New-form protection material and preparation method and application thereof

Abstract

The invention discloses a novel-form protective material and a preparation method and application thereof, the novel-form protective material comprises a carrier film, a washing-removable photosensitive resin layer and a cover film which are stacked in sequence, the washing-removable photosensitive resin layer comprises washing-removable photosensitive resin and a curing agent, the surface dry hardness SH of the washing-removable photosensitive resin layer is smaller than 8B, and the softening temperature TS is larger than or equal to 30 DEG C and smaller than 60 DEG C. The protective material provided by the invention has the advantages of high hardness and high cohesive force, the protective material is attached to the surface of a workpiece for curing during machining, and the protective material is relatively high in hardness and clings to the workpiece, so that the purposes of improving machining burrs and preventing the workpiece from being scratched can be achieved; meanwhile, the protective material provided by the invention can realize complete film stripping after application, and film stripping residues are avoided.

Description

Technical Field

[0001] This invention belongs to the field of workpiece protection technology, specifically relating to a novel protective material, its preparation method, and its application. Background Technology

[0002] In recent years, with the rapid development of the electronics industry, many electronic products have increasingly higher requirements for the manufacturing of metal and glass workpieces. When drilling, punching, milling and other machining processes are performed on the workpieces, they are easily scratched and produce large burrs, which affects their use. Therefore, it is necessary to coat the surface of the workpieces to be processed with a temporary protective film to prevent the parts from being scratched and to inhibit the generation of burrs. The temporary protective film is removed after processing.

[0003] Traditional temporary protective films are applied to the workpiece surface using adhesives to prevent damage or scratches, providing temporary protection. However, they are usually quite soft and have weak adhesion, making them ineffective at suppressing burrs during machining operations such as drilling, milling, and punching. Furthermore, they require manual removal, posing a risk of residual adhesive. Alternatively, a washable coating can be applied to the workpiece surface. This protects the surface from scratches and provides some burr suppression during machining operations such as drilling, milling, and punching. However, if there are gaps in the workpiece, the coating can easily get trapped in these gaps, making it difficult to remove and affecting workpiece quality.

[0004] Therefore, there is a need for a protective film that has high hardness, can suppress burrs, provide protection, and is easy to peel off without leaving residue to meet application requirements. Summary of the Invention

[0005] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a new type of protective material, its preparation method and application.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a novel protective material comprising a carrier film, a washable photosensitive resin layer, and a cover film stacked sequentially. The washable photosensitive resin layer comprises a washable photosensitive resin and a curing agent. The surface dry hardness SH of the washable photosensitive resin layer is <8B, and the softening temperature T is [missing information]. S For 30℃≤T S <60℃.

[0008] The novel protective material provided by this invention has the following advantages:

[0009] i. After surface drying, it has a certain hardness and a softening temperature above room temperature, meaning it is not fluid after surface drying and can be molded at room temperature. In application, it can be directly bonded to the surface of the workpiece without melting, thus avoiding the flow of melt into the gaps of the workpiece (such as blind holes in PCBs), thereby avoiding the defects of residual film removal in the future.

[0010] ii. Excellent adhesion to metals allows the new protective material to adhere tightly to the workpiece after curing. This not only prevents the protective film from peeling off and allows it to fully perform its function, but also effectively suppresses wire drawing and other phenomena during machining processes such as drilling, milling, and punching.

[0011] iii. It has a high hardness after curing, so it can improve the appearance of burrs and prevent scratches during workpiece processing;

[0012] iv. It is washable and can be washed with a washing solution. The washing method is simple and does not require manual peeling. Since the new protective material does not enter the gaps of the workpiece, complete film removal can be achieved. The process is simple and convenient.

[0013] v. The novel form described in this invention refers to the protective material being in the form of a semi-solid adhesive film, which can be wound up and other operations, and can be stored and transported in roll form.

