Crocodile pattern alloy baked paint and its preparation method and construction method

Abstract

The present application relates to the technical field of paint, in particular to a kind of crocodile pattern surface alloy baking varnish and its preparation method and construction method.The present application is through the synergistic compounding of cellulose acetate butyrate liquid, flatting powder, primer diluent, topcoat diluent, form the characteristic imitation crocodile skin decoration, with the original performance of high temperature baking varnish, high hardness, excellent wear resistance, good salt fog and hand sweat resistance, the crocodile skin formed at the same time has concave-convex lines and can have the effect of anti-slip hand.The raw materials used are all qualified for environmental protection testing, reaching the standard of children's toys.

Description

Technical Field

[0001] This invention relates to the field of coating technology, specifically to a high-temperature resistant alloy baking paint with an imitation crocodile pattern and its preparation and application methods. Background Technology

[0002] Currently, there are many types of high-temperature baked paints on the market, such as sand texture paint, wrinkle paint, and orange peel paint. As people pay more attention to the environmental friendliness and safety of everyday items, and because adults may indirectly come into contact with paint surfaces through their fingers, potentially exposing food and children to the paint, the demand for green coatings is becoming increasingly urgent. Furthermore, the aesthetic appeal of the surface is also an important factor for consumers. Current technologies often involve a long application interval between the primer and topcoat, and it is difficult to create a single, uniformly textured paint surface. Summary of the Invention

[0003] In view of this, the present invention provides a high-temperature resistant imitation crocodile pattern alloy baking paint coating and its preparation method and application method.

[0004] The technical solution of this invention is as follows:

[0005] A crocodile-patterned alloy baking paint coating, characterized in that it comprises a primer and a topcoat, wherein the primer comprises the following components by weight: 52-75 parts thermosetting acrylic resin, 21-39 parts benzoamino resin, 3-12 parts blocked isocyanate, 0.1-0.5 parts leveling agent, 2-8 parts n-butanol, and 3-15 parts nano-color paste.

[0006] The topcoat comprises the following components by weight: 28-52 parts sec-butyl acetate, 4-12 parts cellulose acetate butyrate, 0.5-2 parts wax powder, 6-13 parts matting agent, 7-15 parts cyclohexanone, 15-42 parts methyl ethyl ketone, and 3-15 parts nano-pigment.

[0007] Furthermore, the primer comprises the following components by weight: 60-70 parts thermosetting acrylic resin, 25-35 parts benzoamino resin, 5-8 parts blocked isocyanate, 0.15-0.3 parts leveling agent, 3-5 parts n-butanol, and 7-10 parts nano-color paste.

[0008] Furthermore, the topcoat comprises the following components by weight: 35-41 parts sec-butyl acetate, 6-8 parts cellulose acetate butyrate, 0.8-1.2 parts wax powder, 7-11 parts matting agent, 8-12 parts cyclohexanone, 22-30 parts methyl ethyl ketone, and 7-10 parts nano-pigment.

[0009] In particular, each component in this invention needs to be tested for environmental standards such as heavy metals and plasticizers to ensure that the product supply process is subject to environmental monitoring and meets the environmental standards for children's toys.

[0010] Furthermore, it also includes a primer thinner, which comprises the following parts by weight: 82-105 parts ethyl acetate and 3-10 parts cyclohexanone.

[0011] Furthermore, the primer thinner comprises the following components by weight: 95 parts ethyl acetate and 5 parts cyclohexanone.

[0012] In this invention, ethyl acetate and cyclohexanone are used in a synergistic compound as a primer thinner. After diluting the primer components, the mixture is sprayed onto the surface of the alloy workpiece, allowing the paint film to air dry at room temperature. The solvent evaporates quickly, and the construction operation has a short waiting time before the topcoat components can be sprayed. This solves the problem of slow surface drying of baking paint and provides support for large-scale production in the factory.

[0013] Furthermore, it also includes a topcoat thinner, which comprises the following parts by weight: 28-45 parts sec-butyl acetate, 8-18 parts cyclohexanone, and 48-69 parts acetone.

[0014] Furthermore, the topcoat thinner comprises the following components by weight: 35 parts sec-butyl acetate, 10 parts cyclohexanone, and 55 parts acetone.

[0015] In this invention, acetone, cyclohexanone, and sec-butyl ester are used as a synergistic compound as a topcoat thinner. This thinner contains ketone solvents, which have strong dissolving power and fast drying speed. During the drying process, due to the fast drying of acetone, the paint film after spraying changes the surface of the paint film, which should be smooth and flat, during the self-drying process at room temperature in about 1 minute. This shrinks the paint oil components of the topcoat and produces a textured effect, thus achieving the textured effect and the appearance of the paint film with a crocodile skin texture.

[0016] Furthermore, the cellulose acetate butyrate grade includes at least one of the following: CAB-381-0.5, CAB-381-2, CAB-381-20, and CAB-551-0.01. Specifically:

[0017] CAB-381-0.5: Medium butyryl content, low viscosity, suitable for applications with low application viscosity and high solids content;

[0018] CAB-381-2: Good miscibility, excellent flexibility, good weather resistance and UV resistance, high viscosity;

[0019] CAB-551-0.01: High butyryl content, low viscosity, soluble in monomers such as styrene and methyl methacrylate, and has better tolerance to diluents such as aliphatic and aromatic hydrocarbons.

