| 摘要 |
A method of producing flammable briquettes, moulding sands and core sands with the participation of a specially prepared binder composed of acid hardening agent and a basic resin, characteristic in that: 100 parts by weight of a loose material is mixed with 0.7-22 parts by weight of acid resin - a hardening agent, obtained through the condensation, in the presence of an acid or maleic acid anhydride, of a basic resin which contains methyl groups or methylol groups etherified with methanol with polyhydroxy alcohols with various grades of purity such as ethylene glycol, neopentyl glycol, glycerine, trimethylolpropane and/or with sugar and/or with molasses, or is mixed with 0.7 - 0.22 parts by weight of acid resin - a hardening agent, obtained through the condensation, in the presence of an acid, of formalin solution and/or urea-formaldehyde concentrate, polyhydroxy alcohol with various grades of purity such as ethylene glycol, neopentyl glycol, glycerine, trimethylolpropane, solutions of polyhydroxy alcohols and urea, molasses. Further, the loose material mixed with the hardening agent, or simultaneously the components, are mixed with basic resins such as urea-formaldehyde resin, phenolic-formaldehyde resin, urea-formaldehyde-furan resin, urea-formaldehyde-phenol resin in the amount of 0.8-22 parts by weight; next, it is formed and cold hardened or dried at a temperature not exceeding 155 degrees C. |
