A water-based bio-based salt spray resistant coating and its preparation method and application

Abstract

The present invention provides a water-based bio-based salt-spray resistant coating, and its preparation method and application. The water-based bio-based salt-spray resistant coating of the present invention comprises component A, component B and component C. The raw materials for preparing component A include water-based polyurethane resin, water-based acrylic resin, wetting agent, defoaming agent, anti-rust pigment, solvent, pH regulator, thickener and epoxy phosphate. The raw materials for preparing the water-based polyurethane resin include lignin. The component B includes isocyanate polymer, and the component C includes a silane coupling agent. The coating can be widely used in the fields of 3C consumer electronics and car interior coatings, and can play an anti-rust and protective role on special metal substrates. The present invention also provides a preparation method and application of the water-based bio-based salt-spray resistant coating.

Description

Technical Field

[0001] The present invention belongs to the technical field of coatings, and in particular relates to a water-based bio-based salt spray resistant coating and a preparation method and application thereof. Background Art

[0002] Polyurethane coatings are high-performance coatings widely used in industry and construction. Their excellent performance stems from their chemical composition, which primarily includes polyols and isocyanates. These components react to form polyurethane materials that exhibit excellent wear resistance, corrosion resistance, UV resistance, and excellent adhesion. As a result, polyurethane coatings have gained widespread recognition and application in many applications. In the background technology of polyurethane coatings, polyols are one of their key components. Traditionally, polyols include polyether polyols and polyester polyols, which provide the necessary elasticity and toughness for the coating. The polyurethane formed by the reaction of isocyanates and polyols has a cross-linked structure, which makes the coating excellent in hardness and durability. In addition to the main ingredients, the performance of the coating is also affected by additives such as curing agents, catalysts, pigments, and fillers. These additives can adjust the properties of the coating to suit different application requirements.

[0003] In recent years, with the increasing popularity of consumer electronics and technological advancements, the application of polyurethane coatings in this field has also increased. Coatings for consumer electronics demand not only excellent performance but also cost-effectiveness and environmental friendliness. Against this backdrop, coatings technology faces the challenge of transitioning from multi-coat to single-coat systems. Traditional multi-coat systems offer excellent adhesion, salt spray resistance, artificial sweat resistance, aging resistance, and chemical resistance. However, single-coat systems must meet the same or even higher standards as multi-coat systems in these areas to meet the demands of modern consumer electronics. Achieving this goal not only reduces production costs but also reduces material usage and improves environmental performance. Therefore, optimizing formulations and application processes to ensure that single-coat systems possess all the properties required of multi-coat systems has become a key area of ​​technological development.

[0004] The production process of polyurethane coatings involves complex chemical reactions and meticulous process control. The selection of polyols and isocyanates, the control of reaction conditions, and the use of additives all directly impact the coating's final performance. In the consumer electronics sector, the development of single-coat coatings must not only meet traditional performance requirements but also consider the coating's performance in real-world applications, such as scratch resistance, abrasion resistance, and environmental resistance. Therefore, the technical challenges in developing high-performance single-coat coatings include improving the coating's overall performance while maintaining cost-effectiveness, production feasibility, and environmental friendliness. Despite the significant performance advantages of polyurethane coatings, their production process still presents certain technical challenges. A particularly prominent issue is the high concentration of polyol components in traditional polyurethane coatings, most of which are derived from petrochemical raw materials. The production of petrochemical raw materials not only consumes significant amounts of petroleum resources but also has a significant impact on the environment. For example, the production of polyester polyols requires petroleum-based raw materials, which not only exacerbates resource constraints but also releases large amounts of pollutants such as carbon dioxide. Therefore, to reduce dependence on petrochemical raw materials, explore more environmentally friendly raw material alternatives, and achieve excellent chemical and salt spray resistance, the development of new coatings remains a challenge. Summary of the Invention

[0005] The present invention aims to address at least one of the aforementioned technical problems in the prior art. To this end, the present invention provides a water-based, bio-based, salt-spray-resistant coating that can be widely used in the fields of consumer electronics and automotive interior coatings, providing rust prevention and protection for special metal substrates.

[0006] The present invention also provides a method for preparing a water-based bio-based salt spray resistant coating.

[0007] The present invention also provides a water-based bio-based salt spray resistant coating.

[0008] The present invention also provides the use of the water-based bio-based salt spray resistant coating in consumer electronics or automobile interiors.

[0009] The first aspect of the present invention provides a water-based bio-based salt spray resistant coating, comprising component A, component B and component C, wherein the raw materials for preparing component A include water-based polyurethane resin, water-based acrylic resin, wetting agent, defoaming agent, anti-rust pigment, solvent, pH regulator, thickener and epoxy phosphate, the raw materials for preparing the water-based polyurethane resin include lignin, the component B includes isocyanate polymer, and the component C includes a silane coupling agent.

[0010] One of the technical solutions of the present invention regarding the water-based bio-based salt spray resistant coating has at least the following beneficial effects:

[0011] The present invention provides a water-based bio-based salt spray resistant coating, which can be widely used in the fields of 3C consumer electronics and car interior coatings, and can prevent rust and protect special metal substrates.

[0012] The waterborne bio-based salt spray-resistant coating of the present invention comprises components A, B, and C. Component A is prepared from raw materials including a waterborne polyurethane resin, a waterborne acrylic resin, a wetting agent, a defoamer, an anti-rust pigment, a solvent, a pH adjuster, a thickener, and an epoxy phosphate. The waterborne polyurethane resin is prepared from raw materials including lignin. Lignin is a common bio-based aromatic polymer found in nature and a key component of vascular plants. It has the advantages of abundant reserves, renewable properties, and reasonable price. Lignin contains a large number of active groups, such as aromatic structures, phenolic hydroxyl groups, alcoholic hydroxyl groups, and methoxyl groups, which can be introduced into polyurethane segments by reacting with isocyanates. Due to the unique structure of lignin, the mechanical properties and thermal stability of polyurethane materials can be effectively improved. Lignin can be added to polymer materials in two main ways: physical addition and chemical addition. Physical addition is mainly in the form of fillers, emulsifiers, or prepolymers, while chemical addition utilizes functional groups, such as phenolic and alcoholic hydroxyl groups, contained in lignin to react with isocyanates to produce a bio-based polyurethane material. Bio-based polyurethane materials synthesized using chemical addition methods have significant advantages in mechanical properties and chemical resistance compared to those synthesized using general physical addition methods. However, due to the relatively low number of active sites in natural lignin materials, natural lignin materials usually need to be modified before being synthesized into polyurethane chain segments. Common modification methods include nitration, etherification, esterification, hydroxyalkylation, amination, epoxidation, and demethylation to increase the number of reactive active sites and improve the reaction efficiency of lignin and isocyanate materials.

