JP2002356607A - Cationically polymerizable liquid composition and tacky polymerization product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a novel cationic-polymerizable liquid composition which gives a tacky coating film having excellent tack properties such as an adhesion, a holding power, and tack after cationic polymerization, and a tacky polymerization product obtained by cationic polymerization of the same. SOLUTION: A cationic-polymerizable liquid compound comprises (A) a cationic-polymerizable compound containing (A-1) a monofunctional monomer having only one cyclic ether structure to be represented by formula (1) (wherein n is 0, 1 or 2; and R1 -R6 are each a hydrogen atom or a hydrocarbon group which may have a substituent) in the molecule, (A-2) a polyfunctional monomer having two or more cyclic ether structures to be represented by formula (1) in the molecule, and (A-3) a cationic polymerization initiator having latency, and the cationic-polymerizable liquid composition comprises the above compound (A) and a solid resin (B) which is compatible with the above compound at a room temperature and has a softening point of >=40 deg.C, and has a viscosity at 25 deg.C of <=20 Pa.sec. The tacky polymerization product is obtained by cationic polymerization of the composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention can be easily applied to a substrate without containing an organic solvent, and can be used as an adhesive which exhibits good adhesive properties by being polymerized by light or heat after application. The present invention relates to a novel cationically polymerizable liquid composition and an adhesive polymer obtained by cationically polymerizing the cationically polymerizable liquid composition.

[0002]

2. Description of the Related Art As a pressure-sensitive adhesive, a solvent type obtained by dissolving a rubber or acrylic material in an organic solvent or an emulsion type obtained by dispersing in water is conventionally used. Solvent-based pressure-sensitive adhesives are the most widespread at present, but in recent years, scattering of organic solvents has become a problem. Also,
In the case of the emulsion type, water resistance, long drying time, and the like are disadvantageous. Although methods for solving the above problems have been proposed, such as a hot-melt type, they still have low coating properties and adhesive properties, especially low heat resistance.
Recently, a solventless liquid curable pressure-sensitive adhesive mainly comprising a polymerizable monomer has been proposed, for example, there are many proposals regarding a photoradical curable solventless liquid composition using acrylates having radical polymerizability, In polymerization in air, it is difficult to complete radical polymerization due to the effect of inhibiting polymerization of oxygen, and therefore, there are problems such as bad odor and skin irritation caused by residual monomers. Light irradiation in a nitrogen atmosphere has also been proposed as an improvement, but the size of investment in equipment poses a problem.

[0003] Also, a number of cationic photopolymerizable compositions have been proposed as having good photopolymerization properties in air. For example, JP-A-5-78639 discloses a pressure-sensitive adhesive comprising a polymer obtained by copolymerizing an acrylic vinyl monomer having a hydroxyl group, a bifunctional or higher epoxy compound and a cationic polymerization initiator. 8-
Japanese Patent No. 60127 discloses an ultraviolet-curable hot-melt type pressure-sensitive adhesive composition comprising a cyclohexene monoepoxide group-containing thermoplastic acrylic polymer, a polyol and a cationic polymerization type photoinitiator. An acrylic pressure-sensitive adhesive composition comprising an acrylic oligomer obtained by polymerizing a monomer component containing the component and a photocationic catalyst is disclosed. However, since all of these compositions have low polymerizability, a large amount of light irradiation is required for curing at room temperature, and this low polymerizability may pose a problem in actual use.
It is presumed that these compositions have an ester group due to an acrylic group, which delays the ring-opening polymerization of the cyclic ether and reduces the polymerizability. When the molecular weight of the acrylic oligomer is high, the composition may have a high viscosity and may be difficult to apply.

