A method for preparing an aqueous architectural fluorescent paint

Abstract

The application provides a preparation method of a water-based architectural fluorescent paint, Eu 3+ ions are selected as raw materials for preparing hexagonal micro-nanometer flake europium-zinc ammonium phosphate particles red fluorescent powder, the material can be highly dispersed in a silicone-acrylate emulsion, and the europium-zinc ammonium phosphate fluorescent component is used as pigment, and the water-based silicone-acrylate emulsion is used as film-forming material, so that the corrosion-resistant, wear-resistant and water-based silicone-acrylate emulsion light-emitting paint is prepared.

Description

Technical Field

[0001] This invention belongs to the field of coating technology and relates to a method for preparing a water-based fluorescent architectural coating, which can be widely used in fields requiring bright and vivid colors, such as highways, railways, road signs, artificial landscapes, advertising signs, safety signs, traffic guardrails, underground parking lots, dance hall decoration, architectural decoration, fishing gear, etc. Background Technology

[0002] With the development of the building decoration industry, the coatings industry has also developed accordingly, and various functional coatings have appeared on the market, including fluorescent coatings. Rare earth luminescent materials, for example, are produced using rare earth elements, which belong to Group IIIB of the periodic table. These rare earth elements include scandium (Sc), yttrium (Y), and 15 lanthanide elements. Their similar atomic structures and ionic radii allow rare earth elements to substitute for each other at lattice sites, resulting in richer compound structures and wider applications.

[0003] The luminescence of rare earth ions mainly consists of two transitions: 4f→4f and 5d→4f. These transitions are primarily influenced by electric dipole interactions. According to spectral selection rules, electric dipole transitions are generally forbidden, but they are extremely sensitive to the symmetry of the crystal field. When the symmetry of the crystal field containing the rare earth ion deviates, this transition is permitted. Because the 4f-shell electrons are protected by the outer shell electrons and are not affected by the external crystal field, the spectral characteristics of the 4f→4f transition are mainly determined by the properties of the rare earth ion itself.

[0004] Among the lanthanides, europium (Eu) has the electron shell [Xe]4f. 7 6s 2 Eu is formed by losing the two outermost electrons and one electron from the penultimate shell. 3+ Ions. Because their crystal field environment is shielded by the outermost electrons, the effect on the 4f electron layer is slight; therefore, in Eu... 3+ In ions, the emission spectrum mainly consists of sharp line peaks from 4f→4f transitions, which appear as follows in the spectrum: 5 D0→ 7 F J Energy level transitions (J=0, 1, 2, 3, 4, 5, 6). Crystal field pair 5 The D0 level has a relatively small impact and cannot cause it to split, but it is significantly affected. 7 F J Energy levels are prone to splitting, and the number of splits in the F level increases with... 7 F J The symmetry of the lattice sites occupied by the energy levels decreases and their number increases. This is due to the Eu level. 3+ It is extremely sensitive to its crystal environment, so even slight changes in the environment can alter its transitions. When Eu 3+ When the ion is in a crystal lattice site with inversion symmetry, the orange magnetic dipole transition (5 D0→ 7 F1) Dominant Eu 3+ Emission of ions. When Eu3+ ions are in a non-inversion symmetric crystal lattice site, red electric dipole transitions dominate Eu3+ ion emission. 3+ The emission and transition of ions can very sensitively detect the signal of parity-selectivity prohibition being broken, and are also known as "hypersensitive transitions". Therefore, in most Eu... 3+ In the luminescence of ions, transition-driven emission accounts for the majority, Eu 3+ Eu ions typically emit red light. High color purity, a sharp, linear emission spectrum, and sensitivity to the crystal lattice make Eu ions... 3+ It is extremely popular among rare earth luminescent ions.

[0005] For example, CN101215470A discloses a europium-doped zinc ammonium phosphate orange-red luminescent powder material and its preparation method, published by Tongji University. This method employs a solvothermal reaction, controlling the synthesis of the zinc ammonium phosphate matrix by controlling the solvent, and using different surfactants to control the morphology of the product. By rationally controlling the reaction temperature, time, and other conditions, the orange-red luminescent material is obtained. The provided preparation method is simple, easy to implement, highly operable, controllable, and quantitative, and the resulting product exhibits good luminescent properties. The product obtained by this method has a regular morphology, and its morphology and luminescent properties show regular changes with changes in solvent and surfactant. The obtained product can be widely used in energy-saving fluorescent lamps, luminescent coatings, and other fields. While the solvothermal method effectively controls the product particle size and prepares high-purity phases, it requires high-temperature and high-pressure resistant synthesis equipment and a large amount of solvent templates, increasing product costs and complicating the process, which is not conducive to large-scale production.

