Effect pigments

Abstract

To prepare reproducible opaque effect pigments with a metallic luster which are transparent to electromagnetic radiation.SOLUTION: The invention relates to opaque fluoride-doped effect pigments having a metallic luster based on flake-form substrates, a process for preparation of the pigments, and the use thereof, in particular in automotive paints and cosmetic formulations.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to opaque fluoride-doped effect pigments with metallic luster based on a flake-like substrate, to a process for the preparation of said pigments, and to their use, especially in automotive paint and cosmetic formulations. [Background technology]

[0002] Effect pigments are increasingly used in the automotive sector, in the coloring of plastics, in cosmetics and also in the printing sector. Effect pigments are intended to impart a certain luster or a certain color effect to the product colored with them. Typically, effect pigments are substrates, for example comprising metals, mica or synthetic flakes of SiO2, glass or Al2O3, coated with one or more layers, for example comprising metals or metal oxides. Metal oxides are frequently used layer materials, in particular because they can be applied to the substrate by precipitation and are very substantially chemically inert. Pigments with new and interesting color effects are obtained, inter alia, by reduction of the metal oxide layer of the interference pigment. The reducing agents used are preferably hydrogen, ammonia, carbon, carbon monoxide, hydrocarbons, non-metallic hydrides (e.g. NaBH4), or metals. Thus, for example, WO 93 / 19131 describes the reduction calcination of TiO2-coated flaky substrates using a solid reducing agent in a non-oxidizing atmosphere, in which a layer structure is formed in which the content of Ti oxide gradually increases towards the substrate and the atoms of the reducing agent are gradually used towards the outside, as long as the reducing agent can be integrated into the titanium oxide structure or remains at the grain boundaries of the titanium oxide crystallites. U.S. Patent No. 4,623,396 discloses the reduction of TiO2 / mica pigments in the presence of a reducing gas mixture, where mica flakes are coated with two layers of titanium compounds, one on top of the other, where the second layer, disposed on top of the first layer, consists of TiO2, and the first layer, disposed directly on the mica particles, consists of titanium compounds, e.g., lower titanium oxides, titanium oxynitrides, and mixtures of titanium compounds and TiO2. An outer TiO2 layer is formed by subsequent heating under oxidizing conditions, so that the layer of TiO2 is converted to TiO2. 2-x It is generated from the outside on top of the An essential disadvantage of effect pigments known from the prior art, prepared under reducing conditions, is the inhomogeneous calcination result and thus the reproducibility of the pigments. A further disadvantage is the use of solid reducing agents, which leads to contamination of the layer reduced with said reducing agents and thus causes undesirable changes in the actual desired color effect. Reduction using metals is also a disadvantage, since additional components are introduced into the coating, which can likewise lead to undesirable changes in the properties of the pigments. Summary of the Invention

[0003] It is therefore an object of the present invention to prepare reproducible opaque effect pigments with metallic luster which do not have the abovementioned disadvantages and which are at the same time transparent to electromagnetic radiation. Surprisingly, it has been found that effect pigments comprising at least one fluoride-doped titanium dioxide layer calcined under reducing conditions have a metallic luster and, in contrast to aluminum pigments, are transparent to electromagnetic radiation. The pigments according to the invention can be easily and reproducibly prepared and have significantly improved hiding power compared to the starting pigments.

[0004] The present invention includes at least one TiO2 layer, in which TiO2 is added to the TiO2. III+ and to effect pigments based on flake-shaped substrates, characterized in that they are doped with fluoride. The effect pigments according to the invention exhibit a darker masstone than the starting pigment, usually have a bluish metallic luster, and are transparent to electromagnetic radiation. The invention also relates to the use of the pigments according to the invention in inks, powder coatings, paints, especially automotive paints and radar-transparent finishes, as well as in electrostatic dissipative formulations, in printing inks, security printing inks, plastics, as absorbents for laser marking and laser welding, in cosmetic formulations, especially for high-temperature applications, for example for the pigmentation of glazes and ceramics. The pigments according to the invention are also suitable for the preparation of pigment preparations and for the preparation of dry preparations, for example for the preparation of ceramic colors, granules, chips, pellets, briquettes, etc. [Brief description of the drawings]

[0005] [Figure 1] This is the definition of the angle in a multi-angle spectrophotometer. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0006] Suitable base substrates for the effect pigments according to the invention are translucent and transparent flake-shaped substrates.Preferred substrates are phyllosilicate flakes, SiC flakes, TiC flakes, WC flakes, B4C flakes, BN flakes, graphite flakes, TiO2 flakes and Fe2O3 flakes, doped or undoped Al2O3 flakes, doped or undoped glass flakes, doped or undoped SiO2 flakes, TiO2 flakes, BiOCl, and mixtures thereof.From the group of phyllosilicates, particular preference is given to natural and synthetic mica flakes, muscovite, talc, and kaolin.The synthetic mica used as substrate is preferably fluorphlogopite or Znphlogopite. The pigments according to the invention are preferably based on a substrate selected from the group of synthetic or natural mica flakes, phyllosilicates, glass flakes, borosilicate flakes, SiO2 flakes, Al2O3 flakes, TiO2 flakes, graphite flakes, and / or BiOCl flakes. The glass flakes can consist of all types of glass known to those skilled in the art, as long as they are temperature-stable in the firing range used. Suitable glasses are, for example, quartz, A-glass, E-glass, C-glass, ECR-glass, used glass, alkali borate glass, alkali silicate glass, borosilicate glass, Duran® glass, laboratory glass, or optical glass. The refractive index of the glass flakes is preferably 1.45 to 1.80, particularly preferably 1.50 to 1.70.The glass substrate is particularly preferably made of C glass, ECR glass or borosilicate glass. The synthetic substrate flakes, such as glass flakes, SiO2 flakes, Al2O3 flakes, etc., may be doped or undoped. If doped, the doping is preferably Al, N, B, Ti, Zr, Si, In, Sn or Zn, or mixtures thereof. Furthermore, further ions from the group of transition metals (V, Cr, Mn, Fe, Co, Ni, Cu, Y, Nb, Mo, Hf, Ta, W) and ions from the group of lanthanides may act as dopants. In the case of Al2O3, the substrate is preferably undoped or doped with TiO2, ZrO2 or ZnO. The Al2O3 flakes are preferably corundum. Suitable Al2O3 flakes are preferably doped or undoped α-Al2O3 flakes, in particular α-Al2O3 flakes doped with TiO2 or ZrO2.

[0007] If the substrate is doped, the doping proportion is preferably from 0.01 to 5% by weight, in particular from 0.1 to 3% by weight, based on the substrate. The size of the base substrate is not critical per se and can be adapted to the particular application. In general, the flake substrate has a thickness of 0.05 to 5 μm, in particular 0.1 to 4.5 μm. Substrates of different particle sizes can also be used. Particularly preferred are mixtures of mica fractions N (10-60 μm), F (5-20 μm) and / or M (<15 μm). Even more preferred are N and S fractions (10-130 μm) and F and S fractions (5-130 μm). Typical example of particle size distribution (measured with a Malvern Mastersizer 3000): D 10 : 1 to 50 μm, in particular 2 to 45 μm, very particularly preferably 5 to 40 μm D 50 : 7 to 275 μm, in particular 10 to 200 μm, very particularly preferably 15 to 150 μm D 90 : 15 to 500 μm, in particular 25 to 400 μm, very particularly preferably 50 to 200 μm.

[0008] In this patent application, "high refractive index" means a refractive index of ≧1.8, and "low refractive index" means a refractive index of <1.8. The flake-shaped substrate is preferably completely covered with one or more layers. In a preferred embodiment, the support material of the effect pigments can be coated with one or more transparent, translucent and / or opaque layers comprising metal oxides, metal oxide hydrates, metal suboxides, metals, metal fluorides, metal nitrides, metal oxynitrides or mixtures of these materials. The metal oxide, metal oxide hydrate, metal suboxide, metal, metal fluoride, metal nitride, metal oxynitride layers or mixtures thereof can have a low refractive index (refractive index < 1.8) or a high refractive index (refractive index ≧ 1.8). Suitable metal oxides and metal oxide hydrates are all metal oxides or metal oxide hydrates known to the skilled artisan, such as aluminum oxide, aluminum oxide hydrate, silicon oxide, silicon oxide hydrate, iron oxide, tin oxide, cerium oxide, zinc oxide, zirconium oxide, chromium oxide, titanium oxide, etc., in particular titanium dioxide, titanium oxide hydrate and mixtures thereof, such as Fe / Ti mixed oxides. A usable metal suboxide is, for example, titanium suboxide. A suitable metal fluoride is, for example, magnesium fluoride. A usable metal nitride or metal oxynitride is, for example, a nitride or oxynitride of the metals titanium, silicon, zirconium and / or tantalum. Preferably, a metal oxide, metal, metal fluoride and / or metal oxide hydrate layer, very particularly preferably a metal oxide and / or metal oxide hydrate layer, is applied to the support. Furthermore, there may also be multilayer structures with high and low refractive index metal oxide, metal oxide hydrate, metal or metal fluoride layers, preferably alternating high and low refractive index layers. Particularly preferred are layer packages with high and low refractive index layers, one or more of which may be applied to the support. The order of the high and low refractive index layers can be matched to the support in order to incorporate the support into the multilayer structure. In further embodiments, layers of metal oxides, metal silicates, metal oxide hydrates, metal suboxides, metals, metal fluorides, metal nitrides, metal oxynitrides can be mixed or doped with colorants, so long as the layers are stable in the reduction process. The low refractive index layer, having a refractive index of n≧1.8, preferably n≧2.0, preferably comprises a metal oxide selected from the group of TiO2, ZrO2, ZnO, SnO2, Cr2O3, Ce2O3, BiOCl, Fe2O3, Fe3O4, FeO(OH), Ti suboxides (partially reduced TiO2 and lower oxides with oxidation states <4 to 2, e.g. Ti3O5, Ti2O3 to TiO), titanium oxynitrides and titanium nitrides, alkaline earth metal titanates MTiO3 (M=Ca, Sr, Ba), CoO, Co2O3, Co3O4, VO2, VO3, NiO, WO3, MnO, Mn2O3 or mixtures of the above oxides. The low refractive index layer, having a refractive index of n<1.8, preferably n<1.7, preferably comprises a metal oxide selected from the group of SiO2, MgO.SiO2, CaO.SiO2, Al2O3.SiO2, B2O3.SiO2 or mixtures of the above mentioned compounds. Furthermore, the silicate layer may be doped with alkaline earth or alkali metal ions.

