JPWO2019073978A1 - Adhesive method and photocurable pressure-sensitive adhesive composition - Google Patents

Abstract

When adhering a plurality of adherends using a photocurable pressure-sensitive adhesive composition containing a predetermined monoacrylate, photopolymerization proceeds rapidly even in the presence of oxygen, and long-term light irradiation and oxygen blocking equipment are not required. An adhesive method and a photocurable pressure-sensitive adhesive composition are provided. Adhesive methods for adhering a plurality of adherends include (A) a monoacrylate represented by the following general formula (1) or general formula (2), (B) a radically polymerizable oligomer, and (C) a photoinitiator. A coating step of applying a photocurable pressure-sensitive adhesive composition which exhibits adhesiveness by light irradiation containing and to at least one adherend, and oxygen applied to the photo-curable pressure-sensitive adhesive composition applied to one of the adherends. A light irradiation step of irradiating light emitted from an LED in the presence and a photocurable pressure-sensitive adhesive composition applied to one adherend and irradiated with light to the other adherend (however, the other adherend). It is provided with a step of adhering (excluding the protective sheet on the adhesive surface) as the body. [Chemical formula 1] [Chemical formula 2] (In the general formula (1) and the general formula (2), R1 represents -H or -CH3, R2 is a substituted or unsubstituted alkyl group, or-(CmH2mO) nR3 group. In the − (CmH2mO) nR3 group, m is an integer of 2 to 4, n is an integer of 1 to 30, R3 is −H, or an unsubstituted or substituted alkyl group.

Description

The present invention relates to an adhesive method and a photocurable pressure-sensitive adhesive composition. In particular, the present invention relates to a bonding method using a photocurable pressure-sensitive adhesive composition that is liquid at room temperature and rapidly photocures (makes a pressure-sensitive adhesive) even in air, and a photocurable pressure-sensitive adhesive composition.

In Patent Document 1, a photocurable composition containing a photopolymerizable acrylic acid ester is applied to one of the adherends, and then irradiated with ultraviolet rays to polymerize the acrylic acid ester to increase the viscosity (B-stage). It is said that the adhesiveness is imparted), and a method of adhering and fixing the other adherend in this state is disclosed. As a specific example, the manufacture of a radio frequency identification (RFID) tag using an antenna component as one adherend and an IC chip as the other adherend is shown. In Patent Document 1, a moisture-curable resin is further used for the photocurable composition to ensure adhesion.

As described above, the photocurable composition containing the photopolymerizable acrylic acid ester is applied to one adherend, and the acrylic acid ester is polymerized by light irradiation to impart adhesiveness, and then the other adherend is adhered. The method of adhering the body is considered to be particularly useful in the manufacture of electronic devices. This is because according to such a method, it is easy to peel off the adherend once adhered for alignment or the like. Further, although the same method can be performed by using an adhesive sheet or an adhesive tape, it is often difficult to shape the adhesive sheet or the adhesive tape into a predetermined shape and place it in a predetermined place. This is because it is relatively easy to apply the uncured photocurable composition to a predetermined place according to the bonding method.

However, although the acrylic acid ester has photopolymerizability, it is known that the polymerization is inhibited in the presence of oxygen such as in the air, so that the polymerization does not proceed or long-term light irradiation is performed. It was necessary or it was necessary to irradiate strong light. Actually, in Example 1 of Patent Document 1, phenoxyethyl acrylate is used as the acrylic acid ester, but it takes less than 1 hour for photopolymerization. In the manufacture of electronic devices, it is considered desirable that the progress of photopolymerization takes seconds in terms of productivity. However, when the influence of oxygen inhibition is large, not only the adhesiveness becomes insufficient, but also it may be difficult to even bond the members. Therefore, in order to solve the problem of oxygen inhibition, we introduced equipment for oxygen inhibition measures such as irradiating light in a nitrogen atmosphere and irradiating light with a transparent cover film blocking oxygen. It was necessary to study ways to reduce oxygen inhibition.

Further, in Patent Document 2, the isocyanate group in the isocyanate group-containing compound [a], which is a reaction product of the polyol (a1) and the polyisocyanate (a2), is the hydroxyl group of the hydroxyl group-containing (meth) acrylate (a3). An active energy ray-curable pressure-sensitive adhesive composition containing a hydroxyl group of a saturated alcohol (a4), a polyisocyanate derivative [A] forming a urethane bond, and an ethylenically unsaturated monomer [B], respectively. Is disclosed. The active energy ray-curable pressure-sensitive adhesive composition described in Patent Document 2 is a composition that is cured by irradiation with ultraviolet rays by a high-pressure mercury lamp, and has a good balance between adhesiveness to a substrate and weather resistance.

According to the ultraviolet irradiation by the high-pressure mercury lamp described in Patent Document 2, since the ultraviolet rays having a low wavelength are contained, the photopolymerization initiator having good surface curability is efficiently decomposed, and there is a surface that is less susceptible to oxygen inhibition. However, when a high-pressure mercury lamp is used, a large space is required because a duct for removing the generated ozone is required. In addition, since the energy of ultraviolet rays emitted from the high-pressure mercury lamp is high, the adherend may be damaged, or the heat from the high-pressure mercury lamp may cause thermal damage to the adherend, which is resistant to damage. Must be selected.

Japanese Patent Application Laid-Open No. 2009-530441 Japanese Unexamined Patent Publication No. 2003-155455

The problem to be solved by the present invention is an adhesive method for adhering a plurality of adherends using a photocurable pressure-sensitive adhesive composition containing a predetermined monoacrylate, in which photopolymerization is rapid even in the presence of oxygen. Provided are a bonding method using a photocurable pressure-sensitive adhesive composition that progresses, does not require long-term light irradiation or oxygen blocking equipment, and sufficiently cures even when irradiated with long-wavelength light, and a photo-curable pressure-sensitive adhesive composition. To do.

The present invention is a method of adhering a plurality of adherends in order to achieve the above object, and (A) a monoacrylate represented by the following general formula (1) or general formula (2), and (B). A coating step of applying a photocurable pressure-sensitive adhesive composition containing a radically polymerizable oligomer and (C) a photoinitiator, which exhibits adhesiveness by light irradiation, to at least one adherend, and to one adherend. A light irradiation step of irradiating the applied photocurable pressure-sensitive adhesive composition with light emitted from an LED in the presence of oxygen, and a photo-curable pressure-sensitive adhesive composition applied to one of the adherends and irradiated with light. An adhesion method comprising the step of adhering the other adherend (provided that the other adherend is excluding the protective sheet on the adhesive surface) is provided.

In the above general formulas (1) and (2), R ¹ represents −H or −CH ₃ , and R ² is a substituted or unsubstituted alkyl group, or − ( _Cm H _2m O) _n R ³ Indicates a group, in-( _Cm H _2m O) _n R ³ groups, m is an integer of 2 to 4, n is an integer of 1 to 30, R ³ is -H, or an unsubstituted or substituted alkyl group. ..

Further, in the above-mentioned bonding method, the photocurable pressure-sensitive adhesive composition may further contain (D) a pressure-sensitive adhesive resin.

Further, in order to achieve the above object, the present invention provides a method for producing an adhesive body produced by using any of the above bonding methods.

Further, in order to achieve the above object, the present invention is a photocurable pressure-sensitive adhesive composition that exhibits adhesiveness by irradiation with light emitted from an LED in the presence of oxygen, wherein (A) the following general formula (1) or A photocurable pressure-sensitive adhesive composition containing a monoacrylate represented by the general formula (2), (B) a radically polymerizable oligomer, and (C) a photoinitiator is provided.

In the above general formulas (1) and (2), R ¹ represents −H or −CH ₃ , and R ² is a substituted or unsubstituted alkyl group, or − ( _Cm H _2m O) _n R ³ Indicates a group, in-( _Cm H _2m O) _n R ³ groups, m is an integer of 2 to 4, n is an integer of 1 to 30, R ³ is -H, or an unsubstituted or substituted alkyl group. ..

According to the bonding method and the photocurable pressure-sensitive adhesive composition according to the present invention, when a plurality of adherends are bonded using the photo-curable pressure-sensitive adhesive composition containing a predetermined monoacrylate, even in the presence of oxygen. Adhesive method using a photo-curable pressure-sensitive adhesive composition that allows rapid progress of photopolymerization, does not require long-term light irradiation or oxygen blocking equipment, and sufficiently cures even when irradiated with long-wavelength light, and photo-curable adhesive An agent composition can be provided.

It is a schematic diagram of the printed circuit board used for the LED chip bonding test, and the LED chip. It is a schematic diagram of the process of sticking an LED chip to a printed circuit board.

The adhesive method of the present invention is not a method for manufacturing an adhesive product such as an adhesive sheet or an adhesive tape, but a raw material as an adhesive is directly applied to an adherend by irradiating light emitted from a light emitting diode (Light Emitting Mode: LED). Then, a pressure-sensitive adhesive is generated on the adherend, and the other adherend is adhered to the adhesive. That is, in the bonding method of the present invention, the photocurable pressure-sensitive adhesive composition is not used after being formed into a shape such as a tape, but is directly applied to one adherend and directly applied to the other adherend. It is used for adhesion (that is, the other adherend is not a film or the like such as a release liner, but an adherend that is actually adhered to one adherend).

The bonding method of the present invention can be used for bonding electronic / electrical parts and the like, and is particularly suitable for bonding electronic parts. Here, in the present invention, "for on-site construction" means that the composition is used as it is for bonding at a site where electronic parts and the like are manufactured. That is, in the present invention, the adhesive is processed into a shape such as tape to prepare a molded body, and the composition is applied to one of the adherends as it is, instead of using the molded body at a place different from the processing place. However, it refers to the use of attaching one adherend to the other adherend in that state (or at the site).

Further, the photocurable pressure-sensitive adhesive composition of the present invention is a composition that quickly exhibits adhesiveness when irradiated with light such as active energy rays. That is, the photocurable pressure-sensitive adhesive composition has (A) a monoacrylate having a specific structure capable of exhibiting flexibility and suppressing oxygen inhibition by oxygen in the environment, and (B) improving the stickiness (meth). ) Acryloyloxy group (CH ₂ = CR'C (= O) O−; R'represents hydrogen or methyl group.)) Containing polymer and (C) compound that generates radicals by light irradiation. .. Specifically, the photocurable pressure-sensitive adhesive composition of the present invention comprises a monoacrylate represented by the following general formula (1) or general formula (2) as the A component, a radically polymerizable oligomer as the B component, and the like. Contains a photoinitiator as a C component. Further, the photocurable pressure-sensitive adhesive composition may further contain (D) a tack-imparting resin.

Since a specific monoacrylate is used as the component A in the present invention, the pressure-sensitive adhesive has good flexibility and exhibits good adhesiveness. From the viewpoint of improving the flexibility of the adhesive and maintaining / improving the adhesive strength, the Asuka C hardness is preferably 60 or less, and more preferably 50 or less when the photoinitiator is added only to the component A and cured. It is preferably 40 or less, and most preferably 40 or less.

In the general formula (1) and the general formula (2), R ¹ represents −H or −CH ₃ , and R ² is a substituted or unsubstituted alkyl group, or − ( _Cm H _2m O) _n R ³ groups. Is shown. Here, in − ( _Cm H _2m O) _n R ³ groups, m is an integer of 2 to 4, n is an integer of 1 to 30, and R ³ is −H, or an unsubstituted or substituted alkyl group. Specifically, examples of _{^{R 2, - (C m H}} 2m O) n group in ^{R 3} groups ^{wherein R 3} is a hydroxyl group of _{H ;-( C m H 2m O)} n R in ³ groups ^{wherein R 3} is unsubstituted Alternatively, a group having an alkoxy group as a substituted alkyl group can be mentioned.

