Abstract: A colorant composition comprising finely distributed colorants and a plurality of polyolefin waxes, wherein a metallocene polyolefin wax having a viscosity in the rant from 3000 to 80000 mPa·s and optionally further waxes, for example polar or nonpolar non-metallocene polyolefin waxes or homo- and/or copolymers of ethylene and/or propylene are present. All polyolefin waxes together make up at least 50% by weight of the formulation and melt in the temperature range between 50 and 170° C. The inventive colorant composition has reduced dusting and is used for the production of colored plastics parts.

Abstract: Colorant composition finely divided colorants and two or more polyolefin waxes, the quantitatively greater fraction representing a metallocene wax, and the further waxes being polar or a polar non-metallocene-polyolefin waxes or copolymers of ethylene. All of the polyolefin waxes together make up at least 15% by weight of the formula, and melt between 70 and 15O0 C. The colorant composition of the invention features reduced dust and is used for masterbatch production.

Abstract: An external combustion engine (1) comprising pressure vessel means defining a tubular working chamber (3) having spaced apart first and second ends and including first wall means (11), adjacent the first end of the chamber, heated by heating means (10, 11) and second wall means (6), adjacent the second end of the chamber, cooled by cooling means. The engine further has a porous piston or regenerator (7) provided with heat exchanging means (9) and movable within the tubular working chamber (3) between the first and second ends of the chamber so that the working fluid passes through the heat exchanging means. The regenerator (7) has valving means.

Abstract: A colorant composition consisting essentially of one or more colorants finely dispersed in an amorphous poly-.alpha.-olefin which is composed of at least two different monomers having a butene-1 content of at least 25% by weight and melts at between 70.degree. and 150.degree. C., and a free-flow agent provides the way to dust-free colorant compositions for masterbatch production, the production of compounds and the direct coloration of plastomers and elastomers.