Verfahren zur Herstellung von Phenol-Formaldehyd-Kondensationsprodukten und Verwendung der Phenol-Formaldehyd-Kondensationsprodukte als Druckfarben-Bindemittel

摘要

1,230,240. Phenolic resins. SOC. ITALIANA RESINE S.p.A. 30 Dec., 1969 [31 Dec., 1968], No. 63367/69. Heading C3R. A phenolic resin is prepared by condensing pcumyl phenol, formaldehyde and rosin at 130-270‹ C. in the presence of a salt of Ca, Mg, Mn or Zn with an acid having a dissociation constant of less than 1À8 Î 10-5, the molar ratio of aldehyde to phenol being between 2.5 and 4 to 1 and the weight of rosin being 1À5 to 2 times that of phenol. The formaldehyde may be paraformaldehyde, and the salt may be ZnCO 3 . A polyol, e.g. glycerol, sorbitol or pentaerythritol may also be present.