[0009] Suitable colorants or other elements are, as long as they are stable at the reducing temperature, for example inorganic color pigments such as colored metal oxides (e.g. magnetite, chromium(III) oxide), color pigments such as Thaenard Blue (Co-Al spinel), or elements such as yttrium or antimony, and pigments of the perovskite, pyrochlore, rutile and spinel structural classes in general. Pearlescent pigments comprising the abovementioned layers show a high chromatic diversity with respect to their masstones and can often show angle-dependent color changes (color flop) due to interference.

[0010] The thickness of the metal oxide, metal oxide hydrate, metal suboxide, metal, metal fluoride, metal nitride, metal oxynitride layer or mixtures thereof on the supporting substrate is usually 3 to 1000 nm, and in the case of the metal oxide, metal oxide hydrate, metal suboxide, metal fluoride, metal nitride, metal oxynitride or mixtures thereof, it is preferably 20 to 200 nm. All effect pigments known to the person skilled in the art that are based on flake-shaped substrates containing one or more layers, preferably metal oxide layers, are suitable, as long as they have at least one titanium dioxide layer, preferably with a layer thickness of 20 to 500 nm, in particular 30 to 200 nm, very particularly preferably 40 to 60 nm. The TiO2 layer is preferably the outer layer of the base substrate. However, for the effect pigments according to the invention, all commercially available effect pigments can also be used, as long as they have at least one TiO2 layer, in particular an outer TiO2 layer. The TiO2-layer may be in the rutile or anatase modification. The TiO2-layer is preferably in the rutile modification. In further embodiments, the TiO2-layer may be additionally doped, for example with niobium, zirconium, magnesium, calcium, strontium, barium, zinc, indium, tin, antimony.

[0011] Particularly preferred base pigments for fluoride doping of the TiO2 layer under mild reducing conditions have the following structure: -Base material + TiO2 -Base material + SnO2 + TiO2 -Substrate + TiO2 + SiO2 + TiO2 -Substrate +SnO2+TiO2+SiO2+SnO2+TiO2 -Base material+TiO2+MgO+TiO2 -Substrate +SnO2+TiO2+MgO+SnO2+TiO2 -Base material +TiO2+CaO+TiO2 -Substrate+SnO2+TiO2+CaO+SnO2+TiO2 -Base material+TiO2+SrO+TiO2 -Substrate +SnO2+TiO2+SrO+SnO2+TiO2 -Base material+TiO2+BaO+TiO2 -Substrate+SnO2+TiO2+BaO+SnO2+TiO2 -Base material+TiO2+ZnO+TiO2 -Base material+SnO2+TiO2+ZnO+SnO2+TiO2

[0012] Very particularly preferred effect pigments have the following layer structure: -Natural mica flakes + TiO2 -Natural mica flakes + SnO2 + TiO2 -Natural mica flakes + TiO2 + SiO2 + TiO2 -Natural mica flakes + SnO2 + TiO2 + SiO2 + SnO2 + TiO2 -Natural mica flakes + TiO2 + MgO + TiO2 -Natural mica flakes + SnO2 + TiO2 + MgO + SnO2 + TiO2 -Natural mica flakes + TiO2 + CaO + TiO2 -Natural mica flakes + SnO2 + TiO2 + CaO + SnO2 + TiO2 -Natural mica flakes + TiO2 + SrO + TiO2 -Natural mica flakes + SnO2 + TiO2 + SrO + SnO2 + TiO2 -Natural mica flakes + TiO2 + BaO + TiO2 -Natural mica flakes + SnO2 + TiO2 + BaO + SnO2 + TiO2 -Natural mica flakes + TiO2 + ZnO + TiO2 -Natural mica flakes + SnO2 + TiO2 + ZnO + SnO2 + TiO2 -Synthetic mica flakes + TiO2 -Synthetic mica flakes + SnO2 + TiO2 -Synthetic mica flakes + TiO2 + SiO2 + TiO2 -Synthetic mica flakes + SnO2 + TiO2 + SiO2 + SnO2 + TiO2 -Synthetic mica flakes + TiO2 + MgO + TiO2 -Synthetic mica flakes + SnO2 + TiO2 + MgO + SnO2 + TiO2 -Synthetic mica flakes + TiO2 + CaO + TiO2 -Synthetic mica flakes + SnO2 + TiO2 + CaO + SnO2 + TiO2 -Synthetic mica flakes + TiO2 + SrO + TiO2 -Synthetic mica flakes + SnO2 + TiO2 + SrO + SnO2 + TiO2 -Synthetic mica flakes + TiO2 + BaO + TiO2 -Synthetic mica flakes + SnO2 + TiO2 + BaO + SnO2 + TiO2 -Synthetic mica flakes + TiO2 + ZnO + TiO2 -Synthetic mica flakes + SnO2 + TiO2 + ZnO + SnO2 + TiO2 -SiO2 flakes + TiO2 -SiO2 flakes + SnO2 + TiO2 -SiO2 flakes + TiO2 + SiO2 + TiO2 -SiO2 flakes + SnO2 + TiO2 + SiO2 + SnO2 + TiO2 -SiO2 flakes + TiO2 + MgO + TiO2 -SiO2 flakes + SnO2 + TiO2 + MgO + SnO2 + TiO2 -SiO2 flakes + TiO2 + CaO + TiO2 -SiO2 flakes + SnO2 + TiO2 + CaO + SnO2 + TiO2 -SiO2 flakes + TiO2 + SrO + TiO2 -SiO2 flakes + SnO2 + TiO2 + SrO + SnO2 + TiO2 -SiO2 flakes + TiO2 + BaO + TiO2 -SiO2 flakes + SnO2 + TiO2 + BaO + SnO2 + TiO2 -SiO2 flakes + TiO2 + ZnO + TiO2 -SiO2 flakes + SnO2 + TiO2 + ZnO + SnO2 + TiO2 -Al2O3 flakes + TiO2 -Al2O3 flakes + SnO2 + TiO2 -Al2O3 flakes + TiO2 + SiO2 + TiO2 -Al2O3 flakes + SnO2 + TiO2 + SiO2 + SnO2 + TiO2 -Al2O3 flakes + TiO2 + MgO + TiO2 -Al2O3 flakes + SnO2 + TiO2 + MgO + SnO2 + TiO2 -Al2O3 flakes + TiO2 + CaO + TiO2 -Al2O3 flakes + SnO2 + TiO2 + CaO + SnO2 + TiO2 -Al2O3 flakes + TiO2 + SrO + TiO2 -Al2O3 flakes + SnO2 + TiO2 + SrO + SnO2 + TiO2 -Al2O3 flakes + TiO2 + BaO + TiO2 -Al2O3 flakes + SnO2 + TiO2 + BaO + SnO2 + TiO2 -Al2O3 flakes + TiO2 + ZnO + TiO2 -Al2O3 flakes + SnO2 + TiO2 + ZnO + SnO2 + TiO2 -Glass flakes + TiO2 -Glass flakes + SnO2 + TiO2 -Glass flakes + TiO2 + SiO2 + TiO2 -Glass flakes + SnO2 + TiO2 + SiO2 + SnO2 + TiO2 -Glass flakes + TiO2 + MgO + TiO2 -Glass flakes + SnO2 + TiO2 + MgO + SnO2 + TiO2 -Glass flakes + TiO2 + CaO + TiO2 -Glass flakes + SnO2 + TiO2 + CaO + SnO2 + TiO2 -Glass flakes + TiO2 + SrO + TiO2 -Glass flakes + SnO2 + TiO2 + SrO + SnO2 + TiO2 -Glass flakes + TiO2 + BaO + TiO2 -Glass flakes + SnO2 + TiO2 + BaO + SnO2 + TiO2 -Glass flakes + TiO2 + ZnO + TiO2 -Glass flakes + SnO2 + TiO2 + ZnO + SnO2 + TiO2 "TiO2" means a doped or undoped TiO2 layer. The TiO2 layer is preferably undoped. An undoped rutile layer is particularly preferred.

[0013] The metal oxide layer(s) are preferably applied to the substrate flakes by wet-chemical methods, whereby wet-chemical coating methods developed for the production of pearlescent pigments can be used, such as those described, for example, in US Pat. No. 3,087,828, US Pat. No. 3,087,829, US Pat. No. 3,553,001, DE-A-1,467,468, DE-A-1,959,988, DE-A-2,009,566, DE-A-2,214,545, DE-A-2,215,191, DE-A-2,244,298, W.G. These are described in JP-A-2 313 331, JP-A-2 522 572, JP-A-3 137 808, JP-A-3 137 809, JP-A-3 151 343, JP-A-3 151 354, JP-A-3 151 355, JP-A-3 211 602, JP-A-3 235 017, JP-A-19 618 568, EP-A-0 659 843 or also in further patent documents and other publications known to the person skilled in the art. In the case of wet coating, the substrate flakes are suspended in water and one or more hydrolyzable metal salts are added at a pH suitable for hydrolysis, selected so that the metal oxides or metal oxide hydrates are precipitated directly on the flakes without secondary precipitation. The pH is usually kept constant by simultaneous metered addition of a base and / or an acid. The effect pigments are then separated, washed and dried and optionally calcined. The calcination temperature can be optimized with respect to the coating present in each case. In general the calcination temperature is between 250 and 1000°C, preferably between 350 and 900°C. If desired, the pigments can be separated after application of the individual coatings, dried and optionally calcined and then resuspended for the deposition of further layers. For the application of the SiO2 layer, the method described in DE 196 18 569 A1 can be used. For the production of the SiO2 layer, a sodium or potassium waterglass solution is preferably used. Furthermore, the coating can also be carried out by gas phase coating in a fluidized bed reactor, in which case the methods proposed, for example, in EP-A-0 045 851 and EP-A-0 106 235 for the preparation of pearlescent pigments can likewise be used.

