DE10009185A1 - Production of a relief decoration on a surface of a substrate comprises applying relief-forming moldings made from a powder material containing a glass frit onto the surface and fixing to the surface by ceramic baking - Google Patents

Abstract

Production of a relief decoration on a surface of a substrate comprises applying relief-forming moldings onto the surface and fixing to the surface by ceramic baking at a temperature above the softening temperature of the glass frit contained in the molding. The moldings used are produced by shaping a powder material containing a glass frit. Preferred Features: The moldings are produced by using a shaping aid which can dissolve or swell in water. The shaping aid is produced from natural and chemically modified mono-, oligo- and polysaccharides, and synthetic organic polymers.

Description

The invention relates to a method for producing a Relief decorations on a fireproof substrate, in particular glazed or unglazed ceramics, porcelain, glass and Enamel, the relief height preferably greater than 0.5 mm is and the shape can be designed differently. On another subject relates to those obtainable according to the process Decors.

The decoration of ceramic surfaces, such as tiles, Crockery made of porcelain, bone china and earthenware, and glass, So far, this has been done with thin layers of paint and glaze. Color layers rarely exceed 20 µm in thickness, glazes are usually only 100 to 200 µm thick. For the production Relief-like decorations were tried, thicker colors and Apply glaze layers. An example is the Reference is made to the method according to DE 198 51 206, one or multicolored decor picture before glazing with a hydrophobic organic material is printed and itself thereby forming a relief structure. Relief-like decors with a greater relief depth can be produced by the Relief already during the manufacture of the substrate, for example by means of an appropriately shaped press or Casting mold is produced. After glazing is then at With conventional technology, you need the relief with a decorated with a thin layer of paint.

Only with tiles up to 0.5 mm thick flat reliefs could be produced by creating correspondingly thick glaze layers by direct screen printing. However, the attempts to produce the decors as a water-soluble decal were negative. The following difficulties arose:

• - The drying of the extremely thick layers of paint after the Printing takes a lot of time.
• - With conventional printing processes it is almost impossible another print on the thick decorative layers or to apply a film layer.
• - Leaves water or glue trapped under the picture remove yourself insufficiently by streaking.
• - When burning, the high amount of organic Burn out decor tools before the decor material begins to melt.

The relief decorations produced in this way showed many decor defects, like pinholes (pores), shrinkage cracks and unburned, (coked) organic material.

In various third-party studios in Italy ribbon-shaped reliefs created by decorating color pastes using sprinkles on Listelli (narrow strip-shaped tiles) as a straight band or in Wavy lines are applied. The pastes contain as Pasting medium aqueous solutions of starch, cellulose ethers, Polyoxyethylene derivatives or other water-soluble Thickeners. The decors are on the assembly line manufactured and in belt ovens (throughput time approx. 30 min cold - cold) baked. Due to insufficient drying and The combustion of organic auxiliaries is production associated with considerable committee. In the relatively short Dryers upstream of the belt ovens dry the water from the thick layers is insufficient out. The remaining water evaporates in the heating zone of the belt furnace. This delays the burning out of the organic matter. It happens in the high temperature zone  also for tearing the tiles and coking the organic materials.

Another method of creating a relief can also be used for tiles. Simple shapes (triangles, squares or circles) are cut out of clear glass panes or colored glass panes, placed on the glazed tile and baked at 950 to 1050 ° C. With this fire, the edges of the glass pane melt very nicely round. The disadvantage is that for this purpose only normal flat glass panes with a linear coefficient of thermal expansion around 8. 10 ^-6 / K are available. In the case of thick relief layers, however, the thermal expansion coefficients of the substrate and the relief decoration must match very well. Differences greater than 0.24. 10 ^-6 / K lead to such tensions that the decorative layer tears or is blown off.

The object of the invention is a simple method provide what different flammable Substrates can be decorated with a relief decoration, without significant decor errors.

Another task should follow the procedure Relief decorations with a deep relief structure, in particular one with more than 0.2 mm, in particular more than 0.5 mm, can be produced. It should also be ensured be that the relief material reliably on the Material of the substrate can be matched to flake off to avoid.

