Production of foamed gypsum moldings

US4043825A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Martin Muller · Berlin, DE
• Friedrich Hinsche
• Gerhard Winter · Dossenheim, DE
• Karl Brandle

Key dates

• Filing date: Aug 14, 1975
• Grant date: Aug 23, 1977
• Expiry date: Aug 14, 1995

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C04B28/14
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

In the production of a gypsum-based porous body of high strength by foaming a gypsum-water mixture containing alkali, hydrogen peroxide and a decomposition catalyst therefor, the improvement which comprises including in said mixture an acid-reacting compound with active hydrogen atoms in a quantity insufficient for complete neutralization of the alkali. The alkali is preferably calcium and/or magnesium oxide and/or hydroxide and the preferred acid-reacting compounds are phosphates and/or sulfates, especially potassium hydrogen phosphates. The acid-reacting compound is employed in an amount sufficient to neutralize about 5 to 50% of the alkali, the final pH being about 12 to 12.5.