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Immordino et al. (45) Date of Patent: Mar. 12,2002
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OTHER PUBLICATIONS
Chemical Abstract No. 105:28885, abstract ol Hungarian Patent Specification No. 34528 (Mar. 1985).*
* cited by examiner
Primary Examiner—Anthony Green
(74) Attorney, Agent, or Firm—Greer, Burns & Crain, LTD; John M. Lorenzen; David F. Janci
(57) ABSTRACT
A plaster mixture for forming a machinable composition, includes calcium sullate hemihydrate; an internal lubricating dispersable binder, and an adhesive binder for adhering the plaster mixture to a substrate. In the prelerred embodiment, the composition includes calcium sullate hemihydrate, a poly(ethylene glycol) internal binder, and an ethylene/vinyl acetate copolymer adhesive binder.
26 Claims, 4 Drawing Sheets
