Titanium dioxide color master batch as well as preparation method and application thereof

Abstract

The invention relates to a titanium dioxide color master batch as well as a preparation method and application thereof. The titanium dioxide color master batch comprises the following components in parts by weight: 70-97 parts of titanium dioxide, 1-29 parts of calcium carbonate and 0.5-2 parts of polyvinylpyrrolidone. The D50 particle size of the calcium carbonate is 30 to 1260 nm; the mass ratio of the titanium dioxide to the calcium carbonate is (2.5-30): 1. The titanium dioxide color master batch provided by the invention is dust-free particles, is good in environmental protection property, regular in particle shape and moderate in fineness, has excellent flowability and bulk density, is convenient for precise metering, pneumatic conveying and automatic feeding, and has excellent automatic suitability; and meanwhile, uniform and stable white slurry can be formed after being dissolved in water, agglomerated particles and flocculates are avoided, and the dispersity is excellent.

Description

Technical Field

[0001] This invention belongs to the field of water-based coatings technology, specifically relating to a titanium dioxide masterbatch, its preparation method, and its application. Background Technology

[0002] With increasingly stringent environmental regulations, the use of solvent-based coatings is restricted, while water-based coatings continue to see market share growth due to their environmentally friendly characteristics. Titanium dioxide, as the most critical white pigment in water-based coatings, faces numerous challenges in actual production: the powder easily generates dust pollution, posing health and safety hazards; pigment particles tend to agglomerate, making uniform dispersion in water-based systems difficult, affecting the coating's hiding power, gloss, and stability; furthermore, the poor flowability of powdered materials leads to unstable feeding and inaccurate metering in automated production lines, severely restricting production efficiency and intelligent upgrades. Currently, research on masterbatches specifically for coatings is limited, and existing technologies have significant limitations.

[0003] CN112852099A discloses a color masterbatch for solvent-based coatings and its preparation method. The color masterbatch is made from the following raw materials in parts by weight: 50-70 parts carrier resin, 15-28 parts pigment, 6-12 parts dispersant, and 1-5 parts plasticizer. It uses modified aldehyde-ketone resin as a carrier to prepare color masterbatch for solvent-based coatings, but it cannot be used in water-based coatings. CN114835925A discloses a pre-dispersed aldehyde-ketone resin colored sand and its preparation method. The colored sand comprises the following components and their weight parts: 20-45 parts of color powder, 25-45 parts of aldehyde-ketone resin, 5-25 parts of polymer compatibilizer, 1-3 parts of oxidized polyethylene wax, 1-3 parts of ethylene bis-stearamide, 1-4 parts of calcium-zinc stabilizer, 1-4 parts of palm oil, 1-3 parts of calcium carbonate, 1-3 parts of mica, and 1-5 parts of additives. It uses aldehyde-ketone resin as a carrier and polymer compatibilizer to prepare colored sand for paint, but it cannot be used in water-based coatings. CN117402526A discloses an artistic coating with roll-applied overlay color effects and its preparation method. The artistic coating comprises the following raw materials by weight: 10-20 parts water, 30-60 parts premixed solution, 30-50 parts organic film-forming substance, and 3-5 parts additives. The premixed solution includes silica sol and color masterbatch in a mass ratio of 1:1-1.5. It uses plastic color masterbatch as color dots in building interior wall coatings. By introducing silica sol to modify the color masterbatch, its water solubility is improved to achieve artistic effects. However, it is only one type of color dot effect in water-based coatings, and the color masterbatch cannot be dispersed in water.

[0004] Therefore, there is an urgent need to provide a water-based titanium dioxide masterbatch that can be completely dispersed in water, has excellent dispersion performance, and is suitable for automated production. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a titanium dioxide masterbatch, its preparation method, and its application. Through component design, it exhibits excellent dispersibility in water, forming a uniform and stable white slurry free of agglomerated particles and flocculants. Furthermore, the particles have regular morphology, moderate fineness, excellent flowability and bulk density, facilitating precise metering, pneumatic conveying, and automatic feeding, and possessing excellent automation adaptability. Simultaneously, it consists of dust-free particles, completely solving the dust problem and demonstrating good environmental friendliness.

