Titanium dioxide pigments with post-coloring treatment

Abstract

The present invention relates to color pigment particles, a method for obtaining said color pigment particles, and compositions comprising said particles. Furthermore, the present invention relates to the use of said color pigment particles.

Description

[Technical field]

[0001] The present invention relates to color pigment particles, to a method for obtaining said color pigment particles, and to compositions comprising said particles.Finally, the present invention relates to the use of the color pigment particles in various applications. [Background technology]

[0002] In addition to its use as a white pigment in luxury applications, titanium dioxide is also used in colorful applications, where it scatters visible light, thereby providing the desired hiding power that colored pigments cannot provide.

[0003] Depending on the end use of the colored titanium dioxide pigment particles, it is generally provided in two forms: first, a base coat of titanium dioxide is applied, over which an additional coat of coloring components is applied (this technique is used, for example, in premium applications such as automotive coatings); or, the titanium dioxide is mixed with the coloring components and the resulting mixture is applied as a single coating.

[0004] However, both approaches have some drawbacks: the size of the aggregates is too large, so the disintegration of the aggregated coloring components is essential; moreover, the coloring components must be reamed so that they are ideally dispersed in the composition; due to the nature of most of these components, this requires a large input of energy and is also time consuming.

[0005] Furthermore, when a single coating containing a mixture of titanium dioxide and coloring components is applied, the coloring components located away from the surface of the coating may be covered by the titanium dioxide particles, resulting in a loss of coloring effect, which in turn requires the incorporation of more color pigment particles to achieve the desired coloring effect, resulting in higher costs.

[0006] Therefore, there is a need in the art for color pigment particles that are easy to manufacture and handle, provide effective coloring effects, and are cost-effective. It is also desirable to provide color particles that can be available in a wide range of colors. Therefore, a variety of coloring components should be applicable. Summary of the Invention [Problem to be solved by the invention]

[0007] The object of the present invention is to provide color pigment particles that are easy to manufacture and handle, provide effective coloring effects, and are also cost-effective. It is also desirable to provide color particles that can adopt a wide range of colors. Therefore, various coloring components should be applicable. [Means for solving the problem]

[0008] This objective is achieved by the colored pigment particles, the method for obtaining same, compositions comprising said particles, as well as the use of the pigment particles described herein.

[0009] Surprisingly, it has been found that color pigment particles consisting of a titanium dioxide-based pigment and at least one layer, characterized in that at least one layer is modified with a coloring component, are easy to manufacture and handle, provide effective coloring effects, and are also cost-effective. Since many coloring components can be applied, the color pigment particles according to the invention are not limited to a specific color, but can provide many different colors. Since at least one layer is modified with a coloring component, there is no need to incorporate the coloring component into compositions such as lacquers, paints, etc. in an additional step (which is very burdensome, since this step requires a lot of time and energy). In particular, the incorporation of the pigment particles according to the invention is less burdensome. Furthermore, the amount of expensive coloring components can be reduced by using the coloring components more efficiently.

[0010] Thus, in a first aspect, the present invention relates to a colour pigment particle comprising a titanium dioxide based pigment and at least one layer, at least one layer being modified with a colouring component.

[0011] In a second aspect, the present invention provides a method for producing a composition comprising the steps of: a) providing an aqueous suspension of a titanium dioxide based pigment; b) adding a layer precursor to the suspension; c) adding a color component to the suspension; d) forming a layer on the titanium dioxide-based pigment from the layer precursor modified with the coloring component to obtain colored pigment particles; The present invention relates to a method for obtaining colored pigment particles, comprising:

[0012] In a further aspect, the present invention relates to a composition comprising the color pigment particles claimed herein.

[0013] In another aspect, the present invention relates to a composition comprising the colored pigment particles claimed herein.

[0014] Finally, the present invention relates to the use of the colored pigment particles as claimed herein for coloring layers, lacquers, paints, plastics, papers or inks.

[0015] Further advantageous embodiments of the invention are set forth in the dependent claims. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1 shows the CIELAB results for Examples 1a-1d. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] These and other aspects, features and advantages of the present invention will become apparent to those skilled in the art upon review of the following detailed description and claims. Each feature from one aspect of the present invention can be used in any other aspect of the present invention. Numerical ranges described in the format "from x to y" include the stated values ​​and values ​​within the respective measurement precision known to those skilled in the art. When several preferred numerical ranges are described in this format, it goes without saying that all ranges formed by combining the various endpoints are also included.