[0014] For the application of titanium dioxide, the method described in US Pat. No. 3,553,001 is preferably used. In this method, an aqueous solution of an inorganic titanium salt is slowly added to a suspension of the optionally already precoated substrate, heated to about 50-100° C., in particular 70-80° C., the pH being kept substantially constant at 0.5-5, in particular about 1.5-2.5, by simultaneous metered addition of a base. As soon as the desired layer thickness of TiO2 oxide hydrate is reached, the addition of the titanium salt solution and the base is stopped. This method, also known as the titration method, has the special feature that there is no excess of titanium salt, but instead only the amount per time unit necessary for a uniform coating of hydrated TiO2 is always provided, which may even adhere to the surface of the substrate to be coated. Thus, there are no hydrated titanium dioxide particles in the solution that do not deposit on the surface to be coated. The hue of the pigment can be varied in a very wide range by varying the amount of coating or the layer thickness resulting from said coating. Fine tuning for a particular hue can be achieved not only by the choice of amount but also by approaching the desired color under visual or methodological control.

[0015] Fluoride doping of the TiO2 layers on the base pigment is carried out by simultaneously reducing the TiO2 layers of the starting pigment in the presence of a reducing agent and a fluoride donor. If the base pigment contains multiple TiO2 layers, fluoride incorporation into the TiO2 crystal lattice occurs only in the outer TiO2 layers under reducing conditions. Fluoride doping at the anion sites of TiO2 induces positive charge centers in the TiO2 lattice structure, which in turn induces Ti 4+ From Ti 3+ This simplifies the reduction to Ti, i.e., the required reduction temperature is lower than that of Ti, where no fluoride donor is present. 4+ From Ti 3+ The milder reduction conditions areIII+ This increases uniformity within the doped and fluoride-doped TiO2 layers and at the same time increases reproducibility. Suitable reducing agents are solid reducing agents known to those skilled in the art, such as alkaline earth metals, B, Al, Si, Zn, Fe, LiH, CaH2, NaBH4, MgSi, MgSi2, Ca2Si, CaSi2, etc. The reducing agent used is preferably Si. The proportion of reducing agent is preferably 0.5 to 5% by weight, in particular 0.8 to 2% by weight, very preferably 0.9 to 1.2% by weight, based on the base pigment. Suitable fluoride donors are, for example, inorganic fluorides (e.g. CaF2, MgF2, NaF, NH4F, etc.), organic fluorine compounds (e.g. polytetrafluoroethylene, etc.), natural and synthetic fluorine-containing minerals (e.g. synthetic fluorophlogopite (=synthetic mica), etc.). The proportion of fluoride donor, based on the base pigment, is preferably 0.01 to 3% by weight, in particular 0.01 to 1% by weight and very particularly preferably 0.03 to 0.3% by weight. The reduction reaction and doping can be carried out using, for example, N2, Ar, He, CO2, CO, forming gas (e.g., 95:5 (v / v) N2:H2), C x H y The reaction is carried out in an inert or reducing atmosphere such as H2, with N2 or Ar being preferred. The reduction is preferably carried out at a temperature of 700 to 1000° C., preferably 700 to 950° C., particularly 750 to 850° C., for a time period of more than 10 minutes, preferably more than 15 to 60 minutes. The reduction temperature can be further lowered by the presence of a molten salt, such as, for example, an alkali metal / alkaline earth metal halide (such as, for example, CaCl2 or MgCl2). The proportion of the molten salt is preferably 0.01 to 5% by weight, in particular 0.01 to 3% by weight, very particularly preferably 0.03 to 1.5% by weight, based on the base pigment. However, the temperature cannot be lowered arbitrarily, since it is limited by the melting point of the added halide. That is, for example, CaCl2 melts at 772°C and MgCl2 at 714°C, and the reduction temperature must be equal to or higher than the melting point of the molten salt. In a particularly preferred embodiment, the reduction of the starting pigment is carried out using Si, CaF2 and CaCl2. However, the reduction methods known from the prior art differ significantly in procedure from the reduction method according to the invention. The degree of doping is such that the final pigment is doped with at least one fluoride and reduction-fired, of the formula TiF y O 2-x-y titanium dioxide is selected to be included, where x and y are defined as follows: 0.00001 < y < 0.05, preferably 0.0001 < y < 0.01, particularly preferably 0.001 < y < 0.005, and 0.00001 < x < 0.1, particularly preferably 0.0001 < x < 0.03. The TiO2 crystal structure is not changed by doping with fluoride and Ti 3+ i.e., there is no titanium suboxide.

[0016] The present invention also relates to a method for preparing an effect pigment according to the present invention, wherein an effect pigment based on a flaky substrate having at least one TiO2 layer is reacted with at least one solid reducing agent at a temperature of 700 to 900 °C for 15 to 60 minutes in a non-oxidizing gas atmosphere in the presence of a fluoride donor and optionally at least one molten salt. The degree of darkening by reduction can be controlled by both the proportion of the reducing agent and the proportion of the fluoride donor in the reaction mixture. However, the proportion of the fluoride donor cannot be arbitrarily increased.

[0017] To increase the light, water and weather stability, it is often advisable to subject the effect pigments according to the invention to an inorganic or organic post-coating or post-treatment, depending on the field of application. Post-coatings or post-treatments which come into consideration are, for example, the methods described in DE-A-2215191, DE-A-3151354, DE-A-3235017 or DE-A-3334598. This post-coating further increases the chemical and photochemical stability or simplifies the handling of the effect pigments, in particular their incorporation into various media. To improve the wetting, dispersibility and / or compatibility with the user media, a functional coating comprising SnO2, Al2O3 or ZrO2 or mixtures thereof can be applied to the pigment surface. Furthermore, organic post-coating is possible, for example with silanes, as described in EP 0 090 259 A, EP 0 634 459 A, WO 99 / 57204 A, WO 96 / 32446 A, WO 99 / 57204 A, U.S. Pat. No. 5,759,255 A, U.S. Pat. No. 5,571,851 A, WO 01 / 92425 A or by JJ Pomjee, Philips Technical Review, Vol. 44, No. 3, 81 ff. and PH Harding JC Berg, J. Adhesion Sci. Technol. Vol. 11 No. 4, pp. 471-493. Further examples of organic post-coatings can be found, for example, in EP 0 632 109, U.S. Pat. No. 5,759,255, DE 4 317 019 A1, DE 3 929 423 A1, DE 3 235 017 A1, EP 0 492 223 A1, EP 0 342 533 A1, EP 0 268 918 A1, EP 0 141 174 A1, EP 0 764 191 A1, WO 98 / 13426 A1 or EP 0 465 805 A1, the disclosure contents of which are incorporated herein by reference.Pigments comprising an organic coating, for example organosilanes or organotitanates or organozirconates, furthermore exhibit, in addition to the optical properties already mentioned, an improved stability to weathering influences, such as moisture and light, which is of particular interest, in particular in the industrial coatings and automotive sectors. The stabilization can be improved by the inorganic components of an additional coating. The substances applied in this case only comprise 0.1 to 5% by weight, preferably 0.5 to 3% by weight, of the total effect pigment. The respective proportions for the additional stabilizing coatings must be selected so that, overall, the optical properties of the effect pigments according to the invention are only slightly or not at all affected.

[0018] The pigments according to the invention have a wide variety of applications.The invention therefore also relates to the use of the effect pigments according to the invention in cosmetics, paints, powder coatings, inks, plastics, films, in security printing, in security features on documents and identity cards, for laser marking, as electrostatic dissipative pigments, for seed coloring, for food coloring, in pharmaceutical coatings and for pigment preparation and drying preparations. In the case of cosmetics, the effect pigments according to the invention are particularly suitable for cosmetic products and formulations for make-up, such as, for example, nail varnishes, colouring powders, lipsticks or eye shadows, soaps, toothpastes, etc. The effect pigments according to the invention can of course be combined into formulations together with cosmetic raw materials and auxiliaries of any kind. Said raw materials and auxiliaries include, in particular, oils, fats, waxes, film formers, preservatives and also auxiliaries which usually determine the application properties, such as thickeners and rheological additives, such as, for example, bentonite, hectorite, silicon dioxide, Ca silicates, gelatin, high molecular weight carbohydrates and / or surface active auxiliaries. Formulations comprising the effect pigments according to the invention may belong to the lipophilic, hydrophilic or hydrophobic type. In the case of heterogeneous formulations with separate aqueous and non-aqueous phases, the particles according to the invention may in each case be present in only one of the two phases or may be distributed in both phases. The pH value of the aqueous formulation may be from 1 to 14, preferably from 2 to 11, particularly preferably from 5 to 6. The concentration of the effect pigments according to the invention in the formulation is not limited. Depending on the application, the concentration may be from 0.001 (rinse-off products, e.g. shower gels) to 99% (e.g. gloss effect articles for specific applications). The effect pigments according to the invention can also be further combined with cosmetic active compounds. Suitable active compounds are, for example, insect repellents; UV A / BC protection filters (e.g. OMC, B3, MBC), anti-ageing active compounds, vitamins and their derivatives (e.g. vitamins A, C, E, etc.), tanning agents (e.g. DHA, erythrulose, in particular) and further cosmetic active compounds, for example bisabolol, LPO, ectoine, emblica, allantoin, bioflavonoids and their derivatives.

[0019] With regard to the use of effect pigments in paints and inks, all fields of application known to the skilled artisan are possible, such as powder coatings, automotive paints, inks for gravure printing, offset printing or flexographic printing inks, and inks for paints for outdoor applications. The paints and inks here can be radiation-curable, physically drying or chemically curable. For the preparation of printing inks or liquid paints, a large number of binders are suitable, for example those based on acrylates, methacrylates, polyesters, polyurethanes, nitrocellulose, ethylcellulose, polyamides, polyvinyl butyrates, phenolic resins, maleic resins, starch or polyvinyl alcohol, amino resins, alkyd resins, epoxy resins, polytetrafluoroethylene, polyvinylidene fluoride, polyvinyl chloride or mixtures thereof, especially water-soluble types. The paints can be powder coatings or water-based or solvent-based paints, where the choice of paint components is general knowledge of the skilled artisan. Typical polymeric binders for powder coatings are, for example, polyesters, epoxides, polyurethanes, acrylates or mixtures thereof.

