Use of coated metallic luster pigments for pigmenting high molecular weight materials

0001The present invention relates to the use of luster pigments based on aluminum platelets, which are coated with a low-refractive, dielectric layer that does not absorb visible light, for pigmenting plastics or thermoplastics according to claims 1 and 2.

0002In addition, the invention relates to the plastics or thermoplastics according to claim 6, which are pigmented with these gloss pigments.

0003Gloss or effect pigments are used in many areas of technology, for example in automotive paints, in decorative coatings, in plastic coloring, in paints and printing inks and in cosmetics.

0004Their optical effect is based on the directed reflection of light on predominantly flat, parallel, metallic or strongly light-refractive pigment particles. With the viewing angle, the brightness and partly also the color tone change.

0005Coloristically, two borderline cases can be distinguished, the metallic effect and the pearlescent.

0006With metallic effect pigments, such as uncoated or coated aluminum flakes, the specular reflection on the smooth surfaces of the flakes dominates. The lacquers or plastics colored with these pigments therefore show an angle-dependent light-dark effect, also known as a brightness flop. The metallic luster and the excellent hiding power are typical of the metallic effect pigments.

0007Pearlescent pigments, on the other hand, are based on transparent, high-index platelets, such as titanium dioxide-coated mica flakes. After parallel orientation of the platelets in the application medium, multiple reflections of the light rays that also pass through the pigment platelets produce a silky, soft glossy effect, which to a certain extent comes from the depth and is also characteristic of pearls.

0008In general, there is particular interest in the coloring of a wide variety of application media in silver-colored metallic effect pigments with high reflection, in particular high brightness in the vicinity of the gloss angle and thus a pronounced brightness flop.

0009Particularly when coloring plastics, there are additional high demands on the application properties of the pigments. The metallic effect pigments must have a high mechanical stability in order to withstand the shear forces that occur during incorporation into the plastic without being deformed or even broken, which results in reduced metallic gloss and an uneven appearance, and in the case of injection molding application or blow molding also clearer flow lines, would result.

0010In addition, the effect pigments must be easy to align in the plastic, since optimal pigmentation and a homogeneous appearance can only be obtained if all pigment flakes are oriented parallel to the surface. This parallel arrangement is particularly disturbed in the injection molding process, since different, uneven flow fronts form in the mold during the injection molding process. If two flow fronts meet, the pigment platelets straighten up at this point and are then no longer aligned parallel to the surface, which in turn leads to an uneasy appearance with clouds, flow lines and flow seams. In addition, the mechanical stability of the plastic at the flow seams is reduced because the polymer only incompletely melts at the flow line boundaries.

0011In the <patcit id="pcit0001" dnum="WO9935194A"><text>WO-A-99/35194</text></patcit> describes metal effect pigments which have a central reflective aluminum film with a thickness of 40 to 150 nm, preferably of 100 nm, which is coated on both sides with a silicon dioxide or magnesium fluoride film of a thickness of 50 to 200 nm, preferably 100 nm. These pigments are produced in a very complex manner by alternately evaporating a substrate film in a high vacuum with the respective film materials, removing the film from the vapor-deposited multilayer film and comminuting it to pigment particle size. Due to this manufacturing process, the central metal film of these pigments is only coated on the top and bottom of the platelet.

0012The in the <patcit id="pcit0002" dnum="WO9935194A"><text>WO-A-99/35194</text></patcit> The pigments disclosed are said to show high reflection and mechanical stability. Although the mechanical stability of the multilayer pigment particles is increased compared to pigment particles based on the uncoated aluminum film, the reflection, as was also to be expected for the person skilled in the art, decreases significantly due to the coating of the metal film. The actual reduction in reflection exceeds that in the<patcit id="pcit0003" dnum="WO9935194A"><text>WO-A-99/35194</text></patcit> calculated reduction.