[0018] The color pigment particles according to the present invention are characterized in that they comprise a titanium dioxide-based pigment and at least one layer, at least one layer being modified with a coloring component. As used herein, "titanium dioxide-based pigment" refers to a titanium dioxide-based pigment obtained by the sulfate or chloride process and optionally milled. Furthermore, said pigment can be present in a rutile, anatase or brookite crystal structure, usually in a rutile or anatase crystal structure. Rutile is particularly suitable since it has a lower photocatalytic activity compared to anatase. Preferably, said titanium dioxide-based pigment consists of at least 98% by weight, preferably at least 99% by weight, of rutile, based on the total weight of said particle. The particles further comprise at least one layer. Precursors and techniques for forming such at least one layer are known in the art. At least one layer is modified with a coloring component. Any coloring component known in the art that imparts a color, preferably a color different from white or black, can be used.

[0019] Within the scope of the present invention, the titanium dioxide-based pigments have a primary size such that they ideally rapidly scatter visible light. The particle size is the mass-related median d50 (hereinafter d50) between 200 nm and 400 nm as measured by disc centrifugation.

[0020] In a preferred embodiment, the pigment particles comprise further layers.

[0021] In yet another preferred embodiment, the at least one layer is located between the titanium dioxide-based pigment and the further layer. In another preferred embodiment, the further layer is located between the titanium dioxide-based pigment and the at least one layer.

[0022] The at least one layer and the further layer are preferably independently selected from the group consisting of silicon dioxide, aluminum oxide, zirconium dioxide, manganese oxide, cerium oxide, titanium dioxide, sulfate or phosphate-based inorganic compounds or mixtures thereof. As the phosphate-based inorganic compound, aluminum phosphate is preferred. As the sulfate-based inorganic compound, cerium sulfate is preferred. Even more preferably, the at least one layer and the further layer are independently selected from the group consisting of silicon dioxide, aluminum oxide, zirconium dioxide, manganese oxide, cerium oxide, titanium dioxide, sulfate and phosphate-based inorganic compounds or mixtures thereof. It should be noted that the oxides also include the respective hydroxides, oxyhydroxides and the respective water-containing phases.

[0023] Furthermore, the color pigment particle preferably comprises a final layer comprising a silicon-based organic compound. The "final layer" as defined herein is the outermost layer of the color pigment particle. Such a compound can be selected from siloxanes, silanes and alcohols, such as commercially available Tegomer DA 640, trimethylolpropane (TMP), octyltrichlorosilane (OCTCS), octyltriethoxysilane (OCTEO) or etidronic acid.

[0024] The coloring component is preferably Co. 3 (PO 4 ) 3 , N.H. 4 MnP 2 O 7 , Fe 4 [Fe(CN) 6 ] 3 , PbCrO 4 , BaMnO 4 , BaCrO 4 , Fe(OH) 3 , Fe(OH) 2、Cu(OH) 2 、Ni(OH) 2 、Co(OH) 2 、Cr(OH) 3 、Mn(OH) 2 、V(OH) 5 、Bi(OH) 3 、Ce(OH) 3 、FeO、Fe 2 A 3 ,With 2 O、CuO、CoO、CrO、Cr 2 A 3 、CrO 2 、MnO、Mn 2 A 3 、Mn 3 A 4 ,VO,V 2 A 3 、VO 2 、V 2 A 5 、Bi 2 A 3 、Bi 2 A 5 、At 2 A 3 、La(OH) 3 、CeO 2 ,What 2 A 3 ,What 3 A 4 、Ce(OH) 3 、Ce(OH) 4 、Pr 6 A 11 、Pr(OH) 3 ,Us 2 A 3 、Nd(OH) 3 ,P.m 2 A 3 、Pm(OH) 3 、Sm 2 A 3 、Sm(OH) 3 ,I 2 A 3 、I(OH) 3 、Gd 2 A 3 、Gd 2 (OH) 3 、Tb 4 A 7 、Tb(OH) 3, Dy 2 O 3 , Dy(OH) 3 , Ho 2 O 3 , Ho(OH) 3 , Er 2 O 3 , Er(OH) 3 , Tm 2 O 3 , Tm(OH) 3 , Yb 2 O 3 , Yb(OH) 3 , Lu 2 O 3 , and Lu(OH) 3 is selected from the group consisting of:

[0025] More preferably, the coloring component is Co. 3 (PO 4 ) 3 , N.H. 4 MnP 2 O 7 , Fe 4 [Fe(CN) 6 ] 3 , PbCrO 4 , BaMnO 4 and BaCrO 4 is selected from the group consisting of:

[0026] In a preferred embodiment, the further layer of color pigment particles is also modified with a coloring component.

