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AssigneeCentral Glass Company, Limited
InventorsIsami Fujioka, Kazutoshi Imada, Motoyasu Nishimura, Takayuki Ishibashi
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A nonexplosive chemical composition for gently and noiselessly breaking a rock or concrete mass. The composition comprises a principal component which is prepared by calcining a starting mixture comprising 100 parts by weight of quick lime and 1-20 parts by weight of calcium fluoride. In rock or concrete breaking operations, this composition in the form of aqueous slurry is poured into drill-holes and left to spontaneously hydrate and set with development of expansion pressure. For adequate retardation of the hydration, preferably a second fluoride such as Na.sub.2 SiF.sub.6 which gives CaF.sub.2 by reaction with CaO at the calcination temperature is added to the starting mixture. As an alternatively preferable method for the same purpose, an amino acid compound and/or a lignosulfonate is used as a hydration retarding agent which is mixed with the calcined principal component. Various auxiliary agents may optionally be added to this composition.
A chemical composition for gently breaking a rock or concrete mass, the composition comprising a principal component which is prepared by calcining a starting mixture comprising 100 parts by weight of quick lime, 1 to 20 parts by weight of calcium fluoride and an additional fluoride which gives CaF.sub.2 by reaction with CaO, said calcining performed at a temperature of from about 800.degree. C. to about 1400.degree. C. to produce a sintered starting mixture;
A chemical composition for gently breaking a rock or concrete mass, the composition comprising a principal component which is prepared by calcining a starting mixture comprising 100 parts by weight of quick lime and 1 to 20 parts by weight of calcium fluoride at a temperature of from about 800.degree. C. to about 1400.degree. C. to produce a sintered starting mixture, said composition further comprising a hydration retarding agent which is selected from the group consisting of glycine, alanine, valine, leucine, aspartic acid, glutamic acid, lysine, arginine, methionine, cystine, cystein and phenylalanine, and salts thereof, in amounts to up to 10% by weight of said principal component.
Dependencies are inferred from the claim text.