DE102009012461A1 - Metallic carrier body such as metal sheet or strip useful as pollutant-reducing component in building construction and civil engineering, comprises patina layer applied on the carrier body, where the patina layer contains metal compounds - Google Patents

Abstract

The metallic carrier body (10) such as a metal sheet or a strip comprises a patina layer (11) applied on the carrier body, where the patina layer contains metal compounds and 95-100% of a surface of the patina layer are made of titanium dioxide (12), which is present in form of particles and present as film. The metallic carrier body consists of metal alloy. The diameter of the particles is smaller than the thickness of the patina layer, where the ratio of the diameter to the thickness is 0.002:0.9. A layer thickness of a layer area adjacent to the carrier body does not exceed 400 nm. The metallic carrier body (10) such as a metal sheet or a strip comprises a patina layer (11) applied on the carrier body, where the patina layer contains metal compounds and 95-100% of a surface of the patina layer are made of titanium dioxide (12), which is present in form of particles and present as film. The metallic carrier body consists of metal alloy. The diameter of the particles is smaller than the thickness of the patina layer, where the ratio of the diameter to the thickness is 0.002:0.9. A layer thickness of a layer area adjacent to the carrier body does not exceed 400 nm. The patina layer and/or the titanium dioxide film are transparent, and contain micro-cracks. The patina layer is tinned. An independent claim is included for a method for producing a metallic carrier body.

Description

The The present invention relates to a copper-containing metallic Carrier body, comprising one on the carrier body arranged layer, wherein the layer is a metal compound and Titanium dioxide contains and wherein 3 to 100% of the surface the layer of titanium dioxide are formed. The invention relates Furthermore, the use of the metallic carrier body as a pollution-reducing component and a method for the production of the metallic carrier body.

It is known in the prior art that TiO ₂ (in particular in the anatase or brookite modification) is photocatalytically active on irradiation with UV light or daylight and can be used for the purification of wastewater and air.

The WO 99/33564 Proposes the use of TiO ₂ for indoor and outdoor air purification, for example, where interior walls of rooms, exterior walls of buildings including windows and roofs, paving slabs and pavements are coated with a thin photocatalytically active layer. By doping TiO ₂ with metal ions, it is possible to achieve a good photocatalytic activity of the TiO _2, in particular also under visible light. An advantage of these applications is that the TiO _2, especially on ceramic or mineral substrates has a very good adhesion and thus has a good resistance to weathering especially when used outdoors on such substrates.

Roof tiles or roof tiles which contain TiO ₂ particles on the surface are already known in the prior art. By means of the TiO ₂ particles, photocatalytic nitrogen oxides NO _{x are converted} into harmless substances such as NO ₃ ^- on the surface of these products by the action of daylight. For example, NO _x is produced during the combustion of oil and gas in heating systems, power plants and vehicles and exacerbates pollution, especially in urban areas.

It is also known in the prior art that organic substances can also be decomposed photocatalytically by TiO ₂ . Examples include the degradation of benzene and aldehydes.

Especially in modern architecture a lot of metal is used nowadays. In particular, but also have many old houses metal roofs, especially copper roofs. In order to reduce the environmental impact of burning fossil fuels in heating systems, power plants and vehicles, it would therefore be advantageous also to prove such building surfaces with catalytically active TiO ₂ , which have no ceramic or mineral carrier body but a metallic carrier body. However, the adhesion of TiO ₂ to metals is difficult to realize, so that, especially outdoors, a TiO ₂ coating with photocatalytically active particles may not have a sufficient lifetime.

Titanium zinc is a prior art Zn alloy for roofing, according to US Pat DIN EN 988 contains up to 0.02% Ti. During production and storage in air, a thin, Zn-rich oxide patina forms on the surface, which may also contain TiO ₂ in small amounts. Because of the low Ti content of the alloy, the TiO ₂ concentration at the surface is also low. Such a titanium zinc is therefore not sufficiently suitable to contribute to a photocatalytic reaction for air purification.

