Residue-free ultraviolet curing peelable glue as well as preparation method and application thereof
By selecting polyurethane-modified acrylate resin of appropriate viscosity and a reasonable ratio of photoinitiator and thixotropic agent, a residue-free UV-curable peelable adhesive was prepared, solving the problem of substrate surface contamination in the prior art and achieving traceless peeling and good operability.
Patent Information
- Application Number
- CN202511171091.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-21
- Publication Date
- 2025-11-11
AI Technical Summary
Existing UV-curable peelable adhesives tend to leave traces of small molecule additives and reactive diluents during the peeling process, resulting in contamination of the substrate surface and affecting production efficiency and product yield.
By selecting an appropriate viscosity range (3000-150000 mPa.s) for polyurethane-modified acrylate resin and a reasonable ratio of liquid and solid photoinitiators, combined with thixotropic agents and colorants, a residue-free UV-curable peelable adhesive is prepared, ensuring complete curing and residue-free peeling.
It achieves a peeling effect without leaving any residue, improves production efficiency and product yield, and maintains good adhesive workability and flexibility.
Smart Images
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Abstract
Description
Technical Field
[0001] This invention belongs to the field of electronic materials, specifically relating to a residue-free UV-curable peelable adhesive, its preparation method, and its application. Background Technology
[0002] UV-curable peelable adhesive is a temporary bonding and protective material that cures rapidly under ultraviolet light. It features fast curing speed, environmental friendliness (solvent-free), and easy peeling without leaving residue. Under UV light (typically 365nm or 395nm wavelength), the adhesive forms a solid layer within seconds to minutes. After curing, it retains its flexibility, facilitating complete peeling. It is suitable for temporary fixation of electronic components, PCB protection, precision machining surface protection, and optical device assembly. Its peelable nature makes it crucial in processes requiring non-permanent bonding or protection, providing reliable temporary fixation and easy removal after protection or assembly, significantly improving production efficiency and product yield.
[0003] To achieve good peelability, existing UV-curable peelable adhesives require the addition of small-molecule additives to reduce peel force. Additionally, to achieve specific viscosity or mechanical properties, a significant amount of reactive diluents, i.e., acrylate monomers, is added. When these small molecules in the peelable adhesive come into contact with the substrate requiring temporary protection / bonding, they rapidly wet / penetrate along the substrate surface. During the removal process after the adhesive has cured, they cannot be completely peeled off with the adhesive body, leaving marks on the substrate surface and causing contamination.
[0004] Therefore, existing technologies urgently need to be addressed. Summary of the Invention
[0005] This invention aims to address the shortcomings of existing technologies by providing a residue-free UV-curable peelable adhesive, its preparation method, and its applications. The residue-free UV-curable peelable adhesive provided by this invention solves the problem of product surface contamination caused by the removal of adhesive after temporary protection or bonding with peelable adhesives.
[0006] To address the above problems, the present invention provides the following technical solution: A residue-free UV-curable peelable adhesive is mainly prepared from the following raw materials in parts by weight: 90-99 parts of polyurethane-modified acrylate resin and 1-8 parts of photoinitiator; wherein the viscosity of the polyurethane-modified acrylate resin at room temperature is 3000-150000 mPa·s. Under these conditions, experiments have shown that if the viscosity of the polyurethane-modified acrylate resin is below 3000 mPa·s, it will easily penetrate into the micropores of the substrate due to its high fluidity, resulting in residue problems; if the viscosity is above 150000 mPa·s, it will have poor workability and uneven application due to poor fluidity. Preferably, the residue-free UV-curable peelable adhesive is mainly prepared from the following raw materials in parts by weight: 90.5-93.99 parts of polyurethane-modified acrylate resin and 5-6 parts of photoinitiator; wherein the viscosity of the polyurethane-modified acrylate resin at room temperature is 5000-110000 mPa·s. Most preferably, the viscosity of the polyurethane-modified acrylate resin at room temperature is 110000 mPa·s.
