DE19502231A1 - Effect pigment with dark body colour useful in plastics, paint, lacquer and cosmetics - Google Patents

Abstract

Effect pigment with dark body colour is based on a lamellar substrate, having (a) 1 or more coatings, in which case the outermost coating contains TiO2 and C black, or (b) 2 or more coatings, in which case the outermost contains TiO2 and the next contains C black. Any other coating(s) present contain metal oxide(s). The pigment is obtd. by subjecting the coated substrate to a redn. reaction at 500-1000 deg C under inert gas conditions. Also claimed is an effect pigment with dark body colour, based on a lamellar substrate with the specified outer coating(s) and opt. metal oxide and/or hydrated metal oxide coating(s), obtd. by mixing the metal oxide-coated substrate and C black without liquid medium, using a high-speed stirrer, suspending the coated substrate in aq. medium and depositing an outermost layer of Ti oxide and/or hydrated oxide by hydrolysis of suitable Ti salt(s) present in the medium.

Description

The present invention relates to effect pigments darker body color.

Flaky pigments based on flaky Substrates made with titanium suboxide and / or titanium oxide nitride the and optionally titanium dioxide are coated, and methods for producing such pigments are in described in the literature many times. These pigments are essentially characterized by a dark body color from green to teal, blue, gray and gray-blue to blackish and black.

In JP 59-126 468 z. B. platelet-shaped pigments described on the basis of mica substrates that with a layer of titanium dioxide and titanium suboxides and / or Titanium nitrides are coated. It is proposed these pigments e.g. B. by reduction of with titanium dioxide coated mica with a reducing gas like To produce hydrogen or ammonia gas by the with titanium dioxide coated mica with metallic Titan mixed and then the mixture obtained under vacuum at elevated temperature or on others Way reduced. The pigments are said to have a light shade have.

JP 60-60 163 contains platelet-shaped pigments the basis of mica substrates described with a first layer of titanium suboxides or titanium nitrides the coated and with a second layer of titanium are coated with dioxide. This will essentially be the same manufacturing methods as in the JP 59-126 468 proposed uses. The pigments are supposed to be a body color that ranges from green to blue to bluish violet ranges, and an excellent inter have reference color, preferably by choosing one suitable layer thickness is adapted to the body color.  

JP 58-164 653 describes a process for the production pearlescent pigment with dark pearlescent, in which one with titanium dioxide and possibly others Metal oxides coated mica at elevated temperatures treated with ammonia gas, causing the titanium dioxide to Titanium monoxide is reduced. The received here Pigments have a body color that is dark blue ranges from bluish black to black, and points Pearlescent on.

WO 93/19 131 describes a process for the production platelet-shaped color pigments described, in which one platelet-shaped substrates coated with titanium dioxide with one from the group of alkaline earth metals, B, Al, Si, Zn, Fe, LiH, CaH₂, Al₄C₃, Mg₂Si, MgSi₂, Ca₂Si or CaSi₂ out chose reducing agents in solid form in one oxidizing gas atmosphere at elevated temperature reduced. The body color that can be achieved here ranges from gray to yellowish black and bluish black to too black, the interference color being a variation ren of the titanium oxide layer thicknesses can vary.

Another class of pearlescent pigments with darker Body color is that of the carbon black inclusion pigments which, for. B. in US 4,076,551 and DE 42 22 372. These Pigments are based on platelet-shaped substrates that with a layer of one or more metal oxides and / or hydroxides are coated, in which soot Chen small size are stored.

Meet the pigments described in the prior art not all aesthetics of dark effect pigments requirements in a satisfactory manner. It z. B. an ever increasing need for effect pig elements with a dark body color that have a high chroma or have a high saturation of the interference color. The Chroma cannot be improved simply by increasing the Layer thickness of the applied layer or layers increase, as this increases the absorption of the incident and  reflected light increases and thus the chroma of the Interference color is lowered.

The object of the present invention was Provision of new effect pigments with a dark body color, the optical properties of which are different aesthetic requirements to others and / or satisfied more representative than that in the prior art Pigments described in the technique. Another job of present invention was to provide new effect pigments with dark body color, through which the range of previously available pigments of this type is widened and / or completed. Other goals the present invention are known to those skilled in the art from following detailed description can be seen easily.

It has been found that these tasks are provided by Provision treatment of the effect pigments according to the present invention can be solved.