The substituted or unsubstituted alkyl group is not particularly limited, but for example, an alkyl group having 1 to 30 carbon atoms is preferable. The alkyl group shall contain an alkyl group (alkyl group in a broad sense) including a group having a double bond. Further, the substituted or unsubstituted alkyl group may be linear, branched or cyclic. The substituent in the substituted alkyl group is not particularly limited, and examples thereof include a halogen atom, a hydroxyl group, an alkoxy group, an ester group, a ketone group, an aldehyde group, a carboxyl group, a glycidyl group, an amino group, an amide group and the like. Be done. The alkoxy group is not particularly limited, but an alkoxy group having 1 to 30 carbon atoms is preferable, and an alkoxy group having 1 to 18 carbon atoms is more preferable. Further, as the ester group, an ester group having 2 to 30 carbon atoms is preferable, and an ester group having 2 to 18 carbon atoms is more preferable. As the ketone group, a ketone group having 2 to 30 carbon atoms is preferable, and a ketone group having 2 to 18 carbon atoms is more preferable.

Further, an alkyl group in which R ² is unsubstituted is preferable because of its availability. From the viewpoint of good flexibility of the cured product and maintenance / improvement of adhesive strength, an alkyl group having 1 to 30 carbon atoms is preferable, an alkyl group having 4 to 20 carbon atoms is more preferable, and an alkyl group having 8 carbon atoms is more preferable. Alkyl groups of ~ 18 are more preferred.

Further, from the viewpoint of improving the flexibility of the cured product and maintaining / improving the adhesive strength, R ² may be a long-chain hydrocarbon group having 8 to 20 carbon atoms or a group having a crosslinkable silicon group. .. A long-chain hydrocarbon group having 8 to 20 carbon atoms and / or − ( _Cm H _2m O) _n R ³ groups is preferable, and the adhesive has 8 to 20 carbon atoms, because the adhesive has excellent flexibility. A long-chain hydrocarbon group, a group having a hydroxyl group, and a group having an alkoxy group are more preferable, and a long-chain hydrocarbon group having 8 to 20 carbon atoms is most preferable. A group having a crosslinkable silicon group is preferable from the viewpoint of curing the composition by a dual curing mechanism that also undergoes a curing reaction by moisture curing.

Specific examples of R ² are as follows. First, examples of the group having a hydroxyl group include a 2-hydroxypropyl group, a 4-hydroxybutyl group, a hydroxyhexa (ethylene ether) group, a hydroxyocta (propylene ether) group, a 2-hydroxy-3-butyloxypropyl group and the like. Be done. Examples of the group having an alkoxy group include a methoxytri (ethylene ether) group, an ethoxydi (ethylene ether) group, a dicyclopentenyloxyethyl group and the like. Examples of the long-chain hydrocarbon group having 8 to 20 carbon atoms include a 2-ethylhexyl group, an isooctyl group, a lauryl group, and an isostearyl group, which have a long carbon number of 8 to 18 from the viewpoint of availability. Chain hydrocarbon groups are preferred. Examples of the alicyclic group include a cyclohexyl group, a dicyclopentenyl group, an isobornyl group and the like. Examples of the (meth) acryloyloxy group having a crosslinkable silicon group include a 3- (trimethoxysilyl) propyl group, and the composition containing such a group undergoes a moisture curing reaction to form a dual curing mechanism.

(Component A: Monoacrylate having a (meth) acrylic acid-2-hydroxy-3-alkoxy group)
The component A contained in the photocurable pressure-sensitive adhesive composition is a compound having a plurality of electron-withdrawing groups, and is a compound in which active radicals are likely to be generated in a portion sandwiched between the plurality of electron-withdrawing groups. The present inventors speculate that a compound having such a structure can suppress polymerization inhibition by oxygen, and as a result of studying the characteristics of a photocurable pressure-sensitive adhesive composition using various compounds, the present invention relates to the present invention. It has been found that the component A of the photocurable pressure-sensitive adhesive composition is suitable. That is, as the A component, a secondary hydroxyl group arranged in a portion sandwiched between a plurality of -CH ₂ groups (specifically, two -CH ₂ groups) and an electron-withdrawing group located at both ends of the molecule. It has been found that monofunctional compounds containing are preferred. Specifically, the component A is referred to as a monoacrylate represented by the general formula (1) or the general formula (2) (hereinafter, a monoacrylate having a -2-hydroxy-3-propyl (meth) acrylate group). In some cases). Specific examples of the component A include alkyl 2-hydroxy-3-alkoxypropyl (meth) acrylate having 4 to 18 carbon atoms, 2-hydroxy-3-alkylcarbonyloxypropyl (meth) acrylate and the like.

Here, the effect of the present invention can be obtained with a monoacrylate having a hydroxyl group (for example, 4-hydroxybutyl acrylate, 2-hydroxybutyl acrylate, etc.) other than the monoacrylate represented by the general formula (1) or the general formula (2). I can't.

From the viewpoint of making the pressure-sensitive adhesive obtained from the composition and the cured product obtained by post-curing the pressure-sensitive adhesive a cured product having more flexibility than the cured product obtained from epoxy acrylate, acrylamide, etc., and / or epoxy acrylate, acrylamide, etc. From the viewpoint of using a compound having a glass transition temperature relatively lower than the glass transition temperature of the above, monoacrylate is used as the component A instead of polyfunctionality.

Here, the following mechanism is presumed as a mechanism for suppressing polymerization inhibition by oxygen. That is, in radical polymerization, polymerization inhibition by oxygen occurs, and the reaction rate of the monomer decreases. In particular, a decrease in the reaction rate occurs in the surface layer that comes into contact with air. Oxygen inhibition occurs when the polymerization ability of the initiation radical generated from the photoinitiator or the polymerization terminal radical generated in the polymerization process of the monomer is trapped in oxygen and the peroxy radical generated is low, and the polymerization reaction is stopped. Here, when the monoacrylate of the component A having a function as a chain transfer agent is present in the system, the peroxy radical having a hydrogen abstraction ability abstracts hydrogen from the monoacrylate to newly generate α of the secondary hydroxyl group. It is believed that the carbon radicals initiate polymerization. Further, since the generated α-carbon radical of the secondary hydroxyl group can supplement oxygen, the effect of reducing the oxygen concentration in the system can be considered. It is speculated that these mechanisms suppress oxygen inhibition.

The monoacrylate of component A is a low molecular weight compound having a molecular weight of 1,000 or less. The molecular weight is preferably 750 or less, more preferably 500 or less, from the viewpoint of ensuring an appropriate viscosity of the composition and ensuring good workability. The molecular weight means, for example, a number average molecular weight when the − ( _Cm H _2m O) _n R ³ group contains a plurality of n values.

Further, the monoacrylate of the component A is preferably liquid at 50 ° C. That is, from the viewpoint of ensuring ease of handling when blended with other components, it is preferable to show a liquid at 50 ° C, more preferably to show a liquid at 20 ° C, and further to show a liquid at 0 ° C. preferable.

(B component: radically polymerizable oligomer)
The radically polymerizable oligomer as the B component is an oligomer having a number average molecular weight of 1,000 or more, and improves the adhesive strength. The radically polymerizable group in the radically polymerizable oligomer is contained in the oligomer and / or at the terminal, and the terminal of the urethane oligomer is preferable from the viewpoint of obtaining a pressure-sensitive adhesive having sufficient peel strength. The radically polymerizable groups include (meth) acryloyloxy group (CH ₂ = CR ¹ C (= O) O−) and (meth) acryloyl (substituted) amino group (CH ₂ = CR ¹ C (= O) NH). −), And a compound having a (meth) acryloyloxy group is preferable from the viewpoint of storage stability. From the viewpoint of reactivity, a compound having a (meth) acryloyl (substituted) amino group is preferable. In the case of (meth) acryloyloxy group, 3- (meth) acryloyloxy-2-hydroxypropyl group (CH ₂ = CR ¹ C (= O) O-CH ₂ CH (OH) CH ₂ ) from the viewpoint of reactivity. A compound having −,) is preferable. In addition, R ¹ represents a hydrogen or a methyl group.

Examples of the radically polymerizable oligomer include radically polymerizable urethane oligomers and acrylic (meth) acrylates (for example, "RC-100C", "RC-200C", and "RC-300C" manufactured by Kaneka Co., Ltd .: Patent No. 4786921. Meta) vinyl polymer having acryloyl group), polyisoprene (meth) acrylate (for example, "UC-1" manufactured by Kuraray Co., Ltd .: esterified product of maleic anhydride adduct of polyisoprene polymer and 2-hydroxyethyl methacrylate) ) Etc. can be mentioned. Examples of the main chain skeleton of the radically polymerizable urethane oligomer include a polyether-based, polyester-based, non-aromatic polycarbonate-based, acrylic-based, and diene polymerization-based oligomer / polymer skeleton.

The number average molecular weight of the radically polymerizable oligomer is preferably 2,000 or more, more preferably 3,000 or more in terms of polystyrene in GPC, from the viewpoint of ensuring good elongation characteristics of the pressure-sensitive adhesive. From the viewpoint of ensuring an appropriate viscosity of the composition and ensuring good workability, the number average molecular weight is preferably about 100,000 or less, more preferably 50,000 or less, still more preferably 30,000 or less. Further, from the viewpoint of ensuring ease of handling when blended with other components, it is preferable to show a liquid at 50 ° C, more preferably to show a liquid at 20 ° C, and further to show a liquid at 0 ° C. preferable. A radically polymerizable oligomer having a glass transition point (Tg) of 10 ° C. or lower is preferable, and a radically polymerizable oligomer having a glass transition point (Tg) of 0 ° C. or lower is more preferable, from the viewpoint of giving the pressure-sensitive adhesive flexibility at low temperatures and maintaining / improving the adhesive strength. , −10 ° C. or lower is more preferable.

The mixing ratio of the radically polymerizable oligomer is 500 parts by mass with respect to 100 parts by mass of the A component (or the total of the A component and the monoacrylate having a phenoxy group) from the viewpoint of exerting the effect of suppressing oxygen inhibition by the A component. The following is preferable, 300 parts by mass or less is more preferable, and 200 parts by mass or less is most preferable. From the viewpoint of exerting sufficient cohesive force under high temperature conditions, 5 parts by mass or more is preferable, 10 parts by mass or more is more preferable, and 30 parts by mass or more is most preferable.

(Radical polymerizable urethane oligomer)
The radically polymerizable urethane oligomer can be synthesized by reacting a reaction product of a hydroxyl group-containing oligomer and an organic polyisocyanate with a hydroxyl group-containing radically polymerizable compound. It can also be synthesized by reacting a hydroxyl group-containing oligomer or a hydroxyl-terminated urethane oligomer with an isocyanate group-containing (meth) acrylate. The hydroxyl group-terminated urethane oligomer can be synthesized by reacting the hydroxyl group-containing oligomer with an organic polyisocyanate.

[Hydroxy group-containing oligomer]
The hydroxyl group-containing oligomers include polyether-based hydroxyl group-containing oligomers, polyester-based hydroxyl group-containing oligomers, non-aromatic polycarbonate-based hydroxyl group-containing oligomers, acrylic hydroxyl group-containing oligomers, which have a number average molecular weight of about 1,000 to 50,000. Diene polymerization system Examples thereof include hydroxyl group-containing oligomers. Diol and monool are preferable from the viewpoint of imparting flexibility to the cured product, and diol is preferable from the viewpoint of curability. Further, from the viewpoint of ease of handling at the time of compounding and ease of handling of the composition, a hydroxyl group-containing oligomer liquid at 20 ° C. is preferable. These hydroxyl group-containing oligomers can be used alone or in combination of two or more.

(Polyester-based hydroxyl group-containing oligomer)
Examples of the polyether hydroxyl group-containing oligomer include polyethylene glycol, polypropylene glycol, polyoxyethylene polyoxypropylene glycol, polypropylene triol, and polytetramethylene glycol. Polypropylene glycol (PPG) and polytetramethylene glycol (PTMG) are preferable from the viewpoint of imparting flexibility to the cured product. From the viewpoint of imparting flexibility to the cured product, polypropylene monool is preferable. When improving the degree of cross-linking of the cured product, triol and tetraol are preferable.

