Polyester finish paint for building curtain wall aluminum veneer

Abstract

The invention belongs to the field of functional coatings, and particularly relates to a polyester finishing coat for a building curtain wall aluminum veneer and a preparation method of the polyester finishing coat for the building curtain wall aluminum veneer, and the polyester finishing coat for the building curtain wall aluminum veneer comprises the following raw materials in parts by weight: 20-30 parts of saturated polyester resin; 10 to 15 parts of functional resin I; 3.0 to 5.0 parts of functional resin II; 5.0 to 9.0 parts of amino resin; 15 to 25 parts of pigment; 12 to 20 parts of filler; 0.2 to 0.5 part of a dispersant; 0.1 to 0.3 part of an anti-settling agent; 0.1 to 0.2 part of a defoaming agent; 0.5 to 1.0 part of a leveling agent; 10 to 15 parts of an S-150 solvent; the saturated polyester resin, the functional resin I, the functional resin II and the amino resin are all metered by solid parts; the components are subjected to a paint preparation process, a spraying process, baking and curing to obtain the polyester finish paint for the aluminum veneer of the building curtain wall. According to the polyester finishing paint for the building curtain wall aluminum veneer, through formula design, the problem that in the prior art, polyester finishing paint for the aluminum veneer is poor in chemical resistance can be effectively solved.

Description

Technical Field

[0001] The present invention belongs to the field of functional coatings, and particularly relates to a polyester topcoat for aluminum veneers of building curtain walls. Background Art

[0002] Due to its good decorative effect, stable material and other characteristics, aluminum veneer curtain walls are popular in the construction industry. However, problems may also occur during its development. Among them, problems such as corrosion and lack of durability have attracted people's attention. Therefore, the importance of coatings for aluminum veneers of building curtain walls is self-evident.

[0003] During normal use, over time, the surface coating of the building curtain wall will experience phenomena such as loss of gloss, color change, peeling and powdering in the atmospheric environment, resulting in the exposure of the curtain wall substrate. When the curtain wall substrate comes into contact with corrosive media in the environment, chemical or electrochemical reactions occur and it is corroded, its performance deteriorates, and even is damaged. Therefore, the anti-corrosion technology of the curtain wall substrate plays an extremely important role in the safety performance and durability of the curtain wall substrate.

[0004] Coatings for aluminum veneers of building curtain walls include primers directly coated on the surface of aluminum veneers to form a bottom coating and topcoats coated on the outermost layer to form a surface coating, etc. The coatings of each layer play a very important role in the protection of the structure. Traditional topcoats for aluminum veneers of building curtain walls have the following problems: The single polyester / amino system has a certain weather resistance, but there is still a need for improvement, and there is a problem of poor chemical resistance, which easily leads to a decline in the performance of the paint film and limited durability. Summary of the Invention

[0005] The purpose of the present invention is to provide a polyester topcoat for aluminum veneers of building curtain walls and its preparation method in view of the problem of poor chemical resistance of polyester topcoats for aluminum veneers of building curtain walls in the prior art. Through formula design and self-made functional resin I and functional resin II, prepared by the paint-making process, while solving the problem of chemical resistance, it also has excellent stain resistance, impact resistance and other properties. To achieve the above purpose, the technical solutions adopted by the present invention to solve its technical problems are as follows: The present invention provides a polyester topcoat for aluminum veneers of building curtain walls, comprising the following raw materials in parts by weight: Saturated polyester resin 20 - 30 parts; Functional resin I 10 - 15 parts; Functional resin II 3.0 - 5.0 parts; Amino resin 5.0 - 9.0 parts; Pigment 15 - 25 parts; Filler 12 - 20 parts; Dispersant 0.2 - 0.5 part; Anti-settling agent 0.1 - 0.3 part; Defoamer: 0.1 - 0.2 parts; Leveling agent: 0.5 - 1.0 parts; S - 150 solvent: 10 - 15 parts; The saturated polyester resin, functional resin I, functional resin II, and amino resin are all calculated based on solid content; For the functional resin I, its preparation method includes the following steps: S11: Coupling reaction of 2,4,4'-trihydroxybenzophenone derivative and bromoethanol to obtain intermediate 1I; The molar ratio of the 2,4,4'-trihydroxybenzophenone derivative to bromoethanol is 1:2; S12: Polycondensation reaction of intermediate 1I, polyfluorodiol, ethylene glycol, glycerol, and terephthalic acid under the action of a catalyst to obtain the target product, i.e., functional resin I; The total molar ratio of intermediate 1I, polyfluorodiol, ethylene glycol, and glycerol to terephthalic acid is 1.1:1; and The molar ratio of intermediate 1I, polyfluorodiol, ethylene glycol, and glycerol is 0.05 - 0.15:0.60 - 0.80:0.05 - 0.15:0.10 - 0.20; For the functional resin II, its preparation method includes the following steps: S21: Coupling reaction of nano - silicon and silane coupling agent containing carbon - carbon double bond to obtain intermediate 2I; The dosage ratio of nano - silicon to silane coupling agent containing carbon - carbon double bond is 1g:0.1 - 0.3g; S22: Nucleophilic addition reaction of fluorinated acyl chloride and hydroxy - olefins to obtain intermediate 2II; The dosage ratio of fluorinated acyl chloride to hydroxy - olefins is added according to the molar ratio of acyl chloride to hydroxyl group of 1:1; S23: Nucleophilic addition reaction of isocyano - olefins and phenol under the action of inhibitor and catalyst to obtain intermediate 2III; The dosage ratio of isocyano - olefins to phenol is added according to the molar ratio of isocyanate group to hydroxyl group of 1:1; S24: Free - radical polymerization reaction of intermediate 2I, intermediate 2II, intermediate 2III, and acrylate under the action of an initiator to obtain the target product, i.e., functional resin II; The dosage ratio of intermediate 2I, intermediate 2II, intermediate 2III, and acrylate is 0.15g:0.60 - 0.80g:0.20 - 0.30g:0.10 - 0.20g.

[0006] Furthermore, The 2,4,4'-trihydroxybenzophenone derivative is 2,4,4'-trihydroxybenzophenone or 2,2',4,4'-tetrahydroxybenzophenone.

[0007] Further, the polyfluorodiol is 1H,1H,9H,9H-perfluoro-1,9-nonanediol or octafluoro-1,6-hexanediol.

[0008] Further, the fluorinated acyl chloride is perfluorobutyryl chloride, perfluorooctanoyl chloride or perfluorononanoyl chloride; and the hydroxyalkene is an allyl hydroxy structure or a hydroxyacrylate structure.

[0009] Further, the isocyanoalkene is allyl isocyanate or acryloyloxy isocyanate.

[0010] Further, the acrylate is a hard monomer acrylate.

[0011] Further, the hydroxyl value of the saturated polyester resin is a medium hydroxyl polyester.

[0012] Further, the amino resin is a mixture of a fully methylated amino resin and a partially methylated amino resin.

[0013] Further, the pigment is an inorganic pigment.

[0014] Another object of the present invention is to provide a preparation method of a polyester topcoat for an aluminum single panel of a building curtain wall, comprising the following steps: S31, paint formulation, that is, Take a part of the saturated polyester resin in the formula amount, and sequentially add the S-150 aromatic hydrocarbon solvent in the formula amount, the functional resin I in the formula amount, the dispersant in the formula amount, the anti-settling agent in the formula amount, the pigment in the formula amount and the filler in the formula amount under low-speed stirring, and then stir at high speed for 20-30 min to obtain a premixed liquid I; S32, grinding, that is, Transfer the premixed liquid I to a grinding machine and grind it until a mixed liquid II with a solid particle fineness ≤ 20 μm is obtained; S33, add the remaining raw materials and dilute, that is, Stir the mixed liquid II at low speed, and sequentially add the remaining saturated polyester resin, the amino resin in the formula amount, the functional resin II in the formula amount, and the leveling agent in the formula amount; adjust the viscosity of the mixed liquid with an appropriate amount of ethylene glycol monobutyl ether and continue to stir at low speed for 8-12 min to obtain a mixed liquid III; S34, filtering and collecting, that is, Filter the mixed liquid III with a filter bag with a pore size of 50 μm, and the filtrate is the polyester topcoat for the aluminum single panel of the building curtain wall.

[0015] Another object of the present invention is to provide a polyester topcoat for building curtain wall aluminum veneer for use in rolled aluminum curtain wall.

[0016] The present invention has the following beneficial effects: (1) The present invention provides a polyester topcoat for building curtain wall aluminum veneer, wherein the main resin is a polyester amino system. On the one hand, the polyester structure has a certain flexibility and can meet the installation and processing requirements of metal products; on the other hand, the polyester structure has excellent gloss and excellent decorative properties.

[0017] (2) The present invention provides a polyester topcoat for building curtain wall aluminum veneer, one of the components of which is a functional resin I, which is a polyester resin containing a large number of CF bonds and structures such as o-hydroxybenzophenone and hydroxyl in the main chain structure. First, the functional resin I is also a polyester structure and has excellent dispersibility in the system; second, the large number of CF bonds in the functional resin I, in which F has a low atomic surface energy, can migrate to the surface and enrich, has a high hydrophobic effect, and has anti-fouling properties; third, the large number of CF bonds in the functional resin I, in which CF has a large bond energy, has a high weather resistance effect; fourth, the o-hydroxybenzophenone structure in the functional resin I has a high efficiency of ultraviolet absorption, which can effectively improve the weather resistance of the topcoat; fifth, the functional resin I can provide a reaction with a curing agent to improve the physical properties of the topcoat, such as hardness, scratch resistance, and anti-aging performance.

