Boron-containing organic silicon, optical adhesive, organic silicon OCA and preparation method and application thereof

Abstract

The invention provides boron-containing organic silicon, an optical adhesive, organic silicon OCA and a preparation method and application thereof. The preparation raw materials of the boron-containing organic silicon comprise a combination of silanol, a siloxane monomer and a boric acid compound. In the raw materials for preparing the boron-containing organic silicon, the ratio of the total molar weight of hydroxyl to the total molar weight of alkoxy is (0.8-1.1): 1, and the ratio of the total molar weight of the element B to the total molar weight of the element Si is 1: (5-11.5). According to the boron-containing organic silicon provided by the invention, through the design of the preparation raw materials, the compatibility between the boron-containing organic silicon and an organic silicon material in an optical adhesive is good, the tackifying effect on the optical adhesive is excellent, and the boron-containing organic silicon has excellent low-temperature resistance and high-temperature and high-humidity resistance.

Description

Technical Field

[0001] The present invention belongs to the technical field of organosilicon packaging materials, and in particular relates to boron-containing organosilicon, optical adhesive, organosilicon OCA and preparation methods and applications thereof. Background Art

[0002] OCA optical adhesive is a double-sided adhesive tape with no substrate material and a release film attached to the upper and lower bottom layers of the adhesive layer. It is a type of pressure-sensitive adhesive and is widely used in the field of optical display, such as for bonding display modules, glass cover plates, touch screens and other display units. It has the characteristics of high light transmittance and high bonding strength. At present, OCA optical adhesive can be divided into acrylate OCA, silicone OCA, polyurethane OCA, epoxy resin OCA, etc. according to the type of materials used. Compared with the other types of OCA, silicone OCA has better weather resistance, yellowing resistance, aging resistance, and easy rework. However, silicone OCA currently generally has poor initial adhesion, and its peel strength is much lower than other resins. If the initial adhesion is too low, it cannot be transferred immediately after the bonding is completed, resulting in low production efficiency, and the bonding components are prone to fall off during the transfer of the display, causing losses.

[0003] At present, adding tackifiers to silicone materials is a common method to solve the problem of adhesion between materials and substrates. However, in the actual production process, conventional tackifiers have poor compatibility with silicone materials and have no obvious tackifying effect on the substrate. Under certain temperature and humidity, the bonding force decreases significantly, resulting in serious separation between the silicone resin material and the substrate.

[0004] CN102775611A discloses a tackifier and a production method thereof, wherein the light yellow liquid silicone tackifier is obtained by reacting hydroxy silicone oil, γ-glycidyloxypropyltrimethoxysilane and γ-methylpropionyloxypropyltrimethoxysilane under the catalytic action of organotin; however, the organotin catalyst in the tackifier is difficult to completely remove, which seriously affects the normal curing of addition-type liquid silicone rubber.

[0005] CN104774333A discloses a thickener for addition-type silicone rubber prepared by catalytic reaction of vinyl hydroxy silicone oil, glycidyl ether alkoxy silane and titanate. However, titanate, especially titanate complex, is generally yellow or even dark brown. The prepared thickener is colored, which may have an adverse effect on the preparation of colorless or light-colored addition-type organic silicone adhesives.

[0006] CN109824899A discloses an addition-type thickener for silica gel, which is prepared by reacting epoxydialkoxysilane, boric acid and vinyldialkoxysilane under the catalysis of alkaline anion exchange resin. However, the ion exchange resin may break during the reaction, and there is a risk of incomplete filtration when the catalyst is subsequently removed by vacuum filtration.

[0007] Therefore, it is urgent to design a tackifier that has good compatibility with silicone materials, excellent tackifying effect, and can improve the low temperature resistance and high temperature and humidity resistance of silicone OCA. Summary of the invention

[0008] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a boron-containing organosilicon, an optical adhesive, an organosilicon OCA and a preparation method and application thereof. By designing the preparation raw materials, the boron-containing organosilicon has good compatibility with the organosilicon material in the optical adhesive, has an excellent viscosity-enhancing effect on the optical adhesive, and has excellent low temperature resistance and high temperature and humidity resistance.

[0009] To achieve this object, the present invention adopts the following technical solutions:

[0010] In a first aspect, the present invention provides a boron-containing organosilicon, wherein the raw materials for preparing the boron-containing organosilicon include a combination of silanol, siloxane monomer and boric acid compound; in the raw materials for preparing the boron-containing organosilicon, the ratio of the total molar amount of hydroxyl groups to the total molar amount of alkoxy groups is (0.8-1.1):1, and the ratio of the total molar amount of B element to the total molar amount of Si element is 1:(5-11.5).

[0011] The present invention forms a boron-containing organosilicon polymer macromolecule, i.e., boron-containing organosilicon, through siloxane monomers, silanols, and boric acid compounds, and the target product structure is more controllable and has no by-products. Since the B atom has an electron vacancy, it can be used as an acceptor of unpaired electrons on the polysiloxane chain segment or on the surface of the substrate, forming an electron bridge between adjacent molecules, thereby forming a weak bond link, and the molecular structure of the boron-containing organosilicon provided by the present invention contains Si-OB bonds, which can physically crosslink the organosilicon OCA with the substrate to a certain extent, so the boron-containing organosilicon provided by the present invention is added to the optical adhesive, so that the optical adhesive can have good bonding properties with glass, ink, and polarizer after curing; in addition, the introduction of the B element can destroy the regularity of the chain segment, thereby reducing the Tg of the boron-containing organosilicon and improving the low temperature resistance of the organosilicon OCA.

[0012] The boron-containing organosilicon provided by the present invention contains no catalyst in the raw materials for preparation, thus avoiding to a certain extent the adverse effects of catalyst residues on the color, curing and other aspects of the optical adhesive; the present invention effectively regulates the structure of the boron-containing organosilicon by introducing silanol, controls the molar ratio of hydroxyl to alkoxy in the reaction system, promotes the thorough condensation reaction, improves the yield of the boron-containing organosilicon, and at the same time reduces the residual amount of alkoxy in the boron-containing organosilicon, thus avoiding the boron-containing organosilicon fogging caused by hydrolysis of alkoxy during subsequent use and storage, which cannot meet the use requirements of the optical adhesive; in addition, compared with fatty alcohols, silanols have better compatibility with siloxane monomers and boric acid compounds, do not separate into phases after feeding, and react more thoroughly; compared with hydroxy silicone oils, silanols have higher reaction activity, can form a tighter network structure, and effectively enhance the hydrolysis resistance of the boron-containing organosilicon to a certain extent.

[0013] In the present invention, "the ratio of the total molar amount of hydroxyl groups to the total molar amount of alkoxy groups in the preparation raw materials of the boron-containing organosilicon is (0.8-1.1):1" means that the ratio of the total molar amount of hydroxyl groups to the total molar amount of alkoxy groups contained in all the preparation raw materials of the boron-containing organosilicon is (0.8-1.1):1; "the ratio of the total molar amount of element B to the total molar amount of element Si is 1:(5-11.5)" means that the ratio of the total molar amount of element B to the total molar amount of element Si contained in all the preparation raw materials of the boron-containing organosilicon is 1:(5-11.5).