[0007] The residue-free UV-curable peelable adhesive described above includes at least one liquid photoinitiator that is liquid at room temperature. Under these conditions, the photoinitiator can be completely dissolved, allowing for thorough mixing with other components.
[0008] The residue-free UV-curable peelable adhesive described above uses a liquid photoinitiator selected from any one or a mixture of several of 2-hydroxy-2-methylphenylacetone (i.e., photoinitiator 1173), ethyl (2,4,6-trimethylbenzoyl)phenylphosphonate (i.e., liquid photoinitiator TPO-L), and bis(2,6-difluoro-3-pyrrolephenyl)bis(2,4,6-trimethylbenzoyl)phosphine oxide (i.e., liquid photoinitiator BAPO-L). Preferably, the liquid photoinitiator is selected from either photoinitiator 1173 or liquid photoinitiator TPO-L, under which condition it can be matched with commonly used UV curing equipment. Most preferably, the liquid photoinitiator is selected from photoinitiator 1173.
[0009] The residue-free UV-curable peelable adhesive described above further includes a solid initiator as the photoinitiator. The weight ratio of the liquid initiator to the solid initiator is 1:1 to 5:1. Under these conditions, both complete dissolution of the initiator and sufficient curing of the peelable adhesive are ensured. Most preferably, the weight ratio of the liquid initiator to the solid initiator is 1:1.
[0010] The residue-free UV-curable peelable adhesive described above uses a solid photoinitiator selected from any one or a mixture of several of the following: 1-hydroxycyclohexylphenyl ketone (i.e., photoinitiator 184), 2,4,6-trimethylbenzoyl diphenylphosphine oxide (i.e., solid photoinitiator TPO), bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide (i.e., solid photoinitiator 819), and 2-methyl-1-(4-methylthiophenyl)-2-morpholino-1-propanone (i.e., solid photoinitiator 907). Preferably, the solid photoinitiator is selected from any one of solid photoinitiator TPO, solid photoinitiator 819, and solid photoinitiator 907. Under these conditions, a wider range of UV absorption wavelengths can be covered, achieving more complete curing. Most preferably, the solid photoinitiator is selected from solid photoinitiator TPO.
[0011] The residue-free UV-curable peelable adhesive described above uses a polyurethane-modified acrylate resin selected from any one or a mixture of two or more of UV3000, UV3000C, UV3003, SD860, SD1099, SD6233, and SD7538. Preferably, the polyurethane-modified acrylate resin is selected from UV3000 or SD6233. Most preferably, the polyurethane-modified acrylate resin is selected from UV3000.
[0012] The residue-free UV-curable peelable adhesive described above further includes 1-8 parts of a thixotropic agent, wherein the thixotropic agent is selected from any one of fumed silica, organobentonite, and polyamide wax. Preferably, the thixotropic agent is selected from fumed silica. Most preferably, the thixotropic agent is selected from fumed silica JY-R974.
[0013] The residue-free UV-curable peelable adhesive described above also includes 0.01-1.0 parts of color powder, wherein the color powder is selected from any one of inorganic pigments, organic pigments, and dyes.
[0014] Based on the same inventive concept, this invention provides a method for preparing a residue-free UV-curable peelable adhesive, comprising the following steps: Add the dissolved photoinitiator to the polyurethane-modified acrylate resin according to the set ratio, stir at 80-90℃ for 30-50 minutes, and then degas under vacuum to obtain UV-curable peelable adhesive.
[0015] Based on the same inventive concept, this invention provides the application of a residue-free UV-curable peelable adhesive as described above, or a residue-free UV-curable peelable adhesive prepared by the preparation method described above. The residue-free UV-curable peelable adhesive is used in fields such as temporary protection of printed circuit boards, temporary fixation of electronic components, CVD coating masking, PVD coating masking, electroplating masking, anodizing masking, battery pack insulation, or temporary protection of displays and touch modules.
