Two-component acrylate adhesive for optical components and method for its production

Abstract

The application discloses a two-component acrylate adhesive, a preparation method and application thereof. The two-component acrylate adhesive comprises: component A, which comprises an acrylate polymer (a) dispersed in a solvent; and component B, which comprises a partially blocked isocyanate curing agent (b), which is a reactant of an isocyanate trimer and a ketoxime, wherein the blocking ratio of isocyanate groups is 35% to 65%; wherein the acrylate copolymer (a) is a copolymer comprising units derived from a (meth) acrylic acid monomer, units derived from a (meth) acrylic aryl ester monomer, units derived from a (meth) acrylic acid ester monomer containing a hydroxyl group, units derived from a (meth) acrylic alkyl ester monomer and units derived from a free radical polymerizable hindered amine light stabilizer. The two-component acrylate adhesive can significantly improve the high-temperature yellowing resistance, secondary construction performance and stability under high-temperature and high-humidity environments.

Description

Technical Field

[0001] This invention belongs to the field of solvent-based acrylate adhesive preparation, and particularly relates to a two-component acrylate adhesive for optical components and its preparation method. Background Technology

[0002] In recent years, the market demand for LCD panels and touch screens has increased significantly, driving the development and innovation of electronic optical components technology in the field of image display. Polarizing films, one of the core components, are bonded using adhesives. This method meets the performance requirements of electronic optical components, demanding thinness, high density, and durability. Acrylic adhesives for optical components are crucial raw materials in the manufacturing and use of electronic optical components, playing an irreplaceable role in the performance release and stable operation of these components.

[0003] Polarizing films, a component of electronic optical components, require specific performance advantages under special operating conditions. Their reliability deteriorates when exposed to heat, and prolonged high-temperature operation can cause ordinary adhesives to yellow due to resin discoloration, affecting the film's performance. Furthermore, during the coating process, secondary application and recoating are often necessary. Conventional adhesives, having already undergone two-component activation and cross-linking, exhibit internal cross-linking, making proper adhesion to the substrate impossible during secondary application, rendering the film unusable. High-temperature and high-humidity environments, particularly large-size, high-definition LCD panels and demanding operating conditions, exacerbate the problems of reduced polarizing film reliability and shrinkage / deformation in high-humidity environments. To meet the performance requirements of emerging industries for electronic optical components, acrylic adhesives for optical components, a key factor influencing their performance and quality, require technological innovation and breakthroughs.

[0004] This invention provides a two-component acrylate adhesive composition for optical components and its preparation method. A hindered amine light stabilizer containing double-bonded groups is grafted onto the acrylate polymer molecular chain via polymerization, forming a permanently light-stabilized polymer with hindered amine functional groups. This light stabilizer effectively avoids loss due to physical migration or volatilization, improving and enhancing the dispersion performance and light stabilization effect of the hindered amine light stabilizer in the polymer, allowing the film to maintain excellent light stability in subsequent long-term high-temperature working environments. Simultaneously, a partial end-capping curing agent is used in combination with the acrylate adhesive, employing a two-step curing process. In the first curing step, the hydroxyl groups in the linear polymer acrylate resin react with the exposed isocyanate to produce a large-molecule linear adhesive. During application, the coating is peeled off and cut, and the film retains a certain strength, allowing for complete peeling. After application, a further high-temperature curing process is performed, during which the blocked isocyanate is unblocked, continuing micro-crosslinking, further improving the film strength and enhancing reliability under high-temperature and high-humidity conditions. The problem of shrinkage and deformation in high-humidity environments is solved, resulting in a significant improvement in high-temperature and high-humidity resistance. Summary of the Invention

[0005] The purpose of this invention is to provide a two-component acrylate adhesive for optical components and its preparation method. This two-component acrylate adhesive can be used for bonding optical components and can significantly improve the high-temperature yellowing resistance, secondary construction performance, and stability of electronic optical components under high temperature and high humidity environments without affecting the mechanical properties of the optical components.

[0006] According to the method for preparing a two-component acrylate adhesive for optical components described in this invention, a hindered amine light stabilizer containing double bond groups is grafted onto the acrylate polymer molecular chain through a polymerization reaction to form a permanently light-stabilized polymer with hindered amine functional groups. This light stabilizer effectively avoids loss due to physical migration or volatilization, improves and enhances the dispersion performance and light stabilization effect of the hindered amine light stabilizer in the polymer, allowing the film to maintain excellent light stability in subsequent long-term high-temperature working environments. Simultaneously, a partial end-capping curing agent is used in combination with the acrylate adhesive, employing a two-step curing process. In the first curing step, the hydroxyl groups in the linear polymeric acrylic resin react with the exposed isocyanate to produce a large-molecule linear adhesive. During the coating process, the film can be peeled off and cut again, maintaining a certain strength and allowing for complete peeling. After application, a further high-temperature curing process is performed, during which the blocked isocyanate is unblocked, continuing micro-crosslinking. This further enhances the film strength and improves reliability under high-temperature and high-humidity conditions, resolving the problem of shrinkage and deformation in high-humidity environments. The high-temperature and high-humidity resistance is thus significantly improved.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0008] According to a first aspect of the present invention, a two-component acrylic adhesive is provided, comprising component A and component B, wherein,

[0009] Component A contains an acrylate polymer (a) dispersed in a solvent.

[0010] Component B contains a partially blocked isocyanate curing agent (b), wherein,

[0011] The acrylate copolymer (a) is a copolymer comprising units derived from (meth)acrylic acid monomers, units derived from (meth)acrylic acid aryl ester monomers, units derived from (meth)acrylic acid ester monomers containing hydroxyl groups, units derived from (meth)acrylic acid alkyl ester monomers, and units derived from hindered amine light stabilizers that can be polymerized by free radicals.

[0012] The partially blocked isocyanate curing agent (b) is a reaction product of isocyanate trimer and ketoxime, and the isocyanate group blocking ratio is 35% to 65%, preferably 40% to 60%.

[0013] Preferably, the content of acrylate polymer (a) is 90-95 parts by weight, and the content of partially blocked isocyanate curing agent (b) is 5-10 parts by weight.

[0014] Preferably, the weight-average molecular weight of the acrylate polymer (a) is 1 million to 3 million, more preferably 1 million to 2 million.

[0015] Preferably, the solid content of component A is 10wt% to 30wt%, more preferably 15wt% to 25wt%.

[0016] It should be noted that the weight-average molecular weight in this invention refers to the weight-average molecular weight (Mw) of the polymer as determined by gel permeation chromatography (GPC).

[0017] Preferably, the aryl ester monomer of (meth)acrylate is (meth)acrylate C6-C6. 12 Aryl esters, more preferably selected from one or more of benzyl (meth)acrylate, phenyl (meth)acrylate, and phenoxyethyl (meth)acrylate.

[0018] Preferably, the hydroxyl-containing (meth)acrylate monomer is a hydroxyl C1-C6 alkyl methacrylate, more preferably one or more selected from 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 3-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate and 6-hydroxyhexyl methacrylate.

[0019] Preferably, the alkyl methacrylate is (meth)acrylic acid C1-C2. 12 Alkyl esters, more preferably selected from one or more of methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, tert-butyl methacrylate, pentyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, n-octyl methacrylate, isooctyl methacrylate, n-nonyl methacrylate, isononyl methacrylate, n-decyl methacrylate, isodecyl methacrylate, undecyl methacrylate, and lauryl methacrylate.

[0020] Preferably, the hindered amine light stabilizer structure that can be polymerized by free radicals is as follows:

[0021]

[0022] Preferably, the amount of the free radical polymerizable hindered amine light stabilizer is 0.01 wt% to 0.5 wt%, more preferably 0.1 wt% to 0.2 wt%, relative to the total weight of 100 wt% of the monomer.

[0023] Preferably, in the preparation of the acrylate polymer (a), the amount of the (meth)acrylate monomer is 1 wt% to 3 wt% relative to the total weight of 100 wt% of the monomers used in the preparation of component A, the amount of the (meth)acrylate aryl acrylate monomer is 3 wt% to 40 wt%, the amount of the hydroxyl-containing (meth)acrylate monomer is 3 wt% to 5 wt%, and the amount of the (meth)acrylate alkyl ester is 60 wt% to 70 wt%.

[0024] Preferably, the weight ratio of isocyanate trimer to ketoxime is 1 to 10:1, more preferably 3.5 to 5:1.

[0025] Preferably, the ketoxime is one or more of methyl ethyl ketone oxime, butanone oxime, acetone oxime, formaldehyde oxime, acetaldehyde oxime, and cyclohexanone oxime, more preferably methyl ethyl ketone oxime.

[0026] Preferably, the isocyanate trimer is an HDI trimer.

[0027] Preferably, the solvent in component A is selected from one or more of aromatic hydrocarbon solvents, aliphatic hydrocarbon solvents, alicyclic hydrocarbon solvents, ether solvents, halogenated hydrocarbon solvents, ester solvents, ketone solvents, and nitrile solvents.

[0028] Preferably, the aromatic hydrocarbon solvent is selected from any one or more of benzene, toluene, and xylene.

