Metal Effect Pigments with High Chroma and High Brilliancy, Method for the Production and Use Thereof

Abstract

The invention relates to a metal effect pigment including a metallic substrate in platelet form and a coating applied thereto, wherein the coating includes a spacer layer. The invention further relates to a process for production of and to the use of the metal effect pigment.

Claims

1. A metal effect pigment comprising a metallic substrate in platelet form and coating applied to the substrate, wherein the coating comprises a) optionally a layer 1 comprising at least one of metal oxide, metal hydroxide or metal oxide hydrate, where the metal ion comprises or is at least one metal ion selected from the group of metals consisting of Al, Si, Sn, Mo and Zn, b) a layer 2 comprising at least one of metal oxide, metal hydroxide or metal oxide hydrate, c) a layer 3 comprising at least one of metal oxide, metal hydroxide or metal oxide hydrate, at least one of layers 2 and 3 contains at least two different metal ions and layers 2 and 3 are interrupted by a spacer layer.

2. The metal effect pigment as claimed in claim 1, wherein the metallic substrate in platelet form is selected from the group consisting of aluminum platelets, copper platelets, zinc platelets, iron platelets, titanium platelets, stainless steel platelets, silver platelets, alloys and mixtures of the above-listed metals.

3. The metal effect pigment as claimed in claim 1, wherein the effect pigment comprises further layers of high and low refractive index and optionally at least one further spacer layer.

4. The metal effect pigment as claimed in claim 1, wherein the at least two different metal ions of layer 2 and/or 3 are selected from the group of metals consisting of Ti, Fe, Sn, Mn, Zr, Ca, Sr, Ba, Ni, Sb, Ag, Zn, Cu, Ce, Cr and Co.

5. The metal effect pigment as claimed in claim 1, wherein the at least two different metal ions of layer 2 and/or layer 3 are selected from the group of metals consisting of Ti, Fe, Sn, Ag, Zr and Ce.

6. The metal effect pigment as claimed in claim 1, wherein the at least one spacer layer includes connections and cavities.

7. The metal effect pigment as claimed in claim 1, wherein the at least one spacer layer has a mean height h.sub.a in each case from a range from 5 nm to 120 nm.

8. The metal effect pigment as claimed in claim 1, wherein the at least one spacer layer is arranged essentially parallel to the surface of the metallic substrate in platelet form.

9. The metal effect pigment as claimed in claim 1, wherein the metal effect pigment, within the spacer layer, distributed over the entire metal effect pigment, measured using scanning electron of transverse sections, has an area proportion of cavities from a range from 51% to 99% and an area proportion of connections from a range from 1% to 49%.

10. A process for producing the metal effect pigment as claimed in claim 1, wherein the process comprises: (i) optionally applying an uncalcined metal oxide, metal hydroxide and/or metal oxide hydrate layer, where the metal ion comprises or is at least one metal ion selected from the group of metals consisting of Al, Si, Sn, Mo and Zn, to the metallic substrate in platelet form, (ii) sequentially applying three uncalcined layers A, B and C each consisting of or comprising at least one of metal oxide, metal hydroxide or metal oxide hydrate, where the layers A, B and C are arranged directly one on top of another and where the at least one metal oxide, metal hydroxide and/or metal oxide hydrate applied in the layer B, in relation to the metal ion, is different than the metal ion(s) of the metal oxides, metal hydroxides and/or metal oxide hydrates of layer A and layer C, (iii) calcining, optionally under reducing conditions, the product obtained in step (ii) at a temperature from a range from 320 C. to 970 C. to obtain the metal effect pigment comprising at least one spacer layer.

11. A process for producing the metal effect pigment as claimed in claim 1, wherein the process comprises: (i) sequentially applying two uncalcined layers B and C each consisting of or comprising at least one of metal oxide, metal hydroxide or metal oxide hydrate to a singly or multiply coated metallic substrate, where the layers B and C are arranged directly one on top of another and where the at least one metal oxide, metal hydroxide and/or metal oxide hydrate applied in the layer B, in relation to the metal ion, is different than the metal ion(s) of the metal oxide, metal hydroxide and/or metal oxide hydrate of layer C and of the layer which directly adjoins layer B in substrate direction, (ii) calcining, optionally under reducing conditions, the product obtained in step (i) at a temperature from a range from 320 C. to 970 C. to obtain the metal effect pigment comprising at least one spacer layer.

12. The process as claimed in claim 10, wherein the metal ions present in layer B diffuse at least partly into layer A and/or layer C to form the at least one spacer layer in the calcined effect pigment.

13. The process as claimed in claim 10, wherein the two or three sequentially applied metal oxides, metal hydroxides and/or metal oxide hydrates for production of the layers B and C or the layers A, B and C do not comprise or are not any metal ion selected from the group of metals consisting of Si, Mg and Al.

14. A process for producing a pigmented cosmetic formulation, plastic, film, textile, ceramic material, glass, paint, printing ink, writing ink, varnish, powder coating or a material for a functional application comprising introducing the metal effect pigment of claim 1 into a cosmetic formulation, plastic, film, textile, ceramic material, glass, paint, printing ink, writing ink, varnish, powder coating or a material for a functional application.

