| 摘要 |
PURPOSE:To obtain consistentlyh the titled resin having no corrosiveness and excellent storage stability, by condensing a phenol with an aldehyde in the presence of a catalyst and dehydrating and solidifying the reaction solution by rapid colling when its viscosity reaches a specified value, pulverizing the product into small particles and drying the product. CONSTITUTION:An aqueous solution of a total concentration of 60-90wt% containing 1mol of a phenol (e.g., phenol) and 1.1-1.9mol of an aldehyde (e.g., formualin) is heated to 50-90 deg.C in the presence of 0.054-0.2mol of a nonammoniac alkaline catalyst such as an alkaki (alkaline earth) metal or zinc (hydr)oxide and, optionally, 20wt% or below, based onthe phenol, urea, melamine, aniline or the like to effect the (co)condensation of the monomers, and when the viscosity of the reaction solution reaches 5-30p (at 40 deg.C), the reaction solution is dehydrated and vacuum-concentrated by heating at dimin ished pressure of 5-50Torr to a water content of 1-2wt% and immediately solifdified by cooling crushed by a primary crusher or the like into small particles of a particle diameter of about 5-20mm to obtain the title composition excellent in stability of quality, blocking resistance, moldability and curability.
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