[0029] Preferably, the aliphatic hydrocarbon solvent is selected from any one or more of n-pentane, n-hexane, n-heptane, and n-octane.

[0030] Preferably, the alicyclic hydrocarbon solvent is one or more selected from cyclopentane, cyclohexane, cycloheptane, and cyclooctane.

[0031] Preferably, the ether solvent is selected from any one or more of diethyl ether, diisopropyl ether, dibutyl ether, tetrahydrofuran, anisole, phenethyl ether, and diphenyl ether.

[0032] Preferably, the halogenated hydrocarbon solvent is selected from any one or more of chloroform, carbon tetrachloride, dichloroethane, and chlorobenzene.

[0033] Preferably, the ester solvent is selected from any one or more of methyl acetate, ethyl acetate, propyl acetate, butyl acetate, and methyl propionate.

[0034] Preferably, the ketone solvent is selected from any one or more of acetone, methyl ethyl ketone, diethyl ketone, methyl isobutyl ketone, and cyclohexanone.

[0035] Preferably, the nitrile solvent is selected from any one or more of acetonitrile and benzonitrile.

[0036] It should be noted that the acrylate polymer (a) and the partially blocked isocyanate curing agent (b) are stored separately. Before application, they should be mixed and then applied.

[0037] According to a second aspect of the present invention, a method for preparing a two-component acrylate adhesive for optical components is provided, comprising the following steps:

[0038] Step 1), Preparation of component A: In the presence of a solvent, acrylic monomer, aryl (meth)acrylate monomer, hydroxyl-containing (meth)acrylate monomer, alkyl (meth)acrylate and hindered amine light stabilizer that can be polymerized on free radicals are polymerized in the presence of an initiator to obtain acrylate polymer (a).

[0039] Step 2), Preparation of component B: React the isocyanate trimer and ketoxime to obtain a partially blocked isocyanate curing agent (b).

[0040] Preferably, the polymerization method in step 1) is solution polymerization.

[0041] Preferably, the solvent in step 1) is selected from one or more of aromatic hydrocarbon solvents, aliphatic hydrocarbon solvents, alicyclic hydrocarbon solvents, ether solvents, halogenated hydrocarbon solvents, ester solvents, ketone solvents, and nitrile solvents. The specific types of aromatic hydrocarbon solvents, aliphatic hydrocarbon solvents, alicyclic hydrocarbon solvents, ether solvents, halogenated hydrocarbon solvents, ester solvents, ketone solvents, and nitrile solvents are the same as described above.

[0042] Preferably, the polymerization in step 1) is carried out in the following manner:

[0043] In an inert atmosphere, acrylic monomers, aryl (meth)acrylate monomers, hydroxyl-containing (meth)acrylate monomers, alkyl (meth)acrylates, and hindered amine light stabilizers that can be polymerized on free radicals are added to a solvent. After heating to 60–80°C, an initiator is added, and the polymerization reaction is carried out at a constant temperature.

[0044] Preferably, the amount of initiator is 0.01 wt% to 0.5 wt% relative to 100 wt% of monomer, more preferably 0.05 wt% to 0.2 wt%.

[0045] Preferably, the initiator is a thermal initiator and / or a redox initiator.

[0046] Preferably, the thermal initiator is a persulfate initiator, such as ammonium persulfate, sodium persulfate, potassium persulfate, etc.; or a peroxide initiator, such as hydrogen peroxide, tert-butyl hydrogen peroxide, cumene hydrogen peroxide, diisopropylbenzene hydrogen peroxide, di-tert-butyl hydrogen peroxide, di-tert-pentyl hydrogen peroxide, di(3,3,5-trimethylhexanoyl)peroxide, bis(tert-butylisopropyl)peroxide, benzoyl peroxide, lauroyl peroxide, hexanoyl peroxide, di(4-methylbenzoyl) peroxide, diisopropyl peroxide dicarbonate, di-2-ethylhexyl peroxide dicarbonate, di(4-tert-butylcyclohexyl) peroxide, 2,5-dimethyl-2, 5-Di(tert-butylperoxy)hexane, 1,1-di-tert-butylperoxy-3,3,5-trimethylcyclohexane, 1,1-di-tert-butylperoxycyclohexane, 2,5-dimethyl-2,5-di(2-ethylhexanoic acid peroxy)hexane, tert-butyl peroxypentanoate, tert-butyl peroxybenzoate, tert-butyl peroxyisononanoate, tert-butyl peroxy-2-ethylhexanoate, etc.; azo initiators, such as azobisisobutyronitrile, azobis(cyclohexane-1-formonitrile), azobis(2-cyclopropylpropionitrile), azobis(2-methylbutyronitrile), azobis(2,4-dimethylpentanonitrile), azobis(4-methoxy-2,4-dimethylpentanonitrile), etc.

[0047] The redox initiator comprises one or more oxidants and one or more reductants. Preferably, the oxidant is selected from the thermal initiator, and the reductant is selected from one or more of sodium sulfite, sodium bisulfite, sodium metabisulfite, sodium hydrosulfite, sodium formaldehyde sulfoxylate, and ascorbic acid.

[0048] Preferably, the reaction in step 2) is carried out in the following manner:

[0049] The reaction is carried out by adding ketone to the isocyanate trimer under an inert atmosphere, preferably at a reaction temperature of 40–60 °C.

[0050] According to a third aspect of the invention, the use of a two-component acrylate adhesive for optical components as described in the invention is provided in bonding optical components.

[0051] According to a fourth aspect of the present invention, a method for applying a two-component acrylic adhesive for optical components according to the present invention is provided, comprising the following steps:

[0052] 2-1) Mix component A and component B evenly to obtain an adhesive composition, wherein the content of acrylate polymer (a) in component A is 90-95 parts by weight, and the content of partially blocked isocyanate curing agent (b) in component B is 5-10 parts by weight.

[0053] 2-2) The adhesive composition obtained in step 2-1) is coated to form a uniform coating, and dried at a temperature of 40-70°C to obtain an adhesive film;

[0054] 2-3) Place the adhesive film obtained in step 2-2) between the objects to be adhered and perform high pressure treatment for 20 minutes at 90-110°C and 5-7 atmospheres, and then cure at 90-110°C.

[0055] The application of the two-component acrylic adhesive for optical components of the present invention is not particularly limited and can be applied to any application direction that uses adhesives. Preferably, the two-component acrylic adhesive for optical components can be used for bonding optical components. When the two-component acrylic adhesive for optical components of the present invention is used for bonding optical components, it can significantly improve the high-temperature yellowing resistance, secondary construction performance, and stability under high temperature and high humidity environments of electronic optical components without affecting the mechanical properties of the optical components. Detailed Implementation

[0056] The technical solution of the present invention will be further described below through specific embodiments. The embodiments described in this invention are only for the purpose of helping to understand the present invention and do not specifically limit the scope of the present invention.

[0057] Information on the raw materials involved in specific embodiments of the present invention is shown in Table 1.

[0058] Table 1. Information on Main Raw Materials

[0059]

[0060]

[0061] Unless otherwise specified, raw materials or reagents can be purchased through commercial channels.

[0062] Example 1

[0063] Two-component acrylic adhesives for optical components are prepared according to the following method:

[0064] Preparation of component A: Preparation of acrylate polymer (a)

[0065] In a reaction vessel equipped with a stirrer, reflux condenser, thermometer, and nitrogen tube, add 365g of ethyl acetate solvent, 86.22g of benzyl acrylate, 175g of n-butyl acrylate, 10g of 2-hydroxyethyl acrylate, 5g of acrylic acid, and 0.275g of reactive hindered amine light stabilizer (commercially available, Adico hindered amine light stabilizer LA-82; unless otherwise specified, the same reactive hindered amine light stabilizer is used in other examples). Start stirring, replace the air in the reaction vessel with nitrogen, and after 10 minutes, start heating and adjust the temperature inside the reaction vessel to 65°C. After the temperature inside the reaction vessel stabilizes, add 0.28g of initiator tert-butyl tert-pentanoate to the reaction vessel in one go, and carry out the polymerization reaction at 65°C for 3 hours.

[0066] After the polymerization reaction was completed, the temperature inside the reaction vessel was maintained at 62℃. 331g of ethyl acetate was added to the reaction vessel with stirring, and the mixture was stirred for 10 min. The temperature was then lowered to room temperature to obtain the acrylate polymer (a) dispersed in ethyl acetate solvent. The weight-average molecular weight (Mw) of the polymer, determined by gel permeation chromatography (GPC), was 1.6 million.

[0067] Preparation of component B: Preparation of partially blocked curing agent (b)

[0068] In a reaction vessel equipped with a stirring device, a reflux condenser, a thermometer, and a nitrogen tube, 240g of HT600 (curing agent) was added. Stirring was started, and under nitrogen purging, heating was initiated to adjust the temperature inside the reaction vessel to 50°C. After the temperature inside the reaction vessel stabilized, methyl ethyl ketone oxime was added dropwise. During the dropwise addition, the reaction temperature was maintained below 55°C, and the dropwise addition time was 30 minutes, with a total addition of 60g. The reaction was continuously stirred during the process, and a partially blocked curing agent (b) was finally obtained, in which the isocyanate group blocking ratio was 50%.

