Method for depositing silicon dioxide through acid-base coordinated regulation and control

Abstract

The invention belongs to the technical field of inorganic coating and particle surface modification, and particularly discloses a method for depositing silicon dioxide through acid-base coordinated regulation and control, which comprises the following steps: S1, dispersing pre-dried organic pigment particles in ethanol, adding a surfactant and zirconium beads, and sanding; s2, adding sodium silicate in proportion, heating and stirring, and then raising the temperature; s3, adjusting the pH value of the reaction system A obtained in S2 to 3.5-5.5 by using an acid solution, and maintaining the reaction for 1-4 hours; s4, adjusting the pH value to 8-10 by using alkali liquor, and maintaining the reaction for 1-4 hours; and S5, cooling, performing centrifugal separation, and performing vacuum drying to obtain the organic pigment particles coated with the silicon dioxide shell layer. According to the method for depositing silicon dioxide through acid-base coordinated regulation and control, a SiO2 coating layer which is compact in structure and firm in adhesion is constructed on the surfaces of particles, and the controllability of the deposition process and the consistency of a deposition layer are remarkably improved.

Description

Technical Field

[0001] The present invention relates to the technical field of inorganic coating and particle surface modification, and particularly to a method for synergistically regulating and depositing silica by acid and base. Background Art

[0002] In the development process of functional particulate materials, the dispersibility, surface stability and subsequent modifiability of particles are the key factors determining their application performance. Especially in the fields of pigments, fillers, catalyst carriers and composite functional materials, the interfacial behavior of particles in the system directly affects the color uniformity, mechanical properties, storage stability and process adaptability of products.

[0003] Silica (SiO2) coating technology has received extensive attention in particle surface modification due to its high chemical stability, flexible interfacial regulation and ability to form a dense shell layer. In the prior art, the SiO2 deposition method often adopts an alkaline hydrolysis process, such as the method or the direct condensation method of sodium silicate under high pH conditions. However, when dealing with surface-inert, organic or structurally complex particles, these methods often have problems such as uneven coating, serious agglomeration and weak interfacial bonding, which limit their application in complex systems.

[0004] In recent years, in order to improve the density and controllability of the SiO2 deposition layer, some studies have tried to introduce a slow-release silicon source, a surface initiator or a multi-step regulation path, but there is still a lack of a general coating strategy with mild reaction conditions, uniform structure and strong adaptability. Therefore, it is urgent to develop a method that can efficiently regulate the hydrolysis-condensation kinetic process and achieve precise construction of the silica shell layer. Summary of the Invention

[0005] The purpose of the present invention is to provide a method for synergistically regulating and depositing silica by acid and base, so as to construct a dense and firmly attached SiO2 coating layer on the particle surface, and significantly improve the controllability of the deposition process and the uniformity of the deposition layer.

[0006] To achieve the above purpose, the present invention provides a method for synergistically regulating and depositing silica by acid and base, including the following steps:

[0007] S1. Dispersing pre-dried organic particles in ethanol, then adding a surfactant and zirconium beads, and performing sanding treatment to obtain a stable pigment dispersion;

[0008] S2. Adding sodium silicate to the pigment dispersion obtained in S1 in proportion, performing heating and stirring treatment to promote uniform dispersion and then raising the temperature to obtain reaction system A;

[0009] S3. Adjust the pH of the reaction system A obtained in S2 to 3.5 - 5.5 with an acid solution, and maintain the reaction for 1 - 4 h to control the hydrolysis rate of the silicon source, obtaining reaction system B;

[0010] S4. Adjust the pH of the reaction system B obtained in S3 to 8 - 10 with an alkali solution, and maintain the reaction for 1 - 4 h to accelerate the condensation reaction and deposit silica on the particle surface to form a coating layer, and the reaction ends;

[0011] S5. After the reaction ends, cool and centrifuge to obtain a solid product, and perform vacuum drying to obtain organic pigment particles coated with a silica shell layer.

[0012] Preferably, in S1, by mass parts, it includes the following components:

[0013] 1 part of organic particles, 10 - 20 parts of ethanol solvent, 0.1 - 0.5 part of surfactant, 5 - 20 parts of zirconium beads.

