A coating liquid with high adhesion for ETFE film

Abstract

The present invention relates to the technical field of ETFE film, in particular to a coating liquid with high adhesion for ETFE film, which comprises the following components by weight: 20-40 parts of N-methylpyrrolidone, 20-40 parts of low-boiling solvent, 10-30 parts of vinylpyrrolidone, 10-30 parts of polyfunctional vinyl crosslinking agent, 10-30 parts of long-chain monofunctional acrylate, 0.5-9 parts of silane coupling agent, 0.5-9 parts of photoinitiator, and 100 parts of polyfunctional acrylic resin. Through the synergistic effect of N-methylpyrrolidone, vinylpyrrolidone, silane coupling agent, long-chain acrylate, etc., the present invention can improve the adhesion between ETFE and EVA film.

Description

Technical Field

[0001] The present invention relates to the technical field of ETFE films, and in particular to a coating liquid with high adhesion for ETFE films. Background Art

[0002] Due to good light transmittance and weather resistance, ETFE (ethylene-tetrafluoroethylene) films have great application potential, such as lightweight photovoltaic modules, etc. However, ETFE films are difficult to bond, and the adhesion force is generally < 5 N / CM; this limits its application. Therefore, how to solve the bonding problem of ETFE films has become a research hotspot in the industry. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a coating liquid with high adhesion for ETFE films to solve the above problems.

[0004] To solve the above technical problem, the technical solution adopted by the present invention is: a coating liquid with high adhesion for ETFE films, comprising the following components in parts by weight:

[0005] N-methylpyrrolidone 20 - 40 parts

[0006] Low-boiling solvent 20 - 40 parts

[0007] Vinylpyrrolidone 10 - 30 parts

[0008] Polyfunctional vinyl crosslinking agent 10 - 30 parts

[0009] Long-chain monofunctional acrylate 10 - 30 parts

[0010] Silane coupling agent 0.5 - 9 parts

[0011] Photoinitiator 0.5 - 9 parts

[0012] Polyfunctional acrylic resin 100 parts.

[0013] As a further aspect of the present invention, the low-boiling solvent is one or more of methanol, ethanol, ethyl acetate, butanone, cyclohexane, methylcyclohexane, and petroleum ether.

[0014] As a further aspect of the present invention, the polyfunctional vinyl crosslinking agent is one or more of TAIC, TMPTA, ethoxylated TMPTA, propoxylated TMPTA, and hexanediol diacrylate.

[0015] As a further aspect of the present invention, the long-chain monofunctional acrylate is isooctyl acrylate, lauryl acrylate, stearyl acrylate, n-butyl acrylate, isobutyl acrylate, or tert-butyl acrylate.

[0016] As a further solution of the present invention, the silane coupling agent is KH570 or KH171.

[0017] As a further solution of the present invention, the photoinitiator is photoinitiator 184 or photoinitiator 1173.

[0018] As a further solution of the present invention, it includes an immersion liquid, and the immersion liquid consists of the following components by weight:

[0019]

[0020] As a further solution of the present invention, the low-boiling and low-polarity solvent is one or more of methylcyclohexane, cyclohexane, n-hexane, or petroleum ether.

[0021] Since the present invention adopts the above technical solutions, the advantages and positive effects of the present invention are:

[0022] 1. N-methylpyrrolidone and vinylpyrrolidone have a dissolving and wetting effect on ETFE, which can improve its adhesiveness;

[0023] 2. The silane coupling agent undergoes a cross-linking reaction with the silane in the EVA film formulation, thereby improving the adhesion between ETFE and the EVA film;

[0024] 3. The long-chain acrylate has a similar and compatible carbon chain structure with ETFE, which can improve the adhesiveness of ETFE. Specific Embodiments

[0025] A coating liquid with high adhesiveness for an ETFE film of the present invention includes the following components by weight:

[0026]

[0027] N-methylpyrrolidone plays a role in dissolving and wetting ETFE; the low-boiling solvent plays a role in driving the volatilization of N-methylpyrrolidone; the multi-functional vinyl cross-linking agent plays a role in cross-linking to form a film; the long-chain acrylate plays a role in wetting ETFE and forming a film; vinylpyrrolidone plays a role in wetting ETFE and forming a film; the acrylic resin plays a role in providing viscosity and forming a film; the silane coupling agent plays a role in bonding with the adhesive layer.