[0027] In yet another embodiment, the at least one layer and the further layer are modified with the same coloring component, or the at least one layer and the further layer are modified with different coloring components.

[0028] The color pigment particles preferably comprise from 0.5% to 6% by weight, more preferably from 0.75% to 3% by weight, and even more preferably 1% to 2% by weight of the color component based on the total weight of the color pigment particles.

[0029] The present invention further comprises the steps of: a) providing an aqueous suspension of a titanium dioxide based pigment; b) adding a layer precursor to the suspension; c) adding a color component to the suspension; and d) forming a layer on the titanium dioxide-based pigment from the layer precursor modified with the coloring component to obtain colored pigment particles; The present invention relates to a method for obtaining colored pigment particles, comprising the steps of:

[0030] The method steps described herein are carried out in the following order: a), b), c), and d). However, the method can also be carried out in the following order: a), c), b), and d). Steps b) and c) can be carried out simultaneously. The layer, when used in connection with the method according to the invention, can be at least one layer or a further layer. In one embodiment, the titanium dioxide-based pigment provided in step a) comprises at least one layer and a further layer is formed in step d).

[0031] Any known silicon dioxide precursors, such as sodium silicate, potassium silicate and lithium silicate, can be used to form the silicon dioxide layer. Preferably, sodium silicate is used. The silicon dioxide layer can be formed by known methods and techniques. The precursor is preferably added under stirring and, if necessary, at elevated temperature. The precursor can be added to the suspension over a period of 5 to 60 minutes, preferably 30 minutes. The formed silicon dioxide layer of the present invention includes not only silicon dioxide, but also all compounds obtained by the layer, such as silicon hydroxide, silicon oxide hydroxide and water-containing silica phase.

[0032] Any suitable aluminum oxide precursor can be used to form the aluminum oxide layer. Preferably, sodium aluminate, aluminum sulfate, aluminum nitrate or aluminum chloride is used as the precursor and the layer can be formed by known methods and techniques such as adding a base to adjust the pH to the range of 4 to 9, preferably 7. The addition of the precursor is preferably carried out under stirring and at an elevated temperature if necessary. The precursor can be added to the suspension over a period of 5 to 60 minutes, preferably 30 minutes. The resulting aluminum oxide layer of the present invention includes not only aluminum oxide but all compounds obtained by the layer such as alumina hydroxide, aluminum oxide hydroxide and water-containing alumina phase.

[0033] Any suitable zirconia precursor can be used to form the zirconium dioxide layer. Preferably, zirconium oxychloride, zirconium sulfate and zirconium carboxylate are used as precursors and the layer can be formed by using methods and techniques known in the art. The addition of the precursor is preferably carried out under stirring and at an elevated temperature if necessary. The precursor can be added to the suspension over a period of 5 to 60 minutes, preferably 30 minutes. The resulting zirconium dioxide layer of the present invention contains not only zirconium dioxide but also all compounds obtained by the layer, such as zirconium hydroxide, zirconium oxide hydroxide and water-containing zirconium phases.

[0034] Any suitable manganese oxide precursor can be used to form the manganese dioxide layer. Preferably, anhydrous manganese sulfate, as well as manganese sulfate including monohydrate, tetrahydrate and heptahydrate, manganese nitrate including anhydrous and tetrahydrate and heptahydrate. Manganese carbonate treated with acid can also be used as a precursor and the layer can be formed by using methods and techniques known in the art. The addition of the precursor is preferably carried out under stirring and at an elevated temperature if necessary. The precursor can be added to the suspension over a period of 5 to 60 minutes, preferably 30 minutes. The resulting manganese dioxide layer of the present invention is composed of not only manganese dioxide but also MnOOH and Mn(II)Mn(III) 2 O 4 This includes all compounds obtained by layers such as

[0035] When forming a mixture of silicon dioxide, aluminum oxide and zirconium dioxide layers, the respective precursors can be used. Furthermore, the combination of silicon dioxide, aluminum oxide and zirconium dioxide layers can be formed by forming a single layer containing a mixture of the two layer materials, either a homogeneous mixture or varying gradients of each layer material, or by forming successive layers of the separate layer materials. The various methods of forming each type of layer, mixed layers and multilayer layers are well known to those skilled in the art.

[0036] The coloring component used in step c) of the process according to the invention is Co 3 (PO 4 ) 3 , N.H. 4 MnP 2 O 7 , Fe 4 [Fe(CN) 6 ] 3 , PbCrO 4 , BaMnO 4 , BaCrO 4 , Fe(OH) 3 , Fe(OH) 2 , Cu(OH) 2 , Ni(OH) 2 , Co(OH) 2 , Cr(OH)3 、Mn(OH) 2 、V(OH) 5 、Bi(OH) 3 、Ce(OH) 3 、FeO、Fe 2 A 3 ,With 2 O、CuO、CoO、CrO、Cr 2 A 3 、CrO 2 、MnO、Mn 2 A 3 、Mn 3 A 4 ,VO,V 2 A 3 、VO 2 、V 2 A 5 、Bi 2 A 3 、Bi 2 A 5 、At 2 A 3 、La(OH) 3 、CeO 2 ,What 2 A 3 ,What 3 A 4 、Ce(OH) 3 、Ce(OH) 4 、Pr 6 A 11 、Pr(OH) 3 ,Us 2 A 3 、Nd(OH) 3 ,P.m 2 A 3 、Pm(OH) 3 、Sm 2 A 3 、Sm(OH) 3 ,I 2 A 3 、I(OH) 3 、Gd 2 A 3 、Gd 2 (OH) 3 、Tb 4 A 7 、Tb(OH) 3 、Dy 2 A 3 、Dy(OH) 3 、Ho 2 A3 , Ho(OH) 3 , Er 2 O 3 , Er(OH) 3 , Tm 2 O 3 , Tm(OH) 3 , Yb 2 O 3 , Yb(OH) 3 , Lu 2 O 3 , and Lu(OH) 3 is selected from the group consisting of:

[0037] The coloring component can be oxidized during the addition to the suspension or immediately during step c) or in step d). As oxidizing agent air, oxygen, hydrogen peroxide or other known oxidizing agents can be used at a pH of at least 2, preferably at least 4.

[0038] Preferably, the coloring component is added in an amount such that the resulting color pigment particles contain 0.5% to 10% by weight, preferably 0.75% to 6% by weight, more preferably 1% to 2% by weight of the coloring component based on the total weight of the color pigment particles.

[0039] The present invention further relates to compositions comprising the color pigments claimed herein. In preferred embodiments, the compositions are coatings, lacquers, paints, plastics, papers, and inks.

[0040] As plastic, any plastic known in the art and suitable for the purpose according to the invention can be used. As used herein, "plastic" refers to a material containing at least 50% by weight of a polymer, based on the total weight of the plastic. The polymer may be a homopolymer, a copolymer or a grafted polymer. Furthermore, the polymer may be an atactic, isotactic or syndiotactic polymer. Furthermore, the plastic is a thermoplastic, an elastomer, a thermoset or a thermoplastic elastomer, preferably a thermoset. Without being limited thereto, the polymer is selected from the group consisting of polyolefins, polystyrenes, polyamides, polyketones, polyesters, polyurethanes, poly(meth)acrylates, and mixtures thereof. Without being limited thereto, the polyolefins are selected from the group consisting of polyethylenes, polypropylenes, polybutylenes, and mixtures thereof. The color pigment particles can be incorporated into the plastic by known techniques and methods, for example by extrusion. The color pigment particles are processed into the plastic in the usual amounts. The resulting plastics therefore contain from 0.1 to 30% by weight, preferably from 1 to 25% by weight, of the agent according to the invention, based on the total weight of the plastic.

[0041] Finally, the present invention relates to the use of the color pigment particles for coloring coatings, lacquers, paints, plastics, papers, laminates, building materials or inks, including but not limited to cement, mortar, stone, blocks, clinker and plastering materials. EXAMPLES

[0042] Preparation of colored pigment particles Example 1a: Fe as a coloring component 2 O 3 Preparation of color pigment particles having A titanium dioxide pigment suspension was obtained by mixing titanium dioxide pigment particles (200 g) with water (1 l). The suspension was heated to 60° C. and the pH value was reduced to 2 by adding acid.

[0043] Next, FeSO 4 and water to obtain Fe 2 O 3 Calculated as FeSO 4 An aqueous solution (20 ml, 5% by weight based on the weight of water) was prepared. This aqueous solution was added to the titanium dioxide-based pigment suspension over a period of 10 minutes. Then, FeSO 4 Fe 2 O 3 Enough H to convert 2 O 2 Slowly add Fe 2 O 3 A dispersion was obtained.

