Water-based insulating paint for rail traffic roof as well as preparation method and application of water-based insulating paint

Abstract

The invention belongs to the technical field of coatings, and particularly relates to a water-based insulating coating for rail traffic roofs as well as a preparation method and application of the water-based insulating coating. The water-based insulating paint comprises a primer, a finish paint and a curing agent matched with the primer and the finish paint. The primer is prepared from 20 to 40 parts of waterborne epoxy emulsion A, 20 to 40 parts of waterborne epoxy emulsion B, 1 to 4 parts of dispersing agent, 3 to 6 parts of zinc phosphate, 3 to 6 parts of mica, 3 to 6 parts of silica powder, 5 to 10 parts of titanium dioxide, 5 to 10 parts of talcum powder, 0.3 to 0.8 part of lamp black, 0.1 to 0.4 part of anti-settling agent, 0.1 to 0.4 part of defoaming agent, 0.1 to 0.4 part of wetting flatting agent, 0.1 to 0.4 part of thickening agent and 2 to 6 parts of coalescing agent. Compared with the prior art, the water-based insulating paint prepared by the invention has good salt spray resistance and weather resistance, and also has good voltage resistance, insulativity and electric breakdown resistance.

Description

Technical Field

[0001] The invention belongs to the technical field of coatings, and in particular relates to a water-based insulating coating for a rail transit vehicle roof and a preparation method and application thereof. Background Art

[0002] At present, the vast majority of rail transit vehicles are mainly powered by electricity, and the vehicle body needs to have a certain voltage resistance, especially the voltage at the roof power connection is extremely high. Considering that the general body material is aluminum alloy, the roof insulation treatment is particularly important. At present, vehicle insulation technology mainly relies on spraying insulating paint. Considering that the insulating part is the outside of the body, the roof insulation paint must not only meet the insulation requirements, but also meet the test requirements of rail transit body paint, requiring the paint to have good insulation and high resistance to electrical breakdown, salt spray resistance, weather resistance, flexibility, acid and alkali resistance, and impact resistance.

[0003] At present, epoxy insulating coatings are mostly used for coating of aluminum alloy battery packs. For example, patent CN107418375A discloses a water-based epoxy resin coating and its preparation method. The coating components and weight fractions are: 20-30 parts of epoxy resin, 10-15 parts of distilled water, 10-15 parts of water-soluble cellulose ether, 5-10 parts of polyacrylate, 5-10 parts of titanium dioxide, 4-6 parts of water-based carbon black, 4-6 parts of surfactant, 2-3 parts of leveling agent, 2-3 parts of curing agent, 1-2 parts of defoaming agent, 1-2 parts of bentonite, 1-2 parts of mica powder, and 1-2 parts of dispersant. This patent is a water-based two-component epoxy coating. Through experiments, it was found that the epoxy coating has the following problems on PPO-glass fiber material battery boxes: (1) general adhesion; (2) poor flexibility; (3) poor salt spray performance; (4) general insulation; (5) poor weather resistance.

[0004] Patent CN118440560A discloses a water-based fireproof insulating coating for aluminum alloy battery transport boxes, a preparation method and an application thereof. The fireproof insulating coating comprises the following raw material components in parts by weight: 5-25 parts of water-based epoxy emulsion, 5-25 parts of water-based epoxy resin, 1-4 parts of dispersant, 5-10 parts of titanium dioxide, 5-25 parts of ammonium polyphosphate, 5-25 parts of pentaerythritol, 5-25 parts of melamine, 3-8 parts of zinc phosphate, 1-3 parts of talc, 3-6 parts of mica, 0.1-0.5 parts of anti-settling agent, 0.1-0.5 parts of defoaming agent, 0.1-0.5 parts of wetting and leveling agent, 0.1-0.5 parts of thickener, 2-6 parts of film-forming aid, 2-8 parts of deionized water, and the raw material components of the matching primer curing agent in parts by weight: 20-50 parts of epoxy curing agent, 50-80 parts of deionized water. This patent adds two kinds of water-based polymer epoxy emulsions and uses modified polyamide curing agent as primer. Patent CN118440549A discloses a water-based insulating coating for aluminum alloy battery packs, its preparation method and application, the water-based insulating coating includes the following raw material components in parts by weight: 30-50 parts of water-based acrylic dispersion, 20-40 parts of water-based polyurethane dispersion, 1-4 parts of dispersant, 3-6 parts of mica powder, 3-6 parts of silicon powder, 5-15 parts of titanium dioxide, 0.3-0.8 parts of phthalocyanine blue, 0.1-0.5 parts of anti-settling agent, 0.1-0.5 parts of defoaming agent, 0.1-0.5 parts of wetting and leveling agent, 0.1-0.5 parts of thickener, 2-6 parts of film-forming aid, 0-10 parts of deionized water; matching curing agent: 70-90 parts of curing agent, 10-30 parts of solvent.

[0005] However, the voltage resistance of the coatings in the above two patents is 5000V, the salt spray resistance is only 120 hours, the high temperature and high humidity resistance is only 24 hours, and there is no combination of primer and topcoat. Moreover, considering only the most important insulation performance, it is still difficult to use it as an insulating coating for rail transit vehicle roofs.

[0006] Patent CN113201272A discloses a multi-color low-gloss water-based paint primer and topcoat composition for railway passenger cars. A water-based epoxy primer and a water-based acrylic polyurethane topcoat are sprayed on the metal substrate surface of the railway passenger car to achieve protection, but its water resistance is still limited to 40°C, 48 hours, and salt spray resistance is still limited to 720 hours.

[0007] Therefore, there is still a need for a coating that can have good insulation properties and meet the testing requirements of rail transit body coatings. The coating is required to have good insulation and high resistance to electrical breakdown, salt spray resistance, weather resistance, flexibility, acid and alkali resistance, and impact resistance. Summary of the invention

[0008] The purpose of the present invention is to solve at least one of the above problems and to provide a water-based insulating coating for rail transit vehicle roofs and a preparation method and application thereof, so as to solve the problem that the coating in the prior art cannot have good salt spray resistance and weather resistance while having high insulation properties, so as to achieve a water-based insulating coating with good salt spray resistance and weather resistance, as well as good voltage resistance, insulation and electrical breakdown resistance.

[0009] The purpose of the present invention is achieved through the following technical solutions:

[0010] One of the technical solutions of the present invention is to provide a water-based insulating coating for rail transit vehicle roofs, wherein the water-based insulating coating comprises a primer and a topcoat and a matching curing agent;

[0011] The primer comprises the following raw material components in parts by weight:

[0012] 20-40 parts of water-based epoxy emulsion A, 20-40 parts of water-based epoxy emulsion B, 1-4 parts of dispersant, 3-6 parts of zinc phosphate, 3-6 parts of mica, 3-6 parts of silica powder, 5-10 parts of titanium dioxide, 5-10 parts of talc, 0.3-0.8 parts of lamp black, 0.1-0.4 parts of anti-settling agent, 0.1-0.4 parts of defoaming agent, 0.1-0.4 parts of wetting and leveling agent, 0.1-0.4 parts of thickener, 2-6 parts of film-forming aid, and the solvent is deionized water;

[0013] The primer curing agent comprises the following raw material components in parts by weight: 30-50 parts of epoxy curing agent A, 30-50 parts of epoxy curing agent B, and 10-30 parts of solvent;

[0014] The topcoat comprises the following raw material components in parts by weight:

[0015] 50-90 parts of water-based acrylic dispersion, 1-4 parts of dispersant, 3-6 parts of mica, 3-6 parts of silica powder, 5-10 parts of titanium dioxide, 0.3-0.8 parts of lamp black, 1-3 parts of matting powder, 0.1-0.5 parts of anti-settling agent, 0.1-0.5 parts of defoaming agent, 0.1-0.5 parts of wetting and leveling agent, 0.1-0.5 parts of thickener, 2-6 parts of film-forming aid, the solvent is deionized water;

[0016] The topcoat curing agent comprises the following raw material components in parts by weight: 70-90 parts of a polyurethane curing agent and 10-30 parts of a solvent.

