Alkali metal silicate binder compositions
US4329177A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 27, 1980 |
| Grant date | May 11, 1982 |
| Priority date | — |
| Expiry date | Oct 27, 2000 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB22C1/26
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A binder composition in aqueous solution, suitable for use in the production of foundry sand moulds and cores is obtained by mixing PA1 (i) an alkali metal silicate PA1 (ii) a substantially water soluble carbohydrate selected from monosaccharides, disaccharides, polysaccharides and derivatives thereof and PA1 (iii) urea. The composition may also contain an oxyanion such as a borate which is capable of forming a water soluble complex with the carbohydrate. The preferred carbohydrate is a stabilized starch hydrolysate whose reducing power has been removed by a process such as hydrogenation. Moulds and cores bonded using the composition may be hardened by injection of carbon dioxide gas, or a chemical hardening agent for the alkali metal silicate may be added to the sand.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.