0013According to the <patcit id="pcit0004" dnum="JP62096565A"><text>JP-A-1987/96565</text></patcit> and <patcit id="pcit0005" dnum="JP62096566A"><text>JP-A-1987/96566</text></patcit> Flow line-free plastic coloring with a high metallic luster can be obtained by using coarse-particle, uncoated aluminum flakes which have large flake diameters and in particular also flake thicknesses. Although these pigment platelets are mechanically stable, due to their coarseness they often lead to undesirable glitter effects ("sparkling"), show only a low brightness flop and have less hiding power than finely divided pigments.

0014The invention was based on the object of providing silver-colored metallic effect pigments which have high brightness in the vicinity of the glancing angle and thus a pronounced brightness flop and, moreover, also show advantageous mechanical properties, in particular also when coloring plastics.

0015Accordingly, the use of gloss pigments based on aluminum platelets, which are coated with a low-refractive, dielectric layer that does not absorb visible light, has been found for pigmenting plastics or thermoplastics.

0016Last but not least, plastics and thermoplastics were also found that are pigmented with these glossy pigments.

0017The gloss pigments to be used according to the invention are based on aluminum flakes which are provided on all side surfaces with a colorless, dielectric coating. This coating has a low refractive index, ie it generally has a refractive index n of &lt;1.8.

0018The thickness of the dielectric layer is usually 100 to 800 nm, preferably 250 to 450 nm and particularly preferably 300 to 400 nm.

0019Preferred substrates are aluminum flakes, which can be produced in a simple manner by punching them out of aluminum foil or using conventional atomization and grinding techniques. Commercial products can be used.

0020The size of the aluminum plate is not critical per se and can be tailored to the desired optical effect. As a rule, the aluminum plates have medium diameters (i.e.₅₀-Value) of about 5 to 200 microns, especially from 10 to 50 microns, and thicknesses of about 0.1 to 5 microns, especially from 0.1 to 0.3 microns. Their specific free surface area (BET) is generally 0.1 to 8 m²/G.

0021For the low refractive index coating of the luster pigments to be used according to the invention, all colorless materials that can be applied in a film-like and permanent manner to the aluminum flakes come into consideration. In addition, these materials should meet the requirements for use, ie they must have the required fastness properties, in particular also thermostabilities. Examples of such materials include silicon dioxide, silicon oxide hydrate, aluminum oxide, aluminum oxide hydrate, magnesium fluoride and aluminum phosphate. Silicon dioxide, silicon oxide hydrate and mixtures thereof are particularly preferred.

0022Such gloss pigments are, for example, from the <patcit id="pcit0006" dnum="EP708154A"><text>EP-A-708 154</text></patcit> known as intermediates for the goniochromatic gloss pigments described there, which have at least one further selectively absorbing, high-index coating. They are advantageously prepared wet-chemically by hydrolytic decomposition of organic silicon compounds in which the organic radicals are bonded to the silicon atom via oxygen atoms, especially alkoxysilanes, in the presence of an organic solvent in which the silicon compounds are soluble, and subsequent drying.

0023Their manufacture can also be done according to the <patcit id="pcit0007" dnum="EP668329A"><text>EP-A-668 329</text></patcit> The described CVD (chemical vapor deposition) process is carried out by decomposing at least one volatile silane containing alkanoyloxy radical in the presence of water vapor and / or oxygen and the moving aluminum plate. However, the wet chemical coating is preferred.

0024If desired, the gloss pigments to be used according to the invention can be provided with an additional colorless outer layer of a surface-modifying agent to increase their compatibility with the plastics or thermoplastics to be pigmented. Suitable for this purpose are, for example, alkoxyalkylsilanes whose alkyl radicals are functionalized at the end.

0025Surprisingly, the luster pigments to be used according to the invention show a significantly higher reflection than the uncoated aluminum pigments when used. The reflection in the visible region of the electromagnetic spectrum, for example in polypropylene, is generally increased by about 30 to 40%. This corresponds to an increase in brightness L * of approximately 10 to 15 points, measured 5 ° outside the gloss angle.

