Abstract: An improved process for preparing pulverulent coating compositions pigmented with titanium dioxide and based on polyamides having at least ten aliphatically bound carbon atoms per carbonamide group using the precipitation method. The titanium dioxide pigments used are without nucleating effects or only have weak nucleating effects on the polyamide precipitation. The pigments have nucleating effects less than or equal to 3.degree. C. where .DELTA.T=(T.sub.max p)-(T.sub.o). T.sub.max p is the maximum temperature at which precipitation takes place in a solution of polyamide having pigment therein and T.sub.o is the maximum temperature at which precipitation takes place in polyamide solution having no pigment therein.

Abstract: The invention concerns an improved precipitation process in the manufacture of coating powders based on polyamides having at least ten aliphatically bound carbon atoms per carbonamide group. Rapid cooling takes place with stirring mainly by distilling the ethanol solvent until the temperature of precipitation is set in the range from 90.degree. to 113.degree. C. With the beginning of the saturation limit (about 125.degree. C.), the temperature difference between the coolant in the jacket and the solution inside is maintained at most at .+-.3.degree. C. The solution is maintained during the precipitation stage at constant temperature (isothermal procedure) by further distillation of the ethanol.

Abstract: The process and device in accordance with the present invention allow the simple and economic manufacture of printed circuit boards, wherein the metal of the conductors as well as the one covering the hole walls is identical with the metal being etched away from the areas between the conductors.According to this process, a one-or two-sided metal-coated base material is used which, upon production of the hole pattern, is provided in a known manner with a metal layer of desired thickness, covering the surface of the metal foil as well as the hole walls. Subsequently, a masking layer is applied by screen printing a positive image of the desired circuit pattern on the surface(s). In the following process step, the holes are filled with an ink by means of a screen printing stencil. In accordance with one embodiment of the invention, the ink used forms an etch-resistant surface film when drying. Upon etching, the masking layer as well as the surface film and the hole fillings are removed with a suitable solvent.