Water-based flexible smooth matte coating and preparation method thereof

Abstract

The invention relates to the technical field of coatings, in particular to a water-based flexible smooth matte coating and a preparation method thereof.The preparation method comprises the following steps that 1, metallic soap and a filler type delustering agent are sieved respectively, and powder with the target particle size is screened out; step 2, adding deionized water, a water-based acrylic emulsion, a polyethylene wax emulsion, a silane coupling agent, metallic soap, a filler type delustering agent, a softening agent and acrylate copolymer crosslinked microspheres into a stirring kettle, and uniformly stirring to obtain a uniform system; and 3, adjusting the pH value of the system, adding the nano silicon dioxide solution and the flatting agent, and uniformly stirring to obtain a finished product. The matt coating prepared by the invention has the effects of soft and smooth hand feeling and matt property while keeping the original strength of the glass fabric.

Description

Technical Field

[0001] This invention relates to the field of coating technology, specifically to a water-based flexible smooth matte coating and its preparation method. Background Technology

[0002] With social development and increased safety awareness, the demand for fire-resistant materials in various public places and transportation vehicles is rising. Fiberglass cloth, with its excellent fire resistance and certain sound insulation properties, is widely used in places such as KTVs, theaters, and transportation hubs. However, because fiberglass cloth itself can irritate the skin, and modern interior decoration generally pursues a matte finish, surface coating treatment is necessary for fiberglass cloth.

[0003] The current mainstream matting process uses synthetic silica microparticles with a particle size of 4-15 μm. However, this material has significant technical drawbacks in practical applications: First, its particle size is similar to that of glass fibers (5-20 μm), inevitably causing frictional damage during processing. Second, the irregular silica particles, with a Mohs hardness of 7, have sharp edges that can scratch the brittle glass fibers (Mohs hardness 5-6) during impregnation. Third, the internal stress generated by the difference in thermal expansion coefficients after coating curing further exacerbates fiber damage. Experimental data from the literature shows that using a single silica matting agent is ineffective: the scraping process causes a 30-50% strength loss in the fiberglass cloth, while the padding process causes a 40-70% strength reduction. Furthermore, the finished product suffers from stiffness and a rough surface, severely impacting the user experience and decorative effect. These defects make traditional matting processes unable to meet the dual requirements of modern decorative materials for both performance and aesthetics.

[0004] Based on the above-mentioned background problems, this invention proposes a water-based flexible smooth matte coating for fiberglass cloth and its preparation method, which achieves a soft, smooth and matte effect while retaining the original strength of the fiberglass cloth. Summary of the Invention

[0005] The purpose of this invention is to provide a water-based flexible smooth matte coating and its preparation method to solve the problems raised in the prior art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: Step 1: Sift the metallic soap and filler-type matting agent separately and set aside; Step 2: Add some deionized water to a stirred tank at 20~60℃. At a speed of 200~400rpm, add water-based acrylic emulsion, polyethylene wax emulsion and silane coupling agent in sequence. After stirring continuously for 15~30min, add pigments and fillers, metallic soap and filler-type matting agent. Increase the speed to 800~1200rpm and stir for 10~20min. Add softener and the remaining deionized water. Adjust the speed to 400~800rpm and stir for 5~20min to form a homogeneous system. Step 3: Adjust the pH of the system to 7-8.5, add nano silica solution and leveling agent in sequence, stir at 400-800 rpm for 10-20 min to obtain water-based flexible smooth matte coating.

[0007] Furthermore, the water-based flexible smooth matte coating comprises, by weight percentage, 15%~25% water-based acrylic resin emulsion, 2%~8% polyethylene wax emulsion, 5%~10% nano silica solution, 0.5%~3% metal soap, 0.5%~3% filler-type matting agent, 2%~10% pigments and fillers, 0.5%~1.5% silane coupling agent, 0.5%~1% softener, 0.1%~0.5% leveling agent, and the balance being deionized water.

[0008] Furthermore, the aqueous acrylic emulsion is a styrene-modified acrylic emulsion with a solid content of 40%~50%; the polyethylene wax emulsion has a solid content of 30%~50%; and the nano silica solution has a pH of 6~8, a solid content of 25%~40%, and a particle size of 5~50nm.

[0009] Furthermore, the metal soap is one or more of zinc stearate, calcium stearate, magnesium stearate, and aluminum stearate, with a particle size of 3-5 μm; the filler-type matting agent is one or more of talc, kaolin, and diatomaceous earth, with a particle size of 3-5 μm; the pigment / filler is an aqueous black paste; the silane coupling agent is one or more of aminosilane coupling agent, epoxysilane coupling agent, and vinylsilane coupling agent; the softener is nonionic phenyl silicone oil with a pH value of 6-7; and the leveling agent is an organosilicon-modified acrylic leveling agent.