[0014] In the raw materials for preparing the boron-containing organosilicon, hydroxyl groups are derived from silanol silanols and boron hydroxyl groups of boric acid compounds, and the ratio of the total molar amount of hydroxyl groups to the total molar amount of alkoxy groups is (0.8-1.1):1, for example, it can be 0.82:1, 0.84:1, 0.86:1, 0.88:1, 0.9:1, 0.92:1, 0.94:1, 0.96:1, 0.98:1, 1:1, 1.02:1, 1.04:1, 1.06:1, 1.08:1, etc.

[0015] In the preparation raw materials of the boron-containing organosilicon, the ratio of the total molar amount of the B element to the total molar amount of the Si element is 1:(5-11.5), for example, it can be 1:5.1, 1:5.2, 1:5.5, 1:6, 1:6.5, 1:7, 1:7.5, 1:8, 1:8.5, 1:9, 1:9.5, 1:10, 1:10.5, 1:11, etc.

[0016] The present invention controls the molar ratio of the B element to the Si element in the preparation raw material of the boron-containing organosilicon within a suitable range, so as to obtain the boron-containing organosilicon with good adhesion promoting effect and no significant change in hydrolysis resistance. If the molar ratio of the B element to the Si element is too large, the bonding performance of the optical adhesive is improved but the hydrolysis resistance is deteriorated, because the BO-Si bond is more sensitive to hydrolysis than the Si-O-Si bond and is more easily hydrolyzed and broken; if the molar ratio of the B element to the Si element is too small, the improvement of the adhesion performance of the organosilicon OCA is not obvious.

[0017] The following are preferred technical solutions of the present invention, but are not intended to limit the technical solutions provided by the present invention. Through the following preferred technical solutions, the objectives and beneficial effects of the present invention can be better achieved and realized.

[0018] As a preferred technical solution, the general formula of the silanol is R 11 4-a Si(OH) a ; Among them, R 11 Each is independently selected from any one of C1-C5 straight or branched alkyl, C3-C8 cyclic hydrocarbon group; a is 2 or 3.

[0019] In the present invention, "each independently" means that when there are multiple subjects, they can be the same or different from each other, and the same descriptions mentioned below have the same meaning.

[0020] Preferably, the silanol includes any one of dimethylsilanediol, methylethylsilanediol, methylphenylsilanediol, methylsilanetriol or phenylsilanetriol, or a combination of at least two thereof.

[0021] Preferably, the general formula of the siloxane monomer is R 12 4-b Si(OR 13 ) b ; Among them, R 12 Each is independently selected from any one of a C2-C6 unsaturated hydrocarbon group, a C1-C5 straight chain or branched alkyl group; R 13 Each is independently selected from any one of C1-C5 straight or branched alkyl groups; b is selected from an integer of 1-3, more preferably 2 or 3.

[0022] In the present invention, the C1-C5 can be independently C2, C3, C4, etc.

[0023] The C3-C8 can each independently be C4, C5, C6, C7, etc.

[0024] The C1-C5 straight or branched chain alkyl groups include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, 2-methylbutyl, n-pentyl, isopentyl, neopentyl, and the like.

[0025] The C3-C8 cycloalkyl group includes any one of a C3-C8 cycloalkyl group or a phenyl group; the C3-C8 cycloalkyl group illustratively includes but is not limited to: a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, and the like.

[0026] The C2-C6 unsaturated hydrocarbon group includes any one of the C2-C6 alkenyl groups, illustratively including but not limited to ethenyl, propenyl, butenyl and the like.

[0027] Preferably, the siloxane monomer comprises a first siloxane monomer, a second siloxane monomer and optionally a third siloxane monomer; the general formula of the first siloxane monomer is R A1 2Si(OR A2 )2; the general formula of the second siloxane monomer is R B1 Si(OR B2 )3; the general formula of the third siloxane monomer is R C1 3SiOR C2 ; Among them, R A1 , R B1 , R C1 Each is independently selected from any one of a C2-C6 unsaturated hydrocarbon group, a C1-C5 straight chain or branched alkyl group; R A2 , R B2 , R C2 Each is independently selected from any one of C1-C5 straight chain or branched chain alkyl groups.

[0028] Preferably, the first siloxane monomer includes any one of methylvinyldimethoxysilane, dimethyldimethoxysilane or dimethyldiethoxysilane, or a combination of at least two thereof.

[0029] Preferably, the second siloxane monomer includes methyltrimethoxysilane and / or methyltriethoxysilane.

[0030] Preferably, the third siloxane monomer comprises trimethylmethoxysilane.

[0031] Preferably, the boric acid compound includes any one of boric acid, phenylboric acid or tetrahydroxyboron, or a combination of at least two thereof.

[0032] Preferably, the molar ratio of the hydroxyl group in the boric acid compound to the hydroxyl group in the silanol is 1:(1-7), for example, it can be 1:1, 1:1.5, 1:2, 1:2.5, 1:3, 1:3.5, 1:4, 1:4.5, 1:5, 1:5.5, 1:6, etc.

[0033] Preferably, in the preparation raw material of the boron-containing organosilicon, the ratio of the total molar amount of the B element to the total molar amount of the Si element is 1:(6.5-11.5) (for example, 1:6.6, 1:6.8, 1:7, 1:7.2, 1:7.4, 1:7.6, 1:7.8, 1:8.2, 1:8.6, 1:9.2, 1:9.4, 1:10.2, 1:10.6, 1:11.2, 1:11.4, etc.), and further preferably 1:(7-8.5) (for example, 1:7.1, 1:7.3, 1:7.7, 1:7.9, 1:8.1, 1:8.3, 1:8.4, etc.).

[0034] When the molar ratio of the B element to the Si element in the raw material for preparing the boron-containing organosilicon of the present invention is 1:(7-8.5), the hydrolysis resistance of the boron-containing organosilicon can be optimized, and the bonding performance of the organosilicon OCA can be improved.

[0035] Preferably, the raw materials for preparing the boron-containing organosilicon also include a solvent.

[0036] Preferably, the solvent includes any one of N,N-dimethylformamide, dimethyl sulfoxide, methanol, acetonitrile, isopropanol, 1,4-dioxane or cyclohexanone, or a combination of at least two thereof.

[0037] Preferably, based on the total mass of the silanol, siloxane monomer and boric acid compound as 100%, the mass of the solvent is 25-40%, for example, it can be 25.5%, 26%, 26.5%, 27%, 27.5%, 28%, 28.5%, 29%, 29.5%, 30%, 30.5%, 31%, 31.5%, 32%, 32.5%, 33%, 33.5%, 34%, 34.5%, 35%, 35.5%, 36%, 36.5%, 37%, 37.5%, 38%, 39% and the like.

[0038] In a second aspect, the present invention provides a method for preparing the boron-containing organosilicon as described in the first aspect, the preparation method comprising:

[0039] The boron-containing organosilicon is obtained by reacting silanol and siloxane monomers with boric acid compounds.

[0040] The boron-containing organosilicon is prepared by the preparation method provided by the invention, with high yield and no by-products, and the yield is 72-87%.

[0041] Preferably, the reaction temperature is 80-140°C, for example, 85°C, 90°C, 95°C, 100°C, 105°C, 110°C, 115°C, 120°C, 125°C, 130°C, 135°C, etc.

[0042] Preferably, the reaction time is 3-7 h, for example, 3.2 h, 3.5 h, 3.8 h, 4 h, 4.2 h, 4.5 h, 4.8 h, 5 h, 5.2 h, 5.5 h, 5.8 h, 6 h, 6.2 h, 6.5 h, 6.8 h, etc.