[0069] Preparation of adhesive films for performance evaluation

[0070] An acrylate polymer (a) and a partially blocked curing agent (b) dispersed in ethyl acetate solvent were mixed uniformly, with a weight ratio of 9.5:0.5 between the acrylate polymer (a) and the partially blocked curing agent (b). The mixture was then uniformly coated onto a release film using a manual wire-bar coating method. After drying at 60°C for 2 hours, the thickness of the film was controlled to be 30±2 μm. The film was then transferred from the release film to a cellulose acetate resin film. The release film was removed, and a protective release film was placed over the adhesive layer. The cellulose acetate resin film with the adhesive layer was cut into 20cm×30cm pieces, and after removing the release film, it was adhered to a glass plate and pressed. The glass plate with the cellulose acetate resin film was subjected to high-pressure treatment at 100°C and 5 atmospheres for 20 minutes, followed by standing at 100°C / 50%RH for 6 hours to prepare the optical component for performance evaluation.

[0071] Example 2

[0072] Two-component acrylic adhesives for optical components are prepared according to the following method:

[0073] Preparation of component A: Preparation of acrylate polymer (a)

[0074] In a reaction vessel equipped with a stirrer, reflux condenser, thermometer, and nitrogen tube, add 365g of ethyl acetate solvent, 86.22g of benzyl acrylate, 175g of n-butyl acrylate, 10g of 2-hydroxyethyl acrylate, 5g of acrylic acid, and 0.275g of reactive hindered amine light stabilizer. Start stirring and replace the air in the reaction vessel with nitrogen. After 10 minutes, start heating and adjust the temperature inside the reaction vessel to 65°C. After the temperature inside the reaction vessel stabilizes, add 0.5g of tert-butyl tert-pentanoate initiator to the reaction vessel all at once, and carry out the polymerization reaction at 65°C for 3 hours.

[0075] After the polymerization reaction was completed, the temperature inside the reaction vessel was maintained at 62℃. 331g of ethyl acetate was added to the reaction vessel with stirring, and the mixture was stirred for 10 minutes. The temperature was then lowered to room temperature to obtain the acrylate polymer (a) dispersed in ethyl acetate solvent. The weight-average molecular weight (Mw) of the polymer, determined by gel permeation chromatography (GPC), was 1 million.

[0076] Preparation of component B: Preparation of partially blocked curing agent (b)

[0077] In a reaction vessel equipped with a stirring device, a reflux condenser, a thermometer, and a nitrogen tube, 240g of HT600 was added, stirring was started, and heating was initiated under nitrogen purging. The temperature inside the reaction vessel was adjusted to 50°C. After the temperature inside the reaction vessel stabilized, methyl ethyl ketone oxime was added dropwise. During the dropwise addition, the reaction temperature was maintained below 55°C, and the dropwise addition time was 30 minutes, with a total addition of 60g. The reaction was continuously stirred during the process, and a partially blocked curing agent (b) was finally obtained, in which the isocyanate group blocking ratio was 50%.

[0078] Preparation of adhesive films for performance evaluation

[0079] An acrylate polymer (a) and a partially blocked curing agent (b) dispersed in ethyl acetate solvent were mixed uniformly, with a weight ratio of 9.5:0.5 between the acrylate polymer (a) and the partially blocked curing agent (b). The mixture was then uniformly coated onto a release film using a manual wire-bar coating method. After drying at 60°C for 2 hours, the thickness of the film was controlled to be 30±2 μm. The film was then transferred from the release film to a cellulose acetate resin film. The release film was removed, and a protective release film was placed over the adhesive layer. The cellulose acetate resin film with the adhesive layer was cut into 20cm×30cm pieces, and after removing the release film, it was adhered to a glass plate and pressed. The glass plate with the cellulose acetate resin film was subjected to high-pressure treatment at 100°C and 5 atmospheres for 20 minutes, followed by standing at 100°C / 50%RH for 6 hours to prepare the optical component for performance evaluation.

[0080] Example 3

[0081] Two-component acrylic adhesives for optical components are prepared according to the following method:

[0082] Preparation of component A: Preparation of acrylate polymer (a)

[0083] In a reaction vessel equipped with a stirrer, reflux condenser, thermometer, and nitrogen tube, add 365g of ethyl acetate solvent, 86.22g of benzyl acrylate, 175g of n-butyl acrylate, 10g of 2-hydroxyethyl acrylate, 5g of acrylic acid, and 0.275g of reactive hindered amine light stabilizer. Start stirring and replace the air in the reaction vessel with nitrogen. After 10 minutes, start heating and adjust the temperature inside the reaction vessel to 65°C. After the temperature inside the reaction vessel stabilizes, add 0.15g of tert-butyl tert-pentanoate initiator to the reaction vessel in one go, and carry out the polymerization reaction at 65°C for 3 hours.

[0084] After the polymerization reaction was completed, the temperature inside the reaction vessel was maintained at 62°C. 331 g of ethyl acetate was added to the reaction vessel with stirring, and the mixture was stirred for 10 min. The temperature was then lowered to room temperature to obtain the acrylate polymer (a) dispersed in ethyl acetate solvent. The weight-average molecular weight (Mw) of the polymer, determined by gel permeation chromatography (GPC), was 2 million.

[0085] Preparation of component B: Preparation of partially blocked curing agent (b)

[0086] In a reaction vessel equipped with a stirring device, a reflux condenser, a thermometer, and a nitrogen tube, 240g of HT600 was added, stirring was started, and heating was initiated under nitrogen purging. The temperature inside the reaction vessel was adjusted to 50°C. After the temperature inside the reaction vessel stabilized, methyl ethyl ketone oxime was added dropwise. During the dropwise addition, the reaction temperature was maintained below 55°C, and the dropwise addition time was 30 minutes, with a total addition of 60g. The reaction was continuously stirred during the process, and a partially blocked curing agent (b) was finally obtained, in which the isocyanate group blocking ratio was 50%.

[0087] Preparation of adhesive films for performance evaluation

[0088] An acrylate polymer (a) and a partially blocked curing agent (b) dispersed in ethyl acetate solvent were mixed uniformly, with a weight ratio of 9.5:0.5 between the acrylate polymer (a) and the partially blocked curing agent (b). The mixture was then uniformly coated onto a release film using a manual wire-bar coating method. After drying at 60°C for 2 hours, the thickness of the film was controlled to be 30±2 μm. The film was then transferred from the release film to a cellulose acetate resin film. The release film was removed, and a protective release film was placed over the adhesive layer. The cellulose acetate resin film with the adhesive layer was cut into 20cm×30cm pieces, and after removing the release film, it was adhered to a glass plate and pressed. The glass plate with the cellulose acetate resin film was subjected to high-pressure treatment at 100°C and 5 atmospheres for 20 minutes, followed by standing at 100°C / 50%RH for 6 hours to prepare the optical component for performance evaluation.

[0089] Example 4

[0090] Two-component acrylic adhesives for optical components are prepared according to the following method:

[0091] Preparation of component A: Preparation of acrylate polymer (a)

[0092] In a reaction vessel equipped with a stirrer, reflux condenser, thermometer, and nitrogen tube, add 365g of ethyl acetate solvent, 86.22g of benzyl acrylate, 175g of n-butyl acrylate, 10g of 2-hydroxyethyl acrylate, 5g of acrylic acid, and 0.275g of reactive hindered amine light stabilizer. Start stirring and replace the air in the reaction vessel with nitrogen. After 10 minutes, start heating and adjust the temperature inside the reaction vessel to 65°C. After the temperature inside the reaction vessel stabilizes, add 0.28g of tert-butyl tert-pentanoate initiator to the reaction vessel in one go, and carry out the polymerization reaction at 65°C for 3 hours.

[0093] After the polymerization reaction was completed, the temperature inside the reaction vessel was maintained at 62℃. 331g of ethyl acetate was added to the reaction vessel with stirring, and the mixture was stirred for 10 min. The temperature was then lowered to room temperature to obtain the acrylate polymer (a) dispersed in ethyl acetate solvent. The weight-average molecular weight (Mw) of the polymer, determined by gel permeation chromatography (GPC), was 1.6 million.

[0094] Preparation of component B: Preparation of partially blocked curing agent (b)

[0095] In a reaction vessel equipped with a stirring device, a reflux condenser, a thermometer, and a nitrogen tube, 240g of HT600 was added, stirring was started, and heating was started under nitrogen purging. The temperature inside the reaction vessel was adjusted to 50℃. After the temperature inside the reaction vessel stabilized, methyl ethyl ketone oxime was added dropwise. During the dropwise addition, the reaction temperature was maintained below 55℃, and the dropwise addition time was 30 minutes, with a total of 45g added. The reaction was continuously stirred during the process, and finally a partially blocked curing agent (b) was obtained, in which the isocyanate group blocking ratio was 40%.

