DE1106898B - Yellow pigments - Google Patents

Description

Yellow Pigments It is known to use fire-resistant yellow pigments ceramic and enamel applications by using zirconium dioxide, Tin dioxide or mixtures of both oxides with the addition of oxides of vanadium and / or Molybdenum or such compounds of these elements, which when heated into oxides able to pass over, glows.

Attempts have also been made to determine the hue and purity of the the aforementioned pigments by adding small amounts of metals of the platinum group or their Salts or small amounts of gallium oxide and / or indium oxide and / or yttrium oxide to improve. Apart from the fact that these additives are expensive, they hold up the improvements only within narrow limits.

This invention relates to extremely pure, bright yellow, temperature-resistant yellow pigments based on zirconium dioxide, tin dioxide or Mixtures of both oxides and vanadium oxide, which contain bismuth (III) oxide exhibit..

The hue and color saturation, as well as the brightness of these yellow ones Pigments depend on the amounts of vanadium oxide they contain as well as on the molecular ratios of vanadium oxide to bismuth (III) oxide. These amounts or proportions can vary within wide limits.

Pigments with a content of about 0.5 to about 20 % and in particular of about 2 to about 10% vanadium oxide and a molecular ratio of about 1.1: 1.0 and about 1.0: 1.1 of the vanadium oxide to bismuth (III) oxide are characterized by particularly good color properties.

The new yellow pigments are made so that a mixture of Components is converted into the color body by annealing at elevated temperature. In this case, heat-unstable compounds can also be used instead of the oxidic components the metals on which the components are based are used, which upon heating pass into the desired oxidic constituents of the yellow pigments. So z. B. instead of zirconium dioxide or tin dioxide that when heated into the dioxide passing oxydhydrate or nitrate can be used. Instead of vanadium oxide can use the ammonium salt of metavanadic acid instead of wisrmut (III) oxide whose nitrate is used. You can also use aqueous or other solutions all substances involved through alkalis (e.g. NH3) as hydroxides or hydrated oxides precipitated or evaporated the salt solutions or brine or gels of the substances involved can be used. If necessary, the mixtures can be used to facilitate the implementation small amounts of a flux, e.g. B. L'F or NaF, can be added.

The products thus obtained can, for. B. in the ceramic and enamel technical field use. Example 1 5.000g Zr02 are mixed well with 0.542g Bi203 and 0.212g V205 (from NH4V03), heated for 1/2 hour at 700 ° C, after pulverization 1/2 hour at 1000 ° C. A very full, purely bright yellow pigment is obtained.

Example 2 5.000 g of ZrO2 are mixed with 0.271 g of Bi203 and 0.106 g of V205 (from NH4V03) mixed well, 1/2 hour at 700 ° C, after pulverization 1/2 hour heated to 1000 ° C. A full, purely bright yellow pigment is obtained.

Example 3 5.000g ZrO2 (from nitrate) are combined with 0.542g B'203 and 0.212 g V205 (from NH4V03) mixed well, 1/2 hour at 700 ° C, after pulverizing 1/2 Heated to 1000 ° C for an hour. A pure yellow pigment is obtained.

Example 4 4.000g Zr02 and 1.222g Sn02 are mixed well with 0.542g B'201 and 0.212g V20 (from N H4V03), heated for 1/2 hour at 700 ° C, after pulverization for 1/2 hour at 1000 ° C. A pure yellow pigment is obtained.

Example 5 2.000g ZrO2 and 3.666g SnO2 are mixed well with 0.542g Bi.0 , and 0.212g V205 (from NH4V03), heated to 700 ° C for 1/2 hour, after pulverization to 1000 ° C for 1/2 hour. A light yellow pigment is obtained. EXAMPLE 6 5,000 g of SnO2 are mixed well with 1,000 g of B'203 (from nitrate) and 0.390 g of V205 (from NH4V03), heated for ½ hour to 800 ° C., after pulverization, heated to 1000 ° C. for 1/2 hour. A purely bright yellow pigment is obtained.

Claims (1)

PATENT CLAIM: Yellow pigments based on zirconium dioxide, tin dioxide or mixtures of both oxides and vanadium oxide, characterized by a content of bismuth (III) oxide.