Pigment composition containing plate-like aluminum with excellent explosion stability and method for preparing the same

Abstract

The present invention relates to a pigment composition containing plate-shaped aluminum having excellent explosion stability and a method for preparing the same. More specifically, the present invention relates to a pigment composition and a method for preparing the same, wherein the pigment composition contains thin aluminum flakes coated with a plurality of metal oxide layers and TiO2 coated with a metal oxide layer, thereby ensuring explosion stability. The pigment composition of the present invention can ensure stability against the thermite reaction caused by aluminum and metal oxides and prevent a decrease in chromaticity and hiding power by mixing TiO2 coated with a metal oxide layer having an apparent specific gravity lower than that of other plate-shaped inorganic particles.

Description

Technical Field

[0001] The present invention relates to a pigment composition containing plate-like aluminum having excellent explosion stability, a method for preparing the same, and uses thereof. More specifically, the present invention relates to a pigment composition, a method for preparing the same, and uses thereof, which ensure explosion stability by including thin aluminum flakes coated with multiple metal oxide layers and TiO2 coated with a metal oxide layer. This application claims priority to Korean Patent Application No. 10-2020-0167192, filed on December 3, 2020, and all the contents described in the specification and drawings of this application are incorporated into this application. Background Art

[0002] Pearlescent pigments are a general term for pearl-colored, rainbow-colored, and metallic pigments that utilize the properties of light and the refraction of substances to produce special color and luster effects, and are a type of special luster pigment. Ordinary pigments can only exhibit a specified color, but pearlescent pigments have the property of presenting different colors depending on the viewing angle, so they can be used in various industrial fields and are an area of continuous research and development. Due to the difference in the refractive index of the medium, rainbow colors or metallic lusters such as natural pearls can be produced, and a variety of metal oxides such as titanium dioxide, iron oxide, and silicon dioxide are mixed to achieve various colors and lusters.

[0003] However, if the metal substrate in the pigment contains aluminum, the thermic reaction may be a problem. The above-mentioned thermic reaction is an exothermic chemical reaction between aluminum and other metal oxides and needs to be suppressed.

[0004] Korean Patent No. 2107608 introduces a process for coating metal oxides by mixing non-metal fine particles in an aqueous coating step, but there is a problem of difficulty in uniformly coating colors due to differences in the specific gravity and specific surface area of non-metal fine particles and metal flakes.

[0005] Prior Art Documents

[0006] Patent Documents

[0007] Patent Document 1: Korean Patent No. 10-2107608 Summary of the Invention

[0008] Technical Problem

[0009] Therefore, the present inventors have studied and attempted to prepare a pigment composition that exhibits stability against explosions caused by the thermic reaction of aluminum and metal oxides. As a result, it has been found that a pigment composition having improved explosion stability while maintaining chromaticity and hiding power can be obtained by mixing thin aluminum flakes coated with multiple metal oxide layers and TiO2 coated with a metal oxide layer, thereby completing the present invention.

[0010] Technical solution

[0011] The present invention provides a pigment composition with improved explosion stability, which comprises: thin aluminum flakes coated with multiple metal oxide layers; and TiO2 coated with a metal oxide layer.

[0012] The average diameter of the above TiO2 can be 1 μm to 150 μm, and the thickness can be 10 nm to 500 nm.

[0013] The interior of the above TiO2 can include a hollow.

[0014] On the above thin aluminum flakes, a first oxide layer containing a metal oxide with a refractive index of 1.8 or less and a second oxide layer containing a metal oxide with a refractive index of 1.8 or more can be coated in sequence.

[0015] The above metal oxide can be one or a mixture of two or more selected from Fe2O3, SnO2, ZrO2, SiO2, MgO2, MgO2O3, K2O2, MnO, and Mg2SiO4.

[0016] The metal oxide layer coating the above TiO2 can contain Fe2O3.

[0017] The above thin aluminum flakes and TiO2 can be mixed in a weight ratio of 1:9 to 7:3.

[0018] The above pigment composition can be used in industrial coatings, varnishes, automotive coatings, powder coatings, printing inks, or cosmetics.

