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

摘要

PCT No. PCT/DE93/01236 Sec. 371 Date Jun. 29, 1995 Sec. 102(e) Date Jun. 29, 1995 PCT Filed Dec. 20, 1993 PCT Pub. No. WO94/15982 PCT Pub. Date Jul. 21, 1994Urea-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.