The invention thus relates to an effect pigment darker body color based on a platelet-shaped Substrate covered with one or more layers gene, with the outermost layer being titanium oxide and contains soot, or that with two or more Layers is covered, with the outermost layer being titanium oxide and the second outermost layer Soot contains, if any further layers one or more metal oxides included, whereby the effect pigment is available that the coated platelet Substrate at about 500-1000 ° C of a reduction reaction undergoes under inert gas conditions. Furthermore concerns the invention a method for producing this Effect pigments, which is characterized in that the platelet-shaped substrate with one or more ren layers is coated, the outermost layer Contains titanium oxide and / or oxide hydrate and carbon black, or that is covered with two or more layers, the  outermost layer of titanium oxide and / or oxide hydrate and the second outermost layer contains soot while the given if available further layers one or more Contain metal oxides and / or oxide hydrates, with a reducing component and optionally a metal mixed halide and then at about 500-1000 ° C, preferably at 700-900 ° C under inert gas conditions glows.

The invention further relates to effect pigments darker body color based on a platelet-shaped Substrate covered with one or more layers gene, the outermost layer being based on soot, or that is covered with two or more layers, the outermost layer of titanium oxide and the second outermost layer contains soot while the given if available further layers one or more Contain metal oxides caused by this are available that a mixture of platelet migen substrate, optionally with one or more ren layers of one or more metal oxides and / or oxide hydrates is coated, and soot without liquid medium undergoes a rapid stirring process that resulting coated platelet-shaped substrate optionally suspended in an aqueous medium and one or more metal oxides and / or hydroxides Hydrolysis of the corresponding one or more metal solution containing salts as the outermost layer on the Substrate fails. Such effect pigments occur the production of the effect pigments described above as Intermediate levels.

Furthermore, the invention relates to the use of the new Effect pigments and the new intermediate from platelets shaped substrate for pigmenting plastics, Paints, varnishes and cosmetics.

The various claimed effect pigments are based on flaky substrates, which are preferably made of  the group of natural or synthetic mica, other layered silicates such as talc, kaolin or sericit or glass plates are selected. Also come too Metal plates such as B. aluminum plate or plate Chen-shaped metal oxides such. B. platy Iron oxide, silicon dioxide or bismuth oxychloride in Question, this list only as an example and should not be interpreted as a limitation of the invention. Natural or synthetic are particularly preferred Mica, other layered silicates or glass plates and especially natural or synthetic mica.

The platelet-shaped substrates preferably have in the main direction an extent of less than 500, especially less than 250 µm and very special less than 100 µm and a thickness of preferably less than 10, especially not more than 5 and particularly preferably between 0.1-3 µm. The relationship the extension in the main direction to the thickness of the leaves Chen-shaped substrates (aspect ratio) is more than 5 and preferably more than 10.

At the beginning, the lamellar substrates can be used be coated with one or more layers, each one or more from the group consisting of:

Titanium oxide, tin oxide, zirconium oxide, zinc oxide, iron oxide, chromium oxide, aluminum oxide, cobalt oxide, nickel oxide and the corresponding oxide hydrates
selected metal oxides and / or oxide hydrates hen.

These pre-coated substrates and processes for their Manufacturing are known per se and z. B. in Deut patents and patent applications 14 67 468, 19 59 998, 20 09 566, 22 14 454, 22 15 191, 22 44 298, 23 13 331, 25 22 572, 31 37 808, 31 37 809, 31 51 343, 31 51 354, 31 51 355, 32 11 602 and 32 35 017. At  the Beschich described in these references ting process is wet chemical coating methods, but other methods such as Evaporation (CVD process) are used.

The layer thickness of this applied as a pre-coating Coatings are between 40 and 500 nm, and the The weight fraction of the individual layers is between 5 and 200 wt .-%, based on the weight of the uncoated flaky substrate.

The effect pigments are particularly preferably based on the present invention on translucent or semi-permeable leaflet-shaped substrates, in particular on natural or synthetic mica substrates ten uncoated or with no more than one Layer are precoated.

A preferred embodiment of an effect pigment with dark body color according to the present invention is shown schematically in FIG. 1. The optionally pre-coated flaky substrate ( 1 ) is coated with a first layer ( 2 ) based on carbon black. Such effect pigments are referred to below as effect pigments (I).

The effect pigments (I) are prepared by mixing the optionally pre-coated platelet-shaped substrate ( 1 ) with carbon black and optionally with further pigment components and / or further components. The mixture is then subjected to a treatment at high stirring speed without a liquid medium. This mechanical-chemical process is described in detail in EP 0 554 776.

The mixer used here gives the mixture preferably a stirring energy of 290 J or more per Grams of mixture. This is preferably as the speed measured stirring speed 30 m / s or more. Of the  exact geometric structure or other characteristics of the Mixers are less critical, being those on the market available intensive mixer such. B. from the company Dynamics Co., USA, manufactured mixer 36FL23 can be used are.

