DE10359884A1 - Substrates with a transparent, reflective metal oxide partial coating, their preparation and application - Google Patents

Abstract

The present invention relates to a process for producing a substrate, in particular a metal, ceramic, plastic or glass substrate, with a partially transparent and / or reflective coating of titanium dioxide with easy-to-clean properties. Furthermore, the present invention relates to a paste for producing a substrate, in particular a metal, ceramic, plastic or glass substrate, with a partially transparent and / or reflective coating of titanium dioxide with easy-to-clean properties, a substrate obtainable according to the inventive method and the use of the substrate.

Description

Territory of invention

The The present invention relates to a process for producing a Substrate, in particular a metal, ceramic, plastic or Glass substrate, with a partially transparent and / or reflective Titanium dioxide coating with easy-to-clean properties. Of Furthermore, the present invention relates to a paste for the production a substrate, in particular a metal, ceramic, plastic or glass substrate, with a partially transparent and / or reflective Titanium dioxide coating with easy-to-clean properties, a substrate, available according to the inventive method as well as the use of the substrate.

background the invention

In The coating technology is thin oxidic coatings for a long time in the form of metal chandeliers known mainly for the decoration of porcelain and earthenware, but also be used by glass. These coatings last without Add adhesives directly to the substrate.

Of the Application is carried out by brush, spraying or screen printing, whereby colored or iridescent layers are obtained.

It is also known thin Oxide layers, in particular specially reflective oxide layers, by Steaming methods such as e.g. CVD method or by sol / gel method apply.

That's how it describes DE 197 08 808 A1 a special vapor deposition method for applying transparent protective coatings to articles carried out on undried air at atmospheric pressure and at a temperature lower than 500 ° C in an oven, mixing a second gas stream comprising a compound of silicon and a monocarboxylic acid to the undried air at a vapor pressure of greater than 2 Torr and which is generated by evaporating a liquid containing the compound of silicon and a monocarboxylic acid in non-crystalline form, using a liquid which does not react with the compound of silicon and a monocarboxylic acid still participates in the deposition of the transparent protective layer.

The DE 100 65 647 A1 describes a vapor deposition material for the production of high refractive optical layers of titanium oxide, titanium and lanthanum oxide in vacuo, wherein the evaporation materials on suitable substrates homogeneous thin layers of uniform thickness are produced which are resistant to adhesion and particularly resistant to mechanical and chemical influences.

Sol / gel process are used to form nanoscale metal oxide particles, in particular also titania, on metal, ceramic and glass substrates as dense To deposit a layer. In this case, the nanoscale metal oxide particle already exists in the suspension.

The DE 199 46 712 A1 describes a process for printing on substrates, wherein a printing paste is used, comprising the obtained by the sol / gel process matrix-forming precondensate based on polyorganosiloxanes and one or more coloring luminescent conductive and / or catalytically active fillers applied to the substrate and be compacted by a heat treatment, wherein the compaction is carried out at a temperature which is lower than the glass transition temperature of the forming matrix.

The DE 195 25 658 C1 describes a burnable printing paste for printing on glass surfaces, which consists of a low-melting glass component, an inorganic color pigment component and an organic binder component for adjusting the flow properties required for the printing process and for achieving sufficient strength after drying. In this case, the inorganic color pigments are coated with a 0.5 to 5 .mu.m thick layer of a glass or a thermally solidified gel corresponding to a glass composition, wherein the coating of the color pigments is carried out by the sol / gel process.

The DE 41 05 235 A1 relates to a coated system comprising a substrate of metal, ceramic or quartz glass provided with an enamel or glaze layer, which has a highly aesthetic and chemically very stable surface layer of high aesthetic appeal, which is obtainable by means of the specular and optionally iridescent and / or body color Application of aqueous metal oxide sols and a subsequent drying and cooling process.

The patent DE 696 11 618 T2 describes the wet-chemical coating of substrates with partially crystallized titanium dioxide and mixed anatase, whereby photocatalytic properties are achieved. The titanium oxides may contain a variety of other metal oxides.