[0014] Preferably, the organic particles are colored organic pigment particles, and the colored organic pigment particles are one of Pigment Red 254, Pigment Red 202, Pigment Red 48:2, Pigment Red 49:2, Pigment Red 57:1, Pigment Yellow 151, Pigment Yellow 83 or Pigment Blue 15:3;

[0015] The surfactant is a cationic surfactant, and the cationic surfactant is one or more of cetyltrimethylammonium bromide, cetyltrimethylammonium chloride, dodecyltrimethylammonium bromide, dodecylpyridinium bromide or quaternary ammonium salt cationic surfactants.

[0016] Preferably, in S1, the sanding treatment is carried out using a sand mill, and the treatment time is 5 - 12 h.

[0017] Preferably, in S2, the addition amount of sodium silicate is 10 - 30 wt% of the mass of the organic particles.

[0018] Preferably, in S2, after the heating and stirring treatment, the temperature is raised to 50 °C and stirred for 2 h, and then raised to 70 °C.

[0019] Preferably, in S3, the acid solution is one of acetic acid, hydrochloric acid or sulfuric acid, and the concentration of the acid solution is 0.05 - 0.2 mol / L.

[0020] Preferably, in S4, the alkali solution is one of sodium hydroxide or ammonia water, and the concentration of the alkali solution is 0.05 - 1 mol / L.

[0021] Preferably, in S5, the temperature of the vacuum drying is 60 - 80 °C, and the time is 10 - 20 h.

[0022] Preferably, in S5, the preparation method of the solid product is as follows:

[0023] After the reaction is completed, the system is cooled to room temperature, and the precipitate is obtained by centrifugal separation at 5000 - 7000 rpm, and washed alternately with deionized water and absolute ethanol 3 - 5 times.

[0024] Therefore, the present invention adopts the above method for acid-base synergistic regulation of silica deposition, and the beneficial effects are as follows:

[0025] (1) The process conditions of the present invention are mild, the reaction system has strong stability, and the raw material cost is low. It is applicable to the inorganic coating of various particle systems, especially suitable for inorganic surface modification such as surface encapsulation, interface modification or subsequent coupling modification of pigment materials, providing a new technical path for the preparation of hybrid particle materials with high surface stability and high dispersibility, and having good generality and industrial application prospects.

[0026] (2) In the present invention, sodium silicate is first uniformly dispersed in the reaction system containing organic pigment particles and stirred at 50 °C to make it fully dispersed; then, by adding an appropriate amount of acid, the pH of the reaction system is adjusted to 3.5 - 5.5, so that sodium silicate slowly hydrolyzes under acidic conditions to generate a structurally stable silanol intermediate; then, at 70 °C, adding alkali to adjust the pH to 8 - 10 induces the condensation reaction of silanol, and gradually deposits on the particle surface to form a continuous and dense silica shell layer. The silica deposition method adopted is the water glass method of acid-base synergistic regulation, and by segmentally adjusting the pH value of the reaction system, the separation control of the hydrolysis and condensation processes of sodium silicate is realized.

[0027] (3) In the construction of the dispersion system of the present invention, a cationic surfactant (such as CTAC, CTAB, etc.) is selected and mixed with an ethanol solvent to form a highly stable pigment dispersion system under ball milling conditions, providing a good interfacial environment for the subsequent deposition of the silicon source.

[0028] (4) Through the pH segmental regulation mechanism of acid first and then alkali, the hydrolysis and condensation rates of sodium silicate are precisely adjusted, effectively realizing the decoupling of the time and rate of the hydrolysis and condensation reactions of the silicon source, significantly improving the structural uniformity and interfacial adaptability of the silica coating process, and avoiding the problems of uneven deposition and agglomeration caused by the simultaneous hydrolysis and condensation of sodium silicate under traditional single alkaline conditions; this regulation path helps to construct a uniform and continuous inorganic coating layer on the surface of complex particles, improve the compactness and integrity of the coating structure, and can significantly improve the dispersion stability, post-treatment compatibility and storage performance of pigment particles.