The average size of the soot particles used is preferably less than 1000 nm. Very small particles with an average particle size below 100 nm and in particular below 50 nm are preferred. Especially preferred is carbon black, the average particle size of which is 10-30 nm is.

The amount of carbon black used is preferably not more than 50% by weight, in particular less than 20% by weight, and above all it is between 0.05-8.0% by weight and very particularly between 0.5-3. 0 wt .-%, based on the mass of uncoated platelet-shaped substrate ( 1 ), ie based on its mass before a possible subsequent coating.

The one used in the mechanical-chemical process Mixture can still other components, especially one or contain several pigment components, each from pigment particles with an average grain size of 5 µm or less, preferably 2 µm or less and especially with an average grain size in the submicron area exist. Suitable pigments are in EP 0 554 776 listed. Inorganic are particularly preferred Pigments such as B. Pigment White 6, Pigment White 21, Pigment Yellow 42, Pigment Red 101, Pigment Violet 16, Pigment Brown 6, Pigment Black 11 and Pigment Black 22 as well as organic pigments such as B. Pigment Yellow 108, Pigment Red 149, Pigment Blue 15: 3, Pigment Blue 61: 1, Pigment Green 7, Pigment Brown 23, Pigment Black 1, Pigment Black 31 and Pigment Yellow 101.

The addition of pigment components other than carbon black and given if necessary further components to the mixture leads to  special color effects and is from an aesthetic point of view often highly desired. On the other hand, the mechanical stability of the on the leaflet-shaped Substrate (1) applied coating sometimes disadvantageous lig influenced, especially when the particles of the additional pigment component or components have quite high medium size. The amount of additional Licher pigment component or additional pigment com components, based on the mass of the soot component, is preferably less than 50% by weight and whole especially less than 30% by weight.

The layer thickness of the coating which is mechanically and chemically applied to the optionally pre-coated flaky substrate ( 1 ) is preferably less than 1000 nm and in particular not more than 500 nm. If the coating consists exclusively of carbon black, the layer thickness is preferably less than 500 nm and in particular especially not more than 350 nm.

In a particularly preferred embodiment this first coating exclusively from soot. The effect pigments (I) and in particular the preferred embodiment Forms of effect pigments (I) are usually from lower brightness than comparable soot inclusion pig ment.

The composition of the coated flaky substrate ( 1 ) has proven to be less critical. In particular, it is based on the substances specified as the preferred substrate, which are coated with one or more, in particular one or two layers, each of one or more metal oxides, which are preferably selected from the group of the metal oxides mentioned above.

In a particularly preferred embodiment, the uncoated platelet-shaped substrate ( 1 ) is provided with coating layers which result in improved weather resistance. Such coatings are e.g. B. in EP 0 268 918 or EP 0 342 533.

In a further preferred embodiment, the effect pigments (III) and (IV) according to the present invention described below are used as platelet-shaped substrates ( 1 ) in this mechanically chemical post-coating step.

The specified platelet-shaped substrates ( 1 ) are only to be understood as examples and serve to illustrate the invention without restricting it. The mechanical-chemical post-coating step is generally applicable to platelet-shaped pigments.

If the platelet-shaped substrates ( 1 ) are subjected to a mechanical-chemical post-coating step as described, this leads to a change in the optical properties of the platelet-shaped substrate and, moreover, these pigments are given new functional properties.

By applying an essentially soot-based coating, the flaky substrate ( 1 ) is given a darker body color while increasing the chroma. Cover layers with pigment components other than carbon black show a number of different color effects, but are also characterized by a high chroma. From an aesthetic point of view, the change in body color and especially the combination of a dark to very dark body color and a high chroma turns out to be very advantageous.

It has also been shown that the mecha African-chemical reaction step of the type described manufactured top layer a high abrasion resistance has what with coating layers based on soot or consist only of it, as special  is surprising to look at.

Furthermore, it has been found that when the additional mechanical-chemical post-coating layer is applied to a flake-shaped substrate ( 1 ) which contains one or more layers which give it high resistance to weathering, this property of the weather resistance is not or not at all due to the post-coating small and in any case acceptable level is adversely affected.

In FIG. 2 shows another preferred form of execution is the effect pigments with dark body color according to the present invention is shown, which are referred to as effect pigments (II). The optionally precoated platelet-shaped substrate ( 1 ) is provided with a first layer ( 2 ) based on carbon black, which is then coated with a second layer ( 3 ) containing titanium dioxide or oxide hydrate.

The effect pigments (II) are produced by Dispersion of the effect pig obtained as an intermediate elements (I) in an aqueous solution and coating with a second layer based on titanium dioxide or -oxide hydrate according to and well known in the art e.g. B. in US 3,087,828 and US 3,553,001 procedure. Coatings on are particularly preferred the base of TiO₂ in the rutile modification, e.g. B. according to the in the US 4,086,100 or U.S. 4,867,794 have it made.