TiO ₂ is also used as a pigment in lacquers and paints, which are also used on metal sheets, for example, in white paints in automotive plates. In this case, the particles are embedded in a matrix of organic binding materials and thus come into contact with the ambient air only to a limited extent or not at all. The contribution to photocatalytic reactions with the ambient air is therefore very limited. An attempt is currently being made to utilize the photocatalytic effect in such paints by developing paint binder systems with TiO ₂ particles, which partially decompose under UV action and thus increase the surface of TiO ₂ particles for photocatalytic reactions with the ambient air. A disadvantage with this system is that the exposed surface of the TiO ₂ particles required for reactions with the ambient air is not present from the beginning, but is available only after the conversion of the paint surface under light or UV radiation with correspondingly large time requirements and still not big enough.

The EP 1835051 A2 describes a self-cleaning surface with catalytically active titanium oxide, wherein the self-cleaning surface consists of a metal matrix, in which the photocatalytically active titanium dioxide is incorporated in the form of particles. The metal matrix is deposited galvanically on a conductive surface and is particularly suitable as a surface coating, for example, for chromed vehicle exterior surfaces. This solved the problem of adhesion of TiO ₂ particles to metal. However, only a small part of the TiO ₂ particles protrude out of the surface, so that the available catalytically active surface for air purification is too small. The part in the metal matrix is not available for catalytic reactions because the Me medium (air) can not penetrate into the metal.

The object of the present invention was therefore to provide a metallic building material which provides sufficient adhesion of TiO ₂ and has a sufficiently large catalytically active surface.

The Task was solved by a metallic carrier body, which consists of a metal alloy containing at least 0.01% by weight Contains copper, comprising one on the carrier body arranged layer, characterized in that the layer as Metal compound copper salt and / or copper oxide and / or copper hydroxide and / or intermetallic phases of tin and copper and / or tin-copper compounds and titanium dioxide and wherein 3 to 100% of the surface the layer of titanium dioxide are formed.

With the surface in the context of this invention is the for a fluid medium, such as air, accessible surface meant.

The corresponding metal of the oxide, hydroxide and / or salt corresponds preferably the metal of the metallic carrier body. The proportion of the metal compound in the layer is preferably 40 to 99 wt .-%, preferably 60 to 99 wt .-% and especially preferably 90 to 99 wt .-%, based on the total weight of the layer.

It it was surprisingly found that the photocatalytic Effect even at very low levels of copper ions or copper atoms in the layer is very pronounced, with the copper ions or copper atoms, especially in patinated copper products but also in tinned copper products are sufficient, if in the Carrier body or the tin layer a certain Minimum amount of copper is included. The lower limit is added 0.01 wt .-% copper seen. Preference is given to higher copper shares of more than 0.05 wt .-%, in particular copper content of more than 0.5 Wt .-%.

In Another preferred embodiment is on The carrier body arranged layer a Patina layer.

In In a particularly preferred embodiment, the patina layer is a copper patina layer. In this case, the metal compound is preferably copper oxide, Copper hydroxide and / or a copper salt or mixtures thereof. at the copper salt may be, for example, copper carbonate, copper sulfate, copper chloride, Copper hydroxide and mixtures thereof, also salts of Uric acid (urates) and salts of other organic and Part of inorganic acids (basic copper compounds).

According to the invention further preferred that the titanium dioxide in the form of particles in the layer is present.

In An embodiment of the invention is preferably the Diameter D of the particles larger than the thickness S of the layer. The ratio D: S is approximately in the range from 1.02 to 1.5, preferably 1.1 to 1.4.

In Another preferred embodiment is the diameter D of the particles smaller than the thickness S of the layer. The relationship D: S is about 0.002 to 0.9, preferably 0.01 to 0.8.

In Still another preferred embodiment is the surface the layer arranged on the carrier body at least 95%, in particular 100% formed by titanium dioxide. The titanium dioxide is preferably in the form of a film on a layer Metal compounds with Cu (I) oxide and / or Cu (II) oxide, whose Layer thickness does not exceed 400 nm.