15. An article comprising at least one metal effect pigment as claimed in claim 1.

16. The method according to claim 11, wherein the metal ions present in layer B diffuse at least partly into layer A and/or layer C to form the at least one spacer layer in the calcined effect pigment.

17. The process according to claim 14, wherein the functional application is laser marking, IR reflection, or photocatalysis.

Description

I PRODUCTION OF THE METAL EFFECT PIGMENTS OF THE INVENTION

Example 1

[0165] A reaction vessel was initially charged with 215 g of aluminum paste (STAPA METALLUX Mex 214, NFA: 69.1%, from ECKART GmbH) together with 650 g of ethanol and dispersed for 10 minutes. Subsequently, 20.0 g of DM water (DM=demineralized) were added to the suspension and the mixture was heated to 75 C. Once the pH had been adjusted to pH 5.0 with acetic acid, 200 mL of a mixture of titanium(IV) isopropoxide and isopropyl alcohol in a volume ratio of 1:1 were dosed in gradually. On completion of addition, 10 g of demineralized water were added to the suspension and the mixture was stirred for a further 30 minutes. Subsequently, 30 mL of an ethanolic FeCl.sub.3 solution (w(FeCl.sub.3)=40.0%) were dosed in at constant pH. In the course of this, any rise in pH was counteracted with ethanolic NaOH w(NaOH)=10%. After the addition had ended, the mixture was left to stir for a further 30 minutes, then another 200 mL of a mixture of titanium(IV) isopropoxide and isopropyl alcohol were dosed in homogeneously in a volume ratio of 1:1. After all the additions had ended, the suspension was left to stir for a further 60 minutes, before being filtered with suction through a Bchner funnel while still hot and washed through with a mixture of ethanol and demineralized water in a volume ratio of 1:1. Lastly, the filtercake was washed with pure ethanol to free it of H.sub.2O and dried at 100 C. in a drying cabinet under an N.sub.2 atmosphere for 17 hours. The dried metal effect pigment was calcined at 500 C. under protective gas for 60 minutes.

Example 2

[0166] A reaction vessel was initially charged with 230 g of aluminum paste (ALOXAL PM 4010, NFA:65.9%, from ECKART GmbH) together with 630 g of ethanol and dispersed for 10 minutes. Subsequently, 20.0 g of demineralized water were added to the suspension and the mixture was heated to 75 C. Once the pH had been adjusted to pH 5.0 with acetic acid, 200 mL of a mixture of titanium(IV) isopropoxide and isopropyl alcohol in a volume ratio of 1:1 were metered in gradually. On completion of addition, 10 g of demineralized water were added to the suspension and the mixture was stirred for a further 30 minutes. Subsequently, 150 mL of an ethanolic FeCl.sub.3 solution (w(FeCl.sub.3)=40.0%) were dosed in at constant pH. In the course of this, any rise in pH was counteracted with ethanolic NaOH w(NaOH)=10%. After the addition had ended, the mixture was left to stir for a further 30 minutes, then another 200 mL of a mixture of titanium(IV) isopropoxide and isopropyl alcohol were dosed in homogeneously in a volume ratio of 1:1. After all the additions had ended, the suspension was left to stir for a further 60 minutes, before being filtered with suction through a Bchner funnel while still hot and washed through with a mixture of ethanol and demineralized water in a volume ratio of 1:1. Lastly, the filtercake was washed with pure ethanol to free it of H.sub.2O and dried at 100 C. in a drying cabinet under an N.sub.2 atmosphere for 17 hours. The dried metal effect pigment was calcined at 550 C. under protective gas for 60 minutes.

Example 3

[0167] Example 3 was conducted analogously to example 2, except that the starting material used, rather than ALOXAL PM 4010, was the SiO.sub.2-encapsulated aluminum effect pigment STANDART PCS 3500 (from ECKART GmbH).

Example 4

[0168] 200 g of STANDART PCS 3500 SiO.sub.2-encapsulated aluminum pigment from Eckart were suspended in 1300 mL of demineralized water and heated to 85 C. while stirring. The pH of the suspension was lowered to pH 2.2. By addition of 100 g of a tin chloride solution of concentration c(Sn)=12 g/L, a layer of SnO.sub.2 was deposited on the surface of the aluminum platelets.

[0169] After the mixture had been stirred for a further 20 minutes, a solution of 250 mL of TiCl.sub.4 (200 g of TiO.sub.2/L of demineralized water) was added to the suspension. After the end of the addition, the mixture was stirred for a further 10 minutes and then the pH was adjusted to pH 2.6. Subsequently, 60 mL of an aqueous iron chloride solution having a density of 1.42 g/cm.sup.3 were dosed in. On completion of metered addition, the mixture was stirred for another 10 minutes and, by addition of 100 mL of tin chloride solution of concentration c(Sn)=12 g/L, a further thin layer of tin oxide was deposited on the pigment surface. Subsequently, 250 mL of a solution of TiCl.sub.4 (200 g of TiO.sub.2/L of demineralized water) were dosed into the suspension. Thereafter, 12 mL of an aqueous iron chloride solution having a density of 1.42 g/cm.sup.3 were dosed in after 10 minutes. 15 minutes after completion of addition, the suspension was filtered off and the filtercake was washed. The filtercake was dried and calcined at 550 C. for 60 minutes under protective gas. Hiding, extremely chromatic, high-gloss golden metal effect pigments were obtained.