If necessary, the second layer can consist of one or several other metal oxides than Titanium oxide exist. Such together set layers can be made by joint precipitation produce various metal oxides or metal oxide hydrates, like this B. in US 4,494,993, US 4,509,988 or EP 0 096 284. The amount of TiO₂ or  that is preferably however at least 65% by weight and in particular not less than 75% by weight based on the mass of the second Coating layer. The second coating layer can be also by means of a CVD reaction (chemical vapor deposi tion).

In a particularly preferred embodiment the second coating layer exclusively made of TiO₂.

The layer thickness of the second coating is preferably in the range from 10 to 1000 nm and in particular from 40 to 500 nm.

In the case of a wet-chemical coating step, which is preferred, the product resulting from the coating reaction is filtered off, washed with deionized water, dried at moderately high temperatures below 300 ° C. and optionally annealed at temperatures between 600-1000 ° C. the effect pigments (II) of FIG. 2 are obtained.

The effect pigments (II) have advantageous properties, in particular a preferred combination of relatively low brightness values and relatively high chroma values, as can be seen from FIG. 6. This particular combination of L and C values is particularly desirable from an aesthetic point of view.

In FIG. 3, another preferred execution form is the effect pigments with dark body color according to the present invention is shown, which are referred to as effect pigments (III). The effect pigments (III), which are obtained by a reduction reaction of the effect pigments (II), consist of a possibly pre-coated platelet-shaped substrate ( 1 ) which is coated with a first layer ( 2 ) based on carbon black. This layer ( 2 ) is covered with a second layer ( 4 ) which is obtained by a reduction reaction of the layer ( 3 ) containing titanium dioxide and / or oxide hydrate.

In a preferred embodiment, such a reduc tion reaction, the effect pigment (II) with a reducing component mixed and then at Temperatures between 500-1000 ° C, especially between Annealed at 700-900 ° C.

The reducing component preferably consists of one or more reducing agents selected from the group solid reducing agents are selected, which result from Alkaline earth metals, B, Al, Ti, Si, Zn, Fe, LiH, CaH₂, Al₄C₃, Mg₂Si, MgSi₂, Ca₂Si and CaSi₂ composed.

Furthermore, alloys of Metals or metal borides, carbides and silicides for Come into play. The well-known as reducing agents Alkali metals can also, preferably in liquid or gaseous phase. It is also possible gaseous reducing agents such as hydrogen gas, NH₃ gas, CO gas, etc. to use. This gaseous Reducing agents are preferably used with an inert Gas component mixed for better reaction management to guarantee.

Combinations of these reducing agents are also possible with each other.

Solid reducing agents, which are preferred are usually available as fine powders and are included the effect pigment (II) intimately mixed. Especially before trains are finely powdered elements such. B. Al, Si, Ca. and B or their combinations. Is particularly preferred finely powdered metallic silicon.

Preferably, the effect pigment (II) is mixed with a solid reducing component and then at about 500-1000 ° C, especially between 700-900 ° C, in a non-oxidizing gas atmosphere such as N₂, Ar, He, CO₂, C _x H _y , H₂ , NH₃ or annealed under vacuum conditions. Annealing in the presence of a solid reducing component under inert gas conditions, in particular in an atmosphere of N₂ or Ar, is particularly preferred. It should be noted that in the presence of N₂ or NH₃ in addition to TiO₂-x can also form TiN or TiON.

The body color of the resulting effect pigment (III) can be changed

• - the type of solid reducing agent (high reduc potential results in darker shades) and
• - The amount of solid reducing agent, the duration of the Reduction treatment and / or the reaction temperature

vary.

The amount of reducing component is preferably 1-50% by weight, particularly preferably 2-30% by weight, based on the proportion by weight of the second coating layer ( 3 ) of the effect pigment (II). The weight ratio of uncoated flaky substrate ( 1 ) and reducing component is preferably in the range from 200: 1 to 1: 1, in particular from 100: 1 to 10: 1.

A reaction temperature of more is preferably chosen than 600 ° C, particularly preferably between 700-1000 ° C and before all between 700 and 900 ° C. The duration of the reduction reaction is preferably more than 10 minutes and is particularly preferably between 15 and 60 minutes.

Below are some examples of the reduction reaction for the cases where the coating layer ( 3 ) of the effect pigment (II) consists only of TiO₂:

If the second layer ( 3 ) contains one or more metal oxides other than titanium dioxide, the composition of the layer ( 4 ) of the effect pigment (III) is more complicated since it also contains lower oxides of the other metal oxides.

