Dustfree investment material for accurately fitting cast pieces and method of producing these investment materials

摘要

Dustfree investment materials, for the production of accurately fitting cast parts, are described which contain water-soluble phosphates, magnesium oxide and silicon dioxide. The investment material is made up of two components (a) and (b) and component (a) contains the entire magnesium oxide, optionally a part of the silicon dioxide and, in the presence of silicon dioxide, 0.4 to 6% by weight of a hydrophile, organic solvent, and component (b) contains the phosphate, the remainder of the silicon dioxide and at least 0.5% by weight water.