100% solids zero voc radiation cured topcoat and method of making and use thereof

Abstract

The present application relates to a kind of 100% solid content zero VOC radiation-cured finish, its components include 5-60% olefin resin, 5-40% diluent monomer, 1-60% coloring pigment, 0.1-10% photoinitiator, 1-19% matting powder, 0.5-9% auxiliary, the total of above-mentioned component mass percentage is 100%.The 100% solid content zero VOC radiation-cured finish does not contain solvent and water, by the combination of olefin resin and diluent monomer and other components, can realize full solid content while having excellent processability, chemical resistance, corrosion resistance, weather resistance and other properties, and has the advantages of low harmful substance content, zero VOC emission, etc., when using ultraviolet pre-solidification and electron beam curing process, can realize surface gloss controllable while low energy consumption.The present application also includes the preparation method and application of the 100% solid content zero VOC radiation-cured finish.

Description

Technical Field

[0001] This invention relates to the fields of household appliance and industrial coatings, specifically to a radiation-cured topcoat with 100% solids content and zero VOCs, its preparation method, and its application. Background Technology

[0002] Pre-coated color steel sheets or color-coated sheets refer to steel sheets made from cold-rolled steel sheets or galvanized steel sheets that have been coated. The coating process typically involves applying a primer and a topcoat using methods such as roller coating. The topcoat is primarily used for decoration and to meet certain special functional requirements, while the primer is mainly used to bond the substrate and the topcoat, and also provides corrosion protection.

[0003] To meet diverse functional and decorative needs, the manufacturing process of pre-coated color steel sheets and color-coated sheets typically includes high-temperature rapid baking. However, with global warming, energy-saving and emission-reducing coating methods are key technologies that color steel sheet manufacturers and the entire supply chain are striving to develop. In recent years, low-carbon emission-reducing coating processes such as low-temperature curing and electromagnetic induction heating have been the focus of research and development in the field. Compared with traditional thermosetting baking methods, these technologies have significant advantages in energy saving, but the coatings used in these processes are still solvent-based, with a solid content generally between 40% and 70%, resulting in high VOC emissions and significant carbon emissions during high-temperature baking.

[0004] With the continuous development of science and technology, radiation-cured coatings with 100% solid content and reduced carbon emissions have been increasingly successfully applied in industries such as packaging, wood coatings, and furniture. However, there is still a lack of zero-VOC topcoats that can be cured using low-energy radiation curing. At the same time, to prevent light pollution, there is a high market demand for matte topcoats with medium to low gloss (60° gloss is generally 20-70, with 40±10 being the most common). How to control gloss and achieve medium gloss when using topcoats with zero-VOC, low-viscosity coating systems is a problem that urgently needs to be solved in existing technologies.

[0005] In view of this, there is an urgent need in the field to develop a radiation-cured topcoat with 100% solids content and zero VOCs in order to solve the problems faced in the existing technology field. Summary of the Invention

[0006] Based on the above facts, the purpose of this invention is to provide a radiation-cured topcoat with 100% solid content and zero VOCs. It contains no solvents or water and, through the combination of components such as olefin resins and diluent monomers, can achieve excellent processability, chemical resistance, corrosion resistance, and weather resistance while being fully solid. It also has the advantages of low content of harmful substances and zero VOC emissions. When using the ultraviolet pre-curing followed by electron beam curing process, it can achieve controllable surface gloss with low energy consumption.

[0007] The first aspect of the present invention provides a radiation-cured topcoat with 100% solids content and zero VOCs, comprising, by weight percentage:

[0008]

[0009] The total mass percentage of all the above components is 100%.

[0010] Olefin resins

[0011] In some embodiments of the present invention, the olefin resin is selected from one or more of epoxy acrylates, polyurethane acrylates, and polyester acrylates with a double bond functional group number greater than or equal to 1 and a number average molecular weight of 500-10000; preferably, the olefin resin is selected from one or more of epoxy acrylates, polyurethane acrylates, and polyester acrylates with a double bond functional group number of 2-4 and a number average molecular weight of 1000-5000.

