Abstract: Large-scale preparation of branched novolacs by the acid catalyzed, exothermic condensation of methylol-reactive phenols with polymethylol diphenols is made practical by first carrying out the reaction on a scale which permits temperature control simply by cooling and then separately adding more of the premixed reactants and the catalyst at rates such that the temperature of the reaction mixture can readily be controlled.

Abstract: Thermosetting resin coatings are provided which cure rapidly and exothermically at ambient temperatures. Accelerated crosslinking is accomplished by the reaction of oxalic acid esters with amine-containing polymeric compositions.

Abstract: A color developer for pressure-sensitive copying papers is prepared by mixing a para-substituted difunctional phenol-aldehyde condensate and tri- or higher-functional phenol-aldehyde condensate. The tri- or higher-functional phenol-aldehyde condensate can be modified by a polyvalent metal.

Abstract: A color developer for pressure-sensitive copying paper is prepared by mixing a polyvalent metal salt of a para-substituted difunctional phenol-aldehyde condensate and a tri- or higher-functional phenol-aldehyde condensate and/or a polyvalent metal modified tri- or higher-functional phenol-aldehyde condensate.

Abstract: Mineral tanned leather is frequently retanned with synthetic tanning agents to improve the fullness and softness, but leather retanned by the prior art methods is difficult to dye in full shades with anionic dyes. According to the invention, condensation products of C.sub.1-4 aldehydes with certain aromatic sulfonic acids or carboxylic acids containing amino groups are employed for retanning, thereby improving the receptivity of the leather for anionic dyes. These acids have the general formula ##STR1## where X and X' are independently H, --CH.sub.2 --SO.sub.3 H or --CH.sub.2 --OH, A is a benzene radical, Y and Z are independently H, --SO.sub.3 H or --CO.sub.2 H, R is H or C.sub.1-4 -alkyl and n is from 0 to 10, with the proviso that at least one sulfonic acid or carboxyl group is present in the molecule.

Abstract: A resin prepared by acid-catalytic condensation of p-phenylphenol with formaldehyde in the presence of an alcohol having a boiling point of 70.degree. C. or more is improved in solubility in various solvents, especially in ethyl acetate, polyethylene glycol and oil, and is useful as an acidic substance in No Carbon copying paper, which gives an intense color with higher speed, especially in the form of spot ink in flexographic printing or gravure printing.

Abstract: A high-molecular-weight novolak type substituted phenolic resin having a number average molecular weight of at least 1500 is prepared by reacting (A) (i) a phenol comprised mainly of a bifunctional phenol or (ii) a low-molecular-weight novolak type substituted phenolic resin derived from this phenol and an aldehyde with (B) a chain extender selected from the group consisting of (i) a dimethylolated product of a bifunctional or trifunctional phenol, (ii) a low-molecular-weight resol type substituted phenolic resin derived from a phenol comprised mainly of a bifunctional phenol and an aldehyde, (iii) an aldehyde, (iv) a ketone, (v) a diol and (vi) a dihalide in the presence of an acid catalyst, with the proviso that if the reactant (A) is the phenol (i), the chain extender is the resol type substituted phenolic resin (ii).

Abstract: A water-base well drilling, workover or completion fluid containing a fluid loss control agent prepared by pre-reacting sulfonated phenol with formaldehyde under alkaline conditions and then reacting the mixture with phenol under controlled conditions is described.

Abstract: A color developer for pressure-sensitive copying paper is prepared by mixing a polyvalent metal salt of a para-substituted difunctional phenol-aldehyde condensate and a tri- or higher-functional phenol-aldehyde condensate and/or a polyvalent metal modified tri- or higher-functional phenol-aldehyde condensate.

Abstract: A color developer for pressure-sensitive copying papers is prepared by mixing a para-substituted difunctional phenol-aldehyde condensate and tri- or higher-functional phenol-aldehyde condensate. The tri- or higher-functional phenol-aldehyde condensate can be modified by a polyvalent metal.