[0006] For example, CN102775987B discloses a method for synthesizing manganese ion-doped zinc phosphate luminescent nanorods. Appropriate amounts of zinc nitrate and manganese nitrate are dissolved in deionized water to form a nitrate mixed solution. An appropriate amount of diammonium hydrogen phosphate solid is prepared into a 0.1 mol / L aqueous solution and added dropwise to the above nitrate mixed solution to form a suspension. The suspension is heated to 70℃, the pH is adjusted to 1-2, and rapid stirring is continued for 12 hours. The resulting precipitate is washed with ethanol and distilled water, centrifuged, and the precipitate is naturally dried at room temperature for 18-36 hours and then heat-treated at 600-1000℃ to obtain manganese ion-doped zinc phosphate nanorod crystals with a diameter of 50-100 nm and a length of 200-500 nm, exhibiting long afterglow luminescence.

[0007] For example, CN106243869B, Shanghai Beta Architectural Technology Co., Ltd., describes a sand-textured fluorescent water-based coating and its preparation method. The fluorescent coating comprises resin-coated fluorescent sand, wherein the resin-coated fluorescent sand is prepared from the following components: 30-60 mesh snowflake-white natural colored sand, resin adhesive, and fluorescent pigment. By coating the fluorescent pigment onto the surface of the sand, the instability of fluorescent pigments in water is solved, while simultaneously enhancing the wall decoration effect of the sand-textured coating, creating a three-dimensional fluorescent coating effect.

[0008] For example, CN107746708B discloses a red long-afterglow phosphor and its preparation method, aiming to provide a phosphor material with red long-afterglow luminescence properties, belonging to the field of phosphor technology. The general chemical formula of this phosphor is Sr. 3-x-y SiAlO5Cl3:xEu 2+ ,yRe 3+ Where Re is one or more combinations of Dy, Gd, and Nd, and the values ​​of x and y are in the ranges of 0.01≤x≤0.05 and 0.01≤y≤0.10, respectively. The luminescent center of this phosphor is Eu. 2+ Ions, through the introduction of Dy 3+ Gd 3+ and Nd 3+ Rare earth impurity ions can effectively enhance its long afterglow effect. The long afterglow phosphor provided by this invention has the characteristics of good chemical stability, high afterglow brightness, and long afterglow time, and can be used in decoration, emergency display and other fields.

[0009] For example, CN113025107B discloses a method for preparing a cuprous iodide-based hybrid fluorescent coating and its application. Cuprous iodide-based luminescent clusters are chemically bonded into the hybrid coating material, synthesizing an organic-inorganic hybrid functional coating with stable luminescent properties based on cuprous iodide clusters. The resulting hybrid fluorescent coating has many advantages, including simple preparation method and film-forming process, low cost, stable fluorescence performance, and large-scale production capability. It also provides corrosion protection and can be applied to decorative coatings via spin coating or blade coating. Furthermore, it can be applied to anti-counterfeiting and other fields using printing technology. This invention not only has significant scientific research value but also commercial potential and broad development prospects. Summary of the Invention

[0010] Based on the above understanding, this invention selects Eu 3+Ions were used as activators in the preparation of red phosphors to develop high-performance fluorescent coatings, specifically europium-zinc ammonium phosphate particles. Using [Rmim]BF4 ionic liquid as the electrolyte, zinc ions were provided through anodic dissolution. The cathode deposition of zinc ions was reduced by switching the power supply between the cathode and anode, forming a saturated Eu-doped zinc ammonium phosphate precursor in the electrolyte. The ionic liquid and aqueous solution were then separated by cooling to obtain a supersaturated precursor solution. Microwave synthesis was performed on the aqueous solution to obtain europium-zinc ammonium phosphate fluorescent components with a 200-400 nm micro-nano hexagonal sheet structure, which could be highly dispersed in a silicone-acrylic emulsion. Using the europium-zinc ammonium phosphate fluorescent component as a pigment and an aqueous silicone-acrylic emulsion as the film-forming material, an aqueous...

[0011] Silicone-acrylic emulsion luminescent coating.