On the other hand, a photocationic polymerization type composition (Eric-Jack Gerard) using a material in which an epoxy group has been introduced by oxidation of a block polymer having an unsaturated bond in the main chain has been proposed as one that can avoid polymerization delay due to an ester group. and Jur
Gen. Schneider, Rad. Tech. Europe 97, 175, 1997) is disclosed. JP-A-2000-26830 discloses a specific epoxy compound, a compound having a functional group reactive with an epoxy group, and rubber elasticity. A UV-curable pressure-sensitive adhesive composition comprising a compound having the compound and a cationic curing catalyst is disclosed. However, all of the compositions have very high viscosities, and the former proposes heating at the time of application, and the latter proposes use of a solvent. JP-A-11-80681 discloses a foam pressure-sensitive adhesive tape using a photocation-reactive oligomer type pressure-sensitive adhesive composition. However, only two types of compositions are disclosed, and one composition is disclosed. The product is the same as that disclosed by Gerard et al. And has the same high viscosity and is difficult to apply,
The other composition is the same as that of JP-A-11-166168, and it can be easily estimated that the curing speed is low. Furthermore, Japanese Patent Application Laid-Open No. 11-158439 discloses that an adhesive material containing a cationically polymerizable compound and a cationic photopolymerization initiator is ejected from a head of an ink jet printer, applied, and then polymerized by light irradiation. Although the bonding method is disclosed, the compositions disclosed in the examples of the publication have low viscosity but low polymerizability, and practicality cannot be found because polymerization hardly proceeds at the irradiation dose described. It is. As mentioned above,
The solvent-free liquid-curable pressure-sensitive adhesives reported so far have simple coatability, can be rapidly polymerized in air, and have the adhesive properties of the pressure-sensitive adhesive film formed by light irradiation. There were no reports on what was good.

[0005]

An object of the present invention is to provide a liquid composition which can be easily applied, has high polymerizability in air, and exhibits adhesiveness and holding power after cationic polymerization. To provide a novel cationically polymerizable liquid composition that provides an adhesive coating film having excellent adhesive properties such as tackiness and tackiness.
Another problem to be solved by the present invention is to provide a tacky polymer excellent in tackiness properties such as adhesion and holding power.

[0006]

Means for Solving the Problems The present inventors have made intensive studies to achieve simple coating properties, high polymerizability in air, and good adhesive properties after polymerization, and as a result, the present invention was completed. It is completed. That is, the above-mentioned problem has a cyclic ether having ring-opening polymerizability as a cationically polymerizable group in a molecule, a monofunctional monomer, a polyfunctional monomer, and a polymerizable compound containing a latent cationic polymerization initiator. (A) and a low viscosity cationic polymerization type liquid composition containing a solid resin (B) compatible with the polymerizable compound (A). Here, the solid resin (B)
Preferably has a softening point of 40 ° C. or higher. Also,
The above “low viscosity” means that the viscosity at 25 ° C. is 20 Pa
・ It means less than sec.

That is, a first aspect of the present invention relates to a monofunctional monomer having only one cyclic ether structure represented by the following formula (1) in a molecule (hereinafter simply referred to as “monofunctional monomer”).
Also called. ) (A-1), a polyfunctional monomer having two or more groups derived from a cyclic ether structure represented by the following formula (1) in the molecule (hereinafter, also simply referred to as “polyfunctional monomer”) (A -2) and a cationically polymerizable compound (A) containing a latent cationic polymerization initiator (A-3), and having a softening point of 40 ° C. or higher which is compatible with the compound (A) at room temperature. The present invention relates to a cationic polymerization type liquid composition which is a liquid resin containing a solid resin (B) and having a viscosity at 25 ° C. of 20 Pa · sec or less.

[0008]

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In the formula, n represents 0, 1 or 2, and R ₁ to
R ₆ represents a hydrogen atom or a hydrocarbon group which may have a substituent.

