Societa' Italiana Resine S.i.r. S.p.a.

Euteco, S.p.a.

Mario Bernasconi

Silvio Vargiu

Pier L Manzoni

Antonio Parodi

Novolak phenolic resin compositions are formed into molding granules by homogenizing the composition above the melting point of the resin, calendering the homogenized composition with conversion into a coherent sheet, rolling the sheet between a pair of rollers, at least one of which is indented, to produce a coherent embossed sheet, fracturating the embossed sheet with separation of the granules having substantially the shape and size of the embossments, coating the granules with a phenolic compound and heat-treating the coated granules by flowing a stream of inert gas having a temperature not exceeding 130.degree. C. The resulting granules are free-flowing, free from a tendency to release dust and particularly suitable for injection molding.

Process for forming novolak resin compositions into molding granules

A granular thermosetting composition free from a tendency to release dust and transformable into molded articles free from surface defects, is obtained by forming the composition into granules of from 2 to 8 mm in size and mixing said granules with from 0.5 to 3 wt.% of one or more substances, in liquid form, chosen from acetone, phenol, aniline and reaction products of phenol with styrene.

Method for preparing a granular thermosetting moulding composition

A thermosetting molding composition comprising from 15 to 50 wt.% of Novolak phenolic resin; from 3 to 10 wt.% of hexamine; from 1 to 4 wt.% of a stabilizing-catalyzing mixture consisting of an amine chosen from polyamino aliphatic compounds and mono or polyamino aromatic compounds, and orthoboric or metaboric acid, wherein the ratio between said amino groups and the number of acid equivalents in said mixture is from 0.001:1 to 0.3:1; from 0.5 to 2 wt.% of alkaline earth metal oxide; and one or more inert fillers. This composition is particularly suitable for the production of molded articles by injection molding.

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Maleo, Italy

Mario Bernasconi