[0020] CAB-381-20: High butyryl content, high viscosity, with good comprehensive properties such as solubility, compatibility, water resistance, excellent surface hardness and high coating strength.

[0021] Cellulose acetate butyrate plays the following roles in paints and topcoats: improving leveling properties: reducing paint film defects and improving the uniformity and aesthetics of the coating film; directional alignment of metallic pigments: optimizing the amount of aluminum powder used, reducing costs, and enhancing metallic luster; improving weather resistance: preventing yellowing / loss of gloss and enhancing the outdoor durability of the paint; shortening drying time: improving production efficiency and accelerating construction progress; enhancing abrasion resistance and color stability: increasing the toughness of plastic coatings and extending their service life.

[0022] Specifically, this invention is applied to the fields of metal door lock accessories, ceramic handicrafts, electrical switches and sockets (including bakelite and plastic), alloy toy car models, hardware toys, and electrical metal accessories.

[0023] In this invention, the raw materials used are formulated to meet the standards for children's toys exported to various countries. For example, PAHs meet the Class II standards for children's toys, heavy metals meet the EN71-3-2019 standard, and phthalates meet export standards, RoHS, US F963, and Chinese national standards.

[0024] In this invention, the synergistic compounding of thermosetting acrylic resin and cellulose acetate butyrate results in a paint film that is resistant to high temperatures (up to 160°C) and does not yellow. The use of phenylamino resin and blocked isocyanate in the cross-linking reaction of the thermosetting acrylic resin effectively improves the paint film's water resistance, sweat resistance, and salt spray resistance. In particular, this invention can create a decorative pattern resembling crocodile skin while effectively protecting the surface of metal parts from oxidation. Testing shows that the paint film formed by this invention achieves a Mitsubishi pencil hardness of H, withstands prolonged baking at 100°C without damage, and does not blister or peel after 96 hours of testing in a high-temperature and high-humidity environment (60°C, 90% humidity).

[0025] Through the synergistic compounding of the components of this invention, combined with specific construction techniques, the varnish can achieve a matte gloss surface effect, presenting a rich texture appearance ranging from large tortoise shell patterns to small cotton-like patterns, giving a "tactile feel," with unique texture effects and excellent physical and mechanical properties, satisfying consumers' pursuit of high-quality varnish.

[0026] A method for preparing an alloy baking paint coating with an imitation crocodile pattern includes the preparation of a primer and the preparation of a topcoat;

[0027] The preparation method of the primer includes the following:

[0028] Add thermosetting acrylic resin, benzoamino resin, blocked isocyanate, and leveling agent in sequence, and gradually increase the rotation speed to 800-1000 RPM and disperse for 10-18 minutes until the fineness / cleanliness is ≥6H / A.

[0029] Add n-butanol to adjust viscosity;

[0030] Add nano-colorant to adjust the color;

[0031] The preparation method of the topcoat includes the following:

[0032] Add sec-butyl acetate, cellulose acetate butyrate, wax powder, matting agent, and cyclohexanone in sequence, and gradually increase the rotation speed to 600-1000 RPM for 15-25 minutes. Stop the process when the fineness / cleanliness is ≥4H / A.

[0033] Add methyl ethyl ketone (MEK) to adjust viscosity;

[0034] Add nano pigments to adjust the color.

[0035] Furthermore, the preparation method also includes the preparation of a primer thinner and a topcoat thinner;

[0036] The preparation method of the primer thinner includes the following: ethyl acetate and cyclohexanone are mixed separately and dispersed at a speed of 500-800 RPM for 30-60 seconds;

[0037] The preparation method of the topcoat thinner includes the following: mixing sec-butyl acetate, cyclohexanone, and acetone separately, and dispersing at a speed of 500-800 RPM for 30-60 seconds.

[0038] A method for applying an alloy baking paint with an imitation crocodile pattern, comprising primer application and topcoat application;

[0039] The primer application includes the following:

[0040] Prepare the substrate and pre-treat the surface; the substrate surface must be clean. If it is a metal substrate, it should be degreased, cleaned and dried first.

[0041] Dilution treatment: Dilute according to the volume ratio of primer to primer thinner of 1:0.5-0.7; When used in conjunction with the primer thinner of this invention, the construction operation in production is easier, or when using automatic mechanical spraying, the setting of the spraying machine is simpler to adjust to the required effect, and the pass rate of the sprayed workpiece is improved.

[0042] Spraying application: Control the viscosity to 10-25s (NK-2 viscosity cup), spray a 20-25um thick paint film evenly, and after 10-20 minutes, proceed to the second topcoat process.

[0043] The topcoat application includes the following:

[0044] Dilution treatment: Dilute the topcoat to the topcoat thinner at a volume ratio of 1:0.7-1; when used in conjunction with the topcoat thinner of this invention, the construction operation in production is easier, or when using automatic mechanical spraying, the setting of the spraying machine is simpler to adjust to the required effect, and the pass rate of the sprayed workpiece is improved.

