Titanium dioxide slurry for water-based floating coat prepared by adopting MOFA dispersing and sanding process as well as preparation method and application of titanium dioxide slurry

Abstract

The invention discloses a titanium dioxide slurry for a water-based floating coat, which can be prepared by adopting an MOFA dispersing and sanding process, and a preparation method and an application of the titanium dioxide slurry. The titanium dioxide slurry is prepared from the following raw materials in parts by weight: 60 to 70 parts of titanium dioxide, 25 to 35 parts of water, 0.1 to 0.4 part of anti-settling aid, 0.15 to 0.35 part of pH regulator, 0.5 to 1 part of defoaming agent and 2 to 5 parts of wetting dispersant, wherein the water content of the titanium dioxide is 0-0.5%, the TiO2 content is greater than 95 wt%, the oil absorption is 17-23 g / 100 g, and the pH value is 6.5-9. According to the technical scheme, the problems that when the titanium dioxide slurry for the water-based floating coat is prepared by using an MOFA dispersing and sanding process, material absorption is difficult, the viscosity of the titanium dioxide slurry is too high, and the fineness is unqualified are solved.

Description

Technical Field

[0001] This invention relates to the field of water-based coating pigment technology. More specifically, it relates to a water-based titanium dioxide paste for intermediate coatings that can be prepared using the MOFA dispersion milling process, its preparation method, and its application. Background Technology

[0002] The working principle of traditional sand mills is mainly based on wet ultrafine sand milling technology. It uses the mechanical energy of the screw and grinding beads to refine the powder. First, wetting and dispersing agents and anti-settling agents are dissolved and dispersed in water. Then, the powder is wetted and dispersed in the water under high-speed stirring to achieve a uniform premixed slurry state. Finally, the premixed slurry is circulated and ground through the mechanical energy of the screw and grinding beads of the sand mill to achieve qualified parameters such as fineness, color, and gloss.

[0003] The MOFA dispersion milling process uses a specially designed rotor-stator system to generate a high vacuum, directly drawing in powder without dust or loss. Powder agglomerates are quickly broken down into fine particles, which are then directly wetted and dispersed by liquid under high shear. After a short high-shear cycle, the powder reaches the required fineness, color, gloss, and other parameters.

[0004] By eliminating the premixing process and shortening the milling time, the MOFA dispersion milling process greatly reduces production time (by up to 70%). Furthermore, the dust-free and loss-free transport and introduction of powder, wetting and dispersion to complete deagglomeration without lumps—all these steps are completed in one unit, reducing equipment footprint and energy costs, and avoiding dust pollution.

[0005] However, existing water-based intermediate coating titanium dioxide paste products are not suitable for the MOFA dispersion and milling process. This is mainly because using the MOFA dispersion and milling process to prepare existing water-based intermediate coating titanium dioxide pastes results in problems such as difficulty in material intake, excessively high titanium dioxide viscosity, and unqualified fineness, thus failing to meet subsequent production requirements. Summary of the Invention

[0006] Based on the above facts, the purpose of this invention is to provide an aqueous intermediate coating titanium dioxide paste that can be prepared using the MOFA dispersion and milling process, as well as its preparation method and application. The aqueous intermediate coating titanium dioxide paste provided in this invention is suitable for preparation using the MOFA dispersion and milling process.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] On one hand, the present invention provides an aqueous titanium dioxide paste for intermediate coating that can be prepared using the MOFA dispersion milling process, wherein, by weight, the raw materials forming the titanium dioxide paste contain:

[0009] 60-70 parts titanium dioxide, 25-35 parts water, 0.1-0.4 parts anti-settling agent, 0.15-0.35 parts pH adjuster, 0.5-1 part defoamer, and 2-5 parts wetting and dispersing agent;

[0010] The titanium dioxide has a water content of 0-0.5%, a TiO2 content of >95wt%, an oil absorption of 17-23g / 100g, and a pH value of 6.5-9.

[0011] Furthermore, the titanium dioxide is selected from one of rutile titanium dioxide R-996, LR-961 pigment, and titanium dioxide SR-237.

[0012] Furthermore, the anti-settling agent is selected from inorganic rheology modifiers; preferably LAPONITE RD or Hatorite RD.

[0013] Furthermore, the mass ratio of the titanium dioxide to the anti-settling agent is (250-270):1.

[0014] Furthermore, the pH adjuster is selected from dimethylethanolamine.

[0015] Furthermore, the defoamer is selected from at least one of SURFYNOL 104A additive, BYK-011 additive, and BYK-015 additive.

