Patent ID: 6806341
Filing Date: 2004-10-19
Classification: C08F,C08G,C09J,Y10S

Abstract:
A method for forming an adhesive layer on a substrate which comprises:applying to the substrate a nonlonic, water-soluble polyurethane consisting essentially of the groups: (a) â€”Oâ€”(OH2â€”OH2 Oâ€”)n, wherein n is a number of 8-500; (b) â€”COâ€”NHâ€”Xâ€”NHâ€”COâ€” wherein X is an aliphatic or cycloeliphatic group; â€ƒand (c) â€”Oâ€”Yâ€”Oâ€”, wherein Y comprises a hydrophobic moiety selected from the group consisting of â€ƒ(â€”CH2â€”CH(CH3)â€”O)mâ€”CH2â€”CH(CH3)â€”, â€ƒ(CH2 CH(C2H5)â€”O)mâ€”CH2â€”CH(C2H5)â€”, â€ƒ(CH2â€”CH2â€”CH2â€”CH2 O)mâ€”CH2 CH2 CH2 CH2â€”, â€ƒalkylene groups having from 2 to 44 carbon atoms, cyoloalkylene groups having from 6 to 44 carbon atoms and mixtures thereof wherein m is a number of 8 to 500, the nonionic polyurethane forms a homogenous mixture with water; the mixture having a specific viscosity of at least 0.4 at a 1% by weight solution in water at 20Â° C. wherein (c) comprises from 2% to 40% by weight, based on (a)+(c) of the polyurethane and wherein at least one of the following conditions is met: (i) the nonionic polyurethane is soluble in water at any mixing ratio at 20Â° C.; (ii) n is 20 to 300 and m is 20 to 300 (iii) (c) comprises residues of a diol having a solubility in water not greater than 2 grams/100 grams of water; (iv) the equivalent ratio of (a) to (c) is greater than 1:1; (v) (c) comprises a hydrophobic polyoxyalkylene moiety wherein the alkylene group contains 3 or 4 atoms.