JPWO2019073980A1 - Photocurable pressure-sensitive adhesive composition and bonding method - Google Patents

Abstract

A photocurable pressure-sensitive adhesive composition containing a urethane oligomer having a crosslinkable silicon group, in which photopolymerization proceeds rapidly even in the presence of oxygen such as in the air, and long-term light irradiation and oxygen blocking equipment are not required. Provided are a photocurable pressure-sensitive adhesive composition in which the peeling strength of the pressure-sensitive adhesive at a high temperature is significantly improved, and a bonding method. The photocurable pressure-sensitive adhesive composition contains (A) a radically polymerizable urethane oligomer having a crosslinkable silicon group, (B) a monofunctional radically polymerizable compound, and (C) a photoinitiator.

Description

The present invention relates to a photocurable pressure-sensitive adhesive composition and an bonding method. In particular, the present invention relates to a photocurable pressure-sensitive adhesive composition having a high peeling strength of the pressure-sensitive adhesive at a high temperature, and a bonding method.

In Patent Document 1, 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) and the saturated alcohol. An active energy ray-curable pressure-sensitive adhesive composition containing the hydroxyl group (a4), a polyisocyanate derivative [A] forming a urethane bond, and an ethylenically unsaturated monomer [B] is disclosed. Has been done. The active energy ray-curable pressure-sensitive adhesive composition described in Patent Document 1 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 1, 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. Further, in Patent Document 1, although the holding power of the pressure-sensitive adhesive is measured at 40 ° C., the peel strength at a high temperature exceeding 40 ° C. is not examined, and the improvement of the peel strength of the pressure-sensitive adhesive at a high temperature is solved. It has not been.

Japanese Unexamined Patent Publication No. 2003-155455

The problem to be solved by the present invention is a photocurable pressure-sensitive adhesive composition containing a urethane oligomer having a crosslinkable silicon group, in which photopolymerization proceeds rapidly even in the presence of oxygen such as in the air for a long time. It is an object of the present invention to provide a photocurable pressure-sensitive adhesive composition, which does not require light irradiation or oxygen blocking equipment and significantly improves the peeling strength of the pressure-sensitive adhesive at high temperatures, and a bonding method.

In order to achieve the above object, the present invention is photocurable containing (A) a radically polymerizable urethane oligomer having a crosslinkable silicon group, (B) a monofunctional radically polymerizable compound, and (C) a photoinitiator. A sex tackle composition is provided.

Further, in the above photocurable pressure-sensitive adhesive composition, the (B) monofunctional radically polymerizable compound comprises a monofunctional (meth) acrylate, a vinyl-based monofunctional compound having an amide group, and a monofunctional N-vinyl compound. It is preferably at least one compound selected from the group.

Further, in order to achieve the above object, the present invention provides a product having a cured product of the above photocurable pressure-sensitive adhesive composition.

Further, the present invention is a method for adhering a plurality of adherends in order to achieve the above object, wherein (A) a radically polymerizable urethane oligomer having a crosslinkable silicon group and (B) a monofunctional radical polymerizable. A coating step of applying a photocurable pressure-sensitive adhesive composition containing a compound and (C) a photoinitiator to at least one adherend, and a photocurable pressure-sensitive adhesive composition applied to one of the adherends. A light irradiation step of irradiating light emitted from an LED in the presence of oxygen, and a photocurable pressure-sensitive adhesive composition applied to one adherend and irradiated with light to the other adherend (however, the other). An adhesion method comprising a step of adhering (excluding a protective sheet for an adhesive surface) as an adherend is provided.

Further, in order to achieve the above object, the present invention provides a method for manufacturing an adhesive body manufactured by using the above bonding method.

According to the photocurable pressure-sensitive adhesive composition and the bonding method according to the present invention, the photocurable pressure-sensitive adhesive composition contains a urethane oligomer having a crosslinkable silicon group and is photopolymerized even in the presence of oxygen such as in the air. It is possible to provide a photocurable pressure-sensitive adhesive composition and a bonding method, which proceed rapidly, do not require long-term light irradiation or oxygen blocking equipment, and significantly improve the peeling strength of the pressure-sensitive adhesive at high temperatures.