[0016] Compared with existing technologies, the effects and advantages of this invention are: This invention provides a residue-free UV-curable peelable adhesive that directly solves the problem of substrate contamination caused by small molecule monomers and additives, thereby achieving excellent results with no residue. At the same time, by reasonably selecting the viscosity range of the resin (viscosity at room temperature 3000-150000 mPa.s), good adhesive process operability can be achieved. In addition, the peelable adhesive also has good flexibility. Detailed Implementation
[0017] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0018] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. The term "and / or" as used in this specification includes any and all combinations of one or more of the associated listed items.
[0019] Unless otherwise specified, the experimental methods used in the following examples are conventional methods.
[0020] Unless otherwise specified, all materials and reagents used in the following examples are commercially available.
[0021] Polyurethane modified acrylate resin: UV3000 was purchased from Zhongshan Qianyou Chemical Materials Co., Ltd. SD6233, SD1110, and SD7560 were purchased from Guangzhou Songda New Materials Technology Co., Ltd. Liquid photoinitiator 1173, liquid photoinitiator TPO-L, solid photoinitiator TPO, solid photoinitiator 819, and solid photoinitiator 907 were all purchased from German company, Röhne Chemicals GmbH. Fumed silica was purchased from Guangzhou Jibisheng Technology Industry Co., Ltd. as JY-R974. The blue pigment was purchased from BASF's D7079.
[0022] Example 1 This embodiment provides a residue-free UV-curable peelable adhesive, mainly prepared from the following raw materials in parts by weight: 93.9 parts of polyurethane-modified acrylate resin, 6 parts of photoinitiator, and 0.1 parts of colorant; wherein, the polyurethane-modified acrylate resin is selected from UV3000, with a viscosity of 110000 mPa·s at room temperature; the photoinitiator is a mixture of liquid photoinitiator 1173 and solid photoinitiator TPO, wherein the weight ratio of liquid photoinitiator 1173 to solid photoinitiator TPO is 1:1; and the colorant is D7079.
[0023] This embodiment provides a method for preparing a residue-free UV-curable peelable adhesive, comprising the following steps: Add solid photoinitiator TPO to liquid photoinitiator 1173 according to the set ratio, and stir at room temperature until completely dissolved; add the dissolved mixed photoinitiator and color powder D7079 to polyurethane modified acrylate resin UV3000 according to the set ratio, stir at 80℃ for 30 minutes, and then degas under vacuum to obtain UV-curable peelable adhesive.
[0024] Example 2: This embodiment provides a residue-free UV-curable peelable adhesive, mainly prepared from the following raw materials in parts by weight: 90.5 parts of polyurethane-modified acrylate resin, 5 parts of photoinitiator, 4 parts of thixotropic agent, and 0.5 parts of colorant; wherein, the polyurethane-modified acrylate resin is selected from SD6233, with a viscosity of 5000 mPa·s at room temperature; the photoinitiator is a mixture of liquid photoinitiator 1173 and solid photoinitiator TPO, wherein the weight ratio of liquid photoinitiator 1173 to solid photoinitiator TPO is 3:1; the thixotropic agent is fumed silica JY-R974; and the colorant is D7079.
[0025] This embodiment provides a method for preparing a residue-free UV-curable peelable adhesive, comprising the following steps: Solid photoinitiator TPO was added to liquid photoinitiator 1173 according to the set ratio and stirred at room temperature until completely dissolved. The dissolved mixed photoinitiator, thixotropic agent JY-R974, and colorant D7079 were added to polyurethane modified acrylate resin SD6233 according to the set ratio and stirred at 80℃ for 30 minutes. Then, vacuum degassing was performed to obtain UV-curable peelable adhesive.
[0026] Example 3: This embodiment provides a residue-free UV-curable peelable adhesive, mainly prepared from the following raw materials in parts by weight: 93.9 parts of polyurethane-modified acrylate resin, 6 parts of photoinitiator, and 0.1 parts of colorant; wherein, the polyurethane-modified acrylate resin is selected from UV3000, with a viscosity of 110000 mPa·s at room temperature; the photoinitiator is liquid photoinitiator 1173; and the colorant is D7079.