[0045] Spraying application: After the primer is sprayed, let it air dry for 10-20 minutes, then spray the topcoat components, controlling the viscosity to 10-25s (NK-2 viscosity cup). Use wet-on-wet application to ensure that the primer and topcoat films are completely bonded together, and to provide conditions for the subsequent film to shrink, crack, and develop uneven textures.

[0046] In particular, the actual construction should be carried out according to the size of the alloy workpiece area to be sprayed, with the effect determined by the designer as a reference. If a pattern with obvious concave and convex textures is required, a higher construction viscosity should be used, that is, less thinner should be added.

[0047] Drying process: First, dry at 100-120℃ for 10-20 minutes to prevent the paint film from bubbling; then raise the temperature to 145-165℃ and dry for 25-40 minutes to thoroughly bake the paint film, which will result in a crocodile skin texture effect paint film with qualified appearance and performance.

[0048] During the spraying process, the topcoat is applied in a single coat to a film thickness of 20-30µm. Re-spraying is not permitted as it will affect the formation of the textured effect due to shrinkage. The desired degree of shrinkage and cracking should be achieved, with the film thickness sufficient to create the planned crocodile skin texture. A thicker coat will produce a more pronounced textured effect. For optimal surface texture formation, the spray gun nozzle diameter should be controlled between 2.5-3.5mm.

[0049] It also includes gloss and matte adjustment, including using different colors of varnish for color matching or spraying varnishes with different gloss levels to adjust the desired gloss and matte effect.

[0050] In this invention, through extensive creative experiments, it was discovered that due to poor surface treatment of matte powder, its water / solvent absorption is very high. When the solvent evaporates, it easily causes the paint film to crack. Cellulose acetate butyrate is also a high-viscosity raw material with a high water / solvent absorption. When these two raw materials are combined in the same formula, and an appropriate fast-drying strong solvent is added, the solvent evaporation during the drying process will shrink the paint film, resulting in a textured effect. By setting the primer component and topcoat component with matching thinners in this invention, after adding thinner to their respective formulations, the overall solubility and evaporation rate of the paint are coordinated with the application process. After the final application and spraying, the solvent evaporates, and during the drying process, the paint film surface, which should be smooth and even, is altered to produce the desired textured effect.

[0051] In addition, the content of matting agent in the topcoat is also very important. When the content is too low, the shrinkage of the paint film is insufficient, and no textured pattern is formed or the textured pattern lacks texture. When the content is too high, the paint film surface will 'powder'. After drying, the paint film can be easily scratched with a fingernail. The formation of textured pattern is uncontrolled, and an aesthetically pleasing crocodile skin texture effect cannot be formed. Furthermore, the basic performance tests such as the hardness of the paint film are not up to standard, the 100℃ boiling water test is not up to standard, and the hand sweat resistance test is not up to standard.

[0052] In this invention, the amount of matting powder plays an important role in the formulation. When the amount of matting powder is low, the shrinkage of the paint film is very low, and the surface of the paint film after spraying is a smooth, fully matte paint film without any crocodile skin texture effect, or only a semi-matte, flat paint film appears after spraying, without any unevenness.

[0053] When the amount of matting powder is high, the crocodile skin texture effect lacks hardness and has poor adhesion after the paint dries. At the same time, the topcoat also becomes severely thickened, and the viscosity is out of control. If the material is not completely dispersed during production and mixing, the resulting paint is difficult to apply and spray, making it difficult to achieve a qualified crocodile skin texture effect.

[0054] This invention utilizes the synergistic compounding of cellulose acetate butyrate solution, matting powder, primer thinner, and topcoat thinner to create a distinctive crocodile-skin texture decoration. It retains the original properties of high-temperature baked enamel, exhibiting high hardness, excellent wear resistance, and good resistance to hand sweat and salt spray. The resulting crocodile-skin texture also provides a non-slip grip. All raw materials used have passed environmental testing and meet children's toy-grade standards.

[0055] The beneficial effects of this invention are as follows:

[0056] 1. Forms an attractive imitation crocodile skin textured paint film on the surface of the workpiece, providing a non-slip, textured effect.

[0057] 2. The paint film has the basic properties that ordinary metal baking paint should have, such as qualified adhesion, wear resistance and high hardness, high temperature and high humidity resistance, and alcohol scrubbing resistance.

[0058] 3. The paint film meets the environmental protection requirements for children's toys, such as passing the standards for heavy metals, plasticizers, and PAHS (polycyclic aromatic hydrocarbons);

[0059] 4. The application interval between primer and topcoat is effectively shortened, improving production efficiency and providing a foundation for large-scale production. Detailed Implementation

[0060] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not limit the scope of protection of the invention. Example 1

[0061] A crocodile-patterned alloy baking paint coating, characterized in that it comprises a primer and a topcoat, wherein the primer comprises the following components by weight: 67 parts thermosetting acrylic resin, 33 parts benzoamino resin, 6 parts blocked isocyanate, 0.2 parts leveling agent, 3.8 parts n-butanol, and 10 parts nano-color paste.

[0062] The topcoat comprises the following components by weight: 41 parts sec-butyl acetate, 7.5 parts cellulose acetate butyrate, 1 part wax powder, 10 parts matting agent, 10 parts cyclohexanone, 20.5 parts methyl ethyl ketone, and 10 parts nano-color paste.

