Patent ID: 6630050
Filing Date: 2003-10-07
Classification: B65C,C08G

Abstract:
An adhesive composition comprising: a polyurethane comprising a reaction product ofa) at least one diisocyanate; and b) at least one low molecular weight polyethylene glycol, wherein, said polyethylene glycol has a molecular weight Mz up to 2,000, and; wherein, said polyurethane has a degree of crystallization of less tan 20 percent, as measured by a DSC method, based on a degree of crystallization of polyethylene glycol 6000 as a standard, is permanently tacky and is water-soluble or dispersible in water, wherein, said low molecular weight polyethylene glycol is partly replaced by at least one polyol selected from the group consisting of: a) up to 50 percent by weight of a block or statistical copolymer of ethylene oxide; b) up to 20 percent by weight of a hydrophobic aliphatic or cycloaliphatic diol; c) up to 10 percent by weight of hydrophobic homopolymeric polyalkylene glycols, wherein the alkylene group in said glycols contains more than 2 carbon atoms and said glycols have a molecular weight of from 150 to 10,000; d) up to 40 percent by weight of polyethylene glycol with a molecular weight of from 2,000 to 40,000; e) up to 5 percent by weight of triols; and f) up to 5 percent by weight of ion-forming diols, said percentages shown representing percent by weight, based on the total weight of said polyethylene glycol and polyols and; wherein, the diisocyanate can contain up to 50% by weight of TMXDI based on the weight of the diisocyanate.