[0016] Furthermore, the wetting and dispersing agent is selected from... -DISPERSANT-190 polymer copolymer solution, -DISPERSANT-192 dispersant, JD-3190 and At least one of the 60J modified acrylic copolymers.

[0017] In another aspect, the present invention provides a method for preparing the water-based intermediate coating titanium dioxide paste as described above, which is prepared using a MOFA dispersion milling process. This preparation method includes the following steps:

[0018] The anti-settling agent was dispersed in a portion of water to obtain a uniform, particle-free, semi-transparent solution.

[0019] The pH adjuster, defoamer, and wetting and dispersing agent are added to the solution under stirring conditions to obtain a liquid material;

[0020] The titanium dioxide and liquid material are added to the MOFA dispersion mill, and after shearing and circulation, the remaining water is added to dilute the mixture, thus obtaining the water-based intermediate coating titanium dioxide paste.

[0021] In another aspect, the present invention provides an aqueous intermediate coating, wherein the raw materials for preparing the aqueous intermediate coating include the titanium dioxide paste for aqueous intermediate coating as described above.

[0022] In another aspect, the present invention provides the application of the water-based intermediate coating titanium dioxide paste as described above or the water-based intermediate coating titanium dioxide paste prepared by the preparation method as described above in the preparation of water-based intermediate coatings.

[0023] The beneficial effects of this invention are as follows:

[0024] The water-based intermediate coating titanium dioxide paste provided in this invention solves the problems of difficult material intake, excessively high viscosity, and unqualified fineness that occur when preparing water-based intermediate coating titanium dioxide paste using the MOFA dispersion milling process by selecting raw material components, controlling the amount of each component, and optimizing the process. Detailed Implementation

[0025] To more clearly illustrate the present invention, the following description, in conjunction with preferred embodiments, further clarifies the invention. Those skilled in the art should understand that the specific descriptions below are illustrative rather than restrictive, and should not be construed as limiting the scope of protection of the present invention.

[0026] To provide a water-based intermediate coating titanium dioxide paste suitable for MOFA dispersion milling process, avoiding problems such as material suction difficulties and dust pollution when preparing the titanium dioxide paste using the MOFA dispersion milling process, and ensuring that the fineness, gloss, viscosity, pH value, etc. of the water-based intermediate coating titanium dioxide paste prepared by the MOFA dispersion milling process meet the requirements, one specific embodiment of the present invention provides a water-based intermediate coating titanium dioxide paste that can be prepared by MOFA dispersion milling process, wherein, by weight, the raw materials forming the titanium dioxide paste include:

[0027] 60-70 parts titanium dioxide, 25-35 parts water, 0.1-0.4 parts anti-settling agent, 0.15-0.35 parts pH adjuster, 0.5-1 part defoamer, and 2-5 parts wetting and dispersing agent;

[0028] The titanium dioxide has a water content of 0-0.5%, a TiO2 content of >95wt%, an oil absorption of 17-23g / 100g, and a pH value of 6.5-9.

[0029] The choice of titanium dioxide affects the effectiveness of the MOFA dispersion milling process, such as the smoothness of material intake.

[0030] In some examples, the titanium dioxide is selected from one of rutile titanium dioxide R-996, LR-961 pigment, and titanium dioxide SR-237.

[0031] The water-based titanium dioxide paste for intermediate coatings provided in this embodiment can be efficiently produced using the MOFA dispersion and milling process. The MOFA dispersion and milling process significantly shortens production time, reduces energy consumption, increases the utilization rate of production space, and avoids dust pollution. The development of water-based titanium dioxide paste suitable for the MOFA dispersion and milling process promotes the application of this process in paint factory production, greatly improving factory production efficiency, reducing energy consumption, and responding to the national initiative for low-carbon and environmentally friendly production.

[0032] In some examples, the anti-settling agent is selected from inorganic rheology modifiers, preferably LAPONITE RD, Hatorite RD, etc. The choice of anti-settling agent affects the gloss and other properties of titanium dioxide paste prepared by MOFA dispersion milling process.

[0033] In some preferred examples, the mass ratio of titanium dioxide to anti-settling agent is (250-270):1. In this case, the MOFA dispersion milling process results in higher production efficiency and produces titanium dioxide paste with excellent appearance and gloss, making it highly suitable for water-based intermediate coats in automotive coatings.

[0034] In some examples, the pH adjuster is selected from dimethylethanolamine. The choice and amount of pH adjuster affect the viscosity and gloss of the resulting titanium dioxide paste.

[0035] In some examples, the defoamer is selected from at least one of SURFYNOL 104A additive, BYK-011 additive, and BYK-015 additive.