[0013] The present invention utilizes active groups such as phenolic hydroxyl and alcoholic hydroxyl groups in lignin to introduce lignin into polyurethane chain segments. Lignin is used to partially replace the polyol component in traditional polyurethane synthesis, reducing human consumption and dependence on petrochemical materials. Furthermore, because lignin is a renewable resource with vast reserves in nature, is inexpensive, and readily available, it offers the potential for large-scale future promotion. Because lignin contains aromatic structures, it can enhance the mechanical properties, chemical resistance, and thermal stability of the coating, offering significant performance advantages in the fields of consumer electronics coatings and automotive interior coatings.

[0014] According to some embodiments of the present invention, the mass ratio of component A, component B and component C is 100:10-20:1-3.

[0015] According to some embodiments of the present invention, the isocyanate polymer is at least one of Covestro XP2487 / 1 and Covestro XP2655.

[0016] According to some embodiments of the present invention, the silane coupling agent is at least one of Evonik GLYMO, Momentive MP200, KH-550, and KH-560.

[0017] According to some embodiments of the present invention, the raw materials for preparing component A include, in parts by mass:

[0018] Waterborne polyurethane resin: 40 to 50 parts,

[0019] Water-based acrylic resin: 25 to 38 parts,

[0020] Wetting agent: 0.6 to 1.0 parts,

[0021] Defoaming agent: 0.4 to 0.6 parts,

[0022] Anti-rust pigment: 5 to 8 parts,

[0023] Solvent: 3 to 6 parts,

[0024] pH regulator: 0.05 to 0.1 parts,

[0025] Thickener: 0.2 to 0.35 parts,

[0026] Epoxy phosphate: 3 to 4 parts.

[0027] According to some embodiments of the present invention, the water-based acrylic resin includes at least one of Wanhua 2702 resin, Covestro 2770 resin, and Allnex 6514 resin.

[0028] According to some embodiments of the present invention, the wetting agent includes at least one of Evonik Twin4100, Evonik WET270, and Evonik WET280.

[0029] According to some embodiments of the present invention, the defoaming agent includes at least one of BYK-024, Evonik Tego825 and Evonik Tego845 defoaming agents.

[0030] According to some embodiments of the present invention, the anti-rust pigment includes at least one of modified calcium strontium phosphosilicate and silicon powder.

[0031] Modified calcium strontium phosphosilicate is a highly ionic, anti-rust pigment. The high activity of strontium allows phosphate and silicate ions to quickly form a dense protective layer on the paint film, isolating it from air and moisture. Compared to commonly used anti-rust pigments, modified calcium strontium phosphosilicate and silica powder do not contain harmful heavy metals, making it very user- and environmentally friendly.

[0032] According to some embodiments of the present invention, the solvent includes at least one of diethylene glycol butyl ether and dipropylene glycol butyl ether.

[0033] According to some embodiments of the invention, the pH adjuster comprises at least one of DMEA and AMP-95.

[0034] According to some embodiments of the present invention, the thickener includes at least one of Hemmings 299, Hemmings FX1010 and Evonik Tego3060.

[0035] According to some embodiments of the present invention, the epoxy phosphate includes at least one of Lubrizol 2063 and 2062.

[0036] Epoxy phosphate itself contains a large number of groups that can react with metal substrates, which can enhance the coating's adhesion, water boiling adhesion, salt spray resistance, and artificial sweat resistance on substrates such as aluminum and stainless steel. Combining anti-rust pigments and epoxy phosphate can significantly improve the coating's resistance to salt spray and acid sweat, sufficient to meet the coating's application in the 3C consumer electronics and automotive interior fields.

[0037] According to some embodiments of the present invention, the preparation method of component A comprises the following steps:

[0038] S1: mixing the waterborne polyurethane and waterborne acrylic resin, maintaining a rotation speed of 500 rpm to 800 rpm, and stirring for 5 min to 10 min;

[0039] S2: Add the wetting agent, defoaming agent, and anti-rust pigment in sequence, increase the speed to 1000 rpm to 120 rpm, and stir for 20 min to 30 min;

[0040] S3: adding the solvent, pH regulator, thickener, and epoxy phosphate in sequence, reducing the rotation speed to 500 rpm to 800 rpm, and stirring for 10 min to 15 min.

[0041] According to some embodiments of the present invention, the raw materials for preparing the waterborne polyurethane resin include, in parts by mass:

[0042] Lignin polyol: 5 to 10 parts,

[0043] Polyethylene glycol: 90 to 95 parts,

[0044] Acetone: 200 to 250 parts,

[0045] Isocyanate: 70 to 80 parts,

[0046] First chain extender: 15 to 18 parts,

[0047] Second chain extender: 15 to 18 parts,

[0048] Triethylamine: 1.0-2.0 parts,

[0049] Water: 260.0 parts to 280.0 parts.

[0050] According to some embodiments of the present invention, the lignin is lignin polyol.

[0051] According to some embodiments of the present invention, the polyethylene glycol is at least one of polyethylene glycol 100 (PEG-100), polyethylene glycol 200 (PEG-200), polyethylene glycol 400 (PEG-400), and polyethylene glycol 1000 (PEG-1000).

[0052] According to some embodiments of the present invention, the isocyanate is at least one of hexamethylene diisocyanate (HDI) and isophorone diisocyanate (IPDI).

[0053] According to some embodiments of the present invention, the first chain extender is 1,4-butanediol (BDO).

[0054] According to some embodiments of the present invention, the second chain extender is dimethylol propionic acid (DMPA) or dimethylol butyric acid (DMBA).