[0063] In this embodiment, the thermosetting acrylic resin used is LM-3050 from Langma Chemical, the phenylamino resin used is K444HB from Shunying Company, the blocked isocyanate used is K3142HA from Shunying Company, the leveling agent used is BYK313 from BYK Company, the cellulose acetate butyrate used is Eastman Company from the United States, and the wax powder used is LANCO 1400SF from Lubrizol Company from Germany.

[0064] It also includes a primer thinner, which comprises the following components by weight: 95 parts ethyl acetate and 5 parts cyclohexanone.

[0065] It also includes a topcoat thinner, which comprises the following components by weight: 35 parts sec-butyl acetate, 10 parts cyclohexanone, and 55 parts acetone.

[0066] The cellulose acetate butyrate is designated as CAB-381-20. Example 2

[0067] A crocodile-patterned alloy baking paint coating, characterized in that it comprises a primer and a topcoat, wherein the primer comprises the following components by weight: 54 parts thermosetting acrylic resin, 24 parts benzoamino resin, 5 parts blocked isocyanate, 0.2 parts leveling agent, 3 parts n-butanol, and 5 parts nano-color paste.

[0068] The topcoat comprises the following components by weight: 31 parts sec-butyl acetate, 5 parts cellulose acetate butyrate, 0.8 parts wax powder, 7 parts matting agent, 9 parts cyclohexanone, 16 parts methyl ethyl ketone, and 5 parts nano-color paste.

[0069] It also includes a primer thinner, which comprises the following components by weight: 84 parts ethyl acetate and 4 parts cyclohexanone.

[0070] It also includes a topcoat thinner, which comprises the following components by weight: 30 parts sec-butyl acetate, 10 parts cyclohexanone, and 51 parts acetone.

[0071] The cellulose acetate butyrate is a combination of CAB-381-2 and CAB-381-20, with a mass ratio of 1:5. Example 3

[0072] A crocodile-patterned alloy baking paint coating, characterized in that it comprises a primer and a topcoat, wherein the primer comprises the following components by weight: 72 parts thermosetting acrylic resin, 36 parts benzoamino resin, 11 parts blocked isocyanate, 0.4 parts leveling agent, 7 parts n-butanol, and 14 parts nano-color paste.

[0073] The topcoat comprises the following components by weight: 50 parts sec-butyl acetate, 10 parts cellulose acetate butyrate, 1.7 parts wax powder, 12 parts matting agent, 13 parts cyclohexanone, 38 parts methyl ethyl ketone, and 14 parts nano-color paste.

[0074] It also includes a primer thinner, which comprises the following components by weight: 101 parts ethyl acetate and 9 parts cyclohexanone.

[0075] It also includes a topcoat thinner, which comprises the following components by weight: 43 parts sec-butyl acetate, 16 parts cyclohexanone, and 63 parts acetone.

[0076] The cellulose acetate butyrate is a combination of CAB-381-0.5 and CAB-381-20, with a mass ratio of 1:9. Example 4

[0077] A crocodile-patterned alloy baking paint coating, characterized in that it comprises a primer and a topcoat, wherein the primer comprises the following components by weight: 60 parts thermosetting acrylic resin, 25 parts benzoamino resin, 5 parts blocked isocyanate, 0.15 parts leveling agent, 3 parts n-butanol, and 7 parts nano-color paste.

[0078] The topcoat comprises the following components by weight: 35 parts sec-butyl acetate, 6 parts cellulose acetate butyrate, 0.8 parts wax powder, 7 parts matting agent, 8 parts cyclohexanone, 22 parts methyl ethyl ketone, and 7 parts nano-color paste.

[0079] It also includes a primer thinner, which comprises the following components by weight: 82 parts ethyl acetate and 3 parts cyclohexanone.

[0080] It also includes a topcoat thinner, which comprises the following components by weight: 28 parts sec-butyl acetate, 8 parts cyclohexanone, and 48 parts acetone.

[0081] The cellulose acetate butyrate is a combination of CAB-381-20 and CAB-551-0.01, with a mass ratio of 10:1. Example 5

[0082] A crocodile-patterned alloy baking paint coating, characterized in that it comprises a primer and a topcoat, wherein the primer comprises the following components by weight: 70 parts thermosetting acrylic resin, 35 parts benzoamino resin, 8 parts blocked isocyanate, 0.3 parts leveling agent, 5 parts n-butanol, and 10 parts nano-color paste.

[0083] The topcoat comprises the following components by weight: 41 parts sec-butyl acetate, 8 parts cellulose acetate butyrate, 1.2 parts wax powder, 11 parts matting agent, 12 parts cyclohexanone, 30 parts methyl ethyl ketone, and 10 parts nano-color paste.

[0084] It also includes a primer thinner, which comprises the following components by weight: 95 parts ethyl acetate and 6 parts cyclohexanone.

[0085] It also includes a topcoat thinner, which comprises the following components by weight: 36 parts sec-butyl acetate, 15 parts cyclohexanone, and 55 parts acetone.