[0019] On the other hand, the present invention provides a method for preparing a pigment composition, which includes the following steps:

[0020] Coat the thin aluminum flakes with a first oxide layer and a second oxide layer in sequence to obtain coated thin aluminum flakes;

[0021] Coat TiO2 on the plate-like flakes;

[0022] Perform acid treatment and alkali treatment on the plate-like flakes coated with the above TiO2 to obtain TiO2 plate-like particles with the plate-like flakes removed;

[0023] Obtain coated TiO2 plate-like particles by coating a metal oxide on the surface of the above TiO2 plate-like particles; and

[0024] Mix the above coated thin aluminum flakes and the above coated TiO2 plate-like particles.

[0025] Coated TiO2 plate-like particles can be obtained by coating a metal oxide containing Fe2O3 on the surface of the above TiO2 plate-like particles.

[0026] The above-mentioned coated thin aluminum flakes and the above-mentioned coated TiO2 plate-like particles can be dry-mixed.

[0027] Advantages of the Invention

[0028] The pigment composition of the present invention can ensure the stability against the thermite reaction caused by aluminum and metal oxides and prevent the reduction of chromaticity and hiding power by mixing TiO2 coated with a metal oxide layer having an apparent specific gravity lower than that of other plate-like inorganic particles. Detailed Description of the Invention

[0029] Hereinafter, the present invention will be described in detail. Before that, the terms or words used in this specification and the claims of the invention are not limited to the conventional meanings or the meanings in the dictionary. Based on the principle that the inventor can appropriately define the concept of the term in order to best explain his invention, it should be interpreted as the meaning and concept conforming to the technical idea of the present invention. Therefore, the structure described in the embodiments in this specification only belongs to the most preferred embodiment of the present invention and does not fully represent the technical idea of the present invention. It should be understood that there may be various equivalent technical solutions and multiple modification examples that can be substituted at the time of this application.

[0030] The present invention is characterized in that the pigment composition of the present invention comprises: thin aluminum flakes coated with a plurality of metal oxide layers; and TiO2 coated with a metal oxide layer.

[0031] The above-mentioned TiO2 is in the shape of a plate and may include a hollow penetrating the inner center, but is not limited thereto. When the above-mentioned TiO2 includes a hollow core, since the weight becomes lighter and the apparent specific gravity is lower than that of other plate-like inorganic pigments, the same explosion stability can be ensured even at a mixing ratio lower than that of other pigments.

[0032] The average diameter of the above-mentioned TiO2 can be 1 μm to 150 μm, and the thickness can be 10 nm to 500 nm. If it includes a hollow penetrating the inner center, it represents the thickness of the substrate itself minus the hollow.

[0033] Moreover, depending on the thickness, the above-mentioned TiO2 can exhibit different interference colors. Specifically, if the thickness is 30 nm to 70 nm, it exhibits a white interference color; if the thickness is 70 nm to 100 nm, it exhibits a gold interference color; if the thickness is 100 nm to 120 nm, it exhibits a red interference color; if the thickness is 120 nm to 140 nm, it exhibits a violet interference color; if the thickness is 140 nm to 160 nm, it exhibits a blue interference color; if the thickness is 170 nm to 190 nm, it exhibits a green interference color.

[0034] A metal oxide layer is coated on the surface of the above TiO₂. The above metal oxide may include one or a mixture of two or more selected from Fe₂O₃, SnO₂, ZrO₂, SiO₂, MgO₂, MgO₂O₃, K₂O₂, MnO, and Mg₂SiO₄. Preferably, however, it may include Fe₂O₃.

[0035] With respect to 100 parts by weight of TiO₂, the content of the above metal oxide may be 10 to 100 parts by weight, preferably 20 to 80 parts by weight, more preferably 25 to 50 parts by weight, and most preferably 25 to 35 parts by weight.

[0036] Moreover, a plurality of metal oxide layers are coated on the surface of the above thin aluminum sheet. The average diameter of the above thin aluminum sheet may be 1 μm to 150 μm, and the thickness may be 10 nm to 500 nm.