[0055] According to some embodiments of the present invention, the method for preparing the waterborne polyurethane resin comprises the following steps:

[0056] (1) vacuum drying and dehydrating the lignin polyol and polyethylene glycol;

[0057] (2) Add the dried and dehydrated lignin polyol, polyethylene glycol and 120 to 150 parts of acetone into a four-necked flask and rotate to control the temperature at 75°C to 85°C;

[0058] (3) Add 70 to 80 parts of isocyanate and 50 to 60 parts of acetone into a four-necked flask and stir at 75°C to 85°C for 2 hours;

[0059] (4) adding 15 to 18 parts of the first chain extender, 15 to 18 parts of the second chain extender and 30 to 40 parts of acetone, and stirring at 75°C to 85°C for 2 hours;

[0060] (5) After cooling to 50° C. to 60° C., stirring is continued, and the triethylamine and water are added to achieve phase inversion. The mixture is kept at 50° C. to 55° C. for 30 min to 45 min to obtain the waterborne polyurethane resin.

[0061] The second aspect of the present invention provides a method for preparing the waterborne bio-based salt spray resistant coating of the first aspect of the present invention, comprising the steps of mixing component A, component B and component C.

[0062] The present invention provides a technical solution for the preparation method of a water-based bio-based salt spray resistant coating, which has at least the following beneficial effects:

[0063] The preparation method of the present invention does not require expensive equipment and complex process control, has non-critical reaction conditions, readily available raw materials, low production costs, and is easy to industrialize. Specifically:

[0064] In terms of environmental friendliness, the use of a water-based system rather than a solvent-based system reduces the use of organic solvents, thereby reducing the emission of volatile organic compounds (VOCs) and reducing environmental pollution. The use of lignin as a bio-based material reduces dependence on traditional petrochemical products, helping to reduce resource consumption and environmental burden.

[0065] In terms of cost-effectiveness, lignin, as a natural and inexpensive bio-based material, can effectively reduce raw material costs and improve economic efficiency. Due to its simple preparation process, no expensive equipment is required, and the reaction conditions are not harsh, it helps reduce production costs and improve the feasibility of industrial production.

[0066] In terms of performance stability, the introduction of lignin into the polyurethane chain improves the coating's mechanical properties, chemical resistance, and thermal stability, thereby enhancing the coating's overall performance and service life. The epoxy phosphate, anti-rust pigments, and other additives in the formula further enhance the coating's salt spray resistance and corrosion resistance, ensuring the coating maintains excellent protection in harsh environments.

[0067] In terms of ease of application and processing, the coating's water-based formulation makes it safer, easier to handle, and easier to clean during application, reducing wear and tear on application equipment and cleaning and maintenance costs. Because the preparation process does not require complex techniques and equipment, it can adapt to production needs of varying scales, from small-scale experiments to large-scale industrial production.

[0068] In terms of wide applicability, the wide range of application areas of this coating (such as 3C consumer electronics, automotive interiors, etc.) gives it a good market prospect and meets the demand for salt spray resistant coatings in different fields.

[0069] The third aspect of the present invention provides a water-based bio-based salt spray resistant coating, which is formed by curing the water-based bio-based salt spray resistant coating according to the first aspect of the present invention.

[0070] The technical solution of the present invention regarding water-based bio-based salt spray resistant coating has at least the following beneficial effects:

[0071] Excellent salt spray resistance effectively protects electronic devices and automotive interiors from salt spray corrosion, extending their service life. Lignin enhances the mechanical strength of the coating, provides better scratch and wear resistance, and maintains long-term appearance and functionality. The use of a water-based formula and bio-based lignin reduces the emission of harmful volatile organic compounds (VOCs), meets environmental standards, and reduces the burden on the environment. Providing a smooth and uniform coating enhances the visual appeal and tactile quality of the product, making electronic devices and interiors more high-end. The coating has excellent chemical resistance, making it easy to clean and maintain, maintaining its appearance and functionality for a long time. As a bio-based material, lignin reduces costs while providing high-performance protection, enhancing the product's cost-effectiveness. It is suitable for a variety of consumer electronics and automotive interiors, and can meet the needs of different fields for coating protection.

[0072] The fourth aspect of the present invention provides the use of the water-based bio-based salt spray resistant coating of the third aspect of the present invention in consumer electronics or automotive interiors.

[0073] The present invention relates to a technical solution for the application of a water-based bio-based salt spray resistant coating in consumer electronics or automotive interiors, which has at least the following beneficial effects:

[0074] It provides excellent salt spray resistance, protecting electronic devices and automotive interiors from corrosion and rust, and extending their service life. The addition of lignin enhances the coating's mechanical strength, improves scratch and abrasion resistance, and ensures long-term durability. The water-based formula reduces the use of harmful solvents and reduces VOC emissions, helping to comply with environmental regulations and enhance the product's green certification. Furthermore, it provides a smooth and uniform coating, improving the appearance quality and surface gloss, and enhancing the visual appeal of consumer electronics and automotive interiors. In addition, the coating has excellent chemical resistance, is easy to clean and maintain, and maintains its appearance and functionality for a long time. In terms of cost, the use of lignin reduces dependence on expensive petrochemical materials, reduces production costs, and provides consumers with a more cost-effective product.

[0075] According to some embodiments of the present invention, consumer electronics refers to electronic products widely used in personal and domestic environments, primarily for entertainment, communication, computing, and various applications in daily life. These products typically have user-friendly interfaces and functions to meet individual needs. Common consumer electronics products include smartphones, tablets, laptops, televisions, game consoles, headphones and sound systems, digital cameras and camcorders, smart home devices, e-book readers, wearable devices, etc. DETAILED DESCRIPTION

[0076] The following are specific embodiments of the present invention, and the technical solutions of the present invention are further described in conjunction with the embodiments, but the present invention is not limited to these embodiments.

[0077] In a first aspect, in some embodiments of the present invention, a water-based bio-based salt spray resistant coating is provided, comprising component A, component B and component C, wherein the raw materials for preparing component A include water-based polyurethane resin, water-based acrylic resin, wetting agent, defoaming agent, anti-rust pigment, solvent, pH regulator, thickener and epoxy phosphate, the raw materials for preparing the water-based polyurethane resin include lignin, component B includes isocyanate polymer, and component C includes a silane coupling agent.

[0078] It can be understood that the present invention provides a water-based bio-based salt spray resistant coating that can be widely used in the fields of 3C consumer electronics and car interior coatings, and can prevent rust and protect special metal substrates.