[0010] Furthermore, the polyethylene wax undergoes modification treatment, the specific steps of which are as follows: Polyethylene wax, maleic anhydride, and acetone were mixed in a mass ratio of 10:1:10, heated to 50-55°C, stirred for 10-15 minutes, then heated to 80-85°C and stirred continuously until the acetone was completely evaporated. Nitrogen gas was then introduced, and the temperature was further increased to 110-115°C. Benzoyl peroxide and xylene were then added sequentially, and the temperature was increased to 138-142°C. The reaction was carried out for 3-3.5 hours to obtain a crude product. The crude product was mixed with xylene, heated in an oil bath, and refluxed for 1-1.5 hours. While still hot, the solution was poured into a beaker, and acetone was added to precipitate the precipitate. The precipitate was repeatedly filtered, washed, and dried with acetone to obtain modified polyethylene wax.

[0011] Furthermore, the nano-silica undergoes modification treatment, specifically through the following steps: Nano-silica was mixed with polypropylene glycol and vacuum dehydrated at 105-110℃ for 2-2.5h. After cooling to 20-25℃, isophorone diisocyanate, tripropylene glycol diacrylate, and dibutyltin dilaurate were added. The mixture was reacted at 80-85℃ for 3-3.5h. The reaction system was then cooled to 30-35℃, and hydroxyethyl methacrylate, tripropylene glycol diacrylate, p-hydroxyanisole, and dibutyltin dilaurate were added. The mixture was then heated to 80-85℃. After the reaction was completed, modified nano-silica was obtained.

[0012] Furthermore, the nano-silica is mixed with polypropylene glycol at a mass ratio of 0.7:49.3, isophorone diisocyanate and tripropylene glycol diacrylate are mixed at a mass ratio of 2:3, and hydroxyethyl methacrylate, tripropylene glycol diacrylate and p-hydroxyanisole are mixed at a mass ratio of 33:20:0.25.

[0013] Furthermore, the water-based flexible smooth matte coating comprises, by mass percentage, 15%~25% water-based acrylic resin emulsion, 2%~8% polyethylene wax emulsion, 5%~10% nano silica solution, 0.5%~3% metal soap, 0.5%~3% filler-type matting agent, 2%~10% pigments and fillers, 0.5%~1.5% silane coupling agent, 0.5%~1% softener, 0.1%~0.5% leveling agent, 3~9% acrylate copolymer crosslinked microspheres, and the balance being deionized water; the preparation steps of the acrylate copolymer crosslinked microspheres are as follows: Deionized water, hydroxypropyl methylcellulose, polyvinyl alcohol, cetyl alcohol, sodium nitrite, and sodium dodecylbenzenesulfonate were mixed and stirred at 2000-2100 rpm for 40-50 min at 20-25°C to obtain a mixture. Styrene, methyl methacrylate, and 1,4-butanediol dimethacrylate were added to the mixture, and the mixture was stirred and dispersed at 2000-2100 rpm for 1.2-1.5 h to obtain a mixed system. The mixed system was ultrasonically dispersed for 10-15 min to obtain a dispersed system. Benzoyl peroxide was added to the dispersed system, and the mixture was stirred at 250-300 rpm for 15-20 min in a water bath at 36-40°C. The temperature was then raised to 75-80°C and the stirring speed was maintained for 30-40 min. The temperature was further raised to 85-90°C and the stirring speed was maintained for 5-6 h. Ammonia was added to initiate a saponification reaction at 300-350 rpm for 2-2.5 h to obtain cross-linked acrylate copolymer microspheres.

[0014] Furthermore, the deionized water, hydroxypropyl methylcellulose, polyvinyl alcohol, cetyl alcohol, sodium nitrite, and sodium dodecylbenzene sulfonate are mixed in a mass ratio of 566.7:7.5:2.5:0.2:0.15:0.17, and styrene, methyl methacrylate, and 1,4-butanediol dimethacrylate are mixed in a mass ratio of 89:100:1.

[0015] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention describes a water-based flexible smooth matte coating and its preparation method. The coating uses water-based acrylic resin emulsion, polyethylene wax emulsion, and nano-silica solution as materials, and adds additives such as metal soap, filler-type matting agent, silane coupling agent, and acrylate copolymer crosslinked microspheres. The mixture is stirred to prepare a water-based flexible smooth matte coating for fiberglass cloth, achieving a soft, smooth, and matte finish while retaining the original strength of the fiberglass cloth.

[0016] 2. The present invention describes a water-based flexible smooth matte coating and its preparation method, which uses maleic anhydride-grafted polyethylene wax. By reacting the anhydride groups of maleic anhydride with the active sites on the polyethylene wax chain, carboxyl groups (-COOH) are introduced, which enhances the polarity and compatibility of the wax emulsion. It also migrates to the surface in synergy with phenyl silicone oil, reduces the coefficient of friction, and provides a long-lasting smooth touch and anti-blocking properties.

[0017] 3. This invention describes a water-based, flexible, smooth, matte coating and its preparation method. The method involves the condensation reaction of isophorone diisocyanate with the hydroxyl groups on the surface of nano-silica to form urethane bonds, grafting isophorone diisocyanate segments, and then end-capping with hydroxyethyl methacrylate to prepare polymer-grafted modified nano-silica. The modified nano-silica exhibits improved compatibility in emulsions, can be uniformly dispersed in the coating film, and enhances the hardness and abrasion resistance of the coating film.