[0029] The technical solutions of the present invention will be further described in detail below with reference to the drawings and embodiments. Description of the Drawings

[0030] Figure 1 SEM image of Example 1 of the method for synergistically regulating the deposition of silica by acid and base according to the present invention;

[0031] Figure 2 TEM image of Example 1 of the method for synergistically regulating the deposition of silica by acid and base according to the present invention;

[0032] Figure 3 SEM image of Example 2 of the method for synergistically regulating the deposition of silica by acid and base according to the present invention;

[0033] Figure 4 TEM image of Example 2 of the method for synergistically regulating the deposition of silica by acid and base according to the present invention. Detailed implementation manners

[0034] The technical solutions of the present invention will be further described below with reference to the accompanying drawings and examples.

[0035] Unless otherwise defined, the technical terms or scientific terms used in the present invention shall have the ordinary meanings understood by those of ordinary skill in the field to which the present invention belongs.

[0036] Example 1

[0037] A method for synergistically regulating the deposition of silica by acid and base, comprising the following steps:

[0038] S1. Take 3 g of pre-dried pigment red 254 sample, add it to 30 mL of ethanol solvent, then add 0.3 g of cetyltrimethylammonium bromide (CTAB) and 10 g of zirconium beads with a diameter of 2 mm, and grind in a sand mill for 12 h to obtain a stable pigment dispersion.

[0039] S2. Transfer the pigment dispersion to a 500 mL four-necked flask, heat it to 50 °C under mechanical stirring, add 0.6 g of sodium silicate (20 wt% of the pigment mass), and continue stirring for 2 h to promote uniform dispersion. Then heat it to 70 °C, slowly dropwise add 0.1 mol / L acetic acid solution to adjust the pH of the reaction system to 4.5, and maintain this condition for reaction for 2 h to control the hydrolysis rate of the silicon source; then slowly dropwise add 0.1 mol / L sodium hydroxide solution to adjust the pH to 9, and continue the reaction for 3 h to promote the condensation reaction and deposit silica on the particle surface to form a coating layer. After the reaction is completed, cool the system to room temperature, centrifuge at 6000 rpm to obtain a precipitate, and wash it 3 times alternately with deionized water and absolute ethanol. Place the washed sample in a vacuum drying oven and dry it at 60 °C for 12 h to finally obtain pigment red 254 particles A with a uniformly coated SiO2 on the surface.

[0040] Example 2

[0041] A method for synergistically regulating the deposition of silica by acid and base, comprising the following steps:

[0042] Prepare the pigment dispersion liquid, which is the same as S1 in Example 1.

[0043] S2. Transfer the pigment dispersion liquid to a 500 mL four-necked flask, heat it to 50 °C under mechanical stirring, add 0.9 g of sodium silicate (30 wt% of the pigment mass), and continue stirring for 2 h. Then heat it to 70 °C, slowly dropwise add 0.1 mol / L sulfuric acid solution to adjust the pH of the reaction system to 4.5, and maintain this condition for reaction for 2 h; then slowly dropwise add 0.1 mol / L sodium hydroxide solution to adjust the pH to 9, and continue reacting for 3 h to promote the condensation reaction. After the reaction is completed, cool the system to room temperature, obtain the precipitate by centrifugation at 6000 rpm, and wash it alternately with deionized water and absolute ethanol 3 times. Place the washed sample in a vacuum drying oven and dry it at 60 °C for 12 h to finally obtain Pigment Red 254 particles B with uniformly coated SiO2 on the surface.

[0044] Example 3

[0045] A method for synergistically regulating the deposition of silicon dioxide by acid and base, comprising the following steps:

[0046] Prepare the pigment dispersion liquid, which is the same as S1 in Example 1.

[0047] S2. Transfer the pigment dispersion liquid to a 500 mL four-necked flask, heat it to 50 °C under mechanical stirring, add 0.3 g of sodium silicate (10 wt% of the pigment mass), and continue stirring for 2 h. Then heat it to 70 °C, slowly dropwise add 0.1 mol / L acetic acid solution to adjust the pH of the reaction system to 4.5, and maintain this condition for reaction for 2 h; then slowly dropwise add 0.1 mol / L sodium hydroxide solution to adjust the pH to 9, and continue reacting for 3 h to promote the condensation reaction. After the reaction is completed, cool the system to room temperature, obtain the precipitate by centrifugation at 6000 rpm, and wash it alternately with deionized water and absolute ethanol 3 times. Place the washed sample in a vacuum drying oven and dry it at 60 °C for 12 h to finally obtain Pigment Red 254 particles C with uniformly coated SiO2 on the surface.