In the surface accessible to fluid media the proportion of the metal compound is preferably 0.1 to 1.0 wt.%, preferably 0.01 to 0.1 wt.%, more preferably less than 0.01 wt .-%, based on the total weight of the layer.

In Another preferred embodiment is the layer and / or the titanium dioxide film transparent.

In still another preferred embodiment the layer and / or the titanium dioxide film microcracks.

The arranged on the carrier body layer can further, a copper-containing tin coating.

Of the Inventive metallic carrier body is suitable as a pollution-reducing component, in particular as Component in building construction and civil engineering as roofing or as facade cladding.

object The invention is also a method for producing a metallic Carrier body, comprising the production of a layer, containing a copper-containing metal compound and titanium dioxide, on a carrier body.

As a metallic carrier body in the context of this invention is to be understood a metallic carrier body, which is particularly in construction, for example, for roofing or facades fairing is suitable. The metallic carrier body preferably consists of copper or a copper alloy, for example of a CuAl or SnCu alloy. Particularly preferred is also a combination of a carrier body of copper or a copper alloy which is coated with a copper-containing tin alloy. Particularly preferably, the metallic carrier body is a metal sheet or strip. The sheet or strip may, for example, have a thickness of 0.2 to 0.8 mm, preferably 0.25 to 0.75 mm, particularly preferably 0.3 to 0.6 mm in thickness.

The Layer containing the metal compound may be on the one hand by natural weather conditions can form on the metal carrier body, but can also artificial, d. H. factory-generated. For example is known for copper and copper alloys that are in the course of the time forms a patina layer, which is also synthetic a copper sheet or a copper alloy can be produced. In this case, it is located on the carrier Metal compound to a copper compound, in which case complex mixtures arise from copper salts, copper oxides and copper hydroxides. in the In the simplest case, a patina layer can be created by a reaction solution applied to copper or a copper alloy which is capable of a copper oxide layer or a patina to build. Methods for patinating are known in the art, for example the application of solutions containing copper salts and / or Ammonium compounds.

The titanium dioxide is present in the layer arranged on the carrier body, preferably in the form of particles. Crucial for the photocatalytic activity of titanium dioxide is that this can come into contact with the ambient air and thus the conversion of air pollutants can take place. This can be achieved according to the invention in that the diameter D of the particles is greater than the thickness S of the layer. The ratio D: S can be chosen approximately in the range of 1.02 to 1.5. The particle size is preferably 2 nm to 40 μm, more preferably 2 nm to 100 nm. In this case, the thickness of the layer is preferably about 1.96 nm to about 39.2 μm, more preferably about 1.96 nm to about 98 nm The surface area of the TiO ₂ particles, ie the surface of the uncovered and the fluid-free accessible surface is preferably from 3 to 70%, more preferably> 40 to 60% and in particular about 50% of the surface of the layer.

The introduction of the TiO ₂ particles is carried out in this embodiment, preferably during or after the Patinier process in which z. B. sprayed either a TiO ₂ suspension or a TiO ₂ suspension is applied with a reaction solution for patination. Due to their size, the TiO ₂ particles protrude out of the patina layer due to their size and are therefore available for photocatalytic reactions. In addition, the air can also diffuse into the patina layer and also react there with TiO ₂ , which does not protrude from the layer.

In a further embodiment of the invention, the diameters D of the particles are smaller than the thickness S of the layer, wherein the ratio D: S is about 0.002 to 0.9, preferably 0.01 to 0.8. In this case, the introduction of the TiO ₂ particles takes place at a time when part of the patina layer has already formed. The particles, which are smaller than the patina layer, are thus predominantly on the surface of the layer. Also in this case it can be ensured that a sufficiently large surface (preferably 3 to 70% particularly preferably> 40 to 60%, in particular about 50%) are available as a photocatalytically reactive component. The particle size in this case is preferably 2 nm to about 10 μm and the layer thickness is preferably> 20 to 400 μm, more preferably 40 to 200 μm.