[0006] To achieve this objective, the present invention adopts the following technical solution: In a first aspect, the present invention provides a titanium dioxide masterbatch, wherein the titanium dioxide masterbatch comprises the following components by weight: 70-97 parts by weight of titanium dioxide Calcium carbonate 1-29 parts by weight 0.5-2 parts by weight of polyvinylpyrrolidone.

[0007] The D of the calcium carbonate 50 The particle size is 30-1260 nm, for example, it can be 50 nm, 100 nm, 200 nm, 300 nm, 400 nm, 500 nm, 600 nm, 700 nm, 800 nm, 900 nm, 1000 nm, 1100 nm, 1200 nm, etc.

[0008] In this invention, the D of the calcium carbonate 50 The particle size was obtained by laser particle size analyzer (Dandong Better Instruments Co., Ltd., BT-9300ST).

[0009] The mass ratio of titanium dioxide to calcium carbonate is (2.5-30):1, for example, it can be 3:1, 5:1, 8:1, 10:1, 12:1, 15:1, 18:1, 20:1, 22:1, 25:1, 28:1, etc.

[0010] In the titanium dioxide masterbatch provided by this invention, polyvinylpyrrolidone (PVP) can act as a dispersant and binder, and its dosage is low, so it will not affect the performance of the original pigments and fillers. Calcium carbonate, as a filler and dispersant, can be embedded between titanium dioxide particles, reducing the chance of direct contact and agglomeration of titanium dioxide particles, providing better spatial barrier, and effectively preventing titanium dioxide agglomeration. This is achieved by controlling the D of calcium carbonate. 50 When the particle size and the mass ratio of titanium dioxide to calcium carbonate are within a suitable range, the dispersibility of titanium dioxide masterbatch in water and the sphericity of titanium dioxide masterbatch can be improved.

[0011] The titanium dioxide is in the form of 70-97 parts by weight, for example, 72 parts by weight, 74 parts by weight, 76 parts by weight, 78 parts by weight, 80 parts by weight, 82 parts by weight, 84 parts by weight, 86 parts by weight, 88 parts by weight, 90 parts by weight, 92 parts by weight, 94 parts by weight, 96 parts by weight, etc.

[0012] The calcium carbonate is 1-29 parts by weight, for example, 2 parts by weight, 4 parts by weight, 6 parts by weight, 8 parts by weight, 10 parts by weight, 12 parts by weight, 14 parts by weight, 16 parts by weight, 18 parts by weight, 20 parts by weight, 22 parts by weight, 24 parts by weight, 26 parts by weight, 28 parts by weight, etc.

[0013] The polyvinylpyrrolidone is 0.5-2 parts by weight, for example, it can be 0.6 parts by weight, 0.7 parts by weight, 0.8 parts by weight, 0.9 parts by weight, 1 part by weight, 1.1 parts by weight, 1.2 parts by weight, 1.3 parts by weight, 1.4 parts by weight, 1.5 parts by weight, 1.6 parts by weight, 1.7 parts by weight, 1.8 parts by weight, 1.9 parts by weight, etc.

[0014] All "parts by weight" in this invention are calculated based on solid content and do not include solvents, dispersants, etc.

[0015] The following are preferred technical solutions of the present invention, but are not intended to limit the technical solutions provided by the present invention. The purpose and beneficial effects of the present invention can be better achieved and realized through the following preferred technical solutions.

[0016] As a preferred technical solution, the titanium dioxide masterbatch comprises the following components by weight: 77-94 parts by weight of titanium dioxide Calcium carbonate 4-20 parts by weight Polyvinylpyrrolidone 0.6-1.6 parts by weight.

[0017] Preferably, the titanium dioxide includes rutile titanium dioxide and / or anatase titanium dioxide.

[0018] Preferably, the calcium carbonate comprises light calcium carbonate and / or heavy calcium carbonate.

