An artistic paint with low release, non-sensitizing, stain resistant and clear texture and a preparation method thereof

Abstract

The present application relates to the field of paint, and more particularly to an artistic paint with low release, non-allergic, stain-resistant and clear texture and a preparation method thereof, which comprises the following raw materials in parts by weight: premixed solution A 36-54 parts, premixed solution B 18.7-24.85 parts, additives 0.15-3 parts, pigments 18-22 parts, and fillers 9-17 parts; the premixed solution A comprises emulsion A, emulsion B and silica sol; the volume ratio of emulsion A: emulsion B: silica sol is 6:2:1; the MFFT of the emulsion A is 5-10 DEG C, and the MFFT of the emulsion B is 0-5 DEG C. The paint solves the problems of the existing interior wall paint, such as insufficient environmental protection, high release amount of VOC, TVOC and SVOC, and poor low-temperature film-forming property of the product, and at the same time, the paint can easily remove common life stains such as watercolor pen, neutral pen, tea stain and ink.

Description

Technical Field

[0001] This invention relates to the field of coatings, and more specifically, to an artistic coating with low release, non-allergenic properties, stain resistance, and clear texture, as well as a method for its preparation. Background Technology

[0002] Currently, artistic coatings generally suffer from the following problems: ① Insufficient environmental friendliness: Traditional formulas rely on alcohol ester film-forming aids (such as dodecyl alcohol ester) and ethylene glycol antifreeze, resulting in high VOC, SVOC, and TVOC emissions; ② Poor low-temperature adaptability: When film-forming aids are lacking, the coating is prone to cracking and discontinuous film formation below 5℃. Furthermore, without antifreeze, emulsion demulsification and coarsening are likely to occur below 0℃, leading to product damage; ③ Conflicting performance: Coatings without film-forming aids typically have lower hardness, making it difficult to meet the stain resistance standards in the HGT 4756-2014 standard for stain-resistant latex paints for interior walls. High hardness requires the addition of film-forming aids, leading to VOC, SVOC, and TVOC emissions. In addition, there are requirements for watercolor pen resistance and texture performance. Summary of the Invention

[0003] The purpose of this invention is to provide an artistic coating with low release, non-allergenic properties, stain resistance, and clear texture, which solves the problems of insufficient environmental protection of existing interior wall coatings, high release of VOC, TVOC, and SVOC, and poor film-forming properties at low temperatures, while also enabling easy removal of common household stains such as watercolor pens, ballpoint pens, tea stains, and ink stains.

[0004] Another objective of this invention is to provide a method for preparing an artistic coating that has low release, is non-allergenic, stain-resistant, and has a clear texture. This method is simple and requires minimal equipment.

[0005] The technical problem solved by this invention is achieved by the following technical solution.

[0006] On one hand, embodiments of the present invention provide an artistic coating with low release, non-allergenic properties, stain resistance, and clear texture, comprising the following raw materials by weight: Premixed solution A 36-54 parts, premixed solution B 18.7-24.85 parts, additives 0.15-3 parts, pigments 18-22 parts, fillers 9-17 parts; The premixed solution A comprises emulsion A, emulsion B, and silica sol; the mass ratio of emulsion A: emulsion B: silica sol is 6:2:1. The MFFT of emulsion A is at 5-10°C, and the MFFT of emulsion B is at 0-5°C.

[0007] In some embodiments of the present invention, the premixed solution B comprises, by weight, 17.3-22.65 parts water, 0.6-1 parts bentonite, and 0.8-1.2 parts dispersant.

[0008] In some embodiments of the present invention, the pigment is rutile titanium dioxide; the pigment is rutile titanium dioxide prepared by chlorination and its inorganic coating treatment is alumina, silicon dioxide, or zirconium oxide.

[0009] The filler comprises, by weight, 4-8 parts glass flakes and 5-9 parts nano-SiO2-coated barite.

[0010] The nano-SiO2-coated modified barite is prepared by the following steps: Step S1: Activation of barite surface and construction of flexible interface. Disperse barite powder in anhydrous ethanol and stir at high speed (1000-1500 rpm) for 30 min. Slowly add pre-hydrolyzed silane coupling agent (dissolve the coupling agent in a small amount of ethanol and water and hydrolyze for 10 min), heat to 60-70℃, and react for 1-2 hours.