By adding a halide, preferably a Chlo rids, to the reaction mixture can the reduction reaction be accelerated. Particularly preferred additives are LiCl, NaCl, KCl, MgCl₂, CaCl₂, CuCl₂, CrCl₃, MnCl₂, FeCl₂, FeCl₃, CoCl₂, NiCl₂ or CeCl₃. The reaction temp temperature can usually be around 150- in the presence of chloride 300 ° C can be reduced.

The amount of halide and especially chloride compo can be between 0.1-40% by weight, preferably 0.5-10 % By weight, based on the mass of the platelet-shaped Intermediate stage, fluctuate.

The effect pigments (III) obtained have the ver various, aesthetically very appealing shades that from dark red to dark green, dark blue, dark purple to dark gray and even darker shades chen.

The range of attainable colors can be seen through  Coating the effect pigment (III) with one or several, preferably an additional coating layer, each made of one or more metal oxides and / or oxide hydrates, each preferably from the following group of metal oxides and / or -oxide hydrates:

Titanium oxide, tin oxide, zirconium oxide, zinc oxide, iron oxide, chromium oxide, aluminum oxide, cobalt oxide, nickel oxide and the corresponding oxide hydrates
selected, still expand.

The effect pigment (III) is subsequently coated preferably according to the above for the precoating of Method specified platelet-shaped substrates.

Effect pigments (III) are particularly preferred Base of an uncoated flaky substrate, that with a first layer of soot and a second Layer of TiO₂ or the corresponding oxide hydrate is coated, this being obtained as an intermediate Effect pigment of type (II) through a reduction reaction is converted to the effect pigment of type (III).

4 is a schematic representation of a another preferred embodiment of the effect pigments with dark body color according to the present invention can be seen, which in the following as effect pigments (IV) be designated. The effect pigment (IV) is obtained by a reduction reaction of a pigment on the Basis of an optionally pre-coated leaflet migen substrate that with a layer of titanium oxide or oxide hydrate and optionally further metal oxides or -oxide hydrates is coated in the soot and given if other small pigment particles are stored. The effect pigment (IV) thus consists of a given if pre-coated flaky substrate, the is covered with a layer (5), which is covered by a  Reduction reaction of the inclusion layer is obtained.

Unreduced inclusion pigments are in the literature described. In US 4 076 551 e.g. B. a pigment described that by suspending the substrate in an aqueous medium, the soot particles with a part Chen size below 1 micron, and then Deposition of the layer of metal oxide or oxide hydrate or bismuth oxychloride on the substrate. In the EP 0 499 864 has been proposed to use such pigments Increase their abrasion resistance with an increased Temperature between 700-900 ° C in an inert gas atmosphere to glow. Another improvement in abrasion resistance stands can still be achieved by using the Soot particles using an ionic surfactant, one not ionic surfactant and an organofunctional silanever bond in the matrix of metal oxide or oxide hydrate attached, as suggested in DE 42 22 372 becomes. In WO 93/11 194 another type of Inclusion pigment suggested, the other pigment part Chen contains soot, which is in a layer of metal oxide are stored.

These known inclusion pigments and their modifications tions can all be treated according to the undergo the present invention.

In the present invention, the platelet-shaped substrate ( 1 ) is preferably selected from the same substances mentioned above as the substrate, both an uncoated one and one or more layers of one or more metal oxides or oxide hydrates, which are preferably selected from from the above listing of metal oxides or metal oxide hydrates, pre-coated substrate can be used.

This is done to produce the effect pigments (IV) provide the inclusion layer in the form of a chen-like substrate, whose metal oxide matrix preferably on titanium dioxide  based, but also one or more other metal oxides or can contain oxide hydrates, which preferably consist of the following group of metal oxides or oxide hydrates are selected, which consist of tin oxide, zirconium oxide, Zinc oxide, iron oxide, chromium oxide, aluminum oxide, cobalt oxide, nickel oxide and the corresponding oxide hydrates put together. The percentage of titanium oxide is preferably 60% by weight or more and in particular not less than 75% by weight, based on the Mass of the metal oxide matrix. Are particularly preferred Inclusion pigments based on flake-like Substrates where the metal oxide matrix of the coating layer consists of titanium dioxide.

The particles preferably have the embedded Soot or other pigments are small in size and have especially an average particle size of less than 2 µm, preferably less than 1 µm, very particularly of no more than 200 nm and especially between 10-50 nm on. The other pigments are preferably from the selected above list of pigments selected, can, however, also from other organic or inorganic pigments selected. The percentage of Carbon black pigments is preferably at least 60% by weight and in particular not less than 75% by weight, based on the Mass of the pigment component stored. Especially inclusion pigments are preferred, the embedded ones Pigment component consists exclusively of soot.