A second aspect of the present invention is to design the viscoelastic properties of a polymer obtained by cationically polymerizing the cationically polymerizable liquid composition so as to be within a specific range.
The present invention relates to a pressure-sensitive adhesive polymer which gives excellent pressure-sensitive adhesive properties and a polymerizable liquid composition for the pressure-sensitive adhesive polymer.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the cationically polymerizable liquid composition of the present invention and the adhesive polymer obtained by polymerizing the composition will be described in detail.

Cationically polymerizable compound (A) The cationically polymerizable compound (A) is a monofunctional monomer having only one ring-opening polymerizable cyclic ether structure represented by the above formula (1) in the molecule. (A-1), a polyfunctional monomer (A-2) having two or more cyclic ether structures represented by the formula (1) in the molecule, and a latent cationic polymerization initiator (A-3) Contains components as essential components. It is preferable that the cationically polymerizable composition further contains a compound having two or more alicyclic epoxy groups as the polyfunctional monomer (A-2) in order to obtain characteristics excellent in adhesive holding power at high temperatures. `` Alicyclic epoxy group ''
Will be described in detail later. It is also preferable to add a compound having a hydroxyl group at a molecular terminal (described later) as an optional component. The above components of the cationically polymerizable compound (A) will be described in more detail below.

Monofunctional Monomer (Component A-1) The monofunctional monomer is a compound having only one cyclic ether structure in the molecule. Compounds having two or more cyclic ether structures are classified into the following polyfunctional monomers (A-2). This monofunctional monomer is a component used to adjust the viscosity of the polymerizable liquid composition and the glass transition temperature of the polymer obtained by polymerization. The viscosity of the monofunctional monomer used as the component A-1 is 20 mPa · s at 25 ° C.
The viscosity of the monofunctional monomer itself is not particularly limited as long as the viscosity at 25 ° C. of the liquid composition after completion of the blending is 20 Pa · sec or less.

The monofunctional monomers are represented by the following formulas (4) to (6)
And compounds having a three-membered epoxy group, a four-membered oxetanyl group, a five-membered tetrahydrofurfuryl group, and the like. The epoxy group of the formula (4) includes an alicyclic epoxy group having a structure in which a cyclopentene group or a cyclohexene group is epoxidized.

[0015]

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[0016] Equation (4), R ₁ to R ₄ represents, independently, a hydrogen atom or may have a substituent hydrocarbon group, R ₁
And R ₃ may combine to form a cyclic aliphatic group (preferably a cyclohexane ring or a cyclopentane ring) together with the carbon atom to which these groups are attached. Further, the cyclic ether structure represented by the formula (1) is not included in the substituents that substitute the hydrocarbon groups. The same applies to the following expressions (5) and (6). As the hydrocarbon group, one having 1 to carbon atoms
An alkyl group or an aryl group of 36 (also referred to as “C1 to 36” in the present invention) is preferable, an alkyl group or an aryl group of C1 to 24 is more preferable, and a phenyl group and a naphthyl group are preferable as the aryl group. As the substituent of these hydrocarbon groups, any substituent is acceptable as long as it does not inhibit cationic polymerization, and a substituent that does not adversely affect the cationic polymerization is preferable. Examples of the substituent of the alkyl group include a C1-12 alkoxy group, a C2-12 acyloxy group, a C2-12 alkoxycarbonyl group, a phenyl group, a benzyl group, a benzoyl group, a benzoyloxy group, a halogen atom, and a cyano group. , A nitro group, a phenylthio group, a hydroxy group and a triethoxysilyl group. As the substituent of the above aryl group, C
1 to 12 alkyl groups, C1 to 12 alkoxy groups, C
2 to 12 acyloxy groups, alkoxycarbonyl groups,
Examples include a phenyl group, a benzyl group, a benzoyl group, a benzoyloxy group, a halogen atom, a cyano group, a nitro group, a phenylthio group, a hydroxy group and a triethoxysilyl group.