The patent DE 696 14 358 T2 describes the deposition of a titanium dioxide film with photocatalyzed tischer effect and a substrate with this film. In this case, it is assumed that a titanium fluoride-containing solution from which titanium dioxide is deposited by means of a boric acid additive and this is then calcined.

The DE 44 07 366 A1 describes a method of applying an enamel-like layer to a glass surface using a printing ink containing inorganic binders, the inorganic binders comprising an aqueous suspension of nanometer-sized metal oxides which polycondensate under the influence of temperature.

Of the However, the aforementioned prior art has the disadvantage that the application of a decorative partial coating on surfaces of Substrates difficult or impossible is.

Also There is an increasing demand for the production of self-cleaning Surfaces. To achieve a good self-cleaning effect of a surface must this in addition to a good hydrophobicity and a microrough surface structure exhibit. Both features are in nature, for example in the lotus leaf, realized; has the surface formed of a hydrophobic material pyramidal Elevations on which a few microns from each other are removed. Water drops come essentially only with these Tips in touch, so that the contact surface tiny, which has a very low adhesion. These relationships as well teach the basic applicability of the "lotus effect" to technical surfaces A.A. Abramzon, Khimia i Zhizu (1982), No. 11, 38-40.

in the State of the art are numerous methods for producing self-cleaning surfaces known.

there is generally the substrate surface with silane, siloxane or Coated silicone compounds.

For example, that teaches EP 0 909 747 A1 a method for producing a self-cleaning property of surfaces, wherein a dispersion of powder particles of an inert material in a siloxane solution is applied to the surface and then cured. However, in this case the structure-forming particles are not fixed to the surface of the substrate so as to be resistant to abrasion.

Out EP Patent 0 772 514 are self-cleaning surfaces of objects with an artificial one surface structure from surveys and wells known, which may be after structuring a hydrophobing, for example a silanization, followed.

Indeed These coatings are thermal and chemical not very stable and have only a low abrasion resistance.

Summary the invention

The The present invention provides a new and improved method for producing a substrate, in particular a metal, ceramic, plastic or glass substrate, with a partially transparent and / or reflective coating Titanium dioxide with easy-to-clean properties ready, with a paste, comprising a printable titanium solution, the titanium predominantly is complex bound, is applied to the substrate and through a heat treatment is compressed. The application of the paste can by means of screen printing, pad printing or offset printing is applied to the substrate. Further notes the present invention provides a novel paste for making a Substrate, in particular a metal, ceramic, plastic or Glass substrate with a partially transparent and / or reflective coating made of titanium dioxide with easy-to-clean properties, taking the paste a printable titanium solution wherein the titanium is present predominantly complexed. The printable titanium solution comprises titanium nitrates, chlorides, acetates, isopropanolates, acetylacetonates, salicylates or polyacrylates or mixtures thereof.

Further the paste comprises solvent, Metal oxides, precious metals and thickeners. Another item The invention is a substrate obtainable by the process according to the invention as well as the use of the substrate according to the invention in construction and in the field of architecture, in the transport sector, at urban Facilities and for Decorative purposes in the glass and ceramic industry.

detailed Description of the invention

The The object of the present invention is to provide a method for disposal to put, with a decorative partial coating on a substrate easily possible is. This task is solved by claim 1.

It For example, there is provided a process for producing a substrate, in particular a metal, ceramic, plastic or glass substrate, with a partially transparent and / or reflective coating of titanium dioxide with easy-to-clean properties, wherein a paste comprising a printable titanium solution, wherein the titanium is predominantly complexed, on the substrate is applied and compacted by a heat treatment.

The Paste can be screen-printed, pad-printed or offset-printed be applied to the substrate.

It However, all other methods are also suitable in which pastes can be used, which are known in the art from the prior art.

To the application of the paste to the substrate is at a temperature from 50 ° C up to 180 ° C dried. Thereafter, it is calcined at a temperature of 200 ° C to 1000 ° C. It is preferred if calcined in a temperature range of 400 ° C to 700 ° C. becomes.

