High-stability grinding and polishing solution and preparation method thereof

Abstract

The invention relates to the field of 3C electronic product polishing solutions, and discloses a high-stability grinding and polishing solution and a preparation method thereof. The invention relates to a high-stability grinding and polishing solution which is prepared from the following raw materials in percentage by weight: 35-45% of silicon dioxide, 15-25% of organic silicon modified polyurethane emulsion, 10-15% of a grease stabilizer, 5-8% of a dispersing agent, 3.8-5.8% of an emulsifier, 2-4% of a complexing agent, 0.1-0.3% of a preservative and the balance of water. The grease stabilizer is prepared from zinc diricinoleate, diisostearyl malate and polyglycerol-10 myristate; the preparation method comprises the following steps: dissolving the complexing agent in water, adding the organic silicon modified polyurethane emulsion, the grease stabilizer, the dispersing agent and the emulsifier, heating and emulsifying to prepare an emulsion; adding silicon dioxide into the emulsion, and stirring and dispersing; the prepared grinding and polishing solution has relatively good long-term polishing stability, is not easy to generate scratches after being continuously used, and has good glossiness.

Description

Technical Field

[0001] This application relates to the field of polishing liquids for 3C electronic products. More specifically, it relates to a highly stable grinding and polishing liquid and a preparation method thereof. Background Art

[0002] Grinding and polishing liquids are widely used in the field of 3C electronic products, such as mobile phone back panels, mobile phone middle frames, computer casings, etc. In the processing technology, mechanical polishing technology is usually required to improve the surface topography to meet the requirements of subsequent surface treatment processes such as electroplating and painting. Such products have lower requirements for the glossiness and micro-geometric accuracy of the polished surface than optical or decorative precision components, but need to take into account the processing efficiency of continuous cyclic use, cost controllability, environmental protection, etc.

[0003] Existing grinding and polishing liquids applied to 3C electronic products are generally prepared from auxiliaries such as waterborne polyurethane resin, waterborne acrylic resin, abrasives, dispersants, surfactants, defoamers, etc., and have good polishing performance.

[0004] In the process of continuous operation of this type of grinding and polishing liquid, the continuous operation effect is not good. After using for a period of time, problems such as the deterioration of the grinding effect and scratches on the surface of the polished product will occur. In the actual production process, the consumption of grinding and polishing liquid in the grinding and polishing process is very large. If the waste liquid is directly recycled for treatment, the cost of waste liquid treatment will increase, and the waste of grinding and polishing liquid resources will be caused to a great extent. Therefore, the existing grinding and polishing liquid needs to be further improved. Summary of the Invention

[0005] In order to solve the problems that the existing grinding and polishing liquid applied to 3C electronic products is prone to problems such as the deterioration of the grinding effect and scratches on the surface of the polished product during continuous operation, this application provides a highly stable grinding and polishing liquid and a preparation method thereof.

[0006] In the first aspect, this application provides a highly stable grinding and polishing liquid, adopting the following technical solution: A highly stable grinding and polishing liquid is prepared from the following raw materials by weight percentage: Silica 35 - 45% Organosilicon-modified polyurethane emulsion 15 - 25% Oil stabilizer 10 - 15% Dispersant 5 - 8% Emulsifier 3.8 - 5.8% Complexing agent 2 - 4% Preservative 0.1 - 0.3% The balance is water; The oil stabilizer is composed of zinc ricinoleate, diisostearyl malate and polyglyceryl-10 myristate.