[0011] Objective: To graft an organosilane molecular layer onto the surface of barite. This molecular chain has a certain degree of flexibility, acting as a "flexible interface layer" that can effectively transfer stress and prevent the subsequently formed rigid SiO2 shell from peeling off when the coating is under stress.

[0012] Step S2: In-situ growth and coating of nano-SiO2. Maintaining the reaction temperature at 60℃, add deionized water and ammonia to the system and adjust the pH to 9-10 to form an alkaline catalytic environment. Mix tetraethyl orthosilicate (TEOS) and anhydrous ethanol in a 1:4 ratio and add the mixture dropwise to the reaction system at an extremely slow rate (controlling the dropping rate is crucial, such as 1-2 drops / second) through a constant pressure dropping funnel.

[0013] Key control point: Maintain high-speed shear dispersion during the dropwise addition process. TEOS hydrolyzes under alkaline conditions to generate silicic acid, which then condenses and nucleates on the surface of activated barite.

[0014] Differentiated Design: Conventional methods on the market typically involve adding TEOS all at once or rapid precipitation, which easily leads to the formation of lumpy agglomerates. This method uses a "starved state with slow drop-down" to control supersaturation, prompting SiO2 to grow a uniform, dense, and nano-rough mesoporous SiO2 shell with barite surface as the crystal nucleus.

[0015] Step S3: Aging, Filtration, and Low-Temperature Drying. After the addition of the additives, continue stirring for 2-4 hours to age the product, making the shell structure more compact. After the reaction, filter and wash with ethanol multiple times to remove byproducts. Finally, vacuum dry at 60-80℃, grind and disperse to obtain nano-SiO2-coated modified barite.

[0016] In some embodiments of the present invention, the additives include, by weight, 0.05-0.1 parts of defoamer and 0.1-0.2 parts of preservative and mildew inhibitor.

[0017] In some embodiments of the present invention, the defoamer is a mixture of polyether organosilicon mineral oil; The preservative and antifungal agent is at least one of isothiazolinones, formaldehyde-releasing agents, and benzimidazoles.

[0018] On the other hand, embodiments of the present invention provide a method for preparing an artistic coating with low release, non-allergenic properties, stain resistance, and clear texture, comprising the following steps: Step S1: Preparation of premixed solution A: First, add silica sol to emulsion A, then add emulsion B under high-speed stirring at 1300-1600 rpm, stir for 15-30 min, and then let it stand for 24 h to mature, thus obtaining premixed solution A; Step S2: Preparation of premixed solution B: First, add bentonite to water, add dispersant while stirring at high speed of 1300-1600 rpm, and stir for 15-30 min to obtain premixed solution B; Step S3: Add defoamer, pigment and filler to premixed solution B, and stir at high speed of 1300-1600 rpm for 15-30 min until the fineness is ≤60um; Step S4: Add premixed solution A and anti-corrosion and anti-mildew agent, and stir at 500-800 rpm for 5-10 minutes to obtain the artistic coating.

[0019] The coating provided in this embodiment of the invention uses a premixed solution A composed of two emulsions in synergy. Specifically, emulsion A with MFFT at 5-10°C is selected as a high-hardness matrix, and emulsion B with MFFT at 0-5°C is used as a flexible matrix. In the presence of silica sol, a synergistic effect can be formed. Through the chemical bonding of silicon-oxygen bonds with organic polymers, a three-dimensional network structure can be spontaneously formed, which enhances the density of the coating film, further reduces the need for film-forming aids and improves the strength of the paint film.