[0018] 4. The present invention describes a water-based flexible smooth matte coating and its preparation method, which adds cross-linked microspheres of acrylate copolymer. During the preparation process, the double bonds of 1,4-butanediol dimethacrylate participate in the polymerization to form a three-dimensional cross-linked structure, which imparts mechanical strength to the coating film. When the cross-linked microspheres come into contact with water, the hydrophilic groups absorb water and swell, and shrink after losing water, forming a micro-rough surface, which enhances the matte effect and tactile feel. Moreover, the expansion-contraction characteristics of the microspheres adjust the microstructure of the coating film, adapt to changes in humidity, and prevent cracking. Detailed Implementation

[0019] Based on the embodiments of the present invention, all embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] In the following specific implementation, Calcium stearate: Product number S24307, sourced from Shanghai Yuanye Biotechnology Co., Ltd.; Talc powder: Product number S30618, sourced from Shanghai Yuanye Biotechnology Co., Ltd.; Styrene-modified acrylic emulsion: Product No. WD9411, sourced from Hubei Wande Chemical Co., Ltd.; Styrene: sourced from Nantong Zhonghe Chemical New Materials Co., Ltd.; Polyethylene wax: Product number Y45330, sourced from Shanghai Yuanye Biotechnology Co., Ltd.; Maleic anhydride: Product number 20250625999, sourced from Jinan Jinrihe Chemical Co., Ltd.; Benzoyl peroxide: Product number CDAA-220013, sourced from Shanghai Anpu Experimental Technology Co., Ltd.; γ-aminopropyltriethoxysilane: Product No. A00213, sourced from Wuhan Jiyesheng Chemical Co., Ltd.; Water-based black paste: sourced from Hebei Lanxiong Coatings Co., Ltd.; Phenyl silicone oil: Model SH-422, sourced from Shanghai Jiachen Chemical Co., Ltd.; Nano silica: Model HL-200, sourced from Hubei Huifu Nanomaterials Co., Ltd. Polypropylene glycol: Product number 1009310, sourced from Nantong Zhonghe Chemical New Materials Co., Ltd.; Isophorone diisocyanate: Product number js2024112703, sourced from Wuhan Jushun Chemical Co., Ltd.; Tripropylene glycol diacrylate: Product number ZS-11360, sourced from Shanghai Zhenzhun Biotechnology Co., Ltd.; Dibutyltin dilaurate: Product number WB00809, sourced from Guangdong Wengjiang Chemical Reagent Co., Ltd.; Hydroxyethyl methacrylate: Product number S24381, sourced from Shanghai Yuanye Biotechnology Co., Ltd.; p-Hydroxyanisole: Product No. S30255, sourced from Shanghai Yuanye Biotechnology Co., Ltd.; Organosilicon-modified acrylic leveling agent: Model HYCM-B550, sourced from Chongqing Heikemu New Material Technology Co., Ltd. Hydroxypropyl methylcellulose: Product No. S14173, sourced from Shanghai Yuanye Biotechnology Co., Ltd.; Polyvinyl alcohol: Product number S30196, sourced from Shanghai Yuanye Biotechnology Co., Ltd.; Cetyl alcohol: Product number S24198, sourced from Shanghai Yuanye Biotechnology Co., Ltd.; Sodium nitrite: Product number 202013, sourced from Jinan Jinhao Chemical Co., Ltd.; Sodium dodecylbenzenesulfonate: Product No. S15014, sourced from Shanghai Yuanye Biotechnology Co., Ltd.; Methyl methacrylate: Product number CIEQ-4-20006, sourced from Shanghai Anpu Experimental Technology Co., Ltd.; 1,4-Butanediol dimethacrylate: Product number S44448, sourced from Shanghai Yuanye Biotechnology Co., Ltd.; Ammonia, acetone, and xylene were all of analytical grade. Heavy calcium carbonate: 1250 mesh, sourced from Wuhan Jiyesheng Chemical Co., Ltd.; Silica powder: particle size 4~15μm, sourced from Fuchen (Tianjin) Chemical Reagent Co., Ltd.; Fiberglass cloth: Model 7628, sourced from Wuhan Jiyesheng Chemical Co., Ltd.

