TW202037615A - Ultraviolet-curable pressure-sensitive silicone adhesive composition and cured object obtained therefrom - Google Patents

Abstract

An ultraviolet-curable pressure-sensitive silicone adhesive composition which comprises (A) an organopolysiloxane of formula (1) (R1 represents a polymerizable group or a monovalent hydrocarbon group and at least one of the R1 moieties is a polymerizable group, R2 represents an oxygen atom or an alkylene group, and m and n indicate numbers satisfying m ≥ 0, n ≥ 1, and 1 ≤ (m+n) ≤ 1,000), (B) an organopolysiloxane resin comprising (a) R3 3SiO1/2 units (R3 represents a monovalent hydrocarbon group) and (b) SiO4/2 units, the molar ratio of the (a) units to the (b) units being (0.6-1.2):1, (C) a compound having at least one group of formula (2) in the molecule (R4 represents a hydrogen atom or a methyl group, R5 represents a hydrogen atom or a monovalent hydrocarbon group, a is an integer of 1-5, and * indicates the site of bonding to an adjoining atom), and (D) a photopolymerization initiator. The ultraviolet-curable pressure-sensitive silicone adhesive composition has satisfactory curability and gives cured objects which, as temporary fixers, have excellent tackiness and strength.

Description

Ultraviolet curing type silicone adhesive composition and its cured product

The present invention relates to an ultraviolet-curable silicone adhesive composition and its cured product, and more specifically, to an ultraviolet-curable silicone adhesive composition that can be suitably used as a temporary fixing material for transferring objects And its hardened material.

In recent years, electronic devices represented by smart phones, liquid crystal displays, and automotive parts have not only been required to improve performance, but also to save space and energy. In response to such social needs, the electrical and electronic components mounted on it have also been miniaturized, and the assembly steps have also become more complicated and difficult every year.

In recent years, the development of a technology capable of selectively and one-time transfer of such miniaturized components or parts has attracted attention (Non-Patent Document 1). This technology is called Micro-Transfer Printing, which uses the adhesive force of the elastic body to pick up fine parts at a time and transfer them to the desired place with stronger adhesive force.

As a micro-transfer material, an adhesive article obtained by applying a silicone adhesive composition to a base material by spin coating, screen printing, etc., and then curing it is used.

As an adhesive material used for this purpose, silicone elastomer is known, and a number of heat-curing solvent-free silicone adhesives have been proposed (Patent Documents 1 to 3). However, the heat-curing type requires a lot of energy, and it needs to be cooled to room temperature after heat-curing, and there is a problem of time-consuming steps.

Although there has been development of silicone resins that can be cured in a short time at room temperature by ultraviolet radiation, this group of materials only has the adhesive force of the silicone material itself (Patent Document 4). However, there are components or parts that cannot be transferred by the inherently small adhesion of polysilicone elastomers, and UV-curing silicone adhesives with stronger adhesion are expected. [Prior Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent No. 5825738 [Patent Document 2] Japanese Patent No. 2631098 [Patent Document 3] Japanese Patent No. 5234064 [Patent Document 4] Japanese Patent No. 5989417 [Non-Patent Literature]

[Non-Patent Document 1] JOHN A. ROGERS, "Transfer printing by kinetic control of adhesion to an elastometric stamp", nature materials, Nature Publishing Group, December 11, 2007, Vol. 6, p.33-38

[The problem to be solved by the invention]

The present invention was made in view of the above circumstances, and its object is to provide an ultraviolet-curable silicone adhesive composition and a cured product thereof. The ultraviolet-curable silicone adhesive composition has good curing properties and provides excellent temporary fixation materials. The adhesiveness and strength of the hardened material. [Means to solve the problem]

The inventors of the present invention conducted diligent reviews to achieve the above-mentioned objects and found that by using specific organopolysiloxanes having (meth)acryloxy group-containing groups, prescribed organopolysiloxane resins, (Meth)acrylamide-based compound, photoinitiator, and rapid curing by ultraviolet radiation, can obtain ultraviolet curing type with stronger adhesive force than silicone elastomer originally possessed The silicone adhesive composition has completed the present invention.

(式中，R¹ 彼此獨立地表示選自丙烯醯氧基烷基、甲基丙烯醯氧基烷基、丙烯醯氧基烷氧基及甲基丙烯醯氧基烷氧基中的聚合性基、或碳原子數1～20的一價烴基，R¹ 中至少1個為前述聚合性基， R² 彼此獨立地表示氧原子或碳原子數1～20的伸烷基， m及n表示滿足m≧0，n≧1，1≦m+n≦1,000之數。) (B)包含(a)R³ ₃ SiO_1/2 單位(式中，R³ 表示碳原子數1～10的一價烴基。)與(b)SiO_4/2 單位，且(a)單位與(b)單位的莫耳比為0.6～1.2：1的範圍之有機聚矽氧烷樹脂：1～1,000質量份， (C)1分子中具有至少1個下述式(2)所表示的基之(甲基)丙烯醯胺化合物：1～500質量份，及