[0017]

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In the formula (5), R _{1 to} R ₆ represent a hydrogen atom or a hydrocarbon group which may have a substituent. As the hydrocarbon group, a C1 to C36 alkyl group or aryl group is preferable, and a C1 to C24 alkyl group or aryl group is more preferable. As the aryl group, a phenyl group and a naphthyl group are preferable. As the substituent of the hydrocarbon group, any substituent is acceptable as long as it does not inhibit the cationic polymerization, and a substituent that does not adversely affect the cationic polymerization is preferable. The group of substituents allowed for this hydrocarbon group is the same as the group of substituents exemplified above when R _{1 to} R ₄ in formula (4) are an alkyl group or an aryl group.

[0019]

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In the formula (6), R _{1 to} R ₈ represent a hydrogen atom or a hydrocarbon group which may have a substituent. As the hydrocarbon group, a C1 to C36 alkyl group or aryl group is preferable, and a C1 to C24 alkyl group or aryl group is more preferable. As the aryl group, a phenyl group and a naphthyl group are preferable. As the substituent of the hydrocarbon group, any substituent is acceptable as long as it does not inhibit the cationic polymerization, and a substituent that does not adversely affect the cationic polymerization is preferable. The group of substituents allowed for this hydrocarbon group is the same as the group of substituents exemplified above when R _{1 to} R ₄ in formula (4) are an alkyl group or an aryl group.

Among them, one of R _{1 to} R ₆ in the above formula (1) is a group represented by the following formula (2) because the viscosity of the finally obtained liquid composition is low. A monofunctional monomer which is a substituent is preferably used in the present invention. That is, the substituent containing the group of the formula (2) can be preferably selected as a hydrocarbon group of the formulas (4) to (6).

[0022]

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In the formula (2), R ₇ and R ₈ are independently a hydrogen atom or an optionally substituted alkyl group, preferably having 1 to 24 carbon atoms, more preferably 1 to 24 carbon atoms. To 10 alkyl groups. R ₉ represents a linear or branched alkyl group having 4 or more carbon atoms, preferably 4 or more and 24 or less carbon atoms, which may have a substituent, and X represents —CH ₂ — or preferably Represents an oxygen atom.

As the substituents permitted for the alkyl groups represented by R ₇ to R ₉ , any substituents are acceptable as long as they do not inhibit the cationic polymerization, and those which do not adversely affect the cationic polymerization are preferable. When R _{1 to} R ₄ in the formula (4) represent an alkyl group, the substituent groups permitted for the alkyl group are the same as the substituent groups exemplified for the alkyl group.

In the present invention, the monofunctional monomer (A-
As 1), a cyclic ether represented by the following formula (3) is particularly preferred.

[0026]

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In the formula (3), R ₇ , R ₈ and R ₁₀ represent a hydrogen atom or an optionally substituted alkyl group having 1 to 10 carbon atoms, and R ₉ represents a C 4 to C 24 alkyl group. Represents a linear or branched alkyl group, and X represents an oxygen atom.
As R ₉ , an alkyl group which may have a substituent having 4 to 24 carbon atoms is preferable, and a C6-16 linear or branched alkyl group is preferable. Substituent groups allowed for this alkyl group are the same as the substituent groups exemplified for this alkyl group when R _{1 to} R ₄ in formula (4) represent an alkyl group.

As specific examples of the compound represented by the formula (3), OXT-212 wherein R ₇ ＲR ₈ ＨH, R ₁₀ = ethyl group, R ₉ = 2-ethylhexyl group, X = oxygen atom,
And OXR-12 (manufactured by Toagosei Co., Ltd.) represented by the following formula (7).

[0029]

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Since the component A-1 has a relatively low molecular weight,
If a large amount of this component remains in the adhesive polymer after polymerization, there is a concern that problems such as bad smell may occur. Use of a monofunctional monomer having an oxetane ring having a high cationic polymerizability can greatly reduce such a problem. Therefore, the oxetane represented by the above formula (3), (5) or (7) is particularly preferable as the component A-1. Monofunctional monomers of the type are preferred.