[0086] The cellulose acetate butyrate is designated as CAB-381-2. Example 6

[0087] A crocodile-patterned alloy baking paint coating, characterized in that it comprises a primer and a topcoat, wherein the primer comprises the following components by weight: 67 parts thermosetting acrylic resin, 33 parts benzoamino resin, 6 parts blocked isocyanate, 0.2 parts leveling agent, 3.8 parts n-butanol, and 10 parts nano-color paste.

[0088] The topcoat comprises the following components by weight: 41 parts sec-butyl acetate, 7.5 parts cellulose acetate butyrate, 1 part wax powder, 10 parts matting agent, 10 parts cyclohexanone, 20.5 parts methyl ethyl ketone, and 10 parts nano-color paste.

[0089] In this embodiment, the thermosetting acrylic resin used is LM-3050 from Langma Chemical, the phenylamino resin used is K444HB from Shunying Company, the blocked isocyanate used is K3142HA from Shunying Company, the leveling agent used is BYK313 from BYK Company, the cellulose acetate butyrate used is Eastman Company from the United States, and the wax powder used is LANCO 1400SF from Lubrizol Company from Germany.

[0090] It also includes a primer thinner, which comprises the following components by weight: 95 parts ethyl acetate and 5 parts cyclohexanone.

[0091] It also includes a topcoat thinner, which comprises the following components by weight: 35 parts sec-butyl acetate, 10 parts cyclohexanone, and 55 parts acetone.

[0092] The cellulose acetate butyrate is designated as CAB-381-2. Example 7

[0093] A method for preparing an alloy baking paint coating with an imitation crocodile pattern includes the preparation of a primer and the preparation of a topcoat;

[0094] The preparation method of the primer includes the following:

[0095] Add thermosetting acrylic resin, benzoamino resin, blocked isocyanate, and leveling agent in sequence, and gradually increase the rotation speed to 900 RPM and disperse for 15 minutes until the fineness / cleanliness is ≥6H / A.

[0096] Add n-butanol to adjust viscosity;

[0097] Add nano-colorant to adjust the color;

[0098] The preparation method of the topcoat includes the following:

[0099] Add sec-butyl acetate, cellulose acetate butyrate, wax powder, matting agent, and cyclohexanone in sequence, and gradually increase the speed to 900 RPM to disperse for 20 minutes until the fineness / cleanliness is ≥4H / A.

[0100] Add methyl ethyl ketone (MEK) to adjust viscosity;

[0101] Add nano pigments to adjust the color.

[0102] Furthermore, the preparation method also includes the preparation of a primer thinner and a topcoat thinner;

[0103] The preparation method of the primer thinner includes the following: ethyl acetate and cyclohexanone are mixed separately and dispersed at a speed of 600 RPM for 45 seconds;

[0104] The preparation method of the topcoat thinner includes the following: mixing sec-butyl acetate, cyclohexanone, and acetone separately, and dispersing at a speed of 600 RPM for 45 seconds. Example 8

[0105] A method for preparing an alloy baking paint coating with an imitation crocodile pattern includes the preparation of a primer and the preparation of a topcoat;

[0106] The preparation method of the primer includes the following:

[0107] Add thermosetting acrylic resin, benzoamino resin, blocked isocyanate, and leveling agent in sequence, and gradually increase the rotation speed to 800 RPM and disperse for 18 minutes until the fineness / cleanliness is ≥6H / A.

[0108] Add n-butanol to adjust viscosity;

[0109] Add nano-colorant to adjust the color;

[0110] The preparation method of the topcoat includes the following:

[0111] Add sec-butyl acetate, cellulose acetate butyrate, wax powder, matting agent, and cyclohexanone in sequence, and gradually increase the speed to 600 RPM to disperse for 25 min until the fineness / cleanliness is ≥4H / A.

[0112] Add methyl ethyl ketone (MEK) to adjust viscosity;

[0113] Add nano pigments to adjust the color.

[0114] Furthermore, the preparation method also includes the preparation of a primer thinner and a topcoat thinner;

[0115] The preparation method of the primer thinner includes the following: ethyl acetate and cyclohexanone are mixed separately and dispersed at a speed of 500 RPM for 60 seconds;

[0116] The preparation method of the topcoat thinner includes the following: mixing sec-butyl acetate, cyclohexanone, and acetone separately, and dispersing at a speed of 500 RPM for 60 seconds. Example 9

[0117] A method for preparing an alloy baking paint coating with an imitation crocodile pattern includes the preparation of a primer and the preparation of a topcoat;

[0118] The preparation method of the primer includes the following:

[0119] Add thermosetting acrylic resin, benzoamino resin, blocked isocyanate, and leveling agent in sequence, and gradually increase the rotation speed to 1000 RPM and disperse for 10 minutes until the fineness / cleanliness is ≥6H / A.

[0120] Add n-butanol to adjust viscosity;

[0121] Add nano-colorant to adjust the color;

[0122] The preparation method of the topcoat includes the following:

[0123] Add sec-butyl acetate, cellulose acetate butyrate, wax powder, matting agent, and cyclohexanone in sequence, and gradually increase the speed by 1000 RPM for 15 min, until the fineness / cleanliness is ≥4H / A, then stop.

[0124] Add methyl ethyl ketone (MEK) to adjust viscosity;

[0125] Add nano pigments to adjust the color.

