A water-based silicon-based wall paint, a preparation method and application thereof

Abstract

The application provides a water-based silicon-based wall paint, a preparation method and application thereof, and the water-based silicon-based wall paint comprises the following components in percentage by mass: inorganic hybrid emulsion 20-30%, potassium silicate 3-5%, titanium white powder 20-25%, diatomite 3-5%, heavy calcium powder special for inorganic paint 3-5%, cellulose 0.2-0.5%, dispersing agent 0.8-1.5%, wetting agent 0.1-0.3%, defoaming agent 0.2-0.4%, thickening agent 0.5-1.5%, hydrophobic aid 0.5-1% and water 25-50%. The water-based silicon-based wall paint provided in the application has good stability, low SVOC, VOC and biocide content, excellent paint film scrubbing resistance, can pass the A2 level combustion performance test, has good flame-retardant effect, passes the 0 level mildew resistance test, and the stain resistance test is greater than or equal to 60 minutes.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of coatings, and particularly relates to a water-based silicon-based wall paint, a preparation method and application thereof. BACKGROUND

[0002] The coatings usually contain VOC, heavy metals, APEO, formaldehyde, bactericides, mildewproof agents (isothiazolinone, IPBC, ZPT) and other substances harmful to human body and environment. The most common consensus is that VOC refers to chemical substances with a boiling point equal to or lower than 250 DEG C, so those substances with a boiling point higher than 250 DEG C are not included in the category of VOC. In order to evade the limitation of VOC content, coating enterprises will choose to add some high-boiling solvents, namely SVOC, so that many so-called "zero VOC" products appear on the market. In fact, such products are more harmful. These SVOC have higher boiling points, slower evaporation, lower saturated vapor pressure, are more stable in the environment and are not easy to degrade, can exist in indoor environment for a longer time than ordinary VOC, and are more harmful to human body.

[0003] In addition, bactericides are also essential additives in coatings. The ability of in-can corrosion prevention of coatings and mildew and antibacterial resistance of dry film of coatings is realized by adding bactericides and mildewproof agents. We collectively refer to them as biological killing agents. However, bactericides have irreversible damage to human body, aquatic organisms and environment.

[0004] On January 10, 2022, Shanghai Coatings and Dyes Industry Association released the group standard T / SHCDA000003-2022 "Low Semi-Volatile Organic Compound Green Water-Based Interior Wall Coatings", which has a clear limitation on SVOC of building interior wall coatings. The product of superior quality is ≤30 g / L, isothiazolinone (CMIT, MIT, BIT), and IPBC, ZPT, etc. have different index limitations; GB / T35602-2017 "Green Product Evaluation Coatings" standard also has a limitation on the content of biological killing agents.

[0005] At present, with the upgrading of consumption, the public's demand for environmentally friendly and healthy living environment is getting higher and higher, especially in the process of decoration, more and more attention is paid to the environmental protection of the materials used, and products that can meet higher and more stringent environmental protection standards are needed.

[0006] Therefore, it is necessary to develop a coating with low SVOC, VOC and biological killing agent content, as well as mildew resistance, stain resistance and fire resistance. SUMMARY

[0007] In view of the deficiencies of the prior art, the present application aims to provide a water-based silicon-based wall paint, a preparation method and application thereof, which has good stability, low SVOC, VOC and biocide content, excellent washability of the paint film, can pass the A2 level combustion performance test, has good flame retardant effect, passes the 0 level mildew resistance test, and has a stain resistance test of greater than or equal to 60 points.

[0008] To achieve this purpose, the present application adopts the following technical solutions:

