Patent ID: 8575244

Claim:
An aqueous polyurethane dispersion comprising a substituted N-(cyclo)alkylpyrrolidone (SCAP) of formula (1) wherein R 1 is an alkyl radical having 1 to 18 C atoms or a cycloalkyl radical having 3 to 18 C atoms, and R 2 , R 2 ′, R 3 , R 3 ′, R 4 and R 4 ′ are each independently selected from the group consisting of a hydrogen atom, an alkyl radical having 1 to 18 C atoms and a cycloalkyl radical having 3 to 18 C atoms, wherein at least one selected from the group consisting of R 2 , R 2 ′, R 3 , R 3 ′, R 4 and R 4 ′ is not a hydrogen atom.