Examples of the method for synthesizing the polyoxyalkylene polymer include, but are not limited to, a polymerization method using an alkali catalyst such as KOH and a polymerization method using a compound metal cyanide complex catalyst. According to the polymerization method using a compound metal cyanide complex catalyst, a polyoxyalkylene polymer having a high molecular weight of Mw (weight average molecular weight) / Mn (number average molecular weight) of 1.6 or less and a narrow molecular weight distribution can be obtained. The polypropylene polyol preferably has a Mw / Mn of 1.6 or less from the viewpoint of improving the coating workability of the composition (from the viewpoint of reducing the viscosity). From the viewpoint of imparting flexibility to the cured product, it is preferable to use a polypropylene polyol having a number average molecular weight of 6,000 or more.

(Polyester-based hydroxyl group-containing oligomer)
Examples of the polyester-based hydroxyl group-containing oligomer include a reaction product of a diol component and a polyvalent carboxylic acid, and an addition reaction product of a diol component and a lactone. A liquid polyester-based hydroxyl group-containing oligomer is preferable, and as the diol component, a branched aliphatic glycol having 5 or more carbon atoms such as neopentyl glycol (NPG) and 2-methyl-1,5-pentanediol (MPD) is preferable. Further, as the polyvalent carboxylic acid, a dicarboxylic acid having 5 or more carbon atoms such as adipic acid and sebacic acid is preferable.

(Non-aromatic polycarbonate-based hydroxyl group-containing oligomer)
Examples of the non-aromatic polycarbonate-based hydroxyl group-containing oligomer include a component selected from diol components such as 1,4-butanediol, 1,6-hexanediol, and 1,5-pentanediol, and a short chain such as dimethyl carbonate. Examples thereof include polycarbonate diols that can be obtained by reacting with dialkyl carbonate. In particular, copolymerization of monomers with different unit chain lengths (1,6-hexanediol / 1,5-pentanediol copolymerization, 1,6-hexanediol / 1,4-butanediol copolymerization, etc.) is amorphous. A non-aromatic polycarbonate-based hydroxyl group-containing oligomer that is liquid at 20 ° C. is preferable.

(Acrylic hydroxyl group-containing oligomer)
The acrylic hydroxyl group-containing oligomer is preferably an acrylic hydroxyl group-containing oligomer in which the hydroxyl group is located at the end of the main chain skeleton of the oligomer, and is preferably an acrylic hydroxyl group-containing oligomer that is liquid at 20 ° C. Examples of the (meth) acrylic acid ester-based monomer constituting the main chain of the acrylic hydroxyl group-containing oligomer include methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, and (meth) acrylic acid. Examples thereof include (meth) acrylic acid alkyl esters having 1 to 18 carbon atoms such as 2-ethylhexyl and stearyl (meth) acrylic acid. These may be used alone or in combination of two or more.

Furthermore, by using an alkoxysilyl group-containing (meth) acrylic acid ester such as γ- (meth) acryloyloxypropyltrimethoxysilane in combination, a crosslinkable silicon group can be introduced into the main chain of the acrylic hydroxyl group-containing oligomer. it can. Acrylic acid alkyl ester having 4 to 8 carbon atoms and methacrylic acid alkyl ester having 10 or 12 carbon atoms are preferable, and n-butyl acrylate and 2-ethylhexyl acrylate are more preferable, and acrylic acid is preferable because the cured product has good flexibility. Most preferred is n-butyl acid. The (meth) acrylic acid represents acrylic acid and / or methacrylic acid.

[Crosslinkable silicon group]
A crosslinkable silicon group is a group that has a hydroxyl group or a hydrolyzable group bonded to a silicon atom and can be crosslinked by a silanol condensation reaction. Examples of the crosslinkable silicon group include a crosslinkable silicon group represented by the formula (3).

In the formula, R ⁴ is an alkyl group having 1 to 20 carbon atoms, a substituted alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, and 7 to 20 carbon atoms. shows the aralkyl group, when R ⁴ there are two or more, they may be the same or may be different. X represents a hydrolyzable group, and when two or more Xs are present, they may be the same or different. a indicates 0, 1, 2 or 3. It is preferable that a is 2 or 3 in the crosslinkable silicon group of the formula (3). When a is 3, the curing rate is higher than when a is 2.

Specific examples of the R ^4, for example, alkyl groups such as a methyl group, an ethyl group, a substituted alkyl group such as a methoxymethyl group, a cycloalkyl group such as cyclohexyl group. Of these, a methyl group is preferable, and a substituted alkyl group in which α carbon is substituted with a polar group is preferable from the viewpoint of increasing the curing rate.

The hydrolyzable group represented by X is not particularly limited, and any conventionally known hydrolyzable group may be used. Alkoxy groups are preferable from the viewpoint of mild hydrolysis and easy handling. Among the alkoxy groups, those having a small number of carbon atoms have higher reactivity, and the reactivity decreases as the number of carbon atoms increases in the order of methoxy group> ethoxy group> propoxy group. Although it can be selected according to the purpose and application, a methoxy group or an ethoxy group is usually used. In the case of the crosslinkable silicon group represented by the formula (3), a is preferably 2 or more in consideration of curability.

Specific examples of the crosslinkable silicon group include a trialkoxysilyl group such as a trimethoxysilyl group and a triethoxysilyl group (-Si (OR ⁵ ) ₃ ); a dialkoxysilyl group such as a methyldimethoxysilyl group and a methyldiethoxysilyl group. Alkoxysilyl groups (-SiR ⁴ (OR ⁵ ) ₂ ) can be mentioned. Here, R ⁴ is the same as described above, and R ⁵ is an alkyl group such as a methyl group or an ethyl group. As the crosslinkable silicon group, a trimethoxysilyl group and a triethoxysilyl group are preferable, and a trimethoxysilyl group is more preferable, from the viewpoint of high reactivity. A methyldimethoxysilyl group and a methyldiethoxysilyl group are preferable from the viewpoint of obtaining a cured product having flexibility.

As a method for producing an acrylic hydroxyl group-containing oligomer, a living radical polymerization method is used from the viewpoint of obtaining an acrylic hydroxyl group-containing oligomer having a narrow molecular weight distribution and low viscosity and having a hydroxyl group at the end of the molecular chain. It is preferable to use it.

Further, in the case of obtaining an acrylic hydroxyl group-containing oligomer having a hydroxyl group at one end, a reaction using a thiol compound having a hydroxyl group and a metallocene compound such as 2-mercaptoethanol described in JP-A-2000-344823 can be used. A reaction using a compound having a thiol group and a secondary hydroxyl group such as thioglycerol (3-mercapto-1,2-propanediol) described in JP-A-2000-128911 can also be used. From the viewpoint of good flexibility of the cured product and maintenance / improvement of adhesive strength, an acrylic hydroxyl group-containing oligomer having two hydroxyl groups at one end is preferable.

The number average molecular weight of the acrylic hydroxyl group-containing oligomer is preferably 2,000 or more, preferably 5,000 or more, and even more preferably 8,000 or more, from the viewpoint of ensuring good flexibility of the pressure-sensitive adhesive. From the viewpoint of ensuring an appropriate viscosity of the composition and ensuring good workability, the number average molecular weight is preferably about 100,000 or less, more preferably 50,000 or less, still more preferably 30,000 or less.

(Diene polymerization system, hydroxyl group-containing oligomer)
Examples of the diene polymerization system hydroxyl group-containing oligomer include 1,2-polybutadienediol, a hydrogenated product of 1,2-polybutadienediol, and 1,4-polybutadienediol.

[Organic polyisocyanate]
Examples of the organic polyisocyanate that can be used in the present invention include aromatic polyisocyanates such as tolylene diisocyanate (TDI), aromatic aliphatic polyisocyanates such as xylylene diisocyanate (XDI), and isophorone diisocyanate (IPDI). Examples thereof include alicyclic polyisocyanates and aliphatic polyisocyanates such as hexamethylene diisocyanate (HMDI).

[Hydroxy group-containing radical polymerizable compound]
Examples of the hydroxyl group-containing radical polymerizable compound include a hydroxyl group-containing (meth) acrylate compound and a hydroxyl group-containing (meth) acrylamide compound, which can be used alone or in combination of two or more.

Examples of the hydroxyl group-containing (meth) acrylate compound include 2-hydroxyethyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, and glycerin monomethacrylate.

Among them, the radically polymerizable urethane oligomer having a crosslinkable silicon group capped with glycerin mono (meth) acrylate is a 2-hydroxypropyl (meth) acrylate group (CH ₂ = CR ⁶ C (= O) linked by a urethane bond. _{) OCH 2 CH (OH) CH} 2 -., since ^{R 6} has) indicating a hydrogen atom or a methyl group, two polar groups ((meth) acryloyloxy groups and linked -CH ₂ groups to urethane bond) It contains a secondary hydroxyl group arranged in the portion sandwiched between the two, and can suppress polymerization inhibition by oxygen. Therefore, it is particularly preferable because oxygen inhibition is unlikely to occur and the surface curability is good.

Examples of the hydroxyl group-containing (meth) acrylamide compound include the (meth) acrylamide compound having a hydroxyl group described in JP-A-2016-113518. Specific examples of the hydroxyl group-containing (meth) acrylamide compound include 3-hydroxypropyl (meth) acrylamide, 2-hydroxyethyl (meth) acrylamide, and 4-hydroxybutyl (meth) acrylamide. Only one type of these hydroxyl group-containing (meth) acrylamide compounds may be used, or two or more types may be used in combination. Among the hydroxyl group-containing (meth) acrylamide compounds, 2-hydroxyethyl (meth) acrylamide has an extremely excellent property that the skin irritation (primary irritation index: PII) is "0" and there is no skin irritation. At the same time, it is particularly preferable because it is excellent in compatibility with various polyisocyanates and polyols.

[(Meta) acrylate containing isocyanate group]
Examples of the (meth) acrylate containing an isocyanate group include 2-isocyanatoethyl (meth) acrylate.

[Radical polymerizable urethane oligomer containing crosslinkable silicon group]
In the present invention, the radically polymerizable urethane oligomer may contain a crosslinkable silicon group. The crosslinkable silicon group is contained in the polymer of the main chain skeleton and / or at the terminal. That is, the component A can contain both a (meth) acryloyloxy group and a crosslinkable silicon group. In this case, in the composition, the crosslinkable silicon group is moisture-cured by a dark reaction after being cured by a photoreaction. As a result, it is expected that the adhesiveness due to the crosslinkable silicon group will be improved and the heat resistance will be improved by increasing the number of crosslink points.

As the position where the crosslinkable silicon group is contained, the terminal of the polymer is preferable from the viewpoint of obtaining a pressure-sensitive adhesive having sufficient flexibility. The ratio of crosslinkable silicon groups is preferably 10% or more, more preferably 20% or more, and more preferably 20% or more, based on the total number of (meth) acryloyloxy groups and crosslinkable silicon groups, from the viewpoint of improving heat resistance after moisture curing. More than a percentage is more preferable. Further, from the viewpoint of curability immediately after light irradiation, 90% or less is preferable, 80% or less is more preferable, and 70% or less is further preferable.

A radically polymerizable urethane oligomer containing a crosslinkable silicon group is an isocyanate reaction of a hydroxyl group-containing oligomer and an organic polyisocyanate with a crosslinkable silicon group such as a hydroxyl group-containing radical polymerizable compound and 3-mercaptopropyltrimethoxysilane. It can be synthesized by reacting with a compound having a sex group. It can also be synthesized by reacting a hydroxyl group-containing radical polymerizable compound with a reaction product of a hydroxyl group- and crosslinkable silicon group-containing oligomer and an organic polyisocyanate. The hydroxyl group- and crosslinkable silicon group-containing oligomer can be synthesized by reacting the hydroxyl group-containing oligomer with a crosslinkable silicon group such as 3-isocyanatepropyltrimethoxysilane and a compound having an isocyanate group.

(C component: photoinitiator)
As the photoinitiator (C), a photoradical generator, a photobase generator, a photoacid generator, or the like can be used. The photoradical generator is a compound that generates radicals by irradiation with active energy rays such as ultraviolet rays and electron beams. When the (C) photoinitiator is used as the polymerization initiator in the composition of the present invention, it can be suitably used for heat-sensitive members, and thus can be used for various purposes.

