A method for increasing an adhesive to a substrate is disclosed which utilizes a hydrophilic, high molecular weight, nonionic polyurethane adhesive. The polyurethane adhesive is soluble in water and a 1% by weight solution of the adhesive in water at 20% has a specific viscosity of at least 0.4. The nonionic polyurethane contains the following structural units:

• a) —O—(CH₂—CH₂O)_n where n is 8 to 500;
• b) —CO—NH—X—NHCO— where X is an aliphatic or cycloaliphatic group; and
• c) —O—Y—O— wherein Y comprises a hydrophobic moiety from the groups
  • (—CH₂—CH(CH₃)—O)_m—CH₂—CH(CH₃)—,
  • (—CH₂ CH(C₂H₅)—O)_m—CH₂—CH(C₂H₅)—,
  • (—CH₂—CH₂—CH₂—CH₂O)_m—CH₂CH₂CH₂CH₂—,

    alkylene groups having from 2 to 44 carbon atoms, cycloalkylene groups having from 6 to 44 carbon atoms and mixtures thereof.