An anticorrosive pigment comprising an aluminum polyphosphate comprises at least one cerium-based compound and/or one lanthanum-based compound and/or one praseodymium-based compound. An anticorrosive paint incorporating the pigment is also provided.

Antimicrobial chemical compositions comprise an aluminum phosphate (AlP) solid dispersed within a binding polymer, wherein one or more bioactive materials are disposed within AlP forming a bioactive-AlP complex. The complex may comprise the bioactive material chemically bonded with the AlP, physically combined with the AlP, or a combination of both. The complex may be formed according to precipitation, condensation and sol-gel methods of forming. The complex is engineered to provide a controlled delivery of the bioactive material or a constituent thereof upon exposure to moisture to give a desired level of antimicrobial resistance to a film or composite formed from the composition of at least about 30 g/m.sup.2, and may also provide a desired degree of corrosion resistance through the release of passivating phosphate anion. Such antimicrobial chemical compositions provide an improved degree of active, long-term resistance to a broad range of micro-organisms when compared to known antimicrobial chemical compositions.

A cathode active material for sodium batteries has excellent discharge capacity, and a sodium battery has the cathode active material for sodium batteries. A cathode active material for sodium batteries is represented by a general formula Na.sub.4Co.sub.(3-x)M.sub.x(PO.sub.4).sub.2P.sub.2O.sub.7; M is any of Fe, Cr, Mn and Al; X is 0.015x0.21 when M is Fe; X is 0.03x0.18 when M is Cr; X is 0.006x0.24 when M is Mn; and X is 0.03x0.06 when M is Al.

A cathode active material for sodium batteries has excellent discharge capacity, and a sodium battery has the cathode active material for sodium batteries. A cathode active material for sodium batteries is represented by a general formula Na.sub.4Co.sub.(3-x)M.sub.x(PO.sub.4).sub.2P.sub.2O.sub.7; M is any of Fe, Cr, Mn and Al; X is 0.015x0.21 when M is Fe; X is 0.03x0.18 when M is Cr; X is 0.006x0.24 when M is Mn; and X is 0.03x0.06 when M is Al.

An active material used for an electrochemical device utilizing Li ion conduction, and capable of improving cycle stability. The object is attained by providing an active material used for an electrochemical device utilizing Li ion conduction, including an active substance capable of absorbing and releasing a Li ion, and an Na ion conductor disposed on the surface of the active substance and having a polyanionic structure.

Polyphosphate compositions are produced by a process that includes the steps of continuously introducing a phosphate compound into a polymerization vessel, polymerizing the phosphate compound at a temperature of 250-450 C. for a time period sufficient to form the polyphosphate composition, and continuously discharging the polyphosphate composition from the polymerization vessel. The phosphate compound can be fed to the polymerization vessel in the form of an aqueous slurry containing 5-50 wt. % of the phosphate compound. Resulting polyphosphate compositions often contain at least 8 wt. % of a polyphosphate and less than 35 wt. % of the phosphate compound.

Polyphosphate compositions are produced by a process that includes the steps of continuously introducing a phosphate compound into a polymerization vessel, polymerizing the phosphate compound at a temperature of 250-450 C. for a time period sufficient to form the polyphosphate composition, and continuously discharging the polyphosphate composition from the polymerization vessel. The phosphate compound can be fed to the polymerization vessel in the form of an aqueous slurry containing 5-50 wt. % of the phosphate compound. Resulting polyphosphate compositions often contain at least 8 wt. % of a polyphosphate and less than 35 wt. % of the phosphate compound.