(式中，R⁴ 表示氫原子或甲基，R⁵ 表示氫原子或碳數1～12的一價烴基，a表示1～5的整數，星號(＊)表示與相鄰原子的鍵結部位。) (D)光聚合起始劑：0.01～20質量份， 2.　一種硬化物，其係如1之紫外線硬化型矽氧黏著劑組成物之硬化物， 3.　一種黏著劑，其包含如2之硬化物， 4.　一種黏著片，其包含如2之硬化物， 5.　一種微構造體轉印用印模，其包含如2之硬化物， 6.　如5之微構造體轉印用印模，其具有至少1個凸狀構造， 7.　一種微構造體轉印裝置，其具有如5或6之微構造體轉印用印模， 8. 　一種微構造體保持基板，其具有包含如2之硬化物之黏著劑層， 9.　一種微構造體轉印裝置，其具有如8之微構造體保持基板。 [發明的效果]That is, the present invention provides: 1. An ultraviolet curable silicone adhesive composition characterized by containing: (A) Organopolysiloxane represented by the following general formula (1): 100 parts by mass,

(In the formula, R ¹ independently represents a polymerizable group selected from the group consisting of acryloxyalkyl, methacryloxyalkyl, acryloxyalkoxy, and methacryloxyalkoxy. , Or a monovalent hydrocarbon group with 1 to 20 carbon atoms, at least one of R ¹ is the aforementioned polymerizable group, R ² independently represents an oxygen atom or an alkylene group with 1 to 20 carbon atoms, m and n represent m≧0, n≧1, 1≦m+n≦1,000.) (B) includes (a) R ³ ₃ SiO _1/2 unit (where R ³ represents a monovalent carbon atom number of 1-10 Hydrocarbyl group.) and (b) SiO _4/2 unit, and the molar ratio of (a) unit to (b) unit is in the range of 0.6 to 1.2:1 organopolysiloxane resin: 1 to 1,000 parts by mass, ( C) A (meth)acrylamide compound having at least one group represented by the following formula (2) in one molecule: 1 to 500 parts by mass, and

(In the formula, R ⁴ represents a hydrogen atom or a methyl group, R ⁵ represents a hydrogen atom or a monovalent hydrocarbon group with 1 to 12 carbon atoms, a represents an integer of 1 to 5, and an asterisk (*) represents the bonding site with adjacent atoms .) (D) Photopolymerization initiator: 0.01-20 parts by mass, 2. A cured product, which is the cured product of the ultraviolet-curable silicone adhesive composition as described in 1, 3. An adhesive, which contains as 2. The hardened material of 2. 4. An adhesive sheet, which contains the hardened material of 2. 5. An impression for microstructure transfer, which contains the hardened material of 2. 6. The microstructure transfer impression of 5. , Which has at least one convex structure, 7. A microstructure transfer device, which has a microstructure transfer stamp such as 5 or 6, 8. A microstructure holding substrate, which has a microstructure holding substrate that includes 2 Adhesive layer of hardened substance, 9. A microstructure transfer device, which has a microstructure holding substrate such as 8. [Effects of the invention]

The ultraviolet curable silicone adhesive composition of the present invention has good curability, and the cured product has excellent adhesiveness as a temporary fixing material. Therefore, the cured product of the ultraviolet-curable silicone adhesive composition of the present invention has sufficient adhesive force to transfer small components that cannot be transferred with the adhesive force of the original silicone elastomer, and therefore serves as a micro transfer The material is useful.

Hereinafter, the present invention will be specifically explained. The ultraviolet curable silicone adhesive composition of the present invention is characterized by containing: (A) Organopolysiloxane represented by the following general formula (1): 100 parts by mass, (B) containing (a) R ³ ₃ SiO _1/2 unit (where R ³ represents a monovalent hydrocarbon group with 1 to 10 carbon atoms.) and (b) SiO _4/2 unit, and the molar ratio of (a) unit to (b) unit is Organopolysiloxane resin in the range of 0.6 to 1.2:1: 1 to 1,000 parts by mass, (C) (meth)acrylamide compound having at least one group represented by the following formula (2) in 1 molecule : 1 to 500 parts by mass, and (D) photopolymerization initiator: 0.01 to 20 parts by mass.

(A) Organopolysiloxane The (A) component used in the present invention is a crosslinking component of the composition, and is an organopolysiloxane represented by the following general formula (1).

In the formula (1), R ¹ independently represents a polymerization selected from the group consisting of acryloxyalkyl, methacryloxyalkyl, acryloxyalkoxy and methacryloxyalkoxy. Or a monovalent hydrocarbon group with 1-20 carbon atoms, but at least one of R ¹ is a polymerizable group, R ² independently represents an oxygen atom or an alkylene group with 1-20 carbon atoms, m and n Represents the number satisfying m≧0, n≧1, 1≦m+n≦1,000.