[0009] In a first aspect, the present application provides a water-based silicon-based wall paint, which comprises the following components in terms of mass percentage: inorganic hybrid emulsion 20-30% (for example, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28% or 29%, etc.), potassium silicate 3-5% (for example, 3.2%, 3.4%, 3.6%, 3.8%, 4.0%, 4.2%, 4.4%, 4.6% or 4.8%, etc.), titanium white powder 20-25% (for example, 20.5%, 21%, 21.5%, 22%, 22.5%, 23%, 23.5%, 24% or 24.5%, etc.), diatomite 3-5% (for example, 3.2%, 3.4%, 3.6%, 3.8%, 4.0%, 4.2%, 4.4%, 4.6% or 4.8%, etc.), heavy calcium powder special for inorganic paint 3-5% (for example, 3.2%, 3.4%, 3.6%, 3.8%, 4.0%, 4.2%, 4.4%, 4.6% or 4.8%, etc.), cellulose 0.2-0.5% (for example, 0.23%, 0.26%, 0.29%, 0.32%, 0.33%, 0.36%, 0.39%, 0.42%, 0.45% or 0.48%, etc.), dispersing agent 0.8-1.5% (for example, 0.9%, 1.0%, 1.1%, 1.2%, 1.3% or 1.4%, etc.), wetting agent 0.1-0.3% (for example, 0.12%, 0.14%, 0.16%, 0.18%, 0.20%, 0.22%, 0.24%, 0.26% or 0.28%, etc.), defoaming agent 0.2-0.4% (for example, 0.22%, 0.24%, 0.26%, 0.28%, 0.30%, 0.32%, 0.34%, 0.36% or 0.38%, etc.), thickening agent 0.5-1.5% (for example, 0.6%, 0.7%, 0.8%, 0.9%, 1.0%, 1.1%, 1.2%, 1.3% or 1.4%, etc.), hydrophobic aid 0.5-1% (0.55%, 0.6%, 0.65%, 0.7%, 0.75%, 0.8%, 0.85%, 0.9% or 0.95%, etc.), and water 25-50% (for example, 28%, 31%, 34%, 37%, 40%, 43%, 46% or 49%, etc.).

[0010] In this invention, the inorganic hybrid emulsion has low VOC and SVOC content and excellent resistance to microbial attack. Using potassium silicate as a binder eliminates the need for additional plasticizers (VOC film-forming aids) in the waterborne silicone-based wall paint formulation, resulting in a waterborne silicone-based wall paint with low VOC and SVOC content. The potassium silicate is inexpensive, self-cures at room temperature, exhibits less salt precipitation, good water resistance, high hardness, and better performance. It also significantly improves the scrub resistance of the paint film formed by the waterborne silicone-based wall paint. The hydrophobic additive further enhances the scrub resistance and stain resistance of the paint film. This invention, through the component design and selection of the content of each component in the water-based silicone wall paint, results in a water-based silicone wall paint with low organic content, good fire-retardant properties, good stability, low SVOC, VOC and biocide content, and excellent scrub resistance of the paint film. It can pass the A2-level flammability test, the 0-level mildew resistance test, and the stain resistance test score ≥60.

[0011] Preferably, the inorganic hybrid emulsion is an anionic, low-viscosity, odor-neutralizing polymer emulsion.

[0012] In this invention, low viscosity refers to a viscosity of 50 to 500 mPas, such as 100 mPas, 150 mPas, 200 mPas, 250 mPas, 300 mPas, 350 mPas, 400 mPas, or 450 mPas.

[0013] Preferably, the film-forming temperature of the anionic low-viscosity deodorizing polymer emulsion is ≤5℃, such as 0℃, 0.5℃, 1℃, 1.5℃, 2℃, 2.5℃, 3℃, 3.5℃, 4℃, or 4.5℃. Preferably, the pH of the anionic low-viscosity deodorizing polymer emulsion is 11-12, such as 11.1, 11.2, 11.3, 11.4, 11.5, 11.6, 11.7, 11.8, or 11.9.

[0014] In this invention, the anionic low-viscosity deodorizing polymer emulsion has an extremely high pH, ​​reaching 11-12, and possesses excellent resistance to microbial attack.

[0015] Preferably, the mass percentage of organic matter in the anionic low-viscosity deodorizing polymer emulsion is ≤5%, for example, 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, or 4.5%.

[0016] In this invention, the organic content is very low, resulting in a water-based silicone wall paint with low organic content and good fire-retardant properties.

[0017] Preferably, the anionic low-viscosity deodorizing polymer emulsion includes BASF ECO 7699.

[0018] Preferably, the potassium silicate includes potassium silicate specifically for high-solids-content inorganic silicate coatings.

[0019] In this invention, "high solids" refers to a solids content of 37-41%, such as 37.5%, 38%, 38.5%, 39%, 39.5%, 40%, or 40.5%.

[0020] Preferably, the potassium silicate for high-solids-content inorganic silicate coatings includes Aurun CR0SFECT K99.

[0021] Preferably, the titanium dioxide is rutile titanium dioxide.

[0022] Preferably, the titanium dioxide content in the rutile titanium dioxide is ≥95%, such as 95.5%, 96%, 96.5%, 97%, 97.5%, 98%, 98.5%, 99%, or 99.5%.

[0023] Preferably, the rutile titanium dioxide includes Lomon R996 and / or DuPont R902+.