[0021] Example 1: A method for preparing a water-based, flexible, smooth, matte coating, comprising the following steps: Water-based flexible smooth matte coating composition: by weight percentage, 15% styrene-modified acrylic emulsion, 2% polyethylene wax emulsion, 5% nano silica solution, 0.5% calcium stearate, 0.5% talc, 2% water-based black paste, 0.5% γ-aminopropyltriethoxysilane, 0.5% SH-422 phenyl silicone oil, 0.1% organosilicon-modified acrylic leveling agent, 73.9% deionized water; Step 1: Sift the calcium stearate and talc powder separately and set aside; Step 2: Add half of the deionized water in the formula to a 20°C stirred tank. At 200 rpm, add styrene-modified acrylic emulsion, polyethylene wax emulsion and γ-aminopropyltriethoxysilane in sequence. After stirring for 15 minutes, add water-based black paste, calcium stearate and talc. Increase the speed to 800 rpm and stir for 10 minutes to ensure full dispersion. Add SH-422 phenyl silicone oil and the remaining deionized water. Adjust the speed to 400 rpm and stir for 5 minutes to form a homogeneous system. Step 3: Adjust the pH of the system to 7, add nano silica solution and organosilicon modified acrylic leveling agent in sequence, stir at 400 rpm for 10 min to obtain water-based flexible smooth matte coating.

[0022] Example 2: A method for preparing a water-based, flexible, smooth, matte coating, comprising the following steps: The composition of the water-based flexible smooth matte coating is as follows (by weight percentage): 20% styrene-modified acrylic emulsion, 4% polyethylene wax emulsion, 7% nano silica solution, 1% calcium stearate, 1% talc, 5% water-based black paste, 1% γ-aminopropyltriethoxysilane, 0.6% SH-422 phenyl silicone oil, 0.2% organosilicon-modified acrylic leveling agent, 3% acrylate copolymer crosslinked microspheres, and 57.2% deionized water. Step 1: Sift the calcium stearate and talc powder separately and set aside; Step 2: Add half of the deionized water in the formula to a stirred tank at 40°C. At 300 rpm, add styrene-modified acrylic emulsion, polyethylene wax emulsion and γ-aminopropyltriethoxysilane in sequence. After stirring continuously for 20 min, add water-based black paste, calcium stearate and talc. Increase the speed to 1000 rpm and stir for 15 min to ensure full dispersion. Add SH-422 phenyl silicone oil, acrylate copolymer crosslinked microspheres and the remaining deionized water. Adjust the speed to 600 rpm and stir for 10 min to form a homogeneous system. Step 3: Adjust the pH of the system to 8, add nano silica solution and organosilicon modified acrylic leveling agent in sequence, stir at 600 rpm for 15 min to obtain water-based flexible smooth matte coating; The polyethylene wax undergoes modification treatment, and the specific steps are as follows; Weigh 25g of polyethylene wax and 2.5g of maleic anhydride and add them to a 100mL four-necked flask. Add 25mL of acetone to the flask, heat to 50°C, and stir for 10min to ensure thorough mixing. Heat to 80°C and continue stirring until the acetone is completely evaporated. Then, purge with nitrogen to replace the oxygen in the system and continue heating to 110°C to completely melt the material. Add 0.15g of benzoyl peroxide and 38mL of xylene, heat to 138°C, and react for 3h to obtain a crude product. Transfer the crude product to a 250mL four-necked flask, add 38mL of xylene, heat in an oil bath until completely dissolved, reflux for 1h, and pour the hot solution into a beaker. Add acetone to precipitate the precipitate, and repeatedly filter, wash, and dry with acetone to obtain modified polyethylene wax. The nano-silica undergoes modification treatment, specifically through the following steps: Nano-silica and polypropylene glycol were mixed at a mass ratio of 0.7:49.3. The mixture was added to a 500 mL four-necked flask (equipped with N2 protection, a condenser, and a mechanical stirrer). The mixture was dehydrated under vacuum at 105 °C for 2 h. After cooling to 20 °C, 79.9 g of isophorone diisocyanate, 120.0 g of tripropylene glycol diacrylate, and 2 drops of dibutyltin dilaurate were added. The mixture was reacted at 80 °C for 3 h. After cooling the reaction system to 30 °C, 66.0 g of hydroxyethyl methacrylate, 40.0 g of tripropylene glycol diacrylate, 0.5 g of p-hydroxyanisole, and 4 drops of dibutyltin dilaurate were added. The mixture was heated to 80 °C and the reaction was continued. The disappearance of the isocyanate characteristic peak at 2270 cm⁻¹ was monitored by infrared spectroscopy. After the reaction was completed, modified nano-silica was obtained. The preparation steps of the acrylate copolymer crosslinked microspheres are as follows: Weigh out 566.7g of deionized water, 7.5g of hydroxypropyl methylcellulose, 2.5g of polyvinyl alcohol, 0.2g of cetyl alcohol, 0.15g of sodium nitrite, and 0.17g of sodium dodecylbenzenesulfonate. Stir at 2100 rpm for 40 minutes at 20℃ to ensure complete dissolution and mixing of all components, obtaining a mixture. Add 44.5g of styrene, 50.0g of methyl methacrylate, and 0.5g of 1,4-butanediol dimethacrylate to the mixture, and continue stirring and dispersing at 2100 rpm for 1.2 hours to obtain a mixed system. [The mixture is then...] The mixture was ultrasonically dispersed in a CNC ultrasonic cleaner for 10 minutes to obtain a dispersion system. The dispersion system was then transferred to a four-necked flask equipped with a spherical condenser, thermometer, and stirrer. 0.8 g of benzoyl peroxide was added, and the mixture was stirred at 250 rpm for 15 minutes in a 36°C water bath. The temperature was then raised to 75°C and maintained at 300 rpm for 30 minutes. The temperature was then raised to 85°C and maintained at 300 rpm for 5 hours. 5 g of ammonia was added to carry out a saponification reaction, which was carried out at 300 rpm for 2 hours to obtain cross-linked acrylate copolymer microspheres.