[0012] Specifically, the epoxy acrylate is selected from one or a combination of epoxy acrylates (model CN104 NS) and epoxy diacrylates (model CNUVE151 NS) provided by Sartoma; the polyurethane acrylate is selected from low-viscosity aromatic monoacrylates (models CN966 NS, CN9893 NS, CN131 NS) and polyurethane acrylates (model CN91518-NS) provided by Sartoma, polyurethane acrylates (models Ebecryl8809, Ebercryl 1258, Ebecryl 4740, EBECRYL 242N) provided by Zhanxin Resin (China) Co., Ltd., polyurethane acrylates (model EtercureDR-J1010) provided by Changxing Special Materials (Suzhou) Co., Ltd., and polyurethane acrylates (models Laromer UA9048, Laromer UA9050, Laromer UA) provided by BASF. One or more of the polyurethane acrylates of 9186, UA8987, and UA19T; the polyester acrylate is selected from one or a combination of polyester acrylates of Etercure DR-E524 provided by Changxing Special Materials (Suzhou) Co., Ltd. and EBECRYL 810 provided by Zhanxin Resin (China) Co., Ltd.

[0013] Diluted monomer

[0014] In this invention, the diluting monomer is selected from one or more reactive monomers with double bonds.

[0015] Specifically, the diluent monomers are selected from one or more of the following: EM70, EM212, EM2387, EM222, and EM223 provided by Changxing Special Materials (Suzhou) Co., Ltd.; EBECRYL113, EBECRYL114, EBECRYL CTFA, and EBECRYLIBOMA provided by Zhanxin Resins (China) Co., Ltd.; SR203, SR285, SR339, and SR420 provided by Sartoma Company; and VISIOMR BNMA provided by Evonik Corporation.

[0016] Coloring pigments

[0017] In this invention, the coloring pigment is selected from one or more of inorganic pigments and organic pigments.

[0018] Specifically, the inorganic pigment is selected from one or more of R-216 titanium dioxide, F-200 carbon black, iron yellow, iron red, and cobalt blue, and the organic pigment is selected from one or more of JHV-2303w pigment violet, DDP red, phthalocyanine blue, and PY139.

[0019] Photoinitiator

[0020] In some embodiments of the present invention, the photoinitiator is selected from one or more commercially available initiators.

[0021] Specifically, the initiator is selected from one or more of the photoinitiators provided by IGM Corporation, namely TPO, TPOL, 127, 184, 1173, 907, and 819, and by Jiuri New Materials Co., Ltd., namely 1118 and 1127.

[0022] Matte powder

[0023] In some embodiments of the present invention, the matting powder is selected from one or more of organic matting powders and inorganic matting powders.

[0024] Specifically, the inorganic matting agent is selected from one or more of the inorganic matting agents provided by Grace Company with the model numbers Syloid RAD 2111, Syloid 2115, and Syloid ED80, and the inorganic matting agents provided by Evonik with the model numbers Acenatt 810, Acenatt 3600, Acenatt 3300, and Acenatt TS100; the organic matting agent is selected from one or more of the organic matting agents provided by Changxing Materials Industry Co., Ltd. with the model numbers P-CT-20 and P-CT10, the organic matting agents provided by Hongsheng Silica Co., Ltd. with the model numbers TSA560, TSA570, TSA590, and TSA512, and the organic matting agents provided by Zhejiang Jingtong Technology Co., Ltd. with the model numbers NMT-3, NMT-5, NMT-7, NMT-10, and NMT20.

[0025] Additives

[0026] In some embodiments of the present invention, the additives are selected from one or more of defoamers, leveling agents, wetting agents, and dispersing agents, and the 100% radiation-cured topcoat with zero VOC solids content contains, by weight percentage:

[0027]

[0028] The total mass percentage of all the above components is 0.5-9%.

[0029] A second aspect of the present invention provides a method for preparing a radiation-cured topcoat with 100% solids content and zero VOC as described in the first aspect of the present invention, comprising the following steps:

[0030] S1: Under stirring, add part of the diluted monomer and part or all of the additives to the container in sequence, disperse with a high-speed disperser for 15-30 minutes, and control the stirring speed at 1500-2000 rpm to obtain a uniformly mixed material A.

[0031] S2: Keep stirring and control the stirring speed at 2800-3500 rpm. Add coloring pigment to material A to obtain a uniformly mixed material B. Adjust the viscosity of material B to between 80 KU and 120 KU using the remaining diluent monomer.

[0032] S3: Stop stirring, transfer material B to a sand mill, grind for 2 hours until the fineness is ≤10μm, and obtain material C;

[0033] S4: Transfer material C to a dilution vessel, and add olefin resin, remaining additives, matting powder, and photoinitiator in sequence to obtain the radiation-cured topcoat with 100% solid content and zero VOC.

[0034] A third aspect of the present invention provides an application of the radiation-cured topcoat with 100% solids content and zero VOC as described in the first aspect of the present invention, characterized in that the radiation-cured topcoat with 100% solids content and zero VOC is applied as a pre-coating onto coils or steel coils.