[0024] Preferably, the median particle size of the diatomaceous earth is ≤10μm, such as 1μm, 2μm, 3μm, 4μm, 5μm, 6μm, 7μm, 8μm or 9μm.

[0025] Preferably, the diatomaceous earth comprises CELITE 499.

[0026] In this invention, the median particle size of the diatomaceous earth is ≤10μm. If the median particle size of the diatomaceous earth is too large, the diatomaceous earth will not be easily dispersed, and the surface smoothness of the paint film formed by the water-based silicone wall paint will be poor, resulting in a grainy feel.

[0027] Preferably, the inorganic coating-specific heavy calcium carbonate powder has a mesh size of 800-1250 mesh, such as 850 mesh, 900 mesh, 950 mesh, 1000 mesh, 1050 mesh, 1100 mesh, 1150 mesh or 1200 mesh, etc.

[0028] In this invention, the mesh size of the inorganic coating-specific heavy calcium carbonate powder is 800-1250 mesh. If the mesh size of the inorganic coating-specific heavy calcium carbonate powder is too large, the 60° side gloss of the paint film formed by the water-based silicone wall paint will be too high; if the mesh size of the inorganic coating-specific heavy calcium carbonate powder is too small, the feel of the paint film formed by the water-based silicone wall paint will be worse.

[0029] Preferably, the inorganic coating-specific heavy calcium carbonate powder includes Guangyuan 316.

[0030] Preferably, the cellulose comprises hydroxyethyl cellulose.

[0031] Preferably, the hydroxyethyl cellulose includes Ashland. 250HBR.

[0032] Preferably, the dispersant comprises an inorganic coating-specific dispersant.

[0033] Preferably, the inorganic coating-specific dispersant includes an acrylic polymer sodium salt dispersant.

[0034] Preferably, the acrylic polymer sodium salt dispersant comprises BASF Dispex AA 4140.

[0035] Preferably, the wetting agent comprises a nonionic wetting agent that does not contain APEO.

[0036] Preferably, the APEO-free nonionic wetting agent includes Aurun DA 202.

[0037] Preferably, the defoamer includes a polymer-composite mineral oil defoamer.

[0038] Preferably, the polymer-composite mineral oil defoamer includes BASF Foamstar st 2410AC.

[0039] Preferably, the thickener comprises an inorganic silicate thickener.

[0040] Preferably, the inorganic silicate thickener includes Hemings EW NA.

[0041] Preferably, the hydrophobic additive comprises an emulsion of aqueous silane and siloxane.

[0042] Preferably, the aqueous silane and siloxane emulsion comprises Wacker BS4004.

[0043] Preferably, the water-based silicone wall paint has a viscosity of 90-100 KU at 30°C, such as 91 KU, 92 KU, 93 KU, 94 KU, 95 KU, 96 KU, 97 KU, 98 KU, or 99 KU.

[0044] In a second aspect, the present invention provides a method for preparing a water-based silicone wall paint as described in the first aspect, the method comprising the following steps: mixing an inorganic hybrid emulsion, potassium silicate, titanium dioxide, diatomaceous earth, inorganic coating-specific heavy calcium carbonate powder, cellulose, dispersant, wetting agent, defoamer, thickener, hydrophobic additive and water to obtain the water-based silicone wall paint.

[0045] Preferably, the preparation method specifically includes the following steps:

[0046] (1) While stirring, slowly add dispersant, wetting agent, defoamer and cellulose to water in sequence, mix and obtain mixture A.

[0047] (2) Mix the mixture A obtained in step (1), titanium dioxide, diatomaceous earth and inorganic coating special heavy calcium carbonate powder to obtain mixture B.

[0048] (3) Mix the mixture B prepared in step (2), the inorganic hybrid emulsion and potassium silicate for the first time, add thickener and hydrophobic additive for the second time, and obtain the water-based silicone wall paint.

[0049] Preferably, the mixing speed in step (1) is 500-600 r / min (e.g., 510 r / min, 520 r / min, 530 r / min, 540 r / min, 550 r / min, 560 r / min, 570 r / min, 580 r / min or 590 r / min, etc.), and the mixing time is 3-5 min (e.g., 3.2 min, 3.4 min, 3.6 min, 3.8 min, 4.0 min, 4.2 min, 4.4 min, 4.6 min or 4.8 min, etc.).

[0050] Preferably, the mixing speed in step (2) is 1000-1200 r / min (e.g., 1030 r / min, 1060 r / min, 1090 r / min, 1120 r / min, 1150 r / min or 1180 r / min, etc.), and the mixing time is 20-30 min (e.g., 21 min, 22 min, 23 min, 24 min, 25 min, 26 min, 27 min, 28 min or 29 min, etc.).

