Abstract: A polyurethane integral hard foam construction panel comprises a denser edge zone and a porous core, the surface of the construction panel being enameled, and is used as a roofing plate, in particular as a small format, nailed roof cover plate.For that purpose the invention provides that the polyurethane integral hard foam of the construction panel includes fillers, namely 1 to 65% by weight flame-retardants such as aluminum hydroxide [Al(OH).sub.3 ] and/or Exolite and 1 to 90% slate powder.

Abstract: A primer is provided as a bonding base in an extruded hollow aluminum shape ensheathed by a polyurethane foam. Due to the different coefficients of expansion between the plastic and the aluminum, changes in length take place, which cannot be adequately prevented using the known primers.The invention therefore solves the problem to widely prevent the shrinkage of the plastic sheath and simultaneously to provide a way of depositing the primer in a simple manner.This problem is solved by the invention in that the primer is a compound of resin, pigment and acid. The purpose of the acid is to cause the bonding reaction with the metal substrate, whereas the pigments on one hand cause the bonding reaction with the plastic sheath and on the other hand are used to ascertain the apparent film thickness.An improvement in adhesion of 1,000% is surprisingly achieved when using such a primer.

Abstract: A process for producing propellant charge powders from solvent-containing mixtures such as nitroguanidine powders containing nitrocellulose and/ or nitrocellulose and diglycol dinitrate or nitroglycerin and nitroguanidine and additives wherein an alcohol-containing mixture or optionally a water-containing mixture of said propellant charge powders is premixed with additional components of the propellant powder, the mixture is first dried, if necessary, and the solvent is incorporated therein and the solvent-containing premix is homogenized and preplasticized in a kneading device or the water-containing premix is homogenized and preplasticized in the kneading device and then the resultant mixture is dewatered by drying and then combined with a solvent; then the solvent-containing mixture is plasticized in an extruder and converted thereby into granular form and the resulting granular material is extruded into a final product form in a screw-type extruder. Subsequently, the solvent is evaporated therefrom.