The mass of the confinement layer, which is both the metal oxide matrix as well as the embedded pigment component comprises, preferably varies between 10-300 wt .-% and in particular between 15-200 wt .-%, based on the Mass of uncoated or pre-coated papers shaped substrate. The weight percentage of the stored Pigment component usually fluctuates between 0.5-50 % By weight and in particular between 2-30% by weight, based on the mass of the confinement layer.  

The inclusion pigments are preferably produced by conventional wet chemical methods, such as e.g. B. in US 4 076 551, EP 0 499 864, DE 42 22 372 and WO 93/11 194 are described.

As a result of the subsequent reduction reaction of the inclusion pigments, in which one preferably works under the same reduction conditions as described above, the inclusion layer is transferred into layer ( 5 ).

The effect pigments (IV) thus obtained have the various dark, aesthetically very appealing Colours. Furthermore, they often show interesting opti cal properties such. B. a double flop of Inter reference color.

The range of colors that can be achieved can be determined by layers of the effect pigment (IV) with one or more ren, preferably an additional coating layer, the each of one or more metal oxides and / or -oxide hydrates, each preferably consisting of following group of metal oxides and / or oxide hydrates:

Titanium oxide, tin oxide, zirconium oxide, zinc oxide, iron oxide, chromium oxide, aluminum oxide, cobalt oxide, nickel oxide and the corresponding oxide hydrates
selected, still expand.

The effect pigment (IV) is subsequently coated preferably according to the above for the precoating of Method specified platelet-shaped substrates.

Effect pigments (IV) on the Base of an uncoated flaky substrate, that with a first layer of soot and a second Layer of TiO₂ or the corresponding oxide hydrate is coated, this pigment by a  Reduction reaction to effect pigment (IV) is implemented.

The effect pigments (I) - (IV) according to the present Invention represent a significant asset to the Range of technically usable pigments they are of considerable economic importance.

The effect pigments (III) and are particularly preferred (IV) based on pigments containing carbon black, the be subjected to a reduction reaction. This pig elements have low brightness values and high ones Colorfulness.

The following examples are used for a more detailed description exercise of the invention without restricting it. Before and all temperatures below mean ° C.

example 1

50 g of mica with a particle size of 1-100 µm (mean particle size: 9 µm) and 0.76 g of carbon black (FW200, im Available from Degussa, middle section size: 13 nm) are placed in a high-speed mixer (36FL23, manufactured by Dynamics Co., USA). The mixture is stirred for 120 seconds at a speed of 72 m / sec and receives coated with soot in this way Mica particles.

This is suspended in 550 g of deionized water and the suspension is heated to 75 ° C. with constant stirring. 80 ml of a tin tetrachloride solution (53 g / l) are added dropwise at a pH of 1.5 too, which is equal to timely addition of 32% aqueous sodium hydroxide solution in keeps essentially constant. Then increase the pH to 1.8 and dropwise 422 ml of a titanium tetrachloride solution (423 g / l), the pH being adjusted by simultaneous Essentially add 32% aqueous sodium hydroxide solution maintains a constant value of 1.8.  

The coated particles are then filtered off washed, washed with deionized water and dried net. 10 g of the powder obtained are 0.26 g metallic silicon powder from Wako Junyaku Industries Co. and 0.40 g of anhydrous calcium chloride from Kanto Chemical Co. mixed. The mixture is in Crucibles placed in an electric tube furnace transferred, which is heated to 800 ° C for 30 minutes. During the reduction reaction is through the furnace tube Nitrogen passed.

The pigments obtained have a deep dark golden color Body color with pearlescent.

Examples 2-5

For the production of pigments one proceeded according to the Process described in Example 1, using the given amounts of titanium tetrachloride solution, metallic Silicon powder and calcium chloride as in the following Table indicated varied. The remaining reaction conditions conditions were chosen as indicated in Example 1.

The reaction conditions under which you can see in the example len 1-5 worked, and the appearance as well as the coloristi properties (Hunterlab) of the pigments obtained are summarized in Table 1.

Examples 6-10

50 g of mica with a particle size of 1-100 µm (mean particle size: 9 µm) and 0.76 g of carbon black (FW200, im Available from Degussa, middle section size: 13 nm) are placed in a high-speed mixer (36FL23, manufactured by Dynamics Co., USA). The mixture is stirred for 120 seconds at a speed of 72 m / sec and receives coated with soot in this way Mica particles.  