[0043] Preferably, the reaction is carried out in the presence of a solvent.

[0044] Preferably, after the reaction is completed, a reduced pressure distillation step is further included to remove the solvent in the reaction system.

[0045] In a third aspect, the present invention provides a use of the boron-containing organosilicon as described in the first aspect, wherein the boron-containing organosilicon is used as a tackifier in an optical adhesive.

[0046] In a fourth aspect, the present invention provides an optical adhesive, wherein the raw materials for preparing the optical adhesive include, by weight:

[0047]

[0048] The vinyl silicone resin is 10-30 parts by weight, for example, 12 parts by weight, 14 parts by weight, 16 parts by weight, 18 parts by weight, 20 parts by weight, 22 parts by weight, 24 parts by weight, 26 parts by weight, 28 parts by weight, etc.

[0049] The vinyl silicone oil is 30-50 parts by weight, for example, 32 parts by weight, 34 parts by weight, 36 parts by weight, 38 parts by weight, 40 parts by weight, 42 parts by weight, 44 parts by weight, 46 parts by weight, 48 parts by weight, etc.

[0050] The hydrogen-containing silicone oil is 5-20 parts by weight, for example, 6 parts by weight, 8 parts by weight, 10 parts by weight, 12 parts by weight, 14 parts by weight, 16 parts by weight, 18 parts by weight, etc.

[0051] The hydrogen-containing silicone resin is 10-30 parts by weight, for example, 12 parts by weight, 14 parts by weight, 16 parts by weight, 18 parts by weight, 20 parts by weight, 22 parts by weight, 24 parts by weight, 26 parts by weight, 28 parts by weight, etc.

[0052] The catalyst is 0.01-0.5 parts by weight, for example, 0.05 parts by weight, 0.1 parts by weight, 0.15 parts by weight, 0.2 parts by weight, 0.25 parts by weight, 0.3 parts by weight, 0.35 parts by weight, 0.4 parts by weight, 0.45 parts by weight, etc.

[0053] The boron-containing organosilicon is 0.1-15 parts by weight, for example, it can be 0.5 parts by weight, 1 part by weight, 1.5 parts by weight, 2 parts by weight, 2.5 parts by weight, 3 parts by weight, 3.5 parts by weight, 4 parts by weight, 4.5 parts by weight, 5 parts by weight, 5.5 parts by weight, 6 parts by weight, 6.5 parts by weight, 7 parts by weight, 7.5 parts by weight, 8 parts by weight, 8.5 parts by weight, 9 parts by weight, 9.5 parts by weight, 10 parts by weight, 11 parts by weight, 12 parts by weight, 13 parts by weight, 14 parts by weight, etc.

[0054] Preferably, the vinyl silicone resin includes any one of vinyl MQ silicone resin, vinyl MDT silicone resin, vinyl MTQ silicone resin or vinyl DT silicone resin, or a combination of at least two thereof.

[0055] Preferably, the viscosity of the vinyl silicone resin at 25°C is 5000-50000 mPa·s, for example, it may be 5500 mPa·s, 6000 mPa·s, 6500 mPa·s, 7000 mPa·s, 7500 mPa·s, 8000 mPa·s, 8500 mPa·s, 9000 mPa·s, 9500 mPa·s, 10000 mPa·s, 15000 mPa·s, 20000 mPa·s, 25000 mPa·s, 30000 mPa·s, 35000 mPa·s, 40000 mPa·s, 45000 mPa·s, etc.

[0056] Preferably, the vinyl content of the vinyl silicone resin is 0.3-1.0 mmol / g, for example, it can be 0.35 mmol / g, 0.4 mmol / g, 0.45 mmol / g, 0.5 mmol / g, 0.55 mmol / g, 0.6 mmol / g, 0.65 mmol / g, 0.7 mmol / g, 0.75 mmol / g, 0.8 mmol / g, 0.85 mmol / g, 0.9 mmol / g, 0.95 mmol / g, etc.

[0057] Preferably, the vinyl silicone oil includes any one of silicone oil containing vinyl groups at the terminal, silicone oil containing vinyl groups at the side groups, and silicone oil containing vinyl groups at both the terminal and the side groups, or a combination of at least two of them.

[0058] Preferably, the viscosity of the vinyl silicone oil at 25° C. is 100-20000 mPa·s, for example, 500 mPa·s, 1000 mPa·s, 1500 mPa·s, 2000 mPa·s, 2500 mPa·s, 3000 mPa·s, 3500 mPa·s, 4000 mPa·s, 4500 mPa·s, 5000 mPa·s, 5500 mPa·s, 6000 mPa·s, 6500 mPa·s, 7000 mPa·s, 7500 mPa·s, 8000 mPa·s, 8500 mPa·s, 9000 mPa·s, 9500 mPa·s, 10000 mPa·s, 15000 mPa·s, 20000 mPa·s, etc.

[0059] Preferably, the vinyl content of the vinyl silicone oil is 0.1-0.75mmol / g, for example, it can be 0.15mmol / g, 0.2mmol / g, 0.25mmol / g, 0.3mmol / g, 0.35mmol / g, 0.4mmol / g, 0.45mmol / g, 0.5mmol / g, 0.55mmol / g, 0.6mmol / g, 0.65mmol / g, 0.7mmol / g, etc.

[0060] Preferably, the general formula of the hydrogen-containing silicone resin is (R 21 R 22 R 23 SiO 1 / 2 ) x (R 24 R 25 SiO 2 / 2 ) y (R 26 SiO 3 / 2 ) z ; Among them, R 21 , R 22 , R 23 , R 24 , R 25 , R 26 are each independently selected from any one of a hydrogen atom, a C1-C5 straight chain or branched chain alkyl group, and R 21 , R 22 , R 23 , R 24 , R 25 , R 26At least one of them is a hydrogen atom; x:y:z is the molar ratio of each link, and x:y:z=1:(0.2-0.3):(2-3), for example, it can be 1:0.21:2.1, 1:0.22:2.2, 1:0.23:2.3, 1:0.24:2.4, 1:0.25:2.5, 1:0.26:2.6, 1:0.27:2.7, 1:0.28:2.8, 1:0.29:2.9, etc.

[0061] Preferably, the viscosity of the hydrogenated silicone resin at 25° C. is 10,000-40,000 mPa·s, for example, 12,000 mPa·s, 14,000 mPa·s, 16,000 mPa·s, 18,000 mPa·s, 20,000 mPa·s, 22,000 mPa·s, 24,000 mPa·s, 26,000 mPa·s, 28,000 mPa·s, 30,000 mPa·s, 32,000 mPa·s, 34,000 mPa·s, 36,000 mPa·s, 38,000 mPa·s, etc.

[0062] Preferably, the silicon hydrogen content of the hydrogen-containing silicone resin is 0.1-1.2 mmol / g, for example, it can be 0.15 mmol / g, 0.2 mmol / g, 0.25 mmol / g, 0.3 mmol / g, 0.35 mmol / g, 0.4 mmol / g, 0.45 mmol / g, 0.5 mmol / g, 0.55 mmol / g, 0.6 mmol / g, 0.65 mmol / g, 0.7 mmol / g, 0.75 mmol / g, 0.8 mmol / g, 0.85 mmol / g, 0.9 mmol / g, 0.95 mmol / g, 1 mmol / g, 1.05 mmol / g, 1.1 mmol / g, 1.15 mmol / g, etc.