[0007] By adopting the above technical solution, using silica as the abrasive, it can directly grind and polish 3C electronic products, such as the backplane and middle frame of mobile phones, etc., effectively improving their surface topography, with good polishing efficiency; the organosilicon-modified polyurethane emulsion can improve the stability and flexibility of the grinding and polishing liquid, making the polishing process smoother, reducing the friction of the dioxide slide rail, and thus reducing the problem of scratches; the grease stabilizer composed of zinc ricinoleate, diisostearyl malate and polyglyceryl-10 myristate helps to maintain the stability of the system and improve the dispersion uniformity of silica in the organosilicon-modified polyurethane emulsion; the dispersant can further cooperate with the grease stabilizer to make silica evenly dispersed in the system, avoid agglomeration, and improve the consistency of grinding efficiency and polishing effect; the emulsifier can make the organic phase and the aqueous phase mix better to form a stable emulsion structure; the complexing agent can complex with metal ions to reduce the influence of impurities on the grinding and polishing process; the preservative can inhibit the growth of microorganisms and prevent the grinding and polishing liquid from deteriorating. Each raw material cooperates with each other and acts synergistically, making the grinding and polishing liquid have high stability, being able to maintain a good grinding effect for a long time during continuous operation, avoiding scratches on the surface of the polished product, having good gloss, having good recyclability, long service life, reducing the generation amount and treatment cost of waste liquid, and improving the resource utilization rate.

[0008] Preferably, the grease stabilizer is composed of zinc ricinoleate, diisostearyl malate and polyglyceryl-10 myristate in a weight ratio of 1:(2 - 3):(0.4 - 0.8).

[0009] By adopting the above technical solution, zinc ricinoleate has good lubricity and anti-wear properties, and can reduce the friction during the grinding process; diisostearyl malate has excellent emulsification stability and dispersibility, which can evenly disperse the components in the grinding and polishing liquid, prevent particle agglomeration, and improve the uniformity of grinding; polyglyceryl-10 myristate has good thickening and foam stabilizing effects, and helps to maintain the stability and foam characteristics of the grinding and polishing liquid. The three are composed into a grease stabilizer in a weight ratio of 1:(2 - 3):(0.4 - 0.8) and applied to the grinding and polishing liquid, which can uniformly form a continuous and uniform oil film on the surface of silica, improve the dispersion uniformity and lubrication performance of silica during continuous operation, and then synergistically enhance the stability of the grinding and polishing liquid, avoid the problems of poor grinding effect and scratches on the surface of the polished product, have good gloss, and the prepared grinding and polishing liquid has good recyclability.

[0010] Preferably, the dispersant is composed of 1,4-butanediol dimethacrylate and methyl vinyl ether / maleic anhydride copolymer in a weight ratio of 1:(1 - 2).

[0011] By adopting the above technical solutions, 1,4-butanediol dimethacrylate has good dispersibility and wetting properties, which can evenly disperse each raw material and avoid agglomeration; the methyl vinyl ether / maleic anhydride copolymer has strong adsorption and stability, which can enhance the stability of the system. The two are combined as a dispersant in a weight ratio of 1:(1-2) for use in the abrasive polishing liquid, and can play a synergistic role, further synergizing with the oil stabilizer to improve the continuity and stability of the coated oil film, thereby enabling the abrasive polishing liquid to maintain good polishing effects during continuous cyclic operation, reducing the generation of scratches on the surface of the polished product, and having good gloss.

[0012] Preferably, the emulsifier is composed of glycerol / inulin lauryl carbamate and polyoxyethylene sorbitan ester in a weight ratio of 1:(2.5-3.5).

[0013] By adopting the above technical solutions, glycerol / inulin lauryl carbamate and polyoxyethylene sorbitan ester act synergistically as an emulsifier in a weight ratio of 1:(2.5-3.5), which can make each component in the abrasive polishing liquid mix more evenly, improve the stability of the emulsion, reduce the separation of the oil phase and the water phase, thereby ensuring the stability of the abrasive polishing liquid during continuous cyclic operation and avoiding problems such as a deteriorated polishing effect and scratches on the surface of the polished product.

[0014] Preferably, the particle size of the silica is 50-100 nm.

[0015] By adopting the above technical solutions, selecting silica with a particle size of 50-100 nm can effectively improve the polishing uniformity of the abrasive polishing liquid for 3C electronic products, and reduce problems such as low polishing efficiency due to too fine particle size or uneven polishing due to too large particle size.

[0016] Preferably, the complexing agent is any one or combination of sodium citrate, disodium ethylenediaminetetraacetate, and sodium gluconate.

[0017] By adopting the above technical solutions, selecting any one or combination of sodium citrate, disodium ethylenediaminetetraacetate, and sodium gluconate as the complexing agent can undergo a complexation reaction with metal ions in the abrasive polishing liquid, reduce the interference of metal ions on the polishing process, improve the chemical stability of the abrasive polishing liquid, and thereby ensure the stability of the polishing effect.