[0051] Preferably, the fineness of the mixture B is ≤40μm, such as 5μm, 10μm, 15μm, 20μm, 25μm, 30μm or 35μm.

[0052] In this invention, the fineness of mixture B refers to the fineness of the particles in mixture B.

[0053] Preferably, the rotation speeds of the first and second mixing in step (3) are each independently 500-700 r / min, such as 530 r / min, 560 r / min, 590 r / min, 620 r / min, 650 r / min or 680 r / min, etc.

[0054] Preferably, the first mixing time in step (3) is 3-5 min, such as 3.2 min, 3.4 min, 3.6 min, 3.8 min, 4.0 min, 4.2 min, 4.4 min, 4.6 min or 4.8 min.

[0055] Preferably, the second mixing time in step (3) is 5-10 min, such as 5.5 min, 6.0 min, 6.5 min, 7.0 min, 7.5 min, 8.0 min, 8.5 min, 9.0 min or 9.5 min.

[0056] Thirdly, the present invention provides an application of the water-based silicone wall paint as described in the first aspect on a wall surface.

[0057] Compared with the prior art, the present invention has the following beneficial effects:

[0058] In this invention, the water-based silicone wall paint, through the design of its components and the selection of their contents, has low SVOC, VOC, and biocide content, and has passed the most stringent environmental certification recognized in the coating industry: the German Blue Angel certification; it can be stored at 50℃ for 14 days without stratification or sedimentation, has a hiding power >0.95, passes the freeze-thaw stability test, and the water-based silicone wall paint system is stable, meeting the superior grade standard in GB / T9756-2018 "Synthetic Resin Emulsion Interior Wall Coatings"; the paint film of the water-based silicone wall paint has excellent scrub resistance, passes the A2-level flammability test, passes the 0-level mildew resistance test, and has a stain resistance score ≥60. Detailed Implementation

[0059] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0060] The sources of some components in the examples and comparative examples are as follows:

[0061] Inorganic hybrid emulsion: Anionic low-viscosity, odor-neutralizing polymer emulsion, BASF ECO 7699;

[0062] Potassium silicate: High solids content inorganic silicate coating-specific potassium silicate, Aorun CR0SFECT K99;

[0063] Titanium dioxide: Rutile titanium dioxide, Longmang R996;

[0064] Titanium dioxide: Rutile titanium dioxide, DuPont R902+;

[0065] Diatomaceous earth: CELITE 499;

[0066] Inorganic coating special heavy calcium carbonate powder: Jiangxi Guangyuan Chemical 316;

[0067] Cellulose: Hydroxyethyl cellulose, Ashland 250HBR;

[0068] Dispersant: Sodium acrylate polymer dispersant, BASF Dispex AA 4140;

[0069] Wetting agent: APEO-free nonionic wetting agent, Aorun DA 202;

[0070] Defoamer: Polymer-based mineral oil defoamer, BASF Foamstar ST 2410AC;

[0071] Thickener: Inorganic silicate thickener, Hemings EW NA;

[0072] Hydrophobic additives: emulsions of aqueous silanes and siloxanes, Wacker BS4004;

[0073] Acrylic emulsion: Interior wall styrene-acrylic emulsion, Badifu 998A;

[0074] Ordinary heavy calcium carbonate powder: Jiangxi Guangyuan Chemical CC800.

[0075] Example 1

[0076] This embodiment provides a water-based silicone-based wall paint and its preparation method. The water-based silicone-based wall paint comprises the following components by mass percentage: 20% inorganic hybrid emulsion, 5% potassium silicate, 25% titanium dioxide (Longmang R996), 3% diatomaceous earth, 4% inorganic coating-specific heavy calcium carbonate powder, 0.5% cellulose, 0.8% dispersant, 0.2% wetting agent, 0.4% defoamer, 1% thickener, 0.5% hydrophobic additive, and 39.6% water.

[0077] The preparation method includes the following steps:

[0078] (1) Accurately weigh the raw material ratio of the above formula, add the accurately weighed water into the tank, turn on the disperser, and slowly add the dispersant, wetting agent, defoamer and cellulose into the water in sequence at a low speed of 550r / min. After the addition is completed, stir and mix for 4min to obtain mixture A.