The monovalent hydrocarbon group having 1 to 20 carbon atoms in R ¹ may be any of linear, branched, and cyclic. Specific examples thereof include methyl, ethyl, n-propyl, and isopropyl. , N-butyl, isobutyl, tert-butyl, n-hexyl, cyclohexyl, n-octyl, 2-ethylhexyl, n-decyl and other alkyl groups; vinyl, allyl (2- Allyl), 1-propenyl, isopropenyl, butenyl and other alkenyl groups; phenyl, tolyl, xylyl, naphthyl and other aryl groups; benzyl, phenethyl, phenylpropyl and other aralkyl groups Wait. In addition, part or all of the hydrogen atoms bonded to the carbon atoms of the monovalent hydrocarbon groups may be substituted by other substituents. Specific examples thereof include chloromethyl, bromoethyl, trifluoropropyl, and cyano Halogen substituted hydrocarbon groups such as ethyl, or cyano substituted hydrocarbon groups, etc. Among them, in addition to the aliphatic unsaturated group, a monovalent hydrocarbon group having 1 to 8 carbon atoms is preferred, an alkyl group having 1 to 5 carbon atoms or a phenyl group is more preferred, and methyl and ethyl are more preferred.基, phenyl. In particular, in terms of ease of synthesis and cost, it is preferable that 90% or more of R ¹ is methyl or phenyl.

On the other hand, the polymerizable group of R ¹ is selected from polymerization of acryloxyalkyl, methacryloxyalkyl, acryloxyalkoxy, or methacryloxyalkoxy The carbon number of the alkane (alkylene) group in the functional group is not particularly limited, but is preferably 1-10, more preferably 1-5. Specific examples of these alkyl groups include those having 1 to 10 carbon atoms among the monovalent hydrocarbon groups exemplified above. As a specific example of a polymerizable group, what is shown by the following formula can be mentioned, but it is not limited to these.

(式中，b表示滿足1≦b≦4之數，R⁷ 表示碳原子數1～10的伸烷基。)

(In the formula, b represents a number satisfying 1≦b≦4, and R ⁷ represents an alkylene group having 1 to 10 carbon atoms.)

The alkylene group having 1 to 10 carbon atoms in R ⁷ may be any of linear, branched, and cyclic. Specific examples include methylene, ethylene, propylene, trimethylene, and tetramethylene. Group, isobutylene, pentamethylene, hexamethylene, heptamethylene, octamethylene, nonamethylene, decylene, etc., but preferably methylene, ethylene, and triethylene methyl.

As described above, in the organopolysiloxane represented by formula (1), at least one of R ¹ is a polymerizable group, but preferably 1 to 6 are polymerizable groups, and more preferably 2 to 4 are Polymeric base. In addition, the polymerizable group may be present at either the terminal or the side chain of the molecular chain of the organopolysiloxane, and it is preferably present only at the terminal in terms of flexibility.

In addition, the alkylene group having 1 to 20 carbon atoms in R ² may be any of linear, branched, and cyclic, and specific examples thereof include methylene, ethylene, propylene, and trimethylene Group, tetramethylene, isobutylene, pentamethylene, hexamethylene, heptamethylene, octamethylene, nonamethylene, decylene, etc. Among them, R ^{2 is} preferably an oxygen atom, a methylene group, an ethylene group, or a trimethylene group, and more preferably an oxygen atom or an ethylene group.

In formula (1), m and n are numbers satisfying m≧0, n≧1, 1≦m+n≦1,000, but preferably satisfying 1≦m+n≦700, and more preferably satisfying 20≦ The number of m+n≦500. If m+n is less than 1, it is easy to volatilize, and if m+n exceeds 1,000, the viscosity of the composition becomes high and workability is poor.

(A) The viscosity of the organopolysiloxane of the component at 25°C is preferably 10 to 100,000 mPa･s, more preferably 10 to 50,000 if considering the improvement of the workability of the composition or the mechanical properties of the cured product. mPa･s. In addition, in the present invention, the viscosity can be measured by a rotary viscometer (for example, BL type, BH type, BS type, cone-plate type, rheometer, etc.) (the same applies below).

As specific examples of the organopolysiloxane of the component (A), those represented by the following formulas (3) and (4) may be mentioned, but they are not limited thereto. In addition, in the following formula, Me represents a methyl group, and Ph represents a phenyl group.

(式(4)中，括弧內的矽氧烷單位的排列順序為任意。)

(In formula (4), the order of the siloxane units in parentheses is arbitrary.)

Moreover, the organopolysiloxane of the said (A) component may be used individually or in combination of 2 or more types.

(B) Organopolysiloxane resin (B) component is a component that imparts adhesiveness to the cured product, including (a) R ³ ₃ SiO _1/2 unit (where R ³ represents a monovalent carbon number of 1-10 Hydrocarbyl group.) and (b) SiO _4/2 unit, and the molar ratio of (a) unit to (b) unit is an organopolysiloxane resin in the range of 0.6 to 1.2:1. Specific examples of the monovalent hydrocarbon group having 1 to 10 carbon atoms in R ³ include those having 1 to 10 carbon atoms among the groups exemplified in R ¹ above. Among them, methyl, ethyl, and Alkyl groups with 2-6 carbon atoms such as n-propyl and n-butyl; aryl groups with 6-10 carbon atoms such as phenyl and tolyl; aralkyl groups with 7-10 carbon atoms such as benzyl; Alkenyl groups having 2 to 6 carbon atoms such as vinyl, allyl and butenyl. In addition, the above-mentioned monovalent hydrocarbon group of R ³ is also the same as that of R ¹ , part or all of the hydrogen atoms bonded to the carbon atoms may be substituted with the above-mentioned other substituents.