0026The gloss pigments to be used according to the invention are not only particularly bright and therefore also particularly brilliant close to the gloss angle, they are also distinguished by a pronounced brightness flop.

0027In addition, they can be excellently incorporated into plastics, with significantly reduced flow line formation being observed.

0028Plastics or thermoplastics can be pigmented with the luster pigments to be used according to the invention.

0029Both thermoplastics and thermosets can be used. Examples are: Polyethylene (PE), polypropylene (PP), polyisobutene (PIB), polyvinyl chloride (PVC), polyvinylidene difluoride (PVDF), polycarbonate (PC), polycarbonate-polyester blends, polyethylene terephthalate (PET), polyethylene naphthenate (PEN), polybutylene terephthalate (PBT) , Polystyrene (PS), acrylate-butadiene-styrene copolymers (ABS), styrene-acrylonitrile copolymers (SAN), polymethyl (meth) acrylate (PM (M) A), polybutyl (meth) acrylate (PB (M) A ), Polyamides, such as PA 6, PA 6.6 and PA 12, polyethers, polyphenylene ethers, Polyether sulfones, polyether ketones, polyphenylene sulfides, polyimides, polyetherimides, polyesterimides, polyoxymethylene and polyurethanes (PU, TPU). Polymerizable casting resins based on styrene, acrylate or polyester, post-curing polycondensation resins based on melamine or epoxy, and PVC and PUR coating pastes, which are used, for example, for textile coatings, may also be mentioned explicitly.

Examples

A) Production of gloss pigments used according to the invention

Example 1A

0030In one in a 1 m³Mixing tank of 480 kg of ethanol and 4.4 kg of tetraethoxysilane, 50 kg of aluminum pigment paste (average platelet diameter d₅₀-Value 17 µm, platelet thickness approx. 0.14 µm; Alpate® NS 7670, from Toyal Europe; Solids content 65 wt .-%) dispersed with stirring in 1.5 h. After adding initially 142 kg of water and then 14.3 kg of a 25% strength by weight aqueous ammonia solution, the suspension was slowly heated to 60.degree. From a temperature of 55 ° C, separate metering devices were used simultaneously with the metering of (1) 3.6 kg / h tetraethoxysilane, (2) 0.94 kg / h ethanol and (3) 0.86 kg / h 2.5 wt .-% aqueous ammonia solution started.

0031After the addition of 306 kg of tetraethoxysilane (85 h coating time), the doses were stopped and the mixture was stirred for a further 5 h. After the suspension had cooled to room temperature, the coated aluminum pigment was filtered off, washed first with ethanol and then with water, then distributed on metal sheets and dried at 100 ° C. in a drying cabinet.

0032There were 118 kg of light silver SiO₂-coated aluminum pigment (SiO₂Content 69% by weight, layer thickness of SiO₂Coating 340 nm) obtained.

Example 2A

0033The procedure was analogous to Example 1A, but the coating time was only 44 h, which corresponds to an addition of 158.5 kg of tetraethoxysilane.

003479 kg of light silver SiO₂-coated aluminum pigment (SiO₂Content 59% by weight, layer thickness of SiO₂Coating 230 nm) obtained.

Example 3A

0035The procedure was analogous to Example 1A, but the coating time was only 20 h, which corresponds to an addition of 72 kg of tetraethoxysilane.

0036There were 54 kg of light silver SiO₂-coated aluminum pigment (SiO₂Content 41% by weight, layer thickness of SiO₂-Coating 109 nm) obtained.

Example 4A

0037The procedure was analogous to Example 1A, but the coating time was only 13 hours, which corresponds to an addition of 46.8 kg of tetraethoxysilane.

0038There were 47 kg of light silver SiO₂-coated aluminum pigment (SiO₂Content 32% by weight, layer thickness of SiO₂Coating 75 nm) obtained.