[0079] (2) Add titanium dioxide, diatomaceous earth and inorganic coating special heavy calcium carbonate powder to the mixture A obtained in step (1), and gradually increase the rotation speed to 1100 r / min. Use a small amount of water to wash the cylinder wall and the powder remaining on the dispersion shaft. Mix and disperse for 25 min until the fineness is 35 μm to obtain mixture B.

[0080] (3) Reduce the rotation speed to 600 r / min, add inorganic hybrid emulsion and potassium silicate to the mixture B prepared in step (2) for the first mixing, stir for 4 min, add thickener and hydrophobic additive for the second mixing and continue stirring for 8 min, adjust the viscosity to 95 KU at 30℃ to obtain the water-based silicone wall paint.

[0081] Example 2

[0082] This embodiment provides a water-based silicone wall paint and its preparation method. The only difference between this embodiment and Embodiment 1 is that the mass percentage of potassium silicate is adjusted to 3% and the mass percentage of water is adjusted to 41.6%. The rest is the same as Embodiment 1.

[0083] Example 3

[0084] This embodiment provides a water-based silicone wall paint and its preparation method. The only difference between this embodiment and Embodiment 1 is that the mass percentage of the inorganic hybrid emulsion is adjusted to 30%, and the mass percentage of water is adjusted to 29.6%. The rest is the same as in Embodiment 1.

[0085] Example 4

[0086] This embodiment provides a water-based silicone wall paint and its preparation method. The only difference between this embodiment and Embodiment 1 is that the mass percentage of potassium silicate is adjusted to 3%, the mass percentage of hydrophobic additive is adjusted to 1%, and the mass percentage of water is adjusted to 41.1%. The rest is the same as in Embodiment 1.

[0087] Example 5

[0088] This embodiment provides a water-based silicone wall paint and its preparation method. The only difference between this embodiment and Embodiment 1 is that the mass percentage of potassium silicate is adjusted to 25%, the mass percentage of potassium silicate is adjusted to 4%, and the mass percentage of water is adjusted to 35.6%. The rest is the same as in Embodiment 1.

[0089] Example 6

[0090] This embodiment provides a water-based silicone-based wall paint and its preparation method. The water-based silicone-based wall paint comprises the following components by mass percentage: 20% inorganic hybrid emulsion, 5% potassium silicate, 20% titanium dioxide (DuPont R902+), 4% diatomaceous earth, 5% inorganic coating-specific heavy calcium carbonate powder, 0.2% cellulose, 1.5% dispersant, 0.1% wetting agent, 0.2% defoamer, 1.5% thickener, 0.5% hydrophobic additive, and 42% water.

[0091] The preparation method includes the following steps:

[0092] (1) Accurately weigh the raw material ratio of the above formula, add the accurately weighed water into the tank, turn on the disperser, and slowly add the dispersant, wetting agent, defoamer and cellulose to the water in sequence at a low speed of 500r / min. After the addition is completed, stir and mix for 3min to obtain mixture A.

[0093] (2) Add titanium dioxide, diatomaceous earth and inorganic coating special heavy calcium carbonate powder to the mixture A obtained in step (1), and gradually increase the rotation speed to 1000 r / min. Use a small amount of water to wash the cylinder wall and the powder remaining on the dispersion shaft. Mix and disperse for 30 min until the fineness is 40 μm to obtain mixture B.

[0094] (3) Reduce the rotation speed to 500 r / min, add inorganic hybrid emulsion and potassium silicate to the mixture B prepared in step (2) for the first mixing, stir for 3 min, add thickener and hydrophobic additive, mix for the second time and continue stirring for 5 min, adjust the viscosity to 100 KU at 30℃ to obtain the water-based silicone wall paint.

[0095] Example 7

[0096] This embodiment provides a water-based silicone-based wall paint and its preparation method. The water-based silicone-based wall paint comprises the following components by mass percentage: 20% inorganic hybrid emulsion, 5% potassium silicate, 23% titanium dioxide (Longmang R996), 5% diatomaceous earth, 3% inorganic coating-specific heavy calcium carbonate powder, 0.4% cellulose, 1% dispersant, 0.3% wetting agent, 0.3% defoamer, 0.5% thickener, 0.7% hydrophobic additive, and 40.8% water.

[0097] The preparation method includes the following steps:

[0098] (1) Accurately weigh the raw material ratio of the above formula, add the accurately weighed water into the tank, turn on the disperser, and slowly add the dispersant, wetting agent, defoamer and cellulose into the water in sequence at a low speed of 600r / min. After the addition is completed, stir and mix for 5min to obtain mixture A.