[0012] Specifically:

[0013] A water-based fluorescent architectural coating composition is made from the following raw materials in parts by weight:

[0014] 40-50 parts silicone-acrylic emulsion, 25-30 parts 200-400nm europium-zinc ammonium phosphate particles, 5-10 parts 6-7μm talc powder, 5-10 parts 3-4μm kaolin, 0.8-1.2 parts BASF Tamol dispersant, 0.5-0.7 parts Huntsman PTF thickener, 0.3-0.5 parts SN-318 defoamer, 2-4 parts ethylene glycol diether or ester alcohol dodecyl film-forming aid, and 15-25 parts water.

[0015] A method for preparing a water-based fluorescent architectural coating includes the following steps:

[0016] (1) Add water to the high-speed dispersion tank, and add BASF Tamol dispersant and part of SN-318 defoamer in sequence under stirring conditions of 400-500 rpm, and continue stirring for 1-2 min;

[0017] (2) Increase the rotation speed to 1200-1400 rpm, and add 6-7 μm talc, 3-4 μm kaolin and 200-400 nm europium-zinc ammonium phosphate particles in sequence, and continue stirring for 10-20 min;

[0018] (3) Adjust the speed to 800-1000 rpm, add silicone acrylic emulsion, film-forming aid, Huntsman PTF thickener and the remaining defoamer in sequence, stir continuously for 10-20 minutes, stop stirring, let stand, filter to obtain the desired coating.

[0019] The europium-zinc ammonium phosphate particles are prepared by the following steps:

[0020] (1) Fluoroboric acid and chloro 1-alkyl-3-methyl imidazole are mixed uniformly after stirring at 42 DEG C for 12 hours at a mass ratio of 1:3, and the organic layer is extracted using methyl chloride, and an ionic liquid [Rmim]BF4 is obtained using a vacuum rotary evaporator;

[0021] (1) Under an inert atmosphere, 200 mL of ionic liquid [Rmim]BF4 is heated at 70-80 DEG C for 20-30 min, and then 100 mL of deionized water, 1.5-2.2 g of Eu(NO3)3.6H2O and 5-6 g of ammonium dihydrogen phosphate are slowly added, and mechanical stirring is combined with ultrasonic stirring for 30-40 min to obtain an ionic liquid electrolyte;

[0022] (2) A high-purity zinc electrode and a platinum plate counter electrode are inserted into the above electrolyte, and then electrolysis is carried out under an inert atmosphere, with the temperature controlled at 70-80 DEG C, a switchable direct current power source used, high-purity zinc as the anode, a platinum plate as the cathode, a voltage of 4-5 V, and a time of 3-5 min; the current direction is switched, with high-purity zinc as the cathode and a platinum plate as the anode, a voltage of 1-2 V, and a time of 0.5-1 min; the electrolysis treatment cycle is 15-20 times;

[0023] (3) The electrolyte is discharged, stirred at 100-200 rpm for 10-15 min, cooled to 2-3 DEG C, and placed at a constant temperature for 24 h, and then separated into layers, and the upper liquid is taken;

[0024] (4) The upper liquid is placed in a microwave reactor for microwave treatment, with the microwave treatment conditions being stirring at 80-100 rpm, a microwave power of 240-480 W, and a time of 20-30 min, followed by natural cooling, and the microwave-treated liquid is subjected to centrifugation and filtration treatment, the solid is washed with deionized water and ethanol in sequence, and vacuum drying is carried out to obtain europium-zinc ammonium phosphate particles.

[0025] Beneficial technical effects: (1) The europium-zinc ammonium phosphate fluorescent particles prepared by the present application have good dispersibility and compatibility, weather resistance, and excellent wear resistance and corrosion resistance in the coating emulsion; (2) Zinc ions are slowly provided by anodic dissolution, and then the zinc ions are free in the aqueous solution of ionic liquid [Rmim]BF4, and then the precursor of europium-zinc ammonium phosphate is forced into the aqueous solution by cooling to form a supersaturated solution, and then hexagonal flake-shaped micro-nano europium-zinc ammonium phosphate fluorescent particles are obtained by microwave treatment, as shown in Figure 1 ; the fluorescent particles have high color development; (3) The power source control affects the doping effect or doping amount of rare earth europium in zinc ammonium phosphate, directly affecting the emission light and excitation light intensity, and ultimately affecting the red light effect of the fluorescent coating; (4) The morphology and purity of the europium-zinc ammonium phosphate crystals are controlled by electrolysis, significantly enhancing the luminescent properties of the red fluorescent material. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 2 shows the excitation spectrum (PLE) of the red fluorescent material prepared in Example 2. Figure 1 Figure 3 shows the emission spectrum (PL) of the red fluorescent material prepared in Example 2. Figure 4 shows the color coordinate diagram of the red fluorescent material prepared in Example 2.