[0036] In some examples, the wetting and dispersing agent is selected from... -DISPERSANT-190 polymer copolymer solution, -Dispersant-192 dispersant, JD-3190 from Jiadian Chemical and At least one of the 60J modified acrylic copolymers.

[0037] In some examples, the total content of the raw materials is 100 parts.

[0038] According to another specific embodiment of the present invention, a method for preparing the aqueous intermediate coating titanium dioxide paste as described above is provided, wherein the preparation method is a MOFA dispersion and milling process. Specifically, the preparation method includes the following steps:

[0039] The anti-settling agent was dispersed in a portion of water to obtain a uniform, particle-free, semi-transparent solution.

[0040] The pH adjuster, defoamer, and wetting and dispersing agent are added to the solution under stirring conditions to obtain a liquid material;

[0041] The titanium dioxide and liquid material are added to the MOFA dispersion mill, and after shearing and circulation, the remaining water is added to dilute the mixture, thus obtaining the water-based intermediate coating titanium dioxide paste.

[0042] It is understood that the above-mentioned particle-free translucent solution is a solution that is visually transparent and free of particles.

[0043] According to another specific embodiment of the present invention, an aqueous intermediate coating is provided, wherein the raw materials for preparing the aqueous intermediate coating contain the titanium dioxide paste for aqueous intermediate coating as described above.

[0044] It is understandable that this water-based intermediate coat can be used as an intermediate coat in automotive painting.

[0045] According to another specific embodiment of the present invention, the application of the aqueous intermediate coating titanium dioxide paste or the aqueous intermediate coating titanium dioxide paste prepared by the preparation method described above in the preparation of aqueous intermediate coatings is provided.

[0046] The technical solution of the present invention will be described below with reference to some specific embodiments:

[0047] Example 1

[0048] A water-based titanium dioxide paste for intermediate coating that can be prepared using the MOFA dispersion milling process has the following raw material formulation as shown in Table 1.

[0049] The preparation method of the water-based intermediate coating titanium dioxide paste using the MOFA dispersion milling process includes the following steps:

[0050] 1) Disperse material 2 at high speed (3000 rpm, 5-10 min) into pure water (material 1) and mix evenly to obtain a uniform, particle-free, translucent solution;

[0051] 2) Add materials 3-6 to the solution obtained in step 1) in sequence while stirring, and stir evenly to form a liquid material;

[0052] 3) Vacuum-inhale material 7 into the MOFA dispersion mill, and then add the liquid material into the MOFA dispersion mill (wherein, the stirring parameters in the MOFA dispersion mill process are shown in Table 2). Under high shear, material 7 is wetted and dispersed by the liquid material. After a short high shear cycle, material 11 is added to dilute the mixture, and finally the water-based intermediate coating titanium dioxide paste is obtained.

[0053] Table 1

[0054]

[0055] Table 2

[0056]

[0057] Comparative Example 1

[0058] A water-based intermediate coating titanium dioxide paste, the raw material formula of which is shown in Table 1 above.

[0059] The preparation method of the water-based intermediate coating titanium dioxide paste using the MOFA dispersion milling process includes the following steps:

[0060] 1) Stir materials 1 and 3-6 evenly under stirring to form a liquid material;

[0061] 2) Vacuum-inhale materials 7 and 9 into the MOFA dispersion mill, and then add the liquid material into the MOFA dispersion mill (wherein, the stirring parameters in the MOFA dispersion mill process are shown in Table 2). Under high shear, material 7 is wetted and dispersed by the liquid material. After a short high shear cycle, material 11 is added to dilute the mixture, and the water-based intermediate coating titanium dioxide paste is obtained.

[0062] Comparative Example 2

[0063] A water-based intermediate coating titanium dioxide paste, the raw material formula of which is shown in Table 1 above.

[0064] The preparation method of the water-based intermediate coating titanium dioxide paste using the MOFA dispersion milling process includes the following steps:

[0065] 1) Disperse material 2 at high speed (3000 rpm, 5-10 min) into pure water (material 1) and mix evenly to obtain a uniform, particle-free, translucent solution;

[0066] 2) Add materials 3-6 in sequence while stirring, and stir evenly to form a liquid material;

[0067] 3) The material 8 is vacuum-inhaled into the MOFA dispersion mill, where it is wetted and dispersed by the liquid material under high shear. After a short period of high shear cycle, material 11 is added to dilute the mixture, and finally, water-based titanium dioxide paste for intermediate coating is obtained.

