Abstract: A three-component tray-type packaging unit for semiconductor wafers, compatible with automatic equipment, includes a wafer carrier enclosed between a tub-shaped lower portion for receiving the wafer carrier and a matching lid. The wafers are fixed at four contact points-namely, in the wafer carrier by two rows of spring tongues arranged tangentially with respect to the wafer, and in the matching lid by two rows of inwardly projecting retention cones.

Abstract: A stackable, tray-type packaging unit for semiconductor discs, having a lr portion accommodating the discs and a matching lid, comprising two upright, elongated side walls in the lower portion and two narrow end walls, all walls as well as the lid consisting of deep-drawn plastic material inert to the disc material. A plurality of ribs are formed opposite to each other on the side walls, serving as guide means for the discs during the loading of the unit, stabilizing ribs for accommodating the discs are provided in the base of the lower portion on the joining line between opposite guide ribs. The lower part of the side walls are curved inwardly at an angle of 30.degree. to 60.degree. with respect to the perpendicular upper part.

Abstract: A process for the production of a pulverulent, tricklable mixture of ethylene/vinyl acetate copolymer and polyvinylchloride comprising the steps of mixing a mixture consisting essentially of (a) an ethylene/vinyl acetate copolymer having an acetate content of from 15% to 75% by weight, (b) powdery polyvinylchloride, in a mixture ratio of (a) to (b) of 1:3 to 2:1, and (c) from 0 to 5% by weight of the mixture of additives customary for polymer processing, in a high-speed mixture at temperatures above the softening temperature of said polyvinylchloride and below 170.degree. C., for a time sufficient to effect homogenization, quenching said homogenized mixture with water and removing the water, grinding the quenched product with the addition of from 0.5 to 10 parts by weight of an inert powder having particles in the submicroscopic range, in a high speed mill under passage of an airstream which is heated by friction, and recovering said pulverulent, tricklable mixture; as well as the powdery mixture so produced.