Low-stress fast-rebound OCA optical transparent pressure-sensitive adhesive composition and preparation method thereof
By preparing a low-stress fast rebound OCA optical transparent pressure-sensitive adhesive composition containing specific components, the appearance problems after coating and the problems of high stress slow rebound are solved, and excellent performance and reliability are achieved, and suitable for a wide range of optical device applications.
Patent Information
- Application Number
- CN202411860651.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-17
- Publication Date
- 2025-02-28
AI Technical Summary
Existing optical glues are prone to appearance problems such as stripes and patterns after coating and film formation, and high stress and slow rebound limit their performance and reliability in optical device applications.
A low-stress fast rebound OCA optically transparent pressure-sensitive adhesive composition, which includes a prepolymer of polyurethane acrylic resin, a low and high glass transition temperature acrylate monomer, a functional acrylate monomer, a crosslinking agent, a photoinitiator, a thiol chain transfer agent and an anti-aging agent, is prepared by traditional ultraviolet-excited radical copolymerization.
The optical pressure-sensitive adhesive composition is achieved with good compatibility, storage stability and low stress fast rebound, solving the appearance problem after coating film formation, and showing excellent bonding, optical, mechanical and aging reliability in optical device applications.
Smart Images
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Abstract
Description
Technical Field
[0001] The present application relates to the field of adhesives, and in particular to a low-stress fast-rebound OCA optically transparent pressure-sensitive adhesive composition and a preparation method thereof. Background Art
[0002] Optical adhesive is a material used for bonding optical components and plays a key role in many fields, including optical device manufacturing, optical microscopes, communication equipment, and imaging equipment. In order to ensure the performance of these optical devices and systems, materials with excellent optical properties are required. There are many types of optical adhesives on the market, including epoxy resins, acrylates, silicones, and polyurethanes, which often have high transparency, excellent optical properties, and excellent mechanical properties.
[0003] However, these traditional optical adhesives have some problems in certain aspects, which limit their performance and reliability in specific applications. These problems mainly include two aspects: (1) Currently, optical adhesives are often prepared by UV light curing, and the preparation of raw materials relies on foreign imports. Optical adhesives prepared from domestic basic raw materials have defects in formation; (2) Due to the high stress and slow rebound of some optical adhesives, there are certain technical defects in the application end of optical devices, and the product performance cannot meet the application standards. Summary of the invention
[0004] In order to improve the compatibility and storage stability of a pressure-sensitive adhesive, the present application provides a low-stress, fast-rebound OCA optically transparent pressure-sensitive adhesive composition and a preparation method thereof.
[0005] The present application provides a low stress fast rebound OCA optically transparent pressure-sensitive adhesive composition and a preparation method thereof using the following technical solutions: In the first aspect, the present application provides a low stress fast rebound OCA optically transparent pressure-sensitive adhesive composition, which adopts the following technical solution: A low-stress fast-rebound OCA optically transparent pressure-sensitive adhesive composition, which comprises the following components by weight: 40-70 parts of polyurethane acrylic resin prepolymer, 5-35 parts of low glass transition temperature acrylate monomer, 5-35 parts of high glass transition temperature acrylate monomer, 5-35 parts of functional acrylate monomer, 2-10 parts of crosslinking agent, 0.5-2 parts of photoinitiator, 0.5-2 parts of thiol chain transfer agent, and 2-5 parts of antioxidant.
[0006] Preferably, the pressure-sensitive adhesive composition comprises 60 parts of a prepolymer of a polyurethane acrylic resin, 10 parts of a low glass transition temperature acrylate monomer, 15 parts of a high glass transition temperature acrylate monomer, 15 parts of a functional acrylate monomer, 5 parts of a crosslinking agent, 1 part of a photoinitiator, 1 part of a thiol chain transfer agent, and 2 parts of an antioxidant.
[0007] Preferably, the prepolymer of polyurethane acrylic resin is prepared by reacting polyether diol PPG2000, an acrylic monomer containing hydroxyl groups and a polyurethane terminated with a part of isocyanate groups.
[0008] Preferably, the hydroxyl acrylic monomer includes any one of hydroxyethyl acrylate, hydroxypropyl acrylate and hydroxybutyl acrylate.
[0009] Preferably, the high glass transition temperature acrylic acid ester monomer includes any one of isobornyl acrylate and isobornyl methacrylate.
[0010] Preferably, the molecular weight of the polyurethane terminated with some acrylic monomer groups of the hydroxy polyurethane acrylic resin is 6000-10000 g / mol, the molecular weight distribution is less than 2.0, and the transmittance in the visible light range is greater than 85% after adding a photoinitiator to solidify.