[0096] Preparation of adhesive films for performance evaluation

[0097] An acrylate polymer (a) and a partially blocked curing agent (b) dispersed in ethyl acetate solvent were mixed uniformly, with a weight ratio of 9.5:0.5 between the acrylate polymer (a) and the partially blocked curing agent (b). The mixture was then uniformly coated onto a release film using a manual wire-bar coating method. After drying at 60°C for 2 hours, the thickness of the film was controlled to be 30±2 μm. The film was then transferred from the release film to a cellulose acetate resin film. The release film was removed, and a protective release film was placed over the adhesive layer. The cellulose acetate resin film with the adhesive layer was cut into 20cm×30cm pieces, and after removing the release film, it was adhered to a glass plate and pressed. The glass plate with the cellulose acetate resin film was subjected to high-pressure treatment at 100°C and 5 atm for 20 minutes, followed by standing at 100°C / 50%RH for 6 hours to prepare the optical component for performance evaluation.

[0098] Example 5

[0099] Two-component acrylic adhesives for optical components are prepared according to the following method:

[0100] Preparation of component A: Preparation of acrylate polymer (a)

[0101] In a reaction vessel equipped with a stirrer, reflux condenser, thermometer, and nitrogen tube, add 365g of ethyl acetate solvent, 86.22g of benzyl acrylate, 175g of n-butyl acrylate, 10g of 2-hydroxyethyl acrylate, 5g of acrylic acid, and 0.275g of reactive hindered amine light stabilizer. Start stirring and replace the air in the reaction vessel with nitrogen. After 10 minutes, start heating and adjust the temperature inside the reaction vessel to 65°C. After the temperature inside the reaction vessel stabilizes, add 0.28g of tert-butyl tert-pentanoate initiator to the reaction vessel in one go, and carry out the polymerization reaction at 65°C for 3 hours.

[0102] After the polymerization reaction was completed, the temperature inside the reaction vessel was maintained at 62℃. 331g of ethyl acetate was added to the reaction vessel with stirring, and the mixture was stirred for 10 min. The temperature was then lowered to room temperature to obtain the acrylate polymer (a) dispersed in ethyl acetate solvent. The weight-average molecular weight (Mw) of the polymer, determined by gel permeation chromatography (GPC), was 1.6 million.

[0103] B. Preparation of partially sealed curing agent (b)

[0104] In a reaction vessel equipped with a stirring device, a reflux condenser, a thermometer, and a nitrogen tube, 240g of HT600 was added, stirring was started, and heating was started under nitrogen purging. The temperature inside the reaction vessel was adjusted to 50℃. After the temperature inside the reaction vessel stabilized, methyl ethyl ketone oxime was added dropwise. During the dropwise addition, the reaction temperature was maintained at no more than 55℃. The dropwise addition time was 30 minutes, and a total of 70g was added. The reaction was continuously stirred during the process, and finally a partially blocked curing agent (b) was obtained, in which the isocyanate group blocking ratio was 60%.

[0105] Preparation of adhesive films for performance evaluation

[0106] An acrylate polymer (a) and a partially blocked curing agent (b) dispersed in ethyl acetate solvent were mixed uniformly, with a weight ratio of 9.5:0.5 between the acrylate polymer (a) and the partially blocked curing agent (b). The mixture was then uniformly coated onto a release film using a manual wire-bar coating method. After drying at 60°C for 2 hours, the thickness of the film was controlled to be 30±2 μm. The film was then transferred from the release film to a cellulose acetate resin film. The release film was removed, and a protective release film was placed over the adhesive layer. The cellulose acetate resin film with the adhesive layer was cut into 20cm×30cm pieces, and after removing the release film, it was adhered to a glass plate and pressed. The glass plate with the cellulose acetate resin film was subjected to high-pressure treatment at 100°C and 5 atmospheres for 20 minutes, followed by standing at 100°C / 50%RH for 6 hours to prepare the optical component for performance evaluation.

[0107] Comparative Example 1

[0108] Except that no reactive hindered amine light stabilizer was added during the preparation of component A, the process was carried out in the same manner as in Example 1.

[0109] More specifically, the two-component adhesive is prepared according to the following method:

[0110] Preparation of component A: Preparation of acrylate polymer

[0111] In a reaction vessel equipped with a stirrer, reflux condenser, thermometer, and nitrogen tube, add 365g of ethyl acetate solvent, 86.22g of benzyl acrylate, 175g of n-butyl acrylate, 10g of 2-hydroxyethyl acrylate, and 5g of acrylic acid. Start stirring and replace the air in the reaction vessel with nitrogen. After 10 minutes, turn on the heater and adjust the temperature inside the reaction vessel to 65°C. After the temperature inside the reaction vessel stabilizes, add 0.28g of tert-butyl tertvalate initiator to the reaction vessel all at once, and carry out the polymerization reaction at 65°C for 3 hours.

[0112] After the polymerization reaction was completed, the temperature inside the reaction vessel was maintained at 62℃. 331g of ethyl acetate was added to the reaction vessel with stirring, and the mixture was stirred for 10 minutes. The temperature was then lowered to room temperature to obtain an acrylate polymer dispersed in ethyl acetate solvent. The weight-average molecular weight (Mw) of the polymer, determined by gel permeation chromatography (GPC), was 1.6 million.

[0113] Preparation of component B: Preparation of partially blocked curing agent

[0114] In a reaction vessel equipped with a stirrer, reflux condenser, thermometer, and nitrogen tube, 240g of HT600 was added, stirring was started, and heating was initiated under nitrogen purging. The temperature inside the reaction vessel was adjusted to 50℃. After the temperature inside the reaction vessel stabilized, methyl ethyl ketone oxime was added dropwise. During the dropwise addition, the reaction temperature was maintained below 55℃, and the dropwise addition time was 30 minutes, with a total addition of 60g. The reaction was continuously stirred during the process, and a partially blocked curing agent was finally obtained, in which the isocyanate group blocking ratio was 50%.

[0115] Preparation of adhesive films for performance evaluation

[0116] An acrylate polymer dispersed in ethyl acetate solvent and a partially blocked curing agent were mixed uniformly, with a weight ratio of 9.5:0.5 between the acrylate polymer and the partially blocked curing agent. The mixture was then uniformly coated onto a release film using a manual wire-bar coating method. After drying at 60°C for 2 hours, the thickness of the film was controlled to be 30±2 μm. The film was then transferred from the release film to a cellulose acetate resin film. The release film was removed, and a protective release film was placed over the adhesive layer. The cellulose acetate resin film with the adhesive layer was cut into 20cm×30cm pieces, and after removing the release film, it was adhered to a glass plate and pressed together. The glass plate with the cellulose acetate resin film was subjected to high-pressure treatment at 100°C and 5 atm for 20 minutes, followed by standing at 100°C / 50%RH for 6 hours to prepare the optical component for performance evaluation.

[0117] Comparative Example 2

[0118] Except for completely blocking the trimer in component B, the procedure was carried out in the same manner as in Example 1.

[0119] More specifically, a two-component acrylate adhesive is prepared according to the following method:

[0120] Preparation of component A: Preparation of acrylate polymer

[0121] In a reaction vessel equipped with a stirrer, reflux condenser, thermometer, and nitrogen tube, add 365g of ethyl acetate solvent, 86.22g of benzyl acrylate, 175g of n-butyl acrylate, 10g of 2-hydroxyethyl acrylate, 5g of acrylic acid, and 0.275g of reactive hindered amine light stabilizer. Start stirring and replace the air in the reaction vessel with nitrogen. After 10 minutes, start heating and adjust the temperature inside the reaction vessel to 65°C. After the temperature inside the reaction vessel stabilizes, add 0.28g of tert-butyl tert-pentanoate initiator to the reaction vessel in one go, and carry out the polymerization reaction at 65°C for 3 hours.

[0122] After the polymerization reaction was completed, the temperature inside the reaction vessel was maintained at 62℃. 331g of ethyl acetate was added to the reaction vessel with stirring, and the mixture was stirred for 10 minutes. The temperature was then lowered to room temperature to obtain an acrylate polymer dispersed in ethyl acetate solvent. The weight-average molecular weight (Mw) of the polymer, determined by gel permeation chromatography (GPC), was 1.6 million.

[0123] Preparation of component B: Preparation of a fully sealed curing agent

[0124] In a reaction vessel equipped with a stirrer, reflux condenser, thermometer, and nitrogen tube, 240g of HT600 was added, stirring was started, and heating was initiated under nitrogen purging. The temperature inside the reaction vessel was adjusted to 50℃. After the temperature inside the reaction vessel stabilized, methyl ethyl ketone oxime was added dropwise. During the dropwise addition, the reaction temperature was maintained below 55℃, and the dropwise addition time was 30 minutes, with a total of 115g added. The reaction was continuously stirred during the process, and finally a blocked curing agent was obtained, in which the isocyanate group blocking ratio was 100%.