In the component (B) of the present invention, the molar ratio of (a) R ³ ₃ SiO _1/2 unit (M unit) and (b) SiO _4/2 unit (Q unit) is M unit: Q unit = 0.6～ 1.2:1, but if the molar ratio of the M unit is less than 0.6, the adhesion and tackiness of the cured product may decrease, and if it exceeds 1.2, the adhesion and retention of the cured product may decrease. Happening. In consideration of setting the adhesion, retention, and tackiness of the hardened product to a more appropriate range, it is preferable that the molar ratio of the M unit and the Q unit is M unit: Q unit = 0.7 to 1.2:1.

The addition amount of the organopolysiloxane resin of the component (B) is in the range of 1 to 1,000 parts by mass relative to 100 parts by mass of the above-mentioned (A) component, but is preferably 5 to 500 parts by mass, more preferably 10 to 300 Mass parts. With respect to 100 parts by mass of the component (A), if the added amount is less than 1 part by mass, the adhesive force of the cured product becomes insufficient, and if it is more than 1,000 parts by mass, the viscosity becomes remarkably high, and the workability is poor.

(C)(Meth)acrylamide compound The component (C) is a component that enhances the adhesive force of the composition and improves the curability, and is a compound having at least one group represented by the following formula (2) in one molecule. Here, (meth)acrylamide means acrylamide or methacrylamide. By including the component (C) in the composition, the adhesive force after curing can be improved. Furthermore, since this component functions as a hardening reaction sensitizer by radical polymerization, the hardenability (total hardening property) of this composition can be improved.

(式中，星號(＊)表示與相鄰原子的鍵結部位。)

(In the formula, the asterisk (*) indicates the bonding site with adjacent atoms.)

In the formula (2), R ⁴ represents a hydrogen atom or a methyl group, R ⁵ represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 12 carbon atoms, and a represents an integer of 1 to 5. Specific examples of the monovalent hydrocarbon group having 1 to 12 carbon atoms for R ⁵ include those having 1 to 12 carbon atoms among the groups exemplified in R ¹ above, but among them, methyl, ethyl, n -Alkyl groups with 2 to 6 carbon atoms such as propyl and n-butyl; aryl groups with 6 to 10 carbon atoms such as phenyl and tolyl; aralkyl groups with 7 to 10 carbon atoms such as benzyl; ethylene Alkenyl groups having 2 to 6 carbon atoms such as group, allyl group and butenyl group. In addition, the above-mentioned monovalent hydrocarbon group of R ⁵ is also the same as that of R ¹ , part or all of the hydrogen atoms bonded to the carbon atoms may be substituted with the above-mentioned other substituents.

From the viewpoint of compatibility with (A) component and (B) component, the molecular structure of (C) component is preferably: the main chain is a straight chain formed by repeating diorganosiloxane units, and the molecular chain The terminal or side chain is a diorganopolysiloxane terminated with a group represented by the above formula (2). As such (C) component, what is represented by following formula (5) is mentioned, for example.

(式中，0≦p≦3、0≦q≦100，R⁶ 彼此獨立地較佳為除脂肪族不飽和基以外，碳數1～12、較佳為1～10的一價烴基。R⁴ 、R⁵ 、a表示與上述相同意義。)

(In the formula, 0≦p≦3, 0≦q≦100, and R ⁶ independently of each other is preferably a monovalent hydrocarbon group having 1 to 12, preferably 1 to 10 carbon atoms other than the aliphatic unsaturated group. ^4. R ⁵ and a have the same meaning as above.)

Specific examples of the monovalent hydrocarbon group having 1 to 12 carbon atoms for R ⁶ include those having 1 to 12 carbon atoms among the groups exemplified in R ¹ above, but among them, methyl, ethyl, n -Alkyl groups with 2 to 6 carbon atoms such as propyl and n-butyl; aryl groups with 6 to 10 carbon atoms such as phenyl and tolyl; aralkyl groups with 7 to 10 carbon atoms such as benzyl; ethylene Alkenyl groups having 2 to 6 carbon atoms such as group, allyl group and butenyl group. In addition, the above-mentioned monovalent hydrocarbon group of R ⁶ may be substituted by the above-mentioned other substituents with a part or all of the hydrogen atoms bonded to carbon atoms, similarly to R ¹ .

(C) As the component, the lower the molecular weight, the better the function as a curable sensitizer. Therefore, the molecular weight is preferably 2,000 or less, and more preferably 1,000 or less.

The blending amount of the (C) component is in the range of 1 to 500 parts by mass with respect to 100 parts by mass of the (A) component, but is preferably 5 to 100 parts by mass, more preferably 10 to 50 parts by mass. If the addition amount of the component (C) is too small, the effect of imparting adhesive force to the cured product cannot be expected, and there is a doubt that it cannot function as a curing reaction sensitizer. Moreover, (C)component may be used individually by 1 type, and may be used in combination of 2 or more types.