[0027] Figure 5 shows the excitation spectrum (PLE) of the red fluorescent material prepared in Example 2 and Comparative Example 1. Figure 2 Figure 6 shows the emission spectrum (PL) of the red fluorescent material prepared in Example 2 and Comparative Example 1.

[0028] Figure 7 shows the color coordinate diagram of the red fluorescent material prepared in Example 2 and Comparative Example 1. Figure 3

[0029] Figure 4 Figure 8 shows the color coordinate diagram of the red fluorescent material prepared in Example 2 and Comparative Example 1. DETAILED DESCRIPTION Example 1

[0030] A method for preparing europium-zinc ammonium phosphate particles, comprising the following steps:

[0031] (1) uniformly mix fluoroboric acid and chloro-1-alkyl-3-methyl imidazole in a mass ratio of 1:3 at 42°C for 12 h, extract the organic layer using methyl chloride, and obtain the ionic liquid [Rmim]BF4 using a vacuum rotary evaporator;

[0032] (1) under an inert atmosphere, heat 200 mL of the ionic liquid [Rmim]BF4 at 70°C for 20 min, then slowly add 100 mL of deionized water, 1.5 g of Eu(NO3)3·6H2O, and 5 g of ammonium dihydrogen phosphate, and mechanically stir and ultrasonically stir for 30 min to obtain an ionic liquid electrolyte;

[0033] (2) insert a high-purity zinc working electrode and a platinum plate counter electrode into the electrolyte, then perform electrolysis under an inert atmosphere, control the temperature to be 70°C, use a switchable direct current power supply, use high-purity zinc as the anode and platinum as the cathode, the voltage is 4V, the time is 3 min; switch the current direction, use high-purity zinc as the cathode and platinum as the anode, the voltage is 1V, the time is 0.5 min; the electrolysis cycle is 15 times;

[0034] (3) discharge the electrolyte, continuously stir at 100 rpm for 10 min, cool to 2°C, and place at a constant temperature for 24 h, then separate the layers and take the upper liquid;

[0035] (4) place the upper liquid in a microwave reactor for microwave treatment, the microwave treatment conditions are: stirring at 80 rpm, microwave power is 240W, time is 20 min, then naturally cool, centrifuge and filter the microwave-treated liquid, wash the solid with deionized water and ethanol in sequence, and vacuum dry to obtain europium-zinc ammonium phosphate particles. Example 2

[0036] ​A preparation method of europium-zinc ammonium phosphate particles is prepared by the following steps:

[0037] (1) Fluoroboric acid and chloro-1-alkyl-3-methyl imidazole are mixed uniformly at a mass ratio of 1:3 after stirring at 42°C for 12h, and the organic layer is extracted with methyl chloride, and an ionic liquid [Rmim]BF4 is obtained using a vacuum rotary evaporator;

[0038] (1) Under an inert atmosphere, 200mL of ionic liquid [Rmim]BF4 is heated at 75°C for 25min, then 100mL of deionized water, 1.85g of Eu(NO3)3·6H2O and 5.5g of ammonium dihydrogen phosphate are slowly added, and mechanical stirring is added to ultrasonic stirring for 35min to obtain an ionic liquid electrolyte;

[0039] (2) A high-purity zinc electrode and a platinum plate are inserted into the above electrolyte, and then electrolysis is carried out under an inert atmosphere, with a temperature control of 75°C, a switchable direct current power supply, a high-purity zinc anode, a platinum plate cathode, a voltage of 4.5V, and a time of 4min; switch the current direction, with a high-purity zinc cathode, a platinum plate anode, a voltage of 1.5V, and a time of 0.75min; the electrolysis treatment cycle is 17 times;

[0040] (3) The electrolyte is discharged, continuously stirred at 150rpm for 12.5min, cooled to 2.5°C, and placed at a constant temperature for 24h, then separated into layers, and the upper liquid is taken;