[0019] Preferably, the light calcium carbonate includes nano-calcium carbonate.

[0020] Preferably, the calcium carbonate has a D 50 The particle size is 200-400nm.

[0021] Small-sized calcium carbonate particles can fill the spaces between titanium dioxide particles more thoroughly, providing better barrier properties and effectively inhibiting the agglomeration of titanium dioxide. However, the particle size of calcium carbonate cannot be too small. Calcium carbonate with too small a particle size has high density and low porosity, which will hinder water penetration and thus degrade the dispersibility of titanium dioxide masterbatch. On the other hand, if the particle size of calcium carbonate is too large, it will affect the sphericity of titanium dioxide masterbatch.

[0022] Preferably, the mass ratio of titanium dioxide to calcium carbonate is (3.9-18.6):1.

[0023] Preferably, the K value of the polyvinylpyrrolidone is 27-33, for example, it can be 29, 30, 31, 32, etc.

[0024] Preferably, the titanium dioxide masterbatch further includes a wetting and dispersing agent.

[0025] Preferably, the wetting and dispersing agent is 0.5-2 parts by weight, for example, it can be 0.6 parts by weight, 0.7 parts by weight, 0.8 parts by weight, 0.9 parts by weight, 1 part by weight, 1.1 parts by weight, 1.2 parts by weight, 1.3 parts by weight, 1.4 parts by weight, 1.5 parts by weight, 1.6 parts by weight, 1.7 parts by weight, 1.8 parts by weight, 1.9 parts by weight, etc.

[0026] Preferably, the wetting and dispersing agent comprises a modified styrene-maleic anhydride copolymer and / or an anionic polymeric wetting and dispersing agent.

[0027] The wetting and dispersing agents include, but are not limited to, BYK's DISPERBYK-2015 or Evonik's TEGO. ® Dispers 755 W.

[0028] Preferably, the particle size of the titanium dioxide masterbatch is 1.25-2.5 mm, for example, it can be 1.4 mm, 1.6 mm, 1.8 mm, 2 mm, 2.2 mm, 2.4 mm, etc.

[0029] In this invention, the particle size test method for the titanium dioxide masterbatch is the standard test sieve sieving method. Standard test sieves with apertures of 2.5 mm and 1.25 mm are used for sieving to obtain particles with particle sizes between the two. A small number of particles that are too large or too small are excluded.

[0030] In a second aspect, the present invention provides a method for preparing titanium dioxide masterbatch as described in the first aspect, the method comprising the following steps: (1) Mix titanium dioxide and calcium carbonate to obtain a premixed dry powder; Polyvinylpyrrolidone, optionally a wetting and dispersing agent, and water are mixed to obtain an adhesive liquid; (2) The adhesive liquid is mixed with the premixed dry powder and granulated to obtain the titanium dioxide masterbatch.

[0031] Preferably, the adhesive liquid contains 5-15% polyvinylpyrrolidone by mass, for example, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, etc.

[0032] Preferably, the mixing method in step (2) includes atomizing the adhesive liquid and spraying it onto the premixed dry powder.

[0033] Preferably, the spraying rate is 2-4 mL / min, for example, it can be 2.2 mL / min, 2.4 mL / min, 2.6 mL / min, 2.8 mL / min, 3 mL / min, 3.2 mL / min, 3.4 mL / min, 3.6 mL / min, 3.8 mL / min, etc.

[0034] Preferably, the granulation method includes centrifugal shot blasting granulation.

[0035] Preferably, the centrifugal shot blasting granulation is carried out at a rotation speed of 150-200 rpm (e.g., 155 rpm, 160 rpm, 165 rpm, 170 rpm, 175 rpm, 180 rpm, 185 rpm, 190 rpm, 195 rpm, etc.).

[0036] Preferably, the centrifugal shot blasting granulation time is 20-30 min, for example, it can be 21 min, 22 min, 23 min, 24 min, 25 min, 26 min, 27 min, 28 min, 29 min, etc.

[0037] Preferably, the granulation process further includes a drying step.