[0023] Example 3: A method for preparing a water-based, flexible, smooth, matte coating, comprising the following steps: The composition of the water-based flexible smooth matte coating is as follows (by weight percentage): 22% styrene-modified acrylic emulsion, 6% polyethylene wax emulsion, 8% nano silica solution, 1.5% calcium stearate, 1.5% talc, 7% water-based black paste, 1.2% γ-aminopropyltriethoxysilane, 0.8% SH-422 phenyl silicone oil, 0.3% organosilicon-modified acrylic leveling agent, 7% acrylate copolymer crosslinked microspheres, and 44.7% deionized water. Step 1: Sift the calcium stearate and talc powder separately and set aside; Step 2: Add half of the deionized water in the formula to a 50°C stirred tank. At 350 rpm, add styrene-modified acrylic emulsion, polyethylene wax emulsion and γ-aminopropyltriethoxysilane in sequence. After stirring for 25 min, add water-based black paste, calcium stearate and talc. Increase the speed to 1100 rpm and stir for 17 min to ensure full dispersion. Add SH-422 phenyl silicone oil, acrylate copolymer crosslinked microspheres and the remaining deionized water. Adjust the speed to 700 rpm and stir for 15 min to form a homogeneous system. Step 3: Adjust the pH of the system to 8.3, add nano silica solution and organosilicon modified acrylic leveling agent in sequence, stir at 700 rpm for 17 min to obtain water-based flexible smooth matte coating; The polyethylene wax undergoes modification treatment, and the specific steps are as follows; Weigh 25g of polyethylene wax and 0.25g of maleic anhydride and add them to a 100mL four-necked flask. Add 25mL of acetone to the flask, heat to 53°C, and stir for 13min to ensure thorough mixing. Heat to 83°C and continue stirring until the acetone is completely evaporated. Then, purge with nitrogen to replace the oxygen in the system and continue heating to 113°C to completely melt the material. Add 0.15g of benzoyl peroxide and 38mL of xylene, heat to 140°C, and react for 3.3h to obtain a crude product. Transfer the crude product to a 250mL four-necked flask, add 38mL of xylene, heat in an oil bath until completely dissolved, reflux for 1.3h, and pour the hot solution into a beaker. Add acetone to precipitate the precipitate, and repeatedly filter, wash, and dry with acetone to obtain modified polyethylene wax. The nano-silica undergoes modification treatment, specifically through the following steps: Nano-silica and polypropylene glycol were mixed at a mass ratio of 0.7:49.3. The mixture was added to a 500 mL four-necked flask (equipped with N2 protection, a condenser, and a mechanical stirrer). The mixture was dehydrated under vacuum at 107 °C for 2.3 h. After cooling to 23 °C, 79.9 g of isophorone diisocyanate, 120.0 g of tripropylene glycol diacrylate, and 3 drops of dibutyltin dilaurate were added. The mixture was reacted at 83 °C for 3.3 h. After cooling to 33 °C, 66.0 g of hydroxyethyl methacrylate, 40.0 g of tripropylene glycol diacrylate, 0.5 g of p-hydroxyanisole, and 5 drops of dibutyltin dilaurate were added. The mixture was heated to 83 °C and the reaction was continued. The disappearance of the isocyanate characteristic peak at 2270 cm⁻¹ was monitored by infrared spectroscopy. After the reaction was completed, modified nano-silica was obtained. The preparation steps of the acrylate copolymer crosslinked microspheres are as follows: Weigh out 566.7 g of deionized water, 7.5 g of hydroxypropyl methylcellulose, 2.5 g of polyvinyl alcohol, 0.2 g of cetyl alcohol, 0.15 g of sodium nitrite, and 0.17 g of sodium dodecylbenzenesulfonate. Stir at 2100 rpm for 45 min at 23 °C to ensure complete dissolution and mixing of all components, obtaining a mixture. Add 44.5 g of styrene, 50.0 g of methyl methacrylate, and 0.5 g of 1,4-butanediol dimethacrylate to the mixture, and continue stirring and dispersing at 2100 rpm for 1.4 h to obtain a mixed system. Place the mixed system in a suitable location... The dispersion system was obtained by ultrasonic dispersion treatment for 13 min in a CNC ultrasonic cleaner. The dispersion system was then transferred to a four-necked flask equipped with a spherical condenser, thermometer and stirrer. 0.8 g of benzoyl peroxide was added and stirred at 250 rpm for 17 min in a 38°C water bath. The temperature was raised to 77°C and maintained at 300 rpm for 35 min. The temperature was then raised to 87°C and maintained at 300 rpm for 5.5 h. 5 g of ammonia was added to carry out the saponification reaction and reacted at 300 rpm for 2.3 h to obtain cross-linked microspheres of acrylate copolymer.