The photocurable pressure-sensitive adhesive composition of the present invention is a composition that quickly exhibits adhesiveness by irradiation with light such as an active energy ray emitted from a light emitting diode (LED), and then moisture-cures. It is a composition in which the peeling strength of the pressure-sensitive adhesive after moisture curing at high temperature is significantly improved. That is, the photocurable pressure-sensitive adhesive composition contains (A) a radically polymerizable urethane oligomer having a crosslinkable silicon group, (B) a monofunctional radically polymerizable compound, and (C) a photoinitiator. Further, the photocurable pressure-sensitive adhesive composition may be referred to as (A) a radical-polymerizable oligomer excluding a radical-polymerizable urethane oligomer having a crosslinkable silicon group (hereinafter, A'component, or simply a "radical-polymerizable oligomer"". ) And / or a tackifier resin may be further contained. In the present invention, the "high temperature" refers to a temperature exceeding room temperature, which is about 80 ° C.

(Component A: Radical-polymerizable urethane oligomer having a crosslinkable silicon group)
The radically polymerizable urethane oligomer having a crosslinkable silicon group of component A has a crosslinkable silicon group, and the radically polymerizable group is linked to the main chain skeleton of the oligomer via a urethane bond (-OC (= O) N-). It is an oligomer. The main chain skeleton of the oligomer is an oligomer having a number average molecular weight of 1,000 or more, such as polyether-based, polyester-based, non-aromatic polycarbonate-based, acrylic-based, and diene polymerization system (hereinafter, "polymerization having a crosslinkable silicon group"). Sometimes referred to as "sex oligomer").

The number average molecular weight of the polymerizable oligomer having a crosslinkable silicon group is preferably 2,000 or more, more preferably 3,000 or more, and more preferably 5,000 or more in terms of polystyrene in GPC from the viewpoint that the pressure-sensitive adhesive exhibits good peel strength. The above is more preferable. From the viewpoint of ensuring an appropriate viscosity of the photocurable pressure-sensitive adhesive composition and ensuring good workability, the number average molecular weight is preferably about 100,000 or less, more preferably 50,000 or less, and further 30,000 or less. preferable. 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 even more preferably to show a liquid at 0 ° C. The glass transition point (Tg) is preferably 10 ° C. or lower, more preferably 0 ° C. or lower, and even more preferably −10 ° C. or lower, from the viewpoint that the pressure-sensitive adhesive is flexible at low temperatures and maintains and improves the adhesive strength.

The radical polymerizable group in the polymerizable oligomer having a crosslinkable silicon group is contained in the urethane 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 a (meth) acryloyloxy group (CH ₂ = CR'C (= O) O−; R'represents a hydrogen or methyl group)) and a (meth) acryloyl (substituted) amino group. (CH ₂ = CR'C (= O) NR''-;R'represents a hydrogen or methyl group and R'' represents a hydrogen or alkyl group)) from the viewpoint of storage stability (meth). ) A compound having an acryloyloxy group is preferable. From the viewpoint of reactivity, a compound having a (meth) acryloyl (substituted) amino group is preferable. In terms of reactivity, the (meth) acryloyloxy group is a 3- (meth) acryloyloxy-2-hydroxypropyl group (CH ₂ = CR ^α C (= O) O-CH ₂ CH (OH) CH ₂ ). A compound having −,) is preferable. In addition, R ^α represents a hydrogen or a methyl group.

The crosslinkable silicon group in the polymerizable oligomer having a crosslinkable silicon group may be contained in the urethane oligomer and / or at the terminal, and may be linked to the urethane oligomer via a (thio) urethane bond or a urea bond.

As a result of examining various compositions by the present inventor, the peel strength of the photocurable pressure-sensitive adhesive composition according to the present invention is significantly improved as compared with the conventional pressure-sensitive adhesive, and the adherend and the present invention It was found that the pressure-sensitive adhesive was peeled off from the interface with the pressure-sensitive adhesive, and the pressure-sensitive adhesive was not coagulated and destroyed. The reason for this is not clear, but it is presumed that the cause of the significant improvement in peel strength at least at high temperatures is not due to the improvement in cohesive force due to the increase in cross-linking points. Although the detailed mechanism is unknown, in the photocurable pressure-sensitive adhesive composition according to the present invention, the crosslinkable silicon group is moisture-cured by a dark reaction after curing by a photoreaction, so that the peeling strength of the pressure-sensitive adhesive at high temperature is high. Is a composition that greatly improves.

[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 (1).

In the formula, R ¹ 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 ¹ 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 (1). When a is 3, the curing rate is higher than when a is 2.