Preferably the determination of the particle size of the particles takes place by the Debeye-Scherrer method in the context of X-ray diffraction and the associated Rietveld refinement.

The method, developed by Peter Debeye and Paul Scherrer and independently by Albert Hull, does not work with single crystals, but with powdered samples. The powder consists of a series of randomly arranged crystallites, so that the lattice planes are randomly arranged in space and so some crystallites always meet the Bragg reflection condition. In addition, the sample rotates about an axis perpendicular to the incident beam. Cone shells made of X-rays, which originate from constructive interference, form around the sample. Around the sample lies a photographic film, on which the conical coats stand out as reflexes. The gloss angle θ can be calculated from the distances of the reflections recorded by the incident beam on the film: x / 2πR = 4θ / 360 °

The distance x of the diffraction reflection on the film from the incident beam is related to the circumference of the camera x / 2πR as the opening angle of the corresponding diffraction cone to 360 °. We also refer to the X-ray diffractometric Rietveld analysis R. Kriegel, Ch. Kaps, Thuringian Materials Day "X-ray diffractometric Rietveld analysis of nanocrystalline precursors and ceramics", Verlag Dr. med. Köster, Berlin 2004, pages 51-56 , the disclosure of which is herein is incorporated by reference.

The titanium dioxide particles may also be porous, optionally with polymodal pore distribution (ie the particle contains micropores, mesopores and / or macropores), thereby increasing their BET surface area. BET surface areas are preferably greater than 5 m ² / g, more preferably 10 to 350 m ² / g, in particular 15 to 150 m ² / g. The determination of the BET surface area is carried out according to DIN 66132 (according to the method of Brunauer, Emmet and Teller).

In a preferred embodiment, the pore volume of the TiO ₂ particles is 10 mm ³ / g to 500 mm ³ / g, in particular between 20 and 300 mm ³ / g. Particularly preferably, the pore volume is between 25 and 150 mm ³ / g. The pore volume is determined by the mercury intrusion method based on the DIN 66133 certainly. The pore radius and thus the classification in micropores, mesopores and macropores, can be determined using the Washburn equation, as in the DIN 66133 specified.

The metal compound has, in particular in the form of a patina layer, a porous and strongly uneven surface, which is significantly larger than that of a relatively smooth metal layer, as described, for example, in US Pat. B. is generated by a galvanic deposition. When this already uneven surface is combined with porous TiO ₂ particles with their large inner surface, the overall result is a much larger reaction surface than TiO ₂ particles, which are deeply embedded in a metal layer. The photocatalytically active surface of TiO ₂ in a layer of a metal compound could be increased in relation to that of TiO ₂ in a pure metal layer.

For the purposes of this invention, the hue of the TiO ₂ particles to be incorporated into the oxide or patina layer may be chosen to suit different color requirements. In the event that the overall aesthetic impression of the TiO ₂ particles interspersed layer or patina layer should not be substantially different from that of a conventional patina without TiO ₂ particles, a hue is selected for the TiO ₂ particles, which does not belong to any significant color changes.

If the color of the layer or patina layer is to be modified specifically in order to produce an overall aesthetic impression which is difficult or impossible to achieve by customary means, the color shade of the TiO ₂ particles can be chosen in such a way that the desired new shade from the mixture of colors of the layer or patina layer and embedded particles arises. The advantages of the invention appear in the fact that the TiO ₂ particles are already photocatalytically active immediately after storage and a time-consuming conversion of, for example, paint components is eliminated.

It is particularly noteworthy that in the case of a copper patina copper ions of the patina can be mobilized by moisture and reach the surface of the TiO ₂ particles. As a result, an increased catalytic activity of the TiO ₂ particles can be provided so that undoped TiO ₂ particles can be used, which need not be previously doped by a complex chemical process with foreign ions, or copper ions. The close spatial contact of TiO ₂ particles with copper oxide in the patina therefore has a positive effect on increasing the photocatalytic activity of TiO ₂ .

