This application relates to a treating method for magnesium oxysulfate cement (MOS) or magnesium oxychloride cement (MOC) articles. The MOS or MOC article is molded, cured and dried, then the article is treated in water soluble phosphate solution for periods of 0.5 to 90 minutes. When the MOS or MOC article is treated in water soluble phosphate solution, phosphate can penetrate into MOS or MOC article, react with the non-active magnesia remaining in MOS or MOC article to form magnesium phosphate cement (MPC). After such treatment, MOS or MOC phase is bonded by magnesium phosphate cement (MPC), many defects for MOS or MOC article, such as cracks, distortion, chalking, effloresce, poor durability, and so on, can be reduced or eliminated.

This application relates to a treating method for magnesium oxysulfate cement (MOS) or magnesium oxychloride cement (MOC) articles. The MOS or MOC article is molded, cured and dried, then the article is treated in water soluble phosphate solution for periods of 0.5 to 90 minutes. When the MOS or MOC article is treated in water soluble phosphate solution, phosphate can penetrate into MOS or MOC article, react with the non-active magnesia remaining in MOS or MOC article to form magnesium phosphate cement (MPC). After such treatment, MOS or MOC phase is bonded by magnesium phosphate cement (MPC), many defects for MOS or MOC article, such as cracks, distortion, chalking, effloresce, poor durability, and so on, can be reduced or eliminated.

The invention describes a phosphate-based inorganic binder obtained by reaction between at least one basic constituent and an acidic phosphate salt, in the presence of a retarder which is an X.sup.+A.sup. salt, the solubility of which in an aqueous medium, measured at 25 C., is greater than that of the acidic phosphate salt, and in which: X.sup.+ is a cation chosen from alkali metals, alkaline earth metals, zinc, aluminium and the ammonium ion, and A.sup. is an acetate, formate, benzoate, tartrate, oleate, oxalate, bromide or iodide anion.

The present invention relates to a thermal emissivity coating composition comprising: a) an emissivity agent in an amount from 30 to 65% by weight with respect to the total weight of the thermal emissivity coating composition; b) a filler selected from the group consisting of oxides of aluminum, silicon, magnesium, calcium, boron and mixtures of two or more thereof, in an amount from 10 to 35 wt % with respect to the total weight of the thermal emissivity coating composition; and c) a binder in an amount from 12 to 52 wt % with respect to the total weight of the thermal emissivity coating composition; wherein the emissivity agent comprises cobalt oxide in an amount from 10 to 25 wt %, preferably 12 to 25 wt % with respect to the total weight of the thermal emissivity coating composition and further comprises chromium oxide and titanium oxide.

The invention describes a phosphate-based inorganic binder obtained by reaction between at least one basic constituent and an acidic phosphate salt, in the presence of a retarder which is an X.sup.+A.sup. salt, the solubility of which in an aqueous medium, measured at 25 C., is greater than that of the acidic phosphate salt, and in which: X.sup.+ is a cation chosen from alkali metals, alkaline earth metals, zinc, aluminium and the ammonium ion, and A.sup. is an acetate, formate, benzoate, tartrate, oleate, oxalate, bromide or iodide anion.

A composition of matter and method of forming a radiation shielding member at ambient temperatures in which the composition of matter includes a cold-fired chemically bonded oxide-phosphate ceramic cement matrix; with one or more suitably prepared and distributed radiation shielding materials dispersed in the cold-fired chemically bonded oxide-phosphate ceramic cement matrix.

A composition of matter and method of forming a radiation shielding member at ambient temperatures in which the composition of matter includes a cold-fired chemically bonded oxide-phosphate ceramic cement matrix; with one or more suitably prepared and distributed radiation shielding materials dispersed in the cold-fired chemically bonded oxide-phosphate ceramic cement matrix.

The method disclosed includes: a step (I) of preparing a dispersion liquid (S) including an aluminum compound (A); a step (II) of mixing the dispersion liquid (S) and a predetermined phosphorus compound (B) so as to prepare a coating liquid (U); a step (III) of applying the coating liquid (U) onto the base (X) so as to form a precursor layer of the layer (Y); and a step (IV) of subjecting the precursor layer to heat treatment at a temperature of 110 C. or more so as to form the layer (Y). The aluminum compound (A) can be formed by adding an acid to a solution including an aluminate. The number of moles (N.sub.M) of aluminum atoms derived from the aluminum compound (A) and the number of moles (N.sub.P) of phosphorus atoms derived from the phosphorus compound (B) satisfy 0.8(N.sub.M)/(N.sub.P)4.5.

The method disclosed includes: a step (I) of preparing a dispersion liquid (S) including an aluminum compound (A); a step (II) of mixing the dispersion liquid (S) and a predetermined phosphorus compound (B) so as to prepare a coating liquid (U); a step (III) of applying the coating liquid (U) onto the base (X) so as to form a precursor layer of the layer (Y); and a step (IV) of subjecting the precursor layer to heat treatment at a temperature of 110 C. or more so as to form the layer (Y). The aluminum compound (A) can be formed by adding an acid to a solution including an aluminate. The number of moles (N.sub.M) of aluminum atoms derived from the aluminum compound (A) and the number of moles (N.sub.P) of phosphorus atoms derived from the phosphorus compound (B) satisfy 0.8(N.sub.M)/(N.sub.P)4.5.

Disclosed is a method of fabricating a construction element. The method may include assembling a mold on a rotational casting machine; rotating the mold around at least two axes at a predetermined speed; providing a first portion of magnesium silico-phosphate cement (MSPC) mix, having an altered hardening rate, to the mold while rotating the mold until at least a portion of the mold's walls is covered by a first layer of the MSPC mix; and rotating the mold until the MSPC mix is hardened to a predetermined degree.