Abstract: A powdered leather which is composed of at least 85% by weight of cortex, at most 2% by weight of oil and fat, and at most 0.5% by weight of Na.sup.+ and Ca.sup.2+ ions capable of being eluted by water and which has an average particle size (D.sub.50) of at most 7 .mu.m, a standard deviation of the average particle size being at most 3 .mu.m. With this powdered leather, it is possible to thin films, coatings, fibers, etc. which would hardly be deteriorated with time.

Abstract: The invention provides a method for the preparation of a sheet of a crystalline thermoplastic resin, e.g. polypropylene, having excellent transparency and surface properties as well as thermoformability. The inventive method comprises quenching of a molten resin sheet extruded out of a T-die by introducing the same into a slit where cooling water is flowing at a velocity higher than the running velocity of the extruded molten resin sheet and then stretching the thus quenched resin sheet in a stretch ratio in the range from 1.02 to 1.5 times.

Abstract: A method of producing a biaxially oriented sheet or film, wherein molten resin is simultaneously, biaxially oriented in a direction of extruding the molten resin and in a direction perpendicular thereto, and an apparatus therefor, are disclosed. In the method of producing a biaxially oriented sheet or film, the molten resin is extruded into a tubular form in the horizontal direction, once cooled, thereafter, in heating the tubular resin prior to the biaxial orientation, the tubular resin is uniformly heated with the heating applied on the vertically lower side and the heating applied on the vertically upper side of the tubular resin being controlled separately of each other so as to prevent the ununiformity of the heating of the tubular resin in the circumferential direction thereof due to the elevation in heat caused by a thermal convection phenomenon, and then, the tubular resin is biaxially oriented.

Abstract: A molding material having superior buffering character, moldability and dimensional stability obtained by incorporating a copolymer composed predominantly of polyethylene or ethylene with an inorganic filler blend comprising sand with an average particle size of 100 to 500 microns and calcium sulfite, and foaming the resulting composition. A molded product having a lustrous and beautiful superficial coating can be obtained by pressing the aforementioned foamed body while it is still hot against a smooth cool solid surface and cooling the foamed body down to a temperature below its softening point. Further, the aforementioned molding material is useful for packings, mattresses and lightweight construction materials.

Abstract: An oil adsorbent comprising a plastic material for eliminating oils present in or on the surface of water through adsorption. Said adsorbent is produced by foaming by a physical means polyethylene containing 30-80% by weight of at least one inorganic calcium compound selected from the group consisting of calcium sulfite and calcium carbonate, to prepare a foamy substance having a density of 0.06-0.10 g/cc and then shaping the substance to have a network structure.