[0018] (3) The present invention provides a polyester topcoat for aluminum veneer of building curtain wall, wherein one of its components, functional resin II, is a hyperbranched structure of nano-silicon embedded in an organic polymer chain, wherein the organic polymer chain contains a silane coupling agent structure, a CF bond, a carbamate and a hard monomer acrylate structure. First, the nano-silicon structure can improve the hardness, aging resistance and other properties of the topcoat; second, the CF bond also has anti-fouling and high weather resistance effects; at the same time, it can improve the compatibility with functional resin I; third, the carbamate is a phenol-terminated structure, which is a closed polyurethane, which can be unblocked at about 200°C and used as a polyurethane curing agent; at the same time, the organic chain structure in the polyurethane curing agent can provide a certain toughening effect on the topcoat; fourth, the hard monomer acrylate structure can improve the hardness, gloss and other properties of the topcoat; fifth, the hyperbranched structure curing agent can effectively improve the cross-linking density of the topcoat, improve the compactness of the topcoat film, and thus improve the scratch resistance, corrosion resistance and weather resistance.

[0019] (4) The polyester topcoat for aluminum veneer for building curtain walls in the present invention is formulated such that polyester resin is compounded with functional resin I to improve chemical resistance; functional resin II and amino resin are used as curing agents to synergistically improve the crosslinking density, thereby improving the physical properties of the topcoat; in addition, inorganic pigments and fillers complement each other to further improve weather resistance, hardness, corrosion resistance, etc., which can solve existing problems and has important practical significance. Detailed implementation mode

[0020] The present invention will be described in detail below in conjunction with embodiments. It should be understood, however, that the following embodiments are merely illustrative examples of the implementation modes of the present invention and do not limit the scope of the present invention.

[0021] The object of the present invention is to develop a polyester topcoat for aluminum veneers of building curtain walls. The implementation idea is as follows: Considering that the polyester / amino topcoat has certain weather resistance, by compounding functional resins, while improving its chemical resistance (corrosion resistance), its weather resistance is further enhanced. To ensure the compatibility of the functional resin with the polyester resin, the functional resin preferably has a polyester structure or contains a large number of ester group structures. In addition, in view of the excellent properties of fluorocarbon resins, UV absorbers based on benzophenone, and the toughening effect of polyurethane curing agents, through molecular design, the C-F structure and UV absorbers based on benzophenone are placed in the polyester to form functional resin I; at the same time, self-made functional resin II (which is a hyperbranched structure) such as nano-silicon, C-F structure, and polyurethane curing agent is used to effectively promote the curing efficiency and improve the performance; by adding the above components to the polyester / amino system, problems such as poor chemical resistance and poor weather resistance can be solved, and at the same time, it also has excellent impact resistance, high hardness, and stain resistance. The theoretical basis for the implementation is as follows: For functional resin I, first, a structure based on 2,4,4'-trihydroxybenzophenone is obtained by coupling reaction with bromoethanol to obtain a fatty diol containing an o-hydroxybenzophenone structure; then it is obtained by esterification polycondensation reaction with polyfluorodiol, ethylene glycol, glycerol, and terephthalic acid; for functional resin II, first, 3 monomers are respectively prepared, namely monomers containing nano-silicon prepared by silane coupling agent, monomers containing fluorine prepared by nucleophilic addition reaction of perfluoroyl chloride and hydroxyl group, and monomers containing polyurethane curing agent prepared by nucleophilic addition of isocyanate alkene and phenol; then it is prepared by free radical polymerization of the above 3 monomers and acrylate monomers. The above two functional resins are added to the polyester / amino system through formula design and, in combination with pigments and fillers, can effectively solve the problems of poor chemical resistance and poor weather resistance of conventional polyester topcoats, and at the same time also have excellent impact resistance, high hardness, and stain resistance. The embodiments of the present invention are as follows: The embodiment of the present invention provides a polyester topcoat for aluminum veneers of building curtain walls, comprising the following raw materials in parts by weight: Saturated polyester resin 20 - 30 parts; Functional resin I 10 - 15 parts; Functional resin II 3.0 - 5.0 parts; Amino resin 5.0 - 9.0 parts; Pigment 15 - 25 parts; Filler 12 - 20 parts; Dispersant 0.2 - 0.5 part; Anti-settling agent 0.1 - 0.3 part; Defoamer: 0.1 - 0.2 parts; Leveling agent: 0.5 - 1.0 parts; S - 150 solvent: 10 - 15 parts; The saturated polyester resin, functional resin I, functional resin II, and amino resin are all calculated based on solid content; For the said functional resin I, its preparation method includes the following steps: S11, Add 2,4,4'-trihydroxybenzophenone derivative, bromoethanol, and potassium carbonate into N,N-dimethylformamide, heat to 110 - 130 °C and stir strongly for 1 - 3 h; after the reaction ends, cool to room temperature, concentrate the solution under vacuum, slowly add deionized water, stir for 0.5 h, then add ethyl acetate, stir for 0.5 h, let it stand, separate the liquid, take the organic phase, dry it with anhydrous sodium sulfate, filter, take the filtrate, distill it under reduced pressure, and dry it under vacuum at 60 °C for 6 h to obtain intermediate product 1I.

[0022] The dosage ratio of the 2,4,4'-trihydroxybenzophenone derivative, bromoethanol, potassium carbonate, N,N-dimethylformamide, deionized water, ethyl acetate, and anhydrous sodium sulfate is 0.1 mol: 0.2 mol: 0.2 mol: 300 mL: 300 mL: 500 mL: 5 g.

[0023] The 2,4,4'-trihydroxybenzophenone derivative is 2,4,4'-trihydroxybenzophenone or 2,2',4,4'-tetrahydroxybenzophenone.

[0024] S12, Under N2 protection, add intermediate product 1I, polyfluorodiol, ethylene glycol, glycerol, and catalyst into the reaction kettle, heat to 130 °C, stir, and keep warm for 0.5 h; then add terephthalic acid and xylene, stir and heat up to 160 - 180 °C to react for 4 - 6 h, continue to heat up to 190 - 210 °C to react until the water separation mass is constant; cool down and evacuate to remove the solvent, cool down to 80 - 90 °C, filter to obtain the target product, that is, functional resin I.

[0025] The total molar ratio of intermediate product 1I, polyfluorodiol, ethylene glycol, and glycerol to terephthalic acid is 1.1:1; and The molar ratio of intermediate product 1I, polyfluorodiol, ethylene glycol, and glycerol is 0.05 - 0.15: 0.60 - 0.80: 0.05 - 0.15: 0.10 - 0.20; The dosage of xylene is 5 wt% of the total mass of the reactants; The dosage of the catalyst is 0.1 wt% of the total mass of the reactants; The catalyst is dibutyltin oxide, zinc acetate, or tetrabutyl titanate; and preferably dibutyltin oxide.

[0026] The polyfluorodiol is 1H,1H,9H,9H-perfluoro-1,9-nonanediol or octafluoro-1,6-hexanediol.

[0027] The self-made functional resin I in the present invention is a linear polyester resin containing a hydroxyl structure, and also contains o-hydroxybenzophenone, fluorocarbon chain, etc. It can be effectively dispersed with the main resin, and at the same time can participate in the curing of functional resin II and amino resin, effectively improving the physical properties.

[0028] For the said functional resin II, its preparation method includes the following steps: S21, Add nano-silicon and deionized water A into absolute ethanol, after ultrasonic dispersion for 1 h, add glacial acetic acid to adjust the pH value to 3.5 - 4.5, add a silane coupling agent containing a carbon-carbon double bond, stir and ultrasonic for 0.5 h, then heat up to 40 - 60 °C and reflux for 2 - 4 h; after the reaction is completed, filter, take the insoluble matter, wash it with deionized water B, and vacuum dry it at 40 °C until constant weight to obtain intermediate product 2I.

[0029] The dosage ratio of the said nano-silicon, deionized water A, absolute ethanol, silane coupling agent containing a carbon-carbon double bond, and deionized water B is 1 g : 2 g : 18 g : 0.1 - 0.3 g : 30 g; The average particle size of the said nano-silicon is 100 nm, and it is purchased from Cabot Corporation.

[0030] The silane coupling agent containing a carbon-carbon double bond can be a vinyl silane coupling agent or an acryloxy silane coupling agent; The vinyl silane coupling agent can be silane coupling agent KH151, silane coupling agent KH171, silane coupling agent KH172, or silane coupling agent KH173, etc.; and preferably, silane coupling agent KH171.

[0031] The acryloxy silane coupling agent can be silane coupling agent KH570, silane coupling agent KH571, silane coupling agent KH670, etc.; and preferably, silane coupling agent KH570.

[0032] S22, Avoid light, dissolve the fluorinated acyl chloride in dichloromethane A and place it in a constant pressure dropping funnel, slowly drop it into dichloromethane B containing hydroxyalkene and triethylamine, use an ice bath, stir, after the dropping is completed, continue to stir at 0 - 5 °C for 8 - 14 h, after the reaction is completed; filter, take the filtrate, wash it 3 times with saturated sodium bicarbonate solution, then wash it 3 times with deionized water, separate the liquid, take the organic phase, dry it with anhydrous sodium sulfate, filter, distill the filtrate under reduced pressure, and vacuum dry it at 40 °C for 12 h to obtain intermediate product 2II.