In Another preferred embodiment is the surface the layer arranged on the carrier body at least 95%, in particular 100% formed by titanium dioxide. The titanium dioxide is preferably present as a film on the carrier body and further preferred is that the titanium dioxide film is transparent. The carrier body facing layer region contains metal compounds with Cu (I) oxide and / or Cu (II) oxide, the thickness of which adjoins the carrier body Layer area does not exceed 400 nm.

The Generating a surface-covering layer or a titanium dioxide film on the metallic carrier body, for example be carried out by a PVD method or a CVD method, wherein metallic Titanium is deposited on the carrier body and is then oxidized thermally and / or in the presence of oxygen. The use of other oxidants is conceivable here. Around the titanium dioxide film, so arranged on the support Layer, to make transparent, is a small layer thickness advantageous, preferably 5 to 1000 nm. Particularly preferably 10 to 400 nm. Below the titanium dioxide film can also be used according to the invention a metal compound or a patina layer are, thereby in the case of a transparent film, the properties, i. H. of the Color impression of the metallic carrier body or the patina layer is preserved.

It is further preferred if the applied layer or the titanium dioxide film contains microcracks. As a result, water vapor and ambient air can continue to act on the metallic carrier body and form a natural patina layer or widen an already existing patina layer. The titanium dioxide film additionally acts as protection for the underlying metal compounds containing layer or patina layer, so that in the processing of the metallic support body by mechanical means it to a reduced extent to Chipping or damage to the layer comes. The generation of the microcracks can be achieved, for example, by simply reshaping the metallic carrier body.

simultaneously It is also possible together with titanium other metals evaporate in vacuo, for example, Pt, Rh, Mn, Cr, Ru, Ni, Pd, Fe, Co, Ir, Cu, Nb, Zr, Re, Au and Ag. By the after evaporation As a result of the oxidation step, these metals also become oxides converted, so that in the simplest case a mixed oxide of titanium with a further metal or a mixture of metal oxides is present.

The titanium oxidation is preferably carried out at elevated temperature, preferably at 250 ° C. to 600 ° C., more preferably at 300 ° to 550 ° C., in air or in an oxygen stream. Alternatively, an oxidation annealing can also be carried out in the presence of CO / CO ₂ or H ₂ or H ₂ O gas mixtures, if appropriate with N ₂ addition. As a result, a film of TiO ₂ forms on the surface, possibly with embedded metal ions of other metals from the base metal, for. As copper in copper as the parent metal or copper and aluminum in copper aluminum alloys as the parent metal.

The additional metal ions contribute to increasing the photocatalytic activity of the TiO ₂ . A transparent TiO ₂ film additionally serves as a weather-resistant protective layer for the underlying base metal which, for example in the absence of a patina layer, retains its alloy-specific coloration, for example copper-colored or gold-colored in copper-aluminum alloys.

The invention also provides a process for the production of the metallic carrier body according to the invention, comprising the production of a layer containing a metal compound and titanium dioxide on a carrier body. The layer ( 11 ) contains as metal compound copper salt and / or copper oxide and / or copper hydroxide or mixtures thereof and / or intermetallic phases of tin and copper and / or tin-copper compounds.

The layer is produced, for example, by applying a reaction solution or patination solution into which TiO _{2 is} mixed. Preferably, the layer produced should be a patina layer. Particularly preferably, the metallic carrier material is copper or a copper alloy and the patina is a copper patina layer. The production of a synthetic patina is known in the art, for example from the DE 198 09 904 A1 , the subject matter of which is hereby incorporated by reference. As a reaction solution for patination, for example, a solution of copper salts and / or ammonium salts is suitable. Also known, for example, is the use of a 10% ammonium sulfate solution which should act for several hours on copper or a copper alloy. Also known as a patination solution is a combination of ammonium chloride and potassium hydrogen oxalate.