[0044] Sodium aluminate was then added over a period of 30 minutes in an amount to provide a 2.4% by weight aluminum oxide layer relative to the total weight of the color pigment particles. The pH was then adjusted to a value of about 7 to complete the layer formation. The color pigment particles were filtered, washed and dried.

[0045] Example 1b: Fe as a coloring component 2 O 3 Preparation of color pigment particles having According to the protocol of Example 1a, except that 40 ml of Fe 2 O 3 Aqueous solutions were used to obtain colored pigment particles.

[0046] Example 1c: Fe as a coloring component 2 O 3 Preparation of color pigment particles having According to the protocol of Example 1a, except that 80 ml of Fe 2 O 3 Aqueous solutions were used to obtain colored pigment particles.

[0047] Example 1d: Fe as a coloring component 2 O 3Preparation of color pigment particles having According to the protocol of Example 1d, except that 160 ml of Fe 2 O 3 Aqueous solutions were used to obtain colored pigment particles.

[0048] CIELAB Determination The lightness (L * ) and color tone (a * ) and (b * ) was measured as follows: A water-based lacquer formulation containing Acronal LR 9014, commercially available from BASF, Germany, as binder was prepared and stirred. Color pigment particles were then added and mixed until a homogeneous mixture was obtained. The mixture was then applied using a Film Applicator 510, available from Erichsen GmbH & Co. KG, Germany, onto a chart available from Leneta Company, USA, to obtain a film with a thickness of 200 μm. The film was dried for 24 hours in a dust-free environment. CIELAB results were determined using an apparatus Colour-view, Lichtart C / 2°, available from Byk Gardner, Germany.

[0049] The CIELAB results for Examples 1a to 1d are shown in FIG.

[0050] result The color point is Fe 2 O 3 It can be seen that each value (a * , b * , L * ) was adjusted based on the Fe used in each experiment. 2 O 3 is related to the amount of

[0051] Test Methods and Results Particle size measurement The size of the titanium dioxide particles was measured using a CPS disc centrifuge, Model DC 20000, available from CPS Instrument, Inc., Florida, USA. The samples were prepared by mixing 2 g of dry pigment particles with 80 g of sodium hexametaphosphate solution (0.06% by weight in water) to obtain a first premix. Sodium hexametaphosphate is commercially available under the name Calgon N from BK Giulini GmbH, Ledenburg, Germany, until the first premix was homogenized. 2 g of this first premix was then added to the sodium hexametaphosphate solution (0.06% by weight in water) and mixed again to obtain a second premix. 100 μl of this second premix was used as the sample for determining the particle size. The centrifuge was operated at 3,000 rpm. The calibration standard parameters were as follows:

[0052] Particle density: 1.385g / mL Peak diameter: 1.27μL Peak half-width: 0.08μL

[0053] The fluid parameters were as follows: Fluid density: 1.045g / mL Fluid refractive index: 1.344 Fluid viscosity: 1.2cps

Claims

1. A color pigment particle comprising a titanium dioxide-based pigment and at least one layer, said at least one layer being modified with a coloring component; Colored pigment particles.

2. The colored pigment particle of claim 1 , wherein the pigment particle comprises an additional layer.

3. a) said at least one layer is located between said titanium dioxide-based pigment and said further layer; and / or b) the further layer is located between the titanium dioxide-based pigment and the at least one layer; The colored pigment particles of claim 2 .

4. 3. The color pigment particle of claim 2, wherein said further layer is modified with a color pigment.

5. 3. The color pigment particle of claim 2, wherein the at least one layer and the further layer are independently selected from the group consisting of silicon dioxide, aluminum oxide, zirconium oxide, manganese oxide, cerium oxide, titanium dioxide, sulfate and phosphate based inorganic compounds or mixtures thereof.

6. The color pigment particle of claim 1 , wherein the color pigment particle comprises a final layer comprising a silicon-based organic compound.