(D) Photopolymerization initiator As specific examples of the photopolymerization initiator that can be used in the present invention, 2,2-diethoxyacetophenone, 2,2-dimethoxy-1,2-diphenylethane- 1-ketone (Irgacure 651 made by BASF), 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184 made by BASF), 2-hydroxy-2-methyl-1-phenyl-propane-1-one (made by BASF) Irgacure 1173), 2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl-propanyl)-benzyl]-phenyl}-2-methyl-propan-1-one ( Irgacure 127 manufactured by BASF), methyl phenylglyoxylate (Irgacure MBF manufactured by BASF), 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one ( Irgacure 907 manufactured by BASF, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-1-butanone (Irgacure 369 manufactured by BASF), bis(2,4,6-tri Methylbenzyl)-phenylphosphine oxide (Irgacure 819 made by BASF), 2,4,6-trimethylbenzyl-diphenyl-phosphine oxide (Irgacure TPO made by BASF), etc. It can be used alone or in combination of two or more kinds. Among them, from the viewpoint of compatibility with the component (A), 2,2-diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenyl-propane- 1-ketone (Irgacure 1173 manufactured by BASF), bis(2,4,6-trimethylbenzyl)-phenylphosphine oxide (Irgacure 819 manufactured by BASF), 2,4,6-trimethylbenzyl -Diphenyl-phosphine oxide (Irgacure TPO manufactured by BASF).

The addition amount of the photopolymerization initiator is in the range of 0.01 to 20 parts by mass relative to 100 parts by mass of (A). If it is less than 0.01 parts by mass, the curability is insufficient, and when it is added in an amount exceeding 20 parts by mass, the deep curability deteriorates.

The ultraviolet curable silicone adhesive composition of the present invention may contain a monofunctional or polyfunctional (meth)acrylate compound without a silicone structure in order to further improve the curability. The term “(meth)acrylate” here means acrylate or methacrylate. Specific examples of monofunctional (meth)acrylate compounds that do not have a silicone structure include isoamyl acrylate, lauryl acrylate, stearyl acrylate, ethoxy-diethylene glycol acrylate, and methyl acrylate. Oxy-triethylene glycol acrylate, 2-ethylhexyl-diethylene glycol acrylate, phenoxyethyl acrylate, phenoxydiethylene glycol acrylate, tetrahydrofurfuryl acrylate, isobornyl acrylate, etc. As specific examples of multifunctional (meth)acrylate compounds that do not contain a silicone structure, triethylene glycol diacrylate, polytetramethylene glycol diacrylate, neopentyl glycol diacrylate can be mentioned Esters, 1,6-hexanediol diacrylate, dimethylol-tricyclodecane diacrylate, trimethylolpropane triacrylate, pentaerythritol tetraacrylate, etc.

In addition, the composition of the present invention can be added as a filler for the purpose of reinforcing silicone rubber, adjusting viscosity, improving heat resistance, improving flame retardancy, etc., within the range that does not impair the effects of the present invention. . Examples of fillers include reinforcing fillers such as fumed titanium oxide; non-reinforcing fillers such as iron oxide, alumina, calcium carbonate, and magnesium carbonate; and organosilicon such as organosilane and organopolysiloxane Compounds processed these fillers, etc. In addition, additives such as silane coupling agents, polymerization inhibitors, antioxidants, oxygen absorbers as light stabilizers, and light stabilizers may also be blended in the composition of the present invention. Furthermore, the composition of the present invention can be appropriately mixed and used with other resin compositions.

The ultraviolet curable silicone adhesive composition of the present invention can be obtained by mixing the above-mentioned components (A) to (D) and other components as necessary in an arbitrary order, and then stirring. The device used for stirring and other operations is not particularly limited, but a crusher, three-roller, ball mill, planetary mixer, etc. can be used. Moreover, these devices can be combined appropriately.

The viscosity of the ultraviolet-curable silicone adhesive composition of the present invention is preferably in the range of 0.01-100 Pa･s at a rotation speed of 10 rpm measured at 23°C from the viewpoint of workability. , More preferably 0.1～80 Pa･s, still more preferably 1～50 Pa･s.

The ultraviolet curable silicone adhesive composition of the present invention is rapidly cured by irradiating ultraviolet rays. At this time, as a light source for irradiating ultraviolet rays, for example, a UV LED lamp, a high-pressure mercury lamp, an ultra-high pressure mercury lamp, a metal halide lamp, a carbon arc lamp, a xenon lamp, etc. may be mentioned. For example, when the composition of the present invention is formed into a sheet having a thickness of about 2.0 mm, the amount of ultraviolet radiation (cumulative light amount) is preferably 1 to 10,000 mJ/cm ² , and more preferably 10 to 6,000 mJ/cm ² . That is, when using ultraviolet rays with an illuminance of 100 mW/cm ² , it is sufficient to irradiate ultraviolet rays for about 0.01 to 100 seconds. In the present invention, considering the sufficient adhesiveness that can transfer the micro components, the adhesive force of the cured product obtained by ultraviolet irradiation is preferably 0.1-100 MPa, more preferably 0.1-50 MPa.

In addition, the ultraviolet curable silicone adhesive composition of the present invention can be used as an adhesive article by coating on various substrates and curing them with ultraviolet rays. As the substrate, a plastic film, glass, metal, etc. can be used without particular limitation. The plastic film may, for example, be polyethylene film, polypropylene film, polyester film, polyimide film, polyvinyl chloride film, polyvinylidene chloride film, polyvinyl alcohol film, polycarbonate film, polystyrene Film, ethylene-vinyl acetate copolymer film, ethylene-vinyl alcohol copolymer film, cellulose triacetate film, etc. There are no particular restrictions on the thickness or type of glass, and it may be chemically strengthened. In addition, in order to improve the adhesion between the base material and the adhesive layer, it is also used for the base material that has been subjected to primer treatment, plasma treatment, etc. in advance.