[0018] Preferably, the preservative is methylisothiazolinone and / or 1,2-benzisothiazolin-3-one.

[0019] By adopting the above technical solution, methylisothiazolinone and / or 1,2-benzisothiazolin-3-one are added as preservatives to the grinding and polishing fluid, which can effectively inhibit the growth and reproduction of microorganisms, prevent the grinding and polishing fluid from deteriorating due to microbial contamination or temperature change during continuous use, extend the service life of the grinding and polishing fluid, and maintain its stable performance.

[0020] In a second aspect, the present application provides a method for preparing a highly stable grinding and polishing fluid, adopting the following technical solution: A method for preparing a highly stable grinding and polishing fluid includes the following steps: S1. Dissolve a complexing agent in water, and then add an organosilicon-modified polyurethane emulsion, an oil stabilizer, a dispersant, and an emulsifier for heating and emulsification to obtain an emulsion. S2. Add silicon dioxide to the emulsion and stir to disperse it to obtain a highly stable grinding and polishing fluid.

[0021] By adopting the above technical solution, first dissolving the complexing agent in water can fully disperse the complexing agent in the aqueous phase; then adding the organosilicon-modified polyurethane emulsion, the oil stabilizer, the dispersant, and the emulsifier for heating and emulsification, the heating process promotes the interaction between the molecules of each component, making these components evenly dispersed in the system to form a stable emulsification structure, and the obtained emulsion has good stability; then adding silicon dioxide to the emulsion and stirring to disperse it, so that the silicon dioxide is evenly distributed in the emulsion system, ensuring the uniformity and stability of the entire grinding and polishing fluid system, and finally obtaining a grinding and polishing fluid with high system stability.

[0022] Preferably, the heating temperature in step S1 is 60-80°C, and the time is 1-2 h.

[0023] By adopting the above technical solution, controlling the temperature at 60-80°C and the time at 1-2 h can enable the complexing agent, the organosilicon-modified polyurethane emulsion, the oil stabilizer, the dispersant, and the emulsifier to fully carry out heating and emulsification, which is beneficial to forming a uniform and stable emulsion, and further ensuring the stable performance of the finally obtained highly stable grinding and polishing fluid.

[0024] Preferably, the stirring rate in step S2 is 800-1200 r / min.

[0025] By adopting the above technical solution, controlling the stirring rate in step S2 at 800-1200 r / min, this stirring rate can fully disperse the silicon dioxide in the emulsion, ensure the uniform distribution of each component, and further improve the overall stability of the grinding and polishing fluid.

[0026] In summary, the present application includes at least one of the following beneficial technical effects: 1. The high-stability grinding and polishing fluid of the present application is prepared from silicon dioxide, organosilicon-modified polyurethane emulsion, grease stabilizer, dispersant, emulsifier, complexing agent, preservative and water. Silicon dioxide is used as an abrasive, and the compounding of organosilicon-modified polyurethane emulsion helps to improve the stability and adhesion of the grinding and polishing fluid; the grease stabilizer is composed of zinc ricinoleate, diisostearyl malate and polyglyceryl-10 myristate, which can maintain the stability of the grinding and polishing fluid; various raw materials interact synergistically to enhance the stability of the continuous circulation operation of the grinding and polishing fluid, solve the problems of deteriorated grinding effect and scratches on the surface of polished products during continuous operation, have good gloss, long service life, reduce the generation amount and treatment cost of waste liquid, and improve the resource utilization rate.

[0027] 2. The dispersant is composed of 1,4-butanediol dimethacrylate and methyl vinyl ether / maleic anhydride copolymer in a weight ratio of 1:(1-2), which can evenly disperse the components in the grinding and polishing fluid, avoid particle agglomeration, and thus improve the grinding efficiency and the stability of the circulation operation.

[0028] 3. The emulsifier is composed of inulin lauryl carbamate and polyoxyethylene sorbitan ester in a weight ratio of 1:(2.5-3.5), which can better mix the oil phase and the water phase to form a stable emulsion system, and improve the stability and uniformity of the grinding and polishing fluid.