[0079] The water-based bio-based salt spray-resistant coating of the present invention comprises components A, B, and C. Component A is prepared from raw materials including a water-based polyurethane resin, a water-based acrylic resin, a wetting agent, a defoamer, an anti-rust pigment, a solvent, a pH adjuster, a thickener, and an epoxy phosphate. The water-based polyurethane resin is prepared from raw materials including lignin. Lignin is a common bio-based aromatic polymer found in nature and a key component of vascular plants. It has the advantages of abundant reserves, renewable nature, and reasonable price. Lignin contains a large number of active groups, such as aromatic structures, phenolic hydroxyl groups, alcoholic hydroxyl groups, and methoxyl groups, which can be introduced into polyurethane segments by reacting with isocyanates. Due to the unique structure of lignin, the mechanical properties and thermal stability of polyurethane materials can be effectively improved. Lignin can be added to polymer materials in two main ways: physical addition and chemical addition. Physical addition is mainly in the form of fillers, emulsifiers, or prepolymers, while chemical addition utilizes functional groups, such as phenolic and alcoholic hydroxyl groups, contained in lignin to react with isocyanates to produce a bio-based polyurethane material. Bio-based polyurethane materials synthesized using chemical addition methods have significant advantages in mechanical properties and chemical resistance compared to those synthesized using general physical addition methods. However, due to the relatively low number of active sites in natural lignin materials, natural lignin materials usually need to be modified before being synthesized into polyurethane chain segments. Common modification methods include nitration, etherification, esterification, hydroxyalkylation, amination, epoxidation, and demethylation to increase the number of reactive active sites and improve the reaction efficiency of lignin and isocyanate materials.

[0080] It should be noted that the present invention introduces lignin materials into polyurethane chain segments by utilizing active groups such as phenolic hydroxyl groups and alcoholic hydroxyl groups in lignin materials. The use of lignin polyols partially replaces the polyol components in the synthesis of traditional polyurethane materials, reducing human consumption and dependence on petrochemical materials. At the same time, because lignin materials are renewable resources with huge reserves in nature, are cheap and easy to obtain, it is possible to promote the material on a large scale in the future. Because lignin materials contain aromatic structures, they can improve the mechanical properties, chemical resistance and thermal stability of the coating, and have obvious performance advantages in the fields of consumer electronics coatings and automotive interior coatings.

[0081] In combination with the first aspect, in some embodiments of the present invention, the mass ratio of component A, component B and component C is 100:10-20:1-3.

[0082] In combination with the first aspect, in some embodiments of the present invention, the isocyanate polymer is at least one of Covestro XP2487 / 1 and Covestro XP2655.

[0083] In combination with the first aspect, in some embodiments of the present invention, the silane coupling agent is at least one of Evonik GLYMO, Momentive MP200, KH-550, and KH-560.

[0084] In combination with the first aspect, in some embodiments of the present invention, the raw materials for preparing component A include, in parts by mass:

[0085] Waterborne polyurethane resin: 40 to 50 parts,

[0086] Water-based acrylic resin: 25 to 38 parts,

[0087] Wetting agent: 0.6 to 1.0 parts,

[0088] Defoaming agent: 0.4 to 0.6 parts,

[0089] Anti-rust pigment: 5 to 8 parts,

[0090] Solvent: 3 to 6 parts,

[0091] pH regulator: 0.05 to 0.1 parts,

[0092] Thickener: 0.2 to 0.35 parts,

[0093] Epoxy phosphate: 3 to 4 parts.

[0094] In combination with the first aspect, in some embodiments of the present invention, the water-based acrylic resin includes at least one of Wanhua 2702 resin, Covestro 2770 resin, and Allnex 6514 resin.

[0095] In combination with the first aspect, in some embodiments of the present invention, the wetting agent includes at least one of Evonik Twin4100, Evonik WET270, and Evonik WET280.

[0096] In combination with the first aspect, in some embodiments of the present invention, the defoaming agent includes at least one of BYK-024, Evonik Tego825, and Evonik Tego845 defoaming agents.

[0097] In combination with the first aspect, in some embodiments of the present invention, the anti-rust pigment includes at least one of modified calcium strontium phosphosilicate and silicon powder.

[0098] Modified calcium strontium phosphosilicate is a highly ionic, anti-rust pigment. The high activity of strontium allows phosphate and silicate ions to quickly form a dense protective layer on the paint film, isolating it from air and moisture. Compared to commonly used anti-rust pigments, modified calcium strontium phosphosilicate and silica powder do not contain harmful heavy metals, making it very user- and environmentally friendly.

[0099] In combination with the first aspect, in some embodiments of the present invention, the solvent includes at least one of diethylene glycol butyl ether and dipropylene glycol butyl ether.

[0100] In combination with the first aspect, in some embodiments of the present invention, the pH adjuster includes at least one of DMEA and AMP-95.

[0101] In combination with the first aspect, in some embodiments of the present invention, the thickener includes at least one of Hemmings 299, Hemmings FX1010, and Evonik Tego3060.

[0102] In conjunction with the first aspect, in some embodiments of the present invention, the epoxy phosphate includes at least one of Lubrizol 2063 and 2062.

[0103] Epoxy phosphate itself contains a large number of groups that can react with metal substrates, which can enhance the coating's adhesion, water boiling adhesion, salt spray resistance, and artificial sweat resistance on substrates such as aluminum and stainless steel. Combining anti-rust pigments and epoxy phosphate can significantly improve the coating's resistance to salt spray and acid sweat, sufficient to meet the coating's application in the 3C consumer electronics and automotive interior fields.

[0104] In combination with the first aspect, in some embodiments of the present invention, the preparation method of component A comprises the following steps:

[0105] S1: Mix waterborne polyurethane and waterborne acrylic resin, maintain a rotation speed of 500 rpm to 800 rpm, and stir for 5 min to 10 min;

[0106] S2: Add wetting agent, defoaming agent, and anti-rust pigment in sequence, increase the speed to 1000 rpm to 120 rpm, and stir for 20 min to 30 min;

[0107] S3: Add solvent, pH adjuster, thickener, and epoxy phosphate in sequence, reduce the speed to 500 rpm to 800 rpm, and stir for 10 min to 15 min.

[0108] In step S1, the waterborne polyurethane and waterborne acrylic resins are mixed to improve the performance of the coating. The mixing ensures uniform mixing and improves the stability and consistency of the product.

[0109] In step S2, the wetting agent improves the wettability of the coating on the substrate, enhancing the coating's adhesion. The defoamer removes air bubbles from the coating, preventing the formation of pores. The anti-rust pigment provides salt spray resistance, protecting the substrate from corrosion. Stirring ensures that all components are fully dispersed and mixed.