This is suspended in 550 g of deionized water and the suspension is heated to 75 ° C. with constant stirring. 80 ml of a tin tetrachloride solution (53 g / l) are added dropwise at a pH of 1.5 too, which is equal to timely addition of 32% aqueous sodium hydroxide solution in keeps essentially constant. Then increase the pH to 1.8 and a titanium tetrachloride solution (423 g / l) drips to, whereby the pH by simultaneous metering 32% aqueous sodium hydroxide solution essentially on one holds constant value of 1.8. The in Examples 6-10 amount of titanium tetrachloride solution used is the Table 2.

The coated particles are then filtered off tried, washed with deionized water, dried and heated to 800 ° C under nitrogen for 30 minutes.

The appearance and the coloristic properties (Hunterlab) of the pig obtained in Examples 6-10 elements are summarized in Table 2.

Example 11

50 g of mica with a particle size of 1-100 µm (mean particle size: 6 µm) and 1.55 g of carbon black (FW200, im Available from Degussa, middle section size: 13 nm) are placed in a high-speed mixer (36FL23, manufactured by Dynamics Co., USA). The mixture is stirred for 120 seconds at a speed of 72 m / sec and receives coated with soot in this way Mica particles.

This is suspended in 550 g of deionized water and the suspension is heated to 75 ° C. with constant stirring. 178 ml of a tin tetrachloride solution are added dropwise, (53 g / l) at a pH of 1.5 too, which is equal to timely addition of 32% aqueous sodium hydroxide solution in keeps essentially constant. Then increase the pH to 1.8 and dropwise 687 ml of a titanium tetrachloride solution (423 g / l), the pH being adjusted by simultaneous Essentially add 32% aqueous sodium hydroxide solution maintains a constant value of 1.8.

The coated particles are then filtered off washed, washed with deionized water and dried net. 10 g of the powder obtained are 0.31 g metallic silicon powder from Wako Junyaku Industries Co. and 0.46 g of anhydrous calcium chloride from Kanto Chemical Co. mixed. The mixture is in Crucibles placed in an electric tube furnace transferred, which is heated to 800 ° C for 30 minutes. During the reduction reaction is through the furnace tube Nitrogen passed.

The pigments obtained have a deep dark golden color Body color with pearlescent.

Example 12

100 g of a carbon black inclusion pigment, which according to Example 5  DE 42 22 372 was produced with 2 g metallic silicon powder (available from E. Merck) and 0.5 g of anhydrous calcium chloride (available by E. Merck) and mixed for 1 hour mixed vigorously.

30 g of the mixture are placed in crucibles which are placed in a electric tube furnace can be transferred to the 45 minutes is heated to 850 ° C. During the reduction reaction nitrogen is passed through the furnace tube.

The pigments obtained have a deep dark blue color Body color and the interference color shows a double color flop from blue to violet.

Example 13

100 g of a carbon black inclusion pigment, which according to Example 1 DE 42 22 372 was produced with 3.8 g metallic silicon powder (available from E. Merck) and 2 g of anhydrous calcium chloride (available by E. Merck) and mixed for 1 hour mixed vigorously.

30 g of the mixture are placed in pots, which are placed in a electric tube furnace can be transferred to the 45 minutes is heated to 900 ° C. During the reduction reaction nitrogen is passed through the furnace tube.

The pigments obtained have a gray body color and the interference color shows a double color flop of gray to blue.

Comparative Examples 14-18

50 g of mica with a particle size of 1-100 µm (mean particle size: 9 µm) are deionized in 550 g Suspended water and the suspension under constant  Stirring heated to 75 ° C. 80 ml of a tin are added dropwise tetrachloride solution (53 g / l) at a pH of 1.5 to, which is 32% aqueous by simultaneous metering Sodium hydroxide solution remains essentially constant. After that increased the pH is 1.8 and a titanium tetra is added dropwise chloride solution (423 g / l), whereby the pH by simultaneous metering of 32% aqueous sodium hydroxide solution in essentially at a constant value of 1.8. The amount used in Comparative Examples 11-15 Titanium tetrachloride solution is shown in Table 3.

The coated particles are then filtered off, washed with deionized water and dried. 10 g of the powder obtained are mixed with metallic silicon powder from Wako Junyaku Industries Co. and anhydrous calcium chloride from Kanto Chemical Co. The mixture is placed in crucibles which are transferred to an electric tube furnace which is heated to 800 ° C for 30 minutes. Nitrogen is passed through the furnace tube during the reduction reaction. The amounts of metallic silicon powder and anhydrous calcium chloride can be found in Table 3, which also summarizes the appearance and color properties (Hunterlab) of the pigments obtained in Comparative Examples 11-15.

The diagram brightness L against chroma C of Fig. 5 shows a comparison of color properties of the pigments according to Examples 1-5 (black circles) and examples 14-18 (white rings). It can be seen from this that the pigments from Examples 1-5 according to the present invention are darker and have a higher chroma than the corresponding conventional pigments from Examples 14-18 without the addition of carbon black.