[0063] Preferably, the general formula of the hydrogen-containing silicone oil is (R 31 R 32 R 33 SiO 1 / 2 ) p (R 34 R 35 SiO 2 / 2 ) m (R 36 R 37 SiO 2 / 2 ) n ; Among them, R 31 , R 32 , R 33 , R 34 , R 35 , R 36 , R 37are each independently selected from any one of a hydrogen atom, a C1-C5 straight chain or branched chain alkyl group, and R 34 , R 35 , R 36 , R 37 At least one of them is a hydrogen atom; 1≤p≤2, 0≤m≤50 (for example, 2, 5, 8, 10, 12, 15, 20, 25, 30, 35, 40, 45, etc.), 0≤n≤50 (for example, 2, 5, 8, 10, 12, 15, 20, 25, 30, 35, 40, 45, etc.), and m and n are not 0 at the same time.

[0064] Preferably, the viscosity of the hydrogen-containing silicone oil at 25° C. is 100-3000 mPa·s, for example, 200 mPa·s, 400 mPa·s, 500 mPa·s, 600 mPa·s, 800 mPa·s, 1000 mPa·s, 1200 mPa·s, 1500 mPa·s, 1800 mPa·s, 2000 mPa·s, 2200 mPa·s, 2500 mPa·s, 2800 mPa·s, etc.

[0065] Preferably, the silicon hydrogen content of the hydrogen-containing silicone oil is 0.05-0.5 mmol / g, for example, it may be 0.1 mmol / g, 0.15 mmol / g, 0.2 mmol / g, 0.25 mmol / g, 0.3 mmol / g, 0.35 mmol / g, 0.4 mmol / g, 0.45 mmol / g, etc.

[0066] Preferably, in the raw materials for preparing the optical adhesive, the ratio of the total molar amount of vinyl groups to the total molar amount of silyl groups is (0.95-1.05):1, for example, it can be 0.96:1, 0.97:1, 0.98:1, 0.99:1, 1:1, 1.01:1, 1.02:1, 1.03:1, 1.04:1, etc.

[0067] Preferably, the catalyst comprises any one of chloroplatinic acid, Karstedt platinum catalyst or Willing platinum catalyst, or a combination of at least two thereof.

[0068] Preferably, the raw materials for preparing the optical adhesive also include 0.2-0.5 parts by weight of an inhibitor, for example, 0.22 parts by weight, 0.24 parts by weight, 0.26 parts by weight, 0.28 parts by weight, 0.3 parts by weight, 0.32 parts by weight, 0.34 parts by weight, 0.36 parts by weight, 0.38 parts by weight, 0.4 parts by weight, 0.42 parts by weight, 0.44 parts by weight, 0.46 parts by weight, 0.48 parts by weight, etc.

[0069] Preferably, the inhibitor comprises an alcohol compound containing an unsaturated group and / or a siloxane containing at least two vinyl groups.

[0070] Preferably, the alcohol compound containing an unsaturated group includes any one of the alcohol compounds containing a carbon-carbon triple bond.

[0071] Preferably, the inhibitor includes any one of 1,4-butynediol, ethynylcyclohexanol, tetramethyltetravinylcyclotetrasiloxane or 2-methyl-3-butyn-2-ol, or a combination of at least two thereof.

[0072] In a fifth aspect, the present invention provides an organosilicon OCA, comprising a first release film, an optical adhesive layer, and a second release film stacked in sequence; the optical adhesive layer is formed by curing the optical adhesive as described in the fourth aspect.

[0073] Preferably, the thickness of the optical adhesive layer is 50-500 μm, for example, 100 μm, 150 μm, 200 μm, 250 μm, 300 μm, 350 μm, 400 μm, 450 μm, etc.

[0074] Preferably, the first release film and the second release film are each independently selected from any one of a non-silicone release film and a fluorine release film.

[0075] Preferably, the thickness of the first release film and the second release film is independently 20-2000μm, for example, it can be 60μm, 70μm, 80μm, 90μm, 100μm, 110μm, 120μm, 130μm, 140μm, 150μm, 160μm, 170μm, 180μm, 190μm, 200μm, 400μm, 600μm, 800μm, 1000μm, 1200μm, 1400μm, 1600μm, 1800μm, etc.

[0076] Preferably, the release force between the first release film and the second release film differs by 15-20 gf / 25mm, for example, it may be 15.5 gf / 25mm, 16gf / 25mm, 16.5 gf / 25mm, 17gf / 25mm, 17.5 gf / 25mm, 18gf / 25mm, 18.5 gf / 25mm, 19gf / 25mm, 19.5 gf / 25mm, etc.

[0077] In a sixth aspect, the present invention provides a use of the optical adhesive as described in the fourth aspect or the silicone OCA as described in the fifth aspect in display bonding.

[0078] Compared with the prior art, the present invention has the following beneficial effects:

[0079] (1) The boron-containing organosilicon provided by the present invention has a more controllable structure and no by-products through the design of the raw materials for preparation, and can be used as a tackifier in optical adhesives. It has good compatibility with the organosilicon material in the optical adhesive and has an excellent tackifying effect on the optical adhesive, so that the organosilicon OCA can have good initial bonding performance with glass, ink, and polarizer at the same time, and can improve the low temperature resistance and high temperature and high humidity resistance of the organosilicon OCA;

[0080] (2) Using the organosilicon OCA containing boron organosilicon provided by the present invention, the initial peeling force for ink is 5.358-11.323 N / 25mm, and the peeling force after 5 minutes is 15.837-22.385 N / 25mm; the initial peeling force for glass is 5.354-11.997 N / 25mm, and the peeling force after 5 minutes is 15.625-22.315 N / 25mm; the initial peeling force for polarizer is 5.035-9.591 N / 25mm, and the peeling force after 5 minutes is 16.325-22.516 N / 25mm;

[0081] (3) The light transmittance of the organosilicon OCA using the boron-containing organosilicon provided by the present invention is 91.35-92.91%, the glass transition temperature is -50 to -40°C, the initial haze is 0.11-0.18%, the haze after aging at 105°C for 1000 hours is 0.10-0.17%, and the haze after aging at 85°C / 85%RH for 1000 hours is 0.26-0.29%. BRIEF DESCRIPTION OF THE DRAWINGS

[0082] Figure 1 is an infrared spectrum of the boron-containing organosilicon provided in Example 2;

[0083] Figure 2 This is the gel permeation chromatogram of the boron-containing organosilicon provided in Example 2. DETAILED DESCRIPTION

[0084] The technical solution of the present invention is further described below in conjunction with the accompanying drawings and through specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0085] Example 1

[0086] A boron-containing organosilicon, wherein the raw materials for preparing the boron-containing organosilicon include dimethylsilanediol, methyltrimethoxysilane, dimethyldimethoxysilane, boric acid and cyclohexanone;

[0087] The preparation method of the boron-containing organosilicon comprises:

[0088] A dry round-bottom flask equipped with a mechanical stirrer, a thermometer, and a vacuum device is placed in an oil bath, and 161.30 g of dimethylsilanediol, 46.37 g of boric acid, 102.17 g of methyltrimethoxysilane, 210.38 g of dimethyldimethoxysilane, and 173 g of cyclohexanone are added to the round-bottom flask, wherein the molar ratio of hydroxyl to alkoxy in the reaction system is 1:1, and the molar ratio of element B to element Si is 1:5.7; after the materials are uniformly stirred by mechanical stirring at room temperature, the oil bath is heated to 100°C and reacted for 4 hours, and then the oil temperature is raised to 160°C, and the solvent is distilled off under reduced pressure to obtain a colorless and transparent liquid product with a yield of 74%. There is no abnormality after being placed at room temperature for 2 months.