[0048] Example 4

[0049] A method for synergistically regulating the deposition of silicon dioxide by acid and base, comprising the following steps:

[0050] Prepare the pigment dispersion liquid, which is the same as S1 in Example 1.

[0051] S2. Transfer the pigment dispersion to a 500 mL four-necked flask. Under mechanical stirring, heat it up to 50 °C, add 0.6 g of sodium silicate (20 wt% of the pigment mass), and continue stirring for 2 h. Then heat it up to 70 °C, slowly add 0.1 mol / L hydrochloric acid solution to adjust the pH of the reaction system to 4.5, and maintain this condition for reaction for 2 h; then slowly add 0.1 mol / L sodium hydroxide solution to adjust the pH to 9, and continue reacting for 3 h to promote the condensation reaction. After the reaction is completed, cool the system to room temperature, obtain the precipitate by centrifugation at 6000 rpm, and wash it alternately with deionized water and absolute ethanol 3 times. Place the washed sample in a vacuum drying oven and dry it at 60 °C for 12 h to finally obtain pigment red 254 particles D with a uniformly coated SiO2 surface.

[0052] Example 5

[0053] A method for synergistically regulating the deposition of silica by acid and base, comprising the following steps:

[0054] Prepare a pigment dispersion, which is the same as S1 in Example 1.

[0055] S2. Transfer the pigment dispersion to a 500 mL four-necked flask. Under mechanical stirring, heat it up to 50 °C, add 0.6 g of sodium silicate (20 wt% of the pigment mass), and continue stirring for 2 h. Then heat it up to 70 °C, slowly add 0.1 mol / L sulfuric acid solution to adjust the pH of the reaction system to 4.5, and maintain this condition for reaction for 2 h; then slowly add 0.1 mol / L sodium hydroxide solution to adjust the pH to 9, and continue reacting for 3 h to promote the condensation reaction. After the reaction is completed, cool the system to room temperature, obtain the precipitate by centrifugation at 6000 rpm, and wash it alternately with deionized water and absolute ethanol 3 times. Place the washed sample in a vacuum drying oven and dry it at 60 °C for 12 h to finally obtain pigment red 254 particles E with a uniformly coated SiO2 surface.

[0056] Example 6

[0057] A method for synergistically regulating the deposition of silica by acid and base, comprising the following steps:

[0058] S1. Take 3 g of a pre-dried pigment yellow 83 sample, add it to 30 mL of ethanol solvent, then add 0.3 g of cetyltrimethylammonium bromide (CTAB) and 10 g of zirconium beads with a diameter of 2 mm, and grind it in a sand mill for 12 h to obtain a stable pigment dispersion.

[0059] S2. Transfer the pigment dispersion to a 500 mL four-necked flask, heat it to 50 °C under mechanical stirring, add 0.6 g of sodium silicate (20 wt% of the pigment mass), and continue stirring for 2 h. Then heat it to 70 °C, slowly add 0.1 mol / L acetic acid solution to adjust the pH of the reaction system to 4.5, and maintain this condition for 2 h; then slowly add 0.1 mol / L sodium hydroxide solution to adjust the pH to 9, and continue reacting for 3 h to promote the condensation reaction. After the reaction is completed, cool the system to room temperature, obtain the precipitate by centrifugation at 6000 rpm, and wash it alternately with deionized water and absolute ethanol 3 times. Place the washed sample in a vacuum drying oven and dry it at 60 °C for 12 h to finally obtain pigment red 83 particles F with a uniformly coated SiO2 surface.

[0060] Example VII

[0061] A method for acid-base synergistic regulation of silicon dioxide deposition, comprising the following steps:

[0062] S1. Take 3 g of pre-dried pigment red 254 sample, add it to 30 mL of ethanol solvent, add 0.3 g of cetyltrimethylammonium chloride (CTAC) and 10 g of zirconium beads with a diameter of 2 mm, and grind it in a sand mill for 12 h to obtain a stable pigment dispersion.