7. The coloring component is Co ３ (PO ４ ) ３ , NH ４ MnP ２ O ７ , Fe ４ [Fe(CN) ６ ３ , PbCrO ４ , BaMnO ４ , BaCrO ４ , Fe(OH) ３ , Fe(OH) ２ , Cu(OH) ２ , Ni(OH) ２ , Co(OH) ２ , Cr(OH) ３ , Mn(OH) ２ , V(OH) ５ , Bi(OH) ３ , Ce(OH) ３ , FeO, Fe ２ O ３ , Cu ２ O, CuO, CoO, CrO, Cr ２ O ３ , CrO ２ , MnO, Mn ２ O ３ , Mn ３ O ４ , VO, V ２ O ３ , VO ２ , V ２ O ５ , Bi ２ O ３ , Bi ２ O ５ , La ２ O ３ , La(OH) ３ , CeO ２ , Ce ２ O ３ , Ce ３ O ４ , Ce(OH)[[ID=9۹]] ３ , Ce(OH) ４ , Pr ６ O １１ , Pr(OH) ３ [[ID=۱۰۸]], Ne ２ O ３ , Nd(OH) ３ , Pm ２ ​O ３ , Pm(OH) ３ , Sm ２ O ３ , Sm(OH) ３ , Eu ２ O ３ , Eu(OH) ３ , Gd ２ O ３ , Gd ２ (OH) ３ , Tb ４ O ７ , Tb(OH) ３ , Dy ２ O ３ , Dy(OH) ３ , Ho ２ O ３ , Ho(OH) ３ , Er ２ O ３ , Er(OH) ３ , Tm ２ O ３ , Tm(OH) ３ , Yb ２ O ３ , Yb(OH) ３ , Lu ２ O ３ , Lu(OH) ３ 2. The colored pigment particle of claim 1, selected from the group consisting of:

8. The coloring component is Co ３ (P.O. ４ ) ３ , N.H. ４ MnP ２ O ７ , Fe ４ [Fe(CN) ６ ] ３ , PbCrO ４ , BaMnO ４ and BaCrO ４ 6. The colored pigment particle of claim 5, selected from the group consisting of:

9. 3. The colored pigment particle of claim 2, wherein the at least one layer and the further layer are modified with the same coloring component, or the at least one layer and the further layer are modified with different coloring components.

10. 2. The colored pigment particle of claim 1, wherein the pigment particle comprises 0.5% to 10% by weight, preferably 0.75% to 6% by weight, more preferably 1% to 2% by weight of the coloring component, based on the total weight of the colored pigment particle.

11. a) providing an aqueous suspension of a titanium dioxide based pigment; b) adding a layer precursor to the suspension; c) adding a coloring component to the suspension; d) forming a layer on the titanium dioxide-based pigment from the layer precursor modified with the coloring component to obtain colored pigment particles; 1. A method for obtaining colored pigment particles, comprising:

12. The coloring component is Co ３ (PO ４ ) ３ , NH ４ MnP ２ O ７ , Fe ４ [Fe(CN) ６ ３ , PbCrO ４ , BaMnO ４ , BaCrO ４ , Fe(OH) ３ , Fe(OH) ２ , Cu(OH) ２ , Ni(OH) ２ , Co(OH) ２ , Cr(OH) ３ , Mn(OH) ２ , V(OH) ５ , Bi(OH) ３ , Ce(OH) ３ , FeO, Fe ２ O ３ , Cu ２ O, CuO, CoO, CrO, Cr ２ O ３ , CrO ２ , MnO, Mn ２ O ３ , Mn ３ O ４ , VO, V ２ O ３ , VO ２ , V ２ O ５ , Bi ２ O ３ , Bi ２ O ５ , La ２ O ３ , La(OH) ３ , CeO ２ , Ce ２ O ３ , Ce ３ O ４ , Ce(OH) ３ , Ce(OH) ４ , Pr ６ O １１ , Pr(OH) ３ , Ne ２ O ３ , Nd(OH) ３ , Pm ２ ​O ３ , Pm(OH) ３ , Sm ２ O ３ , Sm(OH) ３ , Eu ２ O ３ , Eu(OH) ３ , Gd ２ O ３ , Gd ２ (OH) ３ , Tb ４ O ７ , Tb(OH) ３ , Dy ２ O ３ , Dy(OH) ３ , Ho ２ O ３ , Ho(OH) ３ , Er ２ O ３ , Er(OH) ３ , Tm ２ O ３ , Tm(OH) ３ , Yb ２ O ３ , Yb(OH) ３ , Lu ２ O ３ , Lu(OH) ３ 12. The method of claim 11, wherein the coloring component is selected from the group consisting of:

13. 13. The method of claim 11 or 12, wherein the coloring component is added in an amount such that the resulting colored pigment particles contain 0.5% to 10% by weight, preferably 0.75% to 6% by weight, more preferably 1% to 2% by weight of said coloring component, based on the total weight of said colored pigment particles.

14. A composition comprising colored pigment particles according to any one of claims 1 to 10.

15. 11. Use of colored pigment particles according to any one of claims 1 to 10 for coloring coatings, lacquers, paints, plastics, paper, building materials or inks.

Images