II CHARACTERIZATION OF THE METAL EFFECT PIGMENTS OF THE INVENTION AND PIGMENTS FROM THE COMPARATIVE EXAMPLES

IIa Particle Size Measurement

[0170] The size distribution curve of the metal effect pigments of the invention and pigments from the comparative examples was determined with an instrument from Quantachrome (instrument: Cilas 1064) according to the manufacturer's instructions. For this purpose, about 50 mL of the respective pigment were suspended in isopropanol, treated in an ultrasound bath (instrument: Sonorex IK 52, from Bandelin) for 300 seconds and then applied by means of a Pasteur pipette to the sample preparation cell of the measuring instrument and analyzed repeatedly. The individual measurement results were used to form the medians. The scattered light signals are evaluated by the Fraunhofer method.

[0171] The median particle size D.sub.50 in the context of this invention is understood to mean the D.sub.50 of the cumulative frequency distribution of the volume-averaged size distribution function, as obtained by laser diffraction methods. The D.sub.50 indicates that 50% of the pigments have a diameter equal to or less than the value reported, for example 20 m. Correspondingly, the D.sub.90 states that 90% of the pigments have a diameter equal to or less than the respective measured value. In addition, the D.sub.10 states that 10% of the pigments have a diameter equal to or less than the respective measured value.

IIb Aspect Ratio

[0172] The aspect ratio is defined as the ratio of median particle size D.sub.50 to mean thickness h of the metallic substrates in platelet form. The mean thickness of the metallic substrates in platelet form is reported in table 6.

TABLE-US-00001 TABLE 1 Particle sizes and aspect ratio Example/comparative D.sub.10 D.sub.50 D.sub.90 Aspect example [m] [m] [m] Span ratio Example 1 10.2 35.6 55.6 1.274 41 Example 2 2.2 34.0 56.8 1.604 56 Example 3 5.0 31.4 50.9 1.461 38 Example 4 4.8 30.6 51.2 1.516 36 Comparative 12.0 26.0 43.0 1.192 47 example 1

IIc Angle-Dependent Color Measurements and Hiding Quotient

[0173] To measure the color and brightness values, the metal effect pigments of the invention and the pigments from the comparative examples were stirred into a conventional nitrocellulose lacquer (Erco 2615e bronze mixing lacquer colorless; from Maeder Plastiklack AG) at a pigmentation level of 6% by weight, based in each case on the total weight of the wet lacquer. This was done by initially charging the respective pigments and then dispersing them into the lacquer with a brush. The finished lacquer was applied to black/white hiding charts (Byko-Chart 2853, from Byk-Gardner) in a wet film thickness of 76 m with a spiral applicator on an applicator drawdown apparatus (RK Print Coat Instr. Ltd. Citenco K 101 drawdown apparatus), and subsequently dried at room temperature.

[0174] The BYK-mac multi-angle colorimeter (from Byk-Gardner) was used to determine the color values on the black background of the hiding chart at a constant angle of incidence of 45 (according to the manufacturer's instructions) at various observation angles relative to the specular angle.

[0175] Characterization of the color intensity was accomplished using the chroma value C*.sub.15, which was measured at a measurement angle separated by 15 from the specular angle on the black background of the black/white hiding chart.

[0176] Strongly reflecting samples (mirrors in the ideal case) reflect virtually all the incident light at what is called the specular angle. The closer to the specular angle the measurement is made on the lacquer application, the more intense the appearance of the interference color.

[0177] To determine the hiding quotient D.sub.q, defined as D.sub.q=L*.sub.black.sup.25/L*.sub.white.sup.25, the brightness values L*25 of the above-described lacquer applications were recorded with the BYK-mac multi-angle colorimeter (from Byk-Gardner) at a measurement angle of 25 on the black and white backgrounds of the black/white hiding chart. The 25 measurement geometry, at a constant angle of incidence of 45, relates to the difference from the specular angle. The viewing angle is measured away from the specular reflection in the plane of illumination.

TABLE-US-00002 TABLE 2 Color values at observation angle of 15 relative to the specular angle Example/comparative L 15 a* 15 b* 15 example (s).sup.1 (s) (s) Example 1 118.93 0.02 2.58 Example 2 110.69 19.76 82.32 Example 3 116.90 0.22 3.59 Example 4 145.70 2.34 60.59 Comparative 127.93 22.86 73.45 example 1 .sup.1Measured on the black background of the black/white hiding chart.

IId Gloss Measurements

[0178] Gloss is a measure of directed reflection. To determine the gloss, the lacquer applications from IIc on the white background of the black/white hiding chart were analyzed at a measurement angle of 60 based on the vertical with the aid of a Micro-Tri-Gloss gloss meter from Byk-Gardner. The gloss values of the metal effect pigments of the invention and of the pigments from the comparative examples are listed in table 3.