These and others are solved from the description resulting tasks through a manufacturing process of a relief decoration on a surface of a fire stable Substrate, comprising application of relief-forming Moldings on the surface and fixing them on the surface due to ceramic fire is characterized that one uses moldings, which  have been produced by shaping at least one a powder material containing glass frit, and that one the fire at a temperature above the Softening temperature of at least one in the molding contained glass frit.

The subclaims, the characteristics of which alone or in Combination can be used with each other, focus on preferred embodiments of the Procedure.

The inventive method for the production of Relief decorations are substrates made of fireproof materials, in particular glass, ceramics of all kinds and metal accessible. These substrates are in unglazed or glazed or enameled form can be used, the Glaze or the enamel unbaked or already baked can be. It is essential that the glass flow from the Molding or / and from a glaze or one Enamel on the substrate a bond between the substrate and conveyed to the molding. Examples of substrates are glazed and unglazed tiles, bricks and others ceramic moldings; Porcelain, bone china and earthenware, the glaze opening before the relief decoration the shards or after the application of the Moldings in the desired decor arrangement in the usual way is applied; Glass, enamelled glass as well enamelled metal.

The moldings used for relief decoration can be by means of molding processes known per se from the Powdery containing at least one glass frit Create material. The powder material becomes dry or wet pressed, cast in molds or extruded. At If necessary, the molding is dried. The Shaping stability for handling can be achieved using adhesive generated or increased; alternatively or additionally a green body can be sintered.  

The shape of the moldings is arbitrary; Examples are round, oval, square, star or moon-shaped plates. Three-dimensional finals can also be created by slip casting Manufacture moldings, for example concentric rings or a lettering on a plate-shaped cylinder. When fired, the edges of the moldings round off.

The composition of the powder material and auxiliary substances can vary widely. Selection criteria are below among other things, the type of substrate, the molding thickness and the desired visual impression. Except for one or more Fluxes, these are generally Glass frits, the moldings often contain pigments or Decorative colors and / or others under the firing conditions infusible substances, with which the flowing of the molding during Decorative fire is reduced or prevented. Important and It is particularly advantageous that by selecting the amount and type of at least one acting as a river Glass frit, the coloring decor colors and additives the relief layer with regard to burning behavior and thermal expansion can be adjusted precisely to the ceramics to be decorated can.

According to a preferred embodiment, the Shaped one or more glass frits in one quantity Range from 10 to 100% by weight, preferably 50 to 100% by weight and particularly preferably 70 to 100% by weight. The Glass frits are known to a person skilled in the art, which one Softening temperature in the range of approximately 500 to 1300 ° C have and also a coefficient of expansion in Have area of the substrates to be decorated. By a combination of several glass frits can do that Flow behavior of the moldings can be adjusted. Lead-containing and lead-free are mentioned as examples Glass frits, such as lead silicates, lead borosilicates, bismuth and / or zinc-containing alkali and / or alkaline earth  Borosilicate, alkaline earth aluminum borosilicate, potassium Calcium aluminum borosilicate.

To form the structure, preferred moldings preferably contain substances which are infusible or only sinterable under the firing conditions in an amount in the range from <0 to 90% by weight, in particular <0 to 30% by weight. These substances, which are difficult to infusible or infusible, are not only correspondingly high, ie above the firing temperature, melting glass frits, inorganic pigments or color bodies containing them, these generally consist of at least one pigment and at least one glass frit and ensure good color development during the fire, and also oxidic and silicatic natural or synthetic substances, such as clays, in particular kaolins, alkaline earth silicates, in particular wollastonite, zirconium silicate and oxides and mixed oxides of the elements Mg, Ca, Al, Sn, Ti and Zr, in particular Al ₂ O ₃ , SiO ₂ , SnO ₂ , TiO ₂ and ZrO ₂ .