[0037] A first oxide layer containing a metal oxide with a refractive index of 1.8 or less and a second oxide layer containing a metal oxide with a refractive index of 1.8 or more may be successively coated on the above thin aluminum sheet. Preferably, the metal oxide contained in the above first oxide layer may be SiO₂, and the metal oxide contained in the above second oxide layer may be Fe₂O₃, but it is not limited thereto.

[0038] In the pigment composition of the present invention, the above thin aluminum sheet coated with a plurality of metal oxide layers and the TiO₂ coated with a metal oxide layer can be mixed at a weight ratio of 1:9 to 7:3. Preferably, they can be mixed at a weight ratio of 3:7 to 6:4, and most preferably, they can be mixed at a weight ratio of 4:6 to 5:5.

[0039] The pigment composition of the present invention can be used in industrial coatings, varnishes, automotive coatings, powder coatings, printing inks, or cosmetics.

[0040] Moreover, the present invention is characterized in that it provides a method for preparing a pigment composition, including the following steps:

[0041] Coat the thin aluminum sheet with a first oxide layer and a second oxide layer in sequence to obtain a coated thin aluminum sheet;

[0042] Coat TiO₂ on a plate-shaped thin sheet;

[0043] Perform acid treatment and alkali treatment on the plate-shaped thin sheet coated with the above TiO₂ to obtain TiO₂ plate-shaped particles with the plate-shaped thin sheet removed;

[0044] Obtain coated TiO₂ plate-shaped particles by coating a metal oxide on the surface of the above TiO₂ plate-shaped particles; and

[0045] Mix the above coated thin aluminum sheet and the above coated TiO₂ plate-shaped particles.

[0046] First, a first oxide layer and a second oxide layer are sequentially coated on a thin aluminum sheet.

[0047] Preferably, the metal oxide contained in the first oxide layer may be SiO2, and the metal oxide contained in the second oxide layer may be Fe2O3.

[0048] Specifically, the above-mentioned thin aluminum sheet can be added to a solvent, a Si precursor compound is added and stirred, and then an alkaline solution is added and further stirred to form a first passivation layer containing SiO2.

[0049] As the above-mentioned Si precursor compound, tetraethyl orthosilicate (TEOS), tetramethyl orthosilicate (TMOS), etc. can be used.

[0050] Next, the thin aluminum sheet formed on the first passivation layer can be added to deionized water, an Fe precursor compound is added and stirred, and then heat treatment is performed to form a second passivation layer containing Fe2O3. In this case, preferably, a pH regulator is used to adjust the pH within the range of 1 to 5, and more preferably, the pH is adjusted within the range of 2 to 4.

[0051] As the above-mentioned Fe precursor compound, FeCl3, Fe(NO3)3, FeSO4, etc. can be used.

[0052] After dehydrating, washing with water, and drying the thin aluminum sheet formed with the second passivation layer, a coated thin aluminum sheet as the first component in the pigment composition can be obtained by performing heat treatment at 200°C to 400°C.

[0053] Next, a separate plate-like thin sheet is prepared, and TiO2 is coated on the surface of the above-mentioned thin sheet.

[0054] Specifically, the above-mentioned plate-like thin sheet is suspended in deionized water, and under acidic conditions with a pH of 1 to 5, preferably a pH of 1.5 to 2.5, a Ti precursor compound and an alkaline solution are added, and then stirred and calcined to form a TiO2 coating layer.

[0055] As the above-mentioned Ti precursor compound, TiCl4, TiOCl2, Ti(SO4)2, Ti(NO3)4, etc. can be used.

[0056] Preferably, the above-mentioned plate-like flakes may include one or more selected from mica, plate-like silica, and glass flakes, and mica among them is preferably used. Such plate-like flakes can be used in the form of pulverized and classified powders, or pulverized and classified after preparing the powders.

[0057] Preferably, the above-mentioned plate-like flakes with an average diameter of 1 μm to 150 μm are used. When the average diameter of the plate-like flakes is less than the above range, when the coating material is applied to the surface of the plate-like flake substrate, as the coating thickness increases, the plate-like flake substrate gradually becomes spherical, resulting in a decrease in the aspect ratio. If the aspect ratio decreases, it will cause diffuse reflection, resulting in light scattering, and there is a problem that the same color with the same specified refractive index cannot be presented. On the contrary, when the average diameter of the plate-like flakes is greater than the above range, it may be difficult to form a coating layer for realizing the color due to the increase in the coated surface area.