[0110] In step S3, the solvent adjusts the coating's viscosity and improves its coating properties. The pH adjuster controls the coating's pH value, ensuring the stability of the formulation. The thickener adjusts the coating's consistency and improves its handling properties. The epoxy phosphate provides additional corrosion protection. Stirring ensures even distribution of all additives, completing the final formulation.

[0111] In combination with the first aspect, in some embodiments of the present invention, the raw materials for preparing the waterborne polyurethane resin include, in parts by mass:

[0112] Lignin polyol: 5 to 10 parts,

[0113] Polyethylene glycol: 90 to 95 parts,

[0114] Acetone: 200 to 250 parts,

[0115] Isocyanate: 70 to 80 parts,

[0116] First chain extender: 15 to 18 parts,

[0117] Second chain extender: 15 to 18 parts,

[0118] Triethylamine: 1.0-2.0 parts,

[0119] Water: 260.0 parts to 280.0 parts.

[0120] In combination with the first aspect, in some embodiments of the present invention, the lignin is lignin polyol.

[0121] In combination with the first aspect, in some embodiments of the present invention, the polyethylene glycol is at least one of polyethylene glycol 100 (PEG-100), polyethylene glycol 200 (PEG-200), polyethylene glycol 400 (PEG-400), and polyethylene glycol 1000 (PEG-1000).

[0122] In combination with the first aspect, in some embodiments of the present invention, the isocyanate is at least one of hexamethylene diisocyanate (HDI) and isophorone diisocyanate (IPDI).

[0123] In combination with the first aspect, in some embodiments of the present invention, the first chain extender is 1,4-butanediol (BDO).

[0124] In combination with the first aspect, in some embodiments of the present invention, the second chain extender is dimethylol propionic acid (DMPA) or dimethylol butyric acid (DMBA).

[0125] In combination with the first aspect, in some embodiments of the present invention, the preparation method of the waterborne polyurethane resin comprises the following steps:

[0126] (1) vacuum drying and dehydrating lignin polyol and polyethylene glycol;

[0127] (2) Add the dried and dehydrated lignin polyol, polyethylene glycol and 120 to 150 parts of acetone into a four-necked flask and rotate to control the temperature at 75°C to 85°C;

[0128] (3) Add 70 to 80 parts of isocyanate and 50 to 60 parts of acetone into a four-necked flask and stir at 75°C to 85°C for 2 hours;

[0129] (4) adding 15 to 18 parts of the first chain extender, 15 to 18 parts of the second chain extender, and 30 to 40 parts of acetone, and stirring at 75°C to 85°C for 2 hours;

[0130] (5) After cooling to 50°C to 60°C while stirring, triethylamine and water are added to achieve phase inversion, and the mixture is kept at 50°C to 55°C for 30 min to 45 min to obtain a waterborne polyurethane resin.

[0131] In step (1), the dehydration of the lignin polyol and polyethylene glycol is to remove moisture from the raw materials. The presence of moisture may affect subsequent reaction results, such as the efficiency of the polymerization reaction and the quality of the product. The dehydration process is accelerated by vacuum and high temperature environment to ensure that the materials are completely dry before entering the next step to avoid moisture interference with the reaction.

[0132] In step (2), the lignin polyol and polyethylene glycol are mixed to form a uniform reaction mixture so that the subsequent chemical reaction can proceed evenly. Acetone, as a solvent, helps dissolve the lignin and polyethylene glycol, providing a uniform reaction environment. Heating to increase the temperature promotes the volatilization of the solvent, ensuring that the reaction proceeds within a suitable temperature range.

[0133] In step (3), isocyanate reacts with lignin and polyethylene glycol to form polyurethane. Isocyanate is a key component in polyurethane synthesis. Acetone continues to serve as a solvent to maintain the fluidity and uniformity of the reaction mixture. Stirring and heating can maintain the uniformity of the reaction, promote the reaction, and control the reaction temperature to avoid side reactions.

[0134] In step (4), the first chain extender increases the molecular weight of the polyurethane, improving its physical properties (e.g., wear resistance and mechanical strength). The second chain extender helps improve the stability and functionality of the waterborne polyurethane. Acetone continues to serve as a solvent, promoting a uniform reaction. Heat preservation and stirring ensure uniform chain extension.

[0135] In step (5), triethylamine can promote the aqueous phase transformation of the polyurethane resin. Water causes the synthesized polyurethane to complete the phase transformation, so that the final product is converted into an aqueous system. The purpose of cooling and heat preservation is to control the temperature so that the phase transformation process proceeds smoothly.

[0136] In a second aspect, some embodiments of the present invention provide a method for preparing the waterborne bio-based salt spray resistant coating of the first aspect of the present invention, comprising the steps of mixing component A, component B and component C.

[0137] It can be understood that the preparation method of the present invention does not require expensive equipment and complex process control, the reaction conditions are not harsh, the raw materials are readily available, the production cost is low, and it is easy to industrialize. Specifically:

[0138] In terms of environmental friendliness, the use of a water-based system rather than a solvent-based system reduces the use of organic solvents, thereby reducing the emission of volatile organic compounds (VOCs) and reducing environmental pollution. The use of lignin as a bio-based material reduces dependence on traditional petrochemical products, helping to reduce resource consumption and environmental burden.

[0139] In terms of cost-effectiveness, lignin, as a natural and inexpensive bio-based material, can effectively reduce raw material costs and improve economic efficiency. Due to its simple preparation process, no expensive equipment is required, and the reaction conditions are not harsh, it helps reduce production costs and improve the feasibility of industrial production.

[0140] In terms of performance stability, the introduction of lignin into the polyurethane chain improves the coating's mechanical properties, chemical resistance, and thermal stability, thereby enhancing the coating's overall performance and service life. The epoxy phosphate, anti-rust pigments, and other additives in the formula further enhance the coating's salt spray resistance and corrosion resistance, ensuring the coating maintains excellent protection in harsh environments.

[0141] In terms of ease of application and processing, the coating's water-based formulation makes it safer, easier to handle, and easier to clean during application, reducing wear and tear on application equipment and cleaning and maintenance costs. Because the preparation process does not require complex techniques and equipment, it can adapt to production needs of varying scales, from small-scale experiments to large-scale industrial production.

[0142] In terms of wide applicability, the wide range of application areas of this coating (such as 3C consumer electronics, automotive interiors, etc.) gives it a good market prospect and meets the demand for salt spray resistant coatings in different fields.

