Abstract: A method of producing pigmented extrudates or mouldings from an unpigmented thermosetting moulding material, which comprises roughly blending a pigment component with an aminoplast moulding material substantially free from pigment and having an average particle size not greater than 150 microns, and completely dispersing the pigment compound through the aminoplast moulding material by progressing the rough blend through an extruder or injection moulding machine having a barrel grooved in accordance with German Offenlegungschrift No. 2514307, and extruding or injection moulding the resulting pigmented material.

Abstract: A screw-housing for an extruder or injection moulding machine, having a longitudinal bore on the internal surface of which is defined grooving, preferably in the form of a number of equidistantly spaced grooves, extending longitudinally throughout substantially the whole length of the housing or alternatively throughout a major portion of the length of the housing downstream of the feed zone thereof.

Abstract: Aminoplastic moulding compositions include a filler which comprises or consists of a cured particulate aminoplast material having a water absorption (absorbency) of less than 2 milliliters of water per gram; the aminoplast filler material preferably is a hydrophobic ureaformaldehyde foam which has been disintegrated prior to incorporation in the resin component of the composition.