RTV silicone impression compsns. - contg. pptd. aluminium hydroxide filler, esp. for dental applications

摘要

Al(OH)3 obtd. by the wet pptn. process is used as filler in room temp. vulcanising (RTV) silicone impression materials based on a siloxanol paste and a hardener. Pref. the siloxanol oil is a condensable alpha,omega-dihydroxypolydiorganosiloxane, esp. as alpha,omega-dihydroxypolydimethylsiloxane with a viscosity of 1000-80000cP/20 degrees C. The base paste may also contain other known fillers and mineral oils as plasticiser. The pptd. Al(OH)3 has excellent oil uptake properties and gives stable pastes with RTV siloxanol oils which do not suffer from sepn. phenomena. The filler does not affect the curing reaction of the material, so that it cures rapidly after mixing with the hardener to give stable elastomeric prods. with good mechanical properties. The compsns. are esp. useful for taking dental impressions.