[0058] TiO2 is coated on the surface of the above-mentioned plate-like flakes, and the thickness of the TiO2 coating layer can be 10 nm to 1000 nm. Preferably, the thickness can be 50 nm to 500 nm, and more preferably, the thickness can be 100 nm to 300 nm.

[0059] Next, the plate-like flakes coated with the above-mentioned TiO2 are subjected to acid treatment and alkali treatment to obtain TiO2 plate-like particles with the plate-like flakes removed.

[0060] First, in a state where the plate-like flakes coated with TiO2 are mixed and suspended in deionized water, an acidic solution can be added for the first acid treatment, and then backflow washing and filtration are carried out.

[0061] In this case, more preferably, during the acid treatment, while stirring at a speed of 300 rpm to 500 rpm, ultrasonic waves are applied under the conditions of 15 kHz to 40 kHz and an output power of 70 W to 110 W.

[0062] When the stirring speed is less than 300 rpm or the ultrasonic output power is less than 70 W, the stirring may be insufficient. On the contrary, when the stirring speed is greater than 500 rpm or the ultrasonic output power is greater than 110 W, since the particles are severely broken and a lot of unnecessary small-sized particles are generated, it is difficult to control the size to the required size or perform post-treatment.

[0063] In this case, as the acidic solution, one selected from sulfuric acid, phosphoric acid, and nitric acid can be used alone, or a mixed solution formed by mixing two or more of them can be used. As such an acidic solution, an acidic solution diluted to a concentration of 40 wt% to 60 wt% is preferably used. When the concentration of the acidic solution is less than the above range, it may be difficult to ensure a hollow structure because the plate-like flakes cannot be well dissolved during the first acid treatment. On the contrary, when the concentration of the acidic solution is greater than the above range, due to the excessive concentration, there may be a problem that the coated TiO2 coating layer and the plate-like flakes are dissolved together.

[0064] In this step, preferably, at 80°C to 120°C, reflux for 4 to 6 hours. When the reflux temperature is less than 80°C or the reflux time is less than 4 hours, a sufficient dissolution rate may not be ensured, and surface cracks may be caused by insoluble plate-like flakes due to the generation of non-uniform hollow spheres. On the contrary, when the reflux temperature is greater than 120°C or the reflux time is greater than 6 hours, the hollow sphere coating layer may break or the TiO2 coating layer may separate due to stirring, so it is not preferred.

[0065] After the above acid treatment, a second alkali treatment can be carried out by adding an alkaline solution in a state where deionized water is mixed and suspended in the dehydrated and washed product, and then refluxing and filtering are carried out.

[0066] Preferably, the above alkaline solution uses a strong base with a concentration of 40 wt% to 55 wt%, specifically, one or more selected from sodium hydroxide and potassium hydroxide can be used.

[0067] When the concentration of the alkaline solution is less than 40 wt%, the TiO2-coated plate-like flakes of the first acid treatment are not completely dissolved, so a hollow morphology may not be formed. On the contrary, when the concentration of the alkaline solution is greater than 55 wt%, due to the excessive concentration, the plate-like flake substrate and the coated TiO2 layer may be dissolved together, so it is not preferred.

[0068] In this case, preferably, at 50°C to 70°C, reflux for 1 to 3 hours.

[0069] Through the above process, in a state where more than half of the plate-like flakes are removed by the first acid treatment of the plate-like flakes formed with the TiO2 coating layer, the second alkali treatment is carried out, so the plate-like flakes can be completely removed, thereby forming a hollow hollow structure.

[0070] By drying the product of the above alkali treatment, TiO2 plate-like particles with a hollow structure from which the plate-like flakes are removed can be obtained.

[0071] In this case, preferably, it is dried at 100°C to 150°C for 10 to 120 minutes. When the drying temperature is less than 100°C, the drying time may become longer, resulting in reduced economy and productivity. On the contrary, when the drying temperature is greater than 150°C, aggregation increase may occur between the powder particles, so it is not preferred.