The coating method can be, for example, spin coater, chipped wheel coater, lip coater, roll coater, die coater, knife coater, knife coater, bar coater, kiss coater, gravure coater , Screen coating, dip coating, cast coating and other conventional coating methods are appropriately selected and used.

The ultraviolet-curable silicone adhesive composition of the present invention is a solvent-free type, so the method for preparing the cured product can also be potting using a mold. Air bubbles may be involved when it flows into the potting mold, but it can be defoamed by reducing pressure. As the mold, for example, a resist mold in which desired unevenness is provided on a silicon wafer by photoresist can be used. When the cured product is to be removed from the mold after curing, it is preferable to perform a mold release treatment on the container before the composition is poured. As the mold release agent, fluorine-based, silicone-based, and the like can be used.

In addition, the ultraviolet curable silicone adhesive composition of the present invention can be used as it is, but when it is necessary to improve the handling properties, coating properties on the substrate, etc., in the range that does not impair the characteristics of the present invention, it is also allowed to use Use after diluting organic solvent.

As shown in Figs. 1 and 2, the cured product of the ultraviolet-curable silicone adhesive composition of the present invention can be used as stamps 100, 101 for transferring microstructures such as small elements or parts. In FIG. 1, the microstructure transfer stamp 100 is configured to have a cured material layer 300 of the ultraviolet-curable silicone adhesive composition of the present invention on a substrate 200. At this time, the size of the cured product layer 300 may be any size that can be accommodated in the base 200, and may be the same size. The material of the substrate 200 is not particularly limited, and specific examples thereof include plastic film, glass, synthetic quartz, metal, and the like. There are no particular restrictions on the thickness, type, etc., and may be chemically strengthened. In addition, in order to improve the adhesion between the substrate and the adhesive layer, a primer treatment, plasma treatment, etc., which have been previously applied to the substrate may be used. In order to suppress positional deviation during transfer of the microstructure and improve transfer accuracy, it is preferable to use synthetic quartz with high flatness.

The method of forming the cured layer 300 on the substrate 200 is not particularly limited. For example, the method of directly coating the uncured UV-curable silicone adhesive composition on the substrate 200 and curing it is the same as that of the substrate 200 Any one of the methods for laminating the sheet-shaped cured product of the ultraviolet-curing silicone adhesive composition. In the method of directly coating and curing the ultraviolet-curing silicone adhesive composition on the substrate 200, the silicone adhesive composition is coated on the substrate 200 and then cured by ultraviolet radiation to obtain micro Stamp 100 for structure transfer. As the coating method, for example, from spin coater, chipped wheel coater, lip coater, roll coater, die coater, knife coater, knife coater, bar coater, kiss coater, gravure coating Appropriate selection and use of conventional coating methods such as screen coating, dip coating, and casting coating. In addition, after the silicone adhesive composition is applied to the substrate by these methods, it is cured by irradiating ultraviolet rays while performing press forming or compression forming, so that a microstructure with high flatness can be obtained. Stamp 100 for structure transfer.

In the method of laminating the sheet-shaped cured product of the ultraviolet-curable silicone adhesive composition on the substrate 200, the microstructure transfer can be obtained by forming the material into a sheet shape and then attaching it to the substrate 200 Use impression 100. As a method of forming the ultraviolet-curable silicone adhesive composition into a sheet shape, for example, it can be appropriately selected and used from forming methods such as roll forming, press forming, transfer forming, and compression forming. In order to prevent adhesion of dust and the like, or to inhibit oxygen inhibition during curing, the sheet-shaped cured product is preferably formed in a form sandwiched between a plastic film. In addition, when the obtained sheet-shaped cured product is larger than desired, it may be cut to a desired size. In addition, in order to improve the adhesion between the cured sheet and the substrate 200, plasma treatment, excimer treatment, chemical treatment, etc. may be performed on the bonding surface of any one or both of these. Furthermore, in order to improve the bonding strength, adhesives/adhesives, etc. may also be used. As specific examples of the adhesive/adhesive agent, silicone-based, acrylic-based, epoxy-based, and the like can be used. As the bonding method, roll bonding, vacuum pressing, or the like can be used.

From the viewpoints of formability and flatness, the thickness of the cured silicone adhesive layer 300 in the microstructure transfer stamp 100 is preferably 1 μm to 1 cm, more preferably 10 μm to 5 mm.

On the other hand, in FIG. 2, the microstructure transfer stamp 101 is configured to have the cured layer 310 of the ultraviolet-curable silicone adhesive composition of the present invention on the substrate 201. The substrate 201 can be the same as the substrate 200. The cured silicone adhesive layer 310 has a convex structure 311 on the surface. In addition, a base layer 312 may be provided under the convex structure 311. The method of forming the hardened layer 310 on the substrate 201 is not particularly limited. For example, a method of directly forming the hardened layer 310 on the substrate 201 by molding or the like, and bonding to the substrate 201 may be mentioned. A method for a sheet-shaped hardened object with a convex structure 311.

