Aqueous solutions of alkali polysilicates

US4120938A · kind A · utility

Assignee

• Dynamit Nobel GmbH · DE

Inventors

• Rainer Haase · Nortorf, DE
• Volker Hunger
• Arnold Lenz · Kornwestheim, DE

Key dates

• Filing date: Jul 8, 1976
• Grant date: Oct 17, 1978
• Expiry date: Jul 8, 1996

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B27K3/52
• WIPO field: Textile and paper machines
• WIPO sector: Mechanical engineering

Abstract

A process for the preparation of an aqueous alkali metal polysilicate solution having an SiO.sub.2 : alkali metal oxide mole ratio of 2.5 - 5.5 : 1 and a silica content of 16 - 23% by weight which comprises contacting a tetraalkoxysilane of the formula Si(OR).sub.4 wherein each R is independently a straight or branched-chain alkyl group of 1 to 3 carbon atoms with an aqueous alkali metal hydroxide solution at a temperature between room temperature and the boiling point of the reaction mixture and at a temperature up to 100.degree. C. distilling over alcohol formed by the reaction of the silane with the alkali metal hydroxide.