[0029] 4. The preparation method of the present application is to first dissolve the complexing agent in water, add the organosilicon-modified polyurethane emulsion, grease stabilizer, dispersant and emulsifier to further emulsify to obtain an emulsion, and then add silicon dioxide and stir and disperse. Through step-by-step operation, each raw material can fully react and mix, ensuring the quality and performance of the grinding and polishing fluid. Detailed Embodiment

[0030] The present application will be further described in detail below with reference to the embodiments.

[0031] The following are the sources and specifications of some raw materials of the present application. The raw materials used in the preparation examples and embodiments of the present application can all be obtained commercially, including but not limited to the raw materials of the following models and manufacturers, and raw materials with the same performance can all be used: 1. Organosilicon-modified polyurethane emulsion: Evonik SILIKOPUR 8081; 2. Silicon dioxide: particle size 50-100nm; 3. Zinc ricinoleate: Huaxiang Kejie, light yellow transparent liquid, content 98%; 4. Diisostearyl malate: CAS No. 67763-18-2, content 99%; 5. Polyglyceryl-10 myristate: CAS No. 87390-32-7, content 99%; 6, 1,4-Butanediol dimethacrylate: CAS No. 2082-81-7, content 99%; 7, Methyl vinyl ether / maleic anhydride copolymer: CAS No. 9011-16-9, content 99%; 8, Glycerol / inulin lauryl carbamate: INUTEC SL1 from France; 9, Polyoxyethylene sorbitan esters: Tween 20, Tween 60 or Tween 80. Examples

[0032] Example 1 Example 1 discloses a preparation method of a highly stable grinding and polishing fluid, including the following steps: S1. Dissolve 0.2 kg of sodium citrate as a complexing agent in 1.72 kg of water, then add 1.5 kg of organosilicon-modified polyurethane emulsion, 1.5 kg of oil stabilizer (composed of zinc ricinoleate, diisostearyl malate and polyglycerol-10 myristate in a weight ratio of 1:1:1), 0.5 kg of dispersant (composed of polyethylene glycol 400 and methyl vinyl ether / maleic anhydride copolymer in a weight ratio of 1:1) and 0.58 kg of Tween 20 as an emulsifier, and raise the temperature for emulsification to 60 °C with an emulsification time of 2 h to obtain an emulsion; S2. Add 4 kg of silicon dioxide with a particle size of 50 nm to the emulsion, stir and disperse it, control the stirring rate at 1000 r / min, and stir for 30 min to obtain a highly stable grinding and polishing fluid.

[0033] Examples 2-3 The differences between Examples 2-3 and Example 1 are that the raw material dosages and preparation parameters are different. See Table 1 below for details.

[0034] Table 1 Parameter table of Examples 1-3 Example 4 The difference between Example 4 and Example 1 is that the oil stabilizer is composed of zinc ricinoleate, diisostearyl malate and polyglycerol-10 myristate in a weight ratio of 1:2:0.4, and the others are the same as Example 1.

[0035] Example 5 The difference between Example 5 and Example 1 is that the oil stabilizer is composed of zinc ricinoleate, diisostearyl malate and polyglycerol-10 myristate in a weight ratio of 1:3:0.8, and the others are the same as Example 1.

[0036] Example 6 Example 6 is different from Example 4 in that the dispersant consists of 1,4-butanediol dimethacrylate and methyl vinyl ether / maleic anhydride copolymer with a weight ratio of 1:1, and the others are the same as in Example 4.

[0037] Example 7 Example 7 is different from Example 4 in that the dispersant consists of 1,4-butanediol dimethacrylate and methyl vinyl ether / maleic anhydride copolymer with a weight ratio of 1:2, and the others are the same as in Example 4.

[0038] Example 8 Example 8 is different from Example 4 in that the emulsifier consists of glycerol / inulin lauryl carbamate and polyoxyethylene sorbitan ester (Tween 20) with a weight ratio of 1:2.5, and the others are the same as in Example 4.

