Water soluble thermoplastic printed wiring board spacer

摘要

A water soluble thermoplastic wiring board spacer for temporarily supporting an electrical component in fixed spaced relation to a printed wiring board which comprises a toroidally shaped spacer composed of a water soluble injection molded thermoplastic material. The material is preferably a polymer and the preferred polymer is a blend of partially hydrolyzed polyvinyl alcohol resin and fully hydrolyzed polyvinyl alcohol resin. The spacer has a melting temperature determined by the ratio of partially hydrolyzed polyvinyl alcohol resin to fully hydrolyzed polyvinyl alcohol resin and a solubility rate in water determined by the ratio of partially hydrolyzed polyvinyl alcohol resin to fully hydrolyzed polyvinyl alcohol resin. The spacer can have a plurality of spaced apart ridges and recessed surfaces on a surface thereof.