[0011] Preferably, the cross-linking agent includes any one of 1,6-hexamethylenediamine bismaleimide and polyethylene glycol (600) or a mixture of both; and the antioxidant includes antioxidant 264.
[0012] Preferably, the photoinitiator is any one of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, photoinitiator 184, and photoinitiator diphenyl-(2,4,6-trimethylbenzoyl)phosphine oxide.
[0013] Preferably, the mercaptan chain transfer agent includes any one of n-dodecyl mercaptan, 1,4-butanediol bis(3-mercaptobutyrate), and pentaerythritol tetrakis(3-secondary mercaptopropionate).
[0014] In a second aspect, the present application provides a method for preparing a low-stress, fast-rebound OCA optically transparent pressure-sensitive adhesive composition, using the following technical solution: A method for preparing a low-stress fast-rebound OCA optically transparent pressure-sensitive adhesive composition comprises the following steps: The prepolymer of polyurethane acrylic resin, low glass transition temperature acrylate monomer, high glass transition temperature acrylate monomer, functional acrylate monomer and crosslinking agent are mixed and stirred, and then a photoinitiator, a thiol chain transfer agent and an antioxidant are added, and stirring is continued to obtain a pressure-sensitive adhesive composition, which is then stored away from light.
[0015] In summary, the present application includes at least one of the following beneficial technical effects: 1. The present application does not require organic solvents to regulate the coating viscosity. The optical pressure-sensitive adhesive composition prepared by the present application can be prepared by traditional ultraviolet light-excited free radical copolymerization, so that the optical pressure-sensitive adhesive composition has good compatibility, storage stability and low-stress fast resilience, which effectively solves the appearance problems such as stripes and patterns that are easy to appear after the existing optical adhesive is coated and formed into a film, as well as the problem of convenient use at the application end of optical devices. It also has excellent bonding properties, optical properties, mechanical properties and aging reliability performance, and is used in a wider range of fields, and has great application prospects in the fields of terminal equipment, foldable terminal equipment, wearable electronic devices, etc. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 This is a stress-strain curve diagram obtained by testing Example 1.
[0017] Figure 2 This is a stress-strain curve diagram obtained from the test of Example 2.
[0018] Figure 3 This is a stress-strain curve diagram obtained from the test of Example 3.
[0019] Figure 4 This is a stress-strain curve diagram obtained from the test of Example 4.
[0020] Figure 5 This is a stress-strain curve diagram obtained from the test of Example 5.
[0021] Figure 6 This is a stress-strain curve diagram obtained from the test of Example 6.
[0022] Figure 7 It is a comparison diagram of stress-strain curves obtained by testing Example 4, Example 5 and Example 6. DETAILED DESCRIPTION
[0023] The present application is further described in detail below with reference to the embodiments: Raw materials description: All raw materials in the examples can be obtained commercially; Example 1 Preparation of low stress fast rebound OCA optically transparent pressure-sensitive adhesive composition: 60 parts of polyurethane acrylic resin prepolymer, 10 parts of low glass transition temperature acrylate monomer, 15 parts of high glass transition temperature acrylate monomer, and 15 parts of functional acrylate monomer were mixed in a stirring tank, and stirred at a speed of 500 rpm for 30 minutes. Subsequently, 1 part of photoinitiator, 1.5 parts of thiol chain transfer agent and 2 parts of antioxidant were added to the stirring tank, and slowly stirred at a speed of 300 rpm for 30 minutes to obtain a low stress fast rebound OCA optically transparent pressure-sensitive adhesive composition, which was stored away from light.
[0024] Among them, the low glass transition temperature acrylate monomer is isooctyl acrylate, the high glass transition temperature acrylate monomer is isobornyl acrylate, the functional acrylate monomer is hydroxyethyl acrylate, the photoinitiator is 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, the thiol chain transfer agent is pentaerythritol tetrakis (3-secondary mercaptopropionate), and the antioxidant is antioxidant 264.
[0025] The pressure-sensitive adhesive composition prepared above was coated on a PET release film with a surface treated with silicone oil, and cured using a 365nm LED ultraviolet light source for 2 minutes. After curing, an adhesive film was obtained, and stress and strain were tested. The test results are as follows: Figure 1 shown.