[0014] Therefore, the novel protective material provided by this invention has the advantages of high hardness and high adhesion. When machining, the novel protective material is adhered to the surface of the workpiece and cured. The novel protective material has high hardness and adheres tightly to the workpiece, which can improve the processing burrs and prevent the workpiece from being scratched. At the same time, it can achieve complete film removal after application without any film removal residue. The process is simple and easy to implement.

[0015] In this invention, the surface dry hardness of the washable photosensitive resin layer <8B can be 9B, 10B, etc., and the 30℃≤T S <60℃ can be 30℃, 40℃, 42℃, 45℃, 48℃, 50℃, 52℃, 55℃, 58℃, 59℃, etc.

[0016] Preferably, the washable photosensitive resin layer further comprises a thermoplastic resin, wherein the softening temperature T of the thermoplastic resin is... S For 30℃≤T S <60℃, for example 30℃, 40℃, 42℃, 45℃, 48℃, 50℃, 52℃, 55℃, 58℃, 59℃, etc. Preferably, the hardness of the washable photosensitive resin layer after UV curing is ≥5 B, for example 4B, 3B, 2B, B, HB, H, 2H, 3H, 4H, 5H, 6H, etc.

[0017] Preferably, the metal adhesion of the washable photosensitive resin layer is ≤ level 3, such as level 3, level 2, level 1 or level 0.

[0018] Preferably, the thickness of the washable photosensitive resin layer is 20-300 μm, such as 20 μm, 30 μm, 50 μm, 100 μm, 150 μm, 200 μm, 250 μm, 300 μm, etc.

[0019] In this invention, if the surface hardness of the washable photosensitive resin layer is too high, it is not conducive to low-temperature bonding and is easy to fall off. If the hardness of the washable photosensitive resin layer after UV curing is too low, the protective effect is poor and the workpiece is still at risk of being easily scratched. If the coating of the washable photosensitive resin layer has poor adhesion to the metal, there is a risk of it falling off during use.

[0020] In this invention, the hardness is obtained by testing according to the test method of GB / T 6739-2022 "Determination of Hardness of Paint Film by Pencil Method".

[0021] In this invention, the softening temperature is tested using the TMA method.

[0022] In this invention, the metal bonding strength is obtained by testing according to the test method of GB / T 9286-2021 "Cross-cut test for paints and varnishes", wherein the metal is copper foil.

[0023] Preferably, the washable photosensitive resin layer comprises, by weight:

[0024] 20-90 parts washable photosensitive resin, 1-50 parts thermoplastic resin, 1-40 parts filler, 1-10 parts photocuring agent and 0.1-5 parts processing aid.

[0025] In this invention, the washable photosensitive resin (20-90 parts) can be 20 parts, 30 parts, 40 parts, 50 parts, 60 parts, 70 parts, 80 parts, 85 parts, 90 parts, etc.; the thermoplastic resin (1-50 parts) can be 1 part, 5 parts, 10 parts, 15 parts, 20 parts, 25 parts, 30 parts, 40 parts, 50 parts, etc.; the filler (1-40 parts) can be 1 part, 5 parts, 10 parts, 15 parts, 20 parts, 25 parts, 30 parts, 35 parts, 40 parts, etc.; and the processing aid (0.1-5 parts) can be 0.1 parts, 0.5 parts, 1 part, 2 parts, 3 parts, 4 parts, 5 parts, etc.

[0026] Preferably, the washable photosensitive resin contains any one or a combination of at least two of amino, aldehyde, hydroxyl, carboxyl, amide, carbonyl, or ether groups. More preferably, the washable photosensitive resin is a modified or unmodified acrylate resin. More preferably, it includes any one or a combination of at least two of modified epoxy acrylate resin, modified polyurethane acrylate resin, modified polyester acrylate resin, or modified polyether acrylate resin.

[0027] Preferably, the thermoplastic resin includes any one or a combination of at least two of polyvinyl butyral, thermoplastic polyurethane, or solid thermoplastic acrylic.