[0033] The dosage ratio of the said fluorinated acyl chloride to hydroxyalkene is added according to the molar ratio of acyl chloride to hydroxyl group of 1:1; The dosage ratio of the fluorine-containing acyl chloride, dichloromethane A, triethylamine, dichloromethane B, saturated sodium bicarbonate solution, deionized water, and anhydrous sodium sulfate is 0.1 mol: 150 mL: 0.1 mol: 250 mL: 400 mL: 400 mL: 5 g.

[0034] The fluorine-containing acyl chloride is perfluorobutyryl chloride, perfluorooctanoyl chloride, or perfluorononanoyl chloride.

[0035] The hydroxy-alkenes are allyl hydroxy structure or hydroxyacrylate structure; The allyl hydroxy structure can be 4-penten-1-ol, 5-hexen-1-ol, 8-nonen-1-ol, 9-decen-1-ol, undecenol, etc.; and preferably 8-nonen-1-ol; The hydroxyacrylate structure can be 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl acrylate, etc.; and preferably 2-hydroxyethyl methacrylate.

[0036] S23, Add isocyano-alkenes, phenol, 2,6-di-tert-butyl-p-cresol, and dibutyltin dilaurate to N,N-dimethylformamide, stir, react at 60 - 80 °C for 6 - 10 h, then cool to room temperature, distill under reduced pressure, and dry in vacuum at 40 °C for 8 h to obtain intermediate 2III.

[0037] The dosage ratio of the isocyano-alkenes, phenol, and N,N-dimethylformamide is 0.1 mol: 0.1 mol: 150 mL.

[0038] The isocyano-alkenes are allyl isocyanate or acryloyloxy isocyanate; The allyl isocyanate can be 3-isocyanatopropene, etc.; The acryloyloxy isocyanate can be isocyanatoethyl methacrylate, etc.

[0039] The dosage of 2,6-di-tert-butyl-p-cresol is 0.5 wt% of the mass of the isocyano-alkenes.

[0040] The dosage of dibutyltin dilaurate is 0.5 wt% of the total mass of the reactants.

[0041] S24, Pass N2, add intermediate 2I, intermediate 2II, intermediate 2III, acrylate, and initiator to N,N-dimethylformamide, heat to 75 - 85 °C, stir for 6 - 10 h; cool to room temperature, filter to obtain the target product, i.e., functional resin II.

[0042] The dosage ratio of the intermediate 2I, intermediate 2II, intermediate 2III, and acrylate is 0.15 g: 0.60 - 0.80 g: 0.20 - 0.30 g: 0.10 - 0.20 g.

[0043] The dosage of the initiator is 1.0 wt% of the total mass of the reactants; and the initiator is AIBN.

[0044] The acrylate is a hard monomer acrylate; it can be methyl methacrylate, dicyclopentyl methacrylate, isobornyl methacrylate, etc.; and preferably isobornyl methacrylate.

[0045] The self-made functional resin II in the present invention has a hyperbranched structure containing nano-silicon, and the branched chains contain fluorocarbon chains, blocked polyurethane curing agent structures, and hard monomer structures, etc. It can be effectively miscible with functional resin II, and at the same time can participate in the curing with functional resin I and polyester resin; and the hyperbranched structure can effectively improve the curing efficiency and enhance the performance.

[0046] The hydroxyl value of the saturated polyester resin is a medium-hydroxyl polyester; it can be Miki polyester resin 3903A, Miki polyester resin 3905A, or Miki polyester resin 3910, etc.; and in the following examples of the present invention, the saturated polyester resin is Miki polyester resin 3910.

[0047] The amino resin is a mixture of fully methylated amino resin and partially methylated amino resin; The fully methylated amino resin can be Cytec amino resin 303, Miki amino resin 5747, Miki amino resin 5847, etc.; and preferably Cytec amino resin 303; The partially methylated amino resin can be Cytec amino resin 325, Miki amino resin 5717, etc.; and preferably Cytec amino resin 325; In the present invention, the amino resin is Cytec amino resin 303 and Cytec amino resin 325 added in a mass ratio of 3.0:1.

[0048] The pigment is an inorganic pigment; it can be one or several of rutile titanium dioxide, carbon black, or ceramic pigment, etc.; and in the following examples of the present invention, the pigment is a mixture of rutile titanium dioxide and carbon black in a mass ratio of 5:1.

[0049] The filler can be ultrafine barium sulfate, ultrafine mica powder, kaolin, talc powder, etc.; and in the following examples of the present invention, the fillers are all a mixture of ultrafine mica powder and kaolin in a mass ratio of 2.5:1.

[0050] The dispersant is BYK-110.

[0051] The anti-settling agent is Aerosil 200 fumed silica.

[0052] The defoaming agent is BYK-066N.

[0053] The leveling agent is EFKA 3777N.

[0054] Another object of the embodiments of the present invention is to provide a preparation method of a polyester topcoat for aluminum single panels of building curtain walls, including the following steps: S31, paint formulation, that is Take 40% of the formula amount of saturated polyester resin, and sequentially add the formula amount of S-150 aromatic hydrocarbon solvent, the formula amount of functional resin I, the formula amount of dispersant, the formula amount of anti-settling agent, the formula amount of defoaming agent, the formula amount of pigment, and the formula amount of filler at a rotation speed of 500 - 700 r / min, and then stir at a high speed of 1800 - 2200 r / min for 20 - 30 min to obtain premixed liquid I; S32, grinding, that is Transfer premixed liquid I to a grinding machine and grind it until a mixed liquid II with a solid particle fineness ≤ 20 μm is obtained; S33, add the remaining raw materials and dilute, that is Stir the mixed liquid II at a rotation speed of 600 r / min, and sequentially add the remaining saturated polyester resin, the formula amount of amino resin, the formula amount of functional resin II, and the formula amount of leveling agent; adjust the viscosity of the mixed liquid to 100 - 120 s (Ford cup 4# cup at 25°C) with an appropriate amount of ethylene glycol monobutyl ether, and continue to stir at a low speed of 300 - 400 r / min for 8 - 12 min to obtain mixed liquid III; S34, filtration and collection, that is Filter the mixed liquid III with a filter bag with a pore size of 50 μm, and the filtrate is the polyester topcoat for aluminum single panels of building curtain walls.

[0055] Another object of the embodiments of the present invention is to provide an application of the polyester topcoat for aluminum single panels of building curtain walls in coiled aluminum curtain walls.

[0056] To further understand the present invention, the following is a detailed description of a polyester topcoat for aluminum single panels of building curtain walls provided by the present invention in conjunction with embodiments, and the protection scope of the present invention is not limited by the following embodiments.

[0057] Example 1 This example provides a polyester topcoat for aluminum single panels of building curtain walls, including the following raw materials in parts by weight: Saturated polyester resin 25 parts; Functional resin I 13 parts; Functional resin II 4.0 parts; 7.0 parts of amino resin; 20 parts of pigment; 16 parts of filler; 0.4 part of dispersant; 0.2 part of anti-settling agent; 0.15 part of defoaming agent; 0.8 part of leveling agent; 13 parts of S-150 solvent; The saturated polyester resin, functional resin I, functional resin II, and amino resin are all calculated based on solid content; For the functional resin I, its preparation method includes the following steps: S11, Add 2,4,4'-trihydroxybenzophenone, bromoethanol, and potassium carbonate to N,N-dimethylformamide, heat to 120 °C and stir strongly for 2 h; after the reaction is completed, cool to room temperature, vacuum concentrate the solution, slowly add deionized water, stir for 0.5 h, then add ethyl acetate, stir for 0.5 h, let stand, separate the liquid, take the organic phase, dry it with anhydrous sodium sulfate, filter, take the filtrate, distill it under reduced pressure, and vacuum dry it at 60 °C for 6 h to obtain intermediate product 1I.

[0058] The dosage ratio of the 2,4,4'-trihydroxybenzophenone derivative, bromoethanol, potassium carbonate, N,N-dimethylformamide, deionized water, ethyl acetate, and anhydrous sodium sulfate is 0.1 mol: 0.2 mol: 0.2 mol: 300 mL: 300 mL: 500 mL: 5 g.

[0059] Its infrared data is as follows: 3488 cm -1 : -OH exists; 3021 cm -1 , 1582 cm -1 , 1480 cm -1 : Benzene ring exists; 674 cm -1 : -C-Br does not exist.

[0060] S12, Under N2 protection, add intermediate product 1I, 1H,1H,9H,9H-perfluoro-1,9-nonanediol, ethylene glycol, glycerol, and dibutyltin oxide to the reaction kettle, heat up to 130 °C, stir, and keep warm for 0.5 h; then add terephthalic acid and xylene, stir and heat up to 160 °C and keep warm for 2 h, heat up to 170 °C and keep warm for 1 h, heat up to 180 °C and keep warm for 2 h, continue to heat up to 190 °C and keep warm for 0.5 h, keep warm at 200 °C for 0.5 h, and react at 210 °C until the water separation mass is constant; cool down and evacuate to remove the solvent, cool down to 95 °C, and filter to obtain the target product, that is, functional resin I.

[0061] The molar ratio of the total number of moles of the intermediate 1I, 1H,1H,9H,9H-perfluorononane-1,9-diol, ethylene glycol, and glycerol to terephthalic acid is 1.1:1; and The molar ratio of the intermediate 1I, 1H,1H,9H,9H-perfluorononane-1,9-diol, ethylene glycol, and glycerol is 0.10:0.70:0.15:0.15; The dosage of xylene is 5 wt% of the total mass of the reactants; The dosage of dibutyltin oxide is 0.1 wt% of the total mass of the reactants.

[0062] Its infrared data is as follows: 3485 cm -1 : -OH exists and weakens; 3021 cm -1 、1582 cm -1 、1480 cm -1 : Benzene ring exists; 1756 cm -1 : -C=O (carboxyl group) does not exist; 1735 cm -1 : -C=O (ester group) exists; 1312 cm -1 : -C-F exists.

[0063] For the functional resin II, its preparation method includes the following steps: S21, Add nano-silicon and deionized water A to absolute ethanol, after ultrasonic dispersion for 1 h, add glacial acetic acid to adjust the pH value to 4.0, add silane coupling agent KH570, stir and ultrasonic for 0.5 h, then heat up to 50 °C and reflux for 3 h; after the reaction is completed, filter, take the insoluble matter, wash it with deionized water B, and vacuum dry it at 40 °C until constant weight to obtain the intermediate 2I.

[0064] The dosage ratio of the nano-silicon, deionized water A, absolute ethanol, silane coupling agent KH570, and deionized water B is 1 g:2 g:18 g:0.2 g:30 g.

[0065] Its infrared data is as follows: 3368 cm -1 : -OH exists and weakens; 1735 cm -1 : -C=O (ester group) exists; 1605 cm -1 、811 cm -1 : -C=C- exists; 1109 cm -1 、791 cm -1 : -Si-O- exists.

[0066] S22. Protect from light. Dissolve perfluorooctanoyl chloride in dichloromethane A and place it in a constant pressure dropping funnel. Slowly add it dropwise to the dichloromethane B solution of 2-hydroxyethyl methacrylate and triethylamine. Keep it in an ice bath and stir. After the dropping is completed, continue to stir at 0 °C for 10 h. After the reaction is completed, filter, take the filtrate, wash it 3 times with saturated sodium bicarbonate solution, then wash it 3 times with deionized water, separate the liquid, take the organic phase, dry it with anhydrous sodium sulfate, filter, and distill the filtrate under reduced pressure. After vacuum drying at 40 °C for 12 h, the intermediate 2II is obtained.

[0067] The dosage ratio of perfluorooctanoyl chloride to 2-hydroxyethyl methacrylate is added according to the molar ratio of acyl chloride to hydroxyl group of 1:1. The dosage ratio of perfluorooctanoyl chloride, dichloromethane A, triethylamine, dichloromethane B, saturated sodium bicarbonate solution, deionized water, and anhydrous sodium sulfate is 0.1 mol: 150 mL: 0.1 mol: 250 mL: 400 mL: 400 mL: 5 g.

[0068] Its infrared data is as follows: 3491 cm -1 : -OH does not exist; 1778 cm -1 : Cl-C=O does not exist; 1735 cm -1 : -C=O (ester group) exists and is enhanced; 1606 cm -1 、811 cm -1 : -C=C- exists; 1310 cm -1 : -C-F exists; 714 cm -1 : -C-Cl does not exist.

[0069] S23. Add isocyanatoethyl methacrylate, phenol, 2,6-di-tert-butyl-p-cresol, and dibutyltin dilaurate to N,N-dimethylformamide, stir, react at 70 °C for 8.5 h, then cool to room temperature, distill under reduced pressure, and vacuum dry at 40 °C for 8 h to obtain the intermediate 2III.

[0070] The dosage ratio of isocyanatoethyl methacrylate, phenol, and N,N-dimethylformamide is 0.1 mol: 0.1 mol: 150 mL.

[0071] The dosage of 2,6-di-tert-butyl-p-cresol is 0.5 wt% of the mass of isocyanatoethyl methacrylate.

[0072] The dosage of dibutyltin dilaurate is 0.5 wt% of the total mass of the reactants.

[0073] Its infrared data is as follows: 3454 cm -1 : -OH does not exist; 3318 cm -1 : -NH- sharp peak exists; 3021 cm -1 、1582 cm-1 、1480 cm -1 : The benzene ring exists; 2270 cm -1 : -NCO does not exist; 1735 cm -1 : -C=O (ester group) exists; 1711 cm -1 : -C=O (urethane) exists; 1606 cm -1 、811 cm -1 : -C=C- exists; 1551 cm -1 : -NH- (amide) exists.

[0074] S24. Pass N2, add intermediate 2I, intermediate 2II, intermediate 2III, isobornyl methacrylate, and initiator AIBN into N,N-dimethylformamide, heat up to 80 °C, stir for 7.5 h; cool to room temperature, filter to obtain the target product, namely functional resin II.

[0075] The dosage ratio of the intermediate 2I, intermediate 2II, intermediate 2III, and isobornyl methacrylate is 0.15 g: 0.70 g: 0.25 g: 0.15 g.

[0076] The dosage of the initiator AIBN is 1.0 wt% of the total mass of the reactants.

[0077] Its infrared data is as follows: 3368 cm -1 : -OH exists; 3318 cm -1 : -NH- peak exists; 3021 cm -1 、1582 cm -1 、1480 cm -1 : The benzene ring exists; 1735 cm -1 : -C=O (ester group) exists and is enhanced; 1711 cm -1 : -C=O (urethane) exists; 1551 cm -1 : -NH- (amide) exists; 1605 cm -1 、811 cm -1 : -C=C- does not exist; 1310 cm -1 : -C-F exists; 1109 cm -1 、791 cm -1 : -Si-O- exists.

[0078] Another object of the embodiments of the present invention is to provide a preparation method of a polyester topcoat for aluminum single panels of building curtain walls, including the following steps: S31. Prepare the paint, that is Take 40% of the formulation amount of saturated polyester resin, and successively add the formulation amount of S-150 aromatic hydrocarbon solvent, the formulation amount of functional resin I, the formulation amount of dispersant, the formulation amount of anti-settling agent, the formulation amount of defoaming agent, the formulation amount of pigment, and the formulation amount of filler at a rotation speed of 600 r / min. Then, stir at a high speed of 2000 r / min for 25 min to obtain premixed liquid I; S32, grinding, that is Transfer premixed liquid I to a grinding machine and grind it until a mixed liquid II with a solid particle fineness ≤ 20 μm is obtained; S33, adding the remaining raw materials and diluting, that is Stir the mixed liquid II at a rotation speed of 600 r / min, and successively add the remaining saturated polyester resin, the formulation amount of amino resin, the formulation amount of functional resin II, and the formulation amount of leveling agent; adjust the viscosity of the mixed liquid to 110 s (Ford Cup No. 4 cup at 25 °C) with an appropriate amount of ethylene glycol monobutyl ether, and continue to stir at a low speed of 350 r / min for 10 min to obtain mixed liquid III; S34, filtering and collecting, that is Filter the mixed liquid III with a filter bag with a pore size of 50 μm, and the filtrate is the polyester topcoat for building curtain wall aluminum single panels.

[0079] Another object of the embodiment of the present invention is to provide an application of the polyester topcoat for building curtain wall aluminum single panels in a coil curtain wall.

[0080] Example 2 This embodiment provides a polyester topcoat for building curtain wall aluminum single panels, which comprises the following raw materials in parts by weight: Saturated polyester resin: 20 parts; Functional resin I: 10 parts; Functional resin II: 3.0 parts; Amino resin: 5.6 parts; Pigment: 15 parts; Filler: 12 parts; Dispersant: 0.2 part; Anti-settling agent: 0.1 part; Defoaming agent: 0.1 part; Leveling agent: 0.5 part; S-150 solvent: 10 parts; The saturated polyester resin, functional resin I, functional resin II, and amino resin are all calculated based on solid content; For the functional resin I, its preparation method comprises the following steps: S11. Add 2,4,4'-trihydroxybenzophenone, bromoethanol, and potassium carbonate into N,N-dimethylformamide, heat to 130 °C and stir vigorously for 1 h. After the reaction is completed, cool to room temperature, concentrate the solution under vacuum, slowly add deionized water, stir for 0.5 h, then add ethyl acetate, stir for 0.5 h, let it stand, separate the liquid, take the organic phase, dry it with anhydrous sodium sulfate, filter, take the filtrate, distill it under reduced pressure, and dry it under vacuum at 60 °C for 6 h to obtain intermediate 1I.

[0081] The dosage ratio of the 2,4,4'-trihydroxybenzophenone derivative, bromoethanol, potassium carbonate, N,N-dimethylformamide, deionized water, ethyl acetate, and anhydrous sodium sulfate is 0.1 mol: 0.2 mol: 0.2 mol: 300 mL: 300 mL: 500 mL: 5 g.

[0082] S12. Under N2 protection, add intermediate 1I, 1H,1H,9H,9H-perfluoro-1,9-nonanediol, ethylene glycol, glycerol, and dibutyltin oxide into a reaction kettle, heat up to 130 °C, stir, and keep warm for 0.5 h. Then add terephthalic acid and xylene, stir and heat up to 160 °C and keep warm for 1 h, heat up to 170 °C and keep warm for 1 h, heat up to 180 °C and keep warm for 2 h, continue to heat up to 190 °C and keep warm for 0.5 h, keep warm at 200 °C for 0.5 h, and react at 210 °C until the mass of the separated water is constant. Cool down and evacuate to remove the solvent, cool down to 90 °C, and filter to obtain the target product, i.e., functional resin I.

[0083] The molar ratio of the total moles of intermediate 1I, 1H,1H,9H,9H-perfluoro-1,9-nonanediol, ethylene glycol, and glycerol to terephthalic acid is 1.1:1; and The molar ratio of intermediate 1I, 1H,1H,9H,9H-perfluoro-1,9-nonanediol, ethylene glycol, and glycerol is 0.10:0.70:0.15:0.15; The dosage of xylene is 5 wt% of the total mass of the reactants; The dosage of dibutyltin oxide is 0.1 wt% of the total mass of the reactants.