Example 5A

0039To a suspension of 150 g aluminum pigment paste (medium platelet diameter d₅₀-Value 15 µm, platelet thickness approx. 0.13 µm; Alpate F 795, from Toyal Europe; Solids content 70% by weight) in 1.6 l of ethanol, 16.4 ml of tetraethoxysilane, 450 ml of water and 40 g of 25% by weight aqueous ammonia solution were added in succession with vigorous stirring. After heating to 60 ° C., (1) 40 ml / h tetraethoxysilane, (2) 10 ml / h 2.5% by weight aqueous ammonia solution and (3) 15 ml / h ethanol while stirring and keeping the temperature constant metered in separately at 60 ° C.

0040After adding 951 ml of tetraethoxysilane (coating time 23.8 h), the doses were stopped and the mixture was stirred for 1 h. After cooling to room temperature, the coated aluminum pigment was filtered off, washed with ethanol and dried at 100 ° C. in vacuo.

0041364 g of light silver SiO₂-coated aluminum pigment (SiO₂Content 71% by weight, layer thickness of SiO₂Coating 389 nm) obtained.

Example 6A

0042The procedure was analogous to Example 5A, but a total of 723 ml of tetraethoxysilane were used.

0043There were 303 g of light silver SiO₂-coated aluminum pigment (SiO₂Content 64% by weight, layer thickness of SiO₂Coating 282 nm) obtained.

Example 7A

0044The procedure was analogous to Example 5A, but a total of 334 ml of tetraethoxysilane were used.

0045190 g of light silver SiO₂-coated aluminum pigment (SiO₂Content 46% by weight, layer thickness of SiO₂Coating 135 nm) obtained.

Example 8A

0046The procedure was analogous to Example 5A, but a total of 195 ml of tetraethoxysilane was used.

0047154 g of light silver SiO₂-coated aluminum pigment (SiO₂Content 34% by weight, layer thickness of SiO₂-Coating 82 nm) obtained.

Example 9A

0048The procedure was analogous to Example 5A, but a total of 119 ml of tetraethoxysilane were used.

0049133 g of light silver SiO₂-coated aluminum pigment (SiO₂Content 22% by weight, layer thickness of SiO₂Coating 50 nm) obtained.

Example 10A

0050To a suspension of 350 g aluminum pigment paste (average platelet diameter d₅₀-Value 75 µm, platelet thickness approx. 0.5 µm; Stapa Metallux® 211, Eckart-Werke; Solids content 70% by weight) in 1.3 l of ethanol, 14.2 ml of tetraethoxysilane, 400 ml of water and 40 g of 25% by weight aqueous ammonia solution were added in succession with vigorous stirring. After heating to 60 ° C, (1) 25 ml / h tetraethoxysilane, (2) 10 ml / h 2.5% by weight aqueous ammonia solution and (3) 10 ml / h ethanol while stirring and keeping the temperature at 60 ° C metered.

0051After the addition of 602 ml of tetraethoxysilane (coating time 23.5 h), the doses were stopped and stirring was continued for 1 h. After cooling to room temperature, the coated aluminum pigment was filtered off, washed with ethanol and dried at 100 ° C. in vacuo.

0052There were 415 g of light silver SiO₂-coated aluminum pigment (SiO₂Content 39.1% by weight, layer thickness of the SiO₂Coating 335 nm) obtained.

Example 11 A

0053The procedure was analogous to Example 10A, but a total of 664 ml of tetraethoxysilane were used.

0054There were 432 g of light silver SiO₂-coated aluminum pigment (SiO₂Content 41.9% by weight, layer thickness of the SiO₂Coating 383 nm) obtained.

B) Use of the gloss pigments produced for pigmenting plastics

0055Plastic flakes were pigmented with the luster pigments prepared in Examples 1A to 11A and then measured colorimetrically. The numbering of the application examples corresponds to the numbering of the production examples, the application examples are identified by a B after them. In other words, in application example 1B, the luster pigment from preparation example 1A was used, etc.

0056For comparison, plastic platelets were also pigmented with the respective uncoated aluminum pigments.

0057To determine their colorimetric data, the pigmented plastic plates were measured using measurement methods I and II. The data obtained were converted into the color values ​​L *, a * and b * according to CIE (standard illuminant D65, standard viewer 10 °).

Measurement method I

0058The pigmented plastic plates were measured with a multiflash goniospectral photometer (from Optronic, Berlin) depending on the angle. The illumination angle was kept constant at 45 °, while the difference angle between the measurement angle and the gloss angle was changed.

0059A white tile was used as the standard for measuring the brightness.

0060A metal effect value ME was defined as follows to characterize the brightness flop of the platelets when changing from top view to oblique view: <maths id="math0001"><math display="block"><mi>ME</mi><mo mathvariant="normal">=</mo><mfrac><mfenced><mi mathvariant="normal">L</mi><mo>⁢</mo><msub><mo mathvariant="normal">*</mo><mn mathvariant="normal">25</mn></msub><mo mathvariant="normal">-</mo><mi mathvariant="normal">L</mi><mo>⁢</mo><msub><mo mathvariant="normal">*</mo><mn mathvariant="normal">75</mn></msub></mfenced><mrow><mi mathvariant="normal">L</mi><mo>⁢</mo><msub><mo mathvariant="normal">*</mo><mn mathvariant="normal">75</mn></msub></mrow></mfrac></math><img file="EP1618147B2_D0001.tif" /></maths>

0061Mean:<ul id="ul0001" list-style="none" compact="compact"><li>L *₂₅: Brightness of the plate with a difference to the gloss angle of 25 °</li><li>L *₇₅: Brightness of the plate with a difference to the gloss angle of 75 °</li></ul>

0062The larger the ME values, the more pronounced the brightness flop.

0063The results obtained with measurement method I are summarized in Tables 1, 3 and 5.

Measurement method II

0064The pigmented plastic plates were measured with a goniospectral photometer GKR 311 (from Zeiss) depending on the angle. The difference angle between measuring angle and gloss angle was kept constant at 5 °, while the illumination angle was changed in 5 ° steps.

0065The plastic plate pigmented with the respective uncoated aluminum pigment, to which brightness 100 was assigned, was used as standard.

0066The results obtained with measurement method II are summarized in Tables 2, 4 and 6. The angle specifications relate to the sample horizontal.

Examples 1B to 4B

0067The SiO₂Coated aluminum pigments from Examples 1A to 4A were each dispersed with a dissolver at 1400 rpm for 30 minutes in a 20% by weight solution of polymethyl methacrylate (PMMA; Lucryl®, BASF) in acetone. The suspension obtained in each case was injected into a fluidized bed and the acetone was evaporated.

0068The 5% by weight pigmented PMMA granulate obtained was diluted to a pigment concentration of 2% by weight by mixing with further PMMA and cast as a color layer in a three-layer film (1.2 m wide, endless).

0069The three-layer film had the following structure:<ul id="ul0002" list-style="none" compact="compact"><li>50 µm clear top layer (PMMA)</li><li>200 µm color layer (PMMA + pigment)</li><li>600 µm lower layer (acrylonitrile / styrene / acrylic ester copolymer, ASA; Luran® S, BASF)</li></ul>