[0063] S2. Transfer the pigment dispersion to a 500 mL four-necked flask, heat it to 50 °C under mechanical stirring, add 0.6 g of sodium silicate (20 wt% of the pigment mass), and continue stirring for 2 h. Then heat it to 70 °C, slowly add 0.1 mol / L acetic acid solution to adjust the pH of the reaction system to 4.5, and maintain this condition for 2 h; then slowly add 0.1 mol / L sodium hydroxide solution to adjust the pH to 9, and continue reacting for 3 h to promote the condensation reaction. After the reaction is completed, cool the system to room temperature, obtain the precipitate by centrifugation at 6000 rpm, and wash it alternately with deionized water and absolute ethanol 3 times. Place the washed sample in a vacuum drying oven and dry it at 60 °C for 12 h to finally obtain pigment red 254 particles G with a uniformly coated SiO2 surface.

[0064] Example VIII

[0065] A method for acid-base synergistic regulation of silicon dioxide deposition, comprising the following steps:

[0066] S1. Take 3 g of pre-dried pigment red 254 sample, add it to 30 mL of ethanol solvent, add 0.3 g of cetyltrimethylammonium chloride (CTAC) and 10 g of zirconium beads with a diameter of 2 mm, and grind it in a sand mill for 12 h to obtain a stable pigment dispersion.

[0067] S2. Transfer the pigment dispersion to a 500 mL four-necked flask, heat it to 50 °C under mechanical stirring, add 0.6 g of sodium silicate (20 wt% of the pigment mass), and continue stirring for 2 h. Then heat it to 70 °C, slowly add 0.1 mol / L acetic acid solution to adjust the pH of the reaction system to 4.5, and maintain this condition for 2 h; then slowly add 0.1 mol / L sodium hydroxide solution to adjust the pH to 9, and continue reacting for 3 h to promote the condensation reaction. After the reaction is completed, cool the system to room temperature, obtain the precipitate by centrifugation at 6000 rpm, and wash it alternately with deionized water and absolute ethanol 3 times. Place the washed sample in a vacuum drying oven and dry it at 80 °C for 12 h to finally obtain pigment red 254 particles H with a uniformly coated SiO2 surface.

[0068] Example IX

[0069] A method for synergistically regulating the deposition of silica by acid and base, comprising the following steps:

[0070] S1. Take 3 g of pre-dried pigment red 254 sample, add it to 30 mL of ethanol solvent, add 0.3 g of cetyltrimethylammonium chloride (CTAC) and 10 g of zirconium beads with a diameter of 2 mm, and grind it in a sand mill for 12 h to obtain a stable pigment dispersion.

[0071] S2. Transfer the pigment dispersion to a 500 mL four-necked flask, heat it to 50 °C under mechanical stirring, add 0.6 g of sodium silicate (20 wt% of the pigment mass), and continue stirring for 2 h. Then heat it to 70 °C, slowly add 0.1 mol / L acetic acid solution to adjust the pH of the reaction system to 6, and maintain this condition for 2 h; then slowly add 0.1 mol / L sodium hydroxide solution to adjust the pH to 9, and continue reacting for 3 h to promote the condensation reaction. After the reaction is completed, cool the system to room temperature, obtain the precipitate by centrifugation at 6000 rpm, and wash it alternately with deionized water and absolute ethanol 3 times. Place the washed sample in a vacuum drying oven and dry it at 80 °C for 12 h to finally obtain pigment red 254 particles I with a uniformly coated SiO2 surface.

[0072] Example X

[0073] A method for synergistically regulating the deposition of silica by acid and base, comprising the following steps:

[0074] S1. Take 3 g of pre-dried pigment red 254 sample, add it to 30 mL of ethanol solvent, add 0.3 g of cetyltrimethylammonium chloride (CTAC) and 10 g of zirconium beads with a diameter of 2 mm, and grind it in a sand mill for 12 h to obtain a stable pigment dispersion.