[0084] For the preparation method of the functional resin II, it includes the following steps: S21. Add nano-silicon and deionized water A into absolute ethanol, disperse it by ultrasonic wave for 1 h, then add glacial acetic acid to adjust the pH value to 3.5, add silane coupling agent KH570, stir and ultrasonic wave for 0.5 h, then heat up to 60 °C and reflux for 2 h. After the reaction is completed, filter, take the insoluble matter, wash it with deionized water B, and dry it under vacuum at 40 °C until the weight is constant to obtain intermediate 2I.

[0085] The dosage ratio of the nano-silicon, deionized water A, absolute ethanol, silane coupling agent KH570, and deionized water B is 1 g: 2 g: 18 g: 0.1 g: 30 g.

[0086] S22. Under light avoidance conditions, dissolve perfluorooctanoyl chloride in dichloromethane A and place it in a constant pressure dropping funnel. Slowly add it dropwise to the dichloromethane B solution of 2-hydroxyethyl methacrylate and triethylamine. Keep it in an ice bath and stir. After the dropping is completed, continue to stir at 0 °C for 14 h. After the reaction is completed, filter, take the filtrate, wash it 3 times with saturated sodium bicarbonate solution, then wash it 3 times with deionized water, separate the liquid, take the organic phase, dry it with anhydrous sodium sulfate, filter, and distill the filtrate under reduced pressure. After vacuum drying at 40 °C for 12 h, the intermediate 2II is obtained.

[0087] The dosage ratio of the perfluorooctanoyl chloride to 2-hydroxyethyl methacrylate is added according to the molar ratio of acyl chloride to hydroxyl group of 1:1. The dosage ratio of the perfluorooctanoyl chloride, dichloromethane A, triethylamine, dichloromethane B, saturated sodium bicarbonate solution, deionized water, and anhydrous sodium sulfate is 0.1 mol: 150 mL: 0.1 mol: 250 mL: 400 mL: 400 mL: 5 g.

[0088] S23. Add isocyanatoethyl methacrylate, phenol, 2,6-di-tert-butyl-p-cresol, and dibutyltin dilaurate to N,N-dimethylformamide, stir, react at 60 °C for 10 h, then cool to room temperature, distill under reduced pressure, and after vacuum drying at 40 °C for 8 h, the intermediate 2III is obtained.

[0089] The dosage ratio of the isocyanatoethyl methacrylate, phenol, and N,N-dimethylformamide is 0.1 mol: 0.1 mol: 150 mL.

[0090] The dosage of 2,6-di-tert-butyl-p-cresol is 0.5 wt% of the mass of isocyanatoethyl methacrylate.

[0091] The dosage of dibutyltin dilaurate is 0.5 wt% of the total mass of the reactants.

[0092] S24. Pass N2. Add the intermediate 2I, intermediate 2II, intermediate 2III, isobornyl methacrylate, and initiator AIBN to N,N-dimethylformamide, heat up to 75 °C, and stir for 10 h; then cool to room temperature and filter to obtain the target product, namely the functional resin II.

[0093] The dosage ratio of the intermediate 2I, intermediate 2II, intermediate 2III, and isobornyl methacrylate is 0.15 g: 0.70 g: 0.25 g: 0.15 g.

[0094] The dosage of the initiator AIBN is 1.0 wt% of the total mass of the reactants.

[0095] Another object of the embodiments of the present invention is to provide a preparation method of a polyester topcoat for aluminum veneers of building curtain walls, comprising the following steps: S31, paint formulation, that is Take 40% of the formulated amount of saturated polyester resin, and successively add the formulated amount of S-150 aromatic hydrocarbon solvent, the formulated amount of functional resin I, the formulated amount of dispersant, the formulated amount of anti-settling agent, the formulated amount of defoaming agent, the formulated amount of pigment, and the formulated amount of filler at a rotation speed of 500 r / min, and then stir at a high speed of 1800 r / min for 30 min to obtain premixed liquid I; S32, grinding, that is Transfer premixed liquid I to a grinding machine and grind it until a mixed liquid II with a solid particle fineness ≤ 20 μm is obtained; S33, add the remaining raw materials and dilute, that is Stir the mixed liquid II at a rotation speed of 600 r / min, and successively add the remaining saturated polyester resin, the formulated amount of amino resin, the formulated amount of functional resin II, and the formulated amount of leveling agent; adjust the viscosity of the mixed liquid to 100 s (Ford cup No. 4 cup at 25 °C) with an appropriate amount of ethylene glycol monobutyl ether, and continue to stir at a low speed of 300 r / min for 12 min to obtain mixed liquid III; S34, filtration and collection, that is Filter the mixed liquid III with a filter bag with a pore size of 50 μm, and the filtrate is the polyester topcoat for aluminum veneers of building curtain walls.

[0096] Another object of the embodiments of the present invention is to provide an application of the polyester topcoat for aluminum veneers of building curtain walls in coiled aluminum curtain walls.

[0097] Example 3 This example provides a polyester topcoat for aluminum veneers of building curtain walls, comprising the following raw materials in parts by weight: Saturated polyester resin 30 parts; Functional resin I 15 parts; Functional resin II 5.0 parts; Amino resin 8.4 parts; Pigment 25 parts; Filler 20 parts; Dispersant 0.5 part; Anti-settling agent 0.3 part; Defoaming agent 0.2 part; Leveling agent 1.0 part; S-150 solvent 15 parts; The saturated polyester resin, functional resin I, functional resin II, and amino resin are all based on solid content; For the functional resin I, its preparation method includes the following steps: S11: Add 2,4,4'-trihydroxybenzophenone, bromoethanol, and potassium carbonate into N,N-dimethylformamide, heat to 110 °C and stir vigorously for 3 h; after the reaction ends, cool to room temperature, vacuum-concentrate the solution, slowly add deionized water, stir for 0.5 h, then add ethyl acetate, stir for 0.5 h, let stand, separate the liquid, take the organic phase, dry it with anhydrous sodium sulfate, filter, take the filtrate, perform vacuum distillation, and vacuum-dry at 60 °C for 6 h to obtain intermediate product 1I.

[0098] The dosage ratio of the 2,4,4'-trihydroxybenzophenone derivative, bromoethanol, potassium carbonate, N,N-dimethylformamide, deionized water, ethyl acetate, and anhydrous sodium sulfate is 0.1 mol: 0.2 mol: 0.2 mol: 300 mL: 300 mL: 500 mL: 5 g.

[0099] S12: Under N2 protection, add intermediate product 1I, 1H,1H,9H,9H-perfluoro-1,9-nonanediol, ethylene glycol, glycerol, and dibutyltin oxide into the reaction kettle, heat to 130 °C, stir, and keep warm for 0.5 h; then add terephthalic acid and xylene, stir and heat to 160 °C and keep warm for 2 h, then heat to 170 °C and keep warm for 2 h, then heat to 180 °C and keep warm for 2 h, continue to heat to 190 °C and keep warm for 0.5 h, keep warm at 200 °C for 0.5 h, and react at 210 °C until the water separation mass is constant; cool down and evacuate to remove the solvent, cool to 80 °C, and filter to obtain the target product, i.e., functional resin I.

[0100] The molar ratio of the total amount of intermediate product 1I, 1H,1H,9H,9H-perfluoro-1,9-nonanediol, ethylene glycol, and glycerol to terephthalic acid is 1.1:1; and The molar ratio of intermediate product 1I, 1H,1H,9H,9H-perfluoro-1,9-nonanediol, ethylene glycol, and glycerol is 0.10:0.70:0.15:0.15; The dosage of xylene is 5 wt% of the total mass of the reactants; The dosage of dibutyltin oxide is 0.1 wt% of the total mass of the reactants.

[0101] For the functional resin II, its preparation method includes the following steps: S21. Add nano-silicon and deionized water A to absolute ethanol. After ultrasonic dispersion for 1 h, add glacial acetic acid to adjust the pH value to 4.5. Then add silane coupling agent KH570, stir and ultrasonicate for 0.5 h, and then heat up to 40 °C for reflux for 4 h. After the reaction is completed, filter, take the insoluble matter, wash it with deionized water B, and vacuum dry it at 40 °C until constant weight to obtain intermediate product 2I.

[0102] The dosage ratio of the nano-silicon, deionized water A, absolute ethanol, silane coupling agent KH570, and deionized water B is 1 g: 2 g: 18 g: 0.3 g: 30 g.

[0103] S22. Under light avoidance, dissolve perfluorooctanoyl chloride in dichloromethane A and place it in a constant pressure dropping funnel. Slowly add it dropwise to the dichloromethane B containing 2-hydroxyethyl methacrylate and triethylamine. Keep it in an ice bath and stir. After the dropping is completed, continue to stir at 5 °C for 8 h. After the reaction is completed, filter, take the filtrate, wash it 3 times with saturated sodium bicarbonate solution, then wash it 3 times with deionized water, separate the layers, take the organic phase, dry it with anhydrous sodium sulfate, filter, and distill the filtrate under reduced pressure. After vacuum drying at 40 °C for 12 h, obtain intermediate product 2II.

[0104] The dosage ratio of the perfluorooctanoyl chloride to 2-hydroxyethyl methacrylate is added according to the molar ratio of acyl chloride to hydroxyl group of 1:1. The dosage ratio of the perfluorooctanoyl chloride, dichloromethane A, triethylamine, dichloromethane B, saturated sodium bicarbonate solution, deionized water, and anhydrous sodium sulfate is 0.1 mol: 150 mL: 0.1 mol: 250 mL: 400 mL: 400 mL: 5 g.