[0089] Example 2

[0090] A boron-containing organosilicon, wherein the raw materials for preparing the boron-containing organosilicon include dimethylsilanediol, methyltrimethoxysilane, dimethyldimethoxysilane, boric acid and cyclohexanone;

[0091] The preparation method of the boron-containing organosilicon comprises:

[0092] A dry round-bottom flask equipped with a mechanical stirrer, a thermometer, and a vacuum device is placed in an oil bath, 161.30 g of dimethylsilanediol, 38.64 g of boric acid, 102.17 g of methyltrimethoxysilane, 210.38 g of dimethyldimethoxysilane, and 170 g of cyclohexanone are added to the round-bottom flask, the molar ratio of hydroxyl to alkoxy in the reaction system is 0.93:1, and the molar ratio of element B to element Si is 1:6.8; after the materials are uniformly stirred by mechanical stirring at room temperature, the oil bath is heated to 100°C, the reaction is carried out for 4 hours, and the oil temperature is subsequently raised to 160°C, and the solvent is removed by reduced pressure distillation to obtain a colorless and transparent liquid product with a yield of 85%. There is no abnormality after being placed at room temperature for 2 months;

[0093] The boron-containing organosilicon was tested using a German Bruker Fourier infrared spectrometer (model: ALPHA). The test results are as follows: Figure 1 As shown in the infrared spectrum of boron-containing organosilicon provided in Example 2, Figure 1 It can be seen at 1340cm -1 There is an obvious Si-OB characteristic peak at

[0094] The sample was prepared with tetrahydrofuran as the mobile phase (concentration of 0.02 g / mL), injection volume of 10 μL, flow rate of 1 mL / min, and polystyrene as the standard sample. The standard curve was tested at 40°C using a Waters 2414 differential refractometer. The test results are shown in Figure 2 As shown in the gel permeation chromatogram of boron-containing organosilicon provided in Example 2, Figure 2It can be seen that the boron-containing organosilicon synthesized in Example 2 has a number average molecular weight of 18721 and a dispersion coefficient of 1.36.

[0095] Example 3

[0096] A boron-containing organosilicon, wherein the raw materials for preparing the boron-containing organosilicon include dimethylsilanediol, methyltrimethoxysilane, dimethyldimethoxysilane, boric acid and cyclohexanone;

[0097] The preparation method of the boron-containing organosilicon comprises:

[0098] A dry round-bottom flask equipped with a mechanical stirrer, a thermometer, and a vacuum device is placed in an oil bath, and 161.30 g of dimethylsilanediol, 35.55 g of boric acid, 95.35 g of methyltrimethoxysilane, 210.38 g of dimethyldimethoxysilane, and 167 g of cyclohexanone are added to the round-bottom flask, wherein the molar ratio of hydroxyl to alkoxy in the reaction system is 0.93:1, and the molar ratio of element B to element Si is 1:7.3; after the materials are uniformly stirred by mechanical stirring at room temperature, the oil bath is heated to 100°C and reacted for 4 hours, and then the oil temperature is raised to 160°C, and the solvent is distilled off under reduced pressure to obtain a colorless and transparent liquid product with a yield of 87%. There is no abnormality after being placed at room temperature for 2 months.

[0099] Example 4

[0100] A boron-containing organosilicon, wherein the raw materials for preparing the boron-containing organosilicon include dimethylsilanediol, methyltrimethoxysilane, dimethyldimethoxysilane, boric acid and cyclohexanone;

[0101] The preparation method of the boron-containing organosilicon comprises:

[0102] A dry round-bottom flask equipped with a mechanical stirrer, a thermometer, and a vacuum device is placed in an oil bath, and 161.30 g of dimethylsilanediol, 30.91 g of boric acid, 85.14 g of methyltrimethoxysilane, 210.38 g of dimethyldimethoxysilane, and 162 g of cyclohexanone are added to the round-bottom flask, wherein the molar ratio of hydroxyl to alkoxy in the reaction system is 0.93:1, and the molar ratio of element B to element Si is 1:8.25; after the materials are uniformly stirred by mechanical stirring at room temperature, the oil bath is heated to 100°C and reacted for 4 hours, and then the oil temperature is raised to 160°C, and the solvent is distilled off under reduced pressure to obtain a colorless and transparent liquid product with a yield of 87%. There is no abnormality after being placed at room temperature for 2 months.

[0103] Example 5

[0104] A boron-containing organosilicon, wherein the raw materials for preparing the boron-containing organosilicon include dimethylsilanediol, methyltrimethoxysilane, dimethyldimethoxysilane, boric acid and cyclohexanone;

[0105] The preparation method of the boron-containing organosilicon comprises:

[0106] A dry round-bottom flask equipped with a mechanical stirrer, a thermometer, and a vacuum device is placed in an oil bath, and 161.30 g of dimethylsilanediol, 27.82 g of boric acid, 102.17 g of methyltrimethoxysilane, 210.38 g of dimethyldimethoxysilane, and 167 g of cyclohexanone are added to the round-bottom flask, wherein the molar ratio of hydroxyl to alkoxy in the reaction system is 0.84:1, and the molar ratio of element B to element Si is 1:9.4; after the materials are uniformly stirred by mechanical stirring at room temperature, the oil bath is heated to 100°C and reacted for 4 hours, and then the oil temperature is raised to 160°C, and the solvent is distilled off under reduced pressure to obtain a colorless and transparent liquid product with a yield of 80%. There is no abnormality after being placed at room temperature for 2 months.

[0107] Example 6

[0108] A boron-containing organosilicon, wherein the raw materials for preparing the boron-containing organosilicon include dimethylsilanediol, methyltrimethoxysilane, dimethyldimethoxysilane, boric acid and cyclohexanone;

[0109] The preparation method of the boron-containing organosilicon comprises:

[0110] A dry round-bottom flask equipped with a mechanical stirrer, a thermometer, and a vacuum device is placed in an oil bath, and 161.30 g of dimethylsilanediol, 23.19 g of boric acid, 102.17 g of methyltrimethoxysilane, 210.38 g of dimethyldimethoxysilane, and 140 g of cyclohexanone are added to the round-bottom flask, wherein the molar ratio of hydroxyl to alkoxy in the reaction system is 0.8:1, and the molar ratio of element B to element Si is 1:11.3; after the materials are uniformly stirred by mechanical stirring at room temperature, the oil bath is heated to 100°C and reacted for 4 hours, and then the oil temperature is raised to 160°C, and the solvent is distilled off under reduced pressure to obtain a colorless and transparent liquid product with a yield of 72%. There is no abnormality after being placed at room temperature for 2 months.

[0111] Comparative Example 1

[0112] A boron-containing organosilicon, wherein the raw materials for preparing the boron-containing organosilicon include dimethylsilanediol, methyltrimethoxysilane, dimethyldimethoxysilane, boric acid and cyclohexanone;

[0113] The preparation method of the boron-containing organosilicon comprises:

[0114] A dry round-bottom flask equipped with a mechanical stirrer, a thermometer, and a vacuum device is placed in an oil bath, and 179.73 g of dimethylsilanediol, 46.37 g of boric acid, 102.17 g of methyltrimethoxysilane, 185.14 g of dimethyldimethoxysilane, and 150 g of cyclohexanone are added to the round-bottom flask, wherein the molar ratio of hydroxyl to alkoxy in the reaction system is 1.15:1, and the molar ratio of element B to element Si is 1:5.7; after the materials are uniformly stirred by mechanical stirring at room temperature, the oil bath is heated to 100°C and reacted for 4 hours, and then the oil temperature is raised to 160°C, and the solvent is distilled off under reduced pressure to obtain a colorless and transparent liquid product with a yield of 67%. There is no abnormality after being placed at room temperature for 2 months.

[0115] Comparative Example 2

[0116] A boron-containing organosilicon, wherein the raw materials for preparing the boron-containing organosilicon include dimethylsilanediol, methyltrimethoxysilane, dimethyldimethoxysilane, boric acid and cyclohexanone;

[0117] The preparation method of the boron-containing organosilicon comprises:

[0118] A dry round-bottom flask equipped with a mechanical stirrer, a thermometer, and a vacuum device is placed in an oil bath, and 211.07 g of dimethylsilanediol, 24.11 g of boric acid, 102.17 g of methyltrimethoxysilane, 210.38 g of dimethyldimethoxysilane, and 160 g of cyclohexanone are added to the round-bottom flask, wherein the molar ratio of hydroxyl to alkoxy in the reaction system is 1:1, and the molar ratio of element B to element Si is 1:12.3; after the materials are uniformly stirred by mechanical stirring at room temperature, the oil bath is heated to 100°C and reacted for 4 hours, and then the oil temperature is raised to 160°C, and the solvent is distilled off under reduced pressure to obtain a colorless and transparent liquid product with a yield of 75%. There is no abnormality after being placed at room temperature for 2 months.

[0119] Comparative Example 3

[0120] A boron-containing organosilicon, wherein the raw materials for preparing the boron-containing organosilicon include dimethylsilanediol, methyltrimethoxysilane, dimethyldimethoxysilane, boric acid and cyclohexanone;

[0121] The preparation method of the boron-containing organosilicon comprises:

[0122] A dry round-bottom flask equipped with a mechanical stirrer, a thermometer, and a vacuum device is placed in an oil bath, and 161.30 g of dimethylsilanediol, 71.10 g of boric acid, 238.39 g of methyltrimethoxysilane, 90.16 g of dimethyldimethoxysilane, and 187 g of cyclohexanone are added to the round-bottom flask, wherein the molar ratio of hydroxyl to alkoxy in the reaction system is 1.03:1, and the molar ratio of element B to element Si is 1:3.7; after the materials are uniformly stirred by mechanical stirring at room temperature, the oil bath is heated to 100°C and reacted for 4 hours, and then the oil temperature is raised to 160°C, and the solvent is distilled off under reduced pressure to obtain a colorless and transparent liquid product with a yield of 67%. There is no abnormality after being placed at room temperature for 2 months.

[0123] Comparative Example 4

[0124] A boron-containing organosilicon, wherein the raw materials for preparing the boron-containing organosilicon include dimethylsilanediol, methyltrimethoxysilane, dimethyldimethoxysilane, boric acid and cyclohexanone;

[0125] The preparation method of the boron-containing organosilicon comprises:

[0126] A dry round-bottom flask equipped with a mechanical stirrer, a thermometer, and a vacuum device is placed in an oil bath, and 161.30 g of dimethylsilanediol, 35.55 g of boric acid, 272.44 g of methyltrimethoxysilane, 54.10 g of dimethyldimethoxysilane, and 174 g of cyclohexanone are added to the round-bottom flask, wherein the molar ratio of hydroxyl to alkoxy in the reaction system is 0.76:1, and the molar ratio of element B to element Si is 1:7.3; after the materials are uniformly stirred by mechanical stirring at room temperature, the oil bath is heated to 100°C and reacted for 4 hours, and then the oil temperature is raised to 160°C, and the solvent is distilled off under reduced pressure to obtain a colorless and transparent liquid product with a yield of 64%. After being placed at room temperature for 2 weeks, fogging occurs, which cannot meet the optical performance requirements of the optical adhesive.

[0127] Comparative Example 5

[0128] A boron-containing organosilicon, wherein the raw materials for preparing the boron-containing organosilicon include neopentyl glycol, methyltrimethoxysilane, dimethyldimethoxysilane, boric acid and cyclohexanone;

[0129] The preparation method of the boron-containing organosilicon comprises:

[0130] A dry round-bottom flask equipped with a mechanical stirrer, a thermometer, and a vacuum device is placed in an oil bath, and 222.50 g of neopentyl glycol, 22.73 g of boric acid, 102.17 g of methyltrimethoxysilane, 210.38 g of dimethyldimethoxysilane, and 178 g of cyclohexanone are added to the round-bottom flask, wherein the molar ratio of hydroxyl to alkoxy in the reaction system is 0.93:1, and the molar ratio of element B to element Si is 1:6.8; after the materials are uniformly stirred by mechanical stirring at room temperature, the oil bath is heated to 100°C, the reaction is carried out for 4 hours, and then the oil temperature is raised to 160°C, and the solvent is removed by reduced pressure distillation to obtain a colorless and transparent liquid product with a yield of 65%. There is no abnormality after being placed for 2 months.

[0131] The preparation method of the boron-containing organosilicon provided by the present invention is simple, does not require the addition of a catalyst, and is colorless and transparent. After storage for 2 months, there is no adverse phenomenon such as fogging and precipitation, and the yield is 72-87%. In Comparative Example 4, since the molar ratio of hydroxyl to alkoxy in the reaction system is 0.76:1, although colorless and transparent boron-containing organosilicon can be obtained, the residual alkoxy absorbs moisture in the air and undergoes a hydrolysis reaction, resulting in the boron-containing organosilicon being fogged and turbid after storage for 14 days, and having poor storage stability, and cannot be applied to optical adhesives; Comparative Example 5 uses fatty alcohols to replace silanols, and the compatibility of fatty alcohols with siloxane monomers and boric acid compounds is poor. After addition, the reactor becomes turbid and foggy, the degree of reaction is low, and the product yield is only 65%.

[0132] The sources of the raw materials and equipment used in the following application examples and comparative examples are as follows:

[0133] (A) Vinyl silicone oil

[0134]

[0135] (B) Vinyl silicone resin

[0136] Code supplier model Viscosity (mPa·s) Vinyl content (mmol / g) B-1 Delta Silicone DT-10050 10000 0.4444

[0137] (C) Hydrogenated silicone oil

[0138] Code Manufacturer Brand Silicon hydride content (mmol / g) C-1 Anhui Iyota Silicone Oil Co., Ltd. IOTA203 0.18

[0139] (D) Hydrogenated silicone resin

[0140] The general formula is: (HMe2SiO 1 / 2 ) x (HMeSiO 2 / 2 ) y (MeSiO 3 / 2 ) z , wherein Me is methyl.

