Abstract: This invention is directed to glass compositions particularly designed for use in rear projection tube applications. The glass compositions are essentially free from ZnO, PbO and other easily reducible metal oxides other than Sb.sub.2 O.sub.3 and are essentially colorless. The glasses exhibit essentially no browning discoloration upon being exposed to high voltage electrons, linear coefficients of thermal expansion (25.degree.-300.degree. C.) between about 97-100.times.10.sup.-7 .degree. C., annealing points not lower than about 475.degree. C., strain points not lower than about 440.degree. C., electrical resistivities expressed as Log R greater than 9 at 250.degree. C. and greater than 7 at 350.degree. C., and liquidus temperatures below about 1100.degree. C. The glass compositions consist essentially, expressed in terms of weight percent on the oxide basis, of______________________________________ SiO.sub.2 55-60 K.sub.2 O 5.75-10 Al.sub.2 O.sub.3 1-3 Na.sub.2 O + K.sub.2 O 10.5-14 ZrO.sub.2 0-3.5 K.sub.

Abstract: Plastic shrink tubes, when filled loosely with explosive powders, and sealed and heated to temperatures of about 300.degree. - 600.degree.F, will shrink and uniformly compress the powders contained therewithin along the length thereof to produce a powder of constant linear density useful in providing constant velocity detonations.