A Another object of the invention is the provision of a paste, with the application of decorative partial coatings on one Substrate easily possible is. The task is solved by a paste according to claim 5th

It is a paste for producing a substrate, in particular a Metal-ceramic, plastic or glass substrate with a partially transparent and / or reflective Titanium dioxide coating provided with easy-to-clean properties, wherein the paste comprises a printable titanium solution, wherein the titanium predominantly complex bound exists.

The printable titanium solution includes titanium nitrates, chlorides, acetates, isopropanolates, acetylacetonates, salicylates or polyacrylates or mixtures thereof.

Further can the paste solvent, Metal oxides, precious metals and thickeners.

When solvent preferably alcohols such as ethanol, n-propanol, isopropanol, Butanols and glycols such as e.g. the di-, tri-, tetra-, penta- or Hexamers of monoglycols, polypropylene glycols such as dipropylene glycol, Tripropylene glycol and tetrapropylene glycol and their derivatives in Consideration.

All particularly preferred is the use of tripropylene glycol methyl ether.

Of course you can too two or more of these solvents or a mixture thereof.

Furthermore, metal oxides or even noble metals can be added to the paste for the purpose of coloring or IR reflection. The metal oxides are selected from the group consisting of CuO, Cr ₂ O ₃ , CoO, Fe ₂ O ₃ , MnO, Al ₂ O ₃ , ZrO ₂ , CeO ₂ , Y ₂ O ₃ .

When Precious metals are precious metals such as Ag, Au, Pt and Pd into consideration.

Further the paste has as thickener cellulose derivatives such as methyl or ethyl cellulose or Polyacrlsäuren on. The thickeners serve to adjust the paste required viscosity, so that it can be used for printing.

Of further, the paste can be extra Contain additives for Pastes in use are.

The Preparation of the paste according to the invention Fulfills after the for the person skilled in known methods, wherein the components combined and be pasted.

Of the Core of the invention is that titanium solutions in organic water-compatible solvents can be used, wherein the titanium is bound mainly complex and the solubility through macromolecular compounds is set.

Farther It is also an object of the invention to provide a substrate with a decorative To provide partial coating. This object is achieved by the patent claim 14 solved.

The inventive substrate with the thus applied coating is characterized by an im Compared to silicate glasses, especially soda lime glasses lower Surface tension, synonymous with increased Contact angles of polar liquids like water. The film that forms when wetting the surface with water comes on lowest tendency without residue from. The substrates according to the invention have coatings, which in relation to the above mentioned in the prior art Coatings by a higher Abrasion resistance and chemical, thermal and UV radiation are much more stable.

The emergence of easy-to-clean properties can be attributed to the formation of a radiopaque dense TiO ₂ coating with correspondingly lower surface energy than soda-lime glasses. As a result, an initially forming water film withdraws without residue.

If it desired is, can Of course also several coatings with different pictorial representations next to each other on the surface a substrate are applied.

The substrates according to the invention can are used in construction and architectural, transportation, urban and decorative purposes in the glass and ceramics industries, of course, the use is not limited to the above-mentioned uses.

imaginable is the use as architectural glasses, for example in shower cubicles, in particular limescale due to easy-to-clean properties are easy to remove.

One Another field of application can be found at Spiegel for the sanitary sector and at Spiegel outdoors.

in the Transporting the coating, for example, on rearview mirror, Rear and side windows and be applied to roof glazing.

Also can the substrates according to the invention for decorative purposes in the glass and Ceramics industry can be used. For example, drinking glasses are featured Such a coating by a good dishwasher strength.

The Invention will be described below by the examples which do not limit the invention.

example 1

4.85 g of 65% HNO ₃ are mixed in 40 g of Dowanol TPM. 4.358 g of titanium tetraisopropoxide are added with stirring. The result is a clear yellow solution. 20 g of a solution of 8.5% Glucel L in Dowanol TPM are added to this solution. The paste is printed on 4 mm thick flat glass by means of a 140TX screen fabric, dried at 120 ° C. and then fired at 660 ° C. for 4 minutes in an electric furnace. The disc is cooled with compressed air. The result is a semi-transparent reflective surface, which is barely visible in transmitted light.

