Water-based UV insulating paint for aluminum plastic film of soft package battery as well as preparation method and application of water-based UV insulating paint

Abstract

The invention discloses a water-based UV insulating coating for a soft package battery aluminum plastic film and a preparation method and application thereof, and belongs to the technical field of coatings, the water-based UV insulating coating comprises the following components by weight: 50-80% of water-based UV resin, 5-15% of a water-based polyolefin emulsion, 0.5-3% of di (acetylacetone) diisopropyl titanate, 2-6% of a photoinitiator, 0.5-3% of an auxiliary agent, 2-8% of a quick drying agent, 0-6% of a matting agent, 0-15% of a pigment, and 0-10% of water; the water-based UV resin is an aliphatic polyurethane acrylate oligomer dispersion with two functional groups. The water-based UV insulating paint for the aluminum-plastic film of the soft package battery has excellent performance, has excellent electrical insulation performance, corrosion resistance and adhesive force, has excellent adhesion performance, has good adhesive force on the aluminum-plastic film, and greatly improves the yield of the soft package battery.

Description

Technical Field

[0001] The invention relates to the technical field of coatings, and in particular to a water-based UV insulating coating for an aluminum-plastic film of a soft-pack battery, and a preparation method and application thereof. Background Art

[0002] The aluminum-plastic film on the outside of the soft-pack battery is a multi-layer film structure, with the outermost layer being a nylon layer. The aluminum-plastic film for soft-pack batteries is generally stamped and formed, and then protected by applying glue on the nylon layer and bonding it to the PET and PI films, and finally filled with electrolyte. However, this film-pasting method has a relatively slow coating speed, multiple layers overlap at the closed joints, and the battery is prone to blistering during application and use, and the process is complicated.

[0003] Patent CN116102978A discloses an electrolyte pollution-resistant coating for lithium battery soft-pack aluminum-plastic film, and its preparation method and application, which is based on water-based polyester modified silicone resin, quick-drying water-based alkyd resin, and water-based isocyanate curing agent to improve curing ability and reduce baking curing temperature. However, this solution requires high-temperature baking at 100-115°C, which poses a greater potential danger in battery factories, and electrolyte filling can only be carried out after spraying the coating.

[0004] Therefore, it is necessary to provide a water-based UV insulating coating with good electrical properties, electrolyte resistance, and bonding and adhesion properties. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a water-based UV insulating coating for aluminum-plastic film of soft-pack batteries, a preparation method and application thereof, and a water-based UV insulating coating with excellent performance. The water-based UV insulating coating has excellent electrical insulation performance, corrosion resistance and adhesion, and also has excellent bonding and adhesion performance, good adhesion on the aluminum-plastic film, thereby greatly improving the yield rate of soft-pack batteries.

[0006] To achieve the above object, the technical solution adopted by the present invention is:

[0007] A water-based UV insulating coating for an aluminum-plastic film of a soft-pack battery, comprising the following components in percentage by weight: 50-80% of a water-based UV resin, 5-15% of a water-based polyolefin emulsion, 0.5-3% of di(acetylacetonate)titanate diisopropyl, 2-6% of a photoinitiator, 0.5-3% of an auxiliary agent, 2-8% of a quick-drying agent, 0-6% of a matting agent, 0-15% of a pigment, and 0-10% of water;

[0008] The water-based UV resin is a difunctional aliphatic polyurethane acrylate oligomer dispersion.

[0009] The present invention combines the above-mentioned various raw materials in a specific ratio to obtain a water-based UV insulating coating with excellent performance. The water-based UV insulating coating has excellent electrical insulation performance, corrosion resistance and adhesion, and also has excellent bonding and adhesion performance, and has good adhesion on aluminum-plastic film, thereby greatly improving the yield rate of soft-pack batteries.

[0010] Compared with the currently commonly used insulating film application scheme, the water-based UV insulating coating for the soft-pack battery aluminum-plastic film of the present invention is more convenient, more efficient and less costly. At the same time, different decorative protective coatings can be quickly prepared by adding different color pastes, which is convenient for manufacturers to distinguish and select.

[0011] The water-based UV insulating coating for the aluminum-plastic film of the soft-pack battery of the present invention can be dried / UV-cured to form a film at a low temperature in a short time, without the need for high temperatures above 100°C (which can damage the soft-pack battery and cause explosion hazards). Therefore, after the electrolyte is filled into the soft-pack battery, the final spraying construction and curing to form a film can be performed to protect the soft-pack battery, thus saving the process flow.