[0038] Preferably, the drying temperature is 50-70℃, for example, it can be 52℃, 54℃, 56℃, 58℃, 60℃, 62℃, 64℃, 66℃, 68℃, etc.

[0039] Preferably, the drying process further includes a sieving step.

[0040] Thirdly, the present invention provides a water-based coating, wherein the raw materials for preparing the water-based coating include titanium dioxide masterbatch as described in the first aspect.

[0041] The numerical range described in this invention includes not only the point values ​​listed above, but also any point values ​​within the numerical ranges not listed above. Due to space limitations and for the sake of brevity, this invention will not exhaustively list all the specific point values ​​included in the range.

[0042] Compared with the prior art, the present invention has the following beneficial effects: (1) The titanium dioxide masterbatch provided by the present invention is a dust-free particle, which completely solves the dust problem and has good environmental performance; (2) The titanium dioxide masterbatch provided by the present invention has a regular particle shape, excellent flowability and bulk density, and moderate fineness, which facilitates precise metering, pneumatic conveying and automatic feeding, avoiding the problems of unstable feeding and easy accumulation of powder, and has excellent automation adaptability. (3) The titanium dioxide masterbatch provided by the present invention inhibits the agglomeration of titanium dioxide through PVP and calcium carbonate. PVP disperses rapidly when it comes into contact with water, releasing pigment particles. Combined with the auxiliary disintegration effect of calcium carbonate, it can achieve rapid and uniform dispersion of pigments in water-based coating systems, thereby improving the dispersibility of titanium dioxide masterbatch. (4) The titanium dioxide masterbatch provided by the present invention can form a uniform and stable white slurry in water, without agglomerated particles and flocculents. When the slurry is used to formulate water-based latex paint, the whiteness, hiding power and gloss of the paint film are all at the same level as those of the same amount of titanium dioxide used directly, and the production process is simpler. Detailed Implementation

[0043] To facilitate understanding of the present invention, the following embodiments are provided. Those skilled in the art should understand that these embodiments are merely illustrative and should not be construed as limiting the scope of the invention.

[0044] The sources of some components in the following examples and comparative examples are as follows: (1) Titanium dioxide: Titanium Dioxide-1, Jiangxi Tianguang Titanium Industry Co., Ltd., TIKON 33, rutile titanium dioxide, TiO2 content is 94%; Titanium Dioxide-2, Shanghai Yantai Industrial Co., Ltd., HA100, anatase titanium dioxide, TiO2 content ≥98%; (2) Nano calcium carbonate: Nano Calcium Carbonate-1, Guangdong Shichuan Shimei New Materials Co., Ltd., CAN-6600, CaCO3≥98% (dry basis), D 50 The particle size is 300 nm; Nano-calcium carbonate-2, Guangdong Jufu New Materials Co., Ltd., JFG-7111, CaCO3 content ≥98%, D 50 The particle size is 300 nm; Nano Calcium Carbonate-3, Xiamen Haichuanda Industry & Trade Co., Ltd., NCC-102, D 50 The particle size is 40 nm; Nano-calcium carbonate-4, Guangdong Shichuan Shimei New Materials Co., Ltd., CAH-6350, D 50The particle size is 1260 nm; (3) Polyvinylpyrrolidone (PVP) PVP-1, Lianyungang Ronghe New Material Technology Co., Ltd., PVP K30 (powder), K value 27-33, solid content >95%; PVP-2, Guangdong Yuemei Chemical Co., Ltd., PVP K30 (powder), K value 27-32; (4) Wetting and dispersing agent: BYK Additives (Shanghai) Co., Ltd., DISPERBYK-2015.

