Abstract: The polypropylene-based thermoplastic fibers are uniform in cross-section, not having any degraded surface skin, and they are heat-weldable at a pressure at a temperature which is lower than the melting temperature, by virtue of internal heating due to the effect of said pressure. They are made of a first constituent with high crystallinity and at least one second constituent, compatible with the first constituent, and of crystallinity that is lower than that of the first constituent. They have a quantity of primary oxidation inhibitor lying in the range 350 ppm to 1000 ppm. Such fibers are made by spinning under conditions that avoid molecular degradation by thermal oxidation at the periphery of the fibers, in particular with cooling that is rapid immediately on leaving the extrusion head. The non-woven fabric obtained by heat-bonding such fibers is characterized by weld points that are in the form of a polymer laminate that is uniform and transparent.

Abstract: Apparatus and method for molding generally cubical building modules of concrete, the apparatus comprising both internal and external movable mounted molding components and preferably including mechanisms for advancing the components into molding positions and for withdrawing the components from the molding position upon completion of the molding of a module. The method involves the use of such molding components and contemplates certain sequences in the advancement and withdrawal of the molding components for different portions of the modules.

Abstract: A non-skid device in which the road engaging part is a long flexible member formed of one or more twisted steel wire cables embedded in a thick coating of rubber and in which said road engaging part, when on a tire, extends back and forth zigzag fashion diagonally across the tread of the tire and is secured in place on the tire by two belt type anchor members which are positioned respectively at opposite sides of the tire. The anchor member at the inner side of the tire has readily detachable parts which, when detached, allow the non-skid member to be applied to a tire from the outer side of the wheel without using a jack to lift the wheel. Means is provided for tightening the non-skid device on a tire after it is applied thereto. The flexible zigzag road engaging parts have good non-skid qualities and have longer life than metal cross chains when used on bare pavements.