Abstract:
The invention relates to the use of copolymers which comprise a) 60 to 99 % by weight of N-vinylcaprolactam; b) 1 to 40 % by weight of at least one monomer b) selected from the group including: b1) C8-C30 alkyl esters of monoethylenically unsaturated C3-C8 carboxylic acids; b2) N-alkyl- or N,N-dialkyl-substituted amides of the acrylic acid or the methacrylic acid with C8 to C30 alkyl groups; b3) the vinyl esters of aliphatically unbranched C8-C30 carboxylic acids; b4) the C8-C30 alkyl-vinyl ethers, as solubilizers for substances that are difficult to dissolve in water.