[Photo radical generator]
Examples of the photoradical generator include benzyl ketals such as 2,2-dimethoxy-1,2-diphenylethane-1-one, 2-hydroxy-2-methyl-1-phenyl-propane-1-one and the like. α-Aminoacetophenone type, 2- (dimethylamino) -2-[(4-methylphenyl) methyl] -1- [4- (4-morpholinyl) phenyl] -1-butanone and other α-aminoacetophenone type, bis (2,4,6-trimethylbenzoyl) -acylphosphine oxides such as phenylphosphine oxide, benzophenones such as methyl benzoyl benzoate, thioxanthones such as isopropylthioxanthone, 1.2-octanedione, 1- [4-( Oxime esters such as phenylthio)-, 2- (O-benzoyloxime)], titanosen such as bis (cyclopentadienyl) -bis (2,6-difluoro-3- (pyrrole-1-yl) phenyl) titanium Examples thereof include systems, benzoyl ethers, triazines, borates, carbazoles, imidazoles, etc., and derivatives obtained by increasing the molecular weight thereof.

Among these, benzyl ketal-based, α-hydroxyacetophenone-based, α-aminoacetophenone-based, acylphosphine oxide-based, oxime ester-based, and titanosen-based photopolymerization initiators are preferable because they have high sensitivity and may be added in a small amount. When a light source containing short wavelength (wavelength of 200 nm or more and 280 nm or less) such as a metal halide lamp, an electrodeless lamp (fusion lamp), or a high-pressure mercury lamp is used as a light source, the surface curability is good and oxygen inhibition occurs. From the viewpoint of difficulty, it is preferable to use a benzylketal-based or α-hydroxyacetophenone-based photoradical generator that easily reacts with short-wavelength ultraviolet rays. Further, when a light emitting diode that emits ultraviolet rays that irradiate relatively long wavelength ultraviolet rays (wavelengths exceeding 280 nm and about 450 nm or less) is used as a light source (hereinafter, the ultraviolet light emitting diode is referred to as "UV-LED"), that is, , High sensitivity to long-wavelength ultraviolet rays (i-ray (wavelength 365 nm), h-line (wavelength 405 nm), g-line (wavelength 436 nm), etc.), and the cleavage reaction proceeds sufficiently even with relatively low light energy. It is preferable to use aminoacetophenone-based, acylphosphine oxide-based, oxime ester-based, and titanosen-based photoradical initiators, and α-aminoacetophenone-based, acylphosphine oxide-based, and oxime ester-based photoradical initiators are visible light. It is most preferable because it is easy to handle because it has low sensitivity to UV rays.

In particular, as a light source, it has low power consumption and long life, does not require a duct because it does not generate ozone, has little heat damage to the adherend because it generates little heat during irradiation, and lights only during irradiation. Since it is preferable to use a UV-LED having a merit that it may be allowed to do so, photopolymerization of α-aminoacetophenone-based, acylphosphine oxide-based, oxime ester-based, and titanosen-based photopolymerization with high sensitivity to long wavelength active energy rays is started. It is preferable to use an agent. In general, when the photocurable pressure-sensitive adhesive composition is cured with a long-wavelength active energy ray, the surface curability is poorer than when the photo-curable pressure-sensitive adhesive composition is cured with a short-wavelength active energy ray. Susceptible to oxygen inhibition. However, the photocurable pressure-sensitive adhesive composition according to the present invention has good surface curability and can reduce the influence of oxygen inhibition even when it is cured by active energy rays having a long wavelength.

[Photobase generator]
Since the photobase generator also acts as a curing catalyst for the crosslinkable silicon group when irradiated with light, it is particularly effective when the radical polymerizable oligomer (B) contains the crosslinkable silicon group. The radical generated from the photobase generator has a function of curing the component A, and the base generated from the photobase generator has a function of curing a radically polymerizable urethane oligomer containing a crosslinkable silicon group.

As the photobase generator, various photobase generators can be used. A photolatent amine compound that generates an amine compound by the action of active energy rays is preferable. Examples of the photolatent amine compound include a photolatent primary amine that generates an amine compound having a primary amino group by the action of active energy rays, and an amine compound having a secondary amino group by the action of active energy rays. Both the photolatent secondary amine generated and the photolatent tertiary amine that generates an amine compound having a tertiary amino group by the action of active energy rays can be used. Photolatent tertiary amines are more preferred from the viewpoint that the generated base exhibits high catalytic activity.

Examples of the photolatent primary amine and the photolatent secondary amine include orthonitrobenzyl urethane compounds described in WO2015 / 088021; dimethoxybenzyl urethane compounds; benzoins carbamic acids; o-acyloximes. O-carbamoyloximes; N-hydroxyimide carbamates; formanilide derivatives; aromatic sulfonamides; cobaltamine complexes and the like.

Examples of the photolatent tertiary amine include α-aminoketone derivatives, α-ammonium ketone derivatives, benzylamine derivatives, benzylammonium salt derivatives, α-aminoalkene derivatives, and α-ammonium alkene derivatives described in WO2015-088021. , Amineimides, benzyloxycarbonylamine derivatives that generate amidin by light, salts of carboxylic acids and tertiary amines, and the like. Among the photobase generators, photolatent tertiary amines are preferable from the viewpoint that the generated base exhibits high catalytic activity, and benzylammonium is preferable because the base generation efficiency is high and the storage stability as a composition is good. Salt derivatives, benzyl-substituted amine derivatives, α-aminoketone derivatives and α-ammonium ketone derivatives are preferred.

When a photoinitiator is used, one type may be used alone, or two or more types may be used in combination at an arbitrary ratio. The amount of the photoinitiator added is not particularly limited, but if the amount added is small, the curing does not proceed to the deep part and curing failure may occur. Therefore, "Other (meth) excluding component A and component A" "Acrylate" (However, when other (meth) acrylates other than the A component are contained, the other (meth) acrylates excluding the A component shall contain the monomers, oligomers, and macromers of the other (meth) acrylates excluding the A component. The same applies hereinafter.) With respect to 100 parts by weight, 0.05 parts by weight or more is preferable, 0.1 parts by weight or more is more preferable, and 1 part by weight or more is further preferable. Further, if the amount of the initiator is large, the initiator may remain and adversely affect the cured physical properties. Therefore, the amount of the initiator added is 30 with respect to 100 parts by weight of the "component A and other (meth) acrylates excluding the component A". It is preferably parts by weight or less, more preferably 20 parts by weight or less, and even more preferably 10 parts by weight or less. In the present invention, the component A may not contain other (meth) acrylates other than the component A.

(When the photocurable pressure-sensitive adhesive composition contains a crosslinkable silicon group)
When the monoacrylate represented by (A) general formula (1) or general formula (2) is a compound containing a crosslinkable silicon group, the composition contains a photobase generator as a photoinitiator. Is preferable. Further, as a curing accelerator, a silicon compound having a Si—F bond can be further added. Since the component A contained in the composition has a crosslinkable silicon group, the composition can be photo-cured and then the composition can be post-cured by the moisture in the air.

As the silicon compound having a Si—F bond, various compounds including a silicon group having a Si—F bond (hereinafter, may be referred to as a fluorosilyl group) can be used. Both an inorganic compound and an organic compound can be used as the silicon compound having a Si—F bond. As the silicon compound having a Si—F bond, an organic compound having a fluorosilyl group is preferable, and an organic polymer having a fluorosilyl group is more preferable because of its high safety. Further, a low molecular weight organosilicon compound having a fluorosilyl group is preferable from the viewpoint that the composition has a low viscosity.

Examples of silicon compounds having a Si—F bond include fluorosilanes described in WO2015-088021, compounds having a fluorosilyl group described in WO2015-088021 and fluorosilyls described in WO2015-088021. Examples thereof include an organic polymer having a group.

(Component D: Adhesive-imparting resin)
The tackifier resin as the D component is not particularly limited, and for example, a resin having a polar group such as a rosin ester resin, a phenol resin, a xylene resin, a xylene phenol resin, or a terpene phenol resin, or an aromatic having a relatively small polarity. Various petroleum resins such as systems, aliphatic-aromatic copolymer systems, or alicyclic systems, or ordinary tackifier resins such as kumaron resin, low molecular weight polyethylene resin, terpene resin, and hydrogenated resins are used. be able to. These may be used alone or in combination of two or more.

Specific examples of these resins include α-methylstyrene homopolymerized resin [FTR Zero series, manufactured by Mitsui Kagaku Co., Ltd.] and styrene-based monomer monopolymerized resin [FTR 8000 series, Mitsui] as aromatic petroleum resins. Chemical Co., Ltd.], styrene monomer / aromatic monomer copolymer resin [FMR series, Mitsui Chemicals Co., Ltd.], α-methylstyrene / styrene copolymer resin [FTR 2000 series, Mitsui Chemicals Co., Ltd.] ), Etc., aromatic styrene resin. Styrene-based monomer / aliphatic monomer copolymer-based resin [FTR 6000 series, manufactured by Mitsui Kagaku Co., Ltd.], styrene-based monomer / α-methylstyrene / aliphatic monomer as an aliphatic-aromatic copolymerization system petroleum resin Examples thereof include aliphatic-aromatic copolymerized styrene resins such as copolymer resins [FTR 7000 series, manufactured by Mitsui Kagaku Co., Ltd.].

From the viewpoint of compatibility with the B component, the solubility parameter (hereinafter abbreviated as "SP value" in principle) calculated by the Small method using the Hoy constant is preferably 7.9 to 11.0, preferably 8.2 to 11.0. 9.8 is more preferable, and 8.5 to 9.5 is most preferable. From the viewpoint of the adhesive strength of the pressure-sensitive adhesive, it is preferable to select a resin having a polarity that matches the polarity of the adherend. When the tackifier resin is used for an adherend having a low polarity, it is preferable to use a tackifier resin having a low polarity, and when it is used for an adherend having a high polarity, it is preferable to use a tackifier resin having a high polarity. When the tackifier resin is used for a wide range of adherends, from highly polar adherends to low-polarity adherends, it is preferable to use a mixture of a low-polarity tackifier resin and a highly polar tackifier resin. .. The polarity (SP value) of the terpene phenol resin is 8.69 for the U series of YS Polystar (manufactured by Yasuhara Chemical Co., Ltd.), 8.81 for the T series, 8.98 for the S series, and 8.98 for the G series. Has an SP value of 9.07, and the K series has an SP value of 9.32. By selecting the polarity (SP value), it is possible to adapt to an adherend having various polarities, from an adherend having a low polarity to an adherend having a high polarity.

As the tackifier resin, a terpene phenol resin or an aromatic petroleum resin is preferable from the viewpoint of good compatibility with the B component. As the aromatic petroleum resin, an aromatic styrene resin and an aliphatic-aromatic copolymer styrene resin are preferable, and a terpenphenol resin and an aliphatic-aromatic copolymer styrene resin are more preferable. From the viewpoint of excellent adhesive strength, the terpene phenol resin is most preferable. From the viewpoint of VOC, it is preferable to use an aliphatic-aromatic copolymer styrene resin.

The blending ratio of the tackifier resin is preferably 5 to 200 parts by mass, more preferably 10 to 150 parts by mass with respect to 100 parts by mass of the A component and the B component. From the viewpoint of exerting adhesive strength, 5 parts by mass or more is preferable, and from the viewpoint of maintaining the hardness of the cured product within an appropriate range, exerting sufficient adhesive strength, and ensuring good workability, 200 parts by mass or less is preferable.

(Other additives)
The composition of the present invention contains, if necessary, a monoacrylate having a phenoxy group, a monofunctional (meth) acrylate, a polyfunctional (meth) acrylate, a vinyl compound having an amide group, a conductive filler, and an N-vinyl compound. , (Meta) acryloyl (substituted) amino group (CH ₂ = CR'C (= O) NR''-;R'represents hydrogen or methyl group, R'' represents hydrogen or alkyl group). Compounds, silane coupling agents, amino group-containing silanes, photoaminosilane generating compounds, bulking agents, plasticizers, water absorbers, condensation reaction accelerating catalysts, photosensitizers, photopolymerization accelerators, curing catalysts, tensile properties, etc. Improve physical properties modifiers, reinforcing agents, colorants, flame retardants, anti-sags, antioxidants, anti-aging agents, UV absorbers, solvents, fragrances, pigments, dyes, fillers, diluents, polymerization inhibitors, solid polymers Various additives such as the above may be added.

(Monoacrylate having a phenoxy group)
The composition of the present invention may contain a monoacrylate having a phenoxy group having a hardness higher than that of the component (A). Examples of the monoacrylate having a phenoxy group include substituted or unsubstituted 3-phenoxy-2-hydroxypropyl (meth) acrylate represented by the following general formula (4).

In the general formula (4), R ¹ represents −H or −CH ₃ , and R ^{7 to} R ¹¹ are independently hydrogen atoms or substituents. Examples of the substituent include a nitro group, a cyano group, a hydroxy group, a halogen atom, an acetyl group, a carbonyl group, a substituted or unsubstituted allyl group, and a substituted or unsubstituted alkyl group (preferably having 1 to 5 carbon atoms). Alkyl group), substituted or unsubstituted alkoxy group (preferably alkoxy group having 1 to 5 carbon atoms), unsubstituted or substituted aryl group, unsubstituted or substituted aryloxy group, heterocyclic structure-containing group, multiple rings. Examples thereof include a group having a group and a combination thereof. Any of R ^{7 to} R ¹¹ may be bonded to each other to form a cyclic structure. When at least two groups selected from the group consisting of R ^{7 to} R ¹¹ are bonded to each other to form a cyclic structure, a structure in which a plurality of benzene rings are condensed, a benzene ring and a heterocyclic ring or a non-aromatic ring, A structure or the like in which a ring or the like to which a functional group such as a carbonyl group is bonded may be condensed may be formed. Among these substituents, a substituted or unsubstituted alkyl group is preferable, and a substituted or unsubstituted alkyl group having 1 to 5 carbon atoms is more preferable.

Monoacrylate having a phenoxy group of the general formula (4) includes a secondary hydroxyl group which is arranged in a portion sandwiched between two -CH ₂ groups, and an electron attractive group (the phenoxy group located at both ends of the molecule (meth ) Acryloyloxy group), and like the monoacrylate of the component (A), it can suppress polymerization inhibition by oxygen. Specific examples include 2-hydroxy-3-phenoxypropyl acrylate and the like.

(Monofunctional (meth) acrylate)
As the monofunctional (meth) acrylate, a monofunctional (meth) acrylate having a number average molecular weight of 1,000 or less can be used. As for the monofunctional (meth) acrylate, the T _{g of the} homopolymer obtained from the monofunctional (meth) acrylate is preferably 40 ° C. or lower, more preferably 10 ° C. or lower, and most preferably 0 ° C. or lower. From the viewpoint of ease of blending, it is preferable that the liquid is liquid at 20 ° C.

As a monofunctional (meth) acrylate, for example,
CH ₂ = CR ^α COO ( _Cm H _2m O) _n R ^β ... (5)
(In general formula (5), R ^α is −H or −CH ₃ , m is an integer of 2 to 4, n is an integer of 1 to 20, and R ^β is −H or an unsubstituted or substituted alkyl group. It indicates an unsubstituted or substituted phenyl group.). Specifically, as the monofunctional (meth) acrylate, a compound having R ^β in H in the general formula (5), a (meth) acrylate having a hydroxyl group such as an aliphatic epoxy (meth) acrylate; R ^{β in the} general formula (5). Is a (meth) acrylate having an alkoxy group such as an unsubstituted or substituted alkyl group compound; an aromatic such as an aryl (meth) acrylate or a phenyl group compound in which R ^β is unsubstituted or substituted in the general formula (5). Meta) acrylate; Long-chain hydrocarbon-based (meth) acrylate having 8 to 20 carbon atoms; Aliphatic (meth) acrylate; (meth) acrylate having a heterocyclic group; (meth) acrylate having an alkoxysilyl group, etc. Can be mentioned. A long-chain hydrocarbon-based (meth) acrylate having 8 to 20 carbon atoms and / or a compound of the general formula (5) is preferable in that the pressure-sensitive adhesive has excellent adhesiveness, and has a length of 8 to 20 carbon atoms. Chain hydrocarbon-based (meth) acrylates, (meth) acrylates having a hydroxyl group, and (meth) acrylates having an alkoxy group are more preferable, and long-chain hydrocarbon-based (meth) acrylates having 8 to 20 carbon atoms are most preferable.

Specific examples of the monofunctional (meth) acrylate are as follows. First, examples of the long-chain hydrocarbon-based (meth) acrylate having 8 to 20 carbon atoms include 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, lauryl (meth) acrylate, and isostearyl (meth) acrylate. Can be mentioned.

Examples of the alicyclic (meth) acrylate include isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate, and dicyclopentenyloxyethyl (meth) acrylate.

Examples of the (meth) acrylate having a hydroxyl group include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, cyclohexanedimethanol mono (meth) acrylate, and glycerol mono. Hydroxyalkyl (meth) acrylates such as (meth) acrylates; Polyalkylene glycol mono (meth) acrylates such as polyethylene glycol mono (meth) acrylates, polypropylene glycol mono (meth) acrylates, and polyethylene glycol-polypropylene glycol copolymers. Can be mentioned.

Aromatic (meth) acrylates include benzyl (meth) acrylate, phenolalkylene oxide-modified (meth) acrylate, alkylphenolalkylene oxide-modified (meth) acrylate, p-cumylphenolalkylene oxide-modified (meth) acrylate, and o-phenyl. Examples thereof include phenol alkylene oxide-modified (meth) acrylate. Examples of the alkylene oxide include ethylene oxide and propylene oxide.

Examples of the (meth) acrylate having an alkoxy group include alkoxypolyethylene glycol mono (meth) acrylate such as ethoxydiethylene glycol (meth) acrylate; alkoxypolypropylene glycol mono (meth) acrylate such as methoxytripropylene glycol (meth) acrylate; and alkoxypolyethylene glycol. -Polypropylene glycol copolymer and the like can be mentioned.

Examples of the (meth) acrylate having a carboxyl group include (meth) acrylic acid, a polycaprolactone modified product of (meth) acrylic acid, a Michael addition multimer of (meth) acrylic acid, and 2-hydroxyethyl (meth) acrylate and anhydrous. Examples thereof include additions of phthalic acid, additions of 2-hydroxyethyl (meth) acrylate and succinic anhydride.

Examples of the (meth) acrylate having a heterocyclic group include tetrahydrofurfuryl (meth) acrylate and N- (meth) acryloyloxyethyl hexahydrophthalimide, and examples of the (meth) acrylate having an amino group include N and N. -Dimethylaminoethyl acrylate and the like can be mentioned.

Examples of the (meth) acrylate having an alkoxysilyl group include 3- (trimethoxysilyl) propyl (meth) acrylate, and examples of the (meth) acrylate having an epoxy group include glycidyl (meth) acrylate and cyclohexene oxide. Examples thereof include (meth) acrylate, and examples of the (meth) acrylate having a phosphate group include 2- (meth) acryloyloxyethyl acid phosphate and the like. Further, (meth) acrylate having a fluoroalkyl group, (meth) acrylate having a tribromophenyl group and the like can be mentioned.

(Polyfunctional (meth) acrylate)
Examples of the polyfunctional (meth) acrylate having two or more (meth) acryloyl groups include 1,6-hexadiol di (meth) acrylate, neopentyl glycol di (meth) acrylate, and dicyclopentanyl di (meth) acrylate. , Polypropylene glycol di (meth) acrylate, 2,2-bis (4- (meth) acryloxidiethoxyphenyl) propane, or 2,2-bis (4- (meth) acryloxitetraethoxyphenyl) propane, etc. 2 Functional (meth) acrylate, trimethylolpropane tri (meth) acrylate, trifunctional (meth) acrylate such as tris [(meth) acryloixethyl] isocyanurate, dimethylolpropanetetra (meth) acrylate, pentaerythritol tetra (meth) ) Acrylate, or tetrafunctional or higher functional (meth) acrylate such as pentaerythritol ethoxytetra (meth) acrylate can be mentioned.

The molecular weight of the polyfunctional (meth) acrylate is less than 1,000. The blending ratio of the polyfunctional (meth) acrylate is 10 with respect to 100 parts by mass of the A component (or the total of the A component and the monoacrylate having a phenoxy group) from the viewpoint of exerting the effect of suppressing oxygen inhibition by the A component. It is preferably parts by mass or less, more preferably 5 parts by mass or less, and most preferably 2 parts by mass or less. From the viewpoint of ensuring sufficient cohesive force under high temperature conditions, 0.01 part by mass or more is preferable, 0.05 part by mass or more is more preferable, and 0.1 part by mass or more is most preferable.

When a vinyl compound having an amide group or an N-vinyl compound is used, the cohesive force of the pressure-sensitive adhesive can be further improved and the adhesiveness can be further improved. In the present invention, vinyl compounds and N-vinyl compounds having an amide group are preferable from the viewpoint of reactivity and the fact that oxygen inhibition is unlikely to occur.

(Vinyl compound having an amide group)
Examples of the vinyl compound having an amide group include N-vinyl cyclic amides such as N-vinyl-2-pyrrolidone and N-vinyl-2-caprolactam; N, N-diethyl (meth) acrylamide and N- (2-hydroxyethyl). ) Acrylamides such as (meth) acrylic loylmorpholine and the like. Acryloyl morpholine is preferable because it has a good balance of curability, physical properties and safety.

(N-vinyl compound)
Examples of the N-vinyl compound include N-vinylpyrrolidone, N-vinylcaprolactam, N-vinylacetamide and the like. N-vinylpyrrolidone is preferable because it has a good balance between curability and physical properties.

(Silane coupling agent)
The silane coupling agent acts as an adhesive imparting agent. Examples of the silane coupling agent include epoxy group-containing silanes such as γ-glycidoxypropyltrimethoxysilane and β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane; γ-aminopropyltrimethoxysilane, N. Amino group-containing silanes such as-(β-aminoethyl) -γ-aminopropyltrimethoxysilane; ketimine such as N- (1,3-dimethylbutylidene) -3- (triethoxysilyl) -1-propaneamine Type silanes; mercapto group-containing silanes such as γ-mercaptopropyltrimethoxysilane; vinyl unsaturated group-containing silanes such as vinyltrimethoxysilane and γ-methacryloyloxypropyltrimethoxysilane; γ-chloropropyltrimethoxysilane Chlorine atom-containing silanes such as γ-isocyanide propyltriethoxysilane and the like; alkylsilanes such as decyltrimethoxysilane; phenyl group-containing silanes such as phenyltrimethoxysilane and the like. It is not limited to. Further, a modified amino group-containing silane in which an amino group is modified by reacting an amino group-containing silane with an epoxy group-containing compound containing the above silanes, an isocyanate group-containing compound, or a (meth) acryloyl group-containing compound is used. You may.

(Amino group-containing silanes)
Amino group-containing silanes act as silanol condensation catalysts. In addition, ketimine-type silanes generate amino group-containing silanes in the presence of water and act as a silanol condensation catalyst. Therefore, it is preferable to use a silane coupling agent other than amino group-containing silanes and ketimine-type silanes. When amino group-containing silanes and ketimine-type silanes are used, their types and / or amounts used are adjusted within the range in which the object and effect of the present invention are achieved.