[0028] Preferably, the photocuring agent comprises any one or a combination of at least two of the following: a pyrolytic free radical photoinitiator, a hydrogen-abstracting free radical photoinitiator, or a cationic photoinitiator. More preferably, it comprises 2-hydroxy-2-methyl-1-phenylpropanone (photocuring agent 1173), 1-hydroxycyclohexylphenyl methyl ketone (photocuring agent 184), 2-methyl-2-(4-morpholino)-1-[4-(methylthio)phenyl]-1-propanone (photocuring agent 907), 2,4,6-trimethylbenzoyl-diphenylphosphine oxide (photocuring agent TPO), methyl benzoylformate (photocuring agent MBF), and ethyl 2,4,6-trimethylbenzoyl-phenylphosphine oxide (photocuring agent TPO-L). More preferably, it comprises any one or a combination of at least two of the following: 2-hydroxy-2-methyl-1-phenylpropanone, 1-hydroxycyclohexylphenyl methyl ketone, and 2,4,6-trimethylbenzoyl-diphenylphosphine oxide.

[0029] Preferably, the filler comprises any one or a combination of at least two of talc, calcium carbonate, silica, barium sulfate, bentonite, or kaolin.

[0030] Preferably, the processing aids include leveling agents and / or defoamers.

[0031] Preferably, the carrier film includes any one or a combination of at least two of BOPP film, PET film, PC film, EVA film or OPP film, with PET film being the most preferred.

[0032] Preferably, the thickness of the carrier membrane is 0.01-0.15 mm, such as 0.01 mm, 0.05 mm, 0.1 mm, 0.15 mm, etc.

[0033] If the thickness of the carrier film is too small, the load-bearing capacity will be too small, which will not be conducive to subsequent bonding and the protection effect will be poor; if the thickness of the carrier film is too large, the bending resistance will be poor and the cost will be high.

[0034] Preferably, the thickness of the covering film is 0.01-0.15 mm, such as 0.01 mm, 0.05 mm, 0.1 mm, 0.15 mm, etc.

[0035] Preferably, the release force between the cover film and the washable photosensitive resin layer is ≤100 g / in, such as 100 g / in, 90 g / in, 80 g / in, 70 g / in, 60 g / in, 50 g / in, 40 g / in, 30 g / in, 20 g / in, 10 g / in, 1 g / in, etc.

[0036] In this invention, the introduction of a cover film protects the adhesive layer from contamination and damage, thereby reducing the probability of air bubbles and insufficient adhesive in subsequent bonding applications of the washable photosensitive resin layer, and preventing problems such as adhesive overflow during storage. If the release force of the cover film is too high, the release effect will be poor, and removing the cover film will damage the adhesive layer of the washable photosensitive resin layer; if the cover film is too thin, the protective effect will be poor, which is not conducive to the operation of removing the cover film during application; if the cover film is too thick, the bending resistance will be too poor and the cost will be high.

[0037] Preferably, the covering film includes any one or a combination of at least two of BOPP film, PET film, PC film, EVA film, OPP film or PE film, and preferably PET film.

[0038] In a second aspect, the present invention provides a method for preparing the novel protective material as described in the first aspect, the method comprising:

[0039] (1) A washable photosensitive resin layer, including a washable photosensitive resin and a curing agent, is coated onto a carrier film using a slurry;

[0040] (2) After surface drying, a cover film is placed on the washable photosensitive resin layer, and then the material is rolled up to obtain the new protective material.

[0041] Preferably, the coating method includes, but is not limited to, blade coating, spray coating, or roller coating.

[0042] Preferably, the surface drying method includes baking, room temperature, etc.

[0043] Thirdly, the present invention provides the application of a novel protective material as described in the first aspect as a protective film for workpiece processing.

[0044] Preferably, the method of application includes:

[0045] Remove the cover film of the new protective material, attach the washable photosensitive resin layer to the surface of the part to be protected, and perform UV curing. After curing, remove the carrier film to complete the setting of the new protective material.