0070The results obtained in each case in the colorimetric measurement according to measurement methods I and II are summarized in Tables 1 and 2, respectively. For comparison, the results obtained with the uncoated aluminum pigment from Example 1A are listed in Table 1 (Example V1). In Table 2:<ul id="ul0003" list-style="none" compact="compact"><li>BW: Illumination angle</li><li>MW: measuring angle</li></ul><tables id="tabl0001" num="0001"><table frame="all"><title>Table 1</title><tgroup cols="4"><colspec colnum="1" colname="col1" colwidth="17mm" align="center" /><colspec colnum="2" colname="col2" colwidth="12mm" align="center" /><colspec colnum="3" colname="col3" colwidth="12mm" align="center" /><colspec colnum="4" colname="col4" colwidth="12mm" /><thead><row><entry valign="top">example</entry><entry valign="top">L *₂₅</entry><entry valign="top">L *₇₅</entry><entry align="center" valign="top">ME</entry></row></thead><tbody><row><entry>1B</entry><entry>81,4</entry><entry>30,7</entry><entry align="center">1,65</entry></row><row><entry>2 B</entry><entry>94,2</entry><entry>29,7</entry><entry align="center">2,17</entry></row><row><entry>3B</entry><entry>93,4</entry><entry>28,9</entry><entry align="center">2,23</entry></row><row><entry>4B</entry><entry>79,8</entry><entry>27,5</entry><entry align="center">1,91</entry></row><row><entry>V1</entry><entry>74,1</entry><entry>40,2</entry><entry align="center">0,84</entry></row></tbody></tgroup></table></tables><tables id="tabl0002" num="0002"><table frame="all"><title>Table 2</title><tgroup cols="6" align="center"><colspec colnum="1" colname="col1" colwidth="14mm" /><colspec colnum="2" colname="col2" colwidth="15mm" /><colspec colnum="3" colname="col3" colwidth="22mm" /><colspec colnum="4" colname="col4" colwidth="22mm" /><colspec colnum="5" colname="col5" colwidth="22mm" /><colspec colnum="6" colname="col6" colwidth="22mm" /><thead><row><entry valign="top">BW [°]</entry><entry valign="top">MW [°]</entry><entry valign="top">L * (e.g. 1B)</entry><entry valign="top">L * (Ex.2B)</entry><entry valign="top">L * (Ex.3B)</entry><entry valign="top">L * (Ex.4B)</entry></row></thead><tbody><row><entry>75</entry><entry>100</entry><entry>112,1</entry><entry>113,0</entry><entry>119,7</entry><entry>132,9</entry></row><row><entry>70</entry><entry>105</entry><entry>111,5</entry><entry>112,7</entry><entry>119,2</entry><entry>132,4</entry></row><row><entry>65</entry><entry>110</entry><entry>111,2</entry><entry>112,4</entry><entry>118,9</entry><entry>132,1</entry></row><row><entry>60</entry><entry>115</entry><entry>110,8</entry><entry>112,1</entry><entry>118,8</entry><entry>131,7</entry></row><row><entry>55</entry><entry>120</entry><entry>110,6</entry><entry>112,4</entry><entry>118,7</entry><entry>131,4</entry></row><row><entry>50</entry><entry>125</entry><entry>110,2</entry><entry>112,2</entry><entry>118,6</entry><entry>130,9</entry></row><row><entry>45</entry><entry>130</entry><entry>110,0</entry><entry>112,3</entry><entry>118,6</entry><entry>130,5</entry></row><row><entry>40</entry><entry>135</entry><entry>109,4</entry><entry>112,1</entry><entry>118,4</entry><entry>129,6</entry></row><row><entry>35</entry><entry>140</entry><entry>108,9</entry><entry>112,1</entry><entry>118,3</entry><entry>128,6</entry></row><row><entry>30</entry><entry>145</entry><entry>108,0</entry><entry>111,8</entry><entry>117,5</entry><entry>126,9</entry></row><row><entry>25</entry><entry>150</entry><entry>106,5</entry><entry>110,9</entry><entry>116,0</entry><entry>123,9</entry></row></tbody></tgroup></table></tables>

Examples 5B to 9B

0071The SiO₂-coated aluminum pigments from Examples 5A to 9A were each pre-extruded in glass-clear polypropylene (Metocene® X 50081, Basell) in a concentration of 1% by weight and processed into 6 cm × 4.4 cm × 0.2 cm spray platelets.