The method of directly forming the cured silicone adhesive layer 310 on the substrate 201 by molding, as shown in FIG. 3, is filled with the silicone adhesive composition of the present invention between the substrate 201 and the mold 401. After the ultraviolet rays are irradiated and cured, the mold 401 is released, whereby the stamp 101 for microstructure transfer can be obtained. As the mold 401, for example, a resist mold in which desired unevenness is provided by photoresist on a silicon wafer or a quartz substrate, and a resin mold in which unevenness is provided by pattern exposure to ultraviolet curable resin, etc. can be used. In the case of a resin mold, various plastic films can be used as the base material. As a method of filling the silicone adhesive composition between the substrate 201 and the mold 401, for example, coating the silicone adhesive composition on either or both of the substrate 201 and the mold 401 and then bonding Methods. The coating method or the bonding method can use the above-mentioned methods. Although there is a possibility that fine bubbles remain in the mold 401 during coating, it can be solved by defoaming caused by vacuum bonding or pressure reduction. After the silicone adhesive composition is applied to the substrate by these methods, it is cured by irradiating ultraviolet rays while performing press forming, compression forming, roll forming, etc., to obtain a microstructure transfer stamp 101 .

In addition, as another method, a silicone adhesive composition is screen-printed using a mesh with a desired pattern and then cured by ultraviolet radiation, and a stamp for microstructure transfer can also be obtained. 101. At this time, since the silicone adhesive composition of the present invention has excellent shape retention, it does not damage the desired pattern shape from after application to curing.

In the method of bonding a cured silicone adhesive sheet with a convex structure 311 on a substrate 201, the silicone adhesive composition is formed into a cured sheet with a convex structure 311 and then bonded to the base The material 201 can be used to obtain the stamp 101 for microstructure transfer. As a method of forming an ultraviolet-curable silicone adhesive composition into a sheet-like cured product having a convex structure 311, there are roll forming, press forming, transfer forming, and compression forming using a mold with the same unevenness as the mold 401 Appropriate selection and use among other forming methods. In order to prevent adhesion of dust and the like, or to suppress oxygen inhibition during curing, the sheet-shaped cured product is preferably formed by being sandwiched between a plastic film or the like. In addition, when the obtained sheet-shaped cured product is larger than desired, it may be cut to a desired size. Furthermore, in order to improve the adhesion between the sheet-shaped cured product and the base material 201, plasma treatment, excimer treatment, chemical treatment, etc. may be performed on the bonding surface. In addition, in order to improve the bonding strength, the various adhesives/adhesives mentioned above can also be used. As the bonding method, roll bonding, vacuum pressing, or the like can be used.

The size and arrangement of the convex structure 311 can be designed according to the size of the microstructure of the transfer object or the desired arrangement. The upper surface of the convex structure 311 is flat, and the shape of the surface is not limited, and examples thereof include a circular shape, an oval shape, and a quadrangular shape. When it is a quadrangular shape, the edges can also be rounded. The width of the upper surface of the convex structure 311 is preferably 0.1 μm to 1 cm, more preferably 1 μm to 1 mm. In addition, the shape of the side surface of the convex structure 311 is not limited, and may be a vertical surface, an inclined surface, or the like. The height of the convex structure 311 is preferably 0.1 μm to 1 cm, more preferably 1 μm to 1 mm. The pitch distance between adjacent convex structures 311 separated by a space is preferably 0.1 μm-10 cm, more preferably 1 μm-1 mm. In addition, the thickness of the base layer 312 is preferably 0.1 μm to 1 cm, more preferably 1 μm to 5 mm.

The above-mentioned stamp for transfer of microstructures can be attached to the device and used as a transfer device for microstructures. The method of mounting to the device is not limited, and vacuum clamps, adhesive sheets, etc. may be mentioned. The microstructure transfer device picks up microstructures such as components based on the adhesiveness of the microstructure transfer stamp, moves them to the desired position and releases them, thereby making it possible to achieve the microstructure Transfer.

For example, when performing a laser lift off (LLO) process in which a sapphire substrate of a semiconductor element is peeled from a GaN-based compound crystal layer using laser light, it is used as a temporary For the fixed microstructure holding substrate (donor substrate), the microstructure transfer stamps 100 and 101 shown in FIGS. 1 and 2 can be used. By performing laser irradiation in a state where the semiconductor element and the microstructure holding substrate are adhered, the peeled semiconductor element is transferred/temporarily fixed on the microstructure holding substrate. Furthermore, by using the microstructure transfer stamps 100 and 101 that have a greater adhesion force than the microstructure holding substrate, it is possible to selectively pick up semiconductor elements temporarily fixed on the microstructure holding substrate. Here, after the picked up semiconductor element is moved to the desired position on the mounting target substrate, the semiconductor element and the mounting target substrate are soldered and joined, and the microstructure transfer stamp is peeled from the semiconductor element, thereby achieving the semiconductor element Transfer and installation on the substrate. [Example]

Hereinafter, examples and comparative examples are given to explain the present invention more specifically, but the present invention is not limited by these examples. In addition, the compounds of each component used in the examples are as follows. In the following formulae, Me represents a methyl group and Ph represents a phenyl group.