[0020] Furthermore, the effect pigments according to the invention can be used in films and plastics, such as agricultural sheets, infrared reflecting films, infrared reflecting films and panels, gift films, plastic containers and moldings for all applications known to those skilled in the art. Suitable plastics are all plastics that are common for the incorporation of the effect pigments according to the invention, such as thermosetting plastics, elastomers or thermoplastics. A description of the possible applications and plastics, the processing methods and additives that can be used can be found, for example, in RD 472005 or R.Glausch, M.Kieser, R.Maisch, G.Pfaff, J.Weitzel, Perlglanzpigmente [Pearlescent Pigments], Curt R.Vincentz Verlag(1996), 83 ff., the disclosure of which is also incorporated herein by reference. Furthermore, the effect pigments according to the invention are suitable for use in security printing and security-related functions, for example for anti-counterfeit cards and identity documents, such as entrance tickets, identity documents, bank notes, cheques and check cards, and for other anti-counterfeit documents. In the agricultural field, the effect pigments can be used as seed coloring or other starting materials, in addition to for food coloring in the food field. The effect pigments according to the invention can also be used for the pigmentation of coatings in pharmaceuticals, such as, for example, tablets or dragees. The usually silver-grey effect pigments according to the invention with a metallic luster are, in contrast to aluminum pigments, transparent to electromagnetic radiation (20 MHz to 100 GHz) and are therefore particularly suitable also for painting radar sensors or the covers of radar sensors. Preferred finishes, in particular for the industrial and automotive sector and for agricultural machinery, comprise 1 to 40% by weight, in particular 10 to 25% by weight, of effect pigments according to the invention. In the automotive sector, the effect pigments according to the invention are suitable for both metal and plastic finishes, for example bumpers, radar sensors, radiator grilles, exterior mirrors, which is particularly important for automobiles to have a uniform appearance when painted.Furthermore, it is also possible to prepare paint formulations with the pigments according to the invention for coatings which can also be used in the automotive sector.

[0021] The effect pigments according to the invention can also be mixed in any ratio, for example with aluminum pigments, to achieve further color effects. Depending on the mixing ratio, the pigment mixture is still transparent to electromagnetic radiation. In the case of radar-transparent automotive finishes, the pigment mixture consisting of the effect pigments according to the invention and aluminum pigments contains 0.1 to 5% by weight or less, preferably 1 to 3% by weight or less of aluminum pigment. For laser marking with the effect pigments according to the invention, all known thermoplastics can be used, as described, for example, in Ullmann, Vol. 15, pp. 457 ff., Verlag VCH. Suitable plastics are, for example, polyethylene, polypropylene, polyamide, polyester, polyester-ester, polyether-ester, polyphenylene ether, polyacetal, polybutylene terephthalate, polymethyl acrylate, polyvinyl acetate, polystyrene, acrylonitrile-butadiene-styrene copolymer, acrylonitrile-styrene-acrylate copolymer, polycarbonate, polyethersulfone, polyetherketone, polyurethane, and also copolymers and / or mixtures thereof. The effect pigments according to the invention are therefore also suitable for incorporation into silicone rubber or silicone resin.

[0022] The effect pigments according to the invention are incorporated into thermoplastics by mixing plastic granules with the effect pigment and then shaping the mixture under the action of heat. Known adhesives, organic polymer-compatible solvents, stabilizers and / or surfactants that are temperature-stable under the operating conditions are all known to the skilled artisan and can be added to the plastic granules when incorporating the effect pigment. Colored plastic granules are generally prepared by first introducing the plastic granules into a suitable mixer, wetting the granules with any additives and then mixing in the effect pigment. The mixture thus obtained can then be directly processed in an extruder or injection moulding machine. Marking is then carried out using suitable radiation. In particular, the silicone rubbers are those vulcanized at relatively low temperatures (room temperature to <200°C, 2-component) (known as RTV2 silicones), those vulcanized at relatively high temperatures (approximately 110°C, 2-component or approximately 160°C, 1-component) (known as HTV silicones) or those vulcanized in the liquid state (approximately 110°C, 2-component) (known as LSR silicones). The effect pigments according to the invention are added to the abovementioned 1-component or 2-component silicone rubber components and homogeneously distributed therein. If necessary, the mixture is then introduced into the cavity of an injection mould and vulcanized under suitable conditions. The conditions necessary for this purpose, such as temperature, pressure and reaction time, are known to the skilled person and are selected depending on the starting materials and the desired final elastomer. In the case of 1-component systems, no separate addition of vulcanizing agents is necessary. The vulcanization process can be accelerated by the supply of actinic radiation, for example by UV or gamma radiation. The mixture thus obtained is removed from the injection moulding machine. Marking is then carried out using suitable radiation. Marking is preferably carried out using high-energy radiation, generally in the wavelength range of 157 to 10600 nm, in particular in the range of 300 to 10600 nm. Examples include CO2 lasers (10600 nm), Nd:YAG lasers (1064 or 532 nm) or pulsed UV lasers (excimer lasers). Excimer lasers have the following wavelengths: F2 excimer laser (157 nm), ArF excimer laser (193 nm), KrCl excimer laser (222 nm), KrF excimer laser (248 nm), XeCl excimer laser (308 nm), XeF excimer laser (351 nm), frequency-doubled Nd:YAG lasers with wavelengths of 355 nm (frequency tripled) or 265 nm (frequency quadrupled). Particular preference is given to the use of Nd:YAG lasers (1064 or 532 nm) and CO2 lasers. The energy density of the laser used is generally 0.3 mJ / cm 2 ~50J / cm 2 , preferably 0.3 mJ / cm 2 ~10J / cm 2 The range is.

[0023] Laser marking is carried out by introducing the sample into the beam path of a pulsed laser, preferably a CO2 or Nd:YAG laser. Furthermore, marking using an excimer laser, for example via mask technology, is possible. However, the desired result can also be achieved using other conventional lasers with a wavelength in the high absorption region of the laser light absorbing material used. The marking obtained is determined by the irradiation time of the laser (or the number of pulses in the case of a pulsed laser) and the irradiation power of the laser, as well as the plastic or paint system used. The power of the laser used depends on the concrete application and can be easily determined by the skilled person in each individual case. When a pulsed laser is used, the pulse frequency is generally in the range of 1 to 30 kHz. Corresponding lasers that can be used in the method according to the invention are commercially available. The use of the effect pigments according to the invention for laser marking can be carried out in all the abovementioned plastics. The plastics thus colored can be used as mouldings in the electrical, electronics and automotive industries. Further important fields of application for laser inscription are ID cards and plastic tags for the identification of animals. In the case of laser marking in the abovementioned applications, the proportion of the effect pigment in the plastic is 0.01-10% by weight, preferably 0.05-5% by weight, in particular 0.1-3% by weight. The labelling and inscription of housings, cables, key caps, trims or functional parts in the heating, exhaust and cooling sectors or of switches, plugs, levers and handles made of plastics coloured with the pigments according to the invention can be marked with the aid of a laser beam, even in areas that are difficult to access. The markings are distinguished by the fact that they are wipe-resistant and scratch-resistant, are stable during the subsequent sterilisation process and can be applied in a hygienically clean manner in the marking process.

[0024] Needless to say, for various applications the effect pigments according to the invention can also be used advantageously in mixtures with, for example, the following pigments: metallic effect pigments, for example based on iron or aluminum flakes; - pearlescent pigments based on metal oxide-coated synthetic mica flakes, natural mica flakes, glass flakes, Al2O3 flakes, Fe2O3 flakes or SiO2 flakes; -Absorbing pigments; - goniochromatic pigments; - multi-layer pigments (preferably 2, 3, 4, 5 or 7 layers) based on metal oxide-coated synthetic mica flakes, natural mica flakes, glass flakes, Al2O3 flakes, Fe2O3 flakes or SiO2 flakes; -Organic dyes; - organic pigments; - inorganic pigments, such as, for example, transparent and opaque white, colored and black pigments; in particular, temperature-stable ceramic pigments; -Flake iron oxide; -Carbon black; -Ceramic color body; - Functional pigments, e.g. IR reflective or conductive pigments.

[0025] The effect pigments according to the invention can be mixed in any ratio with standard commercial pigments and / or further standard commercial fillers. Fillers that may be mentioned include, for example, natural and synthetic mica, nylon powder, pure or filled melamine resin, talc, glass, kaolin, oxides or hydroxides of aluminum, magnesium, calcium, zinc, BiOCl, barium sulfate, calcium sulfate, calcium carbonate, magnesium carbonate, carbon, and physical or chemical combinations of these substances. There are no restrictions regarding the particle shape of the filler. The shape may be, for example, flake-like, spherical or acicular, depending on the requirements. Formulations comprising the effect pigments according to the invention may furthermore comprise at least one component selected from the group: absorbents, astringents, antimicrobial substances, antioxidants, antifoaming agents, antistatic agents, binders, biological additives, bleaching agents, chelating agents, deodorizing agents, emollients, emulsifiers, emulsion stabilizers, dyes, wetting agents, film-formers, fillers, fragrances, flavorings, insect repellents, preservatives, preservatives, cosmetic oils, solvents, oxidizing agents, botanical ingredients, buffer substances, reducing agents, surfactants, propellant gases, opacifying agents, UV filters, UV absorbers, modifiers, viscosity regulators, fragrances, vitamins, enzymes, trace elements, proteins, carbohydrates, organic pigments, inorganic pigments such as, for example, TiO2, carbon black, further effect pigments, metallic pigments such as, for example, aluminium pigments, effect pigments, metal-effect pigments. The effect pigments according to the invention are furthermore suitable for the preparation of flowable pigment preparations and dry preparations comprising one or more particles according to the invention, a binder and optionally one or more additives. Dry preparations are also taken to mean preparations comprising 0-8% by weight, preferably 2-8% by weight, in particular 3-6% by weight, of water and / or a solvent or solvent mixture. The dry preparations are preferably in the form of pellets, granules, chips, sausages or briquettes and have a particle size of 0.2-80 mm. The dry preparations are used in particular for the preparation of printing inks and cosmetic formulations.