(Optical aminosilane generating compound)
As described above, the use of amino group-containing silanes and ketimine-type silanes may be restricted in the present invention. However, when it is desirable to use amino group-containing silanes or ketimine-type silanes as an adhesive-imparting agent, a compound having an amino group is not generated before light irradiation, and amino group-containing silanes are obtained by light irradiation. A compound that generates (hereinafter, also referred to as a photoaminosilane generating compound) can be used. As the photoaminosilane generating compound, the photofunctional group described in WO2015 / 088021 is represented by an o-nitrobenzyl group, a p-nitrobenzyl group, an oxime residue, a benzyl group, a benzoyl group, a substituted group thereof, or the like. Some compounds are mentioned. Examples of the photoaminosilane generating compound in which the photofunctional group is an o-nitrobenzyl group include 2-nitrobenzyl-N- [3- (trimethoxysilyl) propyl] carbamate and 2-nitrobenzyl-N- [3- (triethoxy). Examples thereof include silyl) propyl] carbamate and 3,4-dimethoxy-2-nitrobenzyl-N- [3- (trimethoxysilyl) propyl] carbamate. Examples of the photoaminosilane generating compound in which the photofunctional group is a p-nitrobenzyl group include 4-nitrobenzyl-N- [3- (trimethoxysilyl) propyl] carbamate. Examples of the photoaminosilane generating compound in which the photofunctional group is a benzyl group include 1- (3,5-dimethoxyphenyl) -1-methylethyl-N- [3- (trimethoxysilyl) propyl] carbamate. Examples of the photoaminosilane generating compound in which the photofunctional group is an oxime residue group include benzophenone O-{[3- (trimethoxysilyl) propyl]} oxime.

The blending ratio of the silane coupling agent is not particularly limited, but is preferably 0.01 to 20% by mass, more preferably 0.025 to 10% by mass in the composition. These silane coupling agents can be used alone or in combination of two or more.

(Moist absorber)
As the water absorbent, it is preferable to use the above-mentioned silane coupling agent or silicate. The silicate is not particularly limited, and examples thereof include tetramethoxysilane, tetraalkoxysilane, and a partially hydrolyzed condensate thereof.

(Condensation reaction acceleration catalyst)
As a catalyst for promoting the condensation reaction of a crosslinkable silicon group other than the C component and a compound having a Si—F bond, a known curing catalyst can be widely used, and there is no particular limitation, but for example, an organic metal compound or an amine. Kind, fatty acids, organic acidic phosphoric acid ester compounds and the like, and it is particularly preferable to use a silanol condensation catalyst. Examples of the silanol condensation catalyst include organic tin compounds; dialkyl tin oxides; reactants of dibutyl tin oxide and phthalates; titanic acid esters; organoaluminum compounds; chelate compounds such as titanium tetraacetylacetonate; Examples include bismuth organic acid. However, depending on the amount of the organic tin compound added, the toxicity of the obtained composition may become stronger. Since the C component of the present invention and the compound having a Si—F bond act as a condensation reaction promoting catalyst, when a curing catalyst other than these is used, the condensation reaction of the crosslinkable silicon group may proceed regardless of light irradiation. Therefore, it is preferable to use it within a range in which the object and effect of the present invention can be achieved.

(Photosensitizer)
As the photosensitizer, a carbonyl compound having a triplet energy of 225-310 kJ / mol is preferable, for example, a thioxanthone such as isopropylthioxanthone and a derivative thereof, a dialkoxyanthracene derivative such as 9,10-dibutoxyanthracene, 2-. Examples thereof include benzophenone and its derivatives such as methyl benzoylbenzoate, coumarin derivatives such as 3-acylcoumarin and 3,3'-carbonylbiscoumarin, and thioxanthone and its derivatives and coumarin derivatives are preferable, and thioxanthone and its derivatives and benzophenone and the like. The derivative and the carbonyl derivative are more preferable.

The blending ratio of the photosensitizer is not particularly limited, but is preferably 0.01 to 5% by mass, more preferably 0.025 to 2% by mass in the composition. These photosensitizers may be used alone or in combination of two or more.

(Photopolymerization accelerator)
A photopolymerization accelerator can be used in combination with the initiator for the purpose of accelerating the curing reaction by the photopolymerization initiator. Examples of the photopolymerization accelerator include tertiary amines such as triethylamine, triethanolamine and 2-dimethylaminoethanol; arylphosphines such as triphenylphosphine, arylphosphine oxides such as triphenylphosphine oxide, and triphenylphosphine. Aryl phosphates such as, phosphines including aryl phosphates such as triphenyl phosphate (aryl groups may have substitutions); thiols typified by β-thioglycol and the like can be mentioned. Preferred phosphines are trifunctional phosphine derivatives, more preferably triarylphosphine and most preferably triphenylphosphine.

(Filler)
As the filler, a resin filler (resin fine powder), an inorganic filler, and a functional filler can be used. The filler may be surface-treated with a silane coupling agent, a titanium chelating agent, an aluminum coupling agent, a fatty acid, a fatty acid ester, rosin or the like. As the resin filler, a particulate filler made of an organic resin or the like can be used. For example, as the resin filler, organic fine particles such as ethyl polyacrylate resin, polyurethane resin, polyethylene resin, polypropylene resin, urea resin, melamine resin, benzoguanamine resin, phenol resin, acrylic resin, and styrene resin can be used. When used in applications where light-shielding properties are required, such as in the peripheral portion of a liquid crystal display device, the resin filler may contain a black resin filler. Even when a long-wavelength LED lamp or the like is used, good deep curability can be obtained, and excellent light-shielding property and deep curability can be achieved.

Examples of the inorganic filler include talc, clay, calcium carbonate, magnesium carbonate, silicon anhydride, hydrous silicon, calcium silicate, titanium dioxide, titanium black, carbon black and the like.

Examples of the functional filler include conductive fillers described in JP-A-2013-14734, JP-A-2017-2267, JP-A-2011-50801, etc .; and excellent in heat insulating properties, lightness and the like described in JP-A-2016-199668, etc. Hollow particles; core-shell particles having excellent sound insulation and vibration damping properties described in JP-A-2016-199669 and the like; layered silicates having excellent gas barriers and the like described in JP-A-2016-199670; The light-reflecting filler described; the electromagnetic wave shielding material described in JP-A-2016-199750 and the like can be used.

(Diluent)
In the present invention, a solvent having a flash point (open type) of 50 ° C. or higher is used as the diluent. By containing a diluent, physical properties such as viscosity can be adjusted. As the diluent, various diluents can be used. Examples of the diluent include saturated hydrocarbon solvents such as normal paraffin and isoparaffin, α-olefin derivatives such as linearene dimer (trade name of Idemitsu Kosan Co., Ltd.), aromatic hydrocarbon solvents, alcohol solvents, and ester solvents. Examples thereof include a solvent, a citrate ester solvent such as acetyltriethyl citrate, and various solvents such as a ketone solvent.

When considering the safety of the obtained composition, it is desirable that the composition has a high flash point, and it is preferable that the amount of volatile substances from the composition is small. Therefore, the flash point of the diluent is preferably 60 ° C. or higher, more preferably 70 ° C. or higher. However, in general, a diluent having a high flash point tends to have a low diluting effect on the composition, so it is preferable to use a diluent having a flash point of 250 ° C. or lower. When two or more kinds of diluents are mixed, the flash point of the mixed solution is the above-mentioned flash point.

When both the safety of the composition and the diluting effect are taken into consideration, the saturated hydrocarbon solvent is preferable as the diluent, and normal paraffin and isoparaffin are more preferable. The carbon number of normal paraffin and isoparaffin is preferably 10 to 16.

The mixing ratio of the diluent is preferably in the range of 0 to 50 parts by mass with respect to 100 parts by mass of the A component or 100 parts by mass of the other (meth) acrylate excluding the A component and the A component. It is more preferably blended in the range of 1 to 30 parts by mass, and further preferably blended in the range of 0.1 to 15 parts by mass. The diluent may be used alone or in combination of two or more.

The content of the liquid medium (volatile solvent, water) with respect to the entire composition is preferably 5% by weight or less, more preferably 3% by weight or less, still more preferably 1% by weight or less, and the liquid medium. A composition that does not substantially contain (that is, a composition that is substantially solvent-free) is most preferable. Here, "substantially free of liquid medium" means that the composition does not contain any liquid medium, or the content thereof is 0.1% by mass or less of the composition. Here, a solvent having a flash point of 50 ° C. or lower is used as a volatile solvent. For example, in the form of a composition containing a liquid medium, it is preferable to irradiate the composition with active energy rays after drying the composition applied to the support.

(Polymerization inhibitor)
The polymerization inhibitor is not particularly limited, but for example, a radical scavenger such as hindered phenol and hindered amine, a phosphorus-based secondary oxidative deterioration inhibitor, diethylhydroxylamine, sulfur, t-butylcatechol, potassium triiodide, and the like. Examples thereof include N-nitrosophenylhydroxylamine aluminum salt. The polymerization inhibitor may be used alone or in combination of two or more.

(Solid polymer)
As the solid polymer, a solid polymer at 20 ° C. can be used. Examples of the solid polymer include a homopolymer obtained by polymerizing one of the various monomers alone, and a copolymer (random polymer or block polymer) obtained by copolymerizing two or more of them.

As the copolymer, a block polymer having a hard polymer block A having a glass transition temperature of 0 ° C. or higher, preferably 30 ° C. or higher and a soft polymer block B having a glass transition temperature of less than 0 ° C., preferably -10 ° C. or lower is used. Is preferable.

Examples of the block polymer of the hard polymer block A and the soft polymer block B include a non-acrylic block copolymer composed of a styrene-based polymer block A and a conjugated diene-based polymer or a polymer block B composed of a hydrogenated product thereof. .. Specific examples thereof include block copolymers of styrene and conjugated diene such as butadiene and isoprene, or hydrogenated products thereof.

The block polymer is described in JP-A-2003-277521, which comprises a hard polymer block A such as styrene or a derivative thereof and methyl methacrylate and an acrylic polymer block B such as butyl acrylate and 2-ethylhexyl acrylate. Acrylic block copolymer is particularly preferable.

As the acrylic block copolymer, a triblock copolymer of polymethylmethacrylate-polyn-butylacrylate-polymethylmethacrylate is preferable from the viewpoint of solubility, adhesiveness, and transparency.

(Manufacturing method of photocurable pressure-sensitive adhesive composition)
The method for producing the photocurable pressure-sensitive adhesive composition is not particularly limited. For example, a predetermined amount of A component, B component, and C component is blended, and if necessary, another blended substance is blended to degas. It can be manufactured by stirring. The blending order of each component and other compounding substances is not particularly limited and can be appropriately determined.

The photocurable pressure-sensitive adhesive composition according to the present invention may be a one-component type or a two-component type, if necessary, but is particularly preferably used as a one-component type. The photocurable pressure-sensitive adhesive composition according to the present invention is a composition that exhibits adhesiveness and is cured by light irradiation, and can be cured at room temperature (for example, 23 ° C.), and is a room temperature photocurable pressure-sensitive adhesive. However, if necessary, curing may be promoted by heating as appropriate.

The photocurable pressure-sensitive adhesive composition according to the present invention exhibits adhesiveness and cures when irradiated with light. A pressure-sensitive adhesive can be obtained by this curing. Further, using the photocurable pressure-sensitive adhesive composition according to the present invention, various pressure-sensitive adhesive-containing products such as electronic circuits, electronic parts, building materials, and automobiles can be manufactured.

The conditions for irradiating the photocurable pressure-sensitive adhesive composition according to the present invention with light are not particularly limited, but when the photocurable pressure-sensitive adhesive composition is irradiated with active energy rays during curing, the active energy rays may be cured by ultraviolet rays or visible light. Available. The ultraviolet rays include g-line (wavelength 436 nm), h-line (wavelength 405 nm), i-line (wavelength 365 nm) and the like. The active energy radiation source is not particularly limited, but can be appropriately selected depending on the reaction wavelength of the photoinitiator to be used. For example, as a light source, a metal halide lamp, a high power metal halide lamp (containing indium, etc.), an electrodeless lamp (fusion lamp), a low pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a mercury-xenon lamp, an argon laser, etc. Examples thereof include xenon lamps, xenon flash lamps, and LEDs.