(式(A-1)中，括弧內之矽氧烷單位的排列順序為任意。)(A) Ingredient

(In formula (A-1), the order of siloxane units in parentheses is arbitrary.)

(B) The component contains Me ₃ SiO _1/2 unit and SiO ₂ unit, and the molar ratio of (Me ₃ SiO _1/2 unit)/(SiO ₂ unit) is 0.85 organopolysiloxane resin (number average molecular weight) 3,500) 60% by mass toluene solution

(C) Component (C-1) An acrylamide compound represented by the following formula (molecular weight: 407.8)

(C-2) An acrylamide compound represented by the following formula (molecular weight: 492.0)

(D) Ingredients 2-Hydroxy-2-methyl-1-phenyl-propan-1-one (Irgacure 1173 manufactured by BASF Japan)

[Examples 1 to 4, Comparative Examples 1 to 2] Mix the above-mentioned components (A) and (B) in the proportions shown in Table 1. After the toluene is distilled off at 100°C under reduced pressure, add the components (C) and (D) in the proportions in Table 1 and mix them with a planetary mixer , Prepare each silica composition described in Table 1. In addition, the viscosity of the composition in Table 1 is a value measured at a rotation speed of 10 rpm using a rotary viscometer at 23°C.

For each silicon-oxygen composition that has been prepared, the Eye UV electronic control device (model UBX0601-01) manufactured by Aeguraflex Co., Ltd. (model UBX0601-01) is used in a nitrogen atmosphere at room temperature (25°C) with a wavelength of 365 nm Irradiate ultraviolet light so that the amount of ultraviolet light irradiation becomes 8,000 mJ/cm ² to harden it. In addition, the thickness of the sheet is 2.0 mm. Measure the hardness of the hardened product according to JIS-K6249. The adhesive force of the hardened material was measured by the small desktop tester EZ-SX manufactured by Shimadzu Corporation. Specifically, it is a value obtained by pressing a 1 mm square SUS probe against a 1 mm thick hardened material at 1 MPa for 15 seconds, and then measuring the load applied when it is stretched at a speed of 200 mm/min. .

As shown in Table 1, it is known that the ultraviolet curable silicone adhesive composition prepared in Examples 1 to 4 has good curability, and the cured product has the adhesive force that can be transferred with the original silicone elastomer. Sufficient adhesion for tiny components that cannot be transferred. On the other hand, in Comparative Example 1 which does not contain the component (C), only a small adhesive force can be obtained, and in Comparative Example 2, the curing is insufficient.

100, 101: Impressions for transfer of microstructures 200,201: substrate 300, 310: Hardened layer 311: Convex structure 312: basal layer 401: Mould

Fig. 1 is a schematic diagram showing an example of the stamp for transferring the microstructure of the present invention. Fig. 2 is a schematic diagram showing an example of the stamp for transferring the microstructure of the present invention. Fig. 3 is a schematic diagram showing an example of the method of manufacturing the stamp for microstructure transfer of the present invention.

Claims (9)

An ultraviolet curable silicone adhesive composition characterized by containing: (A) Organopolysiloxane represented by the following general formula (1): 100 parts by mass,

(In the formula, R ¹ independently represents a polymerizable group selected from the group consisting of acryloxyalkyl, methacryloxyalkyl, acryloxyalkoxy, and methacryloxyalkoxy. , Or a monovalent hydrocarbon group with 1 to 20 carbon atoms, at least one of R ¹ is the aforementioned polymerizable group, R ² independently represents an oxygen atom or an alkylene group with 1 to 20 carbon atoms, m and n represent m≧0, n≧1, 1≦m+n≦1,000) (B) Contains (a) R ³ ₃ SiO _1/2 unit (where R ³ represents a monovalent hydrocarbon group with 1 to 10 carbon atoms ) _{Organopolysiloxane} resin with (b) SiO _4/2 unit, and the molar ratio of (a) unit to (b) unit in the range of 0.6 to 1.2:1: 1 to 1,000 parts by mass, (C) A (meth)acrylamide compound having at least one group represented by the following formula (2) in one molecule: 1 to 500 parts by mass, and

(In the formula, R ⁴ represents a hydrogen atom or a methyl group, R ⁵ represents a hydrogen atom or a monovalent hydrocarbon group with 1 to 12 carbon atoms, a represents an integer of 1 to 5, and an asterisk (*) represents the bonding site with adjacent atoms ) (D) Photopolymerization initiator: 0.01-20 parts by mass. A cured product, which is a cured product of the ultraviolet-curable silicone adhesive composition of claim 1. An adhesive comprising a hardened substance as claimed in claim 2. An adhesive sheet containing the hardened substance as claimed in claim 2. A stamp for transfer of microstructures, which contains the cured product as claimed in claim 2. Such as claim 5, the microstructure transfer stamp, which has at least one convex structure. A microstructure transfer device, which has the stamp for microstructure transfer according to claim 5 or 6. A microstructure holding substrate, which has an adhesive layer containing the hardened substance as claimed in claim 2. A microstructure transfer device having the microstructure holding substrate as claimed in claim 8.

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