| 摘要 |
<p>Hardener for casting mould and core mfr. using liquid, self-hardening water-contg. moulding composns. consisting of quartz sand with added sulphite waste liquor as binder hardeners and foaming agents, contains water-soluble inorganic Cr (VI) cpds and/or peroxydisulphates in combination with water-soluble inorganic Cu-, Fe- or Al salts. Pref. composn. contains, in wt. pts. 92-100 quartz sand, 0-8 refractory clay, 3.5-8 sulphite waste liquor with 45-55% solids, 0.1-0.6 foaming agent, 0.1-1.5 hardener, 0.1-2 Cu, Fe r Al salt, water up to 5.</p> |