According to the invention the titanium dioxide during or after the application of the reaction solution or be applied after generating the layer. In the first case is the titanium dioxide, preferably in the form of particles of the reaction solution admixed or suspended therein, causing it to be on the metallic Cartridge separates. In another case The titanium dioxide is then applied, if already a part the layer has formed from the reaction solution. A Another possibility is that the titanium dioxide after completion the layer is applied, which then continue to grow can.

In the inventive method can generate the layer further by depositing titanium after the PVD or CVD process and subsequent oxidation of the titanium take place. PVD (physical vapor deposition) or CVD (chemical vapor deposition) method are known in the art. According to the invention deposited together with the titanium other metals with the above methods and then oxidized.

The invention will now be explained in more detail with reference to some not to be understood as limiting the scope to be understood embodiments, in addition to the 1 to 3 Reference is made.

1 shows a metallic carrier body according to the invention 10 from a copper base metal and a patina layer 11 into the TiO ₂ particles 12 are embedded, whose diameter is greater than the layer thickness.

2 shows a metallic carrier body 10 from a copper base metal with a patina layer 11 into the TiO ₂ particles 12 are embedded, whose diameter is smaller than the layer thickness of the patina layer 11 but these are on the surface of the patina layer 11 are located.

3 shows a carrier body according to the invention 10 from a copper base metal with a patina layer 11 into the TiO ₂ particles 12 are embedded, which are much smaller than the layer thickness of the patina layer 11 and wherein these TiO ₂ particles 12 following the generation of the patina layer 11 were applied.

EXAMPLES

Example 1:

Novel factory patinated or oxidized Cu-band with pollutant decomposing property by embedded TiO ₂ particles.

A sheet of copper 0.6 mm thick has on one surface an artificially produced green patina layer of 30 μm average thickness (see 1 ). This patina has an intimate connection with the base material. In this layer TiO ₂ particles are embedded with a diameter of 40 microns, so that the surface of the uncovered TiO ₂ particles has a proportion of the total surface of the patinated surface of 45%. The incorporation of the TiO ₂ particles takes place during the Patinierprozesses by a TiO ₂ suspension is applied with the reaction solution for patination. The TiO ₂ particles are mainly near the surface and are only partially enveloped by the surrounding patina layer. This free surface of the TiO ₂ particles is then available for photocatalytic reactions with air pollutants such as NO _x . The patina layer represents an intimate connection of the TiO ₂ particles with the base material.

Special advantage:

• - Relatively coarse TiO ₂ particles can be used, which require less effort in the production than fine-grained material (less grinding costs).
• - large contact surface to the surrounding Patina, the particularly strong binding of the particles into the patina layer allows (high abrasion resistance).

Example 2:

TiO ₂ particles with a diameter of 20 nm (see 2 ), ie smaller than the layer thickness S of the patina with 100 microns, are abandoned at a later date than the first patination solution, as soon as a first thin adherent patina layer has formed on the base metal. As the patina layer continues to grow, these later deposited TiO ₂ particles are partially trapped by the patina layer and present on the patina surface with a partial uncovered particle surface.

Special advantage:

• - The TiO ₂ particles are present only in the near-surface region, therefore less TiO ₂ particles are required than in Example 1, which means a saving of material.

Example 3:

Already provided with a patina tapes are sprayed with a TiO ₂ -containing suspension, which favors the patina growth. The TiO ₂ particles deposited thereby on the original patina surface are partially enclosed and fixed by the further growing patina layer and are available with the free surface for photocatalytic reactions (see 3 ).

Special advantage:

Already Existing patina layers can be photocatalytic Reactions be subsequently opened up.

Example 4:

Novel Cu-band with pollutant-decomposing property by surface-deposited TiO ₂ .

