Process and binder for the manufacture of ceramic shells for use as molds

US5391341A · kind A · utility

Assignees

• Heinrich Ballewski · DE
• Herbert Graf · DE
• Wolfgang Grossmann · DE

Inventors

• Heinrich Ballewski · Neukirchen-Vluyn, DE
• Herbert Graf · Moers, DE
• Wolfgang Grossmann · Moers, DE

Key dates

• Filing date: Jan 17, 1992
• Grant date: Feb 21, 1995
• Expiry date: Jan 17, 2012

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C04B2235/96
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

For the manufacture of quickly drying dip coats whose drying time is comparable to the drying time of shells produced on the basis of alcoholic binders, the process uses as a binder for the dip a dispersion of aqueous colloidal silica sol to which synthetic high polymers and/or an emulsion from the group of silicon-organic compounds is formed which after drying is impermeable to water but permeable to water vapor.