[0099] (2) Add titanium dioxide, diatomaceous earth and inorganic coating special heavy calcium carbonate powder to the mixture A obtained in step (1), and gradually increase the rotation speed to 1200 r / min. Use a small amount of water to wash the cylinder wall and the powder remaining on the dispersion shaft. Mix and disperse for 20 min until the fineness is 30 μm to obtain mixture B.

[0100] (3) Reduce the rotation speed to 700 r / min, add inorganic hybrid emulsion and potassium silicate to the mixture B prepared in step (2) for the first mixing, stir for 5 min, add thickener and hydrophobic additive, mix for the second time and continue stirring for 10 min, adjust the viscosity to 90 KU at 30℃ to obtain the water-based silicone wall paint.

[0101] Comparative Example 1

[0102] This comparative example provides a water-based wall paint and its preparation method. The only difference between this example and Example 1 is that the inorganic hybrid emulsion is replaced with the same mass of acrylic emulsion (Badfu 998A), while the other conditions are the same as in Example 1.

[0103] Comparative Example 2

[0104] This comparative example provides a water-based silicone wall paint and its preparation method. The only difference between this example and Example 1 is that potassium silicate is not added, the mass percentage of the inorganic hybrid emulsion is adjusted to 25%, and other conditions are the same as in Example 1.

[0105] Comparative Example 3

[0106] This comparative example provides a water-based silicone wall paint and its preparation method. The only difference between this example and Example 1 is that the inorganic coating-specific heavy calcium carbonate powder is replaced with the same mass of ordinary heavy calcium carbonate powder (Jiangxi Guangyuan Chemical CC800). All other conditions are the same as in Example 1.

[0107] Comparative Example 4

[0108] This comparative example provides a water-based silicone wall paint and its preparation method. The only difference between this example and Example 1 is that the mass percentage of the inorganic hybrid emulsion is adjusted to 15%, the mass percentage of water is adjusted to 49.6%, and the other conditions are the same as in Example 1.

[0109] Comparative Example 5

[0110] This comparative example provides a water-based silicone wall paint and its preparation method. The only difference between this example and Example 1 is that the mass percentage of the inorganic hybrid emulsion is adjusted to 35%, the mass percentage of water is adjusted to 24.6%, and the other conditions are the same as in Example 1.

[0111] Comparative Example 6

[0112] This comparative example provides a water-based silicone wall paint and its preparation method. The only difference between this example and Example 1 is that no hydrophobic additive is added, the water mass percentage is adjusted to 40.1%, and other conditions are the same as in Example 1.

[0113] Comparative Example 7

[0114] This comparative example provides a water-based silicone wall paint and its preparation method. The only difference between this example and Example 1 is that the mass percentage of potassium silicate is adjusted to 8% and the mass percentage of water is adjusted to 36.6%, while other conditions are the same as in Example 1.

[0115] Comparative Example 8

[0116] This comparative example provides a water-based silicone wall paint and its preparation method. The only difference between this example and Example 1 is that the mass percentage of potassium silicate is adjusted to 1%, the mass percentage of water is adjusted to 43.6%, and the other conditions are the same as in Example 1.

[0117] The following tests were conducted on the water-based silicone wall paint and water-based wall paint provided in the above embodiments and comparative examples:

[0118] The content of VOC, SVOC and harmful substances (total isothiazolinone, formaldehyde, soluble lead and plasticizer) was tested in accordance with GB / T 18582-2020 "Limits of Hazardous Substances in Wall Coatings for Buildings" and GB / T35602-2017 "Evaluation of Green Products Coatings". If the test results meet the limit requirements, it is recorded as OK; if the test results do not meet the limit requirements, it is recorded as exceeding the standard.

[0119] The following tests were conducted according to the superior grade standard of GB / T 9756-2018 "Synthetic Resin Emulsion Interior Wall Coatings": stability, workability, low-temperature cycling, low-temperature film formation, drying time, contrast ratio, hiding power, and scrub resistance. Weather resistance was tested according to GB / T 9755-2014 "Synthetic Resin Emulsion Exterior Wall Coatings," and stain resistance was tested according to GB / T 34676-2017 "Interior Wall Coatings for Children's Decorative Rooms." Test results meeting the standard requirements were marked as OK; test results not meeting the standard requirements were marked as Fail.

[0120] Anti-mildew tests were conducted in accordance with HG / T 3950-2007 "Antibacterial Coatings".

[0121] The combustion performance was tested in accordance with GB / T 8624-2012 "Classification of Combustion Performance of Building Materials and Products".

[0122] The test results are shown in Tables 1, 2 and 3.