[0024] Example 4: A method for preparing a water-based, flexible, smooth, matte coating, comprising the following steps: Water-based flexible smooth matte coating composition: by weight percentage, 25% styrene-modified acrylic emulsion, 8% polyethylene wax emulsion, 10% nano silica solution, 3% calcium stearate, 3% talc, 10% water-based black paste, 1.5% γ-aminopropyltriethoxysilane, 1% SH-422 phenyl silicone oil, 0.5% organosilicon-modified acrylic leveling agent, 9% acrylate copolymer crosslinked microspheres, 29% deionized water; Step 1: Sift the calcium stearate and talc powder separately and set aside; Step 2: Add half of the deionized water in the formula to a stirred tank at 60°C. At 400 rpm, add styrene-modified acrylic emulsion, polyethylene wax emulsion and γ-aminopropyltriethoxysilane in sequence. After stirring continuously for 30 min, add water-based black paste, calcium stearate and talc. Increase the speed to 1200 rpm and stir for 20 min to ensure full dispersion. Add SH-422 phenyl silicone oil, acrylate copolymer crosslinked microspheres and the remaining deionized water. Adjust the speed to 800 rpm and stir for 20 min to form a homogeneous system. Step 3: Adjust the pH of the system to 8.5, add nano silica solution and organosilicon modified acrylic leveling agent in sequence, stir at 800 rpm for 20 min to obtain water-based flexible smooth matte coating; The polyethylene wax undergoes modification treatment, and the specific steps are as follows: Weigh 25g of polyethylene wax and 0.25g of maleic anhydride and add them to a 100mL four-necked flask. Add 25mL of acetone to the flask, heat to 55°C, and stir for 15min to ensure thorough mixing. Heat to 85°C and continue stirring until the acetone is completely evaporated. Then, purge with nitrogen to replace the oxygen in the system and continue heating to 115°C to completely melt the material. Add 0.15g of benzoyl peroxide and 38mL of xylene, heat to 142°C, and react for 3.5h to obtain a crude product. Transfer the crude product to a 250mL four-necked flask, add 38mL of xylene, heat in an oil bath until completely dissolved, reflux for 1.5h, and pour the hot solution into a beaker. Add acetone to precipitate the precipitate, and repeatedly filter, wash, and dry with acetone to obtain modified polyethylene wax. The nano-silica undergoes modification treatment, specifically through the following steps: Nano-silica and polypropylene glycol were mixed at a mass ratio of 0.7:49.3. The mixture was added to a 500 mL four-necked flask (equipped with N2 protection, a condenser, and a mechanical stirrer). The mixture was dehydrated under vacuum at 110 °C for 2.5 h. After cooling to 25 °C, 79.9 g of isophorone diisocyanate, 120.0 g of tripropylene glycol diacrylate, and 4 drops of dibutyltin dilaurate were added. The mixture was reacted at 85 °C for 3.5 h. After cooling to 35 °C, 66.0 g of hydroxyethyl methacrylate, 40.0 g of tripropylene glycol diacrylate, 0.5 g of p-hydroxyanisole, and 6 drops of dibutyltin dilaurate were added. The mixture was heated to 85 °C and the reaction was continued. The disappearance of the isocyanate characteristic peak at 2270 cm⁻¹ was monitored by infrared spectroscopy. After the reaction was completed, modified nano-silica was obtained. The preparation steps of the acrylate copolymer crosslinked microspheres are as follows: Weigh out 566.7 g of deionized water, 7.5 g of hydroxypropyl methylcellulose, 2.5 g of polyvinyl alcohol, 0.2 g of cetyl alcohol, 0.15 g of sodium nitrite, and 0.17 g of sodium dodecylbenzenesulfonate. Stir at 2100 rpm for 50 min at 25 °C to ensure complete dissolution and mixing of all components, obtaining a mixture. Add 44.5 g of styrene, 50.0 g of methyl methacrylate, and 0.5 g of 1,4-butanediol dimethacrylate to the mixture, and continue stirring at 2100 rpm for 1.5 h to obtain a mixed system. [The text abruptly ends here, likely due to an incomplete translation or missing information.] The mixture was ultrasonically dispersed in a CNC ultrasonic cleaner for 15 minutes to obtain a dispersion system. The dispersion system was then transferred to a four-necked flask equipped with a spherical condenser, thermometer, and stirrer. 0.8 g of benzoyl peroxide was added, and the mixture was stirred at 250 rpm for 20 minutes in a 40°C water bath. The temperature was then raised to 80°C and maintained at 300 rpm for 40 minutes. The temperature was then raised to 90°C and maintained at 300 rpm for 6 hours. 5 g of ammonia was added to initiate a saponification reaction, which was carried out at 300 rpm for 2.5 hours to obtain cross-linked acrylate copolymer microspheres.