[0143] Components A, B, and C are mixed. Component B includes an isocyanate polymer, which enhances the chemical resistance and mechanical properties of the coating. Component C includes a silane coupling agent, which improves the adhesion between the coating and the substrate and enhances the overall performance of the coating.

[0144] In a third aspect, some embodiments of the present invention provide a waterborne bio-based salt spray resistant coating, which is formed by curing the waterborne bio-based salt spray resistant coating according to the first aspect of the present invention.

[0145] As you can understand, the excellent salt spray resistance effectively protects electronic devices and automotive interiors from salt spray corrosion, extending their service life. Lignin enhances the mechanical strength of the coating, provides better scratch and wear resistance, and maintains long-term appearance and functionality. The use of water-based formulas and bio-based lignin reduces the emission of harmful volatile organic compounds (VOCs), meets environmental standards, and reduces the burden on the environment. Providing a smooth and uniform coating enhances the visual appeal and tactile quality of the product, making electronic devices and interiors more high-end. The coating has excellent chemical resistance, making it easy to clean and maintain, maintaining its appearance and functionality for a long time. As a bio-based material, lignin reduces costs while providing high-performance protection, enhancing the product's cost-effectiveness. It is suitable for a variety of consumer electronics products and automotive interiors, and can meet the needs of different fields for coating protection.

[0146] In a fourth aspect, some embodiments of the present invention provide applications of the water-based bio-based salt spray resistant coating according to the third aspect of the present invention in consumer electronics or automotive interiors.

[0147] It can be understood that the water-based bio-based salt spray resistant coating of the present invention provides excellent salt spray resistance, protects electronic equipment and automotive interiors from corrosion and rust, and extends service life. By adding lignin, the mechanical strength of the coating is enhanced, the scratch resistance and wear resistance are improved, and long-term durability is ensured. The water-based formula reduces the use of harmful solvents and reduces VOC emissions, which helps to comply with environmental regulations and improve the green certification of the product. Furthermore, a smooth and uniform coating is provided, which improves the appearance quality and surface gloss, and enhances the visual appeal of consumer electronic products and automotive interiors. In addition, the coating has excellent chemical resistance, is easy to clean and maintain, and maintains long-term appearance and functionality. In terms of cost, the use of lignin reduces dependence on expensive petrochemical materials, reduces production costs, and provides consumers with more cost-effective products.

[0148] In conjunction with the fourth aspect, in some embodiments of the present invention, consumer electronics refers to electronic products widely used in personal and home environments, primarily for entertainment, communication, computing, and various applications in daily life. These products typically feature user-friendly interfaces and functions to meet individual needs. Common consumer electronics products include smartphones, tablets, laptops, televisions, game consoles, headphones and audio systems, digital cameras and camcorders, smart home devices, e-book readers, wearable devices, etc.

[0149] The following will clearly and completely describe the concept and technical effects of the present invention in conjunction with the embodiments to fully understand the purpose, features and effects of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, other embodiments obtained by those skilled in the art without creative work are all within the scope of protection of the present invention.

[0150] In the description of the present invention, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the exemplary expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0151] Unless otherwise specified, "room temperature" in the present invention means 25°C±5°C.

[0152] Unless otherwise specified, “about” in the present invention means that the allowable error is within ±2%.

[0153] If the specific conditions are not specified in the examples, the experiments were carried out under conventional conditions or those recommended by the manufacturer. All reagents or instruments used, if the manufacturer is not specified, are commercially available conventional products.

[0154] In the examples and comparative examples, lignin polyol was prepared by itself. The specific method is:

[0155] 10 parts by mass of calcium lignin sulfonate, 50 parts by mass of polyethylene glycol PEG-400, and 5 parts by mass of phosphoric acid catalyst were used, and the reaction was carried out at 160-170° C. for 1 hour.

[0156] The lignin polyol was obtained by centrifugation and purification under low temperature conditions, washing with 1,4-dioxane and deionized water, and then drying at 110°C.

[0157] Borresperse CA 45 calcium lignin sulfonate was purchased from Shanghai Kainuowei International Trade Co., Ltd.

[0158] Example 1

[0159] A water-based bio-based salt spray resistant coating and paint was prepared, specifically:

[0160] 5 parts by mass of lignin polyol and 90 parts by mass of polyethylene glycol 100 are placed in a vacuum drying oven at 120° C. for dehydration for 24 hours, and then lignin, polyethylene glycol 100 and 120 parts by mass of acetone are added to a four-necked flask, and the temperature is controlled at 75-85° C. by rotating; then 70 parts by mass of HDI and 50 parts by mass of acetone are slowly added to the four-necked flask, the temperature is maintained at 75-85° C., and the reaction is carried out for 2 hours, and 15 parts by mass of 1,4-butanediol (BDO), 15 parts by mass of dimethylolpropionic acid (DMPA) and 30 parts by mass of acetone are slowly added and reacted at 75-85° C. for 2 hours. Finally, triethylamine and water are slowly added after the temperature is lowered to 55° C. to achieve phase inversion, and the temperature is maintained at 50-55° C. for 30 minutes to obtain a waterborne polyurethane resin.

[0161] 40 parts by mass of waterborne polyurethane resin and 25 parts by mass of Wanhua 2702 resin were mixed, maintained at a speed of 650 rpm, and stirred for 5 minutes; 0.6 parts by mass of Evonik Twin 4100, 0.4 parts by mass of BYK-024, 2 parts by mass of modified calcium strontium phosphosilicate, and 3 parts by mass of silicon powder were added in sequence, the speed was increased to 1000-1200 RPM, and stirred for 20 minutes; 3 parts by mass of DBG, 0.05 parts by mass of DMEA, 0.2 parts by mass of Hemmings 299, and 3 parts by mass of epoxy phosphate were added in sequence, the speed was reduced to 500-800 RPM, and stirred for 10 minutes to obtain component A of the waterborne bio-based salt spray resistant coating.

[0162] Components A, XP2487 / 1 and GLYMO of the waterborne bio-based salt spray resistant coating were taken in 100, 16 and 3 parts by mass respectively, fully stirred and mixed, and then sprayed to prepare a waterborne bio-based salt spray resistant coating.

