摘要 |
Irregular shaped particles of cross-linked copolymer of styrene-divinylbenzene in which essentially 90% or more of the particles pass through a 100 mesh screen (U.S. Sieve Series) and essentially 50% pass through a 200 mesh screen (U.S. Sieve Series) is produced by high speed attrition milling of relatively inexpensive large-sized copolymer beads. The resulting particles are irregularly shaped cross-linked copolymer particles which are desirable and useful as a filler material for investment casting waxes. The small-sized irregularly-shaped cross-linked copolymer beads produced by high speed attrition milling essentially eliminate any "orange peel" effect on wax pattern surface and also results in improved packing of the wax composition thereby producing high quality precision parts more readily than heretofore possible.
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