[0017] Further, the primer comprises the following raw material components in parts by weight:

[0018] 25-35 parts of water-based epoxy emulsion A, 25-35 parts of water-based epoxy emulsion B, 2-3 parts of dispersant, 4-5 parts of zinc phosphate, 4-5 parts of mica, 4-5 parts of silica powder, 6-8 parts of titanium dioxide, 6-8 parts of talc, 0.4-0.6 parts of lamp black, 0.2-0.3 parts of anti-settling agent, 0.2-0.3 parts of defoaming agent, 0.2-0.3 parts of wetting and leveling agent, 0.2-0.3 parts of thickener, 2-4 parts of film-forming aid, and the solvent is deionized water;

[0019] The primer curing agent comprises the following raw material components in parts by weight: 35-45 parts of epoxy curing agent A, 35-45 parts of epoxy curing agent B, and 15-25 parts of solvent;

[0020] The topcoat comprises the following raw material components in parts by weight:

[0021] 60-80 parts of water-based acrylic dispersion, 2-3 parts of dispersant, 4-5 parts of mica, 4-5 parts of silica powder, 6-8 parts of titanium dioxide, 0.4-0.6 parts of lamp black, 2-3 parts of matting powder, 0.2-0.4 parts of anti-settling agent, 0.2-0.4 parts of defoaming agent, 0.2-0.4 parts of wetting and leveling agent, 0.2-0.4 parts of thickener, 2-4 parts of film-forming aid, the solvent is deionized water;

[0022] The topcoat curing agent comprises the following raw material components in parts by weight: 75-85 parts of a polyurethane curing agent and 15-25 parts of a solvent.

[0023] Furthermore, the primer comprises the following raw material components in parts by weight:

[0024] 30 parts of water-based epoxy emulsion A, 30 parts of water-based epoxy emulsion B, 2 parts of dispersant, 5 parts of zinc phosphate, 4 parts of mica, 4 parts of silica powder, 7 parts of titanium dioxide, 7 parts of talc, 0.5 parts of lamp black, 0.2 parts of anti-settling agent, 0.2 parts of defoaming agent, 0.2 parts of wetting and leveling agent, 0.2 parts of thickener, 2 parts of film-forming aid, and the solvent is deionized water;

[0025] The primer curing agent comprises the following raw material components in parts by weight: 40 parts of epoxy curing agent A, 40 parts of epoxy curing agent B, and 20 parts of solvent;

[0026] The topcoat comprises the following raw material components in parts by weight:

[0027] 70 parts of water-based acrylic dispersion, 2 parts of dispersant, 4 parts of mica, 4 parts of silica powder, 7 parts of titanium dioxide, 0.5 parts of lamp black, 3 parts of matting powder, 0.3 parts of anti-settling agent, 0.3 parts of defoaming agent, 0.3 parts of wetting and leveling agent, 0.3 parts of thickener, 2 parts of film-forming aid, and the solvent is deionized water;

[0028] The topcoat curing agent comprises the following raw material components in parts by weight: 80 parts of a polyurethane curing agent and 20 parts of a solvent.

[0029] Furthermore, the water-based epoxy emulsion A is a water-based epoxy emulsion with a low epoxy equivalent; the water-based epoxy emulsion B is a water-based epoxy emulsion with a high epoxy equivalent; and the solid content of the water-based acrylic dispersion is 30-50%.

[0030] Furthermore, the solid content of the waterborne epoxy emulsion A is 60-80%, and the solid content of the waterborne epoxy emulsion B is 45-65%.

[0031] The water-based epoxy emulsion A is water-based epoxy emulsion HDE8120, with a solid content of 55-65% and an epoxy equivalent of 300-500. The lower epoxy equivalent means that the water-based epoxy emulsion A has more unopened epoxy rings, so that it has higher reactivity and higher cross-linking density, as well as good adhesion and chemical resistance, so that it has good water resistance, chemical resistance, solvent resistance, adhesion, salt spray resistance and other characteristics.

[0032] The waterborne epoxy emulsion B is waterborne epoxy resin HDE8370, with a solid content of 50-60% and an epoxy equivalent of 1500-2500. A larger epoxy equivalent also means that it has a larger molecular weight, a lower epoxy ring (reactive group) content and a lower crosslinking density, so that it has good flexibility, adhesion, resistance to electrical breakdown and other characteristics.

[0033] The water-based acrylic dispersion is water-based acrylic dispersion AQUAPAC-8246, with a solid content of 40-50%, and has the characteristics of good adhesion, good flexibility, good water resistance, good weather resistance, good electrical breakdown resistance and the like.

[0034] Furthermore, the epoxy curing agent A is a polyamide curing agent with a low active hydrogen equivalent; and the epoxy curing agent B is a polyamide curing agent with a high active hydrogen equivalent.

[0035] Furthermore, the polyurethane curing agent is HDI isocyanate curing agent.

[0036] Furthermore, the epoxy curing agent A is preferably a water-based epoxy curing agent HDH5200, with an active hydrogen equivalent of 200-400. A larger active hydrogen equivalent means that it has a larger molecular weight and a lower reactive group, so that the paint film has a lower cross-linking density, so that it has good adhesion, flexibility, water resistance, salt spray resistance and other characteristics.

[0037] Furthermore, the epoxy curing agent B is preferably a water-based epoxy curing agent HDH6815, with an active hydrogen equivalent of 100-150. A lower active hydrogen equivalent means that it has a lower molecular weight and a higher reactive group, so that the paint film has a higher cross-linking density, so that it has good drying speed, higher hardness, good chemical resistance, solvent resistance, electrical breakdown resistance, water resistance and the like.

[0038] Furthermore, the polyurethane curing agent is an HDI isocyanate curing agent, preferably a water-based HDI isocyanate curing agent Uapoly3598T, whose NCO content is 20-25%, and has the characteristics of fast curing speed, good water resistance, good chemical and solvent resistance, good adhesion, high hardness, good flexibility and the like.

[0039] Furthermore, the mica is 800 mesh air-selected mica, the silicon micropowder is ultrafine silicon micropowder, and the zinc phosphate is 800 mesh water-based special zinc phosphate.

[0040] Furthermore, the mica is preferably mica GB-3, which has the characteristics of easy dispersion, good insulation, good water resistance, etc.; the silicon micropowder is preferably silicon micropowder 702, which has the characteristics of easy dispersion, good insulation, etc.; the zinc phosphate is preferably zinc phosphate ZP-50, which has the characteristics of easy dispersion, good rust resistance, good stability, good water resistance, etc.

[0041] Furthermore, the dispersant is Tego750; the anti-settling agent is M5; the defoaming agent is Tego810; the wetting and leveling agent is Tego280; the thickener is Tego3060; and the matting powder is E-1011.

[0042] Furthermore, the titanium dioxide is R996; the talcum powder is 800 mesh; and the lamp black is 101 lamp black.

[0043] Furthermore, the film-forming aid is prepared by mixing ethylene glycol monobutyl ether and dipropylene glycol butyl ether in a mass ratio of 1:(1-2), and the solvent is propylene glycol diacetate.