[0026] The entire disclosures of all patent applications, patents and publications cited above are hereby incorporated by reference. The following examples are intended to illustrate the invention in detail but without limiting it. EXAMPLES

[0027] Example 1: Comparative Example (without F doping): Example 1a 30 g of Iriodin® 119 (TiO2-coated mica flakes with a particle size distribution of 5-25 μm, Merck KGaA) are carefully mixed with 0.34 g of Si powder (<100 μm; Merck KGaA), 0.23 g of CaCl2 fine powder (<20 μm, Merck KGaA) and 0.45 g of talc (<15 μm, Mondo) in a PP container in a Hauschild DAC 150 FVZ Speedmixer. The mixture is distributed homogeneously in a quartz boat. The boat is placed in a quartz tube (inner diameter 5 cm, length 100 cm) equipped with gas supply lines (ground joint-olive adapters) on both sides. Nitrogen is blown into the reaction space at 55 L / h (1.75 bar) from one inlet and fed to an exhaust at the other end through a pair of wash bottles connected so that the liquid cannot rise back into the oven. After 15 minutes, the quartz tube is placed in a tubular oven with the boat in the center of the heating zone (adjusted to a temperature of 850° C.) and left there for 45 minutes. The quartz tube is then removed from the oven and cooled under a nitrogen flow for 30 minutes. The calcined powder is sieved through a 40 μm sieve. A silver-white effect pigment is obtained which does not exhibit a metallic luster. X-ray diffractograms before and after calcination show that the crystallographic structure of the TiO2-layer on the mica flakes is not changed by reductive calcination: the crystallographic structure of the TiO2-layer is unchanged, i.e., no titanium suboxide is present. Example 1b As in Example 1a, but the temperature was increased from 850°C to 900°C. Example 1c As in Example 1a, but the temperature was increased from 850°C to 950°C. [Table 1] The effect pigments of Examples 1a, 1b and 1c all show no or only little hiding power, and the metallic luster is only evident above 950° C. However, at the same time at higher temperatures the formation of undesirable aggregates is observed.

[0028] Example 2: Fluoride doping from various precursors Example 2a: Doping with CaF2 30 g of Iriodin® 119 (TiO2-coated mica flakes with particle size distribution of 5-25 μm, Merck KGaA), 0.34 g of Si powder (<100 μm; Merck KGaA), 0.23 g of CaCl2 powder (<20 μm; Merck KGaA) are carefully mixed with 0.45 g of talc (<15 μm, Mondo) and 0.1 g of CaF2 powder (<20 μm, Merck KGaA) in a PP container in a Hauschild DAC 150 FVZ Speedmixer. Experiments with MgF2 powder (Merck KGaA), NaF powder (Aldrich) and PTFE powder (35 μm, Aldrich) instead of CaF2 can also be performed. If fluoride-containing mica (fluorphlogopite, Merck KGaA) is used, the addition of talc can be omitted. The respective amounts are given in Table 2. The mixture is distributed homogeneously in the quartz boat. The boat is placed in a quartz tube (5 cm internal diameter, 100 cm long) equipped with gas supply lines (ground joint-olive adapter) on both sides. Nitrogen is blown into the reaction space at 55 L / h (1.75 bar) from one inlet and fed to the exhaust at the other end through a pair of wash bottles connected so that the liquid cannot rise back into the oven. After 15 minutes, the quartz tube is placed in a tubular oven so that the boat is in the center of the heating zone (adjusted to a temperature of 850 ° C or 875 ° C) and left there for 45 minutes. The quartz tube is then removed from the oven and cooled under a nitrogen flow for 30 minutes. The calcined powder is sieved through a 40 μm sieve. Example 2b: Doping with MgF2 As in Example 2a, but with 0.1 g MgF2 (Merck KGaA) instead of 0.1 g CaF2. Example 2c: Doping with NaF As in Example 2a, but 0.1 g of NaF (Aldrich) is used instead of 0.1 g of CaF2. Example 2d: Doping with PTFE powder As in Example 2a, but 0.1 g of polytetrafluoroethylene powder (35 μm, Aldrich) is used instead of 0.1 g of CaF 2 . Example 2e: Doping with Fluorphlogopite 30 g of Iriodin® 119 (TiO2-coated mica flakes with a particle size distribution of 5-25 μm, Merck KGaA), 0.34 g of Si powder (<100 μm; Merck KGaA), 0.23 g of CaCl2 fine powder (<20 μm; Merck KGaA) and 0.45 g of fluorphlogopite (particle size <15 μm, Merck KGaA) are carefully mixed in a PP container in a Hauschild DAC 150 FVZ Speedmixer. The respective amounts are listed in Table 2. The mixture is distributed homogeneously in a quartz boat. The boat is placed in a quartz tube (inner diameter 5 cm, length 100 cm) equipped with gas supply lines (ground joint-olive adapter) on both sides. Nitrogen is blown into the reaction space at 55 L / h (1.75 bar) through one inlet and through a pair of wash bottles connected so that the liquid cannot rise back into the oven, to an exhaust at the other end. After 15 minutes, the quartz tube is placed in a tube oven so that the boat is in the center of the heating zone (regulated to a temperature of 850° C. or 875° C.) and left there for 45 minutes. The quartz tube is then removed from the oven and cooled under a nitrogen flow for 30 minutes. The calcined powder is sieved through a 40 μm sieve.

[0029] The pigments of Examples 2a-e show a silver-grey metallic luster and, with the exception of Example 2c, show a hiding power significantly higher than Comparative Examples 1a-c prepared at the same temperature. With this pigment, even at 850 °C a hiding power is obtained that the Comparative Examples do not reach at 950 °C, but a significant aggregate formation is already observed. The pigment of Example 2d is significantly darker in appearance than the pigments of Examples 2a-c and 22. It is thus also possible to control the brightness of the pigment without loss of quality (aggregate formation) to the extent that could not be achieved with the approach selected for Comparative Examples 1a-c. [Table 2]

[0030] Example 3: Temperature variation using fluorphlogopite 30 g of Iriodin® 119 (TiO2-coated mica flakes with a particle size distribution of 5-25 μm, Merck KGaA) are carefully mixed with 0.79 g of Si powder (<100 μm; Merck KGaA), 0.69 g of CaCl2 powder (<20 μm; Merck KGaA) and 1.35 g of ground fluorphlogopite (<15 μm, Merck KGaA) in a PP container in a Hauschild DAC 150 FVZ Speedmixer. The mixture is distributed homogeneously in a quartz boat. The boat is placed in a quartz tube (inner diameter 5 cm, length 100 cm) equipped with gas supply lines (ground joint-olive adapters) on both sides. Nitrogen is blown into the reaction space at 55 L / h (1.75 bar) from one inlet and fed to an exhaust at the other end through a pair of wash bottles connected so that the liquid cannot rise back into the oven. After 15 minutes, the quartz tube is placed in a tubular oven so that the boat is in the center of the heating zone (regulated at a temperature of 850° C.) and left there for 45 minutes. The quartz tube is then removed from the oven and cooled under a nitrogen flow for 30 minutes. The calcined powder is sieved through a 40 μm sieve. Example 3b Example 3a is repeated but at a temperature of 875°C. Example 3c Example 3a is repeated but at a temperature of 900°C. Example 3d Example 3a is repeated but at a temperature of 925°C. [Table 3] Example 3 shows the influence of temperature on the optical properties, in particular the metallic luster: at temperatures > 900°C the metallic luster is lost and a matt silver-grey effect pigment is obtained.

[0031] Example 4 As summarized in Table 4, variations are carried out using various proportions of silicon, calcium chloride, and fluorphlogopite as in Examples 2e and 3a, but under otherwise identical reaction conditions and with the same workup. [Table 4] Examples 4a-4f each give a silver-grey effect pigment with metallic luster and high hiding power. The pigments are very close in value but differ in blueness. In contrast, the pigments prepared according to Comparative Examples 1a-c show yellowish to torinoko hues. Cool, intense blue hues are expected for metallic effect pigments.

[0032] Example 5: Effect pigments with different TiO2 layer thicknesses Example 5a 30 g of Iriodin® 211 Fine Red (TiO2-coated mica flakes with white masstone and red reflections and a particle size distribution of 5-25 μm, Merck KGaA), 0.26 g of Si powder (<100 μm; Merck KGaA), 0.46 g of CaCl2 powder (<20 μm; Merck KGaA) and 0.45 g of ground fluorphlogopite (<15 μm, Merck KGaA) are carefully ground in a PP container in a Hauschild DAC 150 FVZ Speedmixer. The mixture is distributed homogeneously in a quartz boat. The boat is placed in a quartz tube (inner diameter 5 cm, length 100 cm) equipped with gas supply lines (ground joint-olive adapter) on both sides. Nitrogen is blown into the reaction space at 55 L / h (1.75 bar) through one inlet and through a pair of wash bottles connected so that the liquid cannot rise back into the oven, to an exhaust at the other end. After 15 minutes, the quartz tube is placed in a tube oven so that the boat is in the center of the heating zone (regulated at a temperature of 925° C.) and left there for 15 minutes. The quartz tube is then removed from the oven and cooled under a nitrogen flow for 30 minutes. The calcined powder is sieved through a 40 μm sieve. The pale green interference pigment gives a blue-green effect pigment with grey absorption and high hiding power. Example 5b 30 g of Iriodin® 231 Fine Green (TiO2-coated mica flakes with white masstone and green reflection and particle size distribution of 5-25 μm, Merck KGaA), 0.26 g of Si powder (<100 μm; Merck KGaA), 0.46 g of CaCl2 powder (<20 μm; Merck KGaA) and 0.45 g of ground fluorphlogopite (<15 μm, Merck KGaA) are carefully ground in a PP container in a Hauschild DAC 150 FVZ Speedmixer. The mixture is distributed homogeneously in a quartz boat. The boat is placed in a quartz tube (inner diameter 5 cm, length 100 cm) equipped with gas supply lines (ground joint-olive adapter) on both sides. Nitrogen is blown into the reaction space at 55 L / h (1.75 bar) through one inlet and through a pair of wash bottles connected so that the liquid cannot rise back into the oven, to an exhaust at the other end. After 15 minutes, the quartz tube is placed in a tube oven so that the boat is in the center of the heating zone (regulated at a temperature of 925° C.) and left there for 15 minutes. The quartz tube is then removed from the oven and cooled under a nitrogen flow for 30 minutes. The calcined powder is sieved through a 40 μm sieve. A copper-coloured effect pigment is obtained which has grey absorption and high hiding power. [Table 5]