[0068] Comparative Example 3

[0069] A water-based intermediate coating titanium dioxide paste, the raw material formula of which is shown in Table 1 above.

[0070] The preparation method of the water-based intermediate coating titanium dioxide paste using the MOFA dispersion milling process includes the following steps:

[0071] 1) Disperse material 2 at high speed (3000 rpm, 5-10 min) into pure water (material 1) and mix evenly to obtain a uniform, particle-free, translucent solution;

[0072] 2) Add materials 3-6 in sequence while stirring, and stir evenly to form a liquid material;

[0073] 3) Vacuum-inhale material 7 into the MOFA dispersion mill, and then add the liquid material into the MOFA dispersion mill. Material 7 is wetted and dispersed by the liquid material under high shear. After a short period of high shear cycle, material 11 is added to dilute the mixture, and finally water-based intermediate coating titanium dioxide paste is obtained.

[0074] Comparative Example 4

[0075] A water-based intermediate coating titanium dioxide paste, the raw material formula of which is shown in Table 1 above.

[0076] The preparation method of the water-based intermediate coating titanium dioxide paste using the MOFA dispersion milling process includes the following steps:

[0077] 1) Disperse material 10 at high speed (3000 rpm, 5-10 min) into pure water (material 1) and mix evenly to obtain a uniform, particle-free, translucent solution;

[0078] 2) Add materials 3-6 to the solution obtained in step 1) in sequence while stirring, and stir evenly to form a liquid material;

[0079] 3) Vacuum-inhale material 7 into the MOFA dispersion mill, and then add the liquid material into the MOFA dispersion mill. Material 7 is wetted and dispersed by the liquid material under high shear. After a short period of high shear cycle, material 11 is added to dilute the mixture, and finally water-based intermediate coating titanium dioxide paste is obtained.

[0080] The performance test results of the titanium dioxide pastes prepared in Example 1 and Comparative Examples 1-4 are shown in Table 3 below.

[0081] Table 3

[0082]

[0083]

[0084] As shown in the table above, Example 1 meets the performance requirements of water-based intermediate coating titanium dioxide paste, with smooth powder intake and is suitable for MOFA dispersion and milling process.

[0085] In Comparative Example 1, the anti-settling additive LAPONITE RD is a flake-shaped silicate ultrafine powder. It is vacuum-inhaled into the MOFA dispersion mill along with the titanium dioxide. It cannot be well dispersed in the system, resulting in the titanium dioxide paste used in water-based intermediate coating having unqualified fineness. The anti-settling additive LAPONITE RD needs to be dispersed into pure water at high speed in advance before use.

[0086] In Comparative Example 2, vacuum suction of TIPAQUE CR-97 titanium dioxide powder into the MOFA dispersion mill caused the powder to be compacted and blocked at the suction port. Therefore, TIPAQUE CR-97 titanium dioxide could only be vacuum-suctioned into the MOFA dispersion mill in small amounts multiple times.

[0087] In Comparative Example 3, the viscosity of this water-based intermediate coating titanium dioxide paste is greatly affected by pH value. When the amount of dimethylethanolamine added is low, the pH is too low, the viscosity exceeds the required upper limit, and the 60° gloss is also too low.

[0088] In Comparative Example 4, the anti-settling agent was replaced with bentonite EW, which resulted in a 60° gloss level below the lower limit. The selection of anti-settling agents for water-based intermediate coating titanium dioxide paste in this system needs to take into account their impact on gloss.

[0089] Example 2-Example 3

[0090] A water-based intermediate coating titanium dioxide paste can be prepared using the MOFA dispersion milling process, and its raw material formulation is shown in Table 4 below.

[0091] The preparation method of the water-based intermediate coating titanium dioxide paste using the MOFA dispersion milling process includes the following steps:

[0092] 1) Disperse material 2 at high speed (3000 rpm, 5-10 min) into pure water (material 1) and mix evenly to obtain a uniform, particle-free, semi-transparent solution.

[0093] 2) Add materials 3-6 in sequence while stirring, and stir evenly to form a liquid material;

[0094] 3) Vacuum-inhale material 7 into the MOFA dispersion mill, and then add the liquid material into the MOFA dispersion mill (wherein, the stirring parameters in the MOFA dispersion mill process are shown in Table 2). Material 7 is wetted and dispersed by the liquid material under high shear. After a short period of high shear cycle, material 8 is added to dilute the mixture, and finally the water-based intermediate coating titanium dioxide paste is obtained.

[0095] Table 4

[0096]

[0097]

[0098] Comparative Examples 5-6

[0099] The raw material formula for water-based intermediate coating titanium dioxide paste is shown in Table 4.