[0026] Example 2 Preparation of low stress fast rebound OCA optically transparent pressure-sensitive adhesive composition: 60 parts of polyurethane acrylic resin prepolymer, 10 parts of low glass transition temperature acrylate monomer, 15 parts of high glass transition temperature acrylate monomer, 15 parts of functional acrylate monomer and 5 parts of cross-linking agent were mixed in a stirring tank, and stirred at a speed of 500 rpm for 30 minutes. Subsequently, 1 part of photoinitiator, 1.5 parts of thiol chain transfer agent and 2 parts of antioxidant were added to the stirring tank, and slowly stirred at a speed of 300 rpm for 30 minutes to obtain a low stress fast rebound OCA optically transparent pressure-sensitive adhesive composition, which was stored away from light.
[0027] Among them, the low glass transition temperature acrylate monomer is isooctyl acrylate, the high glass transition temperature acrylate monomer is isobornyl acrylate, the functional acrylate monomer is hydroxyethyl acrylate, the photoinitiator is 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, the cross-linking agent is 1,6-hexanediamine bismaleimide, the thiol chain transfer agent is pentaerythritol tetrakis (3-secondary mercaptopropionate), and the antioxidant is antioxidant 264.
[0028] The pressure-sensitive adhesive composition prepared above was coated on a PET release film with a surface treated with silicone oil, and cured using a 365nm LED ultraviolet light source for 2 minutes. After curing, an adhesive film was obtained, and stress and strain were tested. The test results are as follows: Figure 2 shown.
[0029] Example 3 Preparation of low stress fast rebound OCA optically transparent pressure-sensitive adhesive composition: 60 parts of polyurethane acrylic resin prepolymer, 10 parts of low glass transition temperature acrylate monomer, 15 parts of high glass transition temperature acrylate monomer, 15 parts of functional acrylate monomer and 5 parts of cross-linking agent were mixed in a stirring tank, and stirred at a speed of 500 rpm for 30 minutes. Subsequently, 1 part of photoinitiator, 1.5 parts of thiol chain transfer agent and 2 parts of antioxidant were added to the stirring tank, and slowly stirred at a speed of 300 rpm for 30 minutes to obtain a low stress fast rebound OCA optically transparent pressure-sensitive adhesive composition, which was stored away from light.
[0030] Among them, the low glass transition temperature acrylate monomer is isooctyl acrylate, the high glass transition temperature acrylate monomer is isobornyl acrylate, the functional acrylate monomer is hydroxyethyl acrylate, the photoinitiator is 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, the cross-linking agent is polyethylene glycol (600), the thiol chain transfer agent is pentaerythritol tetrakis (3-secondary mercaptopropionate), and the antioxidant is antioxidant 264.
[0031] The pressure-sensitive adhesive composition prepared above was coated on a PET release film with a surface treated with silicone oil, and cured using a 365nm LED ultraviolet light source for 2 minutes. After curing, an adhesive film was obtained, and stress and strain were tested. The test results are as follows: Figure 3 shown.
[0032] Example 4 Preparation of low stress fast rebound OCA optically transparent pressure-sensitive adhesive composition: 60 parts of polyurethane acrylic resin prepolymer, 10 parts of low glass transition temperature acrylate monomer, 15 parts of high glass transition temperature acrylate monomer, 15 parts of functional acrylate monomer and 5 parts of cross-linking agent were mixed in a stirring tank, and stirred at a speed of 500 rpm for 30 minutes. Subsequently, 1 part of photoinitiator, 1.5 parts of thiol chain transfer agent and 2 parts of antioxidant were added to the stirring tank, and slowly stirred at a speed of 300 rpm for 30 minutes to obtain a low stress fast rebound OCA optically transparent pressure-sensitive adhesive composition, which was stored away from light.
[0033] Among them, the low glass transition temperature acrylate monomer is isooctyl acrylate, the high glass transition temperature acrylate monomer is isobornyl acrylate, the functional acrylate monomer is hydroxyethyl acrylate, the photoinitiator is 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, the cross-linking agent is a mixture of 1 part of 1,6-hexanediamine bismaleimide and 4 parts of polyethylene glycol (600), the thiol chain transfer agent is pentaerythritol tetrakis (3-secondary mercaptopropionate), and the antioxidant is antioxidant 264.
[0034] The pressure-sensitive adhesive composition prepared above was coated on a PET release film with a surface treated with silicone oil, and cured using a 365nm LED ultraviolet light source for 2 minutes. After curing, an adhesive film was obtained, and stress and strain were tested. The test results are as follows: Figure 4 shown.
[0035] Example 5 Preparation of low stress fast rebound OCA optically transparent pressure-sensitive adhesive composition: 60 parts of polyurethane acrylic resin prepolymer, 10 parts of low glass transition temperature acrylate monomer, 15 parts of high glass transition temperature acrylate monomer, 10 parts of functional acrylate monomer and 5 parts of cross-linking agent were mixed in a stirring tank, and stirred at a speed of 500 rpm for 30 minutes. Subsequently, 1 part of photoinitiator, 1.5 parts of thiol chain transfer agent and 2 parts of antioxidant were added to the stirring tank, and slowly stirred at a speed of 300 rpm for 30 minutes to obtain a low stress fast rebound OCA optically transparent pressure-sensitive adhesive composition, which was stored away from light.
[0036] Among them, the low glass transition temperature acrylate monomer is isooctyl acrylate, the high glass transition temperature acrylate monomer is isobornyl acrylate, the functional acrylate monomer is hydroxyethyl acrylate, the photoinitiator is 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, the cross-linking agent is a mixture of 2 parts of 1,6-hexanediamine bismaleimide and 3 parts of polyethylene glycol (600), the thiol chain transfer agent is pentaerythritol tetrakis (3-secondary mercaptopropionate), and the antioxidant is antioxidant 264.
[0037] The pressure-sensitive adhesive composition prepared above was coated on a PET release film with a surface treated with silicone oil, and cured using a 365nm LED ultraviolet light source for 2 minutes. After curing, an adhesive film was obtained, and stress and strain were tested. The test results are as follows: Figure 5 shown.
[0038] Example 6 Preparation of low stress fast rebound OCA optically transparent pressure-sensitive adhesive composition: 60 parts of polyurethane acrylic resin prepolymer, 10 parts of low glass transition temperature acrylate monomer, 15 parts of high glass transition temperature acrylate monomer, 10 parts of functional acrylate monomer and 5 parts of cross-linking agent were mixed in a stirring tank, and stirred at a speed of 500 rpm for 30 minutes. Subsequently, 1 part of photoinitiator, 1.5 parts of thiol chain transfer agent and 2 parts of antioxidant were added to the stirring tank, and slowly stirred at a speed of 300 rpm for 30 minutes to obtain a low stress fast rebound OCA optically transparent pressure-sensitive adhesive composition, which was stored away from light.
[0039] Among them, the low glass transition temperature acrylate monomer is isooctyl acrylate, the high glass transition temperature acrylate monomer is isobornyl acrylate, the functional acrylate monomer is hydroxyethyl acrylate, the photoinitiator is 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, the cross-linking agent is a mixture of 3 parts of 1,6-hexanediamine bismaleimide and 2 parts of polyethylene glycol (600), the thiol chain transfer agent is pentaerythritol tetrakis (3-secondary mercaptopropionate), and the antioxidant is antioxidant 264.
[0040] The pressure-sensitive adhesive composition prepared above was coated on a PET release film with a surface treated with silicone oil, and cured using a 365nm LED ultraviolet light source for 2 minutes. After curing, an adhesive film was obtained, and stress and strain were tested. The test results are as follows: Figure 6 shown.
[0041] Performance testing The samples prepared in Examples 1-6 were sampled and subjected to the following performance tests: (1) Peel strength test The glass strength of the samples in the examples was tested according to GB / T 2792-2014, and the test results are entered in Table 1.
[0042] (2) Haze performance test Taking GB / T 2410-2008 as the testing standard, the haze of the samples in the examples was tested using a light transmittance haze meter, and the test results were filled in Table 1.
[0043] Table 1 Performance test results of samples of Examples 1-6 Test items Peel strength / (gf / in) Haze Example 1 5001 0.23 Example 2 3030 0.26 Example 3 3845 0.20 Example 4 4168 0.28 Example 5 3886 0.19 Example 6 3740 0.24 Combined with Figure 1-2 It can be seen that after adding the cross-linking agent 1,6-hexamethylenediamine bismaleimide, the stress increases and the strain decreases.
[0044] Combined with Figure 1 and Figure 3 It can be seen that after adding the cross-linking agent polyethylene glycol (600), the stress decreases and the strain increases.
[0045] Combination Figures 4 to 7 It can be seen that after 1,6-hexamethylenediamine bismaleimide and polyethylene glycol (600) are combined as cross-linking agents and added into the system, the stress decreases and the strain increases, and Example 5 is the optimal method of combining the two, which has the performance of low stress and fast rebound.
[0046] In summary, compared with the prior art, the present invention does not require organic solvents to regulate the coating viscosity during the preparation process, and the optical pressure-sensitive adhesive composition prepared by the present invention can be prepared by traditional ultraviolet light-excited free radical tools, so that the optical pressure-sensitive adhesive composition prepared by the present invention has good compatibility, storage stability and low stress fast resilience, effectively solving the appearance problems such as stripes and patterns that are easy to appear after the existing optical adhesive is coated and formed into a film, as well as the problem of convenient use at the application end of optical devices, and also has excellent bonding performance, optical performance, mechanical performance and aging reliability performance, and the field of use is more extensive. It has great prospects in the fields of terminal equipment, foldable terminal equipment, wearable electronic devices, etc.
[0047] This specific embodiment is only an explanation of the present application, and it is not a limitation of the present application. Through the above description, relevant staff can make various changes and modifications without deviating from the technical idea of the present application. The technical scope of the present application is not limited to the content in the specification, and its technical scope must be determined according to the scope of the claims.
Claims
1. A low stress fast rebound OCA optically transparent pressure-sensitive adhesive composition, characterized in that: The pressure-sensitive adhesive composition comprises the following components by weight: 40-70 parts of polyurethane acrylic resin prepolymer, 5-35 parts of low glass transition temperature acrylate monomer, 5-35 parts of high glass transition temperature acrylate monomer, 5-35 parts of functional acrylate monomer, 2-10 parts of crosslinking agent, 0.5-2 parts of photoinitiator, 0.5-2 parts of thiol chain transfer agent, and 2-5 parts of antioxidant.
2. The low stress fast rebound OCA optically transparent pressure-sensitive adhesive composition according to claim 1, characterized in that: The pressure-sensitive adhesive composition comprises 60 parts of a prepolymer of a polyurethane acrylic resin, 10 parts of a low glass transition temperature acrylate monomer, 15 parts of a high glass transition temperature acrylate monomer, 15 parts of a functional acrylate monomer, 5 parts of a crosslinking agent, 1 part of a photoinitiator, 1 part of a thiol chain transfer agent, and 2 parts of an antioxidant.
3. The low stress fast rebound OCA optically transparent pressure-sensitive adhesive composition according to claim 1, characterized in that: The prepolymer of the polyurethane acrylic resin is prepared by reacting a polyether diol PPG2000, an acrylic monomer containing a hydroxyl group and a polyurethane terminated with a portion of isocyanate groups.
4. The low stress fast rebound OCA optically transparent pressure-sensitive adhesive composition according to claim 1, characterized in that: The hydroxyl acrylic monomer includes any one of hydroxyethyl acrylate, hydroxypropyl acrylate and hydroxybutyl acrylate.
5. The low stress fast rebound OCA optically transparent pressure-sensitive adhesive composition according to claim 1, characterized in that: The high glass transition temperature acrylic acid ester monomer includes any one of isobornyl acrylate and isobornyl methacrylate.
6. The low stress fast rebound OCA optically transparent pressure-sensitive adhesive composition according to claim 1, characterized in that: The molecular weight of the polyurethane terminated with some acrylic monomer groups of the hydroxy polyurethane acrylic resin is 6000-10000 g / mol, the molecular weight distribution is less than 2.0, and the transmittance in the visible light range is greater than 85% after adding a photoinitiator to solidify.
7. The low stress fast rebound OCA optically transparent pressure-sensitive adhesive composition according to claim 1, characterized in that: The cross-linking agent includes any one of 1,6-hexamethylenediamine bismaleimide and polyethylene glycol (600) or a mixture of the two; the antioxidant includes antioxidant 264.
8. The low stress fast rebound OCA optically transparent pressure-sensitive adhesive composition according to claim 1, characterized in that: The photoinitiator is any one of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, photoinitiator 184, and photoinitiator diphenyl-(2,4,6-trimethylbenzoyl)phosphine oxide.
9. The low stress fast rebound OCA optically transparent pressure-sensitive adhesive composition according to claim 1, characterized in that: The mercaptan chain transfer agent includes any one of n-dodecyl mercaptan, 1,4-butanediol bis(3-mercaptobutyrate), and pentaerythritol tetrakis(3-secondary mercaptopropionate).
10. A method for preparing the low stress fast rebound OCA optically transparent pressure-sensitive adhesive composition according to any one of claims 1 to 9, characterized in that: The steps include: The prepolymer of polyurethane acrylic resin, low glass transition temperature acrylate monomer, high glass transition temperature acrylate monomer, functional acrylate monomer and crosslinking agent are mixed and stirred, and then a photoinitiator, a thiol chain transfer agent and an antioxidant are added, and stirring is continued to obtain a pressure-sensitive adhesive composition, which is then stored away from light.