Abstract: A purifier for nuclear reactor cooling water, which contains, as an active ingredient,a titanium oxide-based solid solution of the formula (1)(Ti.sub.1-x Al.sub.x)O.sub.2 (1)wherein x is defined by 0<x<0.5, and/oran aluminum oxide-based solid solution of the formula (2)(Al.sub.1-y Ti.sub.y).sub.2 O.sub.3 (2)wherein y is defined by 0<y<0.5, and a method of purification of nuclear reactor cooling water, which comprises bringing nuclear reactor cooling water having a temperature of 100.degree. to 300.degree. C. into contact with the above purifier.

Abstract: A process for the production of a magnesium oxide having high hydrolysis resistance and high fluidity, which comprises:(A) a step of reacting a water-soluble magnesium salt with an alkaline substance in such an amount that is not more than 0.95 equivalent weight based on 1 equivalent weight of the water-soluble magnesium salt, at a temperature of not more than 40.degree. C.,(B) a step of heating the resultant reaction product and its reaction mother liquor at about 50.degree. to 120.degree. C. to form a magnesium hydroxide,(C) a step of forming particles having an average secondary particle diameter of about 5 to 500 .mu.m by using a spray drier,(D) a step of firing the particles at about 1,100.degree. to 1,600.degree. C., and(E) a step of pulverizing the resultant fired product under conditions which do not substantially destroy the average secondary particle diameter obtained in the above step (C).

Abstract: A flame retardant produced by surface-treating magnesium hydroxide with a dialcohol amine salt of an alcohol phosphate ester represented by formula (1) ##STR1## wherein R represents an alkyl, alkenyl group or aralkyl having 10 to 30 carbon atoms, R' represents an alkylene group having 1 to 6 carbon atoms and n represents 1 or 2,and/or an alcohol phosphate ester or an alkali metal salt thereof represented by formula (2) ##STR2## wherein R and n represent the same meanings as in formula (1) and M represents an alkali metal and/or hydrogen, provided that when n=1, each of two M's may independently represent an alkali metal or hydrogen.and a resin composition containing the above flame retardant.

Abstract: A rust-proofing agent containing as an active ingredient an oxide solid solution represented by formula (1)[(Zn).sub.1-y (Mg).sub.y ].sub.1-x Al.sub.x O.sub.1+x/2 (1)wherein x denotes a positive number satisfying 0.1<x<0.6 and y denotes a positive number satisying 0<y<1, a rust-proofing coating composition containing said rust-proofing agent and a coating method for preventing or inhibiting corrosion of a metallic surface.

Abstract: A filiform corrosion-resistant primer coating composition for use in application to a metallic substrate, comprising a film forming component containing a film-forming resinous material and a hydrotalcite component, characterized in that the hydrotalcite component is a hydrotalcite solid solution represented by the following formula (1)[(Mg.sup.2+).sub.y1 (M.sup.2+) y2].sub.1-x M.sub.x.sup.3+ (OH).sub.2 A.sub.x/n.sup.n-.mH.sub.2 Owherein M.sup.2+ represents at least one divalent metal cation selected from the group consisting of Zn, Cd, Pb, Ca and Sr, M.sup.3+ represents a trivalent metal cation, A.sup.n- represents an anion having a valence of n, and x, y1, y2 and m represent positive numbers which satisfy the following conditions:0<x.ltoreq.0.5,0<y1,0<y2,0.5.ltoreq.y1+y2<1, and0.ltoreq.m<2,the amount of the hydrotalcite solid solution being 0.1 to 20 parts by weight per 100 parts by weight of the film-forming component.

Abstract: Magnesium oxide is incorporated into a polyvinyl chloride resin composition comprising a polyvinyl chloride, a hydrotalcite, a .beta.-diketone compound and an organic acid salt of zinc or a polyvinyl chloride resin composition comprising a polyvinyl chloride, a hydrotalcite and an organic tin compound. Bubbling as well as discoloration can be prevented in a molded article prepared from the polyvinyl chloride resin composition. Magnesium oxide having a specific surface area of at least 50 m.sup.2 /g and an average secondary particle size smaller than 5 .mu.m is preferably used.

Abstract: A fire-retardant resin composition comprising(A) 100 parts by weight of a member selected from the group consisting of the thermoplastic resins and the thermosetting resins,(B) about 1 to about 50 parts by weight of a halogen-containing organic fire retardant,(C) about 0.05 to about 10 parts by weight of a hydrotalcite having a BET specific surface area not exceeding about 30 square meters per gram, as a stabilizer, and(D) 0 to about 20 parts by weight of a fire-retarding assistant other than the fire retardant of (B), above.

Abstract: In a process for producing a polymer or copolymer of a vinyl chloride monomer with or without a comonomer by aqueous suspension polymerization or copolymerization in the presence of a suspension stabilizer and a polymerization initiator which is insoluble or sparingly soluble in water and soluble in the monomer; the improvement wherein the polymerization or copolymerization is carried out in the presence of, as said suspension stabilizer, a hydrotalcite compound of the following formulaM.sub.1-x.sup.2+ M.sub.x.sup.3+ (OH).sub.2 A.sub.x/n.sup.n-.mH.sub.2 O (1)wherein M.sup.2+ is at least one divalent metal cation, M.sup.3+ is at least one trivalent metal cation, A.sup.n- is an anion having a valence of 1 to 4, and x and m represent numbers satisfying the following expressions0<x<0.5 and 0.ltoreq.m<2.

Abstract: An agricultural film structure composed of a mixture of a thermoplastic resin and an infrared radiation-absorbing powdery inorganic compound, said mixture comprising(a) 100 parts by weight of a thermoplastic resin and(b) about 1 to about 20 parts by weight of a hydrotalcite powder, as the infrared radiation absorbing powdery inorganic compound, having an average secondary particle diameter of not more than about 5 microns and a BET specific surface area of not more than about 30 m.sup.2 /g and being represented by the following formula (1)M.sub.1-x.sup.2+ Al.sub.x (OH).sub.2 (A.sup.n-).sub.x/n mH.sub.2 O (1)wherein M.sup.2+ represents a divalent metal ion selected from the group consisting of Mg, Ca and Zn ions, A.sup.n- represents an anion having a valence of n, and x and m satisfy the following conditions0<x<0.50.ltoreq.m.ltoreq.2.

Abstract: A synthetic resin composition having reduced corrosion-causing tendency and coloration, said composition comprising (A) 100 parts by weight of a synthetic resin containing halogen and/or an acidic substance, and (B) 0.001 to 50 parts by weight of a hydrotalcite solid solution represented by the following formula (1)[(M.sub.1.sup.2+).sub.y1 (M.sub.2.sup.2+).sub.y2 ].sub.1-x M.sub.x.sup.3+ (OH).sub.2 A.sub.x/n.sup.n-.mH.sub.2 O . . . (1)wherein M.sub.1.sup.2+ represents at least one divalent metal cation, M.sub.2.sup.2+ represents at least one divalent metal cation, M.sup.3+ represents a trivalent metal cation, A.sup.n- represents an anion having a valency of n, and x, y1, Y2 and m are positive numbers represented by the following expressions0<x.ltoreq.0.5,0<y1,0<y2,0.5.ltoreq.y1+y2<1, and0.ltoreq.m<2; anda method for preventing the corrosion-causing tendency or coloration of a synthetic resin containing halogen and/or an acidic substance by using the above formula (1) compound.

Abstract: A method of purifying cooling water used in nuclear reactors, which comprises contacting said cooling water with a hydrotalcite compound of the following formulaM.sub.1-x.sup.2+ M.sub.x.sup.3+ (OH).sub.2 A.sub.x/n.sup.n-. mH.sub.2 O (1)wherein M.sup.2+ represents a divalent metal cation, M.sup.3+ represents a trivalent metal cation, A.sup.n- represents an anion having a valence of n, and x and m satisfy the following expressions0<x<0.50.ltoreq.m<1or a calcined product thereof obtained by calcination at a temperature of up to about 900.degree. C.; and a purifying agent used therefor.