[0141]

[0142] (E) Catalyst

[0143] Code supplier model E-1 Anhui Iyota Silicone Oil Co., Ltd. IOTAPC16

[0144] (F) Inhibitors

[0145] Code supplier model F-1 Guangzhou Xiyi Chemical CEY

[0146] Coating equipment

[0147] Code Manufacturer model Coating Machine Shangwang Printing Machinery Co., Ltd. THVG-1100

[0148] Application Example 1

[0149] An optical adhesive, wherein the raw materials for preparing the optical adhesive include 127 parts by weight of vinyl silicone resin B, 140 parts by weight of vinyl silicone oil A, 15 parts by weight of hydrogen-containing silicone oil C, 123 parts by weight of hydrogen-containing silicone resin D, 4.4 parts by weight of boron-containing organosilicon provided in Example 1, 10.1 parts by weight of catalyst E, and 10.5 parts by weight of inhibitor F;

[0150] The preparation method of the optical adhesive comprises:

[0151] Vinyl silicone resin B-1, vinyl silicone oil A-1, hydrogenated silicone oil C-1, hydrogenated silicone resin D-1, boron-containing organosilicon provided in Example 1, catalyst E-1 and inhibitor F-1 are mixed, stirred evenly, and vacuum degassed to obtain the optical adhesive;

[0152] The optical adhesive is used for preparing the organosilicon OCA, and the specific method is as follows:

[0153] The optical adhesive is coated on a non-silicone release film (thickness of 75 μm, release force of 30 gf / 25 mm) by blade coating, with a coating thickness of 250 μm, and then thermally cured (curing conditions are 60° C., 10 min), and then a fluorine release film (thickness of 50 μm, release force of 13 gf / 25 mm) is attached to the side of the obtained optical adhesive layer away from the non-silicone release film to obtain the silicone OCA.

[0154] Application Examples 2-6, Application Comparative Examples 1-3

[0155] An optical adhesive and a preparation method thereof, which differs from Application Example 1 only in that the boron-containing organosilicon provided in Example 1 is replaced by the boron-containing organosilicon provided in Examples 2-6 and Comparative Examples 1-3 in equal amounts, and the remaining raw materials, process parameters and steps are the same as those in Application Example 1;

[0156] The optical adhesive is used for preparing an organosilicon OCA, and the preparation method of the organosilicon OCA is the same as that of Application Example 1.

[0157] Application Comparative Example 4

[0158] An optical adhesive and a preparation method thereof, which differs from Application Example 1 only in that the boron-containing organosilicon provided in Example 1 is replaced by an equal amount of silane coupling agent KH-560, and the remaining raw materials, process parameters and steps are the same as those in Application Example 1;

[0159] The optical adhesive is used for preparing an organosilicon OCA, and the preparation method of the organosilicon OCA is the same as that of Application Example 1.

[0160] Application Comparative Example 5

[0161] An optical adhesive and a preparation method thereof, which differs from Application Example 1 only in that an equal amount of the boron-containing silicone provided in Example 1 is replaced by an equal amount of the boron-containing silicone provided in Comparative Example 5, and the remaining raw materials, process parameters and steps are the same as those in Application Example 1; since the refractive index of the boron-containing silicone provided in Comparative Example 5 is significantly different from that of the silicone polymer, severe fogging occurs during the preparation of the optical adhesive, which does not meet the requirements of the optical adhesive.

[0162] Performance Testing

[0163] (1) Peeling force test: One side of the optical adhesive layer of the organic silicon OCA provided in the application example and the comparative application example is attached to the substrate, and the other side is attached to the PET original film (purchased from Hefei Lucky Technology, with a thickness of 100 μm) to form a combined structure of PET-organic silicon OCA-substrate, which is placed on an electric roller machine (Beidou Instrument, PT-509) and rolled once with a 3 kg roller at a speed of 10 mm / s to obtain a peeling sample of the corresponding substrate; after the sample is prepared, wait for 0 min, 3 min, and 5 min respectively, and test the 180° peeling force at different placement times according to GB / T2792-2014;

[0164] (2) Light transmittance and haze test: Tested in accordance with GB / T 24107.1;

[0165] (3) Glass transition temperature: tested by Hitachi DSC200;

[0166] The organic silicon OCA provided by Application Examples 1-6 and Comparative Application Examples 1-4 was tested according to the above method, and the test results are shown in Tables 1 and 2 below:

[0167] Table 1

[0168]

[0169] Table 2

[0170]

[0171] It can be seen from the test data in the table that controlling the molar ratio of B to Si in the preparation raw material of boron-containing organosilicon within the range of 1:(5-11.5) can make the organosilicon OCA have good bonding effect on substrates such as ink, glass, polarizer, etc., and excellent hydrolysis resistance. Compared with the silane coupling agent commonly used as a tackifier for organosilicon OCA, the organosilicon OCA provided in Application Examples 1-6 has improved bonding performance to ink, glass, and polarizer substrates to varying degrees, and the initial peeling force is greater than 2N / 25mm, and the peeling force increases rapidly, and can basically reach the final value in 5min. The final peeling force for ink, glass, and polarizer can reach up to about 22N / 25mm at most, and the haze changes little after double 85 aging, and the high temperature and humidity resistance is excellent.

[0172] The molar ratio of B to Si in the preparation raw materials of the boron-containing organosilicon used in Application Examples 2-6 is in the range of 1:(6.5-11.5), and the improvement effect of organosilicon OCA on the bonding performance of ink, glass, and polarizer substrates is particularly prominent. Application Comparative Example 4 uses KH-560 as a tackifier. The peeling force of the organosilicon OCA increases slowly after lamination. The peeling force of the polarizer can only reach the final peeling force of 2.44N / 25mm after 96h. The peeling force of the glass and ink both need to be placed for 48h to reach the final peeling force, which are 13.8N / 25mm and 3.57N / 25mm, respectively. In addition, the glass transition temperature of the organosilicon OCA provided by the present invention is below -40°C, and it has excellent low temperature resistance, which can meet the use requirements of different scenarios.

[0173] The molar ratio of hydroxyl to alkoxy in the preparation raw material of the boron-containing organosilicon used in Comparative Example 1 is 1.15:1. The OH content in the preparation raw material of the boron-containing organosilicon is too high, which increases the possibility of boric acid being exposed at the end. The boron-containing organosilicon is easily attacked by water vapor and fogs. The hydrolysis resistance of silicone OCA is poor, and it will absorb water vapor in the air and cause the film to fog.

[0174] The molar ratios of B to Si in the preparation raw materials of the boron-containing organosilicon used in Application Comparative Example 2 and Application Comparative Example 3 are 1:12.3 and 1:3.7, respectively. If the B content in the preparation raw materials of the boron-containing organosilicon is too low, the bonding performance will obviously deteriorate. If the B content is too high, the hydrolysis resistance of the organosilicon OCA will be poor, and it will absorb water vapor in the air to cause the film to fog.

[0175] The applicant declares that the present invention illustrates the boron-containing organosilicon, optical adhesive, organosilicon OCA and its preparation method and application through the above-mentioned embodiments and application examples, but the present invention is not limited to the above-mentioned embodiments and application examples, that is, it does not mean that the present invention must rely on the above-mentioned embodiments and application examples to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of various raw materials of the product of the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A boron-containing organosilicon, characterized in that: The raw materials for preparing the boron-containing organosilicon include a combination of silanol, siloxane monomer and boric acid compound; In the raw material for preparing the boron-containing organosilicon, the ratio of the total molar amount of hydroxyl groups to the total molar amount of alkoxy groups is (0.8-1.1):1, and the ratio of the total molar amount of B elements to the total molar amount of Si elements is 1:(5-11.5).