Each of these light sources has a different radiation wavelength and energy distribution. Therefore, it is preferable to select these light sources according to the reaction wavelength of the photoinitiator and the like. Further, a xenon-flash lamp or LED capable of intermittently irradiating active energy rays is preferable because the influence of heat on the adherend can be minimized. In particular, UV-LEDs, which have advantages such as low power consumption and long life, are more preferable because they have lower radiant heat than other ultraviolet lamps, are small in size, and have a high degree of freedom in designing a light irradiation device. The emission wavelength of the UV-LED can be selected depending on the combination with the photopolymerization initiator, but is preferably 280 nm or more and 450 nm or less, more preferably 300 nm or more and 450 nm or less, and further preferably 350 nm or more and 450 nm or less. Further, the LED has the above-mentioned merits, and since a plurality of LEDs having different emission wavelengths can be combined with each other, the UV-LED is the most preferable as the light source.

The irradiation energy, for example, in the case of UV, preferably 10~20,000mJ / cm ^2, more preferably ^{20~10,000mJ / cm 2, 50~5,000mJ / cm} 2 is more preferable. If it is less than 10 mJ / cm ² , the curability may be insufficient, and if it is larger than 20,000 mJ / cm ² , time and cost will be wasted even if the light is irradiated more than necessary, and the base material will be damaged. There is.

The method for applying the photocurable pressure-sensitive adhesive composition according to the present invention to an adherend is not particularly limited, but application methods such as screen printing, stencil printing, roll printing, dispenser coating, and spin coating are preferably used.

Further, there is no limitation on the timing of application of the photocurable pressure-sensitive adhesive composition to the adherend and light irradiation. For example, the photocurable pressure-sensitive adhesive composition is irradiated with light and then bonded to an adherend to produce a product (that is, an adhesive). Further, the photocurable pressure-sensitive adhesive composition can be applied to an adherend and irradiated with light to cure the photo-curable pressure-sensitive adhesive composition to produce a product.

Further, for example, when the adherends are bonded to each other, the photocurable pressure-sensitive adhesive composition according to the present invention is applied to at least one adherend (coating step). In the coating step, the photocurable pressure-sensitive adhesive composition may be applied to one of the adherends, or the photo-curable pressure-sensitive adhesive composition may be applied to each of both adherends. From the viewpoint of simplifying the coating process, the photocurable pressure-sensitive adhesive composition can be applied to only one of the adherends. Next, the photocurable pressure-sensitive adhesive composition is irradiated with light (light irradiation step). The photocurable pressure-sensitive adhesive composition exhibits adhesiveness when irradiated with light. Subsequently, after light irradiation, the other adherend is brought into contact with the photocurable pressure-sensitive adhesive composition which is applied to one adherend and irradiated with light. That is, by sandwiching the photocurable pressure-sensitive adhesive composition applied to one adherend between the other adherends, the other adherend is bonded to one adherend (bonding step). Then, the other adherend is adhered to one adherend (adhesion step). As a result, a product (that is, an adhesive body) in which the adherends are adhered to each other is manufactured. However, as the other adherend, a protective member such as a protective sheet for the adhesive surface is excluded. This is because the photocurable pressure-sensitive adhesive composition used in the bonding method of the present invention is suitable for on-site construction, and one adherend and the other adherend are directly bonded by the photo-curable pressure-sensitive adhesive composition. Because it is done.

The photocurable pressure-sensitive adhesive composition according to the present invention is a fast-curing composition having excellent workability, and the cured product can be suitably used as a pressure-sensitive adhesive.

(Effect of embodiment)
Since the photocurable pressure-sensitive adhesive composition according to the present invention is liquid before light irradiation, it can be applied directly to an adherend, and can be easily applied to an adherend having a complicated shape. Then, the photocurable pressure-sensitive adhesive composition quickly exhibits adhesiveness by light irradiation without blocking from the outside air. Therefore, according to the photocurable pressure-sensitive adhesive composition according to the present invention, the photo-curable pressure-sensitive adhesive composition exhibits adhesiveness after the photo-curable pressure-sensitive adhesive composition is applied to one of the adherends and irradiated with light. Since the other adherend can be attached to the sheet, a plurality of adherends can be easily attached to each other even when the adherend does not transmit light such as ultraviolet light.

That is, the photocurable pressure-sensitive adhesive composition according to the present invention does not cure when not irradiated with active energy rays, does not block from the outside air, and even in the presence of oxygen (that is, even if it is not covered with a film or the like). It is a composition that is cured by irradiation with active energy rays, and has a fast-curing property having excellent rising adhesiveness after irradiation with active energy rays. Therefore, it is possible to secure a predetermined bonding time after light irradiation. Further, in the present invention, a UV-LED can be used as a light source, and in this case, damage to the adherend can be reduced.

An embodiment will be described below in more detail. Needless to say, these examples are examples and should not be construed in a limited manner.

(Synthesis Example 1: Synthesis of C12MAc)
C12, 13 mixed alcohol glycidyl ether and acrylic acid were synthesized at a ratio of 1 mol: 2 mol according to Example 1 of JP2013-82895A. To remove excess acrylic acid, 2-hydroxy-3-acryloyloxy propyl C12-13 mixed alcohol ethers with _{(C n H 2n OCH 2 CH} (OH) CH 2 OC (= O) CH = CH 2 C12MAc liquid at room temperature was obtained with n = 12, 13) as the main component. As a result of IR spectrum measurement of this compound, it was confirmed that the absorption of −OH expansion and contraction derived from carboxylic acid disappeared. In addition, it was confirmed that a -OH expansion and contraction peak due to glycidyl group ring opening occurred.

During the above synthesis reaction, the epoxy group of the C12, 13 mixed alcohol glycidyl ether is ring-opened to form an ester bond with acrylic acid. This ring-opening occurs at either the α-position or the β-position, but the α-adduct opened at the α-position is the main component and the β-adduct opened at the β-position is the sub-component. Usually, the production ratio of the α adduct and the β adduct is 100 / 0.01 to 100/70 in molar ratio, preferably 100 / 0.1 to 100/50. In Synthesis Example 1, a product having a compound which is usually an α adduct as a main component and a β adduct as a sub component can be obtained. When the α adduct, which is the main component, is isolated, it can be isolated by separating the product by a known separation method. In Synthesis Example 1, a mixture containing an α adduct and a β adduct is obtained as a monoacrylate of component A. That is, the product obtained in Synthesis Example 1 is a composition in which all or a part of the β adduct is left in the product obtained by the above synthesis method, and the α adduct is the main component. Here, the "main component" refers to a component containing 60 mol% or more in the product, and the "sub-component" refers to a component containing 40 mol% or less.

Here, 5 g of Irgacure TPO (2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide manufactured by BASF) was added to 100 g of C12MAc synthesized in Synthesis Example 1, and the mixture was mixed and stirred to prepare a photocurable composition. Prepared. A surface curability test of this composition (see the "Surface Curability Test" section below for test conditions) and a hardness test (see the "Hardness Test" section below for test conditions) were carried out. As a result, the result of the surface curability test was "◯", and the result of the hardness test was 30.

Then, for comparison, 5 g of Irgacure TPO was added to 100 g of LA (lauryl acrylate; a long-chain hydrocarbon acrylate having 12 carbon atoms), and the mixture was mixed and stirred to prepare a photocurable composition (comparative composition 1). .. Similarly, for comparison, 5 g of Irgacure TPO was added to ACMO (4-acryloyl morpholine; a vinyl compound having an amide group), and the mixture was mixed and stirred to prepare a photocurable composition (comparative composition 2). As a result of carrying out the surface curability test and the hardness test of the comparative composition 1 in the same manner as above, the result of the surface curability test was "x", and the result of the hardness test was poor in curability and could not be measured. It was. Further, as a result of conducting the surface curability test and the hardness test of the comparative composition 2 in the same manner, the result of the surface curability test was "○", but the result of the hardness test exceeded the measurement upper limit of 95. It was shown to be a hard cured product. In addition, 5 g of Irgacure TPO was added to 100 g of HPPA (2-hydroxy-3-phenoxypropyl acrylate), and the mixture was mixed and stirred to prepare a photocurable composition (comparative composition 3). As a result of conducting the surface curability test and the hardness test of the comparative composition 3 in the same manner, the result of the surface curability test was "◯" and the result of the hardness test was 82.

(Synthesis Example 2: Synthesis of GMADAc)
Triphenylphosphine 0.074 g (0.28 mmol) using 4.00 g (28.1 mmol; product name "Light Ester G", manufactured by Kyoeisha Scientific Co., Ltd.) and 4.85 g (28.1 mmol) of decanoic acid as catalysts. ) Was added, and the mixture was reacted at 60 ° C. for 24 hours. A light brown compound (GMADAc) containing 2-hydroxy-3-decanoyloxypropyl methacrylate as a main component was obtained. As a result of IR spectrum measurement of the compound, it was confirmed that the absorption of -OH expansion and contraction derived from the carboxylic acid disappeared. In addition, it was confirmed that a -OH expansion and contraction peak due to glycidyl group ring opening occurred.

In addition, 10 g of Irgacure TPO was added to 100 g of GMADAc synthesized in Synthesis Example 2 and mixed and stirred to prepare a photocurable composition. A surface curability test of this composition (see the "Surface Curability Test" section below for test conditions) and a hardness test (see the "Hardness Test" section below for test conditions) were carried out. As a result, the result of the surface curability test was "◯", and the result of the hardness test was 33.

(Synthesis Example 3: Synthesis of Urethane Acrylate (DL-10000-1))
Urethane prepolymer of PPG skeleton at both ends of isocyanate group obtained by reacting 100 g of PPG (polypropylene glycol, Mw / Mn = 1.1, number average molecular weight: 10,000) with 4.0 g of xylylene diisocyanate (XDI). To 104.0 g of (PU-PPG10000), 3.9 g of glycerin monomethocyanate and 0.05 g of a polymerization inhibitor (hydroquinone) were added and reacted at 70 ° C. for 24 hours. The number average molecular weight was 32,000, and the mixture was liquid at room temperature. A urethane acrylate (DL-10000-1) having a PPG skeleton at both ends of a 2-hydroxypropyl methacrylate group was obtained. As a result of IR spectrum measurement, it was confirmed that the absorption of −NCO derived from the isocyanate group disappeared and the absorption of −OH expansion and contraction derived from the hydroxyl group remained. The number average molecular weight is a polystyrene-equivalent molecular weight measured by gel permeation chromatography using HLC-8120GPC manufactured by Tosoh as a liquid feeding system, TSK-GELH type manufactured by Tosoh as a column, and THF as a solvent.

(Synthesis Example 4: Synthesis of Urethane Acrylate (DL-10000-2))
Urethane prepolymer of PPG skeleton at both ends of isocyanate group obtained by reacting 100 g of PPG (polypropylene glycol, Mw / Mn = 1.1, number average molecular weight: 10,000) with 4.0 g of xylylene diisocyanate (XDI). To 104.0 g of (PU-PPG10000), 2.6 g of HEAA (hydroxyethyl acrylamide) and 0.05 g of a polymerization inhibitor (hydroquinone) were added and reacted at 70 ° C. for 24 hours, and the number average molecular weight was 44,000. Urethane acrylate (DL-10000-2) having a PPG skeleton at both ends of the acryloylaminoethyl group, which is liquid at room temperature, was obtained. As a result of IR spectrum measurement, it was confirmed that the absorption of -NCO derived from the isocyanate group had disappeared.

(Synthesis Example 5: Synthesis of Urethane Acrylate (T6000))
Urethane prepolymer of PPT skeleton at both ends of isocyanate group obtained by reacting 100 g of PPT (polypropylene triol, Mw / Mn = 1.1, number average molecular weight: 6,000) with 9.9 g of xylylene diisocyanate (XDI). To 109.9 g of (PU-PPT6000), 9.7 g of glycerin monomethocyanate and 0.05 g of a polymerization inhibitor (hydroquinone) were added and reacted at 70 ° C. for 24 hours. The number average molecular weight was 19,000, and the mixture was liquid at room temperature. A urethane acrylate (T6000) having a PPT skeleton at both ends of the 2-hydroxypropyl methacrylate group was obtained. As a result of IR spectrum measurement, it was confirmed that the absorption of −NCO derived from the isocyanate group disappeared and the absorption of −OH expansion and contraction derived from the hydroxyl group remained.