Abstract: A hydrothermally treated product useful for treating an iron deficiency of a compound having a hydrotalcite-like crystal structure and represented by the following formula (I)(Fe.sup.2+,Mg.sup.2+).sub.x (Al.sup.3+,Fe.sup.3+).sub.2 (OH).sub.2x+6-nz (A.sup.n-).sub.z.mH.sub.2 O (I)wherein A.sup.n- represents an anion having a valence of n, Mg.sup.2+ is within the range of O.ltoreq.Mg.sup.2+ <x, Fe.sup.3+ is within the range of O.ltoreq.Fe.sup.3+ <2, x is a number represented by 1.ltoreq.x<20, z is a number represented by 0<z<3, and m is a number represented by 0.ltoreq.m<20, the product being formed by the thermal treatment of the compound of formula (I) at a temperature of about 100.degree. C. to about 200.degree. C. in an aqueous medium.

Abstract: An aluminum hydroxide gel of the following formula[CaO, MgO, M.sub.2 O].sub.x.Al.sub.2 O.sub.3.(CO.sub.2).sub.y.mH.sub.2 Owherein M represents an alkali metal, M.sub.2 O may be zero, CaO and MgO are not zero at the same time, and x, y and m are positive numbers represented by the following expressions0<x<1,0.2<y.gtoreq.1,2.gtoreq.m<10.Said aluminum hydroxide gel can be produced by reacting an aluminum compound soluble in water and/or lower alcohols with a carbonate ion yielding compound soluble in water and/or lower alcohols at a pH of about 6 to about 9.5 under such conditions that the CO.sub.2 /Al mole ratio of the resulting aluminum hydroxide gel is at least about 0.1, and ion exchanging the alkali metals of the resulting compound with magnesium and/or calcium. This invention also provides an antacid composition comprising said aluminum hydroxide gel as an active ingredient.

Abstract: A method for purifying cyclohexanone containing by-product organic acids and obtained by oxidation of cyclohexane, which comprises contacting said cyclohexanone with at least one treating agent selected from the group consisting of hydrotalcite compounds of the following formula (1)M.sub.x.sup.2+ M.sub.2.sup.3+ (OH).sub.2x+6-nz (A.sup.n-).sub.z.mH.sub.2 O (1)wherein M.sup.2+ represents a divalent metal ion, M.sup.3+ represents a trivalent metal ion, A.sup.n- represents an anion having a valence of n, and x, z and m represent numbers satisfying the following expressions1<x<20,0<z.ltoreq.2,0.ltoreq.m<20'and metal oxide-type solid solutions of the following formula (2)M.sub.1-x'.sup.2+ M.sub.x'.sup.3+ O.sub.1+1/2x' (2)wherein M.sup.2+ and M.sup.3+ are as defined with respect to formula (1), and x' is a number represented by 0<x'<0.5, and showing a powder X-ray diffraction pattern corresponding to M.sup.2+ O.

Abstract: A curable rubber composition composed of a halogen-containing rubber and at least one member selected from the group consisting of a vulcanizing agent and a vulcanization accelerator other than thiazole-type vulcanization accelerators is cured under heat in the presence of, as an acid acceptor, a calcinated product of a hydrotalcite compound of the following formulaM.sub.x.sup.2+ Al.sub.2 (OH).sub.2x+6-nz (A.sup.n-).sub.z.mH.sub.2 O (1)wherein M.sup.2+ represents at least one metal element selected from the group consisting of Mg and Zn, A.sup.n- represents an anion having a valence of n, m represents a positive number, and x and z represent positive numbers satisfying the following expressions12>x.gtoreq.2,z.ltoreq.2.The cured product has improved water resistance.