[0125] Preparation of adhesive films for performance evaluation

[0126] The acrylate polymer dispersed in ethyl acetate solvent and all the blocked curing agents were mixed evenly, with a weight ratio of acrylate polymer to all blocked curing agents of 9.5:0.5. The mixture was uniformly coated onto a release film using a manual wire-bar coating method and dried at 60°C for 2 hours, controlling the thickness of the film after drying to be 30±2μm. The film on the release film was then transferred to a cellulose acetate resin film. The release film was peeled off, and a protective release film was placed over the adhesive layer. The cellulose acetate resin film with the adhesive layer was cut into 20cm×30cm pieces, and after peeling off the release film, it was adhered to a glass plate and pressed together. The glass plate with the cellulose acetate resin film was subjected to high-pressure treatment at 100°C and 5 atm for 20 minutes, followed by standing at 100°C / 50%RH for 6 hours, thus completing the optical component for performance evaluation.

[0127] Comparative Example 3

[0128] Except that component B is a non-blocking curing agent, the procedure is the same as in Example 1.

[0129] More specifically, a two-component acrylate adhesive is prepared according to the following method:

[0130] Preparation of component A: Preparation of acrylate polymer

[0131] In a reaction vessel equipped with a stirrer, reflux condenser, thermometer, and nitrogen tube, add 365g of ethyl acetate solvent, 86.22g of benzyl acrylate, 175g of n-butyl acrylate, 10g of 2-hydroxyethyl acrylate, 5g of acrylic acid, and 0.275g of reactive hindered amine light stabilizer. Start stirring and replace the air in the reaction vessel with nitrogen. After 10 minutes, start heating and adjust the temperature inside the reaction vessel to 65°C. After the temperature inside the reaction vessel stabilizes, add 0.28g of tert-butyl tert-pentanoate initiator to the reaction vessel in one go, and carry out the polymerization reaction at 65°C for 3 hours.

[0132] After the polymerization reaction was completed, the temperature inside the reaction vessel was maintained at 62℃. 331g of ethyl acetate was added to the reaction vessel with stirring, and the mixture was stirred for 10 minutes. The temperature was then lowered to room temperature to obtain an acrylate polymer dispersed in ethyl acetate solvent. The weight-average molecular weight (Mw) of the polymer, determined by gel permeation chromatography (GPC), was 1.6 million.

[0133] Preparation of component B: HT600 was used as component B.

[0134] Preparation of adhesive films for performance evaluation

[0135] An acrylate polymer dispersed in ethyl acetate solvent and HT600 were mixed uniformly, with a weight ratio of acrylate polymer to HT600 of 9.5:0.5. The mixture was then uniformly coated onto a release film using a manual wire-bar coating method. After drying at 60°C for 2 hours, the thickness of the film was controlled to be 30±2 μm. The film was then transferred from the release film to a cellulose triacetate resin film. The release film was removed, and a protective release film was placed over the adhesive layer. The cellulose triacetate resin film with the adhesive layer was cut into 20cm×30cm pieces, and after removing the release film, it was adhered to a glass plate and pressed. The glass plate with the cellulose triacetate resin film was subjected to high-pressure treatment at 100°C and 5 atm for 20 minutes, followed by standing at 100°C / 50%RH for 6 hours to prepare the optical component for performance evaluation.

[0136] Comparative Example 4

[0137] Except that a mixed light stabilizer was used instead of a hindered amine light stabilizer that can be polymerized by free radicals during the preparation of component A, the process was carried out in the same manner as in Example 1.

[0138] More specifically, a two-component acrylate adhesive is prepared according to the following method:

[0139] Preparation of component A: Preparation of acrylate polymer

[0140] In a reaction vessel equipped with a stirrer, reflux condenser, thermometer, and nitrogen tube, add 365g of ethyl acetate solvent, 86.22g of benzyl acrylate, 175g of n-butyl acrylate, 10g of 2-hydroxyethyl acrylate, and 5g of acrylic acid. Start stirring and replace the air in the reaction vessel with nitrogen. After 10 minutes, turn on the heater and adjust the temperature inside the reaction vessel to 65°C. After the temperature inside the reaction vessel stabilizes, add 0.28g of tert-butyl tertvalate initiator to the reaction vessel all at once, and carry out the polymerization reaction at 65°C for 3 hours.

[0141] After the polymerization reaction was completed, the temperature inside the reaction vessel was maintained at 62℃. 331g of ethyl acetate and 0.27g of 1024 light stabilizer were added to the reaction vessel while stirring. The mixture was stirred for 10 minutes and then cooled to room temperature to obtain an acrylate polymer dispersed in ethyl acetate solvent. The weight-average molecular weight (Mw) of the polymer, determined by gel permeation chromatography (GPC), was 1.6 million.

[0142] Preparation of component B: Preparation of partially blocked curing agent

[0143] In a reaction vessel equipped with a stirrer, reflux condenser, thermometer, and nitrogen tube, 240g of HT600 was added, stirring was started, and heating was initiated under nitrogen purging. The temperature inside the reaction vessel was adjusted to 50℃. After the temperature inside the reaction vessel stabilized, methyl ethyl ketone oxime was added dropwise. During the dropwise addition, the reaction temperature was maintained below 55℃, and the dropwise addition time was 30 minutes, with a total addition of 60g. The reaction was continuously stirred during the process, and a partially blocked curing agent was finally obtained, in which the isocyanate group blocking ratio was 50%.

[0144] Preparation of adhesive films for performance evaluation

[0145] An acrylate polymer dispersed in ethyl acetate solvent and a partially blocked curing agent were mixed uniformly, with a weight ratio of 9.5:0.5 between the acrylate polymer and the partially blocked curing agent. The mixture was then uniformly coated onto a release film using a manual wire-bar coating method. After drying at 60°C for 2 hours, the thickness of the film was controlled to be 30±2 μm. The film was then transferred from the release film to a cellulose acetate resin film. The release film was removed, and a protective release film was placed over the adhesive layer. The cellulose acetate resin film with the adhesive layer was cut into 20cm×30cm pieces, and after removing the release film, it was adhered to a glass plate and pressed together. The glass plate with the cellulose acetate resin film was subjected to high-pressure treatment at 100°C and 5 atm for 20 minutes, followed by standing at 100°C / 50%RH for 6 hours to prepare the optical component for performance evaluation.

[0146] Comparative Example 5

[0147] Except that a mixture of partially blocked and unblocked trimers was used instead of a blocked curing agent in the preparation of the film, the procedure was carried out in the same manner as in Example 1.

[0148] More specifically, a two-component acrylate adhesive is prepared according to the following method:

[0149] Preparation of component A: Preparation of acrylate polymer

[0150] In a reaction vessel equipped with a stirrer, reflux condenser, thermometer, and nitrogen tube, add 365g of ethyl acetate solvent, 86.22g of benzyl acrylate, 175g of n-butyl acrylate, 10g of 2-hydroxyethyl acrylate, and 5g of acrylic acid. Start stirring and replace the air in the reaction vessel with nitrogen. After 10 minutes, turn on the heater and adjust the temperature inside the reaction vessel to 65°C. After the temperature inside the reaction vessel stabilizes, add 0.28g of tert-butyl tertvalate initiator to the reaction vessel all at once, and carry out the polymerization reaction at 65°C for 3 hours.

[0151] After the polymerization reaction was completed, the temperature inside the reaction vessel was maintained at 62℃. 331g of ethyl acetate and 0.27g of 1024 light stabilizer were added to the reaction vessel while stirring. The mixture was stirred for 10 minutes and then cooled to room temperature to obtain an acrylate polymer dispersed in ethyl acetate solvent. The weight-average molecular weight (Mw) of the polymer, determined by gel permeation chromatography (GPC), was 1.6 million.

[0152] Preparation of component B: Preparation of partially blocked curing agent

[0153] In a reaction vessel equipped with a stirrer, reflux condenser, thermometer, and nitrogen tube, 240g of HT600 was added, stirring was started, and heating was initiated under nitrogen purging. The temperature inside the reaction vessel was adjusted to 50℃. After the temperature inside the reaction vessel stabilized, methyl ethyl ketone oxime was added dropwise. During the dropwise addition, the reaction temperature was maintained below 55℃, and the dropwise addition time was 30 minutes, with a total addition of 60g. The reaction was continuously stirred during the process, and a partially blocked curing agent was finally obtained, in which the isocyanate group blocking ratio was 50%.

[0154] Preparation of adhesive films for performance evaluation

[0155] An acrylate polymer dispersed in ethyl acetate solvent, a partially blocked curing agent, and unblocked HT600 trimer were mixed thoroughly. The mass ratio of the acrylate polymer, the partially blocked curing agent, and the HT600 trimer was 9.5:0.25:0.25. The mixture was then uniformly coated onto a release film using a manual wire-bar coating method. After drying at 60°C for 2 hours, the thickness of the film was controlled to be 30±2 μm. The film was then transferred from the release film to a cellulose acetate resin film. The release film was removed, and a protective release film was placed over the adhesive layer. The cellulose acetate resin film with the adhesive layer was cut into 20cm×30cm pieces, and after removing the release film, it was adhered to a glass plate and pressed. The glass plate with the cellulose acetate resin film was subjected to high-pressure treatment at 100°C and 5 atm for 20 minutes, followed by standing at 100°C / 50%RH for 6 hours. This completed the preparation of the optical component for performance evaluation.