Specific examples of R ¹ include alkyl groups such as methyl group and ethyl group, substituted alkyl groups such as methoxymethyl group, cycloalkyl groups such as cyclohexyl group and the like. 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 (1), 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 ² ) ₃ ); a dialkoxysilyl group such as a methyldimethoxysilyl group and a methyldiethoxysilyl group. Alkoxysilyl groups (-SiR ¹ (OR ² ) ₂ ) can be mentioned. Here, R ¹ is the same as described above, and R ² 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 the position where the crosslinkable silicon group is contained, the terminal of the urethane oligomer is preferable from the viewpoint of obtaining a pressure-sensitive adhesive having sufficient peel strength. The ratio of the crosslinkable silicon groups is preferably 10% or more with respect to the total number of radically polymerizable groups and crosslinkable silicon groups in the urethane oligomer from the viewpoint of improving the peeling strength of the pressure-sensitive adhesive after curing at high temperature. Percentage or more is more preferable, and 40% or more is further preferable. Further, from the viewpoint of curability immediately after photocuring, 90% or less is preferable, 80% or less is more preferable, and 70% or less is further preferable.

(Synthesis of polymerizable oligomer having crosslinkable silicon group)
The polymerizable oligomer having a crosslinkable silicon group is a reaction product of a hydroxyl group-containing oligomer and an organic polyisocyanate, a hydroxyl group-containing radical polymerizable compound, a crosslinkable silicon group such as 3-mercaptopropyltrimethoxysilane, and an isocyanate-reactive group. It can be synthesized by reacting with a compound having. Examples of the isocyanate-reactive group include a mercapto group, an amino group, and a substituted amino group.

Further, by reacting a hydroxyl group-containing radical polymerizable compound with a reaction product of an oligomer containing a hydroxyl group and a crosslinkable silicon group (hereinafter, referred to as “hydroxyl group and a crosslinkable silicon group-containing oligomer”) and an organic polyisocyanate. It can also be synthesized. The hydroxyl group and the crosslinkable silicon group-containing oligomer can be synthesized by copolymerizing a monomer having a crosslinkable silicon group at the time of synthesizing the hydroxyl group-containing oligomer. Further, a hydroxyl group-containing oligomer may be synthesized using an initiator having a crosslinkable silicon group, a chain transfer agent having a crosslinkable silicon group, or the like, and the hydroxyl group-containing oligomer may be crosslinked with 3-isocyanatepropyltrimethoxysilane or the like. It can also be synthesized by reacting a compound containing a silicon group and an isocyanate group.

Further, the polymerizable oligomer having a crosslinkable silicon group is synthesized by reacting a hydroxyl group and a crosslinkable silicon group-containing oligomer or a hydroxyl-terminated urethane oligomer having a crosslinkable silicon group with a (meth) acrylate containing an isocyanate group. You can also do it. The hydroxyl-terminated urethane oligomer having a crosslinkable silicon group 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 50 ° 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 more 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, amorphous (1,6-hexanediol / 1,5-pentanediol copolymerization, 1,6-hexanediol / 1,4-butanediol copolymerization, etc.) in which monomers having different unit chain lengths are copolymerized. 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) cryloyloxypropyltrimethoxysilane in combination, a crosslinkable silicon group can be introduced into the main chain of the acrylic hydroxyl group-containing oligomer. Can be done. 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.

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 mono (meth) acrylate. Among them, the polymerizable oligomer having a crosslinkable silicon group capped with glycerin mono (meth) acrylate is a (meth) acrylic acid 2-hydroxypropyl group (CH ₂ = CR'C (= O) OCH linked by a urethane bond. ₂ CH (OH) CH _2- , R'indicates a hydrogen atom or a methyl group), so it is placed in a portion sandwiched between two polar groups ((meth) acryloyloxy group and urethane bond). -CH ₂ groups are contained in a secondary hydroxyl group, and polymerization inhibition by oxygen can be suppressed. Therefore, it is particularly preferable because oxygen inhibition is unlikely to occur and the surface curability is good.

(Mechanism of suppressing polymerization inhibition by oxygen)
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, a compound having a plurality of electron-withdrawing groups and in which active radicals are likely to be generated in a portion sandwiched between the plurality of electron-withdrawing groups, for example, the above-mentioned compound having a function as a chain transfer agent in a system ( Meta) When a polymerizable oligomer having a 2-hydroxypropyl acrylate group is present, a peroxy radical having a hydrogen abstraction ability abstracts hydrogen from the polymerizable oligomer to generate a newly generated α-carbon radical of a secondary hydroxyl group. Is thought to 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.