[0035] In some embodiments of the present invention, the coil or coiled steel may undergo pretreatment before use, and the pretreatment is a chromium-free pretreatment.

[0036] In some embodiments of the present invention, the coiled steel is a building material coiled steel; preferably, the material of the building material coiled steel is selected from one of hot-dip galvanized, electro-galvanized, and cold-rolled steel.

[0037] In some preferred embodiments of the present invention, the curing process for the 100% solids-content, zero-VOC radiation-curable topcoat is ultraviolet pre-curing followed by electron beam curing. More preferably, the ultraviolet pre-curing uses one of a gallium lamp, a mercury lamp, or a LEB lamp as the light source, with an energy range of 20-400 mJ / cm². 2 The electron beam curing conditions are a voltage of 90-160 kEV and a dose of 20-80 kGY.

[0038] Beneficial effects of the present invention

[0039] This invention provides a radiation-cured topcoat with 100% solids content and zero VOCs. It contains no solvents or water. Through the combination of components such as olefin resins and diluent monomers, it can achieve 100% solids content and zero VOCs while possessing excellent processability, chemical resistance, corrosion resistance, and weather resistance. It also has the advantages of low content of harmful substances and zero VOC emissions. When using ultraviolet pre-curing and electron beam curing processes, it can achieve controllable surface gloss with low energy consumption, resulting in a topcoat with medium to low gloss (20-70 gloss at 60°, preferably 40±10). Detailed Implementation

[0040] To more clearly illustrate the present invention, the following description, in conjunction with specific embodiments and comparative examples, further clarifies the invention. Those skilled in the art should understand that the specific descriptions below are illustrative rather than restrictive and should not be construed as limiting the scope of protection of the present invention. Unless otherwise specified, the experimental methods used in the following embodiments and comparative examples are conventional methods, and the raw materials and reagents used are products that can be purchased from conventional commercial channels.

[0041] The above technical solution will be described below with reference to specific embodiments.

[0042] Example 1: Preparation of a radiation-cured topcoat with 100% solids content and zero VOCs 1

[0043] According to the formulation in Table 1, a radiation-cured topcoat with 100% solids content and zero VOCs was prepared. The preparation method was as follows:

[0044] S1: Under stirring, add a portion of the diluent monomer, dispersant, and leveling agent to the container in sequence, disperse with a high-speed disperser for 15-30 minutes, and control the stirring speed at 1500-2000 rpm to obtain a uniformly mixed material A.

[0045] S2: Keep stirring and control the stirring speed at 2800-3500 rpm. Add coloring pigment to material A to obtain a uniformly mixed material B. Adjust the viscosity of material B to between 80 KU and 120 KU using the remaining diluent monomer.

[0046] S3: Stop stirring, transfer material B to a sand mill, grind for 2 hours until the fineness is ≤10μm, and obtain material C;

[0047] S4: Transfer material C to a dilution vessel, and add olefin resin, matting agent and photoinitiator in sequence to obtain the radiation-cured topcoat 1 with 100% solid content and zero VOC.

[0048] Comparative Examples 1-2: Preparation of topcoat 1-2 as a comparative example

[0049] Topcoat 1-2 were prepared according to the formulation in Table 1 as comparative examples. Except for the absence of certain components in some preparation steps, the other preparation steps were the same as in Example 1.

[0050] It should be noted that Comparative Example 1 does not contain matting powder or photoinitiator, and Comparative Example 2 does not contain photoinitiator. Neither of them are within the scope of protection of this invention, and therefore they are comparative examples.

[0051] Table 1 Formulations of Example 1 and Comparative Examples 1-2

[0052]

[0053] The topcoats obtained in Example 1 and Comparative Examples 1-2 were applied using a No. 14 wire rod to galvanized and zinc-aluminum-magnesium substrates that had already been coated with matching primers. The curing process is detailed in Table 2, and the performance test results are shown in Tables 3 and 4. Notably, the polyester topcoat and polyester primer used in Comparative Application Example 1 were both existing commercially available products.

[0054] Table 2 shows the curing processes used in the examples and comparative examples.

[0055]

[0056]

[0057] Table 3 Performance test results (galvanized substrate)

[0058]

[0059] Table 4 Performance Test Results (Zinc-coated Aluminum-Magnesium Substrate)

[0060]

[0061] As shown in Tables 3 and 4, the radiation-cured topcoat with 100% solids content and zero VOC obtained by this invention exhibits excellent processability, chemical resistance, corrosion resistance, and weather resistance. When used with a primer, it performs well on galvanized and zinc-aluminum-magnesium substrates, achieving performance equal to or better than commonly used commercial products while simultaneously achieving energy conservation and emission reduction. Furthermore, the UV pre-curing followed by electron beam curing process described in this invention enables controllable surface gloss with low energy consumption, facilitating the attainment of a medium gloss (40 gloss at 60°), which is unattainable with other pre-curing methods.