[0072] Next, a metal oxide is coated on the surface of the above TiO2 plate-like particles to obtain coated TiO2 plate-like particles.

[0073] The above metal oxide may contain Fe2O3. Specifically, it can be added to deionized water, an Fe precursor compound is added and stirred, and then heat treatment is carried out to form a second passivation layer containing Fe2O3. In this case, preferably, a pH regulator is used to adjust the pH within the range of 1 to 5, and more preferably, the pH is adjusted within the range of 2 to 4.

[0074] As the above Fe precursor compound, FeCl3, Fe(NO3)3, FeSO4, etc. can be used.

[0075] After coating the metal oxide containing the above Fe2O3, dehydration, water washing and drying are carried out, and then heat treatment is carried out at 500°C to 1000°C to obtain coated TiO2 plate-like particles as the second component in the pigment composition.

[0076] Next, the final pigment composition is obtained by mixing the above coated thin aluminum flakes and the above coated TiO2 plate-like particles.

[0077] The above coated thin aluminum flakes and coated TiO2 plate-like particles can be mixed in a weight ratio of 1:9 to 7:3, preferably, in a weight ratio of 3:7 to 6:4, and most preferably, in a weight ratio of 4:6 to 5:5. And preferably, the above coated thin aluminum flakes and the above coated TiO2 plate-like particles are dry-mixed in a state separated from an aqueous solvent or the like.

[0078] Hereinafter, in order to specifically illustrate the present invention, examples and experimental examples are given for detailed description. However, the examples of the present invention can be deformed into various different forms, and the scope of the present invention should not be construed as limited to the examples described below. The examples of the present invention are provided to more completely illustrate the present invention to those of ordinary skill in the technical field to which the present invention pertains.

[0079] Preparation Example 1: Preparation of Coated Thin Aluminum Flakes

[0080] 100 g of thin aluminum sheets with a D50 of 15 μm were added to 490 g of isopropyl alcohol (IPA) to prepare the first slurry. Subsequently, 50 g of tetraethyl orthosilicate (TEOS) was added to the first slurry, and stirring was carried out at 400 rpm using a 7.5 cm impeller. Then, the above first slurry was heated to 50 °C, and 140 g of H2O and 5 g of 25% ammonia water were added. Subsequently, while maintaining 50 °C, stirring was carried out for about 20 hours to form a first passivation layer made of silicon oxide. Then, dehydration / washing was carried out with IPA, and then drying was performed.

[0081] 30 g of the thin aluminum sheets coated with the above first passivation layer were added to 300 g of pure water to prepare the second slurry, and stirring was carried out at 400 rpm using a 7.5 cm impeller. Subsequently, the temperature was raised to 75 °C, the pH was adjusted to 3.0, and then reflux was carried out for 30 minutes. Then, an aqueous FeCl3 solution was added while maintaining pH 3.0. In this case, caustic soda was used to maintain the pH. At the initial stage of adding the aqueous FeCl3 solution, it showed a copper color. As the amount of the aqueous FeCl3 solution added increased, it was confirmed that the color changed from copper to gold, and then the addition of the aqueous FeCl3 solution was stopped. Then, the powder obtained by dehydration, washing, and drying with pure water was heat-treated at 300 °C for 1 hour to obtain coated thin aluminum sheets.

[0082] Preparation Example 2: Preparation of Hollow Coated TiO2 Plate-Like Particles

[0083] First, 100 g of mica particles were suspended in 2 L of deionized water, and then, while maintaining a pH of 1.5 at 80 °C, a 40 wt% TiOCl2 solution and a sodium hydroxide solution were added simultaneously. Thereby, a TiO(OH)2 coating layer was formed on the surface of the mica particles. When the desired interference color was obtained, after stopping the addition of TiOCl2 and the sodium hydroxide solution, stirring was carried out for more than 10 minutes, followed by washing and drying, and then calcination was carried out at 850 °C to form a TiO2 coating layer on the surface of the synthetic mica particles.