Examples of the hydroxyl group-containing (meth) acrylamide compound include N-substituted (meth) acrylamide (for example, N-mono-substituted (meth) acrylamide and N, N-di-substituted (meth) acrylamide), and examples thereof include JP-A-2016-. Examples thereof include (meth) acrylamide compounds having a hydroxyl group described in Japanese Patent Application Laid-Open No. 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) acrylamides 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-isocyanate ethyl (meth) acrylate.

(Component B: monofunctional radically polymerizable compound)
Examples of the monofunctional radically polymerizable compound of the component B include a monofunctional (meth) acrylate having a number average molecular weight of less than 1,000, a vinyl-based monofunctional compound having an amide group, and a monofunctional N-vinyl compound. Be done.

The blending ratio of the B component is 100 parts by mass in total of the A component or the A component and the A'component (radical polymerizable oligomer) from the viewpoint of exerting the effect of improving the peeling strength of the adhesive at high temperature by the A component. On the other hand, 2,000 parts by mass or less is preferable, 1,000 parts by mass or less is more preferable, and 300 parts by mass or less is most preferable. From the viewpoint of improving the coating workability of the photocurable pressure-sensitive adhesive composition, 2 parts by mass or more is preferable, 5 parts by mass or more is more preferable, and 10 parts by mass or more is most preferable.

(Monofunctional (meth) acrylate)
When the monofunctional (meth) acrylate as the component B is added to the photocurable pressure-sensitive adhesive composition, the viscosity is lowered without lowering the stickiness, and therefore, from the viewpoint of improving the coatability (workability) of the composition. preferable. As the monofunctional (meth) acrylate, a monofunctional (meth) acrylate having a number average molecular weight of less than 1,000 can be used. The monofunctional (meth) acrylate is preferably liquid at 50 ° C. from the viewpoint of ease of compounding and the like.

Examples of the monofunctional (meth) acrylate include a monofunctional (meth) acrylate represented by the following general formula (2).

CH ₂ = CR ³ COO ( _Cm H _2m O) _n R ⁴ ... (2)

However, in the general formula (2), R ³ is a hydrogen atom or a methyl group, m is an integer of 2 to 4, n is an integer of 1 to 20, and R ⁴ is a hydrogen atom or an unsubstituted or substituted alkyl group. Indicates an unsubstituted or substituted phenyl group.

Specifically, as a monofunctional (meth) acrylate, a (meth) acrylate in which R ⁴ has a hydroxyl group such as a compound of a hydrogen atom or an aliphatic epoxy (meth) acrylate in the general formula (2); R in the general formula (2). ⁴ is an unsubstituted or having an alkoxy group of compounds of the substituted alkyl group (meth) acrylate; compounds of the general formula (2) R ⁴ is an unsubstituted or substituted phenyl group, aromatic such as aryl (meth) acrylate (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 (2) 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.

As the (meth) acrylate having a hydroxyl group, a monomer having one 3- (meth) acryloyloxy-2-hydroxypropyl group linked by a polar linking group A represented by the following general formula (3) (hereinafter, "" It is described as "3Ac2HPM"), which is preferable from the viewpoint that oxygen inhibition is unlikely to occur.

In the general formula (3), R ³ represents a hydrogen atom or a methyl group, A represents a polar linking group, and R ⁵ represents an organic group.

Polar linking groups include (thio) ether linking group, ester (-O-CO-) linking group, urethane (-O-CO-NH-) linking group, amine (-NR ⁶ _2- ) linking group (R ⁶ ). a substituted or unsubstituted alkyl group are well linked to the ring structure may have.) cited be the same or different .2 one R ⁶ groups of a substituted or unsubstituted aryl group .. As the linking group, an ether (-O-) linking group, an ester linking group and a urethane linking group are preferable, and an ether linking group and a urethane linking group are more preferable, from the viewpoint of suppressing polymerization inhibition by oxygen. The ether linking group is most preferable because of its availability.

Examples of the organic group of R ⁵ include a substituted or unsubstituted alkylene group, a substituted or unsubstituted phenyl group, and a group of the following general formula (4).

-(C _m H _2m O) _n R ⁷ ... (4)

In the general formula (4), m is an integer of 2 to 4, n is an integer of 1 to 20, and R ⁷ is a hydrogen atom or an unsubstituted or substituted alkyl group, or an unsubstituted or substituted phenyl group. As the organic group for R ⁵ is preferably an alkyl group having 8 to 18 carbon atoms. Further, crosslinkable silicon group-containing groups such as 3-triethoxysilylpropyl group as the organic group for R ⁵ may be a dual cure (post-curing), adhesion, and from the viewpoint of improving the adhesiveness at a high temperature.