[0075] S2. Transfer the pigment dispersion to a 500 mL four-necked flask, heat it to 50 °C under mechanical stirring, add 0.6 g of sodium silicate (20 wt% of the pigment mass), and continue stirring for 2 h. Subsequently, heat it to 70 °C, slowly add 0.1 mol / L acetic acid solution dropwise to adjust the pH of the reaction system to 5, and maintain this condition for 2 h of reaction; then slowly add 0.1 mol / L sodium hydroxide solution dropwise to adjust the pH to 10, and continue the reaction for 3 h to promote the condensation reaction. After the reaction is completed, cool the system to room temperature, obtain the precipitate by centrifugation at 6000 rpm, and wash it alternately with deionized water and absolute ethanol three times. Place the washed sample in a vacuum drying oven and dry it at 80 °C for 12 h to finally obtain the pigment red 254 particles J with a uniformly coated SiO2 surface.

[0076] Test and measurement

[0077] Use the particles obtained in Examples 1 to 10 respectively for structure testing.

[0078] 1. Take Example 1 as an example, the test method is as follows:

[0079] Disperse 25 mg of pigment red 254 particles A in 12 mL of absolute ethanol, and use an ultrasonic cleaner to oscillate for 30 min to obtain a dispersion with uniformly dispersed particles.

[0080] Take an appropriate amount of the dispersion and drop it on the surface of a clean and dry silicon wafer or copper sheet, and let it stand and volatilize until completely dry to ensure that the sample adheres evenly. Subsequently, use an ion coater to perform gold plating treatment on the sample to enhance the surface conductivity. Observe the surface morphology of the sample using a scanning electron microscope (SEM, model: Regulus8100).

[0081] Take another 10 μL of the dispersion, use a micropipette to drop it on the surface of a carbon film copper grid (300 mesh), and let it stand and dry naturally. Use a transmission electron microscope (TEM, model: JEM-F200) for imaging.

[0082] 2. Test results:

[0083] The SEM test results show that silica deposition has occurred on the surfaces of the particles obtained in Examples 1 to 10. The SEM image of the pigment red 254 particles A obtained in Example 1 is as Figure 1 shown, and the SEM image of the pigment red 254 particles B obtained in Example 2 is as Figure 3 shown.

[0084] The TEM test results show that there may be instability in the surface deposition process of the particles obtained in Examples 1 to 10. The TEM image of the pigment red 254 particles A obtained in Example 1 is as Figure 2 shown, and the TEM image of the pigment red 254 particles B obtained in Example 2 is asFigure 4 as shown

[0085] 3. Result analysis:

[0086] It can be seen from Figure 1 that the particle dispersion of the displayed pigment red 254 particles A is good, the particle surface is significantly roughened, showing granular protrusions or local microstructural undulations, indicating that silica deposition has occurred on the particle surface. The overall particle size is uniform, and there is no obvious agglomeration between particles, and the deposition process is well controlled.

[0087] It can be seen from Figure 2 that the coating layer structure is observed around the pigment red 254 particles A, and the thickness is approximately 10 nm. The morphology of this coating layer is regular and the boundary is clear, which can better coat the core pigment particles to form a continuous SiO2 shell layer. The TEM image further verifies that Figure 1 the surface roughening observed in

[0088] is due to SiO2 deposition. In summary, it shows that: the uniform and dense silica coating of the pigment red 254 particles A is successfully achieved, the shell layer structure is continuous, and the deposition reaction process is controlled, indicating that the pH strategy of using acetic acid to adjust the hydrolysis stage has a good structure construction effect.

[0089] It can be seen from Figure 3 that the surface of the pigment red 254 particles B also shows a rough structure, but compared with Figure 1 , the local surface morphology is irregular, there is a stacking trend between particles, and there may be partial agglomeration in some areas. The uneven distribution of surface roughness indicates that the deposition process on the particle surface may be unstable.

[0090] It can be seen from Figure 4 that it shows that there is a discontinuous shell layer structure around some particles, the shell layer thickness changes significantly, the coating layer is thick in some areas and almost no coating in some areas, the edge is blurred, and the structural consistency is poor. It is consistent with the SEM observation results in Figure 3 , indicating that the reaction uniformity during the silica deposition process is poor and the coating structure defects are relatively prominent.