[0123] Table 1

[0124]

[0125]

[0126] Table 2

[0127]

[0128]

[0129] In Table 2, “\” indicates that the test was not performed.

[0130] Table 3

[0131]

[0132] In Table 3, “\” indicates that the test was not performed.

[0133] As shown in Table 1, the water-based silicone wall paints provided in Examples 1-7 do not exhibit stratification or sedimentation after 14 days of storage at 50℃. They demonstrate good low-temperature cycling performance, pass freeze-thaw stability tests, and exhibit a stable product system. With a hiding power >0.95, the water-based silicone wall paints exhibit excellent washability. They meet the superior grade standard of GB / T 9756-2018 "Synthetic Resin Emulsion Interior Wall Coatings".

[0134] Meanwhile, the water-based silicone wall paints provided in Examples 1-7 have extremely low VOC, SVOC, and biocide content, and have passed the most stringent environmental certification recognized in the coatings industry: the German Blue Angel certification. Furthermore, because the raw materials of these water-based silicone wall paints are mainly inorganic, the paint film can achieve A2-level flammability, demonstrating good flame retardant and fireproof effects. In addition, these water-based silicone wall paints passed the 0-level mildew resistance and stain resistance test with a score of ≥60, and passed the 1-level stain resistance test.

[0135] Compared with Example 1, if the inorganic hybrid emulsion is replaced with the same mass of acrylic emulsion (Comparative Example 1), the contents of SVOC, total isothiazolinone, and plasticizer all exceed the standard. At the same time, the low-temperature cycling, low-temperature film formation, washability, and flame retardant properties all deteriorate.

[0136] Compared with Example 1, if potassium silicate is not added (Comparative Example 2), the washability and stain resistance of the water-based silicone wall paint film deteriorates. This is because silicates usually react with carbon dioxide in the air: 2M2O·nSiO2+CO2→M2O(2n-1)SiO2+M2CO3+SiO2. The reaction can generate polysilicates with higher modulus and larger molecular weight. If potassium silicate is not added, the final silica network skeleton gel structure is insufficient, resulting in a decrease in the overall performance of the water-based silicone wall paint film.

[0137] Compared with Example 1, if the inorganic coating-specific heavy calcium carbonate powder is replaced with the same mass of ordinary heavy calcium carbonate powder (Comparative Example 3), the water-based silicone wall paint gels in the container, and the stability of the product is problematic. This is because if the purity of ordinary heavy calcium carbonate powder is insufficient and it contains impurities, the Fe and Mg ions in the impurities will affect the stability of the system.

[0138] Compared with Example 1, if the mass percentage of the inorganic hybrid emulsion is too low (Comparative Example 4), the performance of low-temperature cycling, low-temperature film formation, scrub resistance, and stain resistance all deteriorate; if the mass percentage of the inorganic hybrid emulsion is too high (Comparative Example 5), the drying time and comparative ratio tests fail. Therefore, it can be seen that water-based silicone wall paint with a mass percentage of 20-30% of inorganic hybrid emulsion has better performance.

[0139] Compared with Example 1, if no hydrophobic additive is added (Comparative Example 6), the washability and stain resistance of the paint film formed by the water-based silicone wall paint are worse.

[0140] Compared to Example 1, if the mass percentage of potassium silicate is too high (Comparative Example 7), the water-based silicone wall paint exhibits a thickening and semi-gelling state in the container, resulting in product stability issues. If the mass percentage of potassium silicate is too low (Comparative Example 8), the washability and stain resistance of the water-based silicone wall paint film deteriorates. Potassium silicate typically reacts with carbon dioxide in the air to form polypotassium silicate. If the potassium silicate content is too low, the resulting silica network skeleton gel structure is insufficient, leading to a decrease in the overall performance of the water-based silicone wall paint film. If the potassium silicate content is too high, excessive polypotassium silicate is generated, resulting in a thickening and semi-gelling state. Therefore, water-based silicone wall paints with a potassium silicate mass percentage of 3-5% exhibit better performance.

[0141] The applicant declares that this invention illustrates a water-based silicone-based wall paint, 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, additions of auxiliary components, and selection of specific methods, etc., all fall within the protection and disclosure scope of this invention.