[0025] Comparative Example 1: The polyethylene wax emulsion, nano silica solution, calcium stearate and talc in the formulation of Example 1 were replaced with 10% heavy calcium carbonate (1250 mesh), while other reagents remained unchanged and other steps were the same as in Example 1.

[0026] Comparative Example 2: The polyethylene wax emulsion, nano silica solution, calcium stearate and talc in the formulation of Example 1 were replaced with 10% silica powder (particle size 4~15μm), while other reagents remained unchanged and other steps were the same as in Example 1.

[0027] Comparative Example 3: The acrylate copolymer cross-linked microspheres in the formulation of Example 4 were removed, while other reagents remained unchanged, and other steps were the same as in Example 4.

[0028] Experiment: Water-based flexible smooth matte coatings obtained in Examples 1-4 and Comparative Examples 1-3 were tested. Conventional 7628 type fiberglass cloth with a warp and weft density of 44×33 threads / inch and a surface density of 210 g / m² was selected. 2 The fabric was coated with seven different coatings, with a thickness of 0.2 mm. The coatings were applied to the fabric using padding and single-sided coating processes. The amount of coating was controlled, and the gloss, softness, smoothness and tensile strength of the finished fabric were tested. The padding process: The coatings used are the water-based flexible smooth matte coatings prepared in Examples 1-4 and Comparative Examples 1-3; one padding process is used, with three temperature zones of 130℃, 150℃ and 170℃ respectively, a machine speed of 4m / min, and the amount of adhesive applied to the finished product is controlled to be 7-8g. Single-sided coating process: The coatings used are those prepared in Examples 1-4 and Comparative Examples 1-3. Each coating has 1.2% of the total weight of PA thickener added. The coatings are stirred at 600 r / min for 20 minutes to obtain a water-based flexible smooth matte coating. One coat is applied to one side, with six temperature zones of 80℃, 100℃, 120℃, 180℃, 210℃, 220℃, and 185℃. The speed is 7-8 m / min, and the amount of adhesive applied to the finished product is controlled to be 7-8 g. Gloss test: GB / T 9754-2007 is used as the reference standard. The sample size is 150mm long and 100mm wide. Fracture strength and latitudinal fracture strength tests: GB / T 7690.3-2013 was used as the reference standard. The specimen size was 250 mm long and 25 mm wide. The tensile rate of the testing machine was 200 mm / min. The test results of the dipped samples are shown in Table 1, and the test results of the single-sided coated samples are shown in Table 2.

[0029] Table 1

[0030] Table 2

[0031] According to the data in Tables 1 and 2, the gloss of Examples 2-4 is much lower than that of Comparative Example 1, and slightly lower than that of Comparative Examples 2 and 3, regardless of whether it is the padding process or the single-sided coating process. This indicates that the cross-linked acrylate copolymer microspheres added in this invention can enhance the matte effect. The matte effect is much better than that of the conventional type coating of Comparative Example 1, and slightly better than that of the conventional matte coating of Comparative Example 2. Moreover, compared with Comparative Example 2, Examples 2-4 have a softer and smoother feel due to the modification of polyethylene wax and nano silica, and the damage to the overall tensile strength of the fiberglass cloth is smaller.

[0032] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A process for the preparation of an aqueous flexible, soft touch, matte coating characterized in that: Comprising the following steps: Step 1: Screen the metal soaps and the filler type matting agent separately for standby; Step 2: Add part of deionized water to a stirred tank at 20~60°C, add the water-based acrylic emulsion, polyethylene wax emulsion and silane coupling agent in turn under the speed of 200~400 rpm, continue stirring for 15~30 min, then add the pigment filler, metal soap and filler type matting agent, increase the stirring speed to 800~1200 rpm, stir for 10~20 min, add the softener and the remaining deionized water, adjust the stirring speed to 400~800 rpm, stir for 5~20 min to form a uniform system; Step 3: Adjust the pH of the system to 7~8.5, add the nano-silica solution and the leveling agent in turn, stir for 10~20 min under the speed of 400~800 rpm to prepare the water-based flexible smooth matte coating.

2. A process for the preparation of an aqueous flexible, soft touch, matte coating as claimed in claim 1, wherein: The water-based flexible smooth matte coating comprises 15%~25% water-based acrylic emulsion, 2%~8% polyethylene wax emulsion, 5%~10% nano-silica solution, 0.5%~3% metal soap, 0.5%~3% filler type matting agent, 2%~10% pigment filler, 0.5%~1.5% silane coupling agent, 0.5%~1% softener, 0.1%~0.5% leveling agent, and the balance is deionized water.

3. A process for the preparation of an aqueous flexible, soft touch, matte coating as claimed in claim 1, wherein: The water-based acrylic emulsion is a styrene modified acrylic emulsion with a solid content of 40%~50%; the polyethylene wax emulsion has a solid content of 30%~50%; the nano-silica solution has a pH value of 6~8, a solid content of 25%~40%, and a particle size of 5~50 nm.