[0163] Example 2

[0164] A water-based bio-based salt spray resistant coating and paint was prepared, specifically:

[0165] 7 parts by mass of lignin polyol, 75 parts by mass of polyethylene glycol 100 and 15 parts by mass of polyethylene glycol 200 are placed in a vacuum drying oven at 120° C. for dehydration for 24 hours. Then, lignin, polyethylene glycol 100, polyethylene glycol 200 and 130 parts by mass of acetone are added to a four-necked flask, and the temperature is controlled at 75-85° C. by rotating. Then, 73 parts by mass of HDI and 55 parts by mass of acetone are slowly added to the four-necked flask, the temperature is maintained at 75-85° C., and the reaction is carried out for 2 hours. Then, 16 parts by mass of BDO, 16 parts by mass of DMPA and 34 parts by mass of acetone are slowly added, and the reaction is carried out at 75-85° C. for 2 hours. Finally, triethylamine and water are slowly added after the temperature is lowered to 55° C. to achieve phase inversion. The temperature is maintained at 50-55° C. for 30 minutes to obtain a waterborne polyurethane resin.

[0166] 45 parts by mass of waterborne polyurethane and 28 parts by mass of Covestro 2770 resin were mixed, maintained at a speed of 650 rpm, and stirred for 7 minutes; 0.8 parts by mass of Evonik Twin4100, 0.5 parts by mass of BYK-024, 2.5 parts by mass of modified calcium strontium phosphosilicate, and 3 parts by mass of silicon powder were added in sequence, the speed was increased to 1000-1200 RPM, and stirred for 25 minutes; 4 parts by mass of DBG, 0.05 parts by mass of DMEA, 0.25 parts by mass of Tego3030, and 3 parts by mass of epoxy phosphate were added in sequence, the speed was reduced to 500-800 RPM, and stirred for 12 minutes to obtain component A of the waterborne bio-based salt spray resistant coating.

[0167] Components A, XP2487 / 1 and MP200 of the waterborne bio-based salt spray resistant coating were taken in 100, 16 and 3 parts by mass respectively, fully stirred and mixed, and then sprayed to prepare a waterborne bio-based salt spray resistant coating.

[0168] Example 3

[0169] A water-based bio-based salt spray resistant coating and paint was prepared, specifically:

[0170] 7 parts by mass of lignin polyol, 80 parts by mass of polyethylene glycol 100 and 10 parts by mass of polyethylene glycol 400 are placed in a vacuum drying oven at 120° C. and dehydrated for 24 hours. Then, lignin, polyethylene glycol 100, polyethylene glycol 400 and 140 parts by mass of acetone are added to a four-necked flask, and the temperature is controlled at 75-85° C. with rotation. Then, 73 parts by mass of IPDI and 55 parts by mass of acetone are slowly added to the four-necked flask, the temperature is maintained at 75-85° C., and the reaction is carried out for 2 hours. Then, 17 parts by mass of BDO, 17 parts by mass of DMBA and 37 parts by mass of acetone are slowly added, and the reaction is carried out at 75-85° C. for 2 hours. Finally, the temperature is lowered to 55° C., triethylamine and water are slowly added to achieve phase inversion, and the temperature is maintained at 50-55° C. for 30 minutes to obtain a waterborne polyurethane resin.

[0171] 48 parts by mass of waterborne polyurethane and 33 parts by mass of Covestro 2770 resin were mixed, maintained at a speed of 650 rpm, and stirred for 9 minutes; 0.8 parts by mass of Evonik WET270, 0.5 parts by mass of Evonik Tego825, 2.5 parts by mass of modified calcium strontium phosphosilicate and 3 parts by mass of silicon powder were added in sequence, the speed was increased to 1000-1200 RPM, and stirred for 27 minutes; 4 parts by mass of DPNB, 0.07 parts by mass of DMEA, 0.25 parts by mass of Hemmings FX1010, and 4 parts by mass of epoxy phosphate were added in sequence, the speed was reduced to 500-800 RPM, and stirred for 14 minutes to obtain component A of the waterborne bio-based salt spray resistant coating.

[0172] Components A, XP2655 and KH-550 of the waterborne bio-based salt spray resistant coating were taken in 100, 16 and 3 parts by mass respectively, fully stirred and mixed, and then sprayed to prepare a waterborne bio-based salt spray resistant coating.

[0173] Comparative Example 1

[0174] A water-based bio-based salt spray resistant coating and paint was prepared, specifically:

[0175] 10 parts by mass of lignin polyol, 80 parts by mass of polyethylene glycol 100, and 15 parts by mass of polyethylene glycol 1000 are placed in a vacuum drying oven at 120° C. for dehydration for 24 hours. Then, lignin, polyethylene glycol 100, polyethylene glycol 400, and 150 parts by mass of acetone are added to a four-necked flask, and the temperature is controlled at 75-85° C. with rotation. Then, 60 parts by mass of HDI, 20 parts by mass of IPDI, and 60 parts by mass of acetone are slowly added to the four-necked flask, the temperature is maintained at 75-85° C., and the reaction is carried out for 2 hours. Then, 18 parts by mass of BDO, 18 parts by mass of DMPA, and 40 parts by mass of acetone are slowly added, and the reaction is carried out at 75-85° C. for 2 hours. Finally, the temperature is cooled to 55° C., and triethylamine and water are slowly added to achieve phase inversion. The mixture is kept at 50-55° C. for 30 minutes to obtain a waterborne polyurethane resin.

[0176] 50 parts by mass of waterborne polyurethane and 38 parts by mass of allnex 6514 resin were mixed, the speed was maintained at 650 rpm, and stirring was carried out for 10 minutes; 1.0 parts by mass of Evonik WET280 and 0.6 parts by mass of Evonik Tego845 were added in sequence, the speed was increased to 1000-1200 RPM, and stirring was carried out for 30 minutes; 5 parts by mass of DPNB, 0.1 parts by mass of DMEA, 0.1 parts by mass of Hemmings 299, and 0.25 parts by mass of Hemmings FX1010 were added in sequence, the speed was reduced to 500-800 RPM, and stirring was carried out for 15 minutes to obtain component A of the waterborne bio-based salt spray resistant coating.

[0177] Components A, XP2655 and KH-560 of the waterborne bio-based salt spray resistant coating were taken in 100, 16 and 3 parts by mass respectively, fully stirred and mixed, and then sprayed to prepare a waterborne bio-based salt spray resistant coating.

[0178] The properties of the coatings of Examples 1 to 3 (with the same coating thickness) were tested. The results are shown in Table 1.