[0012] The present invention creatively combines water-based UV resin and water-based polyolefin emulsion. The polar groups in the difunctional aliphatic polyurethane acrylate oligomer dispersion and the non-polar carbon chain of the polyolefin emulsion form a uniform dispersed phase through physical entanglement or microscopic phase separation, effectively eliminating phase separation in the system, improving film-forming stability and uniformity, and improving the stability of the coating. The difunctional aliphatic polyurethane acrylate oligomer and the flexible matrix give the film good ductility and impact resistance, avoiding cracking caused by mechanical stress after film formation. The water-based polyolefin emulsion provides high strength and hardness. The two are combined to form a rigid and flexible composite film. In the water-based system, the dispersion particle size of the difunctional aliphatic polyurethane acrylate oligomer dispersion is small, which helps to form a dense and smooth film on the surface of the substrate. The particles in the polyolefin emulsion are large, providing a skeleton support for the film. The urethane dispersion fills the micropores between the polyolefin particles, improving the density of the film. The difunctional aliphatic polyurethane acrylate oligomer dispersion has a high tolerance to acidic and alkaline environments, and the chemical stability of the film is further improved after the acrylate is cross-linked. The composite film formed by the combination of the two has excellent corrosion resistance. At the same time, the compatibility of the water-based polyolefin emulsion with the plastic matrix enables the coating to be better combined with the non-polar plastic substrate. Under the synergistic effect of the two, the performance of the coating is significantly improved, making it a water-based UV insulating coating with excellent performance. The water-based UV insulating coating has excellent electrical insulation performance, corrosion resistance and adhesion, and also has excellent bonding and adhesion performance, good adhesion on aluminum-plastic film, which greatly improves the yield rate of soft-pack batteries.

[0013] As a preferred embodiment of the present invention, the viscosity of the water-based UV resin at 25° C. is 80 to 140 mPa·S, and the pH value of the water-based UV resin is 7.4 to 7.6.

[0014] As a preferred embodiment of the present invention, the viscosity of the aqueous polyolefin emulsion at 25° C. is ≤600 mPa·S; and the particle size of the aqueous polyolefin emulsion is <300 nm.

[0015] As a preferred embodiment of the present invention, the weight ratio of the aqueous UV resin to the aqueous polyolefin emulsion is (5-9):1.

[0016] As a preferred embodiment of the present invention, the photoinitiator includes at least one of 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1-(4-methylthiophenyl)-2-morpholinyl-1-propanone, 2-hydroxy-2-methylpropiophenone, and phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide.

[0017] As a preferred embodiment of the present invention, the auxiliary agent includes at least one of a leveling agent, a defoaming agent, and a wetting agent.

[0018] As a preferred embodiment of the present invention, the quick-drying agent includes at least one of propylene glycol methyl ether, dipropylene glycol methyl ether and ethanol;

[0019] The matting agent includes at least one of fumed silica and precipitated silica;

[0020] The pigment includes at least one of Pigment Red 254, Phthalocyanine Blue BGS, carbon black, titanium dioxide, iron red, and iron black.

[0021] The present invention also provides a method for preparing a water-based UV insulating coating for a soft-pack battery aluminum-plastic film, comprising the following steps:

[0022] The water-based UV resin, the water-based polyolefin emulsion, the photoinitiator, the auxiliary agent, the quick-drying agent, the pigment and the water are uniformly mixed to obtain the water-based UV insulating coating for the aluminum-plastic film of the soft-pack battery.

[0023] The present invention also provides an application of a water-based UV insulating coating for an aluminum-plastic film of a soft-pack battery in the field of corrosion protection and insulation of the soft-pack battery.

[0024] As a preferred embodiment of the present invention, the electrolyte is filled into the soft-pack battery, and the surface of the nylon layer of the soft-pack battery aluminum-plastic film is coated with a water-based UV insulating coating, and the coating is baked at 50 to 60°C until the water evaporates, and then cured into a film under ultraviolet light to form an anti-corrosion insulating coating.

[0025] The beneficial effects of the present invention are: (1) The water-based UV insulating coating of the present invention has excellent electrical insulation performance, corrosion resistance and adhesion, and also has excellent bonding and adhesion performance, and has good adhesion on aluminum-plastic film, which greatly improves the yield rate of soft-pack batteries.

[0026] (2) Compared with the currently commonly used insulating film application scheme, the water-based UV insulating coating for the soft-pack battery aluminum-plastic film of the present invention is more convenient, more efficient and less costly. At the same time, different decorative protective coatings can be quickly prepared by adding different color pastes, which is convenient for manufacturers to distinguish and select.

[0027] (3) The water-based UV insulating coating for the aluminum-plastic film of the soft-pack battery of the present invention can be dried / UV-cured to form a film at low temperature in a short time, without the need for high temperatures above 100°C (which may damage the soft-pack battery and cause explosion hazard). Therefore, after the electrolyte is filled into the soft-pack battery, the final spraying construction and curing to form a film can be carried out to protect the soft-pack battery, thus saving the process flow. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application are described clearly and completely below. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0029] In the present application, the technical features described in an open manner include closed technical solutions composed of the listed features, and also include open technical solutions containing the listed features.

[0030] In this application, when it comes to numerical ranges, unless otherwise specified, the above numerical ranges are deemed to be continuous and include the minimum and maximum values ​​of the range, as well as each value between such minimum and maximum values. Further, when a range refers to an integer, each integer between the minimum and maximum values ​​of the range is included. In addition, when multiple ranges are provided to describe features or characteristics, the ranges can be merged. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges included therein.

[0031] In the present application, there is no particular limitation on the specific dispersion and stirring treatment methods.

[0032] The raw materials used in the embodiments and comparative examples are described as follows:

[0033] Water-based UV resin-1: a difunctional aliphatic polyurethane acrylate oligomer dispersion, with a viscosity of 110 mPa·S at 25° C., a pH value of 7.5, and is sourced from Guangdong Yunhai New Materials, with a brand name of HYF6021.

[0034] Water-based UV resin-2: from Guangzhou Wuxing Material Technology Co., Ltd., brand WU3202.

[0035] Water-based UV resin-3: from Guangzhou Haohui New Materials Co., Ltd., brand CR92001.

[0036] Water-based UV resin-3: from Guangzhou Lankelu New Materials Co., Ltd., brand L-9821.

[0037] Aqueous polyolefin emulsion-1: viscosity at 25°C ≤ 600 mPa·S; the particle size of the aqueous polyolefin emulsion is < 300 nm, and it is sourced from Jiaxing Ruishi Chemical Industry, with a brand name of RS6799.

[0038] Water-based polyolefin emulsion-2: from Nanjing Tianshi New Materials, brand name Twax-7054.

[0039] Water-based polyolefin emulsion-3: from Shanghai Haoren International Trade, brand AC3100.

[0040] Diisopropyl di(acetylacetonate)titanate: Shanghai Huiyan New Materials, brand HY-AA-75.

[0041] Photoinitiator: 2-methyl-1-(4-methylthiophenyl)-2-morpholinyl-1-propanone.

[0042] Wetting agent: brand BYK346, purchased from BYK.

[0043] Defoaming agent: brand 902w, purchased from Digo.

[0044] Leveling agent: brand BYK-348, purchased from BYK.

[0045] Quick-drying agent: propylene glycol methyl ether.

[0046] Matting agent: Tosoh Silica Co., Ltd., brand E-1011.

[0047] Pigment: Phthalocyanine Blue BGS.

[0048] Unless otherwise specified, the components, raw materials or instruments used in the embodiments and comparative examples of the present invention are all commercially available raw materials or instruments, and the components and raw materials used in each parallel experiment are all of the same kind.

[0049] The following examples are provided to facilitate understanding of the present invention. These examples are not provided to limit the scope of the claims.

[0050] Examples 1 to 6, Comparative Examples 1 to 9

[0051] The formulas of the water-based UV insulating coatings for the aluminum-plastic films of the soft-pack batteries of Examples 1 to 6 and Comparative Examples 1 to 9 are shown in Table 1 (all percentages are in weight).

[0052] The preparation methods of the aqueous UV insulating coatings for the aluminum-plastic films of soft-pack batteries of Examples 1 to 6 and Comparative Examples 1 to 9 all include the following steps:

[0053] The water-based UV resin, the water-based polyolefin emulsion, the photoinitiator, the auxiliary agent, the quick-drying agent, the pigment and the water are uniformly mixed to obtain the water-based UV insulating coating for the aluminum-plastic film of the soft-pack battery.

[0054] Table 1

[0055]

[0056]

[0057] Performance Testing

[0058] The performance of the water-based UV insulating coating obtained in the above examples and comparative examples was characterized, and the specific test items, test methods and results are as follows:

[0059] The above water-based UV insulating coating was sprayed onto the surface of the nylon layer of the aluminum-plastic film of the soft-pack battery filled with electrolyte and treated with laser plasma, and dried at 55°C for 2 minutes until the water evaporated, and the dry film thickness was 15±0.5um. Then, the coating was heated at 1200mJ / cm 2 The film is cured under ultraviolet light.

[0060] Adhesion was measured according to GB / T9286-1998, where the lower the grade value, the better the adhesion; voltage breakdown resistance was tested using a voltage breakdown tester BDJC-50KV in accordance with GB / T 1695-2005; solvent resistance (95% ethanol) was tested using a BGD friction tester at a pressure of 500g and 30 times for 1 minute to perform a back-and-forth friction test, and the coating discoloration was observed; salt spray resistance (10% NaCl solution) was tested using a BGD friction tester at a pressure of 500g and 30 times for 1 minute to perform a back-and-forth friction test, and the coating discoloration was observed. The test results are shown in Table 2.

[0061] Table 1

[0062]

[0063]

[0064] It can be seen from Table 2 that the water-based UV insulating coating of the present invention has excellent electrical insulation performance, corrosion resistance and adhesion, and also has excellent bonding and adhesion performance, and has good adhesion on the aluminum-plastic film, which greatly improves the yield rate of the soft-pack battery.

[0065] By comparing Examples 2 to 3 with Examples 1 to 4, it can be seen that by controlling the weight ratio of the aqueous UV resin to the aqueous polyolefin emulsion to (5 to 9):1, the electrical insulation performance, corrosion resistance and adhesion are further improved.

[0066] It can be seen from the comparison of Examples 2, 5 to 6 and Comparative Examples 1 to 2 that the present invention further improves the electrical insulation performance, corrosion resistance and adhesion by controlling the amount of the photoinitiator within the scope of the present invention.

[0067] By comparing Example 2 with Comparative Examples 5 to 7, it can be seen that the present invention adopts a difunctional aliphatic polyurethane acrylate oligomer dispersion as the water-based UV resin, and controls its viscosity at 25°C to 80 to 140 mPa·S, and the pH value of the water-based UV resin is 7.4 to 7.6, which effectively improves the electrical insulation performance, corrosion resistance and adhesion.

[0068] By comparing Example 2 with Comparative Examples 8 to 9, it can be seen that the water-based polyolefin emulsion brand RS6799 used in the present invention effectively improves the electrical insulation performance, corrosion resistance and adhesion.

[0069] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A water-based UV insulating coating for aluminum-plastic film of soft-pack batteries, characterized in that: The invention comprises the following components in weight percentage: 50-80% water-based UV resin, 5-15% water-based polyolefin emulsion, 0.5-3% diisopropyl di(acetylacetonate)titanate, 2-6% photoinitiator, 0.5-3% auxiliary agent, 2-8 quick-drying agent, 0-6% matting agent, 0-15% pigment, and 0-10% water; The water-based UV resin is a difunctional aliphatic polyurethane acrylate oligomer dispersion.

2. The water-based UV insulating coating for the aluminum-plastic film of the soft-pack battery according to claim 1, characterized in that: The viscosity of the water-based UV resin at 25° C. is 80 to 140 mPa·S, and the pH value of the water-based UV resin is 7.4 to 7.

6.

3. The water-based UV insulating coating for the aluminum-plastic film of the soft-pack battery according to claim 1, characterized in that: The viscosity of the aqueous polyolefin emulsion at 25° C. is ≤600 mPa·S; and the particle size of the aqueous polyolefin emulsion is <300 nm.

4. The water-based UV insulating coating for the aluminum-plastic film of the soft-pack battery according to claim 1, characterized in that: The weight ratio of the water-based UV resin to the water-based polyolefin emulsion is (5-9):

1.

5. The water-based UV insulating coating for the aluminum-plastic film of the soft-pack battery according to claim 1, characterized in that: The photoinitiator includes at least one of 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1-(4-methylthiophenyl)-2-morpholinyl-1-propanone, 2-hydroxy-2-methylpropiophenone, and phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide.

6. The water-based UV insulating coating for the aluminum-plastic film of the soft-pack battery according to claim 1, characterized in that: The auxiliary agent includes at least one of a leveling agent, a defoaming agent and a wetting agent.

7. The water-based UV insulating coating for the aluminum-plastic film of the soft-pack battery according to claim 1, characterized in that: The quick-drying agent includes at least one of propylene glycol methyl ether, dipropylene glycol methyl ether and ethanol; The matting agent includes at least one of fumed silica and precipitated silica; The pigment includes at least one of Pigment Red 254, Phthalocyanine Blue BGS, carbon black, titanium dioxide, iron red, and iron black.

8. The method for preparing the water-based UV insulating coating for the aluminum-plastic film of the soft-pack battery according to any one of claims 1 to 7, characterized in that: The following steps are involved: The water-based UV resin, the water-based polyolefin emulsion, the photoinitiator, the auxiliary agent, the quick-drying agent, the pigment and the water are uniformly mixed to obtain the water-based UV insulating coating for the aluminum-plastic film of the soft-pack battery.

9. Application of the water-based UV insulating coating for the aluminum-plastic film of soft-pack batteries according to any one of claims 1 to 7 in the field of corrosion protection and insulation of soft-pack batteries.

10. The use according to claim 9, characterized in that: The electrolyte is filled into the soft-pack battery, and the surface of the nylon layer of the soft-pack battery aluminum-plastic film is coated with water-based UV insulating coating, which is baked at 50-60°C until the water evaporates, and then cured into a film under ultraviolet light to form an anti-corrosion insulating coating.

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