[0027] This embodiment provides a method for preparing a residue-free UV-curable peelable adhesive, comprising the following steps: Liquid photoinitiator 1173 and colorant D7079 were added to polyurethane modified acrylate resin UV3000 according to the set ratio. The mixture was stirred at 80°C for 30 minutes and then degassed under vacuum to obtain UV-curable peelable adhesive.
[0028] Example 4: This embodiment provides a residue-free UV-curable peelable adhesive, mainly prepared from the following raw materials in parts by weight: 93 parts of polyurethane-modified acrylate resin, 6 parts of photoinitiator, and 1 part of colorant; wherein, the polyurethane-modified acrylate resin is selected from UV3000, with a viscosity of 110000 mPa·s at room temperature; the photoinitiator is a mixture of liquid photoinitiator 1173 and solid photoinitiator 819, with a weight ratio of 1:1; and the colorant is D7079.
[0029] This embodiment provides a method for preparing a residue-free UV-curable peelable adhesive, comprising the following steps: Solid photoinitiator 819 was added to liquid photoinitiator 1173 according to the set ratio and stirred at room temperature until completely dissolved. The dissolved mixed photoinitiator and color powder D7079 were added to polyurethane modified acrylate resin UV3000 according to the set ratio and stirred at 80°C for 30 minutes. Then, vacuum degassing was performed to obtain UV-curable peelable adhesive.
[0030] Example 5: This embodiment provides a residue-free UV-curable peelable adhesive, mainly prepared from the following raw materials in parts by weight: 93.99 parts of polyurethane-modified acrylate resin, 6 parts of photoinitiator, and 0.01 parts of colorant; wherein, the polyurethane-modified acrylate resin is selected from UV3000, with a viscosity of 110000 mPa·s at room temperature; the photoinitiator is a mixture of liquid photoinitiator TPO-L and solid photoinitiator 907, with a weight ratio of liquid photoinitiator TPO-L to solid photoinitiator TPO of 5:1; and the colorant is D7079.
[0031] This embodiment provides a method for preparing a residue-free UV-curable peelable adhesive, comprising the following steps: Add solid photoinitiator 907 to liquid photoinitiator TPO-L according to the set ratio, and stir at room temperature until completely dissolved; add the dissolved mixed photoinitiator and color powder D7079 to polyurethane modified acrylate resin UV3000 according to the set ratio, stir at 80℃ for 30 minutes, and then degas under vacuum to obtain UV-curable peelable adhesive.
[0032] Comparative Example 1: The difference from Example 1 is that the polyurethane modified acrylate resin is selected from SD1110, with a viscosity of 2500 mP.s at room temperature.
[0033] Comparative Example 2: The difference from Example 1 is that the polyurethane modified acrylate resin is selected from SD7560, with a viscosity of 160,000 mPa·s at room temperature.
[0034] Comparative Example 3: The difference from Example 1 is that the photoinitiator is only the solid photoinitiator TPO.
[0035] The comparative example provides a method for preparing a UV-curable peelable adhesive, which includes the following steps: Solid photoinitiator TPO and colorant D7079 were added to polyurethane modified acrylate resin UV3000 according to the set ratio. The mixture was stirred at 80°C for 30 minutes and then degassed under vacuum to obtain UV-curable peelable adhesive.
[0036] Test example: 1. Tensile strength and elongation at break of the samples from Examples 1-5 and Comparative Examples 1-3 were tested after curing into films according to GB / T528-2009. Curing conditions: 365nm UV light irradiation for 30s under 300mW / cm light curing conditions.
[0037] 2. The UV peelable adhesives of Examples 1-5 and Comparative Examples 1-3 were tested, and the results are shown in Table 1.