4. The process for the preparation of an aqueous flexible, soft touch, matte coating as claimed in claim 1, wherein: The metal soap is a combination of one or more of zinc stearate, calcium stearate, magnesium stearate and aluminum stearate, and has a particle size of 3~5 μm; the filler type matting agent is a combination of one or more of talc, kaolin and diatomite, and has a particle size of 3~5 μm; the pigment filler is a water-based black paste; the silane coupling agent is a combination of one or more of amino silane coupling agent, epoxy silane coupling agent and vinyl silane coupling agent; the softener is a non-ionic phenyl silicone oil with a pH value of 6~7; and the leveling agent is a silicone modified acrylic leveling agent.

5. The process for the preparation of an aqueous flexible, soft touch, matte coating as claimed in claim 1, wherein: The polyethylene wax is modified as follows: Mix the polyethylene wax, maleic anhydride and acetone in a mass ratio of 10:1:10, heat to 50~55°C, stir for 10~15 min, heat to 80~85°C, continue stirring until the acetone is completely evaporated, then pass nitrogen, continue heating to 110~115°C, then add benzoyl peroxide and dimethylbenzene in turn, heat to 138~142°C, and react for 3~3.5 h to obtain the crude product; mix the crude product and dimethylbenzene, heat in an oil bath, reflux for 1~1.5 h, pour the solution into a beaker while hot, add acetone to precipitate the sediment, and repeatedly filter, wash and dry with acetone to obtain the modified polyethylene wax.

6. The process for preparing a water-based flexible, smooth, matte coating according to claim 1, characterized in that: The nano-silica is modified as follows: The nano-silica is mixed with polypropylene glycol, vacuum dewatered at 105-110℃ for 2-2.5h, cooled to 20-25℃, and then isophorone diisocyanate, tripropylene glycol diacrylate and dibutyl tin dilaurate are added, reacted at 80-85℃ for 3-3.5h, the reaction system is cooled to 30-35℃, and then hydroxyethyl methacrylate, tripropylene glycol diacrylate, p-hydroxyanisole and dibutyl tin dilaurate are added, warmed to 80-85℃, and the modified nano-silica is obtained after the reaction is completed.

7. A process for the preparation of an aqueous flexible, soft touch, matte coating according to claim 6, characterized in that: The nano-silica is mixed with polypropylene glycol at a mass ratio of 0.7:49.3, isophorone diisocyanate is mixed with tripropylene glycol diacrylate at a mass ratio of 2:3, and hydroxyethyl methacrylate is mixed with tripropylene glycol diacrylate and p-hydroxyanisole at a mass ratio of 33:20:0.

25.

8. A process for the preparation of an aqueous flexible, soft touch, matte coating as claimed in claim 1, wherein: The water-based flexible smooth matte paint composition comprises, by mass percentage, 15%-25% water-based acrylic resin emulsion, 2%-8% polyethylene wax emulsion, 5%-10% nano-silica solution, 0.5%-3% metal soap, 0.5%-3% filler-type matting agent, 2%-10% pigment filler, 0.5%-1.5% silane coupling agent, 0.5%-1% softener, 0.1%-0.5% leveling agent, 3-9% acrylate copolymer cross-linked microspheres, and the balance is deionized water; the preparation steps of the acrylate copolymer cross-linked microspheres are as follows: Deionized water, hydroxypropyl methyl cellulose, polyvinyl alcohol, cetyl alcohol, sodium nitrite and sodium dodecyl benzene sulfonate are mixed, stirred at a speed of 2000-2100 rpm at 20-25℃ for 40-50 min to obtain a mixed solution; styrene, methyl methacrylate and 1,4-butanediol dimethacrylate are added to the mixed solution, and stirring is continued at a speed of 2000-2100 rpm for 1.2-1.5 h to obtain a mixed system; the mixed system is subjected to ultrasonic dispersion treatment for 10-15 min to obtain a dispersion system; Peroxide is added to the dispersion system, stirred at a speed of 250-300 rpm in a water bath at 36-40℃ for 15-20 min, the temperature is raised to 75-80℃, the speed is maintained for 30-40 min, the temperature is further raised to 85-90℃, the speed is maintained for 5-6 h, and ammonia is added for saponification reaction, the speed is 300-350 rpm, and the reaction is carried out for 2-2.5 h to obtain acrylate copolymer cross-linked microspheres.

9. A process for the preparation of an aqueous flexible, soft touch, matte coating according to claim 8, characterized in that: The deionized water, hydroxypropyl methyl cellulose, polyvinyl alcohol, cetyl alcohol, sodium nitrite and sodium dodecyl benzene sulfonate are mixed at a mass ratio of 566.7:7.5:2.5:0.2:0.15:0.17, and the styrene, methyl methacrylate and 1,4-butanediol dimethacrylate are mixed at a mass ratio of 89:100:

1.

10. An aqueous flexible smooth matte paint prepared by the method according to any one of claims 1-9.

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