Abstract: A process for removing a halogen component from a halogen-containing organic compound, which comprises contacting an organic compound in the liquid state which is produced by using a halogen containing catalyst selected from the group consisting of Friedel-Crafts catalysts and Ziegler catalysts and contains the halogen component derived from said catalyst, with a hydrotalcite compound represented by the formulaM.sub.1-x.sup.2+ M.sub.x.sup.3+ (OH).sub.2+x-ny A.sub.y.sup.n-.mH.sub.2 OwhereinM.sup.2+ represents a divalent metal ion selected from the group consisting of Mg.sup.2+, Zn.sup.2+, Ca.sup.2+, Ni.sup.2+, Co.sup.2+, Mn.sup.2+ and Cu.sup.2+,M.sup.3+ represents a trivalent metal ion selected from the group consisting of Al.sup.3+, Fe.sup.3+ and Cr.sup.3+,A.sup.n- represents an anion having a valence of n selected from the group consisting of HCO.sub.3.sup.-, OH.sup.- and CO.sub.3.sup.2-, andx, y and m are each a positive number and satisfy the following conditions 0.1<x<0.5, 0.1<y<0.4, 0.ltoreq.

Abstract: A pharmaceutical composition comprising an amount, effective as an antacid, of a phosphate ion-containing hydrotalcite of the following formulaMg.sub.x Al.sub.2 (OH).sub.2x+6-n.sbsb.1.sub.z.sbsb.1.sub.-n.sbsb.2.sub.z.sbsb.2 (A.sub.1.sup.n.sbsp.1.spsp.-).sub.z.sbsb.1 (A.sub.2.sup.n.sbsp.2.spsp.-).sub.z.sbsb.2 .multidot.mH.sub.2 Owherein A.sub.1.sup.n.sbsp.1.spsp.- represents at least one anion having a valence of n.sub.1 selected from the group consisting of H.sub.2 PO.sub.4.sup.-, HPO.sub.4.sup.2.spsp.- and PO.sub.4.sup.-3, A.sub.2.sup.n.sbsp.2.spsp.- represents at least one anion having a valence of n.sub.2 other than the A.sub.1.sup.n.sbsp.1.spsp.-, and x, z.sub.1, z.sub.2, and m are positive numbers satisfying the following expressions2<x<40,0.05.ltoreq.z.sub.1 .ltoreq.2,0.1.ltoreq.z.sub.2 <2,0<m<40,0.5.ltoreq.z.sub.1 +z.sub.2 .ltoreq.

Abstract: A magnesium oxide having a cubic system needle-like crystal structure and a length-to-diameter ratio, determined by an electron microscope at a magnification of 10,000, of at least about 5; and a process for producing a magnesium oxide having a cubic system needle-like crystal structure, which comprises calcining a basic magnesium compound having a needle-like crystal structure expressed by the following formulaMg(OH).sub.2-nx A.sub.x.sup.n-.mH.sub.2 Owherein A.sup.n- represents a monovalent (n=1) to tetravalent (n=4) anion, x is 0.2.ltoreq.x.ltoreq.0.5, and m is 0<m.ltoreq.2,or a magnesium hydroxide having a needle-like crystal structure, at a temperature of not less than about 400.degree. C. to convert it to the magnesium oxide.

Abstract: Slaked lime (calcium hydroxide) is obtained by contacting quicklime (calcium oxide) with an aqueous solution containing at least one anion selected from the group consisting of Cl, Br and NO.sub.3 ions in a concentration of about 0.1 to about 5 mole/liter at a temperature of about 10.degree. C. to about 65.degree. C. Magnesium hydroxide can be produced by reacting the aforesaid slaked lime with magnesium chloride or magnesium nitrate in an aqueous medium, the amount of slaked lime being about 0.5 to about 0.95 equivalent per equivalent of the magnesium compound, and thereafter heat-trating the reaction product in an aqueous medium at a temperature of about 150.degree. C. to about 250.degree. C.

Abstract: An adsorbent composition consisting essentially of(i) about 5 to about 95% by weight of a hydrotalcite compound represented by the following formula (1)(M.sup.2+).sub.x Al.sub.2 (OH).sub.2x+6-ny (A.sup.n-).sub.y.mH.sub.2 O (1)whereinM.sup.2+ represents Mg.sup.2+ and/or Zn.sup.2+,A.sup.n- represents an anion having a valence of n, andx, y and m are numbers which satisfy the following conditionsx.gtoreq.1, 0<y<2, m>0,or a product of calcination at a temperature of up to about 800.degree. C. of said hydrotalcite compound, and(ii) about 95 to about 5% by weight of activated carbon.