Polyfunctional Monomer (Component A-2) The component A-2 is a polyfunctional monomer having two or more cyclic ether structures in the molecule, which are the cyclic structures in the above formula (1), and is a cationically polymerizable liquid composition. Viscosity of the product and the viscosity of the polymer obtained by cationic polymerization, in other words,
It is a component used to adjust the complex elastic modulus of the polymer. A linking group that links two or more cyclic ether structures can be appropriately selected. The polyfunctional monomer used as the component A-2 has a viscosity of 2 after the compounding of the cationically polymerizable liquid composition.
It is sufficient that the viscosity be 0 Pa · sec or less, and the viscosity of the polyfunctional monomer itself is not particularly limited.

As the cyclic ether structure of the polyfunctional monomer, a three-membered epoxy group, a four-membered oxetanyl group, and a five-membered tetrahydrofurfuryl group described for the monofunctional monomer are preferable. As a specific chemical structure of the cyclic ether group in the polyfunctional monomer, in the chemical structures represented by the formulas (4) to (6), a hydrogen atom or a hydrocarbon group bonded to a carbon atom forming a ring may be used. A cyclic ether structure in which one hydrogen atom or any residue is removed is exemplified. A polyfunctional monomer having n cyclic ether groups (n is an integer of 2 or more) in the molecule has a chemical structure in which such cyclic ether groups are linked by a single bond or an n-valent organic residue.

Specific examples of the component A-2 include bisphenol A-based epoxy resins, bisphenol F-based epoxy resins, novolak-type epoxy resins and alicyclic epoxy resins generally known as epoxy resins, and commercially available products such as butadiene. EKP-206 and EKP-20 manufactured by Kraton Polymer Co., Ltd., in which an epoxy group is introduced by oxidation of a block polymer having an unsaturated bond in the main chain, which is produced by anionic polymerization of a diene compound and an ethylene compound.
7 (both are trade names). Further, OXT manufactured by Toagosei Co., Ltd., which is an oxetane compound having two or more oxetanyl groups, which are four-membered cyclic ethers, in the molecule.
-121 and OXT-221 (both are trade names), but are not limited thereto.

The alicyclic epoxy compound as the component A-2 The alicyclic epoxy compound as the component A-2 is an effective component for maintaining a high complex elastic modulus at a high temperature. The composition is not particularly limited as long as the viscosity of the composition becomes 20 Pa · sec or less. The alicyclic epoxy compound is a compound having at least one, and preferably 2 to 8 aliphatic cyclic epoxy groups in the molecule.
The alicyclic epoxy group is obtained by epoxidizing a cycloolefin. Specific examples of the alicyclic epoxy compound,
Commercially available Epikote 171 (trade name, Yuka Shell Epoxy Co., Ltd., Araldide CY178 (trade name), Asahi Chiba Co., Ltd., Chissonox 206, Chissonox 205) Co., Ltd., Celloxide 2021, Eporide GT301,
Eporide GT302, Eporide GT401, Eporide GT403 (all of which are trade names, manufactured by Daicel Chemical Industries, Ltd.). As the alicyclic epoxy compound, 3,4-epoxycyclohexylmethyl-3 ′,
4'-Epoxycyclohexanecarboxylate is particularly preferred.

Total amount of component A-1 and component A-2 100
The total amount of the component A-2 is preferably in the range of 5 to 50 parts by mass, more preferably 10 to 40 parts by mass, based on the parts by mass. When the total amount of the cross-linking component A-2 component is less than 5 parts by mass, the complex elastic modulus of the obtained polymer tends to decrease, while when it exceeds 50 parts by mass, the complex elastic modulus becomes too large. Therefore, there is a high possibility of deviating from the range of the complex elastic modulus defined as a preferable range in the present invention. The mixing ratio of the alicyclic epoxy compound as the component A-2 is not particularly limited as long as the complex elastic modulus of the polymer falls within a preferable range, but the total amount of the components A-1 and A-2 is 100 parts by mass. For 1 to
It is preferable to mix 30 parts by mass, more preferably 2 to 20 parts by mass.