[0044] The second technical solution of the present invention is to provide a method for preparing a water-based insulating coating for a rail transit vehicle roof, the method for preparing the water-based insulating coating comprising the following steps:

[0045] (1) preparing a primer: adding a dispersant, a defoamer, an anti-settling agent, titanium dioxide, mica powder, silica powder, talcum powder, lamp black, and zinc phosphate to water in sequence, stirring and grinding, adding water-based epoxy emulsion A, water-based epoxy emulsion B, a wetting and leveling agent, a film-forming aid, and a thickener to the ground slurry, and adding deionized water to obtain a primer;

[0046] (2) Preparation of topcoat: Add dispersant, defoamer, anti-settling agent, titanium dioxide, mica powder, silica powder and lamp black to water in sequence, stir and grind evenly, add water-based acrylic dispersion, wetting and leveling agent, film-forming aid, matting powder and thickener to the ground slurry, add deionized water to obtain topcoat.

[0047] Furthermore, the preparation method of the primer of the water-based insulating coating comprises the following steps:

[0048] S1: Weigh part of the deionized water and put it into the tank, weigh the dispersant and defoamer and add them into the tank and stir at a low speed;

[0049] S2: weigh the anti-settling agent, titanium dioxide, mica, silica powder, talcum powder, lamp black and zinc phosphate and put them into a tank and stir at high speed;

[0050] S3: grinding the slurry by a grinder;

[0051] S4: putting the ground slurry into an emulsion tank and stirring at medium speed;

[0052] S5: Add water-based epoxy emulsion A and water-based epoxy emulsion B into a tank and stir at medium speed;

[0053] S6: Put the wetting and leveling agent, ethylene glycol monobutyl ether, dipropylene glycol butyl ether, the remaining deionized water and the thickener into a tank and stir at a medium speed to obtain the primer of the water-based insulating coating.

[0054] Furthermore, the method for preparing the topcoat of the water-based insulating coating comprises the following steps:

[0055] T1: Weigh some deionized water and put it into the tank, weigh the dispersant and defoamer and add them into the tank and stir at low speed;

[0056] T2: Weigh the anti-settling agent, titanium dioxide, mica, silica powder and lampblack and put them into a tank and stir at high speed;

[0057] T3: grinding the slurry through a grinder;

[0058] T4: Put the ground slurry into the emulsion tank and stir at medium speed;

[0059] T5: Add the water-based acrylic dispersion into the tank and stir at medium speed;

[0060] T6: Put the wetting and leveling agent, matting powder, ethylene glycol monobutyl ether, dipropylene glycol butyl ether, the remaining deionized water and the thickener into a tank and stir at a medium speed to obtain the topcoat of the water-based insulating coating.

[0061] Furthermore, the low-speed stirring is 200-300 rpm, the medium-speed stirring is 300-500 rpm, and the high-speed stirring is 500-700 rpm.

[0062] The third technical solution of the present invention is to provide an application of a water-based insulating coating for a rail transit vehicle roof, wherein the water-based insulating coating is used for surface coating of a rail transit vehicle roof.

[0063] Compared with the prior art, the present invention has the following advantages:

[0064] The water-based insulating coating of the present invention comprises a primer and a topcoat, and the primer and the topcoat are respectively mixed with a curing agent before coating, and the bottom and top coating processes ensure good salt spray resistance and weather resistance while having good voltage resistance, insulation and electrical breakdown resistance. The primer is added with a water-based epoxy emulsion A with a lower epoxy equivalent and a water-based epoxy emulsion B with a higher epoxy equivalent, and is matched with an epoxy curing agent A with a higher active hydrogen equivalent and an epoxy curing agent B with a lower active hydrogen equivalent, so that the primer has good adhesion, salt spray resistance, insulation, electrical breakdown resistance and the like on an aluminum alloy material. The topcoat is added with a water-based acrylic dispersion with a solid content of 40-50%, and is matched with an HDI isocyanate curing agent with an NCO content of 20-25%, so that the topcoat has good insulation, electrical breakdown resistance, weather resistance, chemical resistance and the like. In addition, mica and silicon micropowder are added to further improve the voltage resistance and electrical breakdown resistance of the paint film. The addition of zinc phosphate further improves the salt spray and water resistance. DETAILED DESCRIPTION

[0065] The present invention is described in detail below in conjunction with specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0066] In the following specific implementations, the materials used are all commercially available and can be purchased. The specific models of the materials are shown in Table 1:

[0067] Table 1: Models of materials required for the preparation of water-based insulating coatings for rail transit vehicle roofs

[0068] Waterborne Epoxy Emulsion A Water-based epoxy emulsion HDE8120 Waterborne epoxy emulsion B Waterborne epoxy resin HDE8370 Waterborne acrylic dispersion Waterborne acrylic dispersion AQUAPAC-8246 Dispersants Dispersant Tego750 Titanium dioxide Titanium Dioxide R996 Mica Mica GB-3 Silica powder Silica powder 702 Zinc phosphate Zinc phosphate ZP-50 talcum powder 800 mesh talcum powder Light Black 101 Light Black Anti-settling agent Anti-settling agent M5 Defoaming agent Defoamer Tego810 Wetting and leveling agent Wetting and leveling agent Tego280 Thickener Thickener Tego3060 Matting powder Matting powder E-1011 Epoxy Curing Agent A Waterborne epoxy curing agent HDH5200 Epoxy Curing Agent B Waterborne epoxy curing agent HDH6815 Polyurethane curing agent Water-based curing agent Uapoly3598T Curing agent solvent Propylene glycol diacetate Film former Ethylene glycol monobutyl ether: dipropylene glycol butyl ether = 1:1

[0069] Example 1

[0070] This embodiment provides a water-based insulating coating for rail transit vehicle roof and a preparation method thereof, wherein the water-based insulating coating comprises a primer and a topcoat and a matching curing agent;

[0071] The primer comprises the following raw material components in parts by weight:

[0072] 30 parts of water-based epoxy emulsion A, 30 parts of water-based epoxy emulsion B, 2 parts of dispersant, 5 parts of zinc phosphate, 4 parts of mica, 4 parts of silica powder, 7 parts of titanium dioxide, 7 parts of talc, 0.5 parts of lamp black, 0.2 parts of anti-settling agent, 0.2 parts of defoaming agent, 0.2 parts of wetting and leveling agent, 0.2 parts of thickener, 2 parts of film-forming aid, 8 parts of deionized water as solvent;

[0073] The primer curing agent comprises the following raw material components in parts by weight: 40 parts of epoxy curing agent A, 40 parts of epoxy curing agent A, and 20 parts of solvent;

[0074] The topcoat comprises the following raw material components in parts by weight:

[0075] 70 parts of water-based acrylic dispersion, 2 parts of dispersant, 4 parts of mica, 4 parts of silica powder, 7 parts of titanium dioxide, 0.5 parts of lamp black, 3 parts of matting powder, 0.3 parts of anti-settling agent, 0.3 parts of defoaming agent, 0.3 parts of wetting and leveling agent, 0.3 parts of thickener, 2 parts of film-forming aid, and 6 parts of deionized water as solvent;

[0076] The topcoat curing agent comprises the following raw material components in parts by weight: 80 parts of a polyurethane curing agent and 20 parts of a solvent.

[0077] The preparation method of the primer of the water-based insulating coating comprises the following steps:

[0078] S1: Weigh part of the deionized water and put it into the tank, weigh the dispersant and defoamer and add them into the tank, and stir at a low speed of 200-300 rpm for 20 minutes;

[0079] S2: weigh the anti-settling agent, titanium dioxide, mica, silica powder, talcum powder, lamp black and zinc phosphate and put them into a tank, and stir them at a high speed of 500-700 rpm for 30 minutes;

[0080] S3: Grind the slurry to a fineness of less than 30 microns through a grinder;

[0081] S4: putting the ground slurry into an emulsion tank and stirring at a medium speed of 300-500 rpm for 30 minutes;

[0082] S5: Add water-based epoxy emulsion A and water-based epoxy emulsion B into a tank and stir at a medium speed of 300-500 rpm for 20 minutes;

[0083] S6: Put the wetting and leveling agent, ethylene glycol monobutyl ether, dipropylene glycol butyl ether, the remaining deionized water and the thickener into a tank, and stir at a medium speed of 300-500 rpm for 30 minutes to obtain the primer of the water-based insulating coating.

[0084] The preparation method of the topcoat of the water-based insulating coating comprises the following steps:

[0085] T1: Weigh part of the deionized water and put it into the tank, weigh the dispersant and defoamer and add them into the tank, and stir at a low speed of 200-300 rpm for 20 minutes;

[0086] T2: Weigh the anti-settling agent, titanium dioxide, mica, silica powder and lampblack and put them into a tank, and stir at a high speed of 500-700 rpm for 30 minutes;

[0087] T3: Grind the slurry to a fineness of less than 30 microns through a grinder;

[0088] T4: put the ground slurry into the emulsion tank and stir at a medium speed of 300-500 rpm for 30 minutes;

[0089] T5: Add the water-based acrylic dispersion into the tank and stir at a medium speed of 300-500 rpm for 20 minutes;

[0090] T6: Put the wetting and leveling agent, matting powder, ethylene glycol monobutyl ether, dipropylene glycol butyl ether, remaining deionized water and thickener into a tank, stir at a medium speed of 300-500 rpm for 30 minutes to obtain the topcoat of the water-based insulating coating.

[0091] The primer obtained in the embodiment was mixed with the primer curing agent in a ratio of 100:20, and the topcoat was mixed with the topcoat curing agent in a ratio of 100:40, and then coated and the paint film performance test was carried out, specifically including a 100-grid adhesion performance test, an impact resistance performance test, a pull-off performance test, a flexibility test, a water resistance performance test, a high temperature and high humidity performance test, a voltage resistance performance test, a salt spray performance test, a weather resistance performance test, and a MEK resistance performance test.

[0092] Example 2

[0093] This embodiment provides a water-based insulating coating for a rail transit vehicle roof, wherein the water-based insulating coating comprises a primer and a topcoat and a matching curing agent;

[0094] The primer comprises the following raw material components in parts by weight:

[0095] 25 parts of water-based epoxy emulsion A, 35 parts of water-based epoxy emulsion B, 2 parts of dispersant, 4 parts of zinc phosphate, 4 parts of mica, 4 parts of silica powder, 7 parts of titanium dioxide, 7 parts of talc, 0.5 parts of lamp black, 0.2 parts of anti-settling agent, 0.2 parts of defoaming agent, 0.2 parts of wetting and leveling agent, 0.2 parts of thickener, 2 parts of film-forming aid, 9 parts of deionized water as solvent;

[0096] The primer curing agent includes the following raw material components in parts by weight: 35 parts of epoxy curing agent A, 45 parts of epoxy curing agent B, and 20 parts of solvent;

[0097] The topcoat comprises the following raw material components in parts by weight:

[0098] 75 parts of water-based acrylic dispersion, 2 parts of dispersant, 4 parts of mica, 4 parts of silica powder, 6 parts of titanium dioxide, 0.4 parts of lamp black, 2 parts of matting powder, 0.4 parts of anti-settling agent, 0.4 parts of defoaming agent, 0.4 parts of wetting and leveling agent, 0.4 parts of thickener, 2 parts of film-forming aid, 3 parts of deionized water;

[0099] The topcoat curing agent comprises the following raw material components in parts by weight: 75 parts of a polyurethane curing agent and 25 parts of a solvent.

[0100] The preparation method of the primer and topcoat of the water-based insulating coating in Example 2 is the same as that in Example 1.

[0101] Example 3

[0102] This embodiment provides a water-based insulating coating for a rail transit vehicle roof, wherein the water-based insulating coating comprises a primer and a topcoat and a matching curing agent;

[0103] The primer comprises the following raw material components in parts by weight:

[0104] 35 parts of water-based epoxy emulsion A, 25 parts of water-based epoxy emulsion B, 3 parts of dispersant, 5 parts of zinc phosphate, 5 parts of mica, 5 parts of silica powder, 6 parts of titanium dioxide, 6 parts of talc, 0.6 parts of lamp black, 0.3 parts of anti-settling agent, 0.3 parts of defoaming agent, 0.3 parts of wetting and leveling agent, 0.3 parts of thickener, 4 parts of film-forming aid, and 4 parts of deionized water as solvent;

[0105] The primer curing agent comprises the following raw material components in parts by weight: 45 parts of epoxy curing agent A, 35 parts of epoxy curing agent B, and 20 parts of solvent;

[0106] The topcoat comprises the following raw material components in parts by weight:

[0107] 60 parts of water-based acrylic dispersion, 4 parts of dispersant, 5 parts of mica, 5 parts of silica powder, 8 parts of titanium dioxide, 0.6 parts of lamp black, 3 parts of matting powder, 0.2 parts of anti-settling agent, 0.2 parts of defoaming agent, 0.2 parts of wetting and leveling agent, 0.2 parts of thickener, 4 parts of film-forming aid, and 10 parts of deionized water as solvent;

[0108] The topcoat curing agent comprises the following raw material components in parts by weight: 85 parts of polyurethane curing agent B and 15 parts of solvent.

[0109] The preparation method of the primer and topcoat of the water-based insulating coating in Example 3 is the same as that in Example 1.

[0110] Comparative Example 1

[0111] This comparative example provides a water-based insulating coating for rail transit vehicle roof and a preparation method thereof, wherein the water-based insulating coating comprises a primer and a topcoat and a matching curing agent;

[0112] The primer comprises the following raw material components in parts by weight:

[0113] 60 parts of water-based epoxy emulsion A, 10 parts of water-based epoxy emulsion B, 2 parts of dispersant, 5 parts of zinc phosphate, 4 parts of mica, 4 parts of silica powder, 7 parts of titanium dioxide, 7 parts of talc, 0.5 parts of lamp black, 0.2 parts of anti-settling agent, 0.2 parts of defoaming agent, 0.2 parts of wetting and leveling agent, 0.2 parts of thickener, 2 parts of film-forming aid, and 8 parts of deionized water as solvent;

[0114] The primer curing agent comprises the following raw material components in parts by weight: 40 parts of epoxy curing agent A, 40 parts of epoxy curing agent B, and 20 parts of solvent;

[0115] The topcoat comprises the following raw material components in parts by weight:

[0116] 70 parts of water-based acrylic dispersion, 2 parts of dispersant, 4 parts of mica, 4 parts of silica powder, 7 parts of titanium dioxide, 0.5 parts of lamp black, 3 parts of matting powder, 0.3 parts of anti-settling agent, 0.3 parts of defoaming agent, 0.3 parts of wetting and leveling agent, 0.3 parts of thickener, 2 parts of film-forming aid, and 6 parts of deionized water as solvent;

[0117] The topcoat curing agent comprises the following raw material components in parts by weight: 80 parts of a polyurethane curing agent and 20 parts of a solvent.

[0118] The preparation method of the primer and topcoat of the water-based insulating coating in Comparative Example 1 is the same as that in Example 1.

[0119] The primer obtained in Comparative Example 1 was mixed with the primer curing agent in the ratio of 100:20, and the topcoat was mixed with the topcoat curing agent in the ratio of 100:40, and then coated and the paint film performance test was carried out, specifically including a 100-grid adhesion performance test, an impact resistance performance test, a pull-off performance test, a flexibility test, a water resistance performance test, a high temperature and high humidity performance test, a voltage resistance performance test, a salt spray performance test, a weather resistance performance test, and a MEK resistance performance test.

[0120] Comparative Example 2

[0121] This comparative example provides a water-based insulating coating and a preparation method thereof, wherein the water-based insulating coating comprises a primer and a topcoat and a matching curing agent;

[0122] The primer comprises the following raw material components in parts by weight:

[0123] 0 parts of water-based epoxy emulsion A, 60 parts of water-based epoxy emulsion B, 2 parts of dispersant, 5 parts of zinc phosphate, 4 parts of mica, 4 parts of silica powder, 7 parts of titanium dioxide, 7 parts of talc, 0.5 parts of lamp black, 0.2 parts of anti-settling agent, 0.2 parts of defoaming agent, 0.2 parts of wetting and leveling agent, 0.2 parts of thickener, 2 parts of film-forming aid, 8 parts of deionized water as solvent;

[0124] The primer curing agent comprises the following raw material components in parts by weight: 40 parts of epoxy curing agent A, 40 parts of epoxy curing agent A, and 20 parts of solvent;

[0125] The topcoat comprises the following raw material components in parts by weight:

[0126] 70 parts of water-based acrylic dispersion, 2 parts of dispersant, 4 parts of mica, 4 parts of silica powder, 7 parts of titanium dioxide, 0.5 parts of lamp black, 3 parts of matting powder, 0.3 parts of anti-settling agent, 0.3 parts of defoaming agent, 0.3 parts of wetting and leveling agent, 0.3 parts of thickener, 2 parts of film-forming aid, and 6 parts of deionized water as solvent;

[0127] The topcoat curing agent comprises the following raw material components in parts by weight: 80 parts of a polyurethane curing agent and 20 parts of a solvent.

[0128] The preparation method of the primer and topcoat of the water-based insulating coating in Comparative Example 2 is the same as that in Example 1.

[0129] The primer obtained in Comparative Example 2 was mixed with the primer curing agent in the ratio of 100:20, and the topcoat was mixed with the topcoat curing agent in the ratio of 100:40, and then coated and the paint film performance test was carried out, specifically including a 100-grid adhesion performance test, an impact resistance performance test, a pull-off performance test, a flexibility test, a water resistance performance test, a high temperature and high humidity performance test, a voltage resistance performance test, a salt spray performance test, a weather resistance performance test, and a MEK resistance performance test.

[0130] Comparative Example 3

[0131] This comparative example provides a water-based insulating coating and a preparation method thereof, wherein the water-based insulating coating comprises a primer and a topcoat and a matching curing agent;

[0132] The primer comprises the following raw material components in parts by weight:

[0133] 30 parts of water-based epoxy emulsion A, 30 parts of water-based epoxy emulsion B, 2 parts of dispersant, 5 parts of zinc phosphate, 0 parts of mica, 4 parts of silica powder, 7 parts of titanium dioxide, 7 parts of talc, 0.5 parts of lamp black, 0.2 parts of anti-settling agent, 0.2 parts of defoaming agent, 0.2 parts of wetting and leveling agent, 0.2 parts of thickener, 2 parts of film-forming aid, and 12 parts of deionized water as solvent;

[0134] The primer curing agent comprises the following raw material components in parts by weight: 40 parts of epoxy curing agent A, 40 parts of epoxy curing agent A, and 20 parts of solvent;

[0135] The topcoat comprises the following raw material components in parts by weight:

[0136] 70 parts of water-based acrylic dispersion, 2 parts of dispersant, 4 parts of mica, 4 parts of silica powder, 7 parts of titanium dioxide, 0.5 parts of lamp black, 3 parts of matting powder, 0.3 parts of anti-settling agent, 0.3 parts of defoaming agent, 0.3 parts of wetting and leveling agent, 0.3 parts of thickener, 2 parts of film-forming aid, and 6 parts of deionized water as solvent;

[0137] The topcoat curing agent comprises the following raw material components in parts by weight: 80 parts of a polyurethane curing agent and 20 parts of a solvent.

[0138] The preparation method of the primer and topcoat of the water-based insulating coating in Comparative Example 3 is the same as that in Example 1.

[0139] The primer obtained in Comparative Example 3 was mixed with the primer curing agent in the ratio of 100:20, and the topcoat was mixed with the topcoat curing agent in the ratio of 100:40, and then coated and the paint film performance test was carried out, specifically including a 100-grid adhesion performance test, an impact resistance performance test, a pull-off performance test, a flexibility test, a water resistance performance test, a high temperature and high humidity performance test, a voltage resistance performance test, a salt spray performance test, a weather resistance performance test, and a MEK resistance performance test.

[0140] Comparative Example 4

[0141] This comparative example provides a water-based insulating coating and a preparation method thereof, wherein the water-based insulating coating comprises a primer and a topcoat and a matching curing agent;

[0142] The primer comprises the following raw material components in parts by weight:

[0143] 30 parts of water-based epoxy emulsion A, 30 parts of water-based epoxy emulsion B, 2 parts of dispersant, 5 parts of zinc phosphate, 4 parts of mica, 0 parts of silica powder, 7 parts of titanium dioxide, 7 parts of talc, 0.5 parts of lamp black, 0.2 parts of anti-settling agent, 0.2 parts of defoaming agent, 0.2 parts of wetting and leveling agent, 0.2 parts of thickener, 2 parts of film-forming aid, and 12 parts of deionized water as solvent;

[0144] The primer curing agent comprises the following raw material components in parts by weight: 40 parts of epoxy curing agent A, 40 parts of epoxy curing agent A, and 20 parts of solvent;

[0145] The topcoat comprises the following raw material components in parts by weight:

[0146] 70 parts of water-based acrylic dispersion, 2 parts of dispersant, 4 parts of mica, 4 parts of silica powder, 7 parts of titanium dioxide, 0.5 parts of lamp black, 3 parts of matting powder, 0.3 parts of anti-settling agent, 0.3 parts of defoaming agent, 0.3 parts of wetting and leveling agent, 0.3 parts of thickener, 2 parts of film-forming aid, and 6 parts of deionized water as solvent;

[0147] The topcoat curing agent comprises the following raw material components in parts by weight: 80 parts of a polyurethane curing agent and 20 parts of a solvent.

[0148] The preparation method of the primer and topcoat of the water-based insulating coating in Comparative Example 4 is the same as that in Example 1.

[0149] The primer obtained in Comparative Example 4 was mixed with the primer curing agent in the ratio of 100:20, and the topcoat was mixed with the topcoat curing agent in the ratio of 100:40, and then coated and the paint film performance test was carried out, specifically including a 100-grid adhesion performance test, an impact resistance performance test, a pull-off performance test, a flexibility test, a water resistance performance test, a high temperature and high humidity performance test, a voltage resistance performance test, a salt spray performance test, a weather resistance performance test, and a MEK resistance performance test.