[0039] Example 9 Example 9 is different from Example 4 in that the emulsifier consists of glycerol / inulin lauryl carbamate and polyoxyethylene sorbitan ester (Tween 20) with a weight ratio of 1:3.5, and the others are the same as in Example 4.

[0040] Comparative example Comparative example 1 Comparative example 1 is different from Example 1 in that diisostearyl malate is replaced with polyglyceryl-10 myristate in equal amount, and the others are the same as in Example 1.

[0041] Comparative example 2 Comparative example 2 is different from Example 1 in that polyglyceryl-10 myristate is replaced with zinc ricinoleate in equal amount, and the others are the same as in Example 1.

[0042] Comparative example 3 Comparative example 3 is different from Example 1 in that the silicone-modified polyurethane emulsion is replaced with an aqueous polyurethane emulsion, Anda Huatai AH-1730, and the others are the same as in Example 1.

[0043] Comparative example 4 Comparative example 4 is different from Example 6 in that the oil stabilizer is replaced with a dispersant in equal amount, and the others are the same as in Example 6.

[0044] Performance detection test The following is a performance test on the highly stable grinding and polishing fluids prepared in Examples 1-9 and Comparative examples 1-④. The 6063 series aluminum alloy mobile phone middle frame is used as the grinding test workpiece for performance testing: 1. Grinding and polishing performance test Fix the middle frame of the mobile phone on the fixing table of the five-axis polishing machine, control the rotation speed of the polishing wheel to be 1000 r / min, dilute the grinding and polishing liquid with water to 20 wt%, control the flow rate of the grinding liquid to be 350 ml / min, conduct a polishing test on the middle frame of the mobile phone, and the polishing time is 2.5 min. Use a gloss meter to test the gloss (60°, unit: GU), take one point for each side for testing, and take the average value. The gloss greater than 100 GU is qualified; use a microscope to observe the scratch, pitting and orange peel grades. The scratch grades are as follows: Grade A has no scratches, no pitting, and no orange peel; Grade B has 1-5 scratches, no obvious pitting, and no obvious orange peel; Grade C has 6-10 scratches, slight pitting, and slight orange peel; Grade D has more than 11 scratches, obvious pitting, and obvious orange peel. Record the test data.

[0045] 2. Detection of grinding and polishing stability: Fix the middle frame of the mobile phone on the fixing table of the five-axis polishing machine, control the rotation speed of the polishing wheel to be 1000 r / min, dilute the grinding and polishing liquid with water to 20 wt%, control the flow rate of the grinding liquid to be 350 ml / min, conduct a polishing test on the middle frame of the mobile phone, and the polishing time is 2.5 min. After circulating and polishing the grinding and polishing liquid 1000 times, test the gloss (60°, unit: GU) and scratch grade of the middle frame of the mobile phone, and record the test data.

[0046] The following are the performance test data of the high-stability grinding and polishing liquid of Examples 1-9 and Comparative Examples 1-4. For details, see Table 2 below.

[0047] Table 2 Data table of Examples 1-9 and Comparative Examples 1-4 “ / ” indicates not measured.

[0048] Combined with Examples 1-5 and Comparative Examples 1-2 and Table 2, it can be concluded that the grinding and polishing liquid prepared by using zinc ricinoleate, diisostearyl malate and polyglyceryl-10 myristate as oil stabilizers in this application has good polishing stability. Compared with Example 1, in Comparative Examples 1-2, the ratio and type of the oil stabilizer were changed. After the grinding and polishing liquid prepared was circulated and used 1000 times, the gloss was unqualified, and there were scratches, obvious pitting and obvious orange peel. This may be because the synergistic effect of the three was reduced, resulting in a decrease in the system stability of the grinding and polishing liquid, thereby reducing the continuous dispersion performance of silica in the system and reducing the polishing stability.