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.

A (meth) acrylate having a polar group such as a hydroxyl group, a carboxyl group, or a phenoxy group is preferable because it enhances the cohesive force of the pressure-sensitive adhesive and improves the pressure-sensitive adhesive strength.

The (meth) acrylate having an alicyclic group is preferable because it has good curability, the adhesive strength does not easily decrease, and the performance balance is good.

The blending ratio of the B component is 2,000 parts by mass or less with respect to 100 parts by mass of the A component (or the total of the A component and the A'component) from the viewpoint of exerting the effect of improving the adhesive strength of the A component. It is preferably 1,000 parts by mass or less, more preferably 300 parts by mass or less. From the viewpoint of improving the coating workability of the composition, 2 parts by mass or more is preferable, 5 parts by mass or more is more preferable, and 10 parts by mass or more is most preferable.

When a vinyl-based monofunctional compound having an amide group or a monofunctional 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, a vinyl-based monofunctional compound having an amide group and a monofunctional N-vinyl compound are preferable from the viewpoint of reactivity and the fact that oxygen inhibition is unlikely to occur.

(Vinyl-based monofunctional compound having an amide group)
Examples of the vinyl-based monofunctional compound having an amide group include a compound having one vinyl group having an amide group, and examples thereof include N-vinyl such as N-vinyl-2-pyrrolidone and N-vinyl-2-caprolactam. Cyclic amides; acrylamides such as N, N-diethyl (meth) acrylamide, N- (2-hydroxyethyl) acrylamide, and (meth) acrylic loylmorpholin. Acryloyl morpholine is preferable because it has a good balance of curability, physical properties, and safety.

(Monofunctional N-vinyl compound)
Examples of the monofunctional N-vinyl compound include compounds having one monofunctional N-vinyl group, and examples thereof include N-vinylpyrrolidone, N-vinylcaprolactam, and N-vinylacetamide. N-vinylpyrrolidone is preferable because it has a good balance between curability and physical properties.

(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 benzoylbenzoate, 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 crosslinkable silicon radicals when irradiated with light, it is preferable to use a photobase generator because the component A of the present invention contains crosslinkable silicon groups. Further, when the photocurable pressure-sensitive adhesive composition contains (B) a monofunctional radically polymerizable compound and (B) the monofunctional radically polymerizable compound contains a crosslinkable silicon group, a high effect is exhibited.

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, curing does not proceed to a deep part and curing failure may occur. Therefore, "component A" or "component A and component A'" 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 parts by weight with respect to 100 parts by weight of "A component" or "A component and A'component". The following is preferable, 20 parts by weight or less is more preferable, and 10 parts by weight or less is further preferable.

(Silicon compound having Si—F bond)
Further, the photocurable pressure-sensitive adhesive composition preferably contains a photobase generator as a photoinitiator. As a curing accelerator, a silicon compound having a Si—F bond can be further added. Since the component A and / or the component B contained in the photocurable pressure-sensitive adhesive composition has a crosslinkable silicon group, the photo-curable pressure-sensitive adhesive composition is photo-cured, and then the photo-curable pressure-sensitive adhesive is subjected to moisture in the air. The composition can be post-cured.

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.

(A'component: radically polymerizable oligomer)
The photocurable pressure-sensitive adhesive composition according to the present invention may further contain (A) a radically polymerizable oligomer (A'component) other than the radically polymerizable urethane oligomer having a crosslinkable silicon group. The radically polymerizable oligomer as the A'component is a radically polymerizable oligomer excluding the polymerizable oligomer having a crosslinkable silicon group of the A component, and has a number average molecular weight in which the radically polymerizable group is bonded to the oligomer terminal or side chain. There are more than 1,000 oligomers.

The position of the radically polymerizable group in the radically polymerizable oligomer is preferably the terminal of the radically polymerizable oligomer from the viewpoint of obtaining a pressure-sensitive adhesive having sufficient peeling strength. Examples of the radically polymerizable group include a (meth) acryloyloxy group and a (meth) acryloyl (substituted) amino group, 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 terms of reactivity, the (meth) acryloyloxy group is a 3- (meth) acryloyloxy-2-hydroxypropyl group (CH ₂ = CHR ¹ C (= O) O-CH ₂ CH (OH) CH ₂ ). -, R ¹ represents 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), diene (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 skeletons of polyether-based, polyester-based, non-aromatic polycarbonate-based, acrylic-based, and diene polymerization-based oligomers.