[0105] S23. Add isocyanatoethyl methacrylate, phenol, 2,6-di-tert-butyl-p-cresol, and dibutyltin dilaurate to N,N-dimethylformamide, stir, react at 80 °C for 6 h, then cool to room temperature, distill under reduced pressure, and vacuum dry at 40 °C for 8 h to obtain intermediate product 2III.

[0106] The dosage ratio of the isocyanatoethyl methacrylate, phenol, and N,N-dimethylformamide is 0.1 mol: 0.1 mol: 150 mL.

[0107] The dosage of 2,6-di-tert-butyl-p-cresol is 0.5 wt% of the mass of isocyanatoethyl methacrylate.

[0108] The dosage of dibutyltin dilaurate is 0.5 wt% of the total mass of the reactants.

[0109] S24. Through N2, add intermediate product 2I, intermediate product 2II, intermediate product 2III, isobornyl methacrylate, and initiator AIBN into N,N-dimethylformamide. Heat the mixture to 85°C and stir for 6 h. Cool to room temperature and filter to obtain the target product, i.e., functional resin II.

[0110] The dosage ratio of the intermediate product 2I, intermediate product 2II, intermediate product 2III, and isobornyl methacrylate is 0.15 g:0.70 g:0.25 g:0.15 g.

[0111] The dosage of the initiator AIBN is 1.0 wt% of the total mass of the reactants.

[0112] Another object of the embodiments of the present invention is to provide a preparation method of a polyester topcoat for architectural curtain wall aluminum single panels, including the following steps: S31. Prepare the paint, i.e., Take 40% of the formulated amount of saturated polyester resin, and sequentially add the formulated amount of S-150 aromatic hydrocarbon solvent, the formulated amount of functional resin I, the formulated amount of dispersant, the formulated amount of anti-settling agent, the formulated amount of defoaming agent, the formulated amount of pigment, and the formulated amount of filler at a rotation speed of 700 r / min. Then, stir at a high speed of 2200 r / min for 20 min to obtain a premixed liquid I. S32. Grind the slurry, i.e., Transfer the premixed liquid I to a grinder and grind it until a mixed liquid II with a solid particle fineness of ≤20 μm is obtained. S33. Add the remaining raw materials and dilute, i.e., Stir the mixed liquid II at a rotation speed of 600 r / min, and sequentially add the remaining saturated polyester resin, the formulated amount of amino resin, the formulated amount of functional resin II, and the formulated amount of leveling agent. Adjust the viscosity of the mixed liquid to 120 s (Ford cup No. 4 cup at 25°C) with an appropriate amount of ethylene glycol monobutyl ether, and continue to stir at a low speed of 400 r / min for 8 min to obtain a mixed liquid III. S34. Filter and collect, i.e., Filter the mixed liquid III with a filter bag having a pore size of 50 μm, and the filtrate is the polyester topcoat for architectural curtain wall aluminum single panels.

[0113] Another object of the embodiments of the present invention is to provide an application of the polyester topcoat for architectural curtain wall aluminum single panels in coiled aluminum curtain walls.

[0114] Example 4 Other conditions are the same as those in Example 1, except that: This example provides a polyester topcoat for architectural curtain wall aluminum single panels, including the following raw materials in parts by weight: Saturated polyester resin 25 parts; 13 parts of functional resin I; 4.0 parts of functional resin II; 7.0 parts of amino resin; 23 parts of pigment; 18.5 parts of filler; 0.45 part of dispersant; 0.25 part of anti-settling agent; 0.2 part of defoaming agent; 1.0 part of leveling agent; 15 parts of S-150 solvent; The saturated polyester resin, functional resin I, functional resin II, and amino resin are all based on solid content.

[0115] Example 5 Others are the same as in Example 1, except that: This example provides a polyester topcoat for aluminum single panels of building curtain walls, comprising the following raw materials in parts by weight: 25 parts of saturated polyester resin; 13 parts of functional resin I; 4.0 parts of functional resin II; 7.0 parts of amino resin; 18 parts of pigment; 14 parts of filler; 0.3 part of dispersant; 0.15 part of anti-settling agent; 0.1 part of defoaming agent; 0.5 part of leveling agent; 10 parts of S-150 solvent; The saturated polyester resin, functional resin I, functional resin II, and amino resin are all based on solid content.

[0116] Example 6 Others are the same as in Example 1, except that: This example provides a polyester topcoat for aluminum single panels of building curtain walls, comprising the following raw materials in parts by weight: 25 parts of saturated polyester resin; 13 parts of functional resin I; 4.0 parts of functional resin II; 8.3 parts of amino resin; 20 parts of pigment; 16 parts of filler; 0.4 part of dispersant; 0.2 part of anti-settling agent; 0.15 part of defoaming agent; 0.8 part of leveling agent; 13 parts of S-150 solvent; The saturated polyester resin, functional resin I, functional resin II, and amino resin are all based on solid content.

[0117] Example 7 Others are the same as in Example 1, except that: This example provides a polyester topcoat for aluminum single panels of building curtain walls, comprising the following raw materials in parts by weight: 25 parts of saturated polyester resin; 13 parts of functional resin I; 4.0 parts of functional resin II; 6.25 parts of amino resin; 20 parts of pigment; 16 parts of filler; 0.4 part of dispersant; 0.2 part of anti-settling agent; 0.15 part of defoaming agent; 0.8 part of leveling agent; 13 parts of S-150 solvent; The saturated polyester resin, functional resin I, functional resin II, and amino resin are all based on solid content.

[0118] Example 8 Others are the same as in Example 1, except that: In a polyester topcoat formulation for aluminum single panels of building curtain walls, For the functional resin I, its preparation method, In S11, replace the 2,4,4'-trihydroxybenzophenone with 2,2',4,4'-tetrahydroxybenzophenone; and In S12, replace the 1H,1H,9H,9H-perfluoro-1,9-nonanediol with octafluoro-1,6-hexanediol; and the molar ratio of the intermediate 1I, octafluoro-1,6-hexanediol, ethylene glycol, and glycerol is 0.10:0.80:0.05:0.15.

[0119] Example 9 Others are the same as in Example 1, except that: In a polyester topcoat formulation for aluminum single panels of building curtain walls, For the functional resin I, its preparation method, in S12, The molar ratio of the intermediate 1I, 1H,1H,9H,9H-perfluoro-1,9-nonanediol, ethylene glycol, and glycerol is 0.15:0.60:0.15:0.20.

[0120] Example 10 Others are the same as in Example 1, except that: In a polyester topcoat formulation for aluminum single panels of building curtain walls, For the functional resin I, in its preparation method, in S12, The molar ratio of the intermediate 1I, 1H,1H,9H,9H-perfluoro-1,9-nonanediol, ethylene glycol, and glycerol is 0.05:0.80:0.15:0.10.

[0121] Example 11 Others are the same as in Example 1, except that: In a polyester topcoat formulation for aluminum single panels of building curtain walls, For the functional resin II, its preparation method, In S22, replace the perfluorooctanoyl chloride with perfluorobutanoyl chloride; and In S24, the dosage ratio of the intermediate 2I, intermediate 2II, intermediate 2III, and isobornyl methacrylate is 0.15 g:0.80 g:0.20 g:0.10 g.

[0122] Example 12 Others are the same as in Example 1, except that: In a polyester topcoat formulation for aluminum single panels of building curtain walls, For the functional resin II, its preparation method, In S22, replace the perfluorooctanoyl chloride with perfluorononanoyl chloride; and In S24, the dosage ratio of the intermediate 2I, intermediate 2II, intermediate 2III, and isobornyl methacrylate is 0.15 g:0.60 g:0.30 g:0.20 g.

[0123] Example 13 Others are the same as in Example 1, except that: In a polyester topcoat formulation for aluminum single panels of building curtain walls, For the functional resin II, its preparation method, in S24, The dosage ratio of the intermediate 2I, intermediate 2II, intermediate 2III, and isobornyl methacrylate is 0.15 g:0.60 g:0.25 g:0.15 g.

[0124] Example 14 Others are the same as in Example 1, except that: In a polyester topcoat formulation for aluminum single panels of building curtain walls, For the functional resin II, its preparation method, in S24, The dosage ratio of the intermediate product 2I, intermediate product 2II, intermediate product 2III, and isobornyl methacrylate is 0.15 g: 0.80 g: 0.25 g: 0.15 g.

[0125] Example 15 The others are the same as in Example 1, except that: In a polyester topcoat formulation for aluminum single panels of building curtain walls, For the functional resin II, its preparation method, In S21, replace the silane coupling agent KH570 with the silane coupling agent KH171; In S22, replace the hydroxyethyl methacrylate with 8-nonen-1-ol; and In S23, replace the isocyanatoethyl methacrylate with 3-isocyanatopropene.

[0126] The following comparative examples are all compared with Specific Example 1: Comparative Example 1 The others are the same as in Example 1, except that: In a polyester topcoat formulation for aluminum single panels of building curtain walls, Replace the functional resin I with a saturated polyester resin; and Replace the functional resin II with an amino resin.

[0127] Comparative Example 2 The others are the same as in Example 1, except that: In a polyester topcoat formulation for aluminum single panels of building curtain walls, Replace the functional resin I with a saturated polyester resin.

[0128] Comparative Example 3 The others are the same as in Example 1, except that: In a polyester topcoat formulation for aluminum single panels of building curtain walls, Replace the functional resin II with an amino resin.

[0129] Comparative Example 4 The others are the same as in Example 1, except that: A polyester topcoat for aluminum single panels of building curtain walls, comprising the following raw materials in parts by weight: Saturated polyester resin 25 parts; Functional resin I 13 parts; Functional resin II 4.0 parts; Amino resin 7.0 parts; Pigment 25.5 parts; Filler 21 parts; Dispersant 0.4 part; Anti-settling agent: 0.2 part; Defoaming agent: 0.15 part; Leveling agent: 0.8 part; S-150 solvent: 13 parts; The saturated polyester resin, functional resin I, functional resin II, and amino resin are all calculated based on solid content.

[0130] Implement Comparative Example 5 Others are the same as in Example 1, the difference is: A polyester topcoat for aluminum single panels of building curtain walls, comprising the following raw materials in parts by weight: Saturated polyester resin: 25 parts; Functional resin I: 13 parts; Functional resin II: 4.0 parts; Amino resin: 7.0 parts; Pigment: 13 parts; Filler: 11.5 parts; Dispersant: 0.4 part; Anti-settling agent: 0.2 part; Defoaming agent: 0.15 part; Leveling agent: 0.8 part; S-150 solvent: 13 parts; The saturated polyester resin, functional resin I, functional resin II, and amino resin are all calculated based on solid content.

[0131] Implement Comparative Example 6 Others are the same as in Example 1, the difference is: A polyester topcoat for aluminum single panels of building curtain walls, comprising the following raw materials in parts by weight: Saturated polyester resin: 25 parts; Functional resin I: 13 parts; Functional resin II: 4.0 parts; Amino resin: 10.0 parts; Pigment: 20 parts; Filler: 16 parts; Dispersant: 0.4 part; Anti-settling agent: 0.2 part; Defoaming agent: 0.15 part; Leveling agent: 0.8 part; S-150 solvent: 13 parts; The saturated polyester resin, functional resin I, functional resin II, and amino resin are all calculated based on solid content.

[0132] Implement Comparative Example 7 Others are the same as in Example 1, the difference is: A polyester topcoat for aluminum single panels of building curtain walls, comprising the following raw materials in parts by weight: 25 parts of saturated polyester resin; 13 parts of functional resin I; 4.0 parts of functional resin II; 5.5 parts of amino resin; 20 parts of pigment; 16 parts of filler; 0.4 part of dispersant; 0.2 part of anti-settling agent; 0.15 part of defoaming agent; 0.8 part of leveling agent; 13 parts of S-150 solvent; The saturated polyester resin, functional resin I, functional resin II, and amino resin are all calculated based on solid content.

[0133] Implement Comparative Example 8 Others are the same as in Example 1, the difference is that: In a polyester topcoat formula for aluminum single panels of building curtain walls, For the functional resin I, in its preparation method, in S12, The molar ratio of the intermediate 1I, 1H,1H,9H,9H-perfluoro-1,9-nonanediol, ethylene glycol, and glycerol is 0:0.70:0.25:0.15; that is, the intermediate 1I is not added.

[0134] Implement Comparative Example 9 Others are the same as in Example 1, the difference is that: In a polyester topcoat formula for aluminum single panels of building curtain walls, For the functional resin I, in its preparation method, in S12, The molar ratio of the intermediate 1I, 1H,1H,9H,9H-perfluoro-1,9-nonanediol, ethylene glycol, and glycerol is 0.10:0:0.85:0.15; that is, 1H,1H,9H,9H-perfluoro-1,9-nonanediol is not added.

[0135] Implement Comparative Example 10 Others are the same as in Example 1, the difference is that: In a polyester topcoat formula for aluminum single panels of building curtain walls, For the functional resin I, in its preparation method, in S12, The molar ratio of the intermediate 1I, 1H,1H,9H,9H-perfluoro-1,9-nonanediol, ethylene glycol, and glycerol is 0.10:0.70:0.30:0; that is, glycerol is not added.

[0136] Implement Comparative Example 11 Other is the same as Example 1, the difference is that: In a polyester topcoat formulation for aluminum single panels of building curtain walls, For the functional resin II and its preparation method, in S24, The dosage ratio of the intermediate 2I, intermediate 2II, intermediate 2III, and isobornyl methacrylate is 0 g: 0.70 g: 0.25 g: 0.30 g; that is, the intermediate 2I is not added.

[0137] Implement Comparative Example 12 Other is the same as Example 1, the difference is that: In a polyester topcoat formulation for aluminum single panels of building curtain walls, For the functional resin II and its preparation method, in S24, The dosage ratio of the intermediate 2I, intermediate 2II, intermediate 2III, and isobornyl methacrylate is 0.15 g: 0 g: 0.25 g: 0.85 g; that is, the intermediate 2II is not added.

[0138] Implement Comparative Example 13 Other is the same as Example 1, the difference is that: In a polyester topcoat formulation for aluminum single panels of building curtain walls, For the functional resin II and its preparation method, in S24, The dosage ratio of the intermediate 2I, intermediate 2II, intermediate 2III, and isobornyl methacrylate is 0.15 g: 0.70 g: 0 g: 0.40 g; that is, the intermediate 2III is not added.

[0139] Implement Comparative Example 14 Other is the same as Example 1, the difference is that: In a polyester topcoat formulation for aluminum single panels of building curtain walls, For the functional resin II and its preparation method, in S24, Replace the intermediate 2III with isocyanatoethyl methacrylate.

[0140] Implement Comparative Example 15 Other is the same as Example 1, the difference is that: In a polyester topcoat formulation for aluminum single panels of building curtain walls, For the functional resin II and its preparation method, in S24, Replace the isobornyl methacrylate with 2-ethylhexyl acrylate.

[0141] The application method of the polyester topcoat for aluminum single panels of building curtain walls described in the above examples and comparative examples is as follows: (1)After wiping the aluminum single panel with polyester / amino system (or acrylic / amino system) primer with alcohol, it is dried naturally; (2)Add 1.0% PTSA to the polyester topcoat described in the above examples and comparative examples, adjust it to the construction viscosity (thinner: S-150 and ethylene glycol monobutyl ether are mixed at a mass ratio of 1:1), spray it, and let it stand for 30 s; (3)After the topcoat levels out, place it in an oven to dry. Set the board temperature to 230 °C and bake for 90 s to obtain a topcoat layer with a film thickness of 25 ± 2 μm.

[0142] Measure the physical properties of the polyester topcoat layer for a kind of building curtain wall aluminum single panel prepared in the examples and comparative examples of the present invention respectively. The results are shown in Table 1.

[0143] Table 1 Physical test properties of each example Examples Appearance of paint film Adhesion Pencil hardness Impact Acid resistance (5wt%) Humidity and heat resistance Salt spray resistance Artificial aging resistance Water contact angle Storage stability Example 1 Normal Grade 0 3H Passed Passed Passed Passed Passed 126° Normal Example 2 Normal Grade 0 3H Passed Passed Passed Passed Passed 125° Normal Example 3 Normal Grade 0 3H Passed Passed Passed Passed Passed 122° Normal Example 4 Normal Grade 1 3H Passed Passed Passed Passed Passed 120° Normal Example 5 Normal Grade 0 2H Passed Passed Passed Passed Passed 128° Normal Example 6 Normal Grade 1 3H Passed Passed Passed Passed Passed 126° Normal Example 7 Normal Grade 0 2H Passed Passed Passed Passed Passed 124° Normal Example 8 Normal Grade 0 3H Passed Passed Passed Passed Passed 118° Normal Example 9 Normal Grade 1 3H Passed Passed Passed Passed Passed 115° Normal Example 10 Normal Grade 0 2H Passed Passed Passed Passed Passed 126° Normal Example 11 Normal Grade 0 2H Passed Passed Passed Passed Passed 127° Normal Example 12 Normal Grade 1 3H Passed Passed Passed Passed Passed 121° Normal Example 13 Normal Grade 0 3H Passed Passed Passed Passed Passed 119° Normal Example 14 Normal Grade 0 3H Passed Passed Passed Passed Passed 125° Normal Example 15 Normal Grade 0 2H Passed Passed Passed Passed Passed 128° Normal Comparative Example 1 Normal Grade 0 H Passed Rusted and peeled off Peeled off Rusted Peeled off 73° Normal Comparative Example 2 Normal Grade 0 3H Passed Rusted and peeled off Rusted Rusted Blistered 97° Normal Comparative Example 3 Normal Grade 0 3H Slightly peeled off Blistered Blistered Blistered Yellowed 109° Normal Comparative Example 4 Normal Grade 1 3H Peeled off Blistered Blistered Blistered Peeled off 114° Normal Comparative Example 5 Normal Grade 0 2H Passed Blistered Rusted Rusted Cracked 127° Normal Comparative Example 6 Normal Grade 1 3H Slightly peeled off Passed Blistered Blistered Cracked 125° Normal Comparative Example 7 Normal Grade 0 1H Passed Rusted Rusted Peeled off Peeled off 122° Normal Comparative Example 8 Normal Grade 0 3H Passed Passed Passed Passed Yellowed 126° Normal Comparative Example 9 Normal Grade 1 3H Slightly peeled off Rusted and peeled off Rusted Rusted Loss of gloss 98° Normal Comparative Example 10 Normal Grade 0 H Passed Rusted and peeled off Rusted Peeled off Blistered 119° Normal Comparative Example 11 Normal Grade 0 H Passed Blistered Blistered Blistered Cracked 114° Normal Comparative Example 12 Normal Grade 1 3H Peeled off Rusted Rusted Rusted Blistered 103° Normal Comparative Example 13 Normal Grade 0 H Passed Rusted Rusted Peeled off Cracked 122° Normal Comparative Example 14 Normal Grade 1 2H Peeled off Rusted Rusted Rusted Blistered 112° Caked Comparative Example 15 Normal Grade 0 H Passed Rusted Rusted Rusted Bubbled 115° Normal First, compared with Comparative Examples 1-15, the polyester topcoat layer for the building curtain wall aluminum single panel of the present invention has excellent aging resistance, scratch resistance, etc. In addition, it also has excellent stain resistance, etc., and is especially suitable for use in outdoor harsh environments.