[0033] Example 6 Example 6a 30 g of Colorstream® T10-02 Arctic Fire (TiO2-coated SiO2 flakes with a particle size distribution of 5-60 μm, Merck KGaA) are vigorously mixed with 0.26 g of Si powder (<100 μm; Merck KGaA), 0.46 g of CaCl2 powder (<20 μm; Merck KGaA) and 0.45 g of ground fluorphlogopite (<15 μm, Merck KGaA). The mixture is distributed homogeneously in a quartz boat. The boat is placed in a quartz tube (inner diameter 5 cm, length 100 cm) equipped with gas supply lines (ground joint-olive adapters) on both sides. Nitrogen is blown into the reaction space at 55 L / h (1.75 bar) from one inlet and fed to an exhaust at the other end through a pair of wash bottles connected so that the liquid cannot rise back into the oven. After 15 minutes, the quartz tube is placed in a tubular oven so that the boat is in the center of the heating zone (regulated at a temperature of 925° C.) and left there for 30 minutes. The quartz tube is then removed from the oven and cooled under a nitrogen flow for 30 minutes. The calcined powder is sieved through a 63 μm sieve. The effect pigments thus obtained exhibit an intense lilac to pale green color flop and a metallic luster. Example 6b Additionally, darker variants are prepared using larger amounts of reactants as shown in the following table. At higher reactant ratios, the effect pigments become significantly darker in appearance. Color flop is less pronounced. [Table 6]

[0034] Example 7: Example using glass flakes as substrate Example 7a 30 g of Miraval® 5311 Scenic White (TiO2-coated glass flakes with white masstone and particle size distribution of 10-100 μm, Merck KGaA) are carefully mixed with 0.79 g of Si powder (particle size <100 μm; Merck KGaA), 0.69 g of CaCl2 powder (<20 μm; Merck KGaA) and 1.35 g of ground fluorphlogopite (<15 μm, Merck KGaA) in a PP container in a Hauschild DAC 150 FVZ Speedmixer. The mixture is distributed homogeneously in a quartz boat. The boat is placed in a quartz tube (inner diameter 5 cm, length 100 cm) equipped with gas supply lines (ground joint-olive adapter) on both sides. Nitrogen is blown into the reaction space at 55 L / h (1.75 bar) through one inlet and through a pair of wash bottles connected so that the liquid cannot rise back into the oven, to an exhaust at the other end. After 15 minutes, the quartz tube is placed in a tube oven so that the boat is in the center of the heating zone (regulated at a temperature of 700° C.) and left there for 45 minutes. The quartz tube is then removed from the oven and cooled under a nitrogen flow for 30 minutes. The calcined powder is sieved through a 100 μm sieve. Example 7b 30 g of Miraval® 5402 Pacific Twinkle (TiO2-coated glass flakes with a white masstone and a particle size distribution of 10-100 μm, Merck KGaA), 0.79 g of Si powder (<100 μm; Merck KGaA), 0.69 g of CaCl2 powder (<20 μm; Merck KGaA) and 1.35 g of ground fluorphlogopite (<15 μm, Merck KGaA) were added to a Hauschild DAC 150 FVZ. Carefully mix in a PP container in a Speedmixer. The mixture is distributed evenly in the quartz boat. The boat is placed in a quartz tube (5 cm internal diameter, 100 cm long) equipped with gas supply lines (ground joint-olive adapter) on both sides. Nitrogen is blown into the reaction space at 55 L / h (1.75 bar) from one inlet and fed to an exhaust at the other end through a pair of wash bottles connected so that the liquid cannot rise back into the oven. After 15 minutes, the quartz tube is placed in a tubular oven so that the boat is in the center of the heating zone (regulated at a temperature of 700° C.) and left there for 45 minutes. The quartz tube is then removed from the oven and cooled under a nitrogen flow for 30 minutes. The calcined powder is sieved through a 100 μm sieve. The effect pigments of Examples 7a and 7b are dark in appearance compared to the base pigment; the silver pigment of Example 7a has discernible metallic properties and the turquoise interference pigment of Example 7b results in a strong blue effect pigment, but in both examples calcination is only carried out at 700° C. to avoid destruction of the temperature-sensitive glass flakes. [Table 7]

[0035] Example 8: Example using synthetic mica as substrate Example 8a 30 g of Iriodin® 6123 (TiO2-coated synthetic mica flakes (= fluorophlogopite) with a particle size distribution of 5-25 μm, Merck KGaA) are carefully mixed with 0.34 g of Si powder (<100 μm; Merck KGaA), 0.23 g of CaCl2 powder (<20 μm, Merck KGaA) and 0.45 g of talc (<15 μm, Mondo) in a PP container in a Hauschild DAC 150 FVZ Speedmixer. Due to the fluorine-containing substrate (synthetic mica), further addition of fluoride precursors is omitted. The mixture is distributed homogeneously in a quartz boat. The boat is placed in a quartz tube (inner diameter 5 cm, length 100 cm) equipped with gas supply lines (ground joint-olive adapters) on both sides of it. Nitrogen is blown into the reaction space at 55 L / h (1.75 bar) through one inlet and through a pair of wash bottles connected so that the liquid cannot rise back into the oven, to an exhaust at the other end. After 15 minutes, the quartz tube is placed in a tube oven so that the boat is in the center of the heating zone (regulated at a temperature of 850° C.) and left there for 45 minutes. The quartz tube is then removed from the oven and cooled under a nitrogen flow for 30 minutes. The calcined powder is sieved through a 40 μm sieve. Example 8b Example 8a is repeated using reduced reactants as shown in Table 8. The substrate containing synthetic mica (=fluorophlogopite) itself contains sufficient fluoride ions, so that the addition of additional fluoride precursors is not necessary. The pigment of Example 8a is much darker than, for example, a physical mixture with pure fluorophlogopite, due to the presence of a fluoride source inside the reduced pigment. Thus, Example 8b, which uses a significant reduction in the use of reactants, gives a pigment close in brightness and hiding power to the pigment of Example 4. [Table 8]

[0036] Example 9: Example using Al2O3 flakes as substrate Example 9a 30 g of Xirallic® Crystal Silver T50-10 (TiO2-coated aluminum oxide flakes with white masstone and silver-white reflection and particle size distribution of 15-22 μm, Merck KGaA), 0.34 g of Si powder (<100 μm; Merck KGaA), 0.23 g of CaCl2 powder (<20 μm; Merck KGaA) are carefully mixed with 0.45 g of talc (<15 μm, Mondo) and 0.1 g of CaF2 powder (<20 μm, Merck KGaA) in a PP container in a Hauschild DAC 150 FVZ Speedmixer. Experiments are carried out using MgF2 (<20 μm, Merck KGaA) and fluorphlogopite (<15 μm, synthetic mica, Merck KGaA) instead of CaF2. When fluorphlogopite is used, the addition of talc is omitted, since the phyllosilicates improve the fluidity of the mixture like talc. The respective amounts are given in the following tables (9a-c). The mixture is distributed evenly in the quartz boat. The boat is placed in a quartz tube (5 cm inner diameter, 100 cm long) equipped with gas supply lines (ground joint-olive adapter) on both sides. Nitrogen is blown into the reaction space at 55 L / h (1.75 bar) from one inlet and fed to the exhaust at the other end through a pair of washing bottles connected so that the liquid cannot rise back into the oven. After 15 minutes, the quartz tube is placed in a tubular oven so that the boat is in the center of the heating zone (adjusted to a temperature of 850 °C) and left there for 45 minutes. The quartz tube is then removed from the oven and cooled under a nitrogen flow for 30 minutes. The calcined powder is sieved through a 40 μm sieve. The effect pigments of Examples 9a-c have a dark metallic grey hue and show the typical sparkle effect when using aluminium oxide as substrate, whereas in Examples 9a and 9b a blue hue is evident.

[0037] In a variant, 10 g of Xirallic® Crystal Silver T50-10 (TiO2-coated aluminum oxide flakes with white masstone and silver-white reflection and particle size distribution of 15-22 μm, Merck KGaA), 0.11 g of Si powder (<100 μm; Merck KGaA), 0.08 g of CaCl2 powder (<20 μm; Merck KGaA) are carefully mixed in a PP container in a Hauschild DAC 150 FVZ Speedmixer and distributed in a uniform pile in the center of the quartz boat. 0.2 g of CaF2 powder (<20 μm, Merck KGaA) are piled along the mixture on both the left and right sides of the quartz boat, approximately 2 cm apart. The respective amounts are listed in the table below (Example 9e). In a control experiment (Example 9d), no CaF2 is placed along the mixture. The boat is placed in a quartz tube (5 cm internal diameter, 100 cm long) equipped with gas supply lines (ground joint-olive adapter) on both sides. Nitrogen is blown into the reaction space at 55 L / h (1.75 bar) from one inlet and fed to an exhaust outlet at the other end through a pair of wash bottles connected so that the liquid cannot rise back into the oven. After 15 minutes, the quartz tube is placed in a tubular oven so that the boat is in the center of the heating zone (regulated at a temperature of 850° C.) and left there for 30 minutes. The quartz tube is then removed from the oven and cooled under a nitrogen flow for 30 minutes. Samples of the mixture of untreated pigments from Examples 9d and 9e, the control experiment (without CaF2) and the experiment with CaF2 adjacent to the reaction mixture are taken, washed with distilled water and dried at 110°C. The samples thus prepared are subjected to X-ray photoelectron spectroscopy (XPS) to determine the Ti in the TiO2 crystal lattice. 3+ and F - Reveal the status of. [Table 9] Quantitative fluoride determination by combustion ion chromatography gives values ​​of 540-935 μg fluoride per gram of sample (corresponding to 0.003-0.005 at% fluoride).