[0150] Comparative Example 5

[0151] This comparative example provides a water-based insulating coating for rail transit vehicle roof and a preparation method thereof, wherein the water-based insulating coating comprises a primer and a topcoat and a matching curing agent;

[0152] The primer comprises the following raw material components in parts by weight:

[0153] 30 parts of water-based epoxy emulsion A, 30 parts of water-based epoxy emulsion B, 2 parts of dispersant, 5 parts of zinc phosphate, 4 parts of mica, 4 parts of silica powder, 7 parts of titanium dioxide, 7 parts of talc, 0.5 parts of lamp black, 0.2 parts of anti-settling agent, 0.2 parts of defoaming agent, 0.2 parts of wetting and leveling agent, 0.2 parts of thickener, 2 parts of film-forming aid, 8 parts of deionized water as solvent;

[0154] The primer curing agent comprises the following raw material components in parts by weight: 80 parts of epoxy curing agent A, 0 parts of epoxy curing agent A, and 20 parts of solvent;

[0155] The topcoat comprises the following raw material components in parts by weight:

[0156] 70 parts of water-based acrylic dispersion, 2 parts of dispersant, 4 parts of mica, 4 parts of silica powder, 7 parts of titanium dioxide, 0.5 parts of lamp black, 3 parts of matting powder, 0.3 parts of anti-settling agent, 0.3 parts of defoaming agent, 0.3 parts of wetting and leveling agent, 0.3 parts of thickener, 2 parts of film-forming aid, and 6 parts of deionized water as solvent;

[0157] The topcoat curing agent comprises the following raw material components in parts by weight: 80 parts of a polyurethane curing agent and 20 parts of a solvent.

[0158] The preparation method of the primer and topcoat of the water-based insulating coating in Comparative Example 5 is the same as that in Example 1.

[0159] The primer obtained in Comparative Example 5 was mixed with the primer curing agent in the ratio of 100:20, and the topcoat was mixed with the topcoat curing agent in the ratio of 100:40, and then coated and the paint film performance test was carried out, specifically including a 100-grid adhesion performance test, an impact resistance performance test, a pull-off performance test, a flexibility test, a water resistance performance test, a high temperature and high humidity performance test, a voltage resistance performance test, a salt spray performance test, a weather resistance performance test, and a MEK resistance performance test.

[0160] Comparative Example 6

[0161] This comparative example provides a water-based insulating coating and a preparation method thereof, wherein the water-based insulating coating comprises a primer and a topcoat and a matching curing agent;

[0162] The primer comprises the following raw material components in parts by weight:

[0163] 30 parts of water-based epoxy emulsion A, 30 parts of water-based epoxy emulsion B, 2 parts of dispersant, 5 parts of zinc phosphate, 4 parts of mica, 4 parts of silica powder, 7 parts of titanium dioxide, 7 parts of talc, 0.5 parts of lamp black, 0.2 parts of anti-settling agent, 0.2 parts of defoaming agent, 0.2 parts of wetting and leveling agent, 0.2 parts of thickener, 2 parts of film-forming aid, 8 parts of deionized water as solvent;

[0164] The primer curing agent comprises the following raw material components in parts by weight: 0 parts of epoxy curing agent A, 80 parts of epoxy curing agent A, and 20 parts of solvent;

[0165] The topcoat comprises the following raw material components in parts by weight:

[0166] 70 parts of water-based acrylic dispersion, 2 parts of dispersant, 4 parts of mica, 4 parts of silica powder, 7 parts of titanium dioxide, 0.5 parts of lamp black, 3 parts of matting powder, 0.3 parts of anti-settling agent, 0.3 parts of defoaming agent, 0.3 parts of wetting and leveling agent, 0.3 parts of thickener, 2 parts of film-forming aid, and 6 parts of deionized water as solvent;

[0167] The topcoat curing agent comprises the following raw material components in parts by weight: 80 parts of a polyurethane curing agent and 20 parts of a solvent.

[0168] The preparation method of the primer and topcoat of the water-based insulating coating in Comparative Example 6 is the same as that in Example 1.

[0169] The primer obtained in Comparative Example 6 was mixed with the primer curing agent in the ratio of 100:20, and the topcoat was mixed with the topcoat curing agent in the ratio of 100:40, and then coated and the paint film performance test was carried out, specifically including a 100-grid adhesion performance test, an impact resistance performance test, a pull-off performance test, a flexibility test, a water resistance performance test, a high temperature and high humidity performance test, a voltage resistance performance test, a salt spray performance test, a weather resistance performance test, and a MEK resistance performance test.

[0170] Comparative Example 7

[0171] This comparative example provides a water-based insulating coating for rail transit vehicle roof and a preparation method thereof, wherein the water-based insulating coating comprises a primer and a topcoat and a matching curing agent;

[0172] The primer comprises the following raw material components in parts by weight:

[0173] 30 parts of water-based epoxy emulsion A, 30 parts of water-based epoxy emulsion B, 2 parts of dispersant, 5 parts of zinc phosphate, 4 parts of mica, 4 parts of silica powder, 7 parts of titanium dioxide, 7 parts of talc, 0.5 parts of lamp black, 0.2 parts of anti-settling agent, 0.2 parts of defoaming agent, 0.2 parts of wetting and leveling agent, 0.2 parts of thickener, 2 parts of film-forming aid, 8 parts of deionized water as solvent;

[0174] The primer curing agent comprises the following raw material components in parts by weight: 40 parts of epoxy curing agent A, 40 parts of epoxy curing agent A, and 20 parts of solvent;

[0175] The topcoat comprises the following raw material components in parts by weight:

[0176] 70 parts of water-based acrylic dispersion, 2 parts of dispersant, 0 parts of mica, 0 parts of silica powder, 7 parts of titanium dioxide, 0.5 parts of lamp black, 3 parts of matting powder, 0.3 parts of anti-settling agent, 0.3 parts of defoaming agent, 0.3 parts of wetting and leveling agent, 0.3 parts of thickener, 2 parts of film-forming aid, and 14 parts of deionized water as solvent;

[0177] The topcoat curing agent comprises the following raw material components in parts by weight: 80 parts of a polyurethane curing agent and 20 parts of a solvent.

[0178] The preparation method of the primer and topcoat of the water-based insulating coating in Comparative Example 7 is the same as that in Example 1.

[0179] The primer obtained in Comparative Example 7 was mixed with the primer curing agent in the ratio of 100:20, and the topcoat was mixed with the topcoat curing agent in the ratio of 100:40, and then coated and the paint film performance test was carried out, specifically including a 100-grid adhesion performance test, an impact resistance performance test, a pull-off performance test, a flexibility test, a water resistance performance test, a high temperature and high humidity performance test, a voltage resistance performance test, a salt spray performance test, a weather resistance performance test, and a MEK resistance performance test.

[0180] Comparative Example 8

[0181] This comparative example provides a water-based insulating coating and a preparation method thereof, wherein the water-based insulating coating comprises a primer and a topcoat and a matching curing agent;

[0182] The primer comprises the following raw material components in parts by weight:

[0183] 30 parts of water-based epoxy emulsion A, 30 parts of water-based epoxy emulsion B, 2 parts of dispersant, 5 parts of zinc phosphate, 4 parts of mica, 4 parts of silica powder, 7 parts of titanium dioxide, 7 parts of talc, 0.5 parts of lamp black, 0.2 parts of anti-settling agent, 0.2 parts of defoaming agent, 0.2 parts of wetting and leveling agent, 0.2 parts of thickener, 2 parts of film-forming aid, 8 parts of deionized water as solvent;

[0184] The primer curing agent comprises the following raw material components in parts by weight: 40 parts of epoxy curing agent A, 40 parts of epoxy curing agent A, and 20 parts of solvent;

[0185] The topcoat comprises the following raw material components in parts by weight:

[0186] 50 parts of water-based acrylic dispersion, 2 parts of dispersant, 4 parts of mica, 4 parts of silica powder, 7 parts of titanium dioxide, 0.5 parts of lamp black, 3 parts of matting powder, 0.3 parts of anti-settling agent, 0.3 parts of defoaming agent, 0.3 parts of wetting and leveling agent, 0.3 parts of thickener, 2 parts of film-forming aid, and 26 parts of deionized water as solvent;

[0187] The topcoat curing agent comprises the following raw material components in parts by weight: 80 parts of a polyurethane curing agent and 20 parts of a solvent.

[0188] The preparation method of the primer and topcoat of the water-based insulating coating in Comparative Example 8 is the same as that in Example 1.

