DE1058919B - Process for the production of fire-resistant and non-toxic, yellow and similar colored bodies for ceramic and enamelling purposes - Google Patents

Description

Procedure for. Produce. more fire-resistant and non-toxic, more yellow and similar color bodies for ceramic and enamelling purposes It is a process for the production of fire-resistant and non-toxic, yellow and similar colored bodies known for ceramic and enamelling purposes, which is characterized by that glow-resistant, white oxides suitable as opacifiers, such as tin dioxide, zirconium dioxide or mixtures of these, together with preferably small amounts of oxides Vanadium and / or molybdenum or of such compounds of these elements, which able to transform into oxides during treatment or heating, be annealed.

If you use the color carrier, suitable as an opacifier, incandescent, white oxides - before glowing, small amounts of one or more other white oxides, e.g. B. silicon dioxide, titanium dioxide or aluminum oxide, admixed, you can not only increase the fire resistance, but also the Affect hue.

A bright green-yellow color body can be seen in the implementation the known process using the tin-vanadium system with the addition of alumina hydrate come, while the zirconium-vanadium system with the addition of alumina or silica gives an orange-yellow solid. Obtains a weak corn yellow hue by adding titanium compounds.

This known method makes it possible for the first time, above 1060 ° C To produce glazes of the same color, ivory to yellow, in an oxidizing atmosphere.

There has been no lack of attempts which are characteristic of these compounds to nuance greenish-yellow or corn-yellow color. So will be among others yellow shades with a reddish brown tinge, so-called "chamois colors" desired. Mixtures with the brown ceramic pigments of the iron-chromium zinc-tin with tin system Zircon-vanadium stains result in unstable stains. The brown ceramic color body, which is added to the fire-resistant yellow in small amounts, works more or less in solution; a piebald, brownish yellow is obtained. In addition, there are temperature differences of 20 ° C in an area above 1060 ° C so considerable color fluctuations that mixing with this is not possible.

Attempts have also been made in the tin-vanadium system or tin-vanadium-titanium or zircon-vanadium or zircon-vanadium-titanium or in the corresponding Mixtures of iron-chromium-manganese-cerium-nickel compounds to be incorporated in order to create a stable, emphasizes brownish-reddish yellow. The experiments showed, however, that in one Glaze firing temperature above 1060 ° C unstable color bodies are obtained.

From the glass industry it is known that by adding metals the platinum group or salts of these metals in simple glasses effective color effects can cause. Applying concentrations between 0.0005 and 4 ° / p gives Palladium a yellow-brown, rhodium an apricot to orange-yellow and ruthenium a red to reddish brown color. The colors are extraordinary in a thin layer of glass weak. If you melt the mentioned metals or salts in glazes in a concentration, of 0.4 ° / d, a completely inadequate coloration is obtained; For economic For reasons, a coloring of the glazes in this way is not acceptable, because the for sufficient coloring required concentration of platinum metal or platinum metal salt would be too high. The high cost of the larger amounts of platinum metal or Platinum metal salts are the transfer of the process known in the glass industry inhibiting the process of producing yellow and similar ceramic stains opposite.

A way has now been found which, surprisingly, can be used with very small additions of platinum metal or platinum metal salts are sufficient Preserves color intensity. The new procedure builds on the old one in which the systems Tin Vanadium and Zircon Vanadium are in the foreground. The new method of manufacture fire-resistant and non-toxic, yellow and similar color bodies for ceramic and enamelling purposes, with incandescent white ones suitable as opacifiers Oxides such as tin oxide, zirconium dioxide or mixtures of these, together with small amounts of oxides of vanadium and / or molybdenum or of such compounds of these This means that elements that change into oxides when heated are annealed characterized in that the mixture before the annealing only small amounts, preferably less than 10 / "one Platinum metal or a platinum metal salt or a mixture of these can be added.

As already mentioned, the addition of platinum metal or is limited Platinum metal salts not on just one substance each; mixtures can of course also be used various kinds are added. It is also not necessary, only tin oxide or to use only zirconia; : s is quite possible next to tin- at the same time Zirconium) or other equivalent metal compounds. There were the following Experiments carried out: A. Zirconium-Vanadin system + 1 to 3% platinum metal chloride; 3 ° / o color bodies for the glaze If one looks at the well-known refractory colors in the system Zirconium vanadium adds 1 to 3 ° / ö of the compounds listed below, above 1200 ° C, preferably at 1350 ° C, calcined and -3> ° / o of the color oil formed in this way a glaze, e.g. B. a zirconium-cloudy glaze,: adds and then fires at 1100 ° C, the following is found for the) two process steps: 1. Rhodium chloride results -a- deep yellow color powder; in the. Glaze is produced a weak - yellow color.