Example 2

7,216 g polyacrylic acid (MM = 2000) are dissolved in 25 g of Dowanol TPM hot. 4.358 g of titanium tetraisopropoxide are dissolved in 20 ml Dowanol TPM and the polyacrylic acid solution. The result is an orange clear solution. To be this solution 15 g of a solution of 8.5% Glucel L in Dowanol TPM. The paste is made by means of of a screen fabric printed on 4 mm thick flat glass for 100 s, dried at 120 ° C and then at 660 ° C 4 Burned in an electric oven for a few minutes. The disc is compressed air cooled. The result is a semi-transparent specular iridescent surface, which hardly visible in transmitted light. Applied with a sieve 140TX the layer is colorless.

Example 3

2.52 g ZrOCO ₃ × nH ₂ O (39.7% ZrO ₂ ) are dissolved in 1.45 g HNO ₃ , 65%, and mixed with 15 g Dowanol TPM. 4.34 g of polyacrylic acid (MM = 2000) are dissolved hot in 30 g of Dowanol TPM. Both solutions are mixed together. It creates a clear solution. For thickening, 10 g of a solution of 8.5% Glucel L in Dowanol TPM are added. The resulting mixture is mixed with the solution of Example 2 in the ratio 1: 1. The paste is printed by means of a mesh fabric 100s on 4 mm thick flat glass, dried at 120 ° C and then fired at 660 ° C for 4 minutes in an electric furnace. The disc is cooled with compressed air. The result is a partially transparent colorless reflective surface, which is barely visible in transmitted light.

Example 4

0.251 g of copper (II) acetate Cu (CH ₃ COO) ₂ × H ₂ O are dissolved in 0.275 g of HNO ₃ , 65%, and 0.1 g of water and mixed into 8 g of a solution according to Example 1. The paste is printed by means of a screen fabric for 100 s on 4 mm thick flat glass, dried at 120 ° C and then fired at 660 ° C for 4 minutes in an electric furnace. The disc is cooled with compressed air. The result is a semi-transparent yellowish-reflective surface, which appears tinted brown in transmitted light.

The 1 shows a glass substrate according to the invention.

Claims (13)

Method for producing a substrate, in particular a metal, ceramic, plastic or glass substrate, with a partially transparent and / or reflective titanium dioxide coating with easy-to-clean properties, with a paste comprising one printable titanium solution, wherein the titanium is predominantly complexed, on the substrate is applied and compacted by a heat treatment. Method according to claim 1, characterized in that the paste by means of screen printing, pad printing or offset printing is applied to the substrate. Process according to claims 1 and 2, characterized in that at a temperature of 50 ° C to 180 ° C dried is calcined at a temperature of 200 ° C to 1000 ° C. Method according to claim 3, characterized that at a temperature of 400 ° C up to 700 ° C is calcined. Paste for producing a substrate, in particular a metal, ceramic, plastic or glass substrate with a partially transparent and / or reflective titanium dioxide coating with easy-to-clean properties, the paste being a printable titanium solution wherein the titanium is present predominantly complexed. Paste according to claim 5, characterized in that the printable titanium solution Titanium nitrates, chlorides, acetates, isopropanolates, acetylacetonates, salicylates or polyacrylates or mixtures thereof. Paste according to claims 5 and 6, characterized the paste also contains solvents, metal oxides, Includes precious metals and thickening agents. Paste according to claim 7, characterized in that the solvents selected are from alcohols, glycols, polypropylene glycols and derivatives thereof. A paste according to claim 7, characterized in that the metal oxides are selected from the group consisting of CuO, Cr ₂ O ₃ , CoO, Fe ₂ O ₃ , MnO, Al ₂ O ₃ , ZrO ₂ , CeO ₂ , Y ₂ O ₃ . Paste according to claim 7, characterized in that the paste includes precious metals such as Ag, Au, Pt and Pd. Paste according to claim 7, characterized in that the paste comprises, as thickener, cellulose derivatives or polyacrylic acids. Substrate, available according to the method according to claim 1. Use of the substrate according to claim 13 in construction and architecture, in the transport sector, at urban Facilities and for Decorative purposes in the glass and ceramic industry.