[0041] (4) The upper liquid is placed in a microwave reactor for microwave treatment, with a stirring speed of 90rpm, a microwave power of 360W, and a time of 25min, then naturally cooled, and the microwave-treated liquid is subjected to centrifugal and filtration treatment, the solid is washed with deionized water and ethanol in sequence, and vacuum dried to obtain europium-zinc ammonium phosphate particles. Example 3

[0042] A preparation method of europium-zinc ammonium phosphate particles is prepared by the following steps:

[0043] (1) Fluoroboric acid and chloro-1-alkyl-3-methyl imidazole are mixed uniformly at a mass ratio of 1:3 after stirring at 42°C for 12h, and the organic layer is extracted with methyl chloride, and an ionic liquid [Rmim]BF4 is obtained using a vacuum rotary evaporator;

[0044] (1) Under an inert atmosphere, 200mL of ionic liquid [Rmim]BF4 is heated at 75°C for 25min, then 100mL of deionized water, 1.85g of Eu(NO3)3·6H2O and 5.5g of ammonium dihydrogen phosphate are slowly added, and mechanical stirring is added to ultrasonic stirring for 35min to obtain an ionic liquid electrolyte;

[0045] (2) high-purity zinc as the working electrode and platinum as the counter electrode are inserted into the electrolyte, and then electrolysis treatment is carried out under an inert atmosphere, with the temperature controlled at 80°C, a switchable direct current power source used, high-purity zinc as the anode, platinum as the cathode, the voltage at 5V, the time at 5min; the current direction switched, high-purity zinc as the cathode, platinum as the anode, the voltage at 2V, the time at 1min; the electrolysis treatment cycle at 20 times;

[0046] (3) the electrolyte is discharged, stirring is carried out at 200rpm for 15min, the temperature is lowered to 3°C, constant-temperature placement is carried out for 24h, the layers are separated, and the upper liquid is taken;

[0047] (4) the upper liquid is placed in a microwave reactor for microwave treatment, the microwave treatment conditions are: stirring at 100rpm, microwave power at 480W, the time at 30min, and natural cooling after the treatment; the microwave-treated liquid is subjected to centrifugal and filtration treatment, the solid is washed with deionized water and ethanol in sequence, and vacuum drying is carried out, to obtain europium-zinc ammonium phosphate particles.

[0048] Comparative Example 1, a preparation method of europium-zinc ammonium phosphate particles, is prepared by the following steps:

[0049] (1) fluoroboric acid and chloro 1-alkyl-3-methyl imidazole are mixed uniformly after stirring at 42°C for 12h according to a mass ratio of 1:3, chloromethane is used to extract the organic layer, and a vacuum rotary evaporator is used to obtain ionic liquid [Rmim]BF4;

[0050] (1) under an inert atmosphere, 200mL of ionic liquid [Rmim]BF4 is heated at 75°C for 25min, and then 100mL of deionized water, 1.85g of Eu(NO3)3·6H2O and 5.5g of ammonium dihydrogen phosphate are slowly added, mechanical stirring is combined with ultrasonic stirring for 35min, to obtain an ionic liquid electrolyte;

[0051] (2) high-purity zinc as the working electrode and platinum as the counter electrode are inserted into the electrolyte, and then electrolysis treatment is carried out under an inert atmosphere, with the temperature controlled at 75°C, a switchable direct current power source used, high-purity zinc as the anode, platinum as the cathode, the voltage at 4.5V, the time at 68min;

[0052] (3) the electrolyte is discharged, stirring is carried out at 150rpm for 12.5min, the temperature is lowered to 2.5°C, constant-temperature placement is carried out for 24h, the layers are separated, and the upper liquid is taken;

[0053] (4) the upper liquid is placed in a microwave reactor for microwave treatment, the microwave treatment conditions are: stirring at 90rpm, microwave power at 360W, the time at 25min, and natural cooling after the treatment; the microwave-treated liquid is subjected to centrifugal and filtration treatment, the solid is washed with deionized water and ethanol in sequence, and vacuum drying is carried out, to obtain europium-zinc ammonium phosphate particles.

[0054] Excitation spectrum: refers to the intensity of a certain spectral line or band of luminescence changes with the wavelength (or frequency) of excitation light, and the excitation spectrum reflects the effect of light of different wavelengths on the material.

[0055] Emission spectrum: emission spectrum is also called luminescence spectrum, and the emission spectrum of luminescent material refers to the distribution of luminescent energy by wavelength or frequency, which is often represented by a curve. Test of excitation and emission spectrum performance: Hitachi F-4500 fluorescence spectrometer was used to measure the excitation spectrum and emission spectrum of the luminescent powder. The light source was a 150W xenon lamp, the monochromator slit width was 0.5mm, and the scanning step was 1nm.