[0046] After the protective component is processed, the new protective material is removed by soaking in a washing solution, thus completing the application of the new protective material.

[0047] The novel protective material described in this invention only requires bonding and curing. This method avoids the risk of the novel protective material flowing into the gaps of the workpiece due to melting and heating, which could easily lead to residual film during subsequent removal.

[0048] Preferably, the bonding temperature is greater than or equal to the softening temperature of the novel protective material, and is preferably 30-150℃, such as 30℃, 40℃, 50℃, 60℃, 70℃, 80℃, 90℃, 100℃, 120℃, 130℃, 140℃, 150℃, etc.; preferably, the pressure is 0.5-10 kgf / cm. 2 For example, 0.5 kgf / cm 2 1 kgf / cm 2 2 kgf / cm 2 3 kgf / cm 2 4 kgf / cm 2 5 kgf / cm 2 6 kgf / cm 2 7 kgf / cm 2 8 kgf / cm 2 9 kgf / cm 2 10 kgf / cm 2 wait.

[0049] In this invention, the bonding temperature should not be too high. If it is too high, the washable photosensitive resin layer will soften severely and enter the gaps in the workpiece, resulting in residual film removal. If the bonding pressure is too low, the adhesion between the washable photosensitive resin layer and the workpiece will be poor, and it will easily fall off during workpiece processing. If the bonding pressure is too high, the washable photosensitive resin layer will enter the gaps in the workpiece, resulting in residual film removal.

[0050] Preferably, the UV curing energy includes 300-4000 mJ / m². 2 For example, 300 mJ / cm 2 500 mj / cm 2 800 mj / cm 2 1000 mj / cm 2 1500 mj / cm 2 2000 mj / cm 2 2500 mj / cm 2 3000 mj / cm 2 3500 mj / cm2 4000 mj / cm 2 wait.

[0051] If the curing energy is too low, it may result in incomplete curing, and the cured washable photosensitive resin layer will be soft and have poor adhesion to the workpiece, which may cause burrs during drilling. If the curing energy is too high, it may cause bubbles to appear in the washable photosensitive resin layer, which will also affect the burr suppression effect.

[0052] Preferably, the stripping solution includes an alkaline stripping solution or water.

[0053] Preferably, the rinsing temperature of the rinsing solution is 20-100℃, such as 20℃, 30℃, 40℃, 50℃, 60℃, 70℃, 80℃, 90℃, 100℃, etc.; preferably, the rinsing temperature of the rinsing solution is 40-90℃.

[0054] Compared with the prior art, the present invention has the following beneficial effects:

[0055] (1) The novel protective material provided by the present invention has the advantages of high hardness and high adhesion. When machining, the novel protective material is attached to the surface of the workpiece and cured. The novel protective material has high hardness and is closely attached to the workpiece, which can achieve the purpose of improving machining burrs and preventing workpiece scratches.

[0056] (2) Meanwhile, the new protective material provided by the present invention can achieve complete film removal after application without film removal residue. Detailed Implementation

[0057] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention.

[0058] Unless otherwise specified, the raw materials involved in the following specific embodiments of the present invention are all conventional materials in the art, and can be purchased from commercially available products. Some raw material information is as follows:

[0059] Modified polyester acrylate 1: purchased from Guangdong Hengzhiguang Environmental Protection New Materials Co., Ltd., model number 52312A;

[0060] Modified polyester acrylate 2: purchased from Guangdong Haohui New Materials Co., Ltd., model number CR92284;

[0061] Modified epoxy acrylate 1: purchased from Dongguan Lanka Polymer Co., Ltd., model UR3109, UR3109-7;

[0062] Modified epoxy acrylate 2: purchased from Nanxiong Ketian Chemical Co., Ltd., model number 4421;

[0063] Modified polyurethane acrylate: purchased from Dongguan Jingshang New Materials Development Co., Ltd., model UV2637;