0072The results obtained in each case in the colorimetric measurement according to measurement methods I and II are summarized in Tables 3 and 4, respectively. For comparison, the results obtained with the uncoated aluminum pigment from Example 5A are listed in Table 3 (Example V2). In Table 4:<ul id="ul0004" list-style="none" compact="compact"><li>BW: Illumination angle</li><li>MW: measuring angle</li></ul><tables id="tabl0003" num="0003"><table frame="all"><title>Table 3</title><tgroup cols="4" align="center"><colspec colnum="1" colname="col1" colwidth="17mm" /><colspec colnum="2" colname="col2" colwidth="13mm" /><colspec colnum="3" colname="col3" colwidth="12mm" /><colspec colnum="4" colname="col4" colwidth="12mm" /><thead><row><entry valign="top">example</entry><entry valign="top">L *₂₅</entry><entry valign="top">L *₇₅</entry><entry valign="top">ME</entry></row></thead><tbody><row><entry>5B</entry><entry>89,5</entry><entry>29,4</entry><entry>2,04</entry></row><row><entry>6B</entry><entry>95,0</entry><entry>29,0</entry><entry>2,28</entry></row><row><entry>7B</entry><entry>104,3</entry><entry>30,6</entry><entry>2,41</entry></row><row><entry>8B</entry><entry>105,2</entry><entry>30,4</entry><entry>2,46</entry></row><row><entry>9B</entry><entry>105,6</entry><entry>32,1</entry><entry>2,29</entry></row><row><entry>V2</entry><entry>104,6</entry><entry>36,6</entry><entry>1,86</entry></row></tbody></tgroup></table></tables><tables id="tabl0004" num="0004"><table frame="all"><title>Table 4</title><tgroup cols="7" align="center"><colspec colnum="1" colname="col1" colwidth="14mm" /><colspec colnum="2" colname="col2" colwidth="15mm" /><colspec colnum="3" colname="col3" colwidth="22mm" /><colspec colnum="4" colname="col4" colwidth="22mm" /><colspec colnum="5" colname="col5" colwidth="22mm" /><colspec colnum="6" colname="col6" colwidth="22mm" /><colspec colnum="7" colname="col7" colwidth="22mm" /><thead><row><entry valign="top">BW [°]</entry><entry valign="top">MW [°]</entry><entry valign="top">L * (Ex. 5B)</entry><entry valign="top">L * (e.g. 6B)</entry><entry valign="top">L * (Example 7B)</entry><entry valign="top">L * (e.g. 8B)</entry><entry valign="top">L * (Ex. 9B)</entry></row></thead><tbody><row><entry>75</entry><entry>100</entry><entry>107,1</entry><entry>110,9</entry><entry>113,3</entry><entry>116,7</entry><entry>112,0</entry></row><row><entry>70</entry><entry>105</entry><entry>106,7</entry><entry>110,9</entry><entry>112,6</entry><entry>115,6</entry><entry>111,5</entry></row><row><entry>65</entry><entry>110</entry><entry>107,0</entry><entry>111,0</entry><entry>112,5</entry><entry>115,4</entry><entry>111,3</entry></row><row><entry>60</entry><entry>115</entry><entry>106,8</entry><entry>110,8</entry><entry>112,0</entry><entry>114,9</entry><entry>110,7</entry></row><row><entry>55</entry><entry>120</entry><entry>106,4</entry><entry>110,6</entry><entry>111,5</entry><entry>114,3</entry><entry>110,1</entry></row><row><entry>50</entry><entry>125</entry><entry>106,5</entry><entry>110,3</entry><entry>111,3</entry><entry>114,0</entry><entry>109,9</entry></row><row><entry>45</entry><entry>130</entry><entry>106,8</entry><entry>110,1</entry><entry>111,3</entry><entry>114,0</entry><entry>109,7</entry></row><row><entry>40</entry><entry>135</entry><entry>106,4</entry><entry>109,0</entry><entry>110,6</entry><entry>113,2</entry><entry>109,0</entry></row><row><entry>35</entry><entry>140</entry><entry>105,8</entry><entry>108,2</entry><entry>109,5</entry><entry>112,1</entry><entry>108,0</entry></row><row><entry>30</entry><entry>145</entry><entry>104,9</entry><entry>106,2</entry><entry>107,6</entry><entry>110,0</entry><entry>106,3</entry></row><row><entry>25</entry><entry>150</entry><entry>103,5</entry><entry>104,0</entry><entry>105,4</entry><entry>107,7</entry><entry>103,1</entry></row></tbody></tgroup></table></tables>