Cationic Polymerization Initiator (Component A-3) The cationic polymerization initiator having latency is activated by light or heat (hereinafter, referred to as “photo-latent” and “thermal-latent”, respectively). It is a compound that produces an acid component and acts to induce cationic ring-opening polymerization of the ring-opening polymerizable group in the composition. As the cationic polymerization initiator having photolatent, any cationic photopolymerization initiator can be used as long as the polymerizable liquid composition of the present invention can be activated by being irradiated with light to induce ring opening of the ring-opening polymerizable group. It can be used, and examples of the cationic photopolymerization initiator include onium salts and organometallic complexes. Here, ultraviolet light is preferable as the light that can be activated. The composition of the present invention can be activated by short-wavelength visible light having a wavelength of 390 to 500 nm in combination with a photosensitizer.

The onium salts as the photopolymerization initiator include, for example, diazonium salts, sulfonium salts and iodonium salts. Further, examples of the organometallic complexes include an iron-allene complex, a titanocene complex, and an arylsilanol-aluminum complex. A commercially available product, for example, Optomer SP-150
<< Product name, made by Asahi Denka Kogyo Co., Ltd. >>, Optmer SP-1
70 (trade name, manufactured by Asahi Denka Kogyo Co., Ltd.), UVE-101
4 (trade name, manufactured by General Electronics) and C
D-1012 (trade name, manufactured by Sartomer) can also be used.

As the cationic polymerization initiator having a heat potential, any thermal cationic polymerization initiator can be used as long as it is activated by heating to induce ring opening of the ring-opening polymerizable group, and a quaternary ammonium salt, phosphonium Examples thereof include various onium salts such as salts and sulfonium salts, and organometallic complexes. As the onium salts, for example, Adeka Opton CP-66 and Adeka Opton CP-77 (both are trade names, manufactured by Asahi Denka Kogyo KK), and Sun Aid SI
-60L, Sun-Aid SI-80L and Sun-Aid S
I-100L: All brand names, Sanshin Chemical Industry Co., Ltd.
And commercially available compounds such as CI series (manufactured by Nippon Soda Co., Ltd.). Examples of the organometallic complexes include, for example, an alkoxysilane-aluminum complex.

The latent cationic polymerization initiator (A)
The mixing ratio of -3) is preferably in the range of 0.01 to 5 parts by mass with respect to 100 parts by mass of the total amount of the components A-1 and A-2. When the compounding ratio of the latent cationic polymerization initiator is less than 0.01 parts by mass, the ring-opening reaction of the ring-opening polymerizable group cannot be sufficiently advanced even when activated by the action of light or heat. And the adhesive properties of the polymer after polymerization may be insufficient. Further, even when the amount is more than 5 parts by mass, the effect of promoting the polymerization does not increase any more, and conversely, the initial adhesive strength may decrease.

Solid resin (B) The solid resin (B) has a softening point of 40 ° C. or more,
It is a tackifying resin compatible with the cationic polymerizable compound (A) at room temperature, and is a component for adjusting the viscoelastic properties of the polymer. By adding the solid resin (B) to the cationically polymerizable compound (A), a low frequency (for example, 1H
z), while increasing the complex modulus at high frequencies (eg, about 100 Hz), and generally a tackifying resin (tackifier).
Can be used.

As the solid resin (B), a solid resin having a relatively low molecular weight and a high softening point, which is generally known as a tackifying resin, can be used. For example, a rosin resin, a modified rosin resin, a hydrogenated rosin resin Resins, terpene resins, terpene phenol resins, aromatic modified terpene resins, C5-based or C9-based petroleum resins and hydrogenated products thereof, and tