Patent · US Expired

D,L Tartaric acid as retardant for gypsum plaster

US4094693A · kind A · utility

6Cited by

5References

8Claims

0Family size

Assignee

Deutsche Gold- und Silber-Scheideanstalt Vormals Roessler

Inventors

Helmut Knorre · Seligenstadt, DE
Manfred Langer · Hanau, DE
Peter Leidl

Key dates

Filing date	Sep 14, 1976
Grant date	Jun 13, 1978
Priority date	—
Expiry date	Sep 14, 1996

Classification

Technology area (CPC C)Chemistry; Metallurgy
CPC primaryC04B2103/20
WIPO fieldMaterials, metallurgy
WIPO sectorChemistry

Abstract

Industrial gypsum plaster (plaster of Paris) having a delayed setting time is prepared by including D,L-tartaric acid and sufficient calcium hydroxide that a 5 weight % aqueous suspension of the plaster has a pH of at least 11.5.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.