[0038] Table 1. Performance test results of the peelable adhesive in Examples 1-5 and Comparative Examples 1-3
[0039] As shown in Table 1, the tensile strength of the peelable adhesives in Examples 1-5 ranges from 2.8 to 10.2 MPa, exhibiting moderate strength that provides both protection and ease of peeling. Their elongation at break ranges from 240% to 431%, demonstrating good flexibility and ductility. Furthermore, the adhesives all exhibit good handling properties, low peel force, and complete peeling, with no residue at the edges and no marks left in the protected area, indicating a clean and intact peel. In contrast, the data from the peelable adhesives in Comparative Examples 1-3 show that polyurethane-modified acrylate resins with viscosities below 3000 mPa·s exhibit residue problems, while adhesives with viscosities above 150000 mPa·s have poor handling properties and uneven application. Additionally, formulations using only solid photoinitiators are prone to incomplete curing, resulting in poor mechanical properties and a high likelihood of residue problems.
[0040] It should be noted that the specific embodiments are merely representative examples of the present invention, and the technical solution of the present invention is obviously not limited to the above embodiments, and there can be many variations. Those skilled in the art who obtain the present invention based on its explicit disclosure or without objection from the written description should consider it to be within the scope of protection of this patent.
Claims
1. A residue-free UV-curable peelable adhesive, characterized in that, It is mainly prepared from the following raw materials in parts by weight: 90-99 parts of polyurethane modified acrylate resin and 1-8 parts of photoinitiator; wherein, the viscosity of the polyurethane modified acrylate resin at room temperature is 3000-150000 mPa.s.
2. The residue-free UV-curable peelable adhesive according to claim 1, characterized in that, The photoinitiator includes at least one liquid photoinitiator that is in liquid form at room temperature.
3. The residue-free UV-curable peelable adhesive according to claim 2, characterized in that, The liquid photoinitiator is selected from any one or a mixture of several of 2-hydroxy-2-methylphenylacetone, ethyl(2,4,6-trimethylbenzoyl)phenylphosphonate, and bis(2,6-difluoro-3-pyrrolephenyl)bis(2,4,6-trimethylbenzoyl)phosphine oxide.
4. The residue-free UV-curable peelable adhesive according to claim 2, characterized in that, The photoinitiator also includes a solid initiator.
5. The residue-free UV-curable peelable adhesive according to claim 4, characterized in that, The solid photoinitiator is selected from any one or a mixture of several of 1-hydroxycyclohexylphenyl ketone, 2,4,6-trimethylbenzoyl diphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, and 2-methyl-1-(4-methylthiophenyl)-2-morpholino-1-propanone.
6. The residue-free UV-curable peelable adhesive according to claim 1, characterized in that, The polyurethane modified acrylate resin is selected from any one or a mixture of two or more of UV3000, UV3000C, UV3003, SD860, SD1099, SD6233, and SD7538.
7. The residue-free UV-curable peelable adhesive according to claim 1, characterized in that, It also includes 1-8 parts of a thixotropic agent, wherein the thixotropic agent is selected from any one of fumed silica, organobentonite, and polyamide wax.
8. The residue-free UV-curable peelable adhesive according to claim 1, characterized in that, It also includes 0.01-1.0 parts of color powder, which is selected from any one of inorganic pigments, organic pigments, and dyes.
9. The method for preparing the residue-free UV-curable peelable adhesive according to any one of claims 1-8, characterized in that, Includes the following steps: Add the dissolved photoinitiator to the polyurethane-modified acrylate resin according to the set ratio, stir at 80-90℃ for 30-50 minutes, and then degas under vacuum to obtain UV-curable peelable adhesive.
10. An application of the residue-free UV-curable peelable adhesive as described in any one of claims 1-8 or the residue-free UV-curable peelable adhesive prepared by the preparation method as described in claim 9, characterized in that, The residue-free UV-curable peelable adhesive is used for temporary protection of printed circuit boards, temporary fixation of electronic components, CVD coating masking, PVD coating masking, electroplating masking, anodizing masking, battery pack insulation, or temporary protection of displays and touch modules.