The moldings can contain a small amount of one Processing and / or shaping aids contain. The content of such agents is in the range of 0 up to about 10% by weight, preferably 0 to 3% by weight and particularly preferably 0.05 to 1% by weight. The amount of organic material (= shaping aid, Adhesive) that must burn during the decorative firing before the flux can melt due to the Shaping process by pressing or slip casting be kept very low. Essentially they exist liquid pasting media from water and small amounts Adhesive to the pressed or cast molded parts after to be able to manipulate drying. Suitable adhesives to produce sufficient strength of the moldings water-soluble or water-swellable fabrics from the range the natural or chemically modified mono-, oligo- and cationized polysaccharides such as glucose, starch  Starch, carboxymethyl cellulose, hydroxyalkylated starches and celluloses; other substances are water-soluble synthetic organic polymers, such as polyalkylene glycol, Polyvinyl alcohol, polyvinyl pyrolidone, poly (meth) acrylic acids and poly (hydroxyalkyl (meth) acrylates).

The moldings can be made online or off-line long in advance to be produced. In the off-line production of The dry season is independent of that Production cycle for the tile or the tableware part. Each after the equipment of the company, the moldings can Pressing, extruding, molding, such as slip casting or Silicone molds. With especially sensitive processes such as when decorating glass or The moldings can even be pre-sintered enamel and thus any problems with drying or burning Avoid mold aids. The moldings can sintered on a bed of kaolin or the like become. Because not only the color particles are involved in this process glue together, but also the molding aids these moldings burn completely suitable for quick fires.

The moldings can be applied to the substrate done mechanically or manually, for example by Placing on a glazed or unglazed substrate, the glaze can be baked or unfired. Alternatively, the moldings can also be made using a Glue layer to be fixed. The one provided with the molding The substrate is then fired in the usual way. The The firing temperature for ceramic substrates is usually in the Range from 750 to 1250 ° C, with glass in the range from 550 up to 700 ° C and with enamel in the range from 700 to 800 ° C. In front or after the fire, an additional glaze and / or a different colored decor on the with the moldings relief-decorated substrate can be applied.  

The method according to the invention overcomes the problem of Pore formation, cracks and flaking off because of substrate and Relief material (= molding) in its properties can be coordinated. It can be very form flat or raised reliefs. The Utilization of the kilns is optimized because of the moldings regardless of the decoration process can. The decors can be designed in many ways and are not limited to a few structures. Already dried or pre-sintered moldings hardly need additional thermal energy and adapt to it Oven cycle on without problems.

example 1 Spherical domes as relief decoration on tiles

A circular recess 7 mm deep and 2 cm in diameter is milled into a steel plate. A mixture of flow and decorative paint is pressed into this recess at 20 bar. A 5% sugar solution is used as a pressing aid, 2 g are added to 100 g of mixture. The powder mixture has the composition: 90% by weight glass flow (= frit) based on an alkaline earth aluminum borosilicate glass with a start of softening of 920 ° C. and ad ₅₀ value of 6 μm and 10% by weight of a high temperature Rapid firing paint based on an alkali-alkaline earth aluminum borosilicate glass and a Co-Al blue colored body.

The tablet formed by pressing was at 80 ° C dried on a glazed Listello (strip-shaped Decorative tile for wall ends) and at 990 ° C branded. After burning it was a shiny, glowing cobalt blue, 4 mm high, hemispherical button of 2 cm Diameter emerged that firmly with the glaze was merged.  

A second tablet of the same type was opened the unfired glaze applied by spraying placed on a wall tile and also at 990 ° C baked together with the glaze. It also came into being a bright cobalt blue, 4 mm high, hemispherical 2 cm diameter button.

Example 2 Star-shaped reliefs on bone china plate

It became a plaster form with an 8-pointed star manufactured. The star was 5 mm deep and 2.5 cm Diameter. From a flux, a yellow one Decor color, kaolin and 0.5% CMC solution was a pourable slip produced: 85% by weight glass flow, colorless, transparent, finely ground (as example 1), 10% by weight High temperature quick fire color, sun yellow (on the basis of 60% by weight of an alkali aluminum Borosilicate glass with a softening start of 810 ° C and 40% by weight of a zirconium praseodymium yellow body) and 5% by weight Kaolin and 30% by weight (based on the Powder mixture) of a 0.5% CMC solution.