Examples 10B and 11B

0073The SiO₂Coated aluminum pigments from Examples 10A and 11A were each pre-extruded in glass-clear polypropylene (Metocene X 50081, Basell) in a concentration of 2% by weight and processed into 6 cm X 4.4 cm X 0.2 cm spray platelets.

0074The results obtained in each case in the colorimetric measurement according to measurement methods I and II are summarized in Tables 4 and 5, respectively. For comparison, the results obtained with the uncoated aluminum pigment from Example 10A are listed in Table 5 (Example V3). In Table 6 mean:<ul id="ul0005" list-style="none" compact="compact"><li>BW: Illumination angle</li><li>MW: measuring angle</li></ul><tables id="tabl0005" num="0005"><table frame="all"><title>Table 5</title><tgroup cols="4" align="center"><colspec colnum="1" colname="col1" colwidth="17mm" /><colspec colnum="2" colname="col2" colwidth="12mm" /><colspec colnum="3" colname="col3" colwidth="12mm" /><colspec colnum="4" colname="col4" colwidth="12mm" /><thead><row><entry valign="top">example</entry><entry valign="top">L *₂₅</entry><entry valign="top">L *₇₅</entry><entry valign="top">ME</entry></row></thead><tbody><row><entry>10B</entry><entry>79,2</entry><entry>35,1</entry><entry>1,26</entry></row><row><entry>11B</entry><entry>79,7</entry><entry>35,2</entry><entry>1,26</entry></row><row><entry>V3</entry><entry>76,3</entry><entry>38,1</entry><entry>1,00</entry></row></tbody></tgroup></table></tables><tables id="tabl0006" num="0006"><table frame="all"><title>Table 6</title><tgroup cols="4" align="center"><colspec colnum="1" colname="col1" colwidth="14mm" /><colspec colnum="2" colname="col2" colwidth="15mm" /><colspec colnum="3" colname="col3" colwidth="24mm" /><colspec colnum="4" colname="col4" colwidth="24mm" /><thead><row><entry valign="top">BW [°]</entry><entry valign="top">MW [°]</entry><entry valign="top">L * (e.g. 10B)</entry><entry valign="top">L * (Ex. 11B)</entry></row></thead><tbody><row><entry>75</entry><entry>100</entry><entry>113,3</entry><entry>115,5</entry></row><row><entry>70</entry><entry>105</entry><entry>113,2</entry><entry>115,5</entry></row><row><entry>65</entry><entry>110</entry><entry>113,0</entry><entry>115,4</entry></row><row><entry>60</entry><entry>115</entry><entry>113,1</entry><entry>115,2</entry></row><row><entry>55</entry><entry>120</entry><entry>113,0</entry><entry>115,2</entry></row><row><entry>50</entry><entry>125</entry><entry>112,0</entry><entry>114,1</entry></row><row><entry>45</entry><entry>130</entry><entry>110,7</entry><entry>112,9</entry></row><row><entry>40</entry><entry>135</entry><entry>110,1</entry><entry>112,1</entry></row><row><entry>35</entry><entry>140</entry><entry>106,1</entry><entry>108,0</entry></row><row><entry>30</entry><entry>145</entry><entry>102,9</entry><entry>105,0</entry></row><row><entry>25</entry><entry>150</entry><entry>100,4</entry><entry>103,7</entry></row></tbody></tgroup></table></tables>