The number average molecular weight of the radically polymerizable oligomer is preferably 2,000 or more, more preferably 3,000 or more, still more preferably 5,000 or more in terms of polystyrene in GPC from the viewpoint that the pressure-sensitive adhesive exhibits good peel strength. From the viewpoint of ensuring an appropriate viscosity of the photocurable pressure-sensitive adhesive and ensuring good workability, the number average molecular weight is preferably about 100,000 or less, more preferably 50,000 or less, and even 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 even more preferably to show a liquid at 0 ° C. From the viewpoint that the pressure-sensitive adhesive is flexible at low temperatures and maintains and improves the adhesive strength, a radical-polymerizable oligomer having a glass transition point (Tg) of 10 ° C. or lower is preferable, and a radical-polymerizable oligomer having a glass transition point (Tg) of 0 ° C. or lower is more preferable. Radical polymerizable oligomers at ° C. or lower are more preferable.

The blending ratio of the A'component is preferably 200 parts by mass or less, more preferably 150 parts by mass or less with respect to 100 parts by mass of the A component, from the viewpoint of exerting the effect of improving the peeling strength of the pressure-sensitive adhesive at high temperature by the A component. It is preferably 80 parts by mass or less, and most preferably 80 parts by mass or less. From the viewpoint of improving the cohesive force of the pressure-sensitive adhesive immediately after photocuring, 2 parts by mass or more is preferable, 5 parts by mass or more is more preferable, and 10 parts by mass or more is most preferable.

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

(Adhesive-imparting resin)
The photocurable pressure-sensitive adhesive composition according to the present invention may further contain a tack-imparting resin. The tackifier resin 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 or aliphatic resin having a relatively small polarity. -Aromatic copolymerization system, various petroleum resins such as alicyclic system, or ordinary tackifier resin such as kumaron resin, low molecular weight polyethylene resin, terpene resin, and resin obtained by hydrogenating these can be used. These may be used alone or in combination of two or more.

Specific examples of these resins include α-methylstyrene copolymer resin [FTR Zero series, manufactured by Mitsui Kagaku Co., Ltd.] and styrene monomer copolymer resin [FTR 8000 series, Mitsui] as aromatic petroleum resins. Chemical Co., Ltd.], Styrene-based monomer / aromatic monomer copolymer resin [FMR series, Mitsui Chemicals Co., Ltd.], α-methylstyrene / styrene copolymer resin [FTR 2000 series, Mitsui Chemicals Co., Ltd.] ) Made] and other aromatic styrene resins. 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 component A or the components A and B. 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 polyfunctional (meth) acrylate, a silane coupling agent, amino group-containing silanes, a photoaminosilane generating compound, a bulking agent, a plasticizer, a water absorber, and a condensation reaction promoting catalyst. , Photosensitizer, photopolymerization accelerator, curing catalyst, physical property adjusting agent for improving tensile properties, reinforcing agent, coloring agent, flame retardant, sagging inhibitor, antioxidant, antiaging agent, ultraviolet absorber, solvent , Perfumes, pigments, dyes, fillers, diluents, polymerization inhibitors, solid polymers and other additives may be added.

(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 parts by mass or less with respect to 100 parts by mass of the A component (or the total of the A component and the A'component) from the viewpoint of exerting the effect of suppressing oxygen inhibition by the A component. Is preferable, 5 parts by mass or less is more preferable, and 2 parts by mass or less is most preferable. From the viewpoint of ensuring sufficient cohesive force under high temperature conditions, 0.01 parts by mass or more is preferable, 0.05 parts by mass or more is more preferable, and 0.1 parts by mass or more is most preferable.

(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)
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 condensation reaction promoting catalyst for other crosslinkable silicon groups other than the C component and the 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. Classes, 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, and coumarin derivatives such as 3-acylcoumarin and 3,3'-carbonylbiscoumarin, preferably thioxanthone and its derivatives and coumarin derivatives, and thioxanthone and its derivatives and benzophenone. 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 dioxide, 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 A component and the A'component, and is in the range of 0.1 to 30 parts by mass. It is more preferable to blend in the range of 0.1 to 15 parts by mass, and it is further preferable to blend 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 applied to the support with active energy rays after drying the composition.