[0179] Some of the inventive metal effect pigments from examples 1 to 4 show distinctly higher gloss values than the pigments having a single-layer coating from comparative example 1.

[0180] The gloss measurements from table 3 confirm the very high reflectivity of the pigments of the invention compared to the prior art.

IIe Effect Measurements

[0181] In order to objectively describe the optical effect of the metal effect pigments of the invention, effect measurements were conducted with the BYK-mac spectrophotometer (from Byk-Gardner) using the lacquer applications from IIc (cf. Byk-Gardner, catalog Qualittskontrolle fr Lacke and Kunststoffe [Quality Control for Lacquers and Plastics], 2011/2012, p. 97/98). The corresponding measurement values for the sparkle intensity S_i, the sparkle area S_a and the graininess G are collated in table 3.

TABLE-US-00003 TABLE 3 Effect measurements, hiding quotient and gloss Example/comparative S_i 15 S_a 15 G 60 gloss example (s).sup.1 (s).sup.1 (s).sup.1 D.sub.q 25 (w).sup.2 Example 1 18.94 32.47 12.03 0.931 24.9 Example 2 21.56 34.30 8.53 0.928 30.2 Example 3 14.70 29.11 10.64 0.926 29.6 Example 4 9.28 27.22 9.69 0.904 28.9 Comparative 2.99 4.32 2.89 0.999 25.6 example 1 .sup.1Measured on the black background of the black/white hiding chart. .sup.2Measured on the white background of the black/white hiding chart.

[0182] The effect values S_i, S_a and G of the inventive metal effect pigments from examples 1 to 4 are higher than the values for comparative example 1. The achievable optical effects of the inventive metal effect pigments are much more marked than in the case of conventional effect pigments with a single-layer coating from comparative example 1.

IIe Waring Blender

[0183] In industry, many lacquers are processed in circulation systems. In this case, the lacquer components are subjected to high shear forces. The Waring blender test simulates these conditions and serves for assessment of the ring line stability/shear stability. Specifically pigments wherein the coating has not been adequately anchored on the support material exhibit significant deviations in the chroma values in this test compared to the untreated applications. The Waring blender test can thus be regarded as a measure of the mutual adhesion of the pigment coating with respect to shear forces.

[0184] For this purpose, the metal effect pigments of the invention or the pigments from the comparative examples were weighed out according to the recipe below and converted stepwise to a paste with a conventional acrylic lacquer in an 880 mL beaker. Thereafter, the viscosity was adjusted with butyl acetate/xylene 1:1 to 17 in the DIN 4 mm cup. A total of 600 g of lacquer were produced, of which 400 g were introduced into a jacketed water-cooled 1 kg vessel and stirred with a specific attachment under the Dispermat (from Waring Blenders). The stirring time was 8 minutes at 13 500 rpm, then 200 g of lacquer were removed and the rest was stirred for a further 12 minutes. [0185] Recipe: 6% pigment [0186] 8% butyl acetate 85 [0187] 86% acrylic lacquer, colorless [0188] 30% dilution butyl acetate 85/xylene 1:1

[0189] 200 g each of the untreated and treated lacquers were applied to a test sheet with a spraying machine and the Sata LP-90 spray gun according to the following setting: [0190] Setting: Needle: 1.3.4 [0191] Pressure: 4 bar [0192] Runs: The number of spray runs was chosen such that there was a dry lacquer layer thickness of 15-20 m.

[0193] Conventionally, effect pigments are regarded as being shear-stable when the gloss differential and the color differential, measured close to the specular angle, are relatively low in the application after the Waring blender test. The C*.sub.15 value relative to the untreated sample should ideally be less than 2.

[0194] Table 4 shows the change in color C*.sub.15 and the change in gloss 60 gloss of the sample that has been subjected to the Waring blender test relative to the untreated sample for inventive examples 2 and 4.

TABLE-US-00004 TABLE 4 Gloss differential and color differential in the Waring blender test C* gloss (15) (60) Example 2 2.1 2.3 Example 4 2.6 1.9

[0195] The metal effect pigments of the invention from examples 2 and 4 fulfill the criteria of the test. The color difference is negligibly small. Even under the microscope, it is barely possible to detect any changes such as flaking of the coating or other surface defects that have arisen.

[0196] The metal effect pigments of the invention are found to be extremely shear-stable in spite of their spacer layer.

IIg X-Ray Fluorescence Analysis (XRF)

[0197] The metal oxide, metal hydroxide and/or metal oxide hydrate contents of the particles or pigments were determined by means of x-ray fluorescence analysis (XRF) from the powder bed. The measurements are shown in table 5. The figures for the different contents were reported here as TiO.sub.2 for titanium, as Fe.sub.2O.sub.3 for iron, as Al.sub.2O.sub.3 for Al, and if appropriate as ZrO.sub.2 for Zr, as SiO.sub.2 for Si, as Mo.sub.2O.sub.3 for Mo and as SnO.sub.2 for tin.

TABLE-US-00005 TABLE 5 XRF (as oxide) Ti Fe Al Example [%] [%] [%] Example 1 25.2 3.7 70.8 Example 2 33.3 4.4 60.2 Example 3 31.9 4.4 59.8 Example 4 28.6 14.6 55.4 Comparative <1 19 67.6 example 1
IIh Determination of the Mean Thickness of the Metallic Substrates in Platelet Form, the Mean Layer Thickness of Layers 1, 2 and 3, the Mean Layer Thickness of the Overall Coating, the Mean Height h.sub.a of the Spacer Layer and the Mean Height h.sub.H of the Cavities

[0198] For this purpose, the metal effect pigments of the invention were incorporated in a concentration of 10% into a two-component clearcoat, Autoclear Plus HS from Sikkens GmbH, with a sleeved brush, applied to a film with the aid of a spiral applicator (wet film thickness 26 m) and dried. After a drying time of 24 h, transverse sections of these applicator drawdowns were produced. The transverse sections were analyzed by SEM, with analysis of at least 100 individual pigments to be statistically meaningful for determination of the mean thickness of the metallic substrates in platelet form.

[0199] To determine the mean layer thickness of layers 1, 2 and 3, the mean layer thickness of the overall coating, the mean height ha of the spacer layer and the mean height h.sub.H of the cavities, the upper and lower substrate surfaces, i.e. the longer side in each case of the metallic substrate in platelet form, were each used as the baseline. The baseline was drawn here on the scanning electron micrograph of the transverse section by connecting the two points of intersection of metallic substrate in platelet formoptional layer 1 or of metallic substrate in platelet formlayer 2 from the left- and right-hand edges of the scanning electron micrograph of the transverse section to one another by means of a straight line. The scanning electron micrographs of transverse section were analyzed with the aid of the AxioVision 4.6.3 image processing software (from Zeiss).

[0200] A sufficient number of parallel lines were drawn at 50 nm intervals at a 90 angle from these two baselines as to place a grid over the complete scanning electron micrograph of the transverse section (FIG. 4). The magnification of the scanning electron micrograph of the transverse section was preferably at least 50 000-fold, based on Polaroid 545. Proceeding from the respective upper and lower baselines of the metallic substrate in platelet form in the direction of layer 3 in each case, the distances between the points of intersection of these lines at the respective interfaces of the optional layer 1-layer 2, layer 2-spacer layer, spacer layer-layer 3 and layer 3-environment were measured manually. It happened here that a line marked at 50 nm intervals was located directly above a connection point. In this case, only the respective point of intersection of the line at the interface of layer 3-environment was recorded. These measurements yielded the layer thicknesses of layers 1, 2 and 3, the thickness of the overall coating, and the height h.sub.a of the spacer layer by formation of differences.

[0201] For the determination of the mean height h.sub.H of the cavities, the points of intersection of these lines with the upper and lower cavity boundaries within the spacer layer were used.

[0202] For the determination of the thickness of the metallic substrate in platelet form, the points of intersection of these lines at the upper and lower substrate surface to the adjoining layer in each case were employed.

[0203] The individual values of the thickness of the substrate, the layer thicknesses, the height h.sub.a and the height h.sub.H that have been determined in this way were used to form the respective arithmetic means in order to determine the above-specified mean layer thicknesses, mean thicknesses of the metallic substrate in platelet form, the mean height h.sub.H and the mean height h.sub.a. To be statistically meaningful, the above-described measurements were conducted on at least 100 lines.

[0204] The term mean in all cases means the arithmetic mean.

[0205] Transverse sections of the pigments from the comparative examples that do not have a spacer layer but may have statistically distributed pores within the coating were likewise examined by the method described above using scanning electron micrographs of transverse sections. In this case, if one of the parallel lines occurred above one or more pores, the height of the pore(s), the pore midpoint(s) thereof and the distance of the pore midpoint(s) from the substrate surface were determined.

[0206] As an alternative to transverse sections, the metal effect pigments of the invention can also be cut by means of the FIB method (FIB=focused ion beam). For this purpose, a fine beam of highly accelerated ions (for example gallium, xenon, neon or helium) is focused to a point by means of ion optics and guided line by line over the effect pigment surface to be processed. On impact with the effect pigment surface, the ions release most of their energy and destroy the coating at this point, which leads to removal of material line by line. It is also possible using the scanning electron micrographs that have then been recorded, by the method described above, to determine the mean height h.sub.a, the mean layer thickness of layers 1, 2 and 3 and the mean layer thickness of the overall coating. The mean thickness of the metallic substrate in platelet form can also be determined using scanning electron micrographs of the metal effect pigments that have been cut by the FIB method.

TABLE-US-00006 TABLE 6 Example/comparative d.sub.S1 d.sub.S2 h.sub.a d.sub.S3 h.sub.ma h.sub.Rma d S.sub.D A.sub.H example [nm] [nm] [nm] [nm] [nm] h.sub.Rma [%] [nm] n.sub.S [%] [%] Example 1 / 53 16 49 60 0.51 3.6 860 14 65.6 34.4 Example 2 68 46 19 53 56 0.30 2.7 605 5 18.3 81.7 Example 3 46 50 21 58 52 0.30 4.1 834 3 21.8 78.2 Example 4 43 85 28 89 95 0.39 3.8 848 1 6.2 93.8 Comparative no spacer layer 0.53 22.3 556 17 95.0 5.0 example 1 d [nm] = mean thickness of the substrate d.sub.S1 [nm] = mean layer thickness of optional layer 1 d.sub.S2 [nm] = mean layer thickness of layer 2 d.sub.S3 [nm] = mean layer thickness of layer 3 n.sub.S = mean number of bars per m A.sub.H [%] = area proportion of cavities S.sub.D = network density [%] h.sub.ma = midpoint of the spacer layer (sum total of the layer thickness of the optional layer 1 and of layer 2 and half the height h.sub.a) h.sub.Rma = relative height of the spacer layer h.sub.Rma [%] = standard deviation of the relative height of the spacer layer h.sub.a = mean height of the spacer layer

[0207] In table 6, the network density of the metal effect pigments of the invention is much lower than in the case of the pigment from comparative example 1 with a value of 95%. Because of the extremely small number of pores, there is no spacer layer in the pigment from comparative example 1.

IIi Gassing Test

[0208] For the determination of the gassing stability, 15 g of the metal effect pigments of the invention and the pigments from the comparative examples were suspended in 20.0 g of butylglycol with a stirring time of 5 min. To this suspension were added 14.4 g of colorless binder (ZK26-6826-402, manufacturer: BASF Coatings) and 0.6 g of 10% dimethylethanolamine solution (solvent: water), and the mixture was stirred for 5 minutes.

[0209] 23.45 g of the suspension were stirred into a mixture of 233.1 g of milky/colorless mixed lacquer for effect substance testing (ZW42-6008-0101, manufacturer: BASF Coatings), 37.5 g of red waterborne basecoat tinting paste (ZU560-329-0001, manufacturer: BASF Coatings, containing iron oxide red, Fe.sub.2O.sub.3) and 6.0 g of black waterborne basecoat tinting paste (ZU42-5943-0001, manufacturer: BASF Coatings, containing iron oxide black, Fe.sub.2O.sub.3.FeO). Subsequently, the pH of the suspension was adjusted to 8.2 with 10% dimethylethanolamine solution (solvent: water).

[0210] 265 g of the above composition were introduced into a gassing bottle which was sealed with a twin-chamber gas bubble counter. The gas wash bottle was equilibrated at 40 C. in a water bath for 1 hour and sealed gas-tight, and the test was conducted over a maximum of 28 days. The gas volume formed was read off from the displaced volume of water in the upper chamber of the gas bubble counter. In the case of evolution of not more than 10 mL of hydrogen after 28 days, the test was considered to have been passed. The results of the gassing test are compiled in table 6.

IIj Powder Coating Application

[0211] 15 g in each case of the metal effect pigment of the invention or from the comparative example were mixed together with 285 g of the Tiger powder coating from Tiger Coatings GmbH & Co. KG and with 0.2% Aeroxide Alu C (from Evonik) in a commercial kitchen mixer from Vorwerk, ThermoMix, at level 4 for 4 minutes. The mixed powder coatings were applied to metal sheets with the OptiSelect (from ITWGema) in a commercial powder coating cabin.

[0212] The application characteristics, the presence of black spots and the structure and leveling of the powder coatings were assessed visually.

IIk Chemicals Test

[0213] The coated test sheet from IIj was put in a horizontal position. 5 drops of 10% HCl were applied with contact times of 180, 150, 120, 90 and 60 minutes. Also applied were 5 drops of 1 M NaOH with contact times of 180, 120, 60, 30 and 15 minutes.

[0214] Thereafter, the drops were removed with water and the formerly covered sites were visually compared with the uncovered sites. In this context, a rating scale of 0-3 (for each individual point) was applied (0=no attack, 3 maximum degradation of pigments). The points determined were then added up. The results of the chemicals test can be found in table 7.

TABLE-US-00007 TABLE 7 Gassing test Chemicals Example [d/ml] test Example 3 28 d/5 mL 1 Example 4 28 d/3 mL 0 Comparative .sup.5 d/failed 3 example 1

[0215] The advantages of the metal effect pigments of the invention are apparent in the sum total of various properties. The metal effect pigments of the invention have high hiding, very good mechanical and chemical stability, and high gloss and color intensity. The comparative pigment, considered overall, has the properties mentioned only in an unsatisfactory manner.

IIl Scanning Electron Micrographs

[0216] The scanning electron micrographs were obtained using transverse sections of the metal effect pigments of the invention with the Supra 35 scanning electron microscope (from Zeiss). Energy-dispersive x-ray micro-analysis (EDX analysis) was conducted with the EDAX Sapphire instrument, from EDAX.

III APPLICATION EXAMPLES

Application Example 1: Eyeshadow Cream

[0217]

TABLE-US-00008 % by Manufacturer/ INCI name Product name wt. supplier Phase A Microcrystalline Wax TeCero-Wax 1030 4.50 Tromm Wachs K Copernicia Cerifera Cera Carnaubawachs LT 4.50 Tromm Wachs 124 Isohexadecane Isohexadecane 21.00 Ineos Cyclopentasiloxane, Belsil RG 100 8.00 Wacker Dimethicone/ Silicone Elastomer Vinyltrimethylsiloxysilicate Resin Gel Crosspolymer Trimethylsiloxyphenyl Belsil PDM 20 6.00 Wacker Dimethicone Dimethicone Belsil DM 100 14.00 Wacker Caprylic/Capric Miglyol 812 7.00 Sasol Triglyceride Cyclomethicone (and) Tixogel VSP-1438 5.00 BYK Quaternium-90 Bentonite (and) Propylene Carbonate Phase B Metal effect 30.00 pigment from example 1

[0218] The metal effect pigment from example 1 can be used within a range from 5% to 30.0% by weight, based on the total weight of the eyeshadow formulation. Compensation to 100% by weight of the formulation can be effected with isohexadecane.

[0219] Phase A was mixed and heated to 85 C., then phase B was added to phase A while stirring. After dispensing into an appropriate container, the mixture is cooled to room temperature.

Application Example 2: Eyeshadow Compact

[0220]

TABLE-US-00009 % by Manufacturer/ INCI name Product name wt. supplier Phase A Talc Talc Powder 36.00 VWR Bentonite Optigel CK-PC 5.00 BYK Synthetic Synafil S 1050 13.00 ECKART Aluminium Starch Agenaflo OS 9051 10.00 Agrana Magnesium Stearate Magnesium Stearate 6.00 VWR Metal effect 20.00 pigment from example 2 Phase B Cyclomethicone Xiameter PMX-0345 5.00 Dow Corning Octyldodecyl Stearoyl Ceraphyl 847 5.00 Ashland Stearate

[0221] The metal effect pigment from example 2 can be used within a range from 5.0% to 40.0% by weight, based on the total weight of the eyeshadow formulation. Compensation to 100% by weight of the formulation can be effected with talc.

[0222] Phase A was mixed in a high-speed mixer at 2500 rpm for 30 s. Subsequently, phase B was added and the mixture was mixed in the same mixer at 3000 rpm for 60 s. Finally, the powder mixture was pressed into shape by means of an eyeshadow press at 100 bar for 30 seconds.

Application Example 3: Body Powder

[0223]

TABLE-US-00010 % by Manufacturer/ INCI name Product name wt. supplier Phase A Synthetic Fluorphlogopite Synafil S 1050 40.00 ECKART Polypropylene Synafil W 1234 8.00 ECKART Bentonite Optigel CK-PC 10.00 BYK Talc Talc Powder 18.00 VWR Magnesium Stearate Magnesium Stearate 4.00 Applichem Metal effect 20.00 pigment from example 3

[0224] The metal effect pigment from example 3 can be used within a range from 0.2% to 5.0% by weight, based on the total weight of the body powder formulation. Compensation to 100% by weight of the formulation can be effected with Synafil S 1050.

[0225] Phase A was mixed and then the powder was dispensed into a suitable vessel.

Application Example 4: Lipgloss

[0226]

TABLE-US-00011 % by Manufacturer/ INCI name Product name wt. supplier Phase A Hydrogenated Polyisobutene Versagel ME 75.30 Penreco (and) Ethylene/Propylene/ 750 Styrene Copolymer (and) Butylene/Ethylene/Styrene Copolymer Simmondsia Chinensis Jojoba Oil - 2.00 BioChemica (Jojoba) Seed Oil Natural Caprylyl Trimethicone Silcare 7.00 Clariant Silicone 31M50 Stearyl Dimethicone Silcare 3.20 Clariant Silicone 41M65 Hydrogenated Polydecene Dekanex 2004 4.00 IMCD FG Isopropyl Myristate Isopropyl 4.50 VWR Myristate Phase B Metal effect 4.00 pigment from example 1

[0227] The metal effect pigment from example 1 can be used within a range from 0.10% to 8.00% by weight, based on the total weight of the lipgloss formulation. Compensation to 100% by weight of the formulation can be effected with Versagel ME 750.

[0228] Phase A was heated to 85 C., then the pigment from example 1 was added to phase B and stirred until the consistency was homogeneous, and then dispensed into a lipgloss vessel.

Application Example 5: Lipstick

[0229]

TABLE-US-00012 % by Manufacturer/ INCI name Product name wt. supplier Phase A Octyldodecanol Eutanol G 42.5 BASF Candelilla Cera Kahlwax 2039 6.00 Kahl Copernicia Cerifera Kahlwax 2442 6.00 Kahl (Carnauba) Wax Bis-Diglyceryl Softisan 649 10.00 Sasol Polyacyladipate-2 Polyisobutene Rewopal PIB 1000 10.00 Evonik Hydrogenated Polydecene Silkflo 364 NF 5.00 Ineos C10-18 Triglycerides Lipocire A Pellets 5.00 Gattefosse Acacia Decurrens/Jojoba/ Hydracire S 5.00 Gattefosse Sunflower Seed Wax/ Polyglyceryl-3 Esters Tocopheryl Acetate dl-alpha-Tocopheryl 0.50 IMCD Phase B Metal effect 10.00 pigment from example 2

[0230] The metal effect pigment from example 2 can be used within a range from 0.5% to 20.0% by weight, based on the total weight of the lipstick formulation. Compensation to 100% by weight of the formulation can be effected with Eutanol G.

