Abstract: The present invention relates to a process for producing coated bismuth vanadate yellow pigments comprising the following steps:(a) subjecting a reaction mixture comprising a suspension in nitric acid of bismuthyl nitrate and vanadium (V) oxide, or a suspension in nitric acid of bismuth (III) oxide and vanadium (V) oxide, to stirring to form bismuth vanadate particles;(b) terminating the stirring and holding the reaction mixture for a period of time;(c) filtering off the bismuth vanadate particles;(d) washing the bismuth vanadate particles;(e) dispersing the washed bismuth vanadate particles in a hot, phosphate-containing, aqueous solution to activate the surface of the particles;(f) filtering off the activated bismuth vanadate particles;(g) washing the activated bismuth vanadate particles;(h) dispersing the activated bismuth vanadate particles in water to form a suspension;(i) precipitating at least one material selected from the group consisting of hydrated aluminum phosphate, aluminum/zinc phosphate or sil

Abstract: The invention relates to a process for re-processing deactivated DENOX catalysts on the basis of Ti/V/Mo/W mixed oxides.

Abstract: Enamel frit powder for electrostatic application with a surface resistance greater than 10.sup.16 ohms containing alkaline oxides and alkaline oxides wherein the weight ratio of the alkaline oxides Na.sub.2 O:K.sub.2 O and the weight ratio of the alkaline earth oxides CaO:BaO is each about 1:1, containing______________________________________ % by weight ______________________________________ SiO.sub.2 36-40 Al.sub.2 O.sub.3 0-4 B.sub.2 O.sub.3 12-16 Na.sub.2 O 7-9 K.sub.2 O 7-9 ZrO.sub.2 5-10 CaO 4-6 BaO 4-6 P.sub.2 O.sub.5 0-1 CoO 1 NiO 2 MnO 0-2 CuO 0-2 F 0.1.

Abstract: An enamel frit for producing an acid-resistant enamelled steel in a single coating comprising at least about 40% of silicon atoms, 50% of silicon atoms and boron atoms, where the proportion of the boron atoms should not fall below 6.5%, 63% of silicon atoms, boron atoms and sodium atoms, where the proportion of the sodium atoms should not fall below 7.5%, each relative to the overall total of the non-oxygen atoms in the frit, the proportion of the remaining non-oxygen atoms being less than about 37%, and 1.0 to 1.2% of cobalt atoms. In addition, there are (1) x fluorine atoms with 1%.ltoreq.x.ltoreq.11% and at least y lithium atoms and at most 2y lithium atoms with y=(15/x)+5 being present, the proportion of lithium atoms being from about 6.3% to 20% relative to the overall total of the non-oxygen atoms in the frit, or (2) y lithium atoms with 6.3%<y.ltoreq.

Abstract: Fluorine-free titanium white enamel frits for enamelling steel consisting essentially of:35 to 45 parts by weight of the sum of SiO.sub.2 and ZrO.sub.2,18 to 22 parts by weight of TiO.sub.2,18 to 22 parts by weight of the sum of B.sub.2 O.sub.3 and Al.sub.2 O.sub.3,15 to 18 parts by weight of alkali metal oxides,2.5 to 4.5 parts by weight of P.sub.2 O.sub.5, and0.8 to 1.4 parts by weight alkaline earth metal oxides;with the proviso that the ratio of atomic numbers is as follows:(A+2B) to C is 0.9.+-.0.05,(lithium+0.5 magnesium) to phosphorous is 1.+-.0.1, and sodium to potassium is 1.2 to 2.6,wherein A is the sum of monovalent atoms, B is the sum of divalent atoms and C is the sum of trivalent atoms.

Abstract: A high-temperature heating element useful as the heating means in baking ovens, washing machines, water heaters, toasters and dishwashers comprises an enamelled metal substrate and an overlying multilayer system consisting of an inner layer of an insulating glass, metallic conductor lines and an outer layer of a surface glass, wherein said multi-layer system is joined to the enamelled metal substrate by an intermediate layer.

Abstract: An enamel frit which provides improved bonding at stoving temperatures below 800.degree. C. after the frit has been stoved on unalloyed steel which is capable of being enamelled, the frit containing 1 to 6% by weight, based on the total quantity of the frit, of bonding oxides and the other constituents so chosen that the following equation is fulfilled: ##EQU1## in which the deviation from the ratio 1:1:1 is at most .+-.8% for each of the monovalent atoms, divalent atoms and pentavalent atoms.The enamel frits according to the invention being useful for electrostatic powder application.

Abstract: A panel heating element comprising (a) a metal substrate, (b) an aluminum boron-silicate insulating glass which forms a coating on the metal substrate, (c) one or more metallic resistance tracks applied to the substrate and (d) a mixture of a zirconium phosphate glass and a boron-titanium enamel which is applied as a layer over the metallic resistance tracks.

Abstract: The present invention relates to metal substrates which are coated with electrically insulating layers whose electrical resistance has a low temperature dependence, the insulating layer on said metal substrates consisting essentially of a melted-on material containing 43-47% by weight of B.sub.2 O.sub.3, 29-33% by weight of CaO, 10-15% by weight of SiO.sub.2, 7-10% by weight of Al.sub.2 O.sub.3 and 1-2% by weight of MgO.

Abstract: In the electrostatic spraying on metal substrates of mixtures of different inorganic powders which differ in density, particle size and electrical resistance, the improvement which comprises first forming uniform agglomerates as the different powders, and then spraying the uniform agglomerates. This prevents color variation due to separation of different powders.