[0020] The use of nano-SiO2 to coat barite enhances its mechanical strength, while glass flakes, as the sheet material, act as stress dispersers and crack inhibitors, forming a physical barrier similar to brick and mortar. The synergistic effect of these two materials further improves the interfacial adhesion of the coating. Furthermore, in the case of silica sol, a synergistic effect is formed with the nano-SiO2-coated barite, further increasing the hardness of the paint film. Chemical bonding nodes: During synthesis, the SiO2 shell on the barite surface contains a large number of active silanol groups. During coating curing, these silanol groups can undergo dehydration condensation reactions with the "silica sol" (premixed solution A) mentioned in the patent, forming strong Si-O-Si chemical bonds. Physical interlocking network: This method controls the generated SiO2 shell to have nanoscale roughness and a mesoporous structure. This structure can not only chemically bond but also physically entangle the organic emulsion particles to the filler surface. When the emulsion forms a film, the filler is no longer an isolated filler but becomes a "rigid node" in the three-dimensional network structure of the paint film, thereby significantly improving the hardness of the paint film.

[0021] To achieve excellent watercolor-resistant performance, extreme hydrophobicity or extremely low surface tension is required. Therefore, it is necessary to remove or replace hydrophilic materials in existing formulations, such as cellulose, dispersants, wetting agents, alkali-soluble thickeners, and pH adjusters. These materials play a crucial role in texture setting and powder stability. Therefore, this invention uses bentonite as a key texture-setting material. Bentonite exhibits different thixotropic properties compared to different dispersants and wetting agents. Under the action of macromolecular dispersants, fine powder dispersion can be achieved without the need for wetting agents. On the other hand, when combined with bentonite, it enhances the thixotropic properties of bentonite, eliminating the need for additional cellulose, alkali-soluble thickeners, and pH adjusters. This significantly reduces the hydrophilicity of the paint film. Furthermore, due to the reduction of surfactants and cellulose, the use of defoamers containing high levels of VOCs and TVOCs can be significantly reduced.

[0022] Compared with the prior art, the embodiments of the present invention have at least the following advantages or beneficial effects: The present invention provides a low-release, non-allergenic coating that solves the problems of insufficient environmental protection of existing interior wall coatings, such as high release of VOC, TVOC, and SVOC and poor film-forming properties at low temperatures, while also enabling easy removal of common household stains such as watercolor pens, ballpoint pens, tea stains, and ink stains.

[0023] Environmental breakthrough: VOC content ≤2g / L (GB 18582-2020); extremely low total volatile organic compound (TVOC) release, TVOC content <0.5mg / m³ within 24 hours, <0.2mg / m³ within 48 hours, and <0.075mg / m³ within 336 hours (according to ASP:04-01 Paint Indoor Decorative wall standard), meeting the certification requirements for children's room paint and for products suitable for breathing allergies; Low-temperature self-crosslinking: It can still form a 1000um film at 2℃, so it can still make a product with good film-forming properties and a lambskin texture effect at low temperatures; while the traditional system requires above 5℃ and the thickness is only 200um, so it is more difficult to make textured products with thickness requirements.

[0024] Performance balance: Under low temperature and thick coating conditions, the hardness can meet the stain resistance standard (HGT 4756-2014), and the paint film's resistance to watercolor pen marks can be easily wiped off within 48 hours, while traditional high-end latex paint can be wiped off within 4 hours. To achieve the same effect as paint that can still be wiped off within 48 hours, an additional layer of clear varnish is required. In addition, the coating of this invention also has a clear texture effect. Attached Figure Description

[0025] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a photograph of the actual product after the coating of Embodiment 1 of the present invention has been cured. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0028] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to specific embodiments.