[0231] Phase A was heated to 85 C., then phase B was added to phase A and mixed. Subsequently, this mixture was dispensed into a lipstick mold at a temperature of 75 C.

Application Example 6: Liquid Eyelid Liner

[0232]

TABLE-US-00013 % by Manufacturer/ INCI name Product name wt. supplier Phase A Aqua Water 56.90 Bentonite (and) Xanthan Gum Optigel WX-PC 1.40 Phase B Lecithin Emulmetik 100 0.10 Lucas Meyer Copernicia Cerifera Cera Kahlwax 2442 1.00 Kahl Stearic Acid Stearic Acid 3.50 Lipo Chemicals Hydrogenated Polyisobutene Panalane L14 E 5.00 Ineos Polysorbate 60 Mulsifan CPS 1.50 Zschimmer & 60 Schwarz Phase C Metal effect 4.00 pigment from example 3 Polyurethane-35 Baycusan C 18.00 Bayer 1004 Cosmetics Aqua and Cl 77499 and WorleBase 8.00 Worle Methylpropanediol and AQ 77499/1 Ammonium Acrylates Copolymer and Simethicone and Caprylyl Glycol and Phenylpropanol Sodium Acrylates Copolymer Phenoxyethanol, Euxyl PE9010 0.60 Schlke Ethylhexylglycerin & Mayr

[0233] The metal effect pigment from example 3 can be used within a range from 0.5% to 8.0% by weight, based on the total weight of the eyelid liner formulation. Compensation to 100% by weight of the formulation can be effected with water.

[0234] Optigel WX-PC was dispersed in water of phase A and stirred for 10 minutes. Phase A and phase B were heated separately to 80 C. Thereafter, phase B was added gradually to phase A while stirring. After cooling to 45 C., the ingredients of phase C were added gradually and the mixture was dispensed into a suitable package.

Application Example 7: Mousse

[0235]

TABLE-US-00014 % by Manufacturer/ INCI name Product name wt. supplier Phase A Cyclopentasiloxane Xiameter PMX-0245 8.60 Dow Corning Cyclosiloxane Hydrogenated MC 30 4.00 Sophim Polyisobutene Dimethicone (and) Dow Corning 9041 37.14 Dow Corning Dimethicone Silicone Elastomer Crosspolymer Blend Squalane Squalane 5.74 Impag Isononyl Isononanoate Dermol 99 10.16 Akzo International Hydrogenated Jojoba Oil Jojoba Butter LM 2.15 Desert Whale Hydrogenated Jojoba Oi Jojoba Butter HM 1.00 Desert Whale C30-45 Alkyl Methicone Dow Corning 1.15 Dow Corning (and) C30-45 Olefin AMS-C30 Cosmetic Wax Stearyl Dimethicone Dow Corning 2503 0.47 Dow Corning Cosmetic Wax Cyclopentasiloxane (and) Dow Corning 670 5.00 Dow Corning Polypropylsilsesquioxane Fluid Phase B Dimethicone/Vinyl Dow Corning 9506 16.02 Dow Corning Dimethicone Powder Crosspolymer Silica Dimethyl Covasilic 15 0.17 LCW Silylate Talc Talc Powder 5.00 Sigma-Aldrich Metal effect 3.00 pigment from example 2 Phase D Phenoxyethanol, Euxyl PE 0.40 Schlke Ethylhexylglycerin 9010 & Mayr

[0236] The metal effect pigment from example 2 can be used within a range from 0.1% to 8.0% by weight, based on the total weight of the mousse formulation. Compensation to 100% by weight of the formulation can be effected with Dow Corning 9041 Elastomer.

[0237] Phase A was mixed and heated until everything had melted. Phase B was weighed out separately and mixed with a high-speed mixer at 2400 rpm for 60 s. Half of the molten phase A was added to phase B and the mixture was mixed again in the mixer at 2400 rpm for 30 s. Subsequently, the remaining portion of phase B was likewise added to phase A and the mixture was mixed again at 2400 rpm for 30 s. Lastly, phase C was added to phase AB and the mixture was mixed again in the high-speed mixer at 2400 rpm for 30 s.

[0238] FIG. 1: Detail of a scanning electron micrograph of a transverse section in 50 000-fold magnification (based on Polaroid 545) with a baseline drawn in at the interface of substrate in platelet formcoating, and lines arranged at right angles to the baseline. x marks the points of intersection at the interfaces.

[0239] FIG. 2: Schematic diagram of the spacer layer.

[0240] FIG. 3: Schematic diagram of the position of the spacer layer.