[0084] Next, acid treatment and alkali treatment were carried out to prepare plate-like TiO2 particles. First, a condenser was installed in the reactor, and then 400 ml of sulfuric acid was added while stirring at 400 rpm. Then, reflux was carried out at 100 °C for 6 hours. After cooling, 800 ml of water was added and reflux was carried out again. After that, it was filtered using filter paper and washed 4 times with 1000 ml of water. Next, the powder after acid treatment was added to a 3 L flask, 800 ml of deionized water was added, and it was stirred at a speed of 400 rpm to make it suspended. Then, 400 ml of an aqueous sodium hydroxide solution with a concentration of 50 wt% was added, and reflux was carried out at 60 °C for 4 hours. After that, it was filtered using filter paper, then washed 4 times with 800 ml of water, and then dried at 120 °C to prepare hollow TiO2 plate-like particles.

[0085] 30 g of the above-mentioned hollow TiO2 plate-like particles was added to 500 g of pure water to form a slurry, and it was stirred at 400 rpm using a 7.5 cm impeller. After that, the temperature was raised to 75 °C, the pH was adjusted to 3.0, and then reflux was carried out for 30 minutes. Next, an aqueous FeCl3 solution was added while maintaining the pH at 3.0. In this case, caustic soda was used to maintain the pH. As the amount of the aqueous FeCl3 solution added increased, the color changed to golden, and then the addition of the aqueous FeCl3 solution was stopped. After that, the powder obtained by dehydration, washing with water, and drying with pure water was heat-treated at 800 °C for 1 hour to obtain hollow coated TiO2 plate-like particles.

[0086] Example 1: Preparation of a pigment composition

[0087] A pigment composition was prepared by mixing the coated thin aluminum sheets prepared in Preparation Example 1 above and the coated TiO2 plate-like particles prepared in Preparation Example 2 above.

[0088] Experimental Example 1: Confirmation of explosive stability

[0089] In the pigment composition of Example 1 above, the coated thin aluminum sheets and the coated TiO2 hollow plate-like particles were mixed at different dry mixing ratios, and the corresponding explosive forces were measured. The results are shown in Table 1 below.

[0090] The following explosive forces are the comparison of the explosion degrees after the thermit reaction was caused by directly contacting the flame with 3 g of the powder. In this case, the explosion degree represents the relative comparison value based on the explosive force of the coated thin aluminum sheets alone (100%) being 10.

[0091] Table 1

[0092]

[0093] As shown in Table 1 above, it can be confirmed that before the weight ratio of the coated thin aluminum sheet to the coated TiO2 plate-like particles reaches 5:5, the explosive force remains low, but the higher the weight ratio of the coated TiO2 plate-like particles, the greater the explosive force.

[0094] On the other hand, by mixing the above-mentioned coated thin aluminum sheet with ordinary TiO2 particles coated with synthetic mica (Mica) or metal oxide and confirming the explosive force in the same manner as above, the results are shown in Tables 2 to 4 below.

[0095] The synthetic mica used for comparison was plate-like synthetic mica with a D50 standard of about 20 um and a thickness of about 500 nm.

[0096] In addition, synthetic mica coated with TiO2 prepared in the following manner was used: the above synthetic mica was diluted to 10 wt% in pure water, and the pH was constantly maintained at 1.8 with TiOCl2 and sodium hydroxide at 70 °C until it turned gold, and then dehydration / washing and heat treatment were carried out.

[0097] In addition, synthetic mica coated with Fe2O3 prepared in the following manner was used: the above synthetic mica was diluted to 10 wt% in pure water, and then the pH was constantly maintained at 3.0 with FeCl3 and sodium hydroxide at 70 °C until it turned bronze, and then dehydration / washing and heat treatment were carried out.

[0098] Table 2

[0099]

[0100] Table 3

[0101]

[0102] Table 4

[0103]

[0104] As shown in Tables 2 to 4 above, it was confirmed that a high explosive force was maintained when the thin aluminum sheet and ordinary inorganic particles were mixed, so it can be confirmed that the pigment composition of the present invention ensures relative explosive stability.