(Synthesis Example 6: Synthesis of Urethane Acrylate (BO-3U))
Hydroxyl-containing oligomer (PBA1; number average molecular weight 10,000, primary and secondary hydroxyl groups at one end) of n-butyl (BA) acrylate skeleton obtained by reaction using thioglycerol described in JP-A-2000-128911. (1 each is present.) Glycerin monomethacrylate was obtained by reacting 100 g with 3.8 g of xylylene diisocyanate (XDI) and obtained by reacting 103.8 g of a urethane prepolymer (PU-BA) having a BA skeleton at both ends of the isocyanate group. 3.7 g and 0.05 g of a polymerization inhibitor (hydroquinone) were added and reacted at 70 ° C. for 24 hours. A 2-hydroxypropyl methacrylate group having a number average molecular weight of 22,000 and being liquid at room temperature was added to one end. Two BA skeleton urethane acrylates (BO-3U) were obtained. As a result of IR spectrum measurement, it was confirmed that the absorption of −NCO derived from the isocyanate group disappeared and the absorption of −OH expansion and contraction derived from the hydroxyl group remained.

(Example 1)
Each compounding substance is added to a flask equipped with a stirrer, a thermometer, a nitrogen inlet, a monomer charging tube, and a water-cooled condenser at the compounding ratios shown in Table 1, and the mixture is mixed and stirred to photo-cure according to Example 1. A sex pressure-sensitive adhesive composition was prepared.

In Table 1, the unit of the compounding amount of each compounding substance is "g". The details of the compounded substances are as follows. As the component A, the compounds synthesized in Synthesis Examples 1 and 2 were used.
(A'component: monofunctional (meth) acrylate)
ACMO (ACMO; manufactured by Osaka Organic Chemical Industry Co., Ltd., 4-acryloyl morpholine)
HPPA (Aronix M-5700; manufactured by Toagosei Co., Ltd., 2-hydroxy-3-phenoxypropyl acrylate)
LA (Light Acrylate LA; Lauryl Acrylate, manufactured by Kyoeisha Chemical Co., Ltd.)
(B component: radically polymerizable oligomer)
For DL-10000-1, DL-10000-2, T6000, and BO-3U, the compounds synthesized in Synthesis Examples 3 to 6 were used, respectively.
(C component: photoinitiator)
IrgTPO (IrgacureTPO; manufactured by BASF, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide)
(Component D: Adhesive-imparting resin)
YS-K125 (YS Polystar K125; manufactured by Yasuhara Chemical Co., Ltd .; terpene phenol resin)

(Surface hardening test)
The photocurable composition was applied to an adherend (PET film) using a glass rod so as to have a thickness of 200 μm. Next, the photocurable composition on the adherend was irradiated with ultraviolet rays (UV) [irradiation conditions: UV-LED lamp (wavelength 365 nm, illuminance: 1000 mW / cm ² ), integrated light intensity: 3000 mJ / cm ² ]. .. Immediately after UV irradiation, the surface curability was tested by touch in a dark room and in an environment of 23 ° C. and 50% RH. The case where the liquid substance did not adhere to the finger was evaluated as "○", and the case where the liquid substance adhered to the surface of the finger was evaluated as "x".

(Hardness test [Asuka C hardness])
The hardness test was carried out in accordance with SRIS0101 of the Japan Rubber Association standard (SRIS). First, the photocurable composition was applied to an adherend (PET film) in the form of a sheet having a length of 5 cm, a width of 20 cm, and a thickness of 200 μm using a glass rod. Next, the photocurable composition on the adherend was irradiated with light and cured [irradiation conditions: metal halide lamp (illuminance: 600 mW / cm ² , integrated light intensity: 6000 mJ / cm ² ]. The cured product of the photocurable composition was cut into 20 pieces of 5 cm in length × 1 cm in width with a cutter, and the 20 pieces of the cut pieces were stacked to make the total thickness of the cured product of the photocurable composition 4 mm. Subsequently, the hardness of the cured product was measured using a hardness tester (Asuka hardness tester type C). The unit of hardness is ASKER C, and if the measured value is x, the hardness is represented by ASKER Cx. ..

(Peeling adhesive strength test)
The photocurable pressure-sensitive adhesive composition according to Example 1 was applied to a first adherend (PET film) using a glass rod so as to have a thickness of 200 μm. Next, the photocurable pressure-sensitive adhesive composition on the first adherend was irradiated with ultraviolet rays (UV) [irradiation conditions: UV-LED lamp (wavelength 365 nm, illuminance: 1000 mW / cm ² ), integrated light intensity: 3000 mJ. / Cm ² ]. Immediately after UV irradiation, a second adherend (austenitic stainless steel) having an area of 25 mm × 80 mm was attached to the first adherend so as to sandwich the UV-irradiated photocurable pressure-sensitive adhesive composition. Pressure was applied using a 2 kg roller. As a result, a test piece was prepared. Immediately after applying pressure to the test piece, the peel strength was measured at a test speed of 200 mm / min in accordance with JIS K6854-2 (Adhesive-Peeling Adhesive Strength Test Method Part 2: 180 Degree Peeling Method). .. The test results are shown in Table 1. Examples 2 to 9 and Comparative Examples 1 and 2 were also tested in the same manner.

As can be seen from Table 1, in Examples 1 to 9, it was shown that the peel-off adhesive strength was good at least 14 (N / 25 mm) or more. On the other hand, in Comparative Example 1, the peeling adhesive strength could not be measured because it was not adhesive and could not be bonded, and in Comparative Example 2, the peeling adhesive strength did not reach 10 (N / 25 mm). Was shown.

(LED chip bonding test)
1 (a) and 1 (b) show the outline of the printed circuit board and the LED chip used in the LED chip bonding test. Further, FIG. 2 shows an outline of the process of attaching the LED chip to the printed circuit board. Note that FIG. 2 is described using the AA cross section in FIG. Further, FIGS. 1 and 2 are schematic views and do not correspond to actual shapes and dimensions.

In this test, the LED chip bonding test was carried out using the photocurable pressure-sensitive adhesive composition according to Example 1. Specifically, first, a wiring pattern 12 and a wiring pattern 14 made of copper as shown in FIGS. 1 (a) and 2 (a), a mounting portion 16 and a mounting portion 18 made of copper, and a terminal electrode made of copper. A printed circuit board 10 on which 20 and the terminal electrode 22 were printed was prepared. Further, an LED chip 30 (manufactured by Linkman Co., Ltd., product model number: HT17-21SRWC, emission wavelength at a forward current of 20 mA: 624 nm to 630 nm) as shown in FIG. 1 (b) was prepared. The LED chip 30 is electrically connected to the chip substrate 32, an LED element (not shown) mounted on the chip substrate 32, and an anode electrode of the LED element, and is provided at one end of the chip substrate 32. It includes a connection electrode 34, a connection electrode 36 that is electrically connected to the cathode electrode of the LED element and is provided at the other end of the chip substrate 32, and a sealing portion 38 that seals the LED element.

Next, the metal mask 40 having the opening 40a was installed on the printed circuit board 10. Specifically, as shown in FIG. 2B, the metal mask 40 was installed on the printed circuit board 10 so that the opening 40a corresponds to the mounting portion 16 and the mounting portion 18 of the printed circuit board 10. Then, by screen printing, a moisture-curable conductive adhesive layer 42 and a moisture-curable conductive adhesive layer 44 made of a moisture-curable conductive adhesive (modified silicone type, product name: SX-ECA48, manufactured by Cemedine Co., Ltd.) are formed. (See FIG. 2 (c)). The thickness of the moisture-curable conductive adhesive layer 42 and the moisture-curable conductive adhesive layer 44 was set to 115 μm.

Subsequently, as shown in FIG. 2D, the photocurable pressure-sensitive adhesive composition 46 according to Example 1 was dispensed between the mounting portions 16 and the mounting portions 18 of the printed circuit board 10 with a thickness of 100 μm. Then, the photocurable pressure-sensitive adhesive composition 46 on the printed circuit board 10 was irradiated with ultraviolet rays (UV) (irradiation conditions: UV-LED lamp (wavelength 365 nm, illuminance 1000 mW / cm ² ), irradiation time: 3 seconds). Immediately after the UV irradiation, the LED chip 30 was mounted on the printed circuit board 10 as shown in FIG. 2 (e). In this case, the connection electrode 34 comes into contact with the moisture-curable conductive adhesive layer 42 on the mounting portion 16, and the connection electrode 36 contacts the moisture-curable conductive adhesive layer 44 on the mounting portion 18, and the LED chip. It was mounted so that the photocurable pressure-sensitive adhesive composition 46 was in contact with the bottom of the 30 except for the connection electrode 34 and the connection electrode 36.

Immediately after mounting, a force was applied to the LED chip 30 (the direction in which the force was applied is the shearing direction). As a result, it was confirmed that the LED chip 30 was sufficiently fixed to the printed circuit board 10.

After that, the moisture-curable conductive adhesive layer 42 and the moisture-curable conductive adhesive layer 44 were cured by leaving them in an environment of 23 ° C. and 50% RH for 24 hours, and then the terminal electrode 20 and the terminal electrode 22 were attached to the LED chip 30. When a current of 20 mA was applied through the LED chip 30, it was confirmed that the LED chip 30 emitted red light.

Although the embodiments and examples of the present invention have been described above, the embodiments and examples described above do not limit the invention according to the claims. In addition, not all combinations of features described in the embodiments and examples are indispensable for the means for solving the problems of the invention, and various kinds as long as they do not deviate from the technical idea of the present invention. It should be noted that it can be transformed.

10 Printed circuit board 12, 14 Wiring pattern 16, 18 Mounting part 20, 22 Terminal electrode 30 LED chip 32 Chip substrate 34, 36 Connection electrode 38 Sealing part 40 Metal mask 40a Opening 42, 44 Moisture-curable conductive adhesive layer 46 Photocurable adhesive composition

Claims (4)

It is a method of adhering multiple adherends.
(A) Monoacrylate represented by the following general formula (1) or general formula (2),
(B) Radical polymerizable oligomer and
(C) A coating step of applying a photocurable pressure-sensitive adhesive composition containing a photoinitiator and exhibiting stickiness by light irradiation to at least one adherend.
A light irradiation step of irradiating the photocurable pressure-sensitive adhesive composition applied to one of the adherends with light emitted from an LED in the presence of oxygen.
The other adherend (excluding the protective sheet on the adhesive surface as the other adherend) is adhered to the photocurable pressure-sensitive adhesive composition applied to the one adherend and irradiated with the light. Adhesive method including the process of

(In the general formula (1) and the general formula (2), R ¹ represents −H or −CH ₃ , and R ² is a substituted or unsubstituted alkyl group, or − ( _Cm H _2m O) _n R ³ Indicates a group, in-( _Cm H _2m O) _n R ³ groups, m is an integer of 2 to 4, n is an integer of 1 to 30, R ³ is -H, or an unsubstituted or substituted alkyl group. .) The bonding method according to claim 1, wherein the photocurable pressure-sensitive adhesive composition further contains (D) a pressure-sensitive adhesive resin. A method for producing an adhesive body produced by using the adhesive method according to claim 1 or 2. A photocurable pressure-sensitive adhesive composition that exhibits adhesiveness when irradiated with light emitted from an LED in the presence of oxygen.
(A) Monoacrylate represented by the following general formula (1) or general formula (2),
(B) Radical polymerizable oligomer and
(C) A photocurable pressure-sensitive adhesive composition containing a photoinitiator.

(In the general formula (1) and the general formula (2), R ¹ represents −H or −CH ₃ , R ² is a substituted or unsubstituted alkyl group, or − ( _Cm H _2m O) _n R ³ Indicates a group, in-( _Cm H _2m O) _n R ³ groups, m is an integer of 2 to 4, n is an integer of 1 to 30, R ³ is -H, or an unsubstituted or substituted alkyl group. .)

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