Process for producing urea-modified, highly reactive phenolic resins useful as bonding agents for center-layer particles in the manufacture of particleboard

摘要

Urea-modified, highly reactive phenolic resins useful as center-layer bonding agents in the manufacture of particleboard are provided by condensing phenol and formaldehyde until shortly before gelation takes place such that, after addition of urea, relatively low- alkaline, urea- modified phenolic resins are obtained which my optionally be stored and to which, shortly before processing them into glues for center-layer particles, alkali is added in sufficient quantities to ensure rapid cross- linking of the phenolic resin.