[0100] The preparation method of the water-based intermediate coating titanium dioxide paste using the MOFA dispersion milling process includes the following steps:

[0101] 1) Disperse material 2 at high speed (3000 rpm, 5-10 min) into pure water (material 1) and mix evenly to obtain a uniform, particle-free, semi-transparent solution.

[0102] 2) Add materials 3-6 in sequence while stirring, and stir evenly to form a liquid material;

[0103] 3) Vacuum-inhale material 7 into the MOFA dispersion mill, and then add the liquid material into the MOFA dispersion mill (wherein, the stirring parameters in the MOFA dispersion mill process are shown in Table 2). Material 7 is wetted and dispersed by the liquid material under high shear. After a short period of high shear cycle, material 8 is added to dilute the mixture, and finally the water-based intermediate coating titanium dioxide paste is obtained.

[0104] The performance test results of the titanium dioxide pastes prepared in Examples 2-3 and Comparative Examples 5-6 are shown in Table 5 below.

[0105] Table 5

[0106]

[0107] As shown in the table above, Examples 2-3 meet the performance requirements of water-based intermediate coating titanium dioxide paste, with smooth powder intake and suitable for MOFA dispersion and milling process.

[0108] If the amount of anti-settling additive LAPONITE RD added in Comparative Examples 5-6 is too low or too high, the viscosity will be too low or too high, and the viscosity will not meet the requirements of the titanium dioxide paste, which will affect the stability and settling properties of the titanium dioxide paste.

[0109] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. For those skilled in the art, other variations or modifications can be made based on the above description. It is impossible to exhaustively list all the implementation methods here. All obvious variations or modifications derived from the technical solutions of the present invention are still within the protection scope of the present invention.

Claims

1. A water-based titanium dioxide paste for intermediate coating that can be prepared using the MOFA dispersion and milling process, characterized in that, The raw materials for forming the titanium dioxide paste, by weight, include: 60-70 parts titanium dioxide, 25-35 parts water, 0.1-0.4 parts anti-settling agent, 0.15-0.35 parts pH adjuster, 0.5-1 part defoamer, and 2-5 parts wetting and dispersing agent; The titanium dioxide has a water content of 0-0.5%, a TiO2 content of >95wt%, an oil absorption of 17-23g / 100g, and a pH value of 6.5-9.

2. The water-based titanium dioxide paste for intermediate coating according to claim 1, characterized in that, The titanium dioxide is selected from one of the following: rutile titanium dioxide R-996, LR-961 pigment, and titanium dioxide SR-237.

3. The water-based intermediate coating titanium dioxide paste according to claim 1, characterized in that, The anti-settling additive is selected from inorganic rheology modifiers; preferably LAPONITE RD or Hatorite RD.

4. The water-based titanium dioxide paste for intermediate coating according to any one of claims 1-3, characterized in that, The mass ratio of titanium dioxide to anti-settling agent is (250-270):

1.

5. The water-based intermediate coating titanium dioxide paste according to claim 1, characterized in that, The pH adjuster is selected from dimethylethanolamine.

6. The water-based intermediate coating titanium dioxide paste according to claim 1, characterized in that, The defoamer is selected from at least one of SURFYNOL104A additive, BYK-011 additive, and BYK-015 additive.

7. The water-based intermediate coating titanium dioxide paste according to claim 1, characterized in that, The wetting and dispersing agent is selected from... -DISPERSANT-190 polymer copolymer solution, -DISPERSANT-192 dispersant, JD-3190 and At least one of the 60J modified acrylic copolymers.

8. The method for preparing water-based intermediate coating titanium dioxide paste according to any one of claims 1-7, characterized in that, The material was prepared using a MOFA dispersion milling process, which includes the following steps: The anti-settling agent was dispersed in a portion of water to obtain a uniform, particle-free, semi-transparent solution. The pH adjuster, defoamer, and wetting and dispersing agent are added to the solution under stirring conditions to obtain a liquid material; The titanium dioxide and liquid material are added to the MOFA dispersion mill, and after shearing and circulation, the remaining water is added to dilute the mixture, thus obtaining the water-based intermediate coating titanium dioxide paste.

9. A water-based intermediate coating, characterized in that, The raw materials used to prepare the water-based intermediate coating include the titanium dioxide paste for water-based intermediate coating as described in any one of claims 1-7.

10. The application of the water-based intermediate coating titanium dioxide paste as described in any one of claims 1-7 or the water-based intermediate coating titanium dioxide paste prepared by the preparation method as described in claim 8 in the preparation of water-based intermediate coatings.

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