The star in the plaster mold was poured out with it. After 10 min. the star could be removed from the plaster mold.

12 stars of this kind were placed on the flag of a bone china plate. After drying were baked them at 1030 ° C. The stars were after Brand 3 mm thick and shiny, the edges were similar to the blue hemispheres mentioned above are very rounded.

Example 3 Annular relief on porcelain

A plate was poured from silicone impression material into which two rings (2 cm in diameter, 3 mm thick, more square  Cross section) were inserted. After curing, the Rings removed and the following mass into the recesses brushed in: the moldings consisted of 95% by weight a Pb-Zn-Al-B silicate glass with a start of softening 750 ° C (finely ground), 2% by weight of a underglaze color, chrome green, 3% by weight kaolin and 1% by weight sugar (used as a 20% solution).

After drying, the moldings were shaped and dried. They were on the edge of a porcelain plate placed and baked at 900 ° C. It originated on the A relief decor with 1.5 mm thick, chrome-green plates Wrestling.

Example 4 Raised lettering on packaging glass

A plate was poured from silicone impression material into which two letters made of 3 mm thick sheet metal were inserted. After curing, the letters were taken out and the following mass is spread into the depressions. The Moldings consisted of 99.95% by weight of crystal ice, blue (= Pb-B-silicate with 1 wt .-% CoO with a grain size of 80 to 200 µm), 0.05% by weight CMC (used as a 2% solution).

After drying, the letters were carefully removed the silicone mold lifted out and on the flat surface placed in a perfume bottle. After firing at 560 ° C was a transparent, 2 mm thick lettering on the Perfume bottle.

The same mass was used as a ribbon with a garnish syringe extruded with stripes. After targeted drying these strips are placed on flat glass. After this Burning was a window transparency with stripe pattern.

Claims (9)

1. A method for producing a relief decoration on a surface of a fireproof substrate, comprising applying relief-forming moldings to the surface and fixing them to the surface by ceramic firing, characterized in that moldings which have been produced by shaping at least one glass frit are used containing powder material, and that one carries out the fire at a temperature above the softening temperature of at least one glass frit contained in the molding. 2. The method according to claim 1, characterized, that the moldings to be used essentially consist of one or more glass frits in an amount of 10 up to 100 wt .-%, one or more at the temperature of the brand infusible substances in an amount of 0 up to 90% by weight and one or more processing and / or molding aids in an amount of 0 up to 10 wt .-% exist. 3. The method according to claim 2, characterized, that the moldings essentially from 70 to 100 wt .-% Glass frit (s), 0 to 30 wt .-% of one or several infusible substances and 0 to 3% by weight of one or more shaping and / or Processing aids exist. 4. The method according to any one of claims 1 to 3, characterized, that the infusible substances are selected from the Series of inorganic pigments and those containing them Color bodies, clays, especially kaolins,  Alkaline earth silicates, especially wollastonite, Zirconium silicate and oxides and mixed oxides of the elements Mg, Ca, Al, Si, Sn, Ti and Zr. 5. The method according to any one of claims 1 to 4, characterized, that one uses moldings which use at least one dissolved or swollen in water Shaping aid from the range of natural and chemically modified mono-, oligo- and Polysaccharides and synthetic organic polymers were manufactured. 6. The method according to any one of claims 1 to 5, characterized, that the moldings can be pressed, cast or Extrude the powder material in the presence or Absence of a shaping aid and / or Produces water and dries the moldings if necessary and / or sinters. 7. The method according to any one of claims 1 to 6, characterized, that the substrate to be decorated is selected from the range of glazed and unglazed tiles, Bricks or other shaped bodies, glazed and unglazed porcelain, bone china and earthenware as well Glass and enamelled glass and metal. 8. The method according to any one of claims 1 to 7, characterized, that one is provided with at least one molding Substrate for fixing the molding on the Substrate for a ceramic substrate at 750 to 1250 ° C, with a glass substrate at 550 to 700 ° C and with an enamelled substrate at 700 to 800 ° C burns.   9. Relief decor on a surface of a fireproof Substrate, obtainable by the process according to a of claims 1 to 8.