[0144] Second, from Example 1 and Comparative Examples 1-3, it can be observed that Functional Resin I and Functional Resin II in the polyester topcoat for the building curtain wall aluminum single panel of the present invention have excellent anti-aging properties, acid resistance, salt spray resistance, and stain resistance (high water contact angle), etc. One of the reasons is that there are a large number of C-F bonds in Functional Resin I and Functional Resin II, which have a high shielding effect on UV light, water vapor, etc.; Third, from Example 1 and Comparative Examples 4-7, it can be observed that the polyester / amino system, suitable pigment-volume ratio and resin-curing agent ratio in the polyester topcoat for the building curtain wall aluminum single panel of the present invention have a significant positive effect on the performance of the topcoat; Fourth, from Example 1 and Comparative Examples 8-10, it can be observed that Modified Resin I in the polyester topcoat for the building curtain wall aluminum single panel of the present invention has a positive effect on improving the aging resistance with the o-hydroxybenzophenone structure in its structure; the C-F structure has a significant positive effect on forming the surface denseness and shielding effect of the topcoat, thereby improving acid resistance, damp heat resistance, salt spray resistance, aging resistance, and stain resistance; the glycerol structure provides additional hydroxyl groups to form crosslinking sites, which plays an important role in increasing the crosslinking density of the paint film; Fifth, it can be observed from Example 1 and Comparative Examples 11-15 that in the polyester topcoat for aluminum single panels of building curtain walls of the present invention, the modified resin II has nano-silicon in its structure, which can improve hardness and increase crosslinking density, thereby enhancing the performance of the paint film; the C-F structure has the same effect of enhancing the surface shielding of the paint film; the hard monomer acrylate can improve hardness; in addition, the blocked polyurethane curing agent can increase crosslinking density to enhance performance, forming a double thermosetting system of polyester / amino and polyester / polyurethane, effectively improving the physical properties of the paint film.

[0145] In summary, the polyester topcoat layer for aluminum single panels of building curtain walls of the present invention has excellent aging resistance, acid resistance, damp heat resistance, salt spray resistance, etc. In addition, it also has excellent stain resistance and impact resistance, can meet outdoor use, and has great practical significance.

[0146] The test methods are as follows: (1) Appearance of paint film: Visual inspection. Requirement: The surface is flat without running marks and bubble phenomena.

[0147] (2) Adhesion: Tested according to the method described in GB / T 9286-2021.

[0148] (3) Hardness: Tested according to the method described in GB / T6739-2006.

[0149] (4) Impact: Tested according to the method described in GB / T 1732-2020, using a φ8mm×1000g×50cm impact tester.

[0150] (5) Acid resistance (5wt%): Tested according to the method described in GB / T 9274-1988, with a test time of 168h. Requirements: No bubbling, no rusting, and no peeling.

[0151] (6) Damp heat resistance: Tested according to the method described in GB / T 1740-2007, with a test time of 1000h. Requirements: No bubbling, no rusting, and no peeling.

[0152] (7) Salt spray resistance: Tested according to the method described in GB / T 1771-2007, with a test time of 1000h. Requirements: No bubbling, no rusting, and no peeling.

[0153] (8) Resistance to artificial aging: Tested according to the method described in GB / T 1865-2009, with a test time of 4000h. Requirements: No loss of gloss, no bubbling, no cracking, no peeling, no chalking, and ΔE≤3.

[0154] (9) Water contact angle: Tested according to the method described in ASTM D 5725 1999(R2008).

[0155] (10)Storage stability: Tested according to the method described in GB / T 6753.3-1986.

[0156] Inspired by the ideal embodiments of the present invention as described above, through the above description, relevant staff can completely make various changes and modifications without departing from the technical idea of this invention. The technical scope of this invention is not limited to the content in the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A polyester topcoat for building curtain wall aluminum veneer, characterized in that: The invention comprises the following raw materials in parts by weight: 20-30 parts of saturated polyester resin; Functional resin I 10-15 parts; Functional resin II 3.0-5.0 parts; 5.0-9.0 parts of amino resin; Pigment 15-25 parts; 12-20 parts of filler; Dispersant 0.2-0.5 parts; Anti-settling agent 0.1-0.3 parts; Defoaming agent 0.1-0.2 parts; Leveling agent 0.5-1.0 part; S-150 solvent 10-15 parts.

2. The polyester topcoat for building curtain wall aluminum veneer according to claim 1, characterized in that: The functional resin I, and its preparation method, comprises the following steps: S11, coupling reaction of 2,4,4'-trihydroxybenzophenone derivative with bromoethanol to obtain intermediate 1I; The molar ratio of the 2,4,4'-trihydroxybenzophenone derivative to bromoethanol is 1:2; S12, subjecting the intermediate product 1I, polyfluorodiol, ethylene glycol, propylene glycol and terephthalic acid to a condensation polymerization reaction under the action of a catalyst to obtain a target product, namely, functional resin I; The molar ratio of the total mole number of the intermediate product II, polyfluorodiol, ethylene glycol, and propylene glycol to terephthalic acid is 1.1:1; and The molar ratio of the intermediate product II, polyfluorodiol, ethylene glycol and propylene glycol is 0.05-0.15: 0.60-0.80: 0.05-0.15: 0.10-0.

20.

3. The polyester topcoat for building curtain wall aluminum veneer according to claim 1, characterized in that: The functional resin II, and its preparation method, comprises the following steps: S21, coupling the nano-silicon with a silane coupling agent containing a carbon-carbon double bond to obtain an intermediate product 2I; The usage ratio of the nano silicon to the silane coupling agent containing a carbon-carbon double bond is 1g:0.1-0.3g; S22, a fluorinated acyl chloride is subjected to a nucleophilic addition reaction with a hydroxy olefin to obtain an intermediate 2II; The fluorine-containing acyl chloride and the hydroxyl olefin are added in a molar ratio of acyl chloride to hydroxyl of 1:1; S23, subjecting isocyanoolefins to a nucleophilic addition reaction with phenol in the presence of an inhibitor and a catalyst to obtain an intermediate product 2III; The isocyanate olefins and phenol are added in a molar ratio of isocyanate group to hydroxyl group of 1:1; S24, subjecting the intermediate product 2I, the intermediate product 2II, the intermediate product 2III, and the acrylate to a free radical polymerization reaction under the action of an initiator to obtain a target product, namely, a functional resin II; The usage ratio of the intermediate product 2I, the intermediate product 2II, the intermediate product 2III and the acrylic ester is 0.15g: 0.60-0.80g: 0.20-0.30g: 0.10-0.20g.

4. The polyester topcoat for building curtain wall aluminum veneer according to claim 2, characterized in that: The 2,4,4'-trihydroxybenzophenone derivative is 2,4,4'-trihydroxybenzophenone or 2,2',4,4'-tetrahydroxybenzophenone; the polyfluorodiol is 1H,1H,9H,9H-perfluoro-1,9-nonanediol or octafluoro-1,6-hexanediol.

5. The polyester topcoat for building curtain wall aluminum veneer according to claim 3, characterized in that: The fluorine-containing acyl chloride is perfluorobutyryl chloride, perfluorooctanoyl chloride or perfluorononanoyl chloride; the hydroxy olefin is an allyl hydroxy structure or a hydroxy acrylate structure; the isocyano olefin is allyl isocyanate or acryloxy isocyanate; and the acrylate is a hard monomer acrylate.

6. The polyester topcoat for building curtain wall aluminum veneer according to claim 1, characterized in that: The hydroxyl value of the saturated polyester resin is a medium hydroxyl polyester.

7. The polyester topcoat for building curtain wall aluminum veneer according to claim 1, characterized in that: The amino resin is a mixture of fully methylated amino resin and partially methylated amino resin.

8. The polyester topcoat for building curtain wall aluminum veneer according to claim 1, characterized in that: The pigment is an inorganic pigment.

9. A method for preparing a polyester topcoat for building curtain wall aluminum veneer, characterized in that: The steps include: S31, paint matching, i.e. Take a portion of the saturated polyester resin in the formula amount, add the S-150 aromatic hydrocarbon solvent in the formula amount, the functional resin I in the formula amount, the dispersant in the formula amount, the anti-settling agent in the formula amount, the pigment in the formula amount and the filler in the formula amount in sequence under low-speed stirring, and then stir at a high speed for 20-30 minutes to obtain a premixed solution I; S32, refining, i.e. Transfer the premixed solution I to a grinder and grind to obtain a mixed solution II with a solid particle size of ≤20 μm; S33, add the remaining raw materials and dilute, that is, The mixed solution II is stirred at a low speed, and the remaining saturated polyester resin, the formulated amount of amino resin, the formulated amount of functional resin II, and the formulated amount of leveling agent are added in sequence; and the viscosity of the mixed solution is adjusted with an appropriate amount of ethylene glycol butyl ether, and the mixture is stirred at a low speed for 8-12 minutes to obtain a mixed solution III; S34, filter, collect, i.e. The mixed solution III is filtered using a filter bag with a pore size of 50 μm, and the filtrate is the polyester topcoat for the building curtain wall aluminum veneer.

10. Use of the polyester topcoat for building curtain wall aluminum veneer according to claim 1 in rolled aluminum curtain wall.