[0029] The features and performance of the present invention will be further described in detail below with reference to embodiments. Example 1: An artistic coating with low release, non-allergenic properties, stain resistance, and clear texture, and its preparation method are as follows: Step S1: Preparation of premixed solution A: First, add 5 parts of silica sol (Cima V-33) to 30 parts of emulsion A (Dow SF-508), then add 10 parts of emulsion B (Dow SF-708) while stirring at high speed of 1300-1600 rpm. After stirring for 15-30 min, premixed solution A is obtained, and then allowed to stand for 24 h for aging. Step S2: Preparation of premixed solution B: First, add 0.8 parts of bentonite (grid 442) to 19.975 parts of water and disperse by high-speed stirring at 1300-1600 rpm. Then, add 1 part of dispersant (BYK-183) and stir for 15-30 minutes to obtain premixed solution B. Step S3: Add 0.075 parts of defoamer (polyether siloxane, manufacturer: Evonik's TEGO® Foamex 32) and 20 parts of titanium dioxide (pigment, Longmang titanium dioxide BLR-895), 6 parts of glass flakes, and 7 parts of nano-SiO2-coated barite to premixed solution B. Disperse the mixture at high speed (1300-1600 rpm) for 15-30 minutes until the fineness is ≤60 μm. Step S4: Add the cured premixed solution A and 0.15 parts of preservative and mildew inhibitor (Dow, ROCIMA™ 562) and stir at 500-800 rpm for 5-10 minutes to obtain the finished product. Apply this coating to the substrate. The actual product after curing is shown in the image below. Figure 1 As shown.

[0030] The nano-SiO2-coated barite used in this embodiment was prepared by the following steps: Step 1: Activation of barite surface and construction of flexible interface. Disperse barite powder in anhydrous ethanol and stir at high speed (1000-1500 rpm) for 30 min. Slowly add pre-hydrolyzed silane coupling agent (dissolve the coupling agent in a small amount of ethanol and water and hydrolyze for 10 min), heat to 60-70℃, and react for 1-2 hours.

[0031] Step 2: In-situ growth and coating of nano-SiO2. Maintaining the reaction temperature at 60℃, add deionized water and ammonia to the system, adjusting the pH to 9-10 to create an alkaline catalytic environment. Mix tetraethyl orthosilicate (TEOS) and anhydrous ethanol in a 1:4 ratio, and add the mixture dropwise to the reaction system at a very slow rate (1-2 drops / second) using a constant-pressure dropping funnel.

[0032] Step 3: Aging, Filtration and Low-Temperature Drying After the addition is complete, continue stirring for 2-4 hours to allow for aging and further densification of the shell structure. After the reaction is complete, filter and wash repeatedly with ethanol to remove byproducts. Finally, vacuum dry at 60-80℃, grind and disperse to obtain nano-SiO2-coated modified barite.

[0033] Example 2: An artistic coating with low release, non-allergenic properties, stain resistance, and clear texture, and its preparation method are as follows: Step S1: Preparation of premixed solution A: First, add 4 parts of silica sol to 24 parts of emulsion A, then add 8 parts of emulsion B while stirring and dispersing at high speed of 1300-1600 rpm. After stirring for 15-30 min, premixed solution A is obtained, and then allowed to stand for 24 h for aging. Step S2: Preparation of premixed solution B: First, add 1 part bentonite to 22.65 parts water and disperse at high speed (1300-1600 rpm). Then, add 1.2 parts dispersant and stir for 15-30 minutes to obtain premixed solution B. Step S3: Add 0.05 parts of defoamer, 22 parts of titanium dioxide, 8 parts of glass flakes, and 9 parts of nano-SiO2-coated barite to premixed solution B. Disperse the mixture at high speed of 1300-1600 rpm for 15-30 minutes until the fineness is ≤60 μm. Step S4: Add the matured premixed solution A and 0.1 parts of preservative and mildew inhibitor, and stir at 500-800 rpm for 5-10 minutes to obtain the finished product.

[0034] The raw materials used in this embodiment are the same as those in Example 1.

[0035] Example 3: An artistic coating with low release, non-allergenic properties, stain resistance, and clear texture, and its preparation method are as follows: Step S1: Preparation of premixed solution A: First, add 12 parts of silica sol to 36 parts of emulsion A, then add 6 parts of emulsion B while stirring and dispersing at high speed of 1300-1600 rpm. After stirring for 15-30 min, premixed solution A is obtained, and then allowed to stand for 24 h for aging. Step S2: Preparation of premixed solution B: First, add 0.6 parts of bentonite to 17.3 parts of water and disperse at high speed (1300-1600 rpm). Then, add 0.8 parts of dispersant and stir for 15-30 minutes to obtain premixed solution B. Step S3: Add 0.1 parts of defoamer, 18 parts of titanium dioxide, 5 parts of glass flakes, and 5 parts of nano-SiO2-coated barite to premixed solution B. Disperse the mixture at high speed (1300-1600 rpm) for 15-30 minutes until the fineness is ≤60 μm. Step S4: Add the matured premixed solution A and 0.2 parts of preservative and mildew inhibitor, and stir at 500-800 rpm for 5-10 minutes to obtain the finished product.