2. Platinum chloride gives a brownish yellow; gets in the glaze one a faint yellow.

3. Results in ruthenium chloride. an almost pure canary yellow; -the glaze however, it is weak in color.

4. Palladium chloride produces a gray color pigment; the glaze shows a dirty gray color. By adding 1 to 3 g of the compounds mentioned, u the original batch amounts, z. B. 100 g of zirconium) oxide and 2 g of ammonium vanadium, therefore there is an imperceptible intensification of the color in the acids. - -B. System tin vanadium -E- 0.5 l) /, platinum metal chloride; 3% additive to the glaze If a mixture of 100 parts of tin oxide with 3 parts of ammonium granadate is used as the base for the color, 0.5 part of the compounds listed below is added to 100 parts of oxide and the mixture is calcined above L200 ° C, then, surprisingly, the following color shades result: 1. Rhodium chloride with 3 % addition of color body to a commercially available zirconium glaze: Intense yellow-brown. 2. Ruthenium chloride with 3 % color body addition to the glaze: yellow-green.

3. Palladium chloride in a glaze with 3% color body addition: green-gray.

C. Addition of titanium dioxide. B. the rhodium-containing :; be elb color solids. Because of its relatively low prime costs it does not, however, find any use.- Further experiments have now: that with a minimum of rhodium chloride in the tin-vanadium system, an intensive reddish - :) can produce a rough yellow if you add fitandioxyd at the same time. As a result, the content of rhodium chloride can be reduced without affecting the hue ) of which the intensity can be fundamentally changed.

These experiments have shown that primarily the 3hloride of Rhodium, ruthenium and palladium come into question. The most favorable limits for that Amounts of the additive are as follows: 0.05 to 0.5 parts by weight of platinum metal salt, preferably Chloride, for every 100 parts by weight of the incandescent, white, as opacifying agent suitable oxide. _. One can; as with the older method, also here before the Additionally glow other white oxides, e.g. B. silicon dioxide, titanium dioxide and / or Add aluminum oxide. The beneficial effect of the addition of titanium dioxide - at the Implementation of the new procedure has already been mentioned. These oxides become most preferably in an amount of 0.1 to 5 parts by weight per 100 parts by weight of the Oxide suitable as an opacifier was added.

The addition of the colored substance to the glaze can be 1 to 3 parts by weight per 100 parts of frit. For use in sanitary ceramics, 1 to 6 parts by weight of color bodies are added to the known raw glazes; This glaze, when fired above 1240 ° C, gives a stable reddish-brown yellow. example The following is used for the manufacture of the color body Mixture I made Parts by weight Tin oxide ............................. 100.0 Ammonium vanadate. . . . . . . . . . . . . . . . ... . 3.0 Titanium oxide ............................ 1.5 Rhodium chloride ....................... 0.25 104.75 The mixture I is wet-ground, dried, comminuted and calcined at 1350 ° C. for a holding time of one hour. The color body is crushed, freed from any salt residues that may be present with water and dried. The color body produced in this way can now be used.

A zirconium-cloudy frit with the following molar composition 0.33 Na20 2.42 Si 02 0.24 CaO 0.30 B203 0.22 Zn 0 O35 Al 203 0.13 K20 0.15 Zr02 0.04 Pb O 0.04 F2 0.04 B.0 is colored to a stable chamois glaze Mixture II Parts by weight Frit .................................. 100.0 Color bodies after mixture I ....... 1.5 to 3.0 Kaolin ................................. 8.0 Mixture II is ground so finely that no residue remains on the 6400-mesh sieve; it is used to glaze plates or other ceramic products and bake them between 1040 and 1140 ° C.

Claims (3)

PATENT CLAIM_ 1. Process for the production of fire-resistant and non-toxic, yellow and similar colored bodies for ceramic and enamel technical purposes, whereby incandescent white oxides suitable as opacifiers, such as tin dioxide, zirconium dioxide or mixtures thereof, together with small amounts of oxides of vanadium and / or molybdenum or of such compounds of these elements which are converted into oxides on heating, characterized in that only small amounts, preferably less than 10 / "of a platinum metal or a platinum metal salt or mixtures thereof are added to the mixture before the annealing. 2. The method according to claim 1, characterized in that to j e 100 parts by weight of the opacifier suitable oxide of j e 0.05 to 0.5 parts by weight of platinum metal salt, preferably chloride, are added. 3. The method according to claim 1 and 2, characterized in that in addition before annealing other white oxides, e.g. B. silicon dioxide, titanium dioxide and [or aluminum oxide, in small amount, preferably 0.1 to 5 parts by weight per 100 parts by weight of the as Opacifying agents of a suitable oxide can be added.