in particular 0; c = 0 to 30, preferably 1 to 20, in particular 2 to 15; c1 = 0 to 10, preferably 0 to 5, in particular 0; d = 0 to 15, preferably 1 to 12, in particular 2 to 10; with the proviso that a2 + b2 ≥ 1, preferably ≥ 3, in particular > 3 and c + c1 + d ≥ 1, preferably > 1, in particular ≥ 3; R 1 methyl; R 2 = independently of one another identical or different alkoxy or acyloxy radicals, such as for example methoxy, ethoxy, n-propoxy or isopropoxy radicals, acetoxy, in particular ethoxy or isopropoxy radicals; R 3 = independently of one another identical or different organic radicals which carry quaternary ammonium functions; R 4 = independently of one another identical or different organic epoxy radicals; R 5 = independently of one another identical or different radicals R 1, R 3 or R 4, preferably R 1, in particular methyl, phenyl, dodecyl or hexadecyl.