[0038] Example 10: Nb-doped titanium oxide on mica flakes 30 g of TiO2-coated mica flakes (titanium oxide already doped with 8 mol% niobium during synthesis by co-deposition of the corresponding TiCl4 and NbCl5 in a mixed solution of HCl and deionized water) with a white masstone and bluish reflection in air at 700 °C and a particle size distribution of 10-60 μm are carefully mixed with 0.26 g of Si powder (<100 μm; Merck KGaA), 0.34 g of CaCl2 powder (<20 μm; Merck KGaA) and 0.45 g of fluorphlogopite (<15 μm, synthetic mica, Merck KGaA) in a PP container in a Hauschild DAC 150 FVZ Speedmixer. The mixture is distributed homogeneously in a quartz boat. The boat is placed in a quartz tube (inner diameter 5 cm, length 100 cm) equipped with gas supply lines (ground joint-olive adapter) on both sides of it. Nitrogen is blown into the reaction space at 55 L / h (1.75 bar) through one inlet and through a pair of wash bottles connected so that the liquid cannot rise back into the oven, to an exhaust at the other end. After 15 minutes, the quartz tube is placed in a tube oven so that the boat is in the center of the heating zone (regulated at a temperature of 850° C.) and left there for 45 minutes. The quartz tube is then removed from the oven and cooled under a nitrogen flow for 30 minutes. The calcined powder is sieved through a 40 μm sieve. For comparison, a sample of Nb-doped TiO2 pigment dried at 110°C for 18 hours after precipitation is calcined in air at 850°C for 45 minutes. This calcined powder is likewise sieved through a 40 μm sieve. [Table 10]

[0039] Example 11: Post-treatment with sodium hydroxide solution 250 g of the effect pigment corresponding to Example 2a are suspended in about 2000 mL of deionized water (10-15% by weight) and warmed to 70° C. with stirring at 900 rpm. The pH is brought to 11.0 over 60 min using 32% sodium hydroxide solution. The pH is not kept constant but is continually readjusted over the next 8 h by metered addition of 32% sodium hydroxide solution. The suspension is filtered while still warm and the filter is rinsed with deionized water until the conductivity of the filtrate is below 200 μS / cm. At this point the material may be dried at 90° C. for 16 hours or used directly as an aqueous suspension for post-coating (see Example 13). The product will not change in color, but will be significantly finer and easier to sieve. A more uniform distribution of pigment will be evident on the paint card. The granularity of pigmented coating applications can be evaluated using the mac i multi-angle color effect measuring device from BYK Instruments (byk-instruments.com). For this, in said device, a CCD chip is used to generate images under diffuse illumination and the corresponding light / dark distribution is evaluated. A smaller granularity value represents a more uniform surface. Granularity values ​​of ≦2.5 frequently prove to be advantageous in said applications. The granularity factor generally correlates very well with optical and microscopic observations. [Table 11]

[0040] Example 12: Physical Properties / Radar Transmittance 30 g of Iriodin® 119 (TiO2-coated mica flakes with a particle size distribution of 5-25 μm, Merck KGaA) or the same amount of 30 g of Xirallic® Crystal Silver T50-10 (TiO2-coated aluminum oxide flakes with a white masstone and silver-white reflection and a particle size distribution of 15-22 μm, Merck KGaA), 0.34 g of Si powder (<100 μm; Merck KGaA), 0.23 g of CaCl2 powder (<20 μm; Merck KGaA), 0.45 g of talc (<15 μm, Mondo) and 0.1 g of CaF2 powder (<20 μm, Merck KGaA) are carefully mixed in a PP container in a Hauschild DAC 150 FVZ Speedmixer. The respective amounts are listed in Table 11. The mixture is uniformly distributed in a quartz boat. The boat is placed in a quartz tube (5 cm internal diameter, 100 cm long) equipped with gas supply lines on both sides (ground joint-olive adapter). Nitrogen is blown into the reaction space at 55 L / h (1.75 bar) through one inlet and fed to an exhaust at the other end through a pair of wash bottles connected so that the liquid cannot rise back into the oven. After 15 minutes, the quartz tube is placed in a tubular oven so that the boat is in the center of the heating zone (adjusted to a temperature of 850° C. or 875° C.) and left there for 45 minutes. The quartz tube is then removed from the oven and cooled under a nitrogen flow for 30 minutes. The calcined powder is sieved through a 40 μm sieve.

[0041] To be able to evaluate the radar transparency of the paint layer, a paint is prepared with 533.42 g of WBC 000 (binder) from MIPA and 16.17 g of pigment (18% PMC) and applied in three coats by air pressure application to a 350 μm thick Hostaphan RN 350 PET film (A4 size) from Mitsubishi Polyester Film GmbH. The layer thicknesses of the films thus produced are given in Table 12. As a reference, both an uncoated PET film (Example 12h) and a film coated with aluminum pigment (a 1:1 mixture of Stapa® IL Hydrolan 2156 and Stapa® IL Hydrolan 8154 (Eckar)) are prepared and measured with the same formulation as above (18% PMC). Measurements of the dielectric constant of the coating and the one-way transmission attenuation of the coating on the substrate were performed using a Perisens GmbH model RMS-D-77 / 79G instrument in standard mode. Table 12 shows the dielectric constant (permittivity) and one-way transmission attenuation of radar signals (dB) for a layer structure consisting of a PET film and an applied paint layer, where only one pass of the radar beam is considered. The powder resistivity is measured by compressing the sample in a cylindrical, electrically insulating plastic measuring cell between two electrically connected rams using a 10 kg weight. After compression, the cell is filled so that a sample height of approximately 1 cm is obtained in the measuring cell. The height h in cm is determined from the scale on the ram. The sample bottom area is given by the dimensions of the ram, which has a diameter d = 2 cm. The resistance R is measured at a voltage of 1 V using a Fluke 287 True RMS Multimeter measuring instrument. This allows the specific powder resistivity ρ S Calculate. ρ S = R × π × (d / 2) 2 / time [Table 12] [Table 13] All the examples show that the radar signal attenuation when using mica or aluminum oxide based pigments (Examples 12a-g) is clearly reduced compared to the aluminum pigment (Comparative Example 12i). If the degree of attenuation in level, power or field is quoted in the usual decibel (dB) units, the aluminum pigmentation (Example 12i) gives a value of 3.73 dB, which represents a loss of more than 57% of the initial power of the radar beam in one pass. The pigments according to the invention (Examples 12a-g), in contrast, have an attenuation of 1.20-1.30, which represents a loss of less than 26% of the initial power in one pass. However, the PET support film already has a proportion of 21.5% and its one-way attenuation is 1.05. Thus, pigmentation with pigments according to the invention contributes significantly to the realization of radar-compatible paint formulations.

[0042] Example 13: After Coating 150 g of the effect pigment of Example 2a are suspended in 1350 mL of deionized water at room temperature with stirring at 700 rpm (=10% pigment suspension). The temperature of the batch is adjusted to 75° C. (45 min). After the pigment is suspended, a pH of 6.8 is established using sulfuric acid (5%) and the mixture is stirred for a further 15 minutes. If necessary, the pH is corrected using NaOH or H2SO4. An aluminum chloride solution of 6.8 g AlCl3·6H2O (Merck KGaA) in 60 g deionized water is metered in at a uniform rate using an Ismatec hose pump during 120 min at 75 °C. During this addition, the pH is kept constant at 6.8 using sodium hydroxide solution (5%). The pH is kept at 6.80 for the following 10 min stirring period. The pH is slowly (5 min) adjusted to pH 6.3 using a small amount of H2SO4 (5%). The pH is kept at 6.3 for the next 5 min stirring period. Sodium water glass solution diluted from 8.4 g of 27% sodium water glass solution (Merck KGaA) and 60 g of deionized water are metered in at a uniform rate using an Ismatec hose pump over 120 minutes. The pH is kept constant at 6.3 during this addition using sulfuric acid (5%). The pH is kept at 6.30 for the following 20 minutes of stirring. The pH is slowly adjusted to pH 8.0 using small amounts of NaOH (5%). The pH is kept at 8.0 for the next 5 minutes of stirring. A mixture of 3.0 g of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane (ABCR; AB111130) and 3.0 g of 3-isocyanatopropyltriethoxysilane (ABCR; 111201) is added at a constant rate using a dropping funnel over a period of 60 min at 75 °C with stirring (700 rpm). A constant pH of 8.0 is maintained by metered addition of 5% sodium hydroxide solution. No pH adjustment is made during the following 45 min of stirring. The heating and the stirrer are switched off. The sample is allowed to settle. The suspension is drained directly onto a suction filter, filtered and washed in portions with 6×1 L of cold deionized water until the conductivity falls below a value of 30 μS / cm. Finally, the product is sucked dry. The pigment is then dried in a small layer thickness (3-4 cm) in a porcelain dish in a fan-assisted dryer preheated to 150° C. for 16 hours. The dry product is passed through a Retsch sieve, mesh width 40 μm, in portions. The yield is 154 g of post-coated product. The product is free of color change, but is flowable. A paint card reveals a more uniform distribution of the pigment. Subsequently, in weathering tests (SAEJ 2527) in paint systems from paint manufacturers PPG and Axalta, the material obtained in Example 2 shows good stability with only slight shifts in chroma and hiding power after 2000 and 4000 hours.