[0036] The raw materials used in this embodiment are the same as those in Example 1.

[0037] Comparative Example 1: Comparative Example 1 is based on Example 1, except that the premixed solution A in step S1 is not aged and is used directly.

[0038] Comparative Example 2: Comparative Example 2 is based on Example 1, but the emulsion B and silica sol in step S1 are replaced with emulsion A, that is, an equal amount of emulsion A is used to replace the premixed solution A in Example 1.

[0039] Comparative Example 3: Comparative Example 3 is based on Example 1, but emulsion A and silica sol in step S1 are replaced with emulsion B, that is, an equal amount of emulsion B is used to replace the premixed solution A in Example 1.

[0040] Comparative Example 4: Comparative Example 4 is based on Example 1, but emulsions A and B in step S1 are replaced with silica sol, that is, an equal amount of silica sol is used to replace the premixed solution A in Example 1.

[0041] Comparative Example 5: Comparative Example 5 is based on Example 1, except that the dispersant in step S2 is replaced with the small molecule dispersant SN-5040.

[0042] Comparative Example 6: Comparative Example 6 is based on Example 1, except that the glass flakes and nano-SiO2-coated barite in step S3 are replaced with an equal amount of heavy calcium carbonate powder.

[0043] Based on the coatings of the above embodiments and comparative examples, the following tests were conducted, and the results are shown in Table 1.

[0044] Viscosity: Measured at (23±2)℃ using a Stormer rotational viscometer.

[0045] Heat storage viscosity: Pour 300g of paint sample into a plastic cup and place it in an oven at 50℃ for 7 days. After curing, cool it to room temperature and measure it at (23±2)℃ using a Stormer rotational viscometer.

[0046] Fineness: Observed by scraping with a 100um fineness plate.

[0047] Low-temperature thick coating film formation: The paint sample and experimental equipment were placed in a constant temperature and humidity chamber at 2℃ for 2 hours in advance. Then, a 1000um wet film preparation device was used to make a film on the putty board within 30 seconds. The film formation was observed after 24 hours.

[0048] Stain resistance score: Tested according to HGT4756-2014.

[0049] Watercolor Resistance Test: A 200μm intermittent wet film was prepared on a PVC plastic sheet and cured for 7 days before testing. Chenguang brand water-based watercolor pens were applied to the film, and then the surface was wiped at different time intervals until it could no longer be wiped clean. The longest time interval is considered the product's watercolor resistance test duration.

[0050] Table 1

[0051] Table 1 shows that, compared with Comparative Example 1, the paint sample prepared in Example 1 has a higher stain resistance score and longer resistance to watercolor paints due to the curing process. This is because after curing, emulsions A and B undergo a room-temperature cross-linking reaction in the presence of silica sol, forming a modified emulsion complex. Hard emulsion A links soft emulsion B through silicon-oxygen bonds, forming an emulsion core with high hardness and a soft outer core, which can reduce the film-forming temperature while improving the density of the emulsion.

[0052] A comparison of Example 1 and Comparative Examples 2-4 revealed that using hard emulsion A alone resulted in low-temperature thick coating cracking, while using soft emulsion B alone resulted in insufficient film hardness, leading to film scuffing. Using pure silica sol alone resulted in high brittleness, low-temperature thick coating cracking, and insufficient powder coating, leading to film scuffing. Furthermore, without emulsion coating, pure silica sol would cause excessive reaction with the powder in the system, forming a gel, resulting in a gelled state in the final paint sample.

[0053] A comparison of Example 1 and Comparative Example 5 revealed that after the dispersant was changed, although the fineness could still reach 60, the viscosity rapidly reached its upper limit after heat storage, resulting in a gel state. This is because the dispersing ability of small molecule dispersants is limited, and they need to be used in conjunction with wetting agents and other surfactants. Using other surfactants further introduces VOCs, TVOCs, and SVOCs.

