Abstract: An object of the present invention is to provide an aluminum phospite having spherical shape. An aluminum phosphite of the present invention has the following formula. Alx(OH)y(HPO3)3·zH2O wherein: x represents 2.01 or more and 2.50 or less, y represents 0.03 or more and 1.50 or less, and z represents an integer of 0 to 4, respectively.

Abstract: An object of the present invention is to provide an aluminum phospite having spherical shape. An aluminum phosphite of the present invention has the following formula. Alx(OH)y(HPO3)3.zH2O wherein: x represents 2.01 or more and 2.50 or less, y represents 0.03 or more and 1.50 or less, and z represents an integer of 0 to 4, respectively.

Abstract: Valuable substances are recovered from a spent electroless nickel plating solution containing a water-soluble nickel salt, organic complexing agent, hypophosphite, phosphite, and alkali metal ion by adding oxalic acid to the plating solution for causing a nickel ion to precipitate as nickel oxalate for removal and recovery; optionally adding a sulfide to the plating solution for causing a heavy metal ion to precipitate as a heavy metal sulfide for removal; adding a mineral acid and calcium oxide, calcium hydroxide, calcium carbonate, calcium sulfate, calcium chloride or a calcium salt of organic acid to the plating solution from which the nickel ion has been removed; firing solids of the solution in air for converting the alkali metal ion into an alkali metal salt of mineral acid, converting phosphorus into hydroxyapatite, and pyrolyzing off the organic material; and pouring a solid mixture of the alkali metal salt of mineral acid and hydroxyapatite into water for dissolving the alkali metal salt of mineral a

Abstract: A dental impression paper tray comprising a material mainly composed of pulp which is compressed molded to a dental impression tray shape having a thickness of 0.5-10 mm. Minute concavities/convexities may be formed at least on the inner surface of the paper dental impression tray. Paraffin wax may be dispersingly included in the tray or coated on the surface of the tray. A handle of the tray may be integrally attached to a dish portion by insertion or adhesion. Since the tray is made of paper and is less expensive, it can be domestically disposed with an incinerator as a disposal tray. Further, the tray having the minute concavities/convexities has an increased holding force to an impression material. The tray to or in which paraffin wax is coated or contained has increased water resistance.

Abstract: The present invention provides a lubricant composition for metalworking at a temperature higher than 200.degree. C. which comprises as its active components (i) at least one alkali metal salts of phthalic acid and (ii) a glass composition comprising 20 to 70% by weight of P.sub.2 O.sub.5, 8 to 72% by weight of M.sub.2 O wherein M is an alkali metal and 0 to 80% by weight of B.sub.2 O.sub.3, the ratio of component (i) to component (ii) being about 10:90 to about 90:10 in a total amount of 100 parts by weight.

Abstract: The present invention provides a releasing lubricant for use in forging and extrusion processes.In one embodiment, the lubricant comprises a mixture of:(a) at least one compound selected from the group consisting of phosphoric acid and its salts,(b) at least one compound selected from the group consisting of boric acid and its salts,(c) at least one compound selected from the group consisting of alkali metal carbonates, nitrates, sulfates and hydroxides, and(d) a phyllosilicate,wherein the amounts of the compounds (a) to (c) (as oxides) are: 14 to 55 molar % of P.sub.2 O.sub.5, 0 to 80 molar % of B.sub.2 O.sub.3 and 30 to 80 molar % of M.sub.2 O (M being an alkali metal) and the total amount of these compounds is 91 to 99.5 wt. % or 0.5 to 39 wt. % based on the solid.In another embodiment, the amounts of the compounds (a) to (c) (as oxides) are: 14 to 39.5 molar % of P.sub.2 O.sub.5, 0 to 80 molar % of B.sub.2 O.sub.3 and 30 to 80 molar % of M.sub.