Patent ID: 6906148

Claim:
A polyurethane hot melt adhesive composition comprising: (a) at least one reaction product of at least one polyisocyanate with at least one polyester block copolymer of the formula: HO—R 2 —O-A-O—R 1 —OH (I) (b) optionally at least one reaction product selected from the group consisting of reaction of polyisocyanates with polyester polyols, reaction products of polyisocyanates with polyether polyols and mixtures thereof; wherein A represents —R 3 —X —C(O) —R 4 —C(O)—X —R 5 —R 1 and R 2 independently represent (—(CH 2 ) 4 —O—(CH 2 ) 4 —) o , (—C 3 H 6 —O—C 3 H 8 —) o , (—C 2 H 4 —O—C 2 H 4 —) p , a polycarborlate residue, a polycaprolactone residue or a combination thereof, X+R 3 together represent a covalent bond or X represents O and R 3 represents —(CH 2 ) m —, and R 4 represents a residue of a polyester, having carboxyl end groups, of at least one C 4 -C 12 diol and at least one C 6 -C 14 dicarboxylic acid after removal at the terminal carboxyl groups, and m=4 to 12, o=5-80 and p=5-80.