[0105] Experimental Example 2: Confirming the chromaticity and hiding power of the pigment composition

[0106] Through the above experiment, it was confirmed that when the coated thin aluminum sheet and the coated TiO2 plate-like particles were mixed at a weight ratio of 5:5, the pigment composition of the present invention ensured explosive stability, and the chromaticity and hiding power of the pigment composition in which the coated thin aluminum sheet and other inorganic particles were mixed at a weight ratio of 5:5 were measured and compared, and the results are shown in Table 5 below.

[0107] In Table 5 above, the example represents a composition in which the coated thin aluminum sheet of Preparation Example 1 and the coated TiO2 plate-like particles of Preparation Example 2 are mixed at a weight ratio of 5:5.

[0108] On the other hand, in Table 5 below, Comparative Example 1 represents a composition in which the coated thin aluminum sheet of Preparation Example 1 and synthetic mica particles are mixed at a weight ratio of 5:5, Comparative Example 2 represents a composition in which the coated thin aluminum sheet of Preparation Example 1 and synthetic mica particles coated with TiO2 are mixed at a weight ratio of 5:5, and Comparative Example 3 represents a composition in which the coated thin aluminum sheet of Preparation Example 1 and synthetic mica particles coated with Fe2O3 are mixed at a weight ratio of 5:5.

[0109] Table 5

[0110]

[0111] In Table 5 above, C* represents chromaticity, and dC* represents the chromaticity difference from the coated thin aluminum sheet of Preparation Example 1.

[0112] As shown in Table 5 above, it can be confirmed that the pigment composition of the example exhibits excellent chromaticity and hiding power compared to other pigment compositions.

Claims

1. A pigment composition with improved explosion stability, characterized in that, Comprising: A thin aluminum sheet coated with multiple metal oxide layers; and TiO2 coated with a metal oxide layer, wherein the interior of the TiO2 includes a hollow, and the average diameter of the TiO2 is 1 μm to 150 μm, and the thickness is 10 nm to 500 nm, the metal oxide layer coating the TiO2 contains Fe2O3, the thin aluminum sheet and the TiO2 coated with the metal oxide layer are mixed at a weight ratio of 3:7 to 6:

4.

2. The pigment composition according to claim 1, characterized in that, The thin aluminum sheet is sequentially coated with a first oxide layer containing a metal oxide with a refractive index of 1.8 or less and a second oxide layer containing a metal oxide with a refractive index of 1.8 or more.

3. The pigment composition according to claim 1, characterized in that, The metal oxide of the metal oxide layer is one or a mixture of two or more selected from Fe2O3, SnO2, ZrO2, SiO2, MgO2, MgO2O3, K2O2, MnO, and Mg2SiO4.

4. The pigment composition according to claim 1, characterized in that, For industrial coatings, varnishes, automotive coatings, powder coatings, printing inks, or cosmetics.

5. A method for preparing a pigment composition, characterized in that, Including the following steps: Coating the thin aluminum sheet with the first oxide layer and the second oxide layer in sequence to obtain a coated thin aluminum sheet; Coating TiO2 on a plate-shaped thin sheet; Performing acid treatment and alkali treatment on the plate-shaped thin sheet coated with the TiO2 to obtain TiO2 plate-shaped particles with the plate-shaped thin sheet removed; Obtaining coated TiO2 plate-shaped particles by coating a metal oxide on the surface of the TiO2 plate-shaped particles; And Mixing the coated thin aluminum sheet and the coated TiO2 plate-shaped particles, wherein the interior of the TiO2 plate-shaped particles includes a hollow, and the average diameter of the TiO2 plate-shaped particles is 1 μm to 150 μm, and the thickness is 10 nm to 500 nm, the thin aluminum sheet and the coated TiO2 plate-shaped particles are mixed at a weight ratio of 3:7 to 6:

4.

6. The method for preparing the pigment composition according to claim 5, wherein Obtaining coated TiO2 plate-shaped particles by coating a metal oxide containing Fe2O3 on the surface of the TiO2 plate-shaped particles.

7. The method for preparing the pigment composition according to claim 5, wherein Dry-mixing the coated thin aluminum sheet and the coated TiO2 plate-shaped particles.

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