[0056] 0.5mm, and the scanning step was 1nm.

[0057] From the PLE test attached Figure 2 , it can be seen that the excitation peak of Example 2 (black line) and Comparative Example 2 (blue line) is in the range of 310-570nm, and the strongest excitation peak is at 390nm. From the PL test attached Figure 3 , it can be seen that the emission spectrum peaks of Example 2 (red) and Comparative Example 2 (blue-green) are mainly concentrated at 590, 614, 651 and 690nm, respectively, which correspond to 5 D0 → 7 F1, 5 D0→ 7 F2, 5 D0 → 7 F3, 5 D0 → 7 F4, wherein the emission peak area of Example 2 is 1.42 times that of Comparative Example 2. The prepared near-ultraviolet excited red fluorescent powder can effectively emit red light under 390nm excitation, as shown in Figure 4 , the CIE color coordinates are in the red light region (x=0.6351, y=0.3409), indicating that the sample has high color rendering property. Example 4

[0058] A preparation method of a water-based architectural fluorescent coating comprises the following steps:

[0059] (1) Add water to a high-speed dispersion cylinder, and then add Basf Tamol dispersant, part of SN-318 defoamer, under the condition of 450rpm stirring, and continue stirring for 1.5min;

[0060] (2) Increase the speed to 1100rpm, and then add 6-7μm talc, 3-4μm kaolin and 200-400nm europium-zinc ammonium phosphate particles, and continue stirring for 15min;

[0061] (3) Adjust the speed to 900 rpm, and then add the silicone-acrylate emulsion, the film forming agent, the Hensyl PTF thickener and the rest of the defoaming agent successively, and continue to stir for 15 min. Stop stirring, stand still, filter to obtain the desired paint.

[0062] An aqueous architectural fluorescent paint composition was prepared from the following raw materials by weight:

[0063] Silicone-acrylate emulsion 45 parts, 200-400 nm europium-zinc ammonium phosphate particles prepared in Example 2 28 parts, 6-7 μm talc 7.5 parts, 3-4 μm kaolin 7.5 parts, BASF Tamol dispersant 1 part, Hensyl PTF thickener 0.6 part, SN-318 defoaming agent 0.4 part, ethylene glycol diether or fatty alcohol twelve film forming agent 3 parts, water 20 parts.

[0064] Comparative Example 2, an aqueous architectural fluorescent paint composition was prepared from the following raw materials by weight:

[0065] Silicone-acrylate emulsion 45 parts, 200-400 nm europium-zinc ammonium phosphate particles prepared in Comparative Example 1 28 parts, 6-7 μm talc 7.5 parts, 3-4 μm kaolin 7.5 parts, BASF Tamol dispersant 1 part, Hensyl PTF thickener 0.6 part, SN-318 defoaming agent 0.4 part, ethylene glycol diether or fatty alcohol twelve film forming agent 3 parts, water 20 parts.

[0066] The steps include:

[0067] (1) Add water to a high-speed dispersion cylinder, and then add the BASF Tamol dispersant and part of the SN-318 defoaming agent successively at intervals under the condition of stirring at 450 rpm, and continue to stir for 1.5 min;

[0068] (2) Increase the speed to 1100 rpm, and then add the 6-7 μm talc, the 3-4 μm kaolin and the 200-400 nm europium-zinc ammonium phosphate particles successively at intervals, and continue to stir for 15 min;

[0069] (3) Adjust the speed to 900 rpm, and then add the silicone-acrylate emulsion, the film forming agent, the Hensyl PTF thickener and the rest of the defoaming agent successively, and continue to stir for 15 min. Stop stirring, stand still, filter to obtain the desired paint.