Claims

1. A water-based silicone-based wall paint, characterized in that, The components of the water-based silicone wall paint, by mass percentage, are: 20-30% inorganic hybrid emulsion, 3-5% potassium silicate, 20-25% titanium dioxide, 3-5% diatomaceous earth, 3-5% inorganic coating-specific heavy calcium carbonate powder, 0.2-0.5% cellulose, 0.8-1.5% dispersant, 0.1-0.3% wetting agent, 0.2-0.4% defoamer, 0.5-1.5% thickener, 0.5-1% hydrophobic additive, and 25-50% water; The inorganic hybrid emulsion is an anionic, low-viscosity, odor-neutralizing polymer emulsion. The anionic low-viscosity deodorizing polymer emulsion is BASF ECO 7699; The potassium silicate includes potassium silicate specifically for high-solids-content inorganic silicate coatings. The potassium silicate for high-solids inorganic silicate coatings is Aurun CR0SFECT K99. The inorganic coating-specific heavy calcium carbonate powder is Jiangxi Guangyuan Chemical 316; The dispersant includes an inorganic coating-specific dispersant; The inorganic coating-specific dispersant includes an acrylic polymer sodium salt dispersant.

2. The water-based silicone wall paint according to claim 1, characterized in that, The pH of the anionic low-viscosity deodorizing polymer emulsion is 11-12.

3. The water-based silicone-based wall paint according to claim 1, characterized in that, The mass percentage of organic matter in the anionic low-viscosity deodorizing polymer emulsion is ≤5%.

4. The water-based silicone wall paint according to claim 1, characterized in that, The film-forming temperature of the anionic low-viscosity deodorizing polymer emulsion is ≤5℃.

5. The water-based silicone wall paint according to claim 1, characterized in that, The titanium dioxide is rutile titanium dioxide.

6. The water-based silicone wall paint according to claim 5, characterized in that, The titanium dioxide content in the rutile titanium dioxide is ≥95%.

7. The water-based silicone-based wall paint according to claim 1, characterized in that, The median particle size of the diatomite is ≤10μm.

8. The water-based silicone wall paint according to claim 1, characterized in that, The mesh size of the inorganic coating-specific heavy calcium carbonate powder is 800-1250 mesh.

9. The water-based silicone wall paint according to claim 1, characterized in that, The cellulose includes hydroxyethyl cellulose.

10. The water-based silicone wall paint according to claim 1, characterized in that, The wetting agent includes a nonionic wetting agent that does not contain APEO.

11. The water-based silicone wall paint according to claim 1, characterized in that, The defoamer includes polymer-composite mineral oil defoamers.

12. The water-based silicone wall paint according to claim 1, characterized in that, The thickener includes inorganic silicate thickeners.

13. The water-based silicone wall paint according to claim 1, characterized in that, The hydrophobic additives include emulsions of aqueous silanes and siloxanes.

14. The water-based silicone wall paint according to claim 1, characterized in that, The viscosity of the water-based silicone wall paint at 30°C is 90-100 KU.

15. A method for preparing a water-based silicone-based wall paint as described in any one of claims 1-14, characterized in that, The preparation method includes the following steps: mixing inorganic hybrid emulsion, potassium silicate, titanium dioxide, diatomaceous earth, inorganic coating-specific heavy calcium carbonate powder, cellulose, dispersant, wetting agent, defoamer, thickener, hydrophobic additive and water to obtain the water-based silicone wall paint.

16. The preparation method according to claim 15, characterized in that, The preparation method specifically includes the following steps: (1) While stirring, slowly add dispersant, wetting agent, defoamer and cellulose to water in sequence, mix and obtain mixture A; (2) Mix the mixture A obtained in step (1), titanium dioxide, diatomaceous earth and inorganic coating special heavy calcium carbonate powder to obtain mixture B; (3) Mix the mixture B prepared in step (2), the inorganic hybrid emulsion and potassium silicate for the first time, add thickener and hydrophobic additive for the second time, and obtain the water-based silicone wall paint.

17. The preparation method according to claim 16, characterized in that, The mixing speed in step (1) is 500-600 r / min, and the mixing time is 3-5 min.

18. The preparation method according to claim 16, characterized in that, The mixing speed in step (2) is 1000-1200 r / min, and the mixing time is 20-30 min.

19. The preparation method according to claim 16, characterized in that, The fineness of the mixture B is ≤40 μm.

20. The preparation method according to claim 16, characterized in that, In step (3), the rotation speeds for the first and second mixing are each 500-700 r / min.

21. The preparation method according to claim 16, characterized in that, The first mixing time in step (3) is 3-5 minutes.

22. The preparation method according to claim 16, characterized in that, The second mixing time in step (3) is 5-10 min.

23. The application of a water-based silicone wall paint as described in any one of claims 1-14 on a wall surface.

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