[0189] The primer obtained in Comparative Example 8 was mixed with the primer curing agent in the ratio of 100:20, and the topcoat was mixed with the topcoat curing agent in the ratio of 100:40, and then coated and the paint film performance test was carried out, specifically including a 100-grid adhesion performance test, an impact resistance performance test, a pull-off performance test, a flexibility test, a water resistance performance test, a high temperature and high humidity performance test, a voltage resistance performance test, a salt spray performance test, a weather resistance performance test, and a MEK resistance performance test.

[0190] Comparative Example 9

[0191] This comparative example provides a water-based insulating coating and a preparation method thereof, wherein the water-based insulating coating comprises a primer and a topcoat and a matching curing agent;

[0192] The primer comprises the following raw material components in parts by weight:

[0193] 30 parts of water-based epoxy emulsion A, 30 parts of water-based epoxy emulsion B, 2 parts of dispersant, 5 parts of zinc phosphate, 4 parts of mica, 4 parts of silica powder, 7 parts of titanium dioxide, 7 parts of talc, 0.5 parts of lamp black, 0.2 parts of anti-settling agent, 0.2 parts of defoaming agent, 0.2 parts of wetting and leveling agent, 0.2 parts of thickener, 2 parts of film-forming aid, 8 parts of deionized water as solvent;

[0194] The primer curing agent comprises the following raw material components in parts by weight: 40 parts of epoxy curing agent A, 40 parts of epoxy curing agent A, and 20 parts of solvent;

[0195] The topcoat comprises the following raw material components in parts by weight:

[0196] 78 parts of water-based acrylic dispersion, 2 parts of dispersant, 4 parts of mica, 4 parts of silica powder, 6 parts of titanium dioxide, 0.5 parts of lamp black, 2 parts of matting powder, 0.2 parts of anti-settling agent, 0.2 parts of defoaming agent, 0.2 parts of wetting and leveling agent, 0.2 parts of thickener, 2 parts of film-forming aid, and 0.7 parts of deionized water;

[0197] The topcoat curing agent comprises the following raw material components in parts by weight: 80 parts of a polyurethane curing agent and 20 parts of a solvent.

[0198] The preparation method of the primer and topcoat of the water-based insulating coating in Comparative Example 9 is the same as that in Example 1.

[0199] The primer obtained in Comparative Example 9 was mixed with the primer curing agent in the ratio of 100:20, and the topcoat was mixed with the topcoat curing agent in the ratio of 100:40, and then coated and the paint film performance test was carried out, specifically including a 100-grid adhesion performance test, an impact resistance performance test, a pull-off performance test, a flexibility test, a water resistance performance test, a high temperature and high humidity performance test, a voltage resistance performance test, a salt spray performance test, a weather resistance performance test, and a MEK resistance performance test.

[0200] Comparative Example 10

[0201] This comparative example provides a water-based insulating coating and a preparation method thereof, wherein the water-based insulating coating only includes a primer and a matching curing agent;

[0202] The primer comprises the following raw material components in parts by weight:

[0203] 30 parts of water-based epoxy emulsion A, 30 parts of water-based epoxy emulsion B, 2 parts of dispersant, 5 parts of zinc phosphate, 4 parts of mica, 4 parts of silica powder, 7 parts of titanium dioxide, 7 parts of talc, 0.5 parts of lamp black, 0.2 parts of anti-settling agent, 0.2 parts of defoaming agent, 0.2 parts of wetting and leveling agent, 0.2 parts of thickener, 2 parts of film-forming aid, 8 parts of deionized water as solvent;

[0204] The primer curing agent comprises the following raw material components in parts by weight: 40 parts of epoxy curing agent A, 40 parts of epoxy curing agent A, and 20 parts of solvent;

[0205] The preparation method of the water-based insulating coating containing only a primer comprises the following steps:

[0206] S1: Weigh part of the deionized water and put it into the tank, weigh the dispersant and defoamer and add them into the tank, and stir at a low speed of 200-300 rpm for 20 minutes;

[0207] S2: weigh the anti-settling agent, titanium dioxide, mica, silica powder, talcum powder, lamp black and zinc phosphate and put them into a tank, and stir them at a high speed of 500-700 rpm for 30 minutes;

[0208] S3: Grind the slurry to a fineness of less than 30 microns through a grinder;

[0209] S4: putting the ground slurry into an emulsion tank and stirring at a medium speed of 300-500 rpm for 30 minutes;

[0210] S5: Add water-based epoxy emulsion A and water-based epoxy emulsion B into a tank and stir at a medium speed of 300-500 rpm for 20 minutes;

[0211] S6: Put the wetting and leveling agent, ethylene glycol monobutyl ether, dipropylene glycol butyl ether, the remaining deionized water and the thickener into a tank, and stir at a medium speed of 300-500 rpm for 30 minutes to obtain the water-based insulating coating containing only the primer.

[0212] The primer obtained in Comparative Example 10 was mixed with the primer curing agent in a ratio of 100:20 and then coated, and the paint film performance tests were carried out, including a 100-grid adhesion performance test, an impact resistance performance test, a pull-off performance test, a flexibility test, a water resistance performance test, a high temperature and high humidity performance test, a voltage resistance performance test, a salt spray performance test, a weather resistance performance test, and a MEK resistance performance test.

[0213] The specific test items and test standards for paint film performance test are shown in Table 2:

[0214] Table 2: Specific test items and test standards for paint film performance test

[0215]

[0216]

[0217] The test results of the paint film properties of Example 1 and Comparative Examples 1-10 are shown in Table 3:

[0218] Table 3: Test results of paint film properties of Example 1 and Comparative Examples 1-10

[0219] Hundred Grid Attachment Impact resistance Flexibility Water resistant High temperature and humidity Voltage resistance Salt spray resistant Weather resistance MEK resistant Example 1 Level 0 OK OK OK OK OK OK OK OK Comparative Example 1 Level 0 OK OK OK OK Fail OK OK OK Comparative Example 2 Level 0 OK OK OK OK OK Fail OK Fail Comparative Example 3 Level 0 OK OK OK OK Fail OK OK OK Comparative Example 4 Level 0 OK OK OK OK Fail OK OK OK Comparative Example 5 Level 0 OK OK OK OK Fail OK OK Fail Comparative Example 6 Level 0 Fail Fail OK OK OK OK OK OK Comparative Example 7 Level 0 OK OK OK OK Fail OK OK OK Comparative Example 8 Level 0 Fail Fail OK OK OK OK OK OK Comparative Example 9 Level 0 OK OK Fail OK OK OK Fail Fail Comparative Example 10 Level 0 OK OK OK OK Fail OK Fail Fail

[0220] As shown in Table 3, the water-based insulating coating for rail transit vehicle roofs prepared in Example 1 of the present invention includes a primer and a topcoat, and has good salt spray resistance and weather resistance, as well as good voltage resistance, insulation and electrical breakdown resistance. It has good adhesion on aluminum alloys, good resistance to high temperature and humidity of 85°C, and adopts a water-based system with low VOC, non-flammable and non-explosive characteristics. Compared with Comparative Examples 1 and 2, the absence of adding water-based epoxy emulsion A to the primer affects the voltage resistance of the coating, and the absence of adding water-based epoxy emulsion B to the primer affects the salt spray resistance and MEK resistance of the coating; compared with Comparative Examples 3 and 4, the absence of adding mica or silicon powder to the primer affects the voltage resistance of the coating; compared with Comparative Examples 5 and 6, the absence of adding epoxy curing agent A to the primer curing agent affects the voltage resistance and MEK resistance of the coating, and the absence of adding epoxy curing agent B to the primer affects The results of the present invention show that the addition of mica and silica powder in the topcoat affects the impact resistance and flexibility of the coating; compared with Comparative Example 7, the addition of mica and silica powder in the topcoat affects the voltage resistance of the coating; compared with Comparative Example 8 and Comparative Example 9, too little addition of water-based acrylic dispersion in the topcoat affects the impact resistance and flexibility of the coating, and too much addition of water-based acrylic dispersion in the topcoat affects the water resistance, weather resistance and MEK resistance of the coating; compared with Comparative Example 10, only applying the primer without applying the topcoat results in insufficient voltage resistance, weather resistance and MEK resistance of the coating.