[0156] Comparative Example 6

[0157] Except that the conditions in the film preparation process were replaced with a high-pressure treatment at 60°C and 5 atmospheres for 20 minutes, followed by standing at 60°C and 50% RH for 12 hours, the procedure was carried out in the same manner as in Example 1.

[0158] More specifically, a two-component acrylate adhesive is prepared according to the following method:

[0159] Preparation of component A: Preparation of acrylate polymer

[0160] In a reaction vessel equipped with a stirrer, reflux condenser, thermometer, and nitrogen tube, add 365g of ethyl acetate solvent, 86.22g of benzyl acrylate, 175g of n-butyl acrylate, 10g of 2-hydroxyethyl acrylate, 5g of acrylic acid, and 0.275g of reactive hindered amine light stabilizer. Start stirring and replace the air in the reaction vessel with nitrogen. After 10 minutes, start heating and adjust the temperature inside the reaction vessel to 65°C. After the temperature inside the reaction vessel stabilizes, add 0.28g of tert-butyl tert-pentanoate initiator to the reaction vessel in one go, and carry out the polymerization reaction at 65°C for 3 hours.

[0161] After the polymerization reaction was completed, the temperature inside the reaction vessel was maintained at 62℃. 331g of ethyl acetate was added to the reaction vessel with stirring, and the mixture was stirred for 10 minutes. The temperature was then lowered to room temperature to obtain an acrylate polymer dispersed in ethyl acetate solvent. The weight-average molecular weight (Mw) of the polymer, determined by gel permeation chromatography (GPC), was 1.6 million.

[0162] Preparation of component B: Preparation of a blocked curing agent

[0163] In a reaction vessel equipped with a stirrer, reflux condenser, thermometer, and nitrogen tube, 240g of HT600 was added, stirring was started, and heating was initiated under nitrogen purging. The temperature inside the reaction vessel was adjusted to 50℃. After the temperature inside the reaction vessel stabilized, methyl ethyl ketone oxime was added dropwise. During the dropwise addition, the reaction temperature was maintained below 55℃, and the dropwise addition time was 30 minutes, with a total addition of 60g. The reaction was continuously stirred during the process, and a partially blocked curing agent was finally obtained, in which the isocyanate group blocking ratio was 50%.

[0164] Preparation of adhesive films for performance evaluation

[0165] An acrylate polymer dispersed in ethyl acetate solvent and a partially blocked curing agent were mixed uniformly, with a weight ratio of 9.5:0.5 between the acrylate polymer and the partially blocked curing agent. The mixture was then uniformly coated onto a release film using a manual wire-bar coating method. After drying at 60°C for 2 hours, the thickness of the film was controlled to be 30±2 μm. The film was then transferred from the release film to a cellulose acetate resin film. The release film was removed, and a protective release film was placed over the adhesive layer. The cellulose acetate resin film with the adhesive layer was cut into 20cm×30cm pieces, and after removing the release film, it was adhered to a glass plate and pressed together. The glass plate with the cellulose acetate resin film was subjected to high-pressure treatment at 60°C and 5 atm for 20 minutes, followed by standing at 60°C / 50%RH for 12 hours to prepare the optical component for performance evaluation.

[0166] Comparative Example 7

[0167] Except for replacing the conditions in the film preparation process with 100°C curing, the procedure was carried out in the same manner as in Example 1.

[0168] More specifically, a two-component acrylate adhesive is prepared according to the following method:

[0169] Preparation of component A: Preparation of acrylate polymer

[0170] In a reaction vessel equipped with a stirrer, reflux condenser, thermometer, and nitrogen tube, add 365g of ethyl acetate solvent, 86.22g of benzyl acrylate, 175g of n-butyl acrylate, 10g of 2-hydroxyethyl acrylate, 5g of acrylic acid, and 0.275g of reactive hindered amine light stabilizer. Start stirring and replace the air in the reaction vessel with nitrogen. After 10 minutes, start heating and adjust the temperature inside the reaction vessel to 65°C. After the temperature inside the reaction vessel stabilizes, add 0.28g of tert-butyl tert-pentanoate initiator to the reaction vessel in one go, and carry out the polymerization reaction at 65°C for 3 hours.

[0171] After the polymerization reaction was completed, the temperature inside the reaction vessel was maintained at 62℃. 331g of ethyl acetate was added to the reaction vessel with stirring, and the mixture was stirred for 10 minutes. The temperature was then lowered to room temperature to obtain an acrylate polymer dispersed in ethyl acetate solvent. The weight-average molecular weight (Mw) of the polymer, determined by gel permeation chromatography (GPC), was 1.6 million.

[0172] Preparation of component B: Preparation of partially blocked curing agent

[0173] In a reaction vessel equipped with a stirrer, reflux condenser, thermometer, and nitrogen tube, 240g of HT600 was added, stirring was started, and heating was initiated under nitrogen purging. The temperature inside the reaction vessel was adjusted to 50℃. After the temperature inside the reaction vessel stabilized, methyl ethyl ketone oxime was added dropwise. During the dropwise addition, the reaction temperature was maintained below 55℃, and the dropwise addition time was 30 minutes, with a total addition of 60g. The reaction was continuously stirred during the process, and finally a blocked curing agent was obtained, in which the isocyanate group blocking ratio was 50%.

[0174] Preparation of adhesive films for performance evaluation

[0175] An acrylate polymer and a blocking curing agent dispersed in ethyl acetate solvent were mixed evenly, with a weight ratio of 9.5:0.5 between the acrylate polymer and the partially blocking curing agent. The mixture was then uniformly coated onto a release film using a manual wire-bar coating method. After drying at 100°C for 2 hours, the thickness of the film was controlled to be 30±2 μm. The film was then transferred from the release film to a cellulose acetate resin film. The release film was removed, and a protective release film was placed over the adhesive layer. The cellulose acetate resin film with the adhesive layer was cut into 20cm×30cm pieces, and after removing the release film, it was adhered to a glass plate and pressed together. The glass plate with the cellulose acetate resin film was subjected to high-pressure treatment at 100°C and 5 atmospheres for 20 minutes, followed by standing at 100°C / 50%RH for 6 hours to prepare the optical component for performance evaluation.

[0176] Comparative Example 8 (partially blocked curing agent with a blocking ratio of 30%)

[0177] Two-component acrylic adhesives for optical components are prepared according to the following method:

[0178] Preparation of component A: Preparation of acrylate polymer

[0179] In a reaction vessel equipped with a stirrer, reflux condenser, thermometer, and nitrogen tube, add 365g of ethyl acetate solvent, 86.22g of benzyl acrylate, 175g of n-butyl acrylate, 10g of 2-hydroxyethyl acrylate, 5g of acrylic acid, and 0.275g of reactive hindered amine light stabilizer. Start stirring and replace the air in the reaction vessel with nitrogen. After 10 minutes, start heating and adjust the temperature inside the reaction vessel to 65°C. After the temperature inside the reaction vessel stabilizes, add 0.28g of tert-butyl tert-pentanoate initiator to the reaction vessel in one go, and carry out the polymerization reaction at 65°C for 3 hours.

[0180] After the polymerization reaction was completed, the temperature inside the reaction vessel was maintained at 62℃. 331g of ethyl acetate was added to the reaction vessel with stirring, and the mixture was stirred for 10 minutes. The temperature was then lowered to room temperature to obtain an acrylate polymer dispersed in ethyl acetate solvent. The weight-average molecular weight (Mw) of the polymer, determined by gel permeation chromatography (GPC), was 1.6 million.

[0181] Preparation of component B: Preparation of partially blocked curing agent

[0182] In a reaction vessel equipped with a stirrer, reflux condenser, thermometer, and nitrogen tube, 240g of HT600 was added, stirring was started, and heating was initiated under nitrogen purging. The temperature inside the reaction vessel was adjusted to 50℃. After the temperature inside the reaction vessel stabilized, methyl ethyl ketone oxime was added dropwise. During the dropwise addition, the reaction temperature was maintained below 55℃, and the dropwise addition time was 30 minutes, with a total addition of 35g. The reaction was continuously stirred during the process, and a partially blocked curing agent was finally obtained, in which the isocyanate group blocking ratio was 30%.

[0183] Preparation of adhesive films for performance evaluation

[0184] An acrylate polymer dispersed in ethyl acetate solvent and a partially blocked curing agent were mixed uniformly, with a weight ratio of 9.5:0.5 between the acrylate polymer and the partially blocked curing agent. The mixture was then uniformly coated onto a release film using a manual wire-bar coating method. After drying at 60°C for 2 hours, the thickness of the film was controlled to be 30±2 μm. The film was then transferred from the release film to a cellulose acetate resin film. The release film was removed, and a protective release film was placed over the adhesive layer. The cellulose acetate resin film with the adhesive layer was cut into 20cm×30cm pieces, and after removing the release film, it was adhered to a glass plate and pressed together. The glass plate with the cellulose acetate resin film was subjected to high-pressure treatment at 100°C and 5 atm for 20 minutes, followed by standing at 100°C / 50%RH for 6 hours to prepare the optical component for performance evaluation.

