Compatibilizing agent, polyester polyol mixture containing the same, and hot-melt adhesive obtained from the mixture

A polyester polyol mixture which comprises

• (1) from 10 to 90 parts by weight of a polyester polyol comprising units derived from
• at least one aliphatic dicarboxylic acid (A) having n carbon atoms wherein n is from 10 to 20 and
• at least one aliphatic diol having k carbon atoms wherein k is from 2 to 12,
• (2) from 90 to 10 parts by weight of a polyester polyol comprising units derived from
• at least one aliphatic dicarboxylic acid (B) having m carbon atoms wherein m is from 2 to 9 and
• at least one aliphatic diol having k carbon atoms wherein k is from 2 to 12,
• (3) from 5 to 100 parts by weight of a compatibilizing agent comprising a polyester polyol which comprises units derived from:
• at least one aliphatic dicarboxylic acid (A) having n carbon atoms wherein n is from 10 to 20,
• at least one aliphatic dicarboxylic acid (B) having m carbon atoms wherein m is from 2 to 9, and
• at least one aliphatic diol having k carbon atoms wherein k is from 2 to 12;
• in which n-m ≧4 and the molar ratio of ingredient (A) to ingredient (B) in the compatibilizing agent is from 90:10 to 10:90 and
• (4) from 0 to 50 parts by weight of a polyalkylene glycol,
• provided that the sum of ingredients (1) and (2) is 100 parts by weight and n-m ≧4.