(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 a block copolymer of styrene and a conjugated diene such as butadiene or isoprene, or a hydrogenated product thereof.

Further, 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 of the above 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.

(Adhesion method using a photocurable pressure-sensitive adhesive composition)
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 light irradiation to generate an adhesive on the adherend. This is a method of adhering the other adherend to this. 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 photocurable pressure-sensitive adhesive composition is used as it is for bonding at the site of manufacturing electronic parts and the like. That is, in the present invention, the adhesive is processed into a shape such as a tape to prepare a molded body, and the molded body is not used in a place different from the processing place, but the photocurable pressure-sensitive adhesive composition of the present invention is used. It refers to the application of applying as it is to one adherend and attaching one adherend to the other adherend in that state (or at the site).

(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 the A component, the B component, and the C component are blended, and if necessary, the A'component, the tackifier resin, and / Alternatively, it can be produced by blending other compounding substances and degassing and 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.) in air, and is photocurable at room temperature. It is preferably used as a sex adhesive, but if necessary, curing may be accelerated 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. Then, the photocurable pressure-sensitive adhesive composition according to the present invention is moisture-cured by a dark reaction after photocuring. In addition, various pressure-sensitive adhesive-containing products such as electronic circuits, electronic parts, building materials, and automobiles can be manufactured by using the photocurable pressure-sensitive adhesive composition according to the present invention.

The conditions for irradiating the photocurable pressure-sensitive adhesive composition according to the present invention with light are not particularly limited, but when the active energy rays are irradiated at the time of curing, the active energy rays are cured by ultraviolet rays or visible light. Available. The ultraviolet rays also include g-ray (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.

As the irradiation energy, for example, in the case of ultraviolet rays, 10 to 20,000 mJ / cm ² is preferable, 20 to 10,000 mJ / cm ² is more preferable, and 50 to 5,000 mJ / cm ² is further 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 can be 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 stickiness 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). The photocurable pressure-sensitive adhesive composition used in the bonding method of the present invention is photo-cured by a light irradiation step and then moisture-cured by moisture in the air. 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 its stickiness by light irradiation without blocking from the outside air (even in the presence of oxygen). 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 subject, 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, and even in the presence of oxygen without blocking from the outside air (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.

The photocurable pressure-sensitive adhesive composition according to the present invention is cured by moisture due to a dark reaction after photocuring, so that the peel strength at a high temperature (temperature of about 80 ° C.) can be significantly improved.

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 containing a compound which is usually an α adduct as a main component and a β adduct as a sub component is 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 product obtained by the above synthesis method in which all or a part of the β adduct is left, and is a composition containing the α adduct as a 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.

(Synthesis Example 2: Synthesis of Urethane Acrylate (DC10000-TSi65N))
Reaction product of 2.00 mmol of xylylene diisocyanate (XDI) and 1.90 mmol of N-phenyl-3-aminopropyltrimethoxysilane in 200 g of PPG (polypropylene glycol, Mw / Mn = 1.1, number average molecular weight: 10,000) 21.3 g was reacted, then 1.27 g of glycerin monomethacrylate and 0.05 g of a polymerization inhibitor (hydroquinone) were added and reacted to form a crosslinkable silicon group having a number average molecular weight of 31,000 and being liquid at room temperature. A urethane oligomer (DC10000-TSi65N) having a radically polymerizable PPG skeleton 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 3: Synthesis of Urethane Acrylate (DC10000-TSi65S))
Urethane prepolymer (number average molecular weight) of PPG skeleton at both ends of isocyanate group obtained by reacting PPG (polypropylene glycol, Mw / Mn = 1.1, number average molecular weight: 10,000) with xylylene diisocyanate (XDI). : 9,700) Add 3.55 g of 3-mercaptopropyltrimethoxysilane and 0.05 g of UCAT660M (dimorpholinodiethyl ether) as a catalyst to 125 g and react, and then carry out polymerization with 1.03 g of 2-hydroxyethylacrylamide. 0.05 g of an agent (hydroquinone) was added and reacted to obtain a urethane oligomer (DC10000-TSi65S) having a number average molecular weight of 32,000 and a radically polymerizable PPG skeleton having a crosslinkable silicon group liquid at room temperature. .. As a result of IR spectrum measurement, it was confirmed that the absorption of -NCO derived from the isocyanate group disappeared.