Construction: Starting material is a sheet or strip of copper or a copper alloy with 0.5 mm thickness. This sheet or band points to the surface an approximately 50 nm thick oxide layer containing Cu (I) oxide and / or Cu (II) oxide on. The oxide layer can, for example, by a Heat treatment, z. B. by aging in air at 200 ° C, be generated. The sheet metal or ribbon having the oxide layer is steamed with Ti in a vacuum (PVD method). Alternatively, you can the Ti layer can also be deposited by the CVD method. The Thickness is in the range of 100 nm. The Ti film then becomes in a following additional process step by oxygen the ambient air converted to Ti oxide. The reaction rate depends on the temperature and the oxygen partial pressure from.

The Ti oxidation is carried out at elevated temperature (500 ° C) in air. This converts the Ti at the strip surface into a film of TiO ₂ , which is transparent. It is an opaque transparent TiO ₂ layer on copper-based base material, which offers maximum protection against discoloration by weathering at the same time mitigated activity.

Special advantage:

• - A transparent TiO ₂ film also serves as a weather-resistant protective layer for the underlying base metal, which thereby retains its alloy-specific color, for. B. Cu-colored or gold-colored in CuAl alloys.
• - Good adhesion of Ti oxide layer on metallic surfaces; the good adhesion is achieved in the following way: It has been observed that An oxide layer on a metal strip or sheet can then be anchored with good adhesion, if this oxide layer grows on the base metal by an oxidizing heat treatment and the oxide layer does not exceed a certain critical thickness for the adhesion.
• - This is achieved by a Cu oxide-containing intermediate layer of <400 nm, the because of the small thickness almost transparent acts, and one about it arranged thin Ti oxide film, by the oxidation a 100 nm thick Ti film is formed.
• Improved reactivity of the TiO ₂ layer: While the Ti oxide film is formed by oxidation at elevated temperature, Cu oxide particles from the immediately adjacent Cu oxide-containing intermediate layer are incorporated into this film, thereby increasing the reactivity of the Ti oxide becomes.

Example 5:

Novel Cu-band with pollutant-decomposing property by surface-deposited TiO ₂ .

Construction: Starting material is a sheet or strip of copper or a copper alloy with 0.6 mm thickness. This sheet is vacuumed with Ti (PVD method) steamed. The thickness of the layer is in the range of 100 nm.

In a subsequent heat treatment at elevated temperature (600 ° C), there is a diffusion of Cu atoms in the Ti layer, whereby the Ti layer is firmly anchored to the base metal. Subsequently, the Ti layer is converted into Ti oxide in an oxidizing gas atmosphere (eg O 2 + N 2) at elevated temperature (500 ° C.). The Cu atoms diffused into the Ti layer are thereby converted to Cu oxide, and a Cu oxide-containing intermediate layer is formed between the Ti oxide-rich surface, which provides the Cu ions for improved reactivity of the TiO ₂ .

Special advantage:

See example 4

Example 6:

A microcracked transparent TiO ₂ layer on a metallic basis is generated for increased catalytic reactivity of the TiO ₂ cover layer. The preparation is carried out according to Example 4, wherein the microcracks are produced by a small deformation.

Special advantage:

Microcracks mobilize small amounts of Cu ions under the influence of the weather and thus reach the surface of the TiO ₂ film, where they increase the reactivity of the TiO ₂ . The parent metal, which is in the vicinity of a microcrack under the intact TiO ₂ layer, is protected from discoloration by weathering.

The extent of the cracking can thus optimize the photocatalytic reactivity of the TiO ₂ film in relation to the protective effect of the base metal.

Example 7:

On a copper surface, first a film of metallic Ti with proportions of Cu is evaporated in a vacuum. In a subsequent oxidation step, both the Ti and the copper contained in the Ti layer are oxidized, so that a TiO ₂ film is formed with embedded copper oxides. The type and concentrations of the additionally deposited in addition to the Ti metals was chosen so that the photocatalytic reactivity of TiO _{2 are} optimal or higher than in pure Ti.

Special advantage:

higher Benefits of purifying the air compared to pure Ti.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• WO 99/33564 [0003]
• - EP 1835051 A2 [0009]
• - DE 19809904 A1 [0048]

Cited non-patent literature

• - DIN EN 988 [0007]
• - R. Kriegel, Ch. Kaps, Thuringian Materials Day "X-ray diffractometric Rietveld analysis of nanocrystalline precursors and ceramics", Verlag Dr. med. Köster, Berlin 2004, pages 51-56 [0034]
• - DIN 66132 [0035]
• - DIN 66133 [0036]
• - DIN 66133 [0036]

Claims (21)

Metallic carrier body ( 10 ), which consists of a metal alloy containing at least 0.01% by weight of copper, comprising one on the support body ( 10 ) layer ( 11 ), characterized in that the layer ( 11 ) contains as the metal compound copper salt and / or copper oxide and / or copper hydroxide or mixtures thereof and / or intermetallic phases of tin and copper and / or tin-copper compounds and titanium dioxide ( 12 ) and wherein 3 to 100% of the surface of the layer ( 11 ) of titanium dioxide ( 12 ) are formed. Carrier body ( 10 ) according to claim 1, characterized in that the carrier body consists of a metal alloy containing at least 0.5 wt .-% copper Carrier body ( 10 ) according to claim 1 or 2, characterized in that on the carrier body ( 10 ) layer ( 11 ) is a patina layer. Carrier body ( 10 ) according to one of claims 1 to 3, characterized in that the titanium dioxide ( 12 ) in the form of particles in the layer ( 11 ) is present. Carrier body ( 10 ) according to claim 4, characterized in that the diameter D of the particles is greater than the thickness S of the layer ( 11 ). Carrier body ( 10 ) according to claim 5, characterized in that the ratio D to S is about 1.02 to 1.5. Carrier body ( 10 ) according to claim 4, characterized in that the diameter D of the particles is smaller than the thickness S of the layer ( 11 ). Carrier body ( 10 ) according to claim 7, characterized in that the ratio D to S is about 0.002 to 0.9 Carrier body ( 10 ) according to one of claims 1 to 3, characterized in that the surface of the on the support body ( 10 ) layer ( 11 ) to 95% to 100% of titanium dioxide ( 12 A layer region adjacent to the carrier body contains Cu (I) oxide and / or Cu (II) oxide, wherein the layer thickness of the layer region adjoining the carrier body does not exceed 400 nm. Carrier body ( 10 ) according to claim 9, characterized in that the titanium dioxide ( 12 ) is present as a film. Carrier body ( 10 ) according to claim 9 or 10, characterized in that the layer ( 11 ) and / or the titanium dioxide film is transparent. Carrier body ( 10 ) according to one of claims 9 to 11, characterized in that the layer ( 11 ) and / or the titania film contains microcracks. Carrier body ( 10 ) according to one of claims 9 to 12, characterized in that the carrier body is tinned. Carrier body ( 10 ) according to one of the preceding claims, characterized in that the metallic carrier body ( 10 ) is a sheet or tape. Use of a metallic carrier body ( 10 ) according to one of claims 1 to 14 as a pollutant-reducing component. Use according to claim 15 as a component in the high and civil engineering, as roofing or as facade cladding. Method for producing a metallic carrier body ( 10 ) according to one of claims 1 to 14, comprising producing a layer ( 11 ) containing a copper-containing metal compound and titanium dioxide ( 12 ), on a carrier body. Method according to claim 17, characterized in that the production of the layer ( 11 ) by applying a reaction solution. A method according to claim 18, characterized in that the deposition of titanium dioxide ( 12 ) during or after the application of the reaction solution or after the formation of the layer ( 11 ) he follows. Method according to claim 17, characterized in that the production of the layer ( 11 ) by depositing titanium according to the PVD or CVD method and subsequent oxidation of the titanium. Method according to claim 20, characterized in that that deposited further metals together with titanium and then be oxidized.