[0179] Table 1

[0180]

[0181]

[0182]

[0183] As can be seen from Table 1, the present invention introduces lignin materials into polyurethane segments by utilizing active groups such as phenolic hydroxyl groups and alcoholic hydroxyl groups in lignin materials. The use of lignin polyols partially replaces the polyol components in the synthesis of traditional polyurethane materials, reducing human consumption and dependence on petrochemical materials. At the same time, because lignin materials are a renewable resource with huge reserves in nature, are inexpensive, and easy to obtain, it can provide possibilities for the large-scale promotion of this material in the future. Because lignin materials contain aromatic structures, they can improve the mechanical properties, chemical resistance, and thermal stability of the coating, and have obvious performance advantages in the fields of consumer electronics coatings and automotive interior coatings.

[0184] In Comparative Example 1, since no anti-rust pigment and phosphate were added, the coating did not form a passivation layer on the metal surface, and its resistance to salt spray and acidic sweat was weak. The material would oxidize in salt spray and acidic environments, causing bulging and blistering of the coating.

[0185] The present invention has been described in detail above with reference to the embodiments. However, the present invention is not limited to the above embodiments. Various changes can be made within the scope of knowledge possessed by ordinary technicians in the relevant technical field without departing from the spirit of the present invention.

Claims

1. A water-based bio-based salt spray resistant coating, characterized in that: It consists of component A, component B and component C. The raw materials for preparing the component A include waterborne polyurethane resin, waterborne acrylic resin, wetting agent, defoaming agent, anti-rust pigment, solvent, pH regulator, thickener and epoxy phosphate, and the raw materials for preparing the waterborne polyurethane resin include lignin polyol. The raw materials for preparing the waterborne polyurethane resin include: Lignin polyol: 5 to 10 parts, Polyethylene glycol: 90 to 95 parts, Acetone: 200 to 250 parts, Isocyanate: 70 to 80 parts, First chain extender: 15 to 18 parts, Second chain extender: 15 to 18 parts, Triethylamine: 1.0-2.0 parts, Water: 260.0 parts to 280.0 parts; The component B is an isocyanate polymer, The component C is a silane coupling agent, The mass ratio of component A, component B and component C is 100:10-20:1-3.

2. The water-based bio-based salt spray resistant coating according to claim 1, characterized in that: In parts by mass, the raw materials for preparing component A include: Waterborne polyurethane resin: 40 to 50 parts, Water-based acrylic resin: 25 to 38 parts, Wetting agent: 0.6 to 1.0 parts, Defoaming agent: 0.4 to 0.6 parts, Anti-rust pigment: 5 to 8 parts, Solvent: 3 to 6 parts, pH regulator: 0.05 to 0.1 parts, Thickener: 0.2 to 0.35 parts, Epoxy phosphate: 3 to 4 parts.

3. The water-based bio-based salt spray resistant coating according to claim 1 or 2, characterized in that: The water-based acrylic resin includes at least one of Wanhua 2702 resin, Covestro 2770 resin and Allnex 6514 resin.

4. The water-based bio-based salt spray resistant coating according to claim 1 or 2, characterized in that: The wetting agent includes at least one of Evonik Twin4100, Evonik WET270 and Evonik WET280.

5. The water-based bio-based salt spray resistant coating according to claim 1 or 2, characterized in that: The defoaming agent includes at least one of BYK-024, Evonik Tego825 and Evonik Tego845 defoaming agents.

6. The water-based bio-based salt spray resistant coating according to claim 1 or 2, characterized in that: The anti-rust pigment includes at least one of modified calcium strontium phosphosilicate and silicon powder.

7. The water-based bio-based salt spray resistant coating according to claim 1 or 2, characterized in that: The solvent includes at least one of diethylene glycol butyl ether and dipropylene glycol butyl ether.

8. The water-based bio-based salt spray resistant coating according to claim 1 or 2, characterized in that: The pH adjuster includes at least one of DMEA and AMP-95.

9. The water-based bio-based salt spray resistant coating according to claim 1 or 2, characterized in that: The thickener includes at least one of Hemmings 299, Hemmings FX1010 and Evonik Tego3060.

10. The water-based bio-based salt spray resistant coating according to claim 1 or 2, characterized in that: The epoxy phosphate ester includes at least one of Lubrizol 2063 and 2062.

11. The water-based bio-based salt spray resistant coating according to claim 1 or 2, characterized in that: The preparation method of component A comprises the following steps: S1: mixing the waterborne polyurethane and waterborne acrylic resin, maintaining a rotation speed of 500 rpm to 800 rpm, and stirring for 5 min to 10 min; S2: Add the wetting agent, defoaming agent, and anti-rust pigment in sequence, increase the speed to 1000 rpm to 120 rpm, and stir for 20 min to 30 min; S3: adding the solvent, pH regulator, thickener, and epoxy phosphate in sequence, reducing the rotation speed to 500 rpm to 800 rpm, and stirring for 10 min to 15 min.

12. The water-based bio-based salt spray resistant coating according to claim 1, characterized in that: The preparation method of the waterborne polyurethane resin comprises the following steps: (1) vacuum drying and dehydrating the lignin polyol and polyethylene glycol; (2) Add the dried and dehydrated lignin polyol, polyethylene glycol and 120 to 150 parts of acetone into a four-necked flask and rotate to control the temperature at 75°C to 85°C; (3) Add 70 to 80 parts of isocyanate and 50 to 60 parts of acetone into a four-necked flask and stir at 75°C to 85°C for 2 hours; (4) adding 15 to 18 parts of the first chain extender, 15 to 18 parts of the second chain extender and 30 to 40 parts of acetone, and stirring at 75°C to 85°C for 2 hours; (5) After cooling to 50° C. to 60° C., stirring is continued, and the triethylamine and water are added to achieve phase inversion. The mixture is kept at 50° C. to 55° C. for 30 min to 45 min to obtain the waterborne polyurethane resin.

13. The method for preparing a waterborne bio-based salt spray resistant coating according to any one of claims 1 to 12, characterized in that: The method comprises the steps of mixing component A, component B and component C.

14. A water-based bio-based salt spray resistant coating, characterized in that: The coating is formed by curing the waterborne bio-based salt spray resistant coating according to any one of claims 1 to 12.

15. Use of the water-based bio-based salt spray resistant coating according to claim 14 in consumer electronics or automotive interiors.

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