[0064] Polyvinyl butyral: purchased from Shanghai Yunhe Materials Technology Co., Ltd., model number BL-10;

[0065] Solid thermoplastic acrylic: purchased from Shanghai Qizhan New Material Technology Co., Ltd., model B514;

[0066] PET film: 0.03 mm, purchased from Huizhou Best Film Industry Co., Ltd., model is ordinary 0.03 mm PET film;

[0067] PE film: release force 60 g / in, 0.02 mm, purchased from Shenzhen Zechang Electronic Materials Co., Ltd., model 60 g 0.02 mm PE release film;

[0068] PET film: release force 30 g / in, 0.02 mm, purchased from Huizhou Best Film Co., Ltd., model 30 g 0.02 mm PET release film;

[0069] BOPP film: release force 50 g / in, 0.025 mm, purchased from Yiwu Hongfeng Packaging Products Co., Ltd., model 50g 0.025mm BOPP film.

[0070] Examples 1-5

[0071] This embodiment provides a novel protective material, its preparation method, and its application, as follows:

[0072] (1) Mix the components according to Table 1 to obtain a washable photosensitive resin layer slurry;

[0073] (2) Take a cover film (PET film, 0.03 mm), coat the washable photosensitive resin layer onto the carrier film with slurry, and let it dry on the surface;

[0074] (3) After the surface is dry, a cover film is attached and the material is rolled up to obtain the new protective material.

[0075] When applying it:

[0076] S1. Unwind, remove the cover film, attach the washable photosensitive resin layer to the surface of the workpiece to be protected, and perform UV curing. After curing, remove the carrier film to complete the setting of the new protective material.

[0077] S2. After the workpiece to be protected is processed, use a stripping solution to soak and remove the new protective material, thus completing the application of the new protective material.

[0078] The composition parameters and processing parameters of the paste for washable photosensitive resin layers are shown in Table 1:

[0079] Table 1

[0080]

[0081] Performance testing:

[0082] The performance of the novel protective materials provided in Examples 1-5 was tested using the following methods:

[0083] (1) Hardness: Tested according to the test method of GB 6739-86 "Coating Hardness Pencil Hardness Method";

[0084] (2) Metal bonding strength: Tested according to the test method of GB / T 9286-2021 "Paints and Varnishes Cross-cut Test", with copper foil as the metal;

[0085] (3) Burrs: The test method is microscopic measurement; among them, when there is no protective film, the burr of the workpiece is 75.4 μm;

[0086] (4) Residual film removal rate: visual inspection method;

[0087] The test results are as follows:

[0088] Table 2

[0089]

[0090] As can be seen from the examples and performance tests, the novel protective material provided by the present invention has high hardness and high bonding force with the workpiece. After curing, it can be tightly bonded to the workpiece, which can prevent scratches on the workpiece during processing and play a good protective role. Moreover, the protective film is not easy to fall off during processing. After application, it can be completely removed by washing with a stripping solution, leaving no residue.

[0091] The applicant declares that the technical solution of this invention is illustrated through the above embodiments, but this invention is not limited to the above process steps, that is, it does not mean that this invention must rely on the above process steps to be implemented. Those skilled in the art should understand that any improvements to this invention, equivalent substitutions of the raw materials used in this invention, additions of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of this invention.

Claims

1. A novel protective material, characterized in that, The film comprises a carrier film, a washable photosensitive resin layer, and a cover film stacked sequentially. The washable photosensitive resin layer consists of a washable photosensitive resin and a curing agent. The surface dry hardness SH of the washable photosensitive resin layer is less than 8B, and the softening temperature T is... S For 30℃≤T S <60℃.