[0091] The above comparison shows that: although the silica deposition is achieved for the pigment red 254 particles B, the integrity and thickness uniformity of the shell layer structure are significantly inferior to those of the particles A, further indicating that within the same pH regulation range, the selected acid type (such as sulfuric acid) has a weak control force on the hydrolysis-condensation process, and the deposition behavior is easily disturbed by local conditions, affecting the final coating effect.

[0092] Therefore, the present invention adopts the above method of synergistically regulating the deposition of silica by acid and base to achieve the construction of a dense and firmly attached SiO2 coating layer on the particle surface, significantly improving the controllability of the deposition process and the consistency of the deposition layer.

[0093] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that they can still modify or equivalently replace the technical solutions of the present invention, and these modifications or equivalent replacements do not make the modified technical solutions deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for synergistically regulating the deposition of silica by acid and base, characterized in that, It includes the following steps: S1. Disperse the pre-dried organic particles in ethanol, then add a surfactant and zirconium beads, and perform sand grinding treatment to obtain a pigment dispersion; S2. Add sodium silicate to the pigment dispersion obtained in S1 in proportion, perform heating and stirring treatment and then raise the temperature to obtain reaction system A; S3. Use an acid solution to adjust the pH of reaction system A obtained in S2 to 3.5 - 5.5, and maintain the reaction for 1 - 4 h to obtain reaction system B; S4. Use an alkali solution to adjust the pH of reaction system B obtained in S3 to 8 - 10, and maintain the reaction for 1 - 4 h, and the reaction ends; S5. After the reaction ends, cool and perform centrifugal separation to obtain a solid product, and perform vacuum drying to obtain organic pigment particles coated with a silica shell layer.

2. The method for synergistically regulating the deposition of silica by acid-base as claimed in claim 1, wherein, In S1, by mass parts, it includes the following components: 1 part of organic particles, 10 - 20 parts of ethanol solvent, 0.1 - 0.5 part of surfactant, 5 - 20 parts of zirconium beads.

3. The method for co - regulating the deposition of silica by acid - base as claimed in claim 2, wherein, The organic particles are colored organic pigment particles, and the colored organic pigment particles are one of pigment red 254, pigment red 202, pigment red 48:2, pigment red 49:2, pigment red 57:1, pigment yellow 151, pigment yellow 83 or pigment blue 15:3; The surfactant is a cationic surfactant, and the cationic surfactant is one or more of cetyltrimethylammonium bromide, cetyltrimethylammonium chloride, dodecyltrimethylammonium bromide, dodecylpyridinium bromide or quaternary ammonium salt cationic surfactants.

4. A method for co - regulating the deposition of silica by acid - base, according to claim 1, characterized in that, In S1, the sand grinding treatment is carried out using a sand mill, and the treatment time is 5 - 12 h.

5. A method for co - regulating the deposition of silica by acid - base, according to claim 1, characterized in that, In S2, the addition amount of sodium silicate is 10 - 30 wt% of the mass of the organic particles.

6. A method for synergistically regulating the deposition of silica by acid and base, as claimed in claim 1, wherein In S2, after the heating and stirring treatment, the temperature is raised to 70 °C after stirring at 50 °C for 2 h.

7. A method for synergistically regulating the deposition of silica by acid and base according to claim 1, characterized in that, In S3, the acid solution is one of acetic acid, hydrochloric acid or sulfuric acid, and the concentration of the acid solution is 0.05 - 0.2 mol / L.

8. A method for co - regulating the deposition of silica by acid - base, according to claim 1, characterized in that, In S4, the alkali solution is one of sodium hydroxide or ammonia water, and the concentration of the alkali solution is 0.05 - 1 mol / L.

9. The method for co - regulating the deposition of silica by acid - base as claimed in claim 1, wherein, In S5, the temperature of the vacuum drying is 60 - 80 °C, and the time is 10 - 20 h.

10. A method for depositing silica by acid-base synergistic regulation according to claim 1, characterized in that, In S5, the preparation method of the solid product is: After the reaction ends, cool the system to room temperature, perform centrifugal separation at 5000 - 7000 rpm to obtain a precipitate, and wash it alternately with deionized water and absolute ethanol for 3 - 5 times.

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