[0049] Combined with Example 4, Examples 6-9, and Comparative Example 4 and in conjunction with Table 2, it can be concluded that using 1,4-butanediol dimethacrylate and methyl vinyl ether / maleic anhydride copolymer of the present application as dispersants, glycerin / inulin lauryl carbamate and polyoxyethylene sorbitan esters as emulsifiers, has a good synergistic effect with the oiling agent, and the prepared grinding and polishing liquid has good polishing stability. Compared with Example 4, Examples 6-7 further optimized the types and ratios of the dispersants. After 1000 cycles of use, the prepared grinding and polishing liquid has no scratches, no pitting, and no orange peel. Compared with Example 4, Examples 8-9 further optimized the types and ratios of the emulsifiers. After 1000 cycles of use, the prepared grinding and polishing liquid has no scratches, no pitting, and no orange peel. Compared with Example 6, in Comparative Example 4, the oil stabilizer was replaced with a dispersant in equal amounts, and the prepared grinding and polishing liquid already had problems with unqualified gloss in the grinding and polishing test, and there were scratches, slight pitting, and slight orange peel. This further verifies the synergistic effect of the oil stabilizer and the dispersant of the present application.

[0050] Combined with Example 1 and Comparative Example 3 and in conjunction with Table 2, it can be concluded that using the organosilicon-modified polyurethane emulsion of the present application and compounding it with the system of the present application can improve the polishing stability of the grinding and polishing liquid. Compared with Comparative Example 1, in Comparative Example 3, the organosilicon-modified polyurethane emulsion was replaced with an aqueous polyurethane emulsion in equal amounts. After 1000 cycles of testing, the prepared grinding and polishing liquid had unqualified gloss, and there were scratches, slight pitting, and slight orange peel.

[0051] This specific embodiment is only an explanation of the present application, and it is not a limitation of the present application. Those skilled in the art can make modifications to this embodiment without creative contributions according to their needs after reading this specification, but as long as it is within the scope of the claims of the present application, it is protected by the patent law.

Claims

1. A high-stability grinding and polishing liquid, characterized in that: Prepared from raw materials with the following weight percentages: Silica 35 - 45% Silicone-modified polyurethane emulsion 15 - 25% Oil stabilizer 10 - 15% Dispersant 5 - 8% Emulsifier 3.8 - 5.8% Complexing agent 2 - 4% Preservative 0.1 - 0.3% The balance is water; The oil stabilizer is composed of zinc ricinoleate, diisostearyl malate, and polyglyceryl-10 myristate.

2. The high-stability grinding and polishing liquid according to claim 1, characterized in that: The oil stabilizer is composed of zinc ricinoleate, diisostearyl malate, and polyglyceryl-10 myristate in a weight ratio of 1:(2 - 3):(0.4 - 0.8).

3. A high-stability grinding and polishing liquid according to claim 1, characterized in that: The dispersant is composed of 1,4-butanediol dimethacrylate and methyl vinyl ether / maleic anhydride copolymer in a weight ratio of 1:(1 - 2).

4. A high-stability grinding and polishing liquid according to claim 1, characterized in that: The emulsifier is composed of glycerol / inulin lauryl carbamate and polyoxyethylene sorbitan ester in a weight ratio of 1:(2.5 - 3.5).

5. A highly stable grinding and polishing liquid according to claim 1, characterized in that: The particle size of the silica is 50 - 100 nm.

6. A highly stable grinding and polishing liquid according to claim 1, characterized in that: The complexing agent is any one or combination of sodium citrate, disodium ethylenediaminetetraacetate, and sodium gluconate.

7. A highly stable grinding and polishing liquid according to claim 1, characterized in that: The preservative is methylisothiazolinone and / or 1,2-benzisothiazolin-3-one.

8. A method for preparing a highly stable grinding and polishing liquid according to any one of claims 1-7, characterized in that: Including the following steps: S1. Dissolve the complexing agent in water, then add the silicone-modified polyurethane emulsion, oil stabilizer, dispersant, and emulsifier and heat up for emulsification to obtain an emulsion. S2. Add the silica to the emulsion and stir for dispersion to obtain a high-stability grinding and polishing fluid.

9. The preparation method of a highly stable grinding and polishing liquid according to claim 8, characterized in that: The heating temperature in step S1 is 60 - 80 °C, and the time is 1 - 2 h.

10. The preparation method of a high-stability grinding and polishing liquid according to claim 8, characterized in that: The stirring rate in step S2 is 800 - 1200 r / min.

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