2. The novel protective material according to claim 1, characterized in that, The washable photosensitive resin layer also includes a thermoplastic resin, the softening temperature T of which is... S For 30℃≤T S <60℃; Preferably, the hardness of the washable photosensitive resin layer after UV curing is ≥5 B; Preferably, the metal adhesion of the washable photosensitive resin layer is ≤ level 3; Preferably, the thickness of the washable photosensitive resin layer is 20-300 μm; Preferably, the novel protective material has a roll-like structure.

3. The novel protective material according to claim 1 or 2, characterized in that, The washable photosensitive resin layer comprises, by weight, the following: 20-90 parts washable photosensitive resin, 1-50 parts thermoplastic resin, 1-40 parts filler, 1-10 parts photocuring agent and 0.1-5 parts processing aid.

4. The novel protective material according to claim 3, characterized in that, The washable photosensitive resin contains any one or a combination of at least two of amino, aldehyde, hydroxyl, carboxyl, amide, carbonyl or ether groups. Preferably, the washable photosensitive resin is a modified or unmodified acrylate resin, and more preferably includes modified epoxy acrylate resin, modified polyurethane acrylate resin, or modified polyester acrylate resin. Preferably, the thermoplastic resin includes any one or a combination of at least two of polyvinyl butyral, thermoplastic polyurethane, or solid thermoplastic acrylic. Preferably, the photocuring agent comprises any one or a combination of at least two of the following: a pyrolytic free radical photoinitiator, a hydrogen-abstracting free radical photoinitiator, or a cationic photoinitiator. More preferably, it comprises 2-hydroxy-2-methyl-1-phenylpropanone, 1-hydroxycyclohexylphenyl ketone, 2-methyl-2-(4-morpholino)-1-[4-(methylthio)phenyl]-1-propanone, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, methyl benzoylformate, and ethyl 2,4,6-trimethylbenzoyl-phenylphosphine. More preferably, it comprises any one or a combination of at least two of the following: 2-hydroxy-2-methyl-1-phenylpropanone, 1-hydroxycyclohexylphenyl ketone, and 2,4,6-trimethylbenzoyl-diphenylphosphine oxide. Preferably, the filler comprises any one or a combination of at least two of talc, calcium carbonate, silica, barium sulfate, bentonite, or kaolin. Preferably, the processing aids include leveling agents and / or defoamers.

5. The novel protective material according to any one of claims 1-4, characterized in that, The carrier film includes any one or a combination of at least two of BOPP film, PET film, PC film, EVA film or OPP film, preferably PET film; Preferably, the thickness of the carrier membrane is 0.01-0.15 mm.

6. The novel protective material according to any one of claims 1-5, characterized in that, The thickness of the covering film is 0.01-0.15 mm; Preferably, the release force between the cover film and the washable photosensitive resin layer is ≤100 g / in; Preferably, the covering film includes any one or a combination of at least two of BOPP film, PET film, PC film, EVA film, OPP film or PE film, and preferably PET film.

7. A method for preparing a novel protective material as described in any one of claims 1-6, characterized in that, The preparation method includes: (1) A washable photosensitive resin layer, including a washable photosensitive resin and a curing agent, is coated onto a carrier film using a slurry; (2) After surface drying, a cover layer is set on the washable photosensitive resin layer, and then the material is wound up to obtain the new protective material.

8. The application of a novel protective material as described in any one of claims 1-6 as a protective film for workpiece processing; Preferably, the method of application includes: Remove the covering layer of the new protective material, attach the washable photosensitive resin layer to the surface of the part to be protected, and perform UV curing. After curing, remove the carrier film to complete the setting of the new protective material. After the protective component is processed, the new protective material is removed by soaking in a washing solution, thus completing the application of the new protective material.

9. The application according to claim 8, characterized in that, The bonding temperature is greater than or equal to the softening temperature of the novel protective material; preferably, the UV curing energy includes 300-4000 mJ / m². 2 .

10. The application according to claim 8 or 9, characterized in that, The film-removing solution includes an alkaline washing solution or water; Preferably, the rinsing temperature of the rinsing solution is 20-100℃, and more preferably 40-90℃.

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