[0045] Example 1 A titanium dioxide masterbatch, wherein the titanium dioxide masterbatch comprises the following components by weight: Titanium dioxide - 180 parts by weight Nano calcium carbonate - 118 parts by weight PVP-11 parts by weight 1 part by weight of wetting and dispersing agent; The preparation method of the titanium dioxide masterbatch includes the following steps: (1) Mix titanium dioxide-1 and nano calcium carbonate-1 evenly to obtain a uniform premixed dry powder; PVP-1 was dissolved in deionized water and a wetting and dispersing agent was added to prepare an adhesive solution with a PVP-1 content of 5% by mass. (2) The premixed dry powder is added to a centrifugal shot blasting machine. After starting the equipment, the adhesive liquid is atomized and sprayed onto the premixed dry powder by pressure spraying for granulation. The speed of the centrifugal shot blasting machine is 165 rpm and the spraying rate is 3 mL / min. After centrifugal shot blasting and granulation for 25 min, the formed wet masterbatch is transferred to a fluidized bed dryer and dried under hot air conditions at 60°C. Finally, it is sieved through standard inspection sieves with apertures of 1.25 mm and 2.5 mm to obtain the titanium dioxide powder masterbatch.

[0046] Examples 2-10, Comparative Examples 1-4 A titanium dioxide masterbatch differs from Example 1 only in the type and / or amount (parts by weight) of the components, as shown in Tables 1 and 2; the preparation method of the titanium dioxide masterbatch is the same as that of Example 1.

[0047] Table 1 Table 2 Performance testing (1) Sphericality: After centrifugal shot blasting granulation, if the powder can agglomerate into spherical particles with smooth surface and regular shape, it is rated as excellent; if it is still loose powder and cannot agglomerate into spherical particles, it is rated as poor; if it can agglomerate into spheres but the surface is rough, it is rated as good. (2) Particle size distribution uniformity: The standard test sieve sieving method is used for evaluation. The specific operation is as follows: the dried masterbatch in the example and comparative example step (2) is sieved with standard test sieves with apertures of 1.25 mm and 2.5 mm to obtain qualified masterbatch with particle size between the two. The mass of qualified masterbatch is recorded as m1, and the mass of total masterbatch is recorded as m0. If m1 / m0×100%≥90%, it is qualified; otherwise, it is unqualified. (3) Dispersibility: Take 1g of titanium dioxide masterbatch, add it to 99g of deionized water, stir thoroughly until there is no residue or flocculent material at the bottom, and form a uniform and stable white slurry. Record the stirring time. (4) Fineness: The titanium dioxide masterbatch was tested using a scraper fineness tester according to GB / T6753.1-2007 standard.

[0048] Table 3 Note: In Table 3, " / " indicates that the relevant data was not tested.

[0049] As can be seen from the test data in Table 3, the titanium dioxide masterbatch provided by the present invention has regular particle shape, good sphericity, good uniformity of particle size distribution (90.2-93.1%), good dispersibility in water (118-174s), and moderate fineness (11-18μm).

[0050] As can be seen from Examples 1 and 4-6, the D of nano-calcium carbonate 50 When the particle size is within the preferred range, the sphericity or dispersibility of the titanium dioxide masterbatch can be further improved.

[0051] As can be seen from Examples 1 and 7-9, when the mass ratio of titanium dioxide to calcium carbonate is within the preferred range, the sphericity and dispersibility of titanium dioxide masterbatch can be maintained at a good level.

[0052] As shown in Comparative Example 1, the dispersibility of titanium dioxide masterbatch deteriorates without the use of calcium carbonate. This is because calcium carbonate particles can be dispersed between titanium dioxide particles, acting as a physical barrier and reducing the chance of direct contact and agglomeration of titanium dioxide particles, thereby improving the dispersibility of titanium dioxide masterbatch.

[0053] As can be seen from Comparative Example 2, the more calcium carbonate is used, the worse the sphericity of the powder becomes. This is because titanium dioxide has a regular morphology, is close to spherical, and is easy to pack tightly. However, calcium carbonate particles have an irregular morphology, which will cause voids or protrusions in the mixed system. If too much calcium carbonate is used, it is difficult to form spherical particles with smooth surfaces and regular morphology.