[0126] Furthermore, the preparation method also includes the preparation of a primer thinner and a topcoat thinner;

[0127] The preparation method of the primer thinner includes the following: ethyl acetate and cyclohexanone are mixed separately and dispersed at 800 RPM for 30 seconds;

[0128] The preparation method of the topcoat thinner includes the following: mixing sec-butyl acetate, cyclohexanone, and acetone separately, and dispersing at 800 RPM for 30 seconds. Example 10

[0129] A method for applying an alloy baking paint with an imitation crocodile pattern, comprising primer application and topcoat application;

[0130] The primer application includes the following:

[0131] Prepare the substrate and pre-treat the surface;

[0132] Dilution treatment: Dilute the primer to primer thinner at a volume ratio of 1:0.6;

[0133] Spraying application: Control the viscosity to 15s, spray a 22um thick paint film evenly, and after 15 minutes, proceed to the second topcoat process.

[0134] The topcoat application includes the following:

[0135] Dilution: Dilute the topcoat to the topcoat thinner at a volume ratio of 1:0.8;

[0136] Spraying application: After the primer is sprayed and allowed to dry for 15 minutes, the topcoat components are sprayed, with the viscosity controlled at 18 seconds, using a wet-on-wet application method.

[0137] Drying process: First, dry at 110℃ for 15 minutes, then increase the temperature to 155℃ and dry for 30 minutes.

[0138] During the spraying process, the topcoat is sprayed in one go to a film thickness of 25µm.

[0139] During the spraying process, the nozzle diameter of the spray gun is controlled at 3mm.

[0140] It also includes adjusting the gloss level, including using different colored varnishes for color matching or spraying varnishes with different gloss levels. Example 11

[0141] A method for applying an alloy baking paint with an imitation crocodile pattern, comprising primer application and topcoat application;

[0142] The primer application includes the following:

[0143] Prepare the substrate and pre-treat the surface;

[0144] Dilution: Dilute the primer to primer thinner at a volume ratio of 1:0.5.

[0145] Spraying application: Control the viscosity to 10-25s, spray a 25um thick paint film evenly, and after 20 minutes, proceed to the second topcoat process.

[0146] The topcoat application includes the following:

[0147] Dilution: Dilute the topcoat to the topcoat thinner at a volume ratio of 1:0.7;

[0148] Spraying application: After the primer is sprayed and allowed to dry for 20 minutes, the topcoat components are sprayed, with the viscosity controlled at 10-25 seconds, using a wet-on-wet application method;

[0149] Drying process: First, dry at 100℃ for 20 minutes, then increase the temperature to 145℃ and dry for 35 minutes.

[0150] During the spraying process, the topcoat is sprayed in one go to a film thickness of 20µm.

[0151] During the spraying process, the nozzle diameter of the spray gun is controlled at 3.5mm.

[0152] It also includes adjusting the gloss level, including using different colored varnishes for color matching or spraying varnishes with different gloss levels. Example 12

[0153] A method for applying an alloy baking paint with an imitation crocodile pattern, comprising primer application and topcoat application;

[0154] The primer application includes the following:

[0155] Prepare the substrate and pre-treat the surface;

[0156] Dilution treatment: Dilute the primer to primer thinner at a volume ratio of 1:0.7;

[0157] Spraying application: Control the viscosity to 10-25s, spray a 20um thick paint film evenly, and after 10 minutes, proceed to the second topcoat process.

[0158] The topcoat application includes the following:

[0159] Dilution: Dilute the topcoat to the topcoat thinner at a volume ratio of 1:1;

[0160] Spraying application: After the primer is sprayed and allowed to dry for 10 minutes, the topcoat components are sprayed, with the viscosity controlled at 10-25 seconds, using a wet-on-wet application method.

[0161] Drying process: First, dry at 120℃ for 10 minutes, then increase the temperature to 165℃ and dry for 25 minutes.

[0162] During the spraying process, the topcoat is sprayed in one go to a film thickness of 30µm.

[0163] During the spraying process, the nozzle diameter of the spray gun is controlled at 2.5mm.

[0164] It also includes adjusting the gloss level, including using different colored varnishes for color matching or spraying varnishes with different gloss levels.

[0165] Comparative Example 1

[0166] This comparative example provides an alloy baking paint coating with the same crocodile pattern as Example 1. The difference is that high-speed nitrocellulose is used instead of cellulose acetate butyrate in the topcoat. Nitrocellulose cannot withstand temperatures above 100°C. After baking at high temperature for 5 minutes, it will lose its gloss and the paint film will turn yellow. Therefore, it cannot be used in this formulation system.

[0167] Comparative Example 2

[0168] This comparative example provides an alloy baking paint coating with an imitation crocodile pattern, identical to that of Example 1. The difference lies in the use of different primer and topcoat thinners compared to Example 1. Both are formulated with the following weight proportions: xylene 25%, butanol 10%, cyclohexanone 15%, and butyl acetate 50%.

[0169] In this comparative example, when this thinner formula is used as a primer thinner, the solvent evaporates slowly, resulting in slower drying and impacting application efficiency. After spraying the primer, a drying time of over one hour is required before applying the topcoat, affecting the needs of large-scale production. When used as a topcoat thinner, since the topcoat requires a strong, fast-drying thinner to achieve the desired crocodile skin texture, this formula is too slow-drying. During application, some areas may lack texture or the crocodile skin effect may not be achieved as required.

[0170] Comparative Example 3

[0171] This comparative example provides an alloy baking paint coating with an imitation crocodile pattern, identical to that of Example 1. The difference lies in the primer and topcoat thinners, which are different from those in Example 1. Their formulations use the following weight proportions: xylene 90%, cyclohexanone 10%.

[0172] In this comparative example, when this thinner formulation is used as a primer thinner, the slow volatility of xylene and cyclohexanone affects application efficiency. In spring and winter, it can cause quality issues such as "sagging and edge accumulation." After applying the primer, it requires waiting more than half a day before applying the topcoat, affecting the timely application of the topcoat. When used as a topcoat thinner, since the topcoat requires a strong, fast-drying thinner to achieve the desired crocodile-skin texture effect, this slow-drying formulation will not produce the desired texture during application.

[0173] Comparative Example 4

[0174] This comparative example provides an alloy baking paint coating with an imitation crocodile pattern surface, identical to that of Example 1. The difference lies in the use of different primer and topcoat thinners compared to Example 1. The primer / topcoat thinner formulations are as follows: xylene 90%, butyl acetate 10%.

[0175] In this comparative example, when this thinner formulation is used as a primer thinner, the xylene-based thinner has very slow volatility. In spring and winter, it can cause quality issues such as "sagging and edge accumulation." After applying the primer, it requires waiting at least half a day before applying the topcoat, affecting the timeliness of topcoat application. When used as a topcoat thinner, since the topcoat requires a strong, fast-drying thinner to achieve the desired crocodile-skin texture, this formulation lacks sufficient dissolving power and is slow-drying. After application, the texture may not form, or only a small texture may appear in a specific location.

[0176] Experimental effect test

[0177] Performance testing

[0178] Using the components of Example 1, Example 6, and Comparative Example 1, the preparation method of Example 7, and the application process of Example 10, the paint surface was obtained and its performance was tested. The results are shown in the table below:

[0179] project Example 1 Example 6 Comparative Example 1 Required standard value Creates a crocodile skin texture effect Finished product qualification rate: 97% The manual spraying process is difficult to operate, resulting in a 10% decrease in the finished product qualification rate. Furthermore, when using automated mechanical spraying equipment, the difficulty of adjusting the spray gun increases by 30%. Finished product qualification rate: 97% Refer to the provided color swatches Appearance Finished product qualification rate: 97% When the requirement is a large embossed texture effect, the finished product pass rate decreases by 20%, and when the requirement is a small embossed texture effect, the finished product pass rate also decreases by 10%. The paint film turns burnt yellow during the high-temperature baking process. Refer to the provided color swatches Adhesion 100% qualified 65% Adhesion test on paint film surface: First, make 100 cross grids with a knife using a 1*1mm grid, and then firmly adhere a layer of 3M tape (600#) to the surface of the cross grids. Then, quickly remove the tape at a 90-degree angle. Standard: No signs of paint peeling or degradation. hardness H H F Hardness test: Apply 1kg force to the coated surface with a triangular pencil, then push the pencil away from the operator with a stroke of 20mm. Repeat 4 times at adjacent positions. No scratches were found on the surface. Resistant to hand sweat qualified qualified Very bad Immerse the parts in the following hand sweat solution for 48 hours (hand sweat solution: a weak acid solution provided). Standard: Cracking, discoloration, staining, or blistering is not permitted. Resistant to alcohol clearness qualified qualified Difference Using a soft white cloth (100% cotton), perform an alcohol test: immerse the cloth in 75% alcohol, then rub the test surface with a 1kg load for 15 seconds. Standard: No signs of paint peeling or degradation. Acetone resistance qualified qualified Difference Using a soft white cloth (100% cotton), soak it in acetone and then wipe the paint over 15 seconds (speed: return motion approximately one second, force 500 g ± 50 g. Standard: no signs of paint peeling or degradation). Detergent resistant qualified qualified Difference Using a soft white cloth (100% cotton), soak it in a 1:9 solution of detergent and water, then scrub the paint over 15 seconds (speed: approximately one back-and-forth motion per second, with a force of 1000g ± 200g). Standard: No signs of paint peeling or degradation. Salt spray resistance qualified qualified Very bad Place it in a salt spray tester (5% sodium chloride solution) for 48 hours; it should not show signs of rusting or oxidation. High temperature and humidity resistance qualified qualified Very bad Place it in a high-temperature, high-humidity chamber (temperature 50℃, humidity 90%) and test for 120 hours; no bubbles or mold should appear.

[0180] Comparison of crocodile skin texture effect

[0181] By using the components of Example 1 and Comparative Examples 2-4, the preparation method of Example 7, and the construction process of Example 10, the paint surface after dilution and topcoat spraying can be observed to show that: the paint film formed in Example 1 has a textured effect; the paint surface of Comparative Examples 2-4 does not have a textured effect, or a textured effect appears in some parts, while most of it is still a smooth paint film surface.

[0182] From the perspective of the finished paint film, considering the overall quality and performance of the formulation, a balanced and qualified performance across all components is required. Experimental data shows that using high-speed nitrocellulose instead of cellulose acetate butyrate in tests confirmed that nitrocellulose, when added to the formulation, has drawbacks such as poor resistance to temperatures above 100℃ and susceptibility to aging and discoloration. In contrast, the formulation using matting powder in combination with cellulose acetate butyrate does not discolor or dissolve / deteriorate at 150℃ during high-temperature baking. This demonstrates that the combination of matting powder and cellulose acetate butyrate as the main raw materials for the topcoat in this invention is the optimal combination selected through experimental comparison, ensuring the performance and quality of achieving the crocodile skin texture effect.

[0183] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

[0184] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be appropriately combined to form other embodiments that can be understood by those skilled in the art. It should be noted that technical features not described in detail in this invention can all be implemented by any existing technology in the art.

Claims

1. A crocodile-patterned alloy baking paint coating, characterized in that, It includes a primer and a topcoat, wherein the primer comprises the following components by weight: 52-75 parts thermosetting acrylic resin, 21-39 parts benzoamino resin, 3-12 parts blocked isocyanate, 0.1-0.5 parts leveling agent, 2-8 parts n-butanol, and 3-15 parts nano-color paste; The topcoat comprises the following components by weight: 28-52 parts sec-butyl acetate, 4-12 parts cellulose acetate butyrate, 0.5-2 parts wax powder, 4-16 parts matting agent, 7-15 parts cyclohexanone, 15-42 parts methyl ethyl ketone, and 3-15 parts nano-pigment. It also includes a primer thinner, which comprises the following parts by weight: 82-105 parts of ethyl acetate and 3-10 parts of cyclohexanone; It also includes a topcoat thinner, which comprises the following components by weight: 28-45 parts sec-butyl ester, 8-18 parts cyclohexanone, and 48-69 parts acetone.

2. The alligator-patterned alloy baking paint coating according to claim 1, characterized in that, The primer comprises the following components by weight: 60-70 parts thermosetting acrylic resin, 25-35 parts benzoamino resin, 5-8 parts blocked isocyanate, 0.15-0.3 parts leveling agent, 3-5 parts n-butanol, and 7-10 parts nano-color paste.

3. The alligator-patterned alloy baking paint coating according to claim 1, characterized in that, The topcoat comprises the following components by weight: 35-41 parts sec-butyl acetate, 6-8 parts cellulose acetate butyrate, 0.8-1.2 parts wax powder, 7-11 parts matting agent, 8-12 parts cyclohexanone, 22-30 parts methyl ethyl ketone, and 7-10 parts nano-pigment.

4. The crocodile-pattern alloy baking paint coating according to claim 3, wherein the cellulose acetate butyrate is of at least one of the following types: CAB-381-0.5, CAB-381-2, CAB-381-20, CAB-551-0.

01.

5. A method for preparing the alligator-patterned alloy baking paint coating as described in claim 4, characterized in that, This includes the preparation of the primer and the preparation of the topcoat; The preparation method of the primer includes the following: Add thermosetting acrylic resin, benzoamino resin, blocked isocyanate, and leveling agent in sequence, and gradually increase the rotation speed to 800-1000 RPM and disperse for 10-18 minutes until the fineness / cleanliness is ≥6H / A. Add n-butanol to adjust viscosity; Add nano-colorant to adjust the color; The preparation method of the topcoat includes the following: Add sec-butyl ester, cellulose acetate butyrate, wax powder, matting agent, and cyclohexanone in sequence, and gradually increase the rotation speed to 600-1000 RPM for 15-25 min, until the fineness / cleanliness is ≥4H / A, then stop. Add methyl ethyl ketone (MEK) to adjust viscosity; Add nano pigments to adjust the color.

6. The method for preparing the imitation crocodile-pattern alloy baking paint coating according to claim 5, characterized in that, It also includes the preparation of primer thinner and topcoat thinner; The preparation method of the primer thinner includes the following: ethyl acetate and cyclohexanone are mixed separately and dispersed at a speed of 500-800 RPM for 30-60 seconds; The preparation method of the topcoat thinner includes the following: mixing sec-butyl ester, cyclohexanone, and acetone separately, and dispersing at a speed of 500-800 RPM for 30-60 seconds.

7. A method for applying the alligator-patterned alloy baking paint according to any one of claims 1-4, characterized in that, This includes primer application and topcoat application; The primer application includes the following: Prepare the substrate and pre-treat the surface; Dilution: Dilute the primer to primer thinner at a volume ratio of 1:0.5-0.

7. Spraying application: Control the viscosity to 10-25s, spray a 20-25μm thick paint film evenly, and after 10-20 minutes, proceed to the second topcoat process; The topcoat application includes the following: Dilution: Dilute the topcoat to the topcoat thinner at a volume ratio of 1:0.7-1; Spraying application: After the primer is sprayed, allow it to air dry for 10-20 minutes, then spray the topcoat components, controlling the viscosity to 10-25 seconds, using a wet-on-wet application method; Drying process: First, dry at 100-120℃ for 10-20 minutes, then raise the temperature to 145-165℃ and dry for 25-40 minutes.

8. The application method of the imitation crocodile-pattern alloy baking paint according to claim 7, characterized in that, During the spraying process, the topcoat is sprayed in one go to achieve a film thickness of 20-30μm.