[0070] The coating prepared in Example 4 and Comparative Example 2 was sprayed on the surface of a substrate for several times, and after each spraying, the coating was dried in an oven at 50°C for 0.5 h, and then the coating was sprayed again and dried. The coating thickness was 10 microns. The abrasion resistance of each coating was determined according to the measurement method in the national standard GB 1768-79, and the operation was as follows: the steel substrate with the coating was fixed on the working turntable of the abrasion tester, 500 g of effective load was applied on the pressurized arm, and the steel substrate was polished for 500 cycles at the same speed. The weight loss was calculated by weighing the same weight. The weight loss of Example 4 was 0.0083 g, and the weight loss of Comparative Example 2 was 0.0089 g. The abrasion resistance of the two coatings was not significantly different, and Example 4 was more excellent. The corrosion resistance of the two coatings was tested, and the corrosion potential of Example 4 was -623 mV, and the corrosion current density was 2.738*10 -8 A / cm. The corrosion potential of Comparative Example 3 was -659 mV, and the corrosion current density was 13.287*10 -8 A / cm. Example 4 was more excellent in corrosion resistance, which indicated that the dispersibility of the fluorescent particles prepared in Example 2 in the coating or the combination effect of the particles and the coating was more excellent. The emission spectrum and the excitation spectrum of the fluorescent material in Example 4 and Comparative Example 2 were tested, and the main peak positions of the emission light and the excitation light of the two were not changed, and only the intensity was reduced. The emission light intensity of Comparative Example 2 was lost by about 6.3% compared with Example 2, and the excitation light intensity was lost by about 8.9%. The main reason was that the coating layer reflected or absorbed part of the incident light, so that the light energy absorbed by the fluorescent particles was reduced, and the fluorescent light emitted was weakened.

[0071] The above-described examples only express certain embodiments of the present application, and the description is more specific and detailed, but it should not be understood as limiting the scope of the present patent; it should be noted that for ordinary skilled persons in the art, several modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application; therefore, the protection scope of the present patent should be subject to the appended claims.

Claims

1. A method for preparing a water-based fluorescent architectural coating, characterized in that... Includes the following steps: (a) Add water to the high-speed dispersion tank, and add BASF Tamol dispersant and part of SN-318 defoamer in sequence at intervals while stirring at 400-500 rpm, and continue stirring for 1-2 min; (b) Increase the rotation speed to 1200-1400 rpm, and add 6-7 μm talc, 3-4 μm kaolin and 200-400 nm europium-zinc ammonium phosphate particles in sequence, stirring continuously for 10-20 min; (c) Adjust the speed to 800-1000 rpm, add silicone-acrylic emulsion, film-forming aid, thickener and remaining defoamer in sequence, stir continuously for 10-20 minutes, stop stirring, let stand, filter to obtain the desired coating; The europium-zinc ammonium phosphate particles are prepared by the following steps: (1) Fluoroboric acid and chloro-1-alkyl-3-methylimidazolium were stirred at 42°C for 12 h at a mass ratio of 1:3 and mixed evenly. The organic layer was extracted with chloromethane and the ionic liquid [Rmim]BF4 was obtained by vacuum rotary evaporation. (2) Under an inert atmosphere, heat 200 mL of ionic liquid [Rmim]BF4 at 70-80℃ for 20-30 min, then slowly add 100 mL of deionized water, 1.5-2.2 g of Eu(NO3)3·6H2O and 5-6 g of ammonium dihydrogen phosphate, and mechanically stir and ultrasonically stir for 30-40 min to obtain the ionic liquid electrolyte; (3) Using high-purity zinc as the working electrode and platinum sheet as the counter electrode, insert it into the above electrolyte, and then perform electrolysis under an inert atmosphere. Control the temperature at 70-80℃. Use a switchable DC power supply. Use high-purity zinc as the anode and platinum sheet as the cathode. The voltage is 4-5V and the time is 3-5min. Switch the current direction. Use high-purity zinc as the cathode and platinum sheet as the anode. The voltage is 1-2V and the time is 0.5-1min. The electrolysis cycle is 15-20 times. (4) Remove the electrolyte, stir continuously at 100-200 rpm for 10-15 min, cool to 2-3℃, keep at constant temperature for 24 h, separate into layers, and take the supernatant; (5) Place the liquid in a microwave reactor for microwave treatment. Microwave treatment conditions: stirring at 80-100 rpm, microwave power of 240-480W, time of 20-30 min, and then cool naturally. Centrifuge and filter the microwave-treated liquid. Wash the solid with deionized water and ethanol in sequence, and then dry it under vacuum to obtain europium-zinc ammonium phosphate particles with hexagonal sheet structure.

2. The preparation method of a water-based architectural fluorescent coating as described in claim 1, characterized in that... The film-forming aid is ethylene glycol diether.

3. The preparation method of a water-based architectural fluorescent coating as described in claim 2, characterized in that... The thickener is Huntsman PTF thickener.

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