[0185] Comparative Example 9 (partially blocked curing agent with a blocking ratio of 70%)

[0186] Two-component acrylic adhesives for optical components are prepared according to the following method:

[0187] Preparation of component A: Preparation of acrylate polymer

[0188] In a reaction vessel equipped with a stirrer, reflux condenser, thermometer, and nitrogen tube, add 365g of ethyl acetate solvent, 86.22g of benzyl acrylate, 175g of n-butyl acrylate, 10g of 2-hydroxyethyl acrylate, 5g of acrylic acid, and 0.275g of reactive hindered amine light stabilizer. Start stirring and replace the air in the reaction vessel with nitrogen. After 10 minutes, start heating and adjust the temperature inside the reaction vessel to 65°C. After the temperature inside the reaction vessel stabilizes, add 0.28g of tert-butyl tert-pentanoate initiator to the reaction vessel in one go, and carry out the polymerization reaction at 65°C for 3 hours.

[0189] After the polymerization reaction was completed, the temperature inside the reaction vessel was maintained at 62℃. 331g of ethyl acetate was added to the reaction vessel with stirring, and the mixture was stirred for 10 minutes. The temperature was then lowered to room temperature to obtain an acrylate polymer dispersed in ethyl acetate solvent. The weight-average molecular weight (Mw) of the polymer, determined by gel permeation chromatography (GPC), was 1.6 million.

[0190] Preparation of component B: Preparation of partially blocked curing agent

[0191] In a reaction vessel equipped with a stirrer, reflux condenser, thermometer, and nitrogen tube, 240g of HT600 was added, stirring was started, and heating was initiated under nitrogen purging. The temperature inside the reaction vessel was adjusted to 50℃. After the temperature inside the reaction vessel stabilized, methyl ethyl ketone oxime was added dropwise. During the dropwise addition, the reaction temperature was maintained below 55℃, and the dropwise addition time was 30 minutes, with a total addition of 80g. The reaction was continuously stirred during the process, and a partially blocked curing agent was finally obtained, in which the isocyanate group blocking ratio was 70%.

[0192] Preparation of adhesive films for performance evaluation

[0193] An acrylate polymer dispersed in ethyl acetate solvent and a partially blocked curing agent were mixed uniformly, with a weight ratio of 9.5:0.5 between the acrylate polymer and the partially blocked curing agent. The mixture was then uniformly coated onto a release film using a manual wire-bar coating method. After drying at 60°C for 2 hours, the thickness of the film was controlled to be 30±2 μm. The film was then transferred from the release film to a cellulose acetate resin film. The release film was removed, and a protective release film was placed over the adhesive layer. The cellulose acetate resin film with the adhesive layer was cut into 20cm×30cm pieces, and after removing the release film, it was adhered to a glass plate and pressed together. The glass plate with the cellulose acetate resin film was subjected to high-pressure treatment at 100°C and 5 atm for 20 minutes, followed by standing at 100°C / 50%RH for 6 hours to prepare the optical component for performance evaluation.

[0194] Comparative Example 10 (excess meth)acrylic acid)

[0195] Two-component acrylic adhesives for optical components are prepared according to the following method:

[0196] Preparation of component A: Preparation of acrylate polymer

[0197] In a reaction vessel equipped with a stirrer, reflux condenser, thermometer, and nitrogen tube, add 365g of ethyl acetate solvent, 86.22g of benzyl acrylate, 175g of n-butyl acrylate, 10g of 2-hydroxyethyl acrylate, 10g of acrylic acid, and 0.275g of reactive hindered amine light stabilizer (commercially available, Adico hindered amine light stabilizer LA-82; unless otherwise specified, the same reactive hindered amine light stabilizer is used in other examples). Start stirring, replace the air in the reaction vessel with nitrogen, and after 10 minutes, start heating and adjust the temperature inside the reaction vessel to 65°C. After the temperature inside the reaction vessel stabilizes, add 0.28g of initiator tert-butyl pentovalerate to the reaction vessel in one go, and carry out the polymerization reaction at 65°C for 3 hours.

[0198] After the polymerization reaction was completed, the temperature inside the reaction vessel was maintained at 62℃. 331g of ethyl acetate was added to the reaction vessel with stirring, and the mixture was stirred for 10 minutes. The temperature was then lowered to room temperature to obtain an acrylate polymer dispersed in ethyl acetate solvent. The weight-average molecular weight (Mw) of the polymer, determined by gel permeation chromatography (GPC), was 1.6 million.

[0199] Preparation of component B: Preparation of partially blocked curing agent

[0200] In a reaction vessel equipped with a stirrer, reflux condenser, thermometer, and nitrogen tube, 240g of HT600 (curing agent) was added. Stirring was started, and under nitrogen purging, heating was initiated. The temperature inside the reaction vessel was adjusted to 50°C. After the temperature inside the reaction vessel stabilized, methyl ethyl ketone oxime was added dropwise. During the dropwise addition, the reaction temperature was maintained below 55°C. The dropwise addition time was 30 minutes, with a total addition of 60g. The reaction was continuously stirred during the process, and a partially blocked curing agent was finally obtained, in which the isocyanate group blocking ratio was 50%.

[0201] Preparation of adhesive films for performance evaluation

[0202] An acrylate polymer dispersed in ethyl acetate solvent and a partially blocked curing agent were mixed uniformly, with a weight ratio of 9.5:0.5 between the acrylate polymer and the partially blocked curing agent. The mixture was then uniformly coated onto a release film using a manual wire-bar coating method. After drying at 60°C for 2 hours, the thickness of the film was controlled to be 30±2 μm. The film was then transferred from the release film to a cellulose acetate resin film. The release film was removed, and a protective release film was placed over the adhesive layer. The cellulose acetate resin film with the adhesive layer was cut into 20cm×30cm pieces, and after removing the release film, it was adhered to a glass plate and pressed together. The glass plate with the cellulose acetate resin film was subjected to high-pressure treatment at 100°C and 5 atm for 20 minutes, followed by standing at 100°C / 50%RH for 6 hours to prepare the optical component for performance evaluation.

[0203] Comparative Example 11 (excess of hydroxyl-containing (meth)acrylate monomer)

[0204] Two-component acrylic adhesives for optical components are prepared according to the following method:

[0205] Preparation of component A: Preparation of acrylate polymer

[0206] In a reaction vessel equipped with a stirrer, reflux condenser, thermometer, and nitrogen tube, add 365g of ethyl acetate solvent, 86.22g of benzyl acrylate, 175g of n-butyl acrylate, 20g of 2-hydroxyethyl acrylate, 5g of acrylic acid, and 0.275g of reactive hindered amine light stabilizer (commercially available, Idico hindered amine light stabilizer LA-82; unless otherwise specified, the same reactive hindered amine light stabilizer is used in other examples). Start stirring, replace the air in the reaction vessel with nitrogen, and after 10 minutes, start heating and adjust the temperature inside the reaction vessel to 65°C. After the temperature inside the reaction vessel stabilizes, add 0.28g of initiator tert-butyl tert-pentanoate to the reaction vessel in one go, and carry out the polymerization reaction at 65°C for 3 hours.

[0207] After the polymerization reaction was completed, the temperature inside the reaction vessel was maintained at 62℃. 331g of ethyl acetate was added to the reaction vessel with stirring, and the mixture was stirred for 10 minutes. The temperature was then lowered to room temperature to obtain an acrylate polymer dispersed in ethyl acetate solvent. The weight-average molecular weight (Mw) of the polymer, determined by gel permeation chromatography (GPC), was 1.6 million.

[0208] Preparation of component B: Preparation of partially blocked curing agent

[0209] In a reaction vessel equipped with a stirrer, reflux condenser, thermometer, and nitrogen tube, 240g of HT600 (curing agent) was added. Stirring was started, and under nitrogen purging, heating was initiated. The temperature inside the reaction vessel was adjusted to 50°C. After the temperature inside the reaction vessel stabilized, methyl ethyl ketone oxime was added dropwise. During the dropwise addition, the reaction temperature was maintained below 55°C. The dropwise addition time was 30 minutes, with a total addition of 60g. The reaction was continuously stirred during the process, and a partially blocked curing agent was finally obtained, in which the isocyanate group blocking ratio was 50%.

[0210] Preparation of adhesive films for performance evaluation

[0211] An acrylate polymer dispersed in ethyl acetate solvent and a partially blocked curing agent were mixed uniformly, with a weight ratio of 9.5:0.5 between the acrylate polymer and the partially blocked curing agent. The mixture was then uniformly coated onto a release film using a manual wire-bar coating method. After drying at 60°C for 2 hours, the thickness of the film was controlled to be 30±2 μm. The film was then transferred from the release film to a cellulose acetate resin film. The release film was removed, and a protective release film was placed over the adhesive layer. The cellulose acetate resin film with the adhesive layer was cut into 20cm×30cm pieces, and after removing the release film, it was adhered to a glass plate and pressed together. The glass plate with the cellulose acetate resin film was subjected to high-pressure treatment at 100°C and 5 atm for 20 minutes, followed by standing at 100°C / 50%RH for 6 hours to prepare the optical component for performance evaluation.