[0054] As shown in Comparative Example 3, when the PVP content is too low, the premixed powder after centrifugal shot blasting granulation is still a loose powder and cannot be agglomerated into spherical particles. This is because PVP, as a water-soluble binder and dispersant, cannot fully exert its adhesive effect when its dosage is too low.

[0055] As shown in Comparative Example 4, when the PVP content is too high, the powder is easily agglomerated into large particles, and the viscosity between the particles is high, making them prone to sticking together.

[0056] The applicant declares that this invention illustrates the titanium dioxide masterbatch, its preparation method, and its application through the above embodiments. However, this invention is not limited to the above embodiments, meaning that this invention does not necessarily rely on the above embodiments for implementation. Those skilled in the art should understand that any improvements to this invention, equivalent substitutions of raw materials for the product, addition of auxiliary components, and selection of specific methods, etc., all fall within the protection and disclosure scope of this invention.

Claims

1. A titanium dioxide masterbatch, characterized in that, The titanium dioxide masterbatch comprises the following components by weight: 70-97 parts by weight of titanium dioxide Calcium carbonate 1-29 parts by weight Polyvinylpyrrolidone 0.5-2 parts by weight; The D of the calcium carbonate 50 The particle size is 30-1260nm; the mass ratio of titanium dioxide to calcium carbonate is (2.5-30):

1.

2. The titanium dioxide masterbatch according to claim 1, characterized in that, The titanium dioxide masterbatch comprises the following components by weight: 77-94 parts by weight of titanium dioxide Calcium carbonate 4-20 parts by weight Polyvinylpyrrolidone 0.6-1.6 parts by weight.

3. The titanium dioxide masterbatch according to claim 1 or 2, characterized in that, The titanium dioxide includes rutile titanium dioxide and / or anatase titanium dioxide.

4. The titanium dioxide masterbatch according to claim 1 or 2, characterized in that, The calcium carbonate includes light calcium carbonate and / or heavy calcium carbonate; Preferably, the light calcium carbonate includes nano-calcium carbonate; Preferably, the calcium carbonate has a D 50 Particle size is 200-400 nm; Preferably, the mass ratio of titanium dioxide to calcium carbonate is (3.9-18.6):

1.

5. The titanium dioxide masterbatch according to claim 1 or 2, characterized in that, The K value of the polyvinylpyrrolidone is 27-33; Preferably, the titanium dioxide masterbatch further includes a wetting and dispersing agent; Preferably, the wetting and dispersing agent is 0.5-2 parts by weight; Preferably, the wetting and dispersing agent comprises a modified styrene-maleic anhydride copolymer and / or an anionic polymeric wetting and dispersing agent.

6. The titanium dioxide masterbatch according to claim 1 or 2, characterized in that, The particle size of the titanium dioxide masterbatch is 1.25-2.5 mm.

7. A method for preparing titanium dioxide masterbatch as described in any one of claims 1-6, characterized in that, The preparation method includes the following steps: (1) Mix titanium dioxide and calcium carbonate to obtain a premixed dry powder; Polyvinylpyrrolidone, optionally a wetting and dispersing agent, and water are mixed to obtain an adhesive liquid; (2) The adhesive liquid is mixed with the premixed dry powder and granulated to obtain the titanium dioxide masterbatch.

8. The preparation method according to claim 7, characterized in that, The adhesive liquid contains 5-15% polyvinylpyrrolidone by mass. Preferably, the mixing method in step (2) includes atomizing the adhesive liquid and spraying it onto the premixed dry powder; Preferably, the spraying rate is 2-4 mL / min.

9. The preparation method according to claim 7, characterized in that, The granulation method includes centrifugal shot blasting granulation; Preferably, the centrifugal shot blasting granulation is carried out at a rotation speed of 150-200 rpm; Preferably, the centrifugal shot blasting granulation time is 20-30 minutes; Preferably, the granulation process further includes a drying step. Preferably, the drying temperature is 50-70°C; Preferably, the drying process further includes a sieving step.

10. A water-based coating, characterized in that, The raw materials for preparing the water-based coating include titanium dioxide masterbatch as described in any one of claims 1-6.

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