[0054] A comparison of Example 1 and Comparative Example 6 revealed that after the powder was replaced with heavy calcium carbonate, the stress was too great, which led to the cracking of the paint film when thickly coated at low temperature. Furthermore, due to the lack of the sheet-like structure to block the flow, the watercolor pen had higher penetration into the paint film, poor stain resistance, and reduced hardness of the paint film.

[0055] The embodiments described above are some, but not all, embodiments of the present invention. The detailed description of the embodiments of the present invention is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

Claims

1. An artistic coating characterized by low release, non-allergenicity, stain resistance, and clear texture, wherein... By weight, it includes the following ingredients: Premixed solution A 36-54 parts, premixed solution B 18.7-24.85 parts, additives 0.15-3 parts, pigments 18-22 parts, fillers 9-17 parts; The premixed solution A includes emulsion A, emulsion B, and silica sol; the mass ratio of emulsion A: emulsion B: silica sol is 6:2:1; The MFFT of emulsion A is at 5-10°C, and the MFFT of emulsion B is at 0-5°C.

2. The artistic coating with low release, non-allergenic properties, stain resistance, and clear texture as described in claim 1, characterized in that: The premixed solution B comprises, by weight, 17.3-22.65 parts water, 0.6-1 parts bentonite, and 0.8-1.2 parts dispersant.

3. The artistic coating with low release, non-allergenic properties, stain resistance, and clear texture as described in claim 2, is characterized in that... The pigment is rutile titanium dioxide; The filler comprises, by weight, 4-8 parts glass flakes and 5-9 parts nano-SiO2-coated barite.

4. The artistic coating with low release, non-allergenic properties, stain resistance, and clear texture as described in claim 3, characterized in that: The nano-SiO2-coated modified barite is prepared by the following steps: Step 1: Disperse barite powder in anhydrous ethanol, stir at 1000-1500 rpm for 30 min, add hydrolyzed silane coupling agent dropwise, heat to 60-70℃, and react for 1-2 hours. Step 2: Maintain the reaction temperature at 60℃, add deionized water and ammonia to the system, adjust the pH to 9-10, mix tetraethyl orthosilicate (TEOS) and anhydrous ethanol in a 1:4 ratio, and add them dropwise to the reaction system through a constant pressure dropping funnel; Step 3: After the addition is complete, continue stirring for 2-4 hours to age the product. After the reaction is complete, filter the product, wash it several times with ethanol, dry it under vacuum at 60-80℃, grind and break it up to obtain nano-SiO2 coated and modified barite.

5. The artistic coating with low release, non-allergenic properties, stain resistance, and clear texture as described in claim 3, characterized in that: The additives, by weight, include: 0.05-0.1 parts of defoamer and 0.1-0.2 parts of preservative and mildew inhibitor.

6. The artistic coating with low release, non-allergenic properties, stain resistance, and clear texture according to claim 4, characterized in that, The defoamer is a mixture of polyether organosilicon mineral oil; The preservative and antifungal agent is at least one of isothiazolinones, formaldehyde-releasing agents, and benzimidazoles.

7. A method for preparing an artistic coating with low release, non-allergenic properties, stain resistance, and clear texture as described in any one of claims 1-6, characterized in that, Includes the following steps: Step S1: Preparation of premixed solution A: First, add silica sol to emulsion A, then add emulsion B under high-speed stirring at 1300-1600 rpm, stir for 15-30 min, and then let it stand for 24 h to mature, thus obtaining premixed solution A; Step S2: Preparation of premixed solution B: First, add bentonite to water, add dispersant while stirring at high speed of 1300-1600 rpm, and stir for 15-30 min to obtain premixed solution B; Step S3: Add defoamer, pigment and filler to premixed solution B, and stir at high speed of 1300-1600 rpm for 15-30 min until the fineness is ≤60um; Step S4: Add premixed solution A and anti-corrosion and anti-mildew agent, and stir at 500-800 rpm for 5-10 minutes to obtain the artistic coating.

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