Hardener for use in-urea-formaldehyde and urea-melamine-formaldehyde based adhesives, an adhesive composition comprising said hardener and its use

摘要

A hardener for use in urea-formaldehyde and urea-melamine-formaldehyde based adhesives comprises a polyvinyl acetate emulsion together with a metal chloride and an ammonium salt. The adhesive composition comprising a urea-formaldehyde or urea-melamine-formaldehyde resin, and the above hardener provides an increased curing rate, an acceptable viscosity, better adhesion and greater tolerance towards substrate type.