[0221] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A water-based insulating coating for rail transit vehicle roof, characterized in that: The water-based insulating coating comprises a primer and a topcoat and a matching curing agent; The primer comprises the following raw material components in parts by weight: 20-40 parts of water-based epoxy emulsion A, 20-40 parts of water-based epoxy emulsion B, 1-4 parts of dispersant, 3-6 parts of zinc phosphate, 3-6 parts of mica, 3-6 parts of silica powder, 5-10 parts of titanium dioxide, 5-10 parts of talc, 0.3-0.8 parts of lamp black, 0.1-0.4 parts of anti-settling agent, 0.1-0.4 parts of defoaming agent, 0.1-0.4 parts of wetting and leveling agent, 0.1-0.4 parts of thickener, 2-6 parts of film-forming aid; The primer curing agent comprises the following raw material components in parts by weight: 30-50 parts of epoxy curing agent A, 30-50 parts of epoxy curing agent B, and 10-30 parts of solvent; The topcoat comprises the following raw material components in parts by weight: 50-90 parts of water-based acrylic dispersion, 1-4 parts of dispersant, 3-6 parts of mica, 3-6 parts of silica powder, 5-10 parts of titanium dioxide, 0.3-0.8 parts of lamp black, 1-3 parts of matting powder, 0.1-0.5 parts of anti-settling agent, 0.1-0.5 parts of defoaming agent, 0.1-0.5 parts of wetting and leveling agent, 0.1-0.5 parts of thickener, 2-6 parts of film-forming aid; The topcoat curing agent comprises the following raw material components in parts by weight: 70-90 parts of a polyurethane curing agent and 10-30 parts of a solvent.

2. The water-based insulating coating for rail transit vehicle roof according to claim 1, characterized in that: The water-based insulating coating comprises a primer and a topcoat and a matching curing agent; The primer comprises the following raw material components in parts by weight: 25-35 parts of water-based epoxy emulsion A, 25-35 parts of water-based epoxy emulsion B, 2-3 parts of dispersant, 4-5 parts of zinc phosphate, 4-5 parts of mica, 4-5 parts of silica powder, 6-8 parts of titanium dioxide, 6-8 parts of talc, 0.4-0.6 parts of lamp black, 0.2-0.3 parts of anti-settling agent, 0.2-0.3 parts of defoaming agent, 0.2-0.3 parts of wetting and leveling agent, 0.2-0.3 parts of thickener, 2-4 parts of film-forming aid; The primer curing agent comprises the following raw material components in parts by weight: 35-45 parts of epoxy curing agent A, 35-45 parts of epoxy curing agent B, and 15-25 parts of solvent; The topcoat comprises the following raw material components in parts by weight: 60-80 parts of water-based acrylic dispersion, 2-3 parts of dispersant, 4-5 parts of mica, 4-5 parts of silica powder, 6-8 parts of titanium dioxide, 0.4-0.6 parts of lamp black, 2-3 parts of matting powder, 0.2-0.4 parts of anti-settling agent, 0.2-0.4 parts of defoaming agent, 0.2-0.4 parts of wetting and leveling agent, 0.2-0.4 parts of thickener, 2-4 parts of film-forming aid; The topcoat curing agent comprises the following raw material components in parts by weight: 75-85 parts of a polyurethane curing agent and 15-25 parts of a solvent.

3. The water-based insulating coating for rail transit vehicle roof according to claim 1, characterized in that: The water-based insulating coating comprises a primer and a topcoat and a matching curing agent; The primer comprises the following raw material components in parts by weight: 30 parts of water-based epoxy emulsion A, 30 parts of water-based epoxy emulsion B, 2 parts of dispersant, 5 parts of zinc phosphate, 4 parts of mica, 4 parts of silica powder, 7 parts of titanium dioxide, 7 parts of talc, 0.5 parts of lamp black, 0.2 parts of anti-settling agent, 0.2 parts of defoaming agent, 0.2 parts of wetting and leveling agent, 0.2 parts of thickener, 2 parts of film-forming aid; The primer curing agent comprises the following raw material components in parts by weight: 40 parts of epoxy curing agent A, 40 parts of epoxy curing agent B, and 20 parts of solvent; The topcoat comprises the following raw material components in parts by weight: 70 parts of water-based acrylic dispersion, 2 parts of dispersant, 4 parts of mica, 4 parts of silica powder, 7 parts of titanium dioxide, 0.5 parts of lamp black, 3 parts of matting powder, 0.3 parts of anti-settling agent, 0.3 parts of defoaming agent, 0.3 parts of wetting and leveling agent, 0.3 parts of thickener, 2 parts of film-forming aid; The topcoat curing agent comprises the following raw material components in parts by weight: 80 parts of a polyurethane curing agent and 20 parts of a solvent.

4. The water-based insulating coating for rail transit vehicle roof according to claim 1, characterized in that: The water-based epoxy emulsion A is a water-based epoxy emulsion with low epoxy equivalent; the water-based epoxy emulsion B is a water-based epoxy emulsion with high epoxy equivalent; and the solid content of the water-based acrylic dispersion is 30-50%.

5. The water-based insulating coating for rail transit vehicle roof according to claim 1, characterized in that: The epoxy curing agent A is a polyamide curing agent with low active hydrogen equivalent; and the epoxy curing agent B is a polyamide curing agent with high active hydrogen equivalent.

6. The water-based insulating coating for rail transit vehicle roof according to claim 1, characterized in that: The polyurethane curing agent is HDI isocyanate curing agent.

7. The water-based insulating coating for rail transit vehicle roof according to claim 1, characterized in that: The mica is 800 mesh wind-selected mica, the silicon micropowder is ultrafine silicon micropowder, and the zinc phosphate is 800 mesh water-based special zinc phosphate.

8. The water-based insulating coating for rail transit vehicle roof according to claim 1, characterized in that: The film-forming aid is prepared by mixing ethylene glycol monobutyl ether and dipropylene glycol butyl ether in a mass ratio of 1:(1-2), and the solvent is propylene glycol diacetate.

9. The method for preparing the water-based insulating coating for rail transit vehicle roof according to claim 1, characterized in that: The preparation method of the water-based insulating coating comprises the following steps: (1) preparing a primer: adding a dispersant, a defoamer, an anti-settling agent, titanium dioxide, mica powder, silica powder, talcum powder, lamp black, and zinc phosphate to water in sequence, stirring and grinding, adding water-based epoxy emulsion A, water-based epoxy emulsion B, a wetting and leveling agent, a film-forming aid, and a thickener to the ground slurry, and adding deionized water to obtain a primer; (2) Preparation of topcoat: Add dispersant, defoamer, anti-settling agent, titanium dioxide, mica powder, silica powder and lamp black to water in sequence, stir and grind evenly, add water-based acrylic dispersion, wetting and leveling agent, film-forming aid, matting powder and thickener to the ground slurry, add deionized water to obtain topcoat.

10. The use of a water-based insulating coating for a rail transit vehicle roof as claimed in claim 1, characterized in that: The water-based insulating coating is used for coating the roof surface of rail transit vehicles.

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