The graph of brightness L versus chroma C of FIG. 6 shows the color properties of the pigments from Examples 1-10 according to the present invention. The unreduced pigments from Examples 6-10 (white triangles) have greater brightness and lower chroma than the pigments from Examples 1-5 (black rings), but the combination found for the pigments from Examples 6-10 is relative low brightness values and relatively high chroma values is advantageous from an aesthetic point of view.

Claims (13)

1. Effect pigment with dark body color on the base of a platelet-shaped substrate, which with a or more layers is coated, the outermost layer of titanium oxide and Contains soot, or that with two or more layers is coated with the outermost layer of titanium oxide and the second outermost layer Soot contains, if any further layers one or more metal oxides included, the effect pigment is obtainable by that the be layered platelet-shaped substrate at about 500 1000 ° C of a reduction reaction under inert gas subject to conditions. 2. Effect pigment according to claim 1, which thereby receives is that the coated plate-like Mixes substrate with a reducing component, which contains one or more reducing agents which are selected from the group of reducing agents, which consist of alkaline earth metals, B, Al, Si, Zn, Fe, LiH, CaH₂ Al₄C₃, Mg₂Si, MgSi₂, Ca₂Si and CaSi₂ together and then at 700-900 ° C under Inert gas conditions glow. 3. Effect pigment according to claims 1-2, characterized records that the platelet-shaped substrate from the Group of mica, mica-like iron oxide, layer silicate, flake-like oxides and metal flakes is selected. 4. Effect pigment according to claims 1-3, characterized records that the reduction reaction in the presence a metal halide is carried out. 5. effect pigment according to claim 4, characterized net that the metal halide from the group of Metal chlorides is selected, which consists of LiCl,  NaCl, KCl, MgCl₂, CaCl₂₁ CuCl₂, CrCl₃, MnCl₂, FeCl₂, FeCl₃, CoCl₂, NiCl₂ and CeCl₃ composed. 6. Effect pigment according to claims 1-5, characterized records that the outermost coating layer of the coated, titanium dioxide and Platelet-shaped substrate containing carbon black additionally Lich a non-ionic surfactant, an organofunctional nelle silane compound and an anionic or contains cationic surfactant. 7. effect pigment according to claims 1-6, characterized shows that the second outermost coating layer of the coated, soot-containing plate-like Substrate consists exclusively of soot. 8. effect pigment according to claims 1-7, characterized records that the platelet-shaped substrate with one or more layers is pre-coated, each of one or more metal oxides and / or Oxide hydrates from the titanium group oxide, cerocide, tin oxide, zinc oxide, zirconium oxide, Iron oxide, chromium oxide, cobalt oxide, nickel oxide, Manganese oxide, silicon oxide and / or the corresponding Oxide hydrates are selected. 9. Process for the preparation of effect pigments Claims 1-8, characterized in that the platelet-shaped substrate with one or more is covered, the outermost Layer of titanium oxide and / or oxide hydrate and soot contains, or that with two or more layers is covered, with the outermost layer of titanium oxide and / or oxide hydrate and the second outermost layer Soot contains, if any further layers one or more metal oxides and / or contain oxide hydrates, with a reduction renden component and optionally a metal mixed halide and then at 500-1000 ° C,  preferably at 700-900 ° C, under inert gas conditions is annealed. 10. The method according to claim 9, characterized in that the coated platelet-shaped substrate and the reducing agent in a weight ratio of 200: 1 to 1: 1, preferably from 100: 1 to 10: 1 be mixed. 11. The method according to claims 9-10, characterized net that to the mixture of coated substrate and reducing agent a metal halide in one Amount of 0.1-40% by weight, preferably 0.5-10 % By weight, based on the mass of the coated Substrate is given. 12. Effect pigments with a dark body color on the base of a platelet-shaped substrate, which with a or more layers is coated, the outermost layer based on soot, or that with two or more layers is covered, the outermost Layer of titanium oxide and the second outermost layer contains soot, while the any existing layers or several metal oxides included, whereby the effect pigments are obtained Lich are that a mixture of platelet according to the substrate, optionally with one or multiple layers of one or more metal oxides and / or oxide hydrates is coated, and Soot without liquid medium in a quick stirring process undergoes the resulting coated plate shaped substrate optionally in an aqueous Medium suspended and titanium oxide and / or oxide hydrate by hydrolysis of the corresponding one or solution containing several titanium salts on the sub strat deposits as the outermost layer. 13. Use of the new effect pigment and as  Intermediate obtained new platelet-shaped Substrate for pigmenting plastics, Paints, varnishes and cosmetics.