2. The boron-containing organosilicon according to claim 1, characterized in that: The general formula of the silanol is R 11 4-a Si(OH) a ; Among them, R 11 Each is independently selected from any one of C1-C5 straight or branched alkyl, C3-C8 cyclic hydrocarbon group; a is 2 or 3; Preferably, the silanol comprises any one or a combination of at least two of dimethylsilanediol, methylethylsilanediol, methylphenylsilanediol, methylsilanetriol or phenylsilanetriol; Preferably, the general formula of the siloxane monomer is R 12 4-b Si(OR 13 ) b ; Among them, R 12 Each is independently selected from any one of a C2-C6 unsaturated hydrocarbon group, a C1-C5 straight chain or branched alkyl group; R 13 Each independently selected from any one of C1-C5 straight or branched alkyl groups; b is an integer selected from 1 to 3, more preferably 2 or 3; Preferably, the siloxane monomer comprises a first siloxane monomer, a second siloxane monomer and optionally a third siloxane monomer; The general formula of the first siloxane monomer is R A1 2Si(OR A2 )2; The general formula of the second siloxane monomer is R B1 Si(OR B2 )3; The third siloxane monomer has the general formula R C1 3SiOR C2 ; Among them, R A1 , R B1 , R C1 Each is independently selected from any one of a C2-C6 unsaturated hydrocarbon group, a C1-C5 straight chain or branched alkyl group; R A2 , R B2 , R C2 Each independently selected from any one of C1-C5 straight or branched alkyl groups; Preferably, the first siloxane monomer includes any one or a combination of at least two of methylvinyldimethoxysilane, dimethyldimethoxysilane or dimethyldiethoxysilane; Preferably, the second siloxane monomer comprises methyltrimethoxysilane and / or methyltriethoxysilane; Preferably, the third siloxane monomer comprises trimethylmethoxysilane; Preferably, the boric acid compound includes any one of boric acid, phenylboric acid or tetrahydroxyboron or a combination of at least two thereof; Preferably, the molar ratio of the hydroxyl group in the boric acid compound to the hydroxyl group in the silanol is 1:(1-7); Preferably, in the raw material for preparing the boron-containing organosilicon, the ratio of the total molar amount of the B element to the total molar amount of the Si element is 1:(6.5-11.5), and more preferably 1:(7-8.5).

3. The boron-containing organosilicon according to claim 1 or 2, characterized in that: The raw materials for preparing the boron-containing organosilicon also include a solvent; Preferably, the solvent comprises any one or a combination of at least two of N,N-dimethylformamide, dimethyl sulfoxide, methanol, acetonitrile, isopropanol, 1,4-dioxane or cyclohexanone; Preferably, based on the total mass of the silanol, siloxane monomer and boric acid compound being 100%, the mass of the solvent is 25-40%.

4. A method for preparing boron-containing organosilicon according to any one of claims 1 to 3, characterized in that: The preparation method comprises: Reaction of silanol and siloxane monomers with boric acid compounds to obtain the boron-containing organosilicon; Preferably, the reaction temperature is 80-140°C; Preferably, the reaction time is 3-7h; Preferably, the reaction is carried out in the presence of a solvent; Preferably, the reaction further comprises a step of reduced pressure distillation after completion.

5. A use of the boron-containing organosilicon according to any one of claims 1 to 3, characterized in that: The boron-containing organosilicon is used as a tackifier in optical adhesives.

6. An optical adhesive, characterized in that: In parts by weight, the raw materials for preparing the optical adhesive include:

7. The optical adhesive according to claim 6, characterized in that: The vinyl silicone resin includes any one of vinyl MQ silicone resin, vinyl MDT silicone resin, vinyl MTQ silicone resin or vinyl DT silicone resin, or a combination of at least two thereof; Preferably, the viscosity of the vinyl silicone resin at 25° C. is 5000-50000 mPa·s; Preferably, the vinyl content of the vinyl silicone resin is 0.3-1.0 mmol / g; Preferably, the vinyl silicone oil includes any one or a combination of at least two of silicone oil containing vinyl groups at the terminal, silicone oil containing vinyl groups at the side groups, and silicone oil containing vinyl groups at both the terminal and the side groups; Preferably, the viscosity of the vinyl silicone oil at 25° C. is 100-20000 mPa·s; Preferably, the vinyl content of the vinyl silicone oil is 0.1-0.75 mmol / g; Preferably, the general formula of the hydrogen-containing silicone resin is (R 21 R 22 R 23 SiO 1 / 2 ) x (R 24 R 25 SiO 2 / 2 ) y (R 26 SiO 3 / 2 ) z ; Among them, R 21 , R 22 , R 23 , R 24 , R 25 , R 26 are each independently selected from any one of a hydrogen atom, a C1-C5 straight chain or branched chain alkyl group, and R 21 , R 22 , R 23 , R 24 , R 25 , R 26 At least one of them is a hydrogen atom; x:y:z=1:(0.2-0.3):(2-3); Preferably, the viscosity of the hydrogenated silicone resin at 25° C. is 10000-40000 mPa·s; Preferably, the silicon hydrogen content of the hydrogen-containing silicone resin is 0.1-1.2 mmol / g; Preferably, the general formula of the hydrogen-containing silicone oil is (R 31 R 32 R 33 SiO 1 / 2 ) p (R 34 R 35 SiO 2 / 2 ) m (R 36 R 37 SiO 2 / 2 ) n ; Among them, R 31 , R 32 , R 33 , R 34 , R 35 , R 36 , R 37 are each independently selected from any one of a hydrogen atom, a C1-C5 straight chain or branched chain alkyl group, and R 34 , R 35 , R 36 , R 37 At least one of them is a hydrogen atom; 1≤p≤2, 0≤m≤50, 0≤n≤50, and m and n are not 0 at the same time; Preferably, the viscosity of the hydrogen-containing silicone oil at 25° C. is 100-3000 mPa·s; Preferably, the silicon hydrogen content of the hydrogen-containing silicone oil is 0.05-0.5 mmol / g; Preferably, in the raw materials for preparing the optical adhesive, the ratio of the total molar amount of vinyl groups to the total molar amount of silane groups is (0.95-1.05):

1.

8. The optical adhesive according to claim 6 or 7, characterized in that: The catalyst comprises any one or a combination of at least two of chloroplatinic acid, Karstedt platinum catalyst or Willing platinum catalyst; Preferably, the raw materials for preparing the optical adhesive further include 0.2-0.5 parts by weight of an inhibitor; Preferably, the inhibitor comprises an alcohol compound containing an unsaturated group and / or a siloxane containing at least two vinyl groups; Preferably, the inhibitor includes any one of 1,4-butynediol, ethynylcyclohexanol, tetramethyltetravinylcyclotetrasiloxane or 2-methyl-3-butyn-2-ol, or a combination of at least two thereof.

9. An organosilicon OCA, characterized in that: The organic silicon OCA comprises a first release film, an optical adhesive layer, and a second release film which are stacked in sequence; the optical adhesive layer is formed by curing the optical adhesive according to any one of claims 6 to 8; Preferably, the thickness of the optical adhesive layer is 20-2000 μm; Preferably, the thickness of the first release film and the second release film is independently 50-200 μm; Preferably, the release force difference between the first release film and the second release film is 15-20 gf / 25 mm.

10. Use of the optical adhesive according to any one of claims 6 to 8 or the organic silicon OCA according to claim 9 in display bonding.

Images