(Synthesis Example 4: 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. The number average molecular weight was 32,000, and 2-hydroxymethacrylate, which was liquid at room temperature. Urethane acrylate (DL-10000-1) having a PPG skeleton at both ends of the propyl 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 5: 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 2-hydroxyethyl acrylamide 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 44,000, and the temperature was normal temperature. A liquid urethane acrylate (DL-10000-2) having a PPG skeleton at both ends of the acryloylaminoethyl group was obtained. As a result of IR spectrum measurement, it was confirmed that the absorption of -NCO derived from the isocyanate group had disappeared.

(Example 1)
Each compounded 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 ratio shown in Table 1, and the mixture is mixed and stirred to perform photocuring 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 each component A, the compounds synthesized in the above Synthesis Examples 2 and 3 were used. Further, as C12MAc of the B component, the compound synthesized in the above synthesis example 1 was used. Further, as the A'components DL-10000-1 and DL-10000-2, the compounds synthesized in Synthesis Example 4 and Synthesis Example 5, respectively, were used.
(Component B: monofunctional radically polymerizable compound)
2-HBA (light acrylate HOB-A; manufactured by Kyoeisha Chemical Co., Ltd., 2-hydroxybutyl acrylate)
ACMO (ACMO; manufactured by kj Chemicals Co., Ltd., acryloyl morpholin)
(C component: photoinitiator)
Irgacure 379 (Irgacure 379; manufactured by BASF, 2- (dimethylamino) -2-[(4-methylphenyl) methyl] -1- [4- (4-morpholinyl) phenyl] -1-butanone)
(Adhesive-imparting resin)
YS-K125 (YS Polystar K125; manufactured by Yasuhara Chemical Co., Ltd .; terpene phenol resin)
(Other condensation reaction promoting catalysts)
Neostan U-830 (Neostan U-830; manufactured by Nitto Kasei Co., Ltd., Dioctyl tin Versate)

(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 amount: 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 (a test piece for a normal temperature peeling adhesive strength test and a test piece for a high temperature peeling adhesive strength were prepared). Then, it was cured for 7 days in an atmosphere of 23 ° C. and 50% humidity.

Subsequently, as a normal temperature peeling adhesive strength test, the test piece prepared in an atmosphere of 23 ° C. was compliant with JIS K6854-2 (Adhesive-Peeling Adhesive Strength Test Method Part 2: 180 ° Peeling Method). , The peel strength was measured at a test speed of 200 mm / min. On the other hand, as a high-temperature peeling adhesive strength test, after leaving the test piece in an atmosphere of 80 ° C. for 30 minutes, the peeling strength of the prepared test piece was measured in the same manner as described above in an atmosphere of 80 ° C. Then, after the peeling adhesive strength test, the fracture state was visually observed. The evaluation criteria are as follows.

(CF): The adhesive was coagulated and broken.
(AF): Peeled off at the adhesive interface between the adherend and the adhesive.

The test results are shown in Table 1. Further, Examples 2 to 9 and Comparative Example 1 were also tested in the same manner.

As can be seen from Table 1, in Examples 1 to 9, good characteristics of at least 1.0 (N / 25 mm) or more were exhibited in the high temperature peeling adhesive strength test. On the other hand, in Comparative Example 1, the peel strength was 0.1 (N / 25 mm), which was extremely weak. In each of the examples, the adhesive was peeled off at the adhesive interface between the adherend and the adhesive in the high temperature peeling adhesive strength test, indicating that the improvement in adhesive strength was not due to the improvement in cohesive force. Was done.

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.

Claims (5)

(A) Radical-polymerizable urethane oligomer having a crosslinkable silicon group and
(B) Monofunctional radically polymerizable compound and
(C) A photocurable pressure-sensitive adhesive composition containing a photoinitiator. The (B) monofunctional radically polymerizable compound is at least one compound selected from the group consisting of a monofunctional (meth) acrylate, a vinyl-based monofunctional compound having an amide group, and a monofunctional N-vinyl compound. The photocurable pressure-sensitive adhesive composition according to claim 1. A product having a cured product of the photocurable pressure-sensitive adhesive composition according to claim 1 or 2. It is a method of adhering multiple adherends.
(A) Radical-polymerizable urethane oligomer having a crosslinkable silicon group and
(B) Monofunctional radically polymerizable compound and
(C) A coating step of applying a photocurable pressure-sensitive adhesive composition containing a photoinitiator 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 A method for producing an adhesive body produced by using the adhesive method according to claim 4.