[0043] Paint card creation / color measurement To allow colorimetric evaluation of the pigments described according to the present invention, 0.9 g of each pigment sample is incorporated into 53.6 g of nitrocellulose / acrylic resin paint and homogenized using a Speedmixer (Hauschild, 2 min, 2800 rpm) to eliminate air bubbles. The pigment / paint mixture is applied to a black / white card with a wet film thickness of 500 μm using a paint tool. The cards are measured using a multi-angle spectrophotometer (Byk Mac-i from Byk-Gardner), where the following values ​​are tabulated: · Values ​​of L x 15°b, a x 15°b, b x 15°b for the lightness, red-green and blue-yellow hues of the paint preparations (CIELAB colour space according to EN ISO 11664-4); values ​​(b) measured on a black card at a reflection angle of 15° are given here. The less obvious the difference between the black and white backgrounds on the paint card, the more opaque the pigment. ΔE(75°)=((L×75°bL×75°w)^2+(a×75°ba×75°w)^2+(b×75°bb×75°w)^2)^0.5; color separation as an index of hiding power measured on a corresponding portion of the paint preparation at 75° back from the reflected angle, on a black / white card (b=black, w=white). Color separation ΔE(75°)

number

[0044] Quantitative measurement of F: Sample preparation / measurement: In each case, approximately 2 mg (6x quantitative) of sample is weighed into a quartz boat with a sacrificial vial and combusted in a stream of oxygen using CIC (combustion ion chromatography) at an oven temperature of 1050° C. The gases are collected in an absorption solution (H2O2 solution), oxidized, and the anions are measured using IC. Quantitative determination of fluoride by combustion ion chromatography gives values ​​of 550-950 μg fluoride per gram of sample (corresponding to 0.003-0.005 at% fluoride). [Table 16]

[0045] Usage example (UE) Example UE1: Automotive paint The pigment of Example 12 is blended into MIPA WBC 000 base paint (MIPA SE). Depending on the target shade, a certain amount of pigment is used. To produce a full tone, 2% by weight of the above pigment of Example 12 is utilized in the formulation. 1000s are obtained by diluting with distilled water. -1It may become evident that the paint needs to be adjusted to a spray viscosity of 70-75 mPa·s at 20°C. The pigmented base paint is applied by spray coating to a Leneta black / white T21G metal panel. For this purpose, an automatic Oerter APL 4.6 spray applicator with a DeVilbiss AGMD2616 spray gun (1.4 mm nozzle, 767c cap) is used. The spray pressure is 4200 mbar, the material flow rate is about 110 mL / min and the distance between the spray gun and the substrate is about 30 cm. The spray gun moves at 0.45 m / s and three layers are applied at intervals of 30 seconds. The resulting dry film thickness is 10-20 μm, preferably 11-15 μm. After pre-drying the pigmented layer by air circulation at room temperature, a clear coat is applied on top of this substrate and baked for complete coverage. The panels have a pale silver-grey appearance and exhibit excellent hiding power and strong light-dark effects on slope. Example UE2: Solvent-based gravure printing on cardboard 90 g of the pigment of Example 12 is mixed with 200 g of Siegwerk NC TOB OPV 00 binder in an Engelsmann RRM Mini-II tumble mixer for 5 minutes. The mixture is then homogenized with at least 125 g of a solvent mixture containing ethanol and ethyl acetate 2:1 (V / V) using a Visco-Jet stirrer at 1200 rpm in order to adjust the viscosity. The same solvent mixture is filled up to 200 g in a DIN4 flow cup and the viscosity is adjusted so that the flow time is 17 seconds (23°C). The printing ink thus prepared is used on a standard commercial printing press equipped with an electrochemically imprinted gravure cylinder with 70 lines / cm, intercell channels and transverse cells. Suitable substrates are both films, coated paper and covered cardboard. The result is a uniformly opaque printed image with sharp edges in pale silver-grey with a metallic appearance, even on black cardboard. Example UE3: Plastic granules for injection molding 494 g of Purell GA 776 polyethylene (PE-HD) granules from Lyondell Basell are mixed with 1 g of Process Aid-24 (adhesion promoter) from ColorMatrix in an Engelsmann RRM Mini-II tumbler mixer for 5 minutes, then 5 g of the pigment of Example 12 are added and mixing is continued for another 5 minutes. The dry mixture thus prepared is used for injection molding of plastic sample tiles with dimensions of 9 x 6 x 0.1 cm. The samples show the uniform metallic silver luster of the example pigment.

[0046] Example UE4: Lipstick [Table 17] The ingredients of phase B are heated to 75°C and melted. The pigment of Example 4b (phase A) is added and everything is mixed well by stirring. The lipstick material is then stirred with the fragrance of phase C in a molding apparatus and kept at a temperature of 65°C for 15 minutes. The homogeneous melt is poured into a mold preheated to 55°C. The mold is then cooled and the casting is removed when cool. The application example gives a very opaque silver lipstick with a metallic sheen when applied.

[0047] Example UE5: Nail Polish [Table 18] 0.5 g of the pigment obtained in Example 7b is weighed out with 24.5 g of REF BASE 12898 nail polish base from International Lacquers nailpolish&care, mixed well by hand with a spatula, then homogenized in a Hauschild DAC 150 FVZ Speedmixer at 1200 rpm for 4 minutes.

Claims

1. An effect pigment, comprising at least one TiO 2 The layer includes TiO 2 Ti III+ An effect pigment based on a flake-like substrate, characterized by being doped with fluoride.

2. The aforementioned flake-like substrate is synthetic or natural mica flakes, phyllosilicate, glass flakes, SiO 2 Flakes, Al 2 O 3 Flakes, TiO 2 The effect pigment according to claim 1, characterized in that it is selected from the group consisting of flakes, graphite flakes, and BiOCL flakes.

3. The synthetic mica flakes, glass flakes, TiO 2 flakes, SiO 2 flakes, Al 2 O 3 flakes are characterized by being doped or undoped, the effect pigment according to claim 2.

4. The effect pigment according to claim 3, characterized in that the doping ratio in the flake-like substrate is 0.01 to 5% by mass based on the substrate.

5. The TiO 2 Ti in the layer III+ The degree of fluoride doping is given by the formula TiF y O 2-x-y in accordance with During the ceremony, 0.00001 < y < 0.05 and 0.0001<x<0.1 The effect pigment according to claim 1, characterized in that it is the same as described above.

6. The aforementioned pigment has the following layered structure: - Substrate + TiO 2 - Substrate + SnO 2 +TiO 2 - Substrate + TiO 2 +SiO 2 +TiO 2 -Base material + SnO 2 +TiO 2 +SiO 2 +SnO 2 +TiO 2 - Substrate + TiO 2 +MgO+TiO 2 -Base material + SnO 2 +TiO 2 +MgO+SnO 2 +TiO 2 - Substrate + TiO 2 +CaO +TiO 2 - Substrate + SnO 2 +TiO 2 +CaO+SnO 2 +TiO 2 - Substrate + TiO 2 +SrO+TiO 2 -Base material + SnO 2 +TiO 2 +SrO+SnO 2 +TiO 2 - Substrate + TiO 2 +BaO+TiO 2 -Base material + SnO 2 +TiO 2 +BaO+SnO 2 +TiO 2 - Substrate + TiO 2 +ZnO +TiO 2 - base material+SnO 2 +Timi 2 +ZhnO+SnO 2 +Timi 2 、 In the formula, at least one TiO 2 The layer is Ti III+ The effect pigment according to claim 1, characterized in that it is doped with fluoride.

7. One or more of the aforementioned effect pigments TiO 2 The effect pigment according to claim 1, characterized in that the layer is additionally doped with niobium, zirconium, yttrium, magnesium, calcium, strontium, barium, zinc, indium, or antimony.

8. The effect pigment according to claim 1, characterized in that the pigment is further provided with an organic or inorganic coating as an outer layer on its surface.

9. at least one TiO 2 A method for preparing an effect pigment according to any one of claims 1 to 7, characterized by reacting an effect pigment based on a layered flake substrate with a fluoride donor, a solid reducing agent, and optionally a molten salt in a reducing gas mixture at a temperature of 700 to 900°C.

10. The method according to claim 9, characterized in that the fluoride donor is selected from the group consisting of inorganic fluorides, organofluorine compounds, and natural and synthetic fluorine-containing minerals.

11. The reducing agent is an alkaline earth metal, B, Al, Si, Zn, Fe, LiH, CaH 2 NaBH 4 , MgSi, MgSi 2 Ca 2 Si, CaSi 2 The method according to claim 9, characterized in that it is selected from the group.

12. Use of the effect pigment according to any one of claims 1 to 8 for paints, powder coatings, inks, plastics, films, radar-permeable finishes, electrostatic dissipative formulations, coatings for radar sensors, printing inks, security printing, security features for documents and identification cards, seed coloring, food coloring, or pharmaceutical coatings, laser marking, and for the preparation of pigment preparations and dried preparations, in cosmetic formulations, in high-temperature applications, and in pigment preparations.

13. Use of an effect pigment according to any one of claims 1 to 8 in a mixture of organic or inorganic dyes and / or pigments.

14. Use of the effect pigment according to claim 13 in a mixture with an aluminum pigment.

15. A formulation comprising the effect pigment described in any one of claims 1 to 8.

16. The formulation according to claim 15, characterized in that, in addition to the effect pigment described in any one of claims 1 to 8, it comprises at least one component selected from the group consisting of absorbents, astringents, antimicrobial substances, antioxidants, defoamers, antistatic agents, binders, biological additives, bleaching agents, chelating agents, deodorants, emollients, emulsifiers, emulsifying stabilizers, dyes, wetting agents, film-forming agents, fillers, aromatic substances, flavors, insecticides, preservatives, antimicrobial agents, cosmetic oils, solvents, oxidizing agents, plant components, buffering substances, reducing agents, surfactants, propellant gases, opacifiers, UV filters, UV absorbers, denaturants, viscosity modifiers, fragrances, vitamins, enzymes, trace elements, proteins, carbohydrates, organic pigments, inorganic pigments, carbon black, effect pigments, metallic pigments, and metallic-effect pigments.

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