[0028] Among them, the low-boiling solvent is one or more of methanol, ethanol, ethyl acetate, butanone, cyclohexane, methylcyclohexane, or petroleum ether.

[0029] Among them, the multi-functional vinyl cross-linking agent is one or more of TAIC, TMPTA, ethoxylated TMPTA, propoxylated TMPTA, or hexanediol diacrylate.

[0030] Among them, the long-chain monofunctional acrylate is isooctyl acrylate or lauryl acrylate or stearyl acrylate or n-butyl acrylate or isobutyl acrylate or tert-butyl acrylate.

[0031] Among them, the silane coupling agent is KH570 or KH171.

[0032] Among them, the photoinitiator is photoinitiator 184 or photoinitiator 1173.

[0033] Furthermore, the present invention also includes an immersion liquid, and the immersion liquid consists of the following components by weight:

[0034]

[0035] Among them, the low-boiling and low-polarity solvent is one or several of methylcyclohexane or cyclohexane or n-hexane or petroleum ether.

[0036] Furthermore, the usage method of the present invention is as follows: Before applying the coating liquid on the ETFE film, apply the immersion liquid, and then dry it at 120 °C after coating the coating liquid, and perform UV curing. The immersion liquid can promote the adhesion of the coating liquid to the ETFE.

[0037] Example 1

[0038] Based on 100 parts of the polyfunctional acrylic resin: X parts of N-methylpyrrolidone, Y parts of ethyl acetate, Z parts of vinylpyrrolidone, 20 parts of TAIC, 20 parts of octyl acrylate, 2 parts of the silane coupling agent KH570, 1.5 parts of the photoinitiator 184; dry it at 120 °C after coating, and perform UV curing, and test the adhesion to the EVA film.

[0039] In the examples, the addition amounts, adhesive forces, processabilities of the coating liquid, and UV curing performance data of N-methylpyrrolidone, ethyl acetate, and vinylpyrrolidone are shown in Table 1

[0040]

[0041]

[0042] Table 1

[0043] As can be seen from Table 1, since N-methylpyrrolidone has a dissolving and wetting effect on ETFE and can improve its adhesion, but due to its high boiling point, it is not easy to dry when it is more than 40 parts; so it is necessary to heat the low-boiling solvent, but when ethyl acetate is added to 50 parts, the viscosity of the coating liquid is too low and bleeding phenomenon occurs; since vinylpyrrolidone has a dissolving and wetting effect on ETFE and can improve the adhesive force, but the UV polymerization rate of its double bond is relatively slow, and when it is increased to 30 parts, it cannot be completely cured.

[0044] Example 2

[0045] Based on 100 parts of the multifunctional acrylic resin: 30 parts of N-methylpyrrolidone, 30 parts of ethyl acetate, 20 parts of vinylpyrrolidone, 20 parts of TAIC, 1.5 parts of photoinitiator 184; after coating, dry at 120 °C and cure by UV, then test the adhesion to the EVA film.

[0046] The addition amounts, adhesive forces, processabilities of the coating liquids, and UV curing performance data of KH570 and KH171 in the examples are shown in Table 2.

[0047]

[0048]

[0049] Table 2

[0050] As can be seen from Table 2, the silane coupling agent can improve the adhesion between ETFE and the EVA film. The main reason is that it can crosslink with the silane in the EVA film formulation. However, due to the methyl group on the acrylate bond of KH570, the UV curing is slow, and when added to 15 parts, the UV cannot completely cure; the steric hindrance of the side chain of KH171 is very large, and when added to 9 parts, the UV curing is incomplete.

[0051] Example 3

[0052] Based on 100 parts of the multifunctional acrylic resin: 30 parts of N-methylpyrrolidone, 30 parts of ethyl acetate, 20 parts of vinylpyrrolidone, 20 parts of TAIC, 2 parts of KH570, 1.5 parts of photoinitiator 184; after coating, dry at 120 °C and cure by UV, then test the adhesion to the EVA film.

[0053] The addition amounts, adhesive forces, processabilities of the coating liquids, and UV curing performance data of the additives in the examples are shown in Table 3.

[0054]

[0055] Table 3

[0056] As can be seen from Table 3, due to the long carbon chain acrylate, the carbon chain structure is similar and compatible with ETFE, so the adhesion of ETFE can be improved; however, the free radicals of the long carbon chain acrylate are easily entrapped, and the UV curing is slow, so the UV of lauryl acrylate and octadecyl acrylate cannot completely cure, and 30 parts of isooctyl acrylate also cannot completely cure.

[0057] Example 4

[0058] The soaking solution consists of 90 parts of cyclohexane, 10 parts of methylcyclohexane, 30 parts of N-methylpyrrolidone, X parts of ETFE, Y parts of SBS, and Z parts of petroleum resin; after the soaking solution is coated, it is preliminarily dried, and a UV coating solution is applied. The coating solution consists of 100 parts of multifunctional acrylic resin: 30 parts of N-methylpyrrolidone, 30 parts of ethyl acetate, 20 parts of vinylpyrrolidone, 20 parts of TAIC, 2 parts of KH570, 20 parts of n-butyl acrylate, and 1.5 parts of photoinitiator 184; after coating, it is dried at 120 °C and UV cured, and the adhesion to the EVA film is tested.

[0059] In the examples, the appearance and adhesion data of ETFE, SBS, and petroleum resin are shown in Table 4

[0060]

[0061] Table 4

[0062] As can be seen from Table 4, the soaking solution can promote the adhesion of the UV coating layer to ETFE. Due to the principle of similar compatibility, adding ETFE particles can improve the adhesion, but when added to 8 parts, it cannot be completely dissolved, so the soaking solution becomes turbid. Adding SBS resin can also improve the adhesion, but when it reaches 15 parts, it cannot be completely dissolved. Petroleum tackifying resin is a small carbon chain molecule with polar groups such as hydroxyl and carboxyl groups. Adding petroleum tackifying resin can also improve the adhesion and has good solubility, but due to being a small molecule, the film-forming property of the soaking solution decreases, so when added to 8 parts, the adhesion decreases instead.

[0063] Although the specific embodiments of the present invention have been described above, those skilled in the art should understand that these are only examples, and various changes or modifications can be made to these embodiments without departing from the principles and essence of the present invention. The protection scope of the present invention is only defined by the appended claims.

Claims

1. A coating liquid with high adhesion for ETFE film, characterized in that: It comprises the following components by weight parts: 20 - 30 parts of N-methylpyrrolidone 20 - 40 parts of low-boiling solvent 20 parts of vinylpyrrolidone 10 - 30 parts of polyfunctional vinyl crosslinking agent 20 parts of long-chain monofunctional acrylate 0.5 - 5 parts of silane coupling agent 0.5 - 9 parts of photoinitiator 100 parts of polyfunctional acrylic resin; The coating solution is used in combination with the immersion solution, and the immersion solution comprises the following components by weight parts: 20 - 50 parts of N-methylpyrrolidone 1 - 5 parts of ETFE resin 3 - 10 parts of SBS resin 1 - 5 parts of petroleum tackifying resin 100 parts of low-boiling low-polarity solvent; The low-boiling solvent is ethyl acetate; the long-chain monofunctional acrylate is n-butyl acrylate or isobutyl acrylate or tert-butyl acrylate; the silane coupling agent is KH570 or KH171.

2. The coating liquid with high adhesion force for ETFE film according to claim 1, characterized in that: The polyfunctional vinyl crosslinking agent is one or more of TAIC or TMPTA or ethoxylated TMPTA or propoxylated TMPTA or hexanediol diacrylate.

3. The coating liquid with high adhesion force for ETFE film according to claim 1 is characterized in that: The photoinitiator is photoinitiator 184 or photoinitiator 1173.

4. The coating liquid with high adhesion force for ETFE film according to claim 1 is characterized in that: The low-boiling low-polarity solvent is one or more of methylcyclohexane or cyclohexane or n-hexane or petroleum ether.

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