[0212] The samples provided in Examples 1 to 5 and Comparative Examples 1 to 11 were comprehensively evaluated according to the above testing methods. The evaluation results are shown in Table 2 below:

[0213] Table 2: Performance Evaluation Data

[0214]

[0215] The performance is scored according to each item, with 1 to 5 representing performance from low to high, and 0 representing the loss of this performance.

[0216] Based on the performance data in Table 2 above, and comparing Examples 1 and 4, hindered amine light stabilizers containing double bond groups were grafted onto the acrylate polymer molecular chains via polymerization to form permanently light-stabilized polymers with hindered amine functional groups. This type of light stabilizer effectively avoids loss due to physical migration or volatilization, improves and enhances the dispersion performance and light stabilization effect of the hindered amine light stabilizer in the polymer, allowing the film to maintain excellent light stability even under prolonged high-temperature operating conditions—something that conventional physical mixing cannot achieve.

[0217] Simultaneously, a combination of partial end-capping curing agent and acrylic adhesive is used, employing a two-step curing process. In the first curing step, the hydroxyl groups in the linear polymer acrylic resin react with the exposed isocyanate to produce a large-molecule linear adhesive. During the application process, the coating is peeled off and cut, and the film retains a certain strength, allowing for complete peeling. After application, a further high-temperature curing process is performed, at which point the sealed isocyanate is unsealed, continuing micro-crosslinking. This further enhances the film strength and improves reliability under high temperature and humidity conditions, resolving the issue of shrinkage and deformation in high humidity environments. The high temperature and humidity resistance is thus further improved.

[0218] This invention illustrates a two-component acrylate adhesive for optical components and its preparation method through the above embodiments. However, this invention is not limited to the above embodiments, meaning that this invention does not necessarily rely on the above embodiments for implementation. Those skilled in the art should understand that any improvements to this invention, equivalent substitutions of the raw materials in the product of this invention, addition of auxiliary components, and selection of specific methods, etc., all fall within the protection scope and disclosure scope of this invention.

Claims

1. A two-component acrylic adhesive comprising component A and component B, wherein, Component A contains an acrylate polymer (a) dispersed in a solvent. Component B is a partially blocked isocyanate curing agent (b). Among them, the acrylate copolymer (a) is a copolymer comprising units derived from (meth)acrylic acid monomers, units derived from (meth)acrylic acid aryl ester monomers, units derived from (meth)acrylic acid ester monomers containing hydroxyl groups, units derived from (meth)acrylic acid alkyl ester monomers, and units derived from hindered amine light stabilizers that can be polymerized by free radicals. The partially blocked isocyanate curing agent (b) is a reaction product of isocyanate trimer and ketoxime, and the blocked isocyanate groups therein account for 35%~65%. In the preparation of the acrylate polymer (a), relative to the total weight of 100 wt% of the monomers used in the preparation component A, the amount of the (meth)acrylate monomer is 1 wt% to 3 wt%, the amount of the (meth)acrylate aryl ester monomer is 3 wt% to 40 wt%, the amount of the hydroxyl-containing (meth)acrylate monomer is 3 wt% to 5 wt%, and the amount of the (meth)acrylate alkyl ester is 60 wt% to 70 wt%. The content of the acrylate polymer (a) is 90-95 parts by weight, and the content of the partially blocked isocyanate curing agent (b) is 5-10 parts by weight. The amount of the hindered amine light stabilizer that can be polymerized by free radicals is 0.01 wt% to 0.5 wt% relative to the total weight of 100 wt% of the monomers used in the preparation of component A.

2. The two-component acrylate adhesive according to claim 1, wherein, The partially blocked isocyanate curing agent (b) is a reaction product of isocyanate trimer and ketoxime, and the isocyanate group blocking ratio is 40%~60%.

3. The two-component acrylate adhesive according to claim 1, wherein, The acrylate polymer (a) has a weight-average molecular weight of 1 million to 3 million; and / or The solid content of component A is 10 wt% to 30 wt%.

4. The two-component acrylate adhesive according to claim 3, wherein, The acrylate polymer (a) has a weight-average molecular weight of 1 million to 2 million; and / or The solid content of component A is 15 wt%~25 wt%.

5. The two-component acrylate adhesive according to claim 1, wherein, The aryl monomer of (meth)acrylate is (meth)acrylate C6~C6. 12 Aryl esters; and / or The hydroxyl-containing (meth)acrylate monomer is a (meth)acrylate hydroxy C1-C6 alkyl ester; and / or The alkyl methacrylate is (meth)acrylic acid C1~C1. 12 Alkyl esters; and / or The structure of the hindered amine light stabilizer that can be polymerized by free radicals is as follows: 。 6. The two-component acrylate adhesive according to claim 1, wherein, The aryl methacrylate monomer is selected from one or more of benzyl methacrylate, phenyl methacrylate, and phenoxyethyl methacrylate; and / or The hydroxyl-containing (meth)acrylate monomer is one or more selected from 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and 6-hydroxyhexyl (meth)acrylate; and / or The alkyl methacrylate is selected from one or more of methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, tert-butyl methacrylate, pentyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, n-octyl methacrylate, isooctyl methacrylate, n-nonyl methacrylate, isononyl methacrylate, n-decyl methacrylate, isodecyl methacrylate, undecyl methacrylate, and lauryl methacrylate.

7. The two-component acrylate adhesive according to claim 1, wherein, The weight ratio of isocyanate trimer to ketoxime is 1 to 10:

1.

8. The two-component acrylate adhesive according to claim 7, wherein, The amount of the hindered amine light stabilizer that can be polymerized by free radicals is 0.1wt%~0.2wt%; and / or The weight ratio of isocyanate trimer to ketoxime is 3.5 to 5:

1.

9. The two-component acrylate adhesive according to claim 1, wherein, The ketoxime is one or more selected from methyl ethyl ketone oxime, acetone oxime, and cyclohexanone oxime; and / or The isocyanate trimer is an HDI trimer; and / or The solvent in component A is selected from one or more of the following: aromatic hydrocarbon solvents, aliphatic hydrocarbon solvents, alicyclic hydrocarbon solvents, ether solvents, halogenated hydrocarbon solvents, ester solvents, ketone solvents, and nitrile solvents.

10. The two-component acrylate adhesive according to claim 9, wherein, The ketoxime is methyl ethyl ketone oxime.

11. A method for preparing a two-component acrylate adhesive according to any one of claims 1 to 10, comprising the following steps: Step 1), Preparation of component A: In the presence of a solvent, acrylic monomer, aryl (meth)acrylate monomer, hydroxyl-containing (meth)acrylate monomer, alkyl (meth)acrylate and hindered amine light stabilizer that can be polymerized by free radical polymerization are polymerized in the presence of an initiator to obtain acrylate polymer (a). Step 2), Preparation of component B: The isocyanate trimer and ketoxime are reacted to obtain a partially blocked isocyanate curing agent (b).

12. The method for preparing a two-component acrylate adhesive according to claim 11, wherein, The polymerization method in step 1) is solution polymerization; and / or The solvent in step 1) is selected from one or more of aromatic hydrocarbon solvents, aliphatic hydrocarbon solvents, alicyclic hydrocarbon solvents, ether solvents, halogenated hydrocarbon solvents, ester solvents, ketone solvents and nitrile solvents.

13. The method for preparing a two-component acrylate adhesive according to claim 11 or 12, wherein, The aggregation in step 1) is performed as follows: In an inert atmosphere, acrylic monomers, aryl (meth)acrylate monomers, hydroxyl-containing (meth)acrylate monomers, alkyl (meth)acrylates, and hindered amine light stabilizers capable of free radical polymerization are added to a solvent. The mixture is heated to 60-80°C, then an initiator is added, and the polymerization reaction is carried out at a constant temperature; and / or The amount of initiator relative to 100 wt% of monomer is 0.01 wt% to 0.5 wt%; and / or The initiator is a thermal initiator and / or a redox initiator; and / or The reaction in step 2) proceeds as follows: The reaction was carried out by adding ketoxime dropwise to the isocyanate trimer under an inert atmosphere.

14. The method for preparing a two-component acrylate adhesive according to claim 13, wherein, The amount of initiator used is 0.05wt%~0.2wt%; and / or The reaction temperature for step 2) is 40~60℃.

15. Use of the two-component acrylate adhesive according to any one of claims 1 to 10 in bonding optical components.

16. A method for applying a two-component acrylic adhesive according to any one of claims 1 to 10, comprising the following steps: 2-1) Mix component A and component B evenly to obtain an adhesive composition, wherein, The content of acrylate polymer (a) in component A is 90-95 parts by weight, and the content of partially blocked isocyanate curing agent (b) in component B is 5-10 parts by weight. 2-2) The adhesive composition obtained in step 2-1) is coated to form a uniform coating, and dried at a temperature of 40~70°C to obtain an adhesive film; 2-3) Place the adhesive film obtained in step 2-2) between the objects to be adhered and perform high pressure treatment for 20 minutes at 90~110℃ and 5~7 atmospheres, and then cure at 90~110℃.

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