[0062] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. For those skilled in the art, other variations or modifications can be made based on the above description. It is impossible to exhaustively list all the implementation methods here. All obvious variations or modifications derived from the technical solutions of the present invention are still within the protection scope of the present invention.

Claims

1. A radiation-cured topcoat with 100% solids content and zero VOCs, comprising, by weight percentage: The total mass percentage of all the above components is 100%.

2. The radiation-cured topcoat with 100% solids content and zero VOC as described in claim 1, characterized in that, The olefin resin is selected from one or more of epoxy acrylates, polyurethane acrylates, and polyester acrylates with a double bond functional group number greater than or equal to 1 and a number average molecular weight of 500-10000; preferably, the olefin resin is selected from one or more of epoxy acrylates, polyurethane acrylates, and polyester acrylates with a double bond functional group number of 2-4 and a number average molecular weight of 1000-5000.

3. The radiation-cured topcoat with 100% solids content and zero VOC as described in claim 1, characterized in that, The diluting monomer is selected from one or more reactive monomers with double bonds.

4. The radiation-cured topcoat with 100% solids content and zero VOC as described in claim 1, characterized in that, The coloring pigment is selected from one or more of inorganic pigments and organic pigments; preferably, the inorganic pigment is selected from one or more of R-216 titanium dioxide, F-200 carbon black, iron yellow, iron red, and cobalt blue, and the organic pigment is selected from one or more of JHV-2303w pigment purple, DDP red, phthalocyanine blue, and PY139.

5. The radiation-cured topcoat with 100% solids content and zero VOC according to claim 1, characterized in that, The photoinitiators include, but are not limited to, one or more of the photoinitiators provided by IGM Corporation with the models TPO, TPOL, 127, 184, 1173, 907, and 819, and provided by Jiuri New Materials Co., Ltd. with the models 1118 and 1127.

6. The radiation-cured topcoat with 100% solids content and zero VOC according to claim 1, characterized in that, The matting agent is selected from one or more types of organic matting agents and inorganic matting agents.

7. The radiation-cured topcoat with 100% solids content and zero VOC according to claim 1, characterized in that, The additives are selected from one or more of defoamers, leveling agents, wetting agents, and dispersing agents, and by mass percentage, the 100% solids-content zero-VOC radiation-cured topcoat contains: The total mass percentage of all the above components is 0.5-9%.

8. A method for preparing a radiation-cured topcoat with 100% solids content and zero VOC as described in any one of claims 1-7, characterized in that, Includes the following steps: S1: Under stirring, add part of the diluted monomer and part or all of the additives to the container in sequence, disperse with a high-speed disperser for 15-30 minutes, and control the stirring speed at 1500-2000 rpm to obtain a uniformly mixed material A. S2: Keep stirring and control the stirring speed at 2800-3500 rpm. Add coloring pigment to material A to obtain a uniformly mixed material B. Adjust the viscosity of material B to between 80 KU and 120 KU using the remaining diluent monomer. S3: Stop stirring, transfer material B to a sand mill, grind for 2 hours until the fineness is ≤10μm, and obtain material C; S4: Transfer material C to a dilution vessel, and add olefin resin, remaining additives, matting powder, and photoinitiator in sequence to obtain the radiation-cured topcoat with 100% solid content and zero VOC.

9. An application of a radiation-cured topcoat with 100% solids content and zero VOC as described in any one of claims 1-7, characterized in that, The 100% solids-content, zero-VOC radiation-cured topcoat is applied to coils or steel coils; preferably, the coils or steel coils undergo pretreatment before use, and the pretreatment is a chromium-free pretreatment; more preferably, the steel coils are building material steel coils, and the material is preferably one of hot-dip galvanized, electro-galvanized, or cold-rolled steel.

10. The application of the radiation-cured topcoat with 100% solids content and zero VOC according to claim 9, characterized in that, The curing process for the 100% solids-content, zero-VOC radiation-curable topcoat is ultraviolet pre-curing followed by electron beam curing; preferably, the ultraviolet pre-curing uses one of the following as the light source: a galvanic lamp, a mercury lamp, or a LEB lamp, with an energy range of 20-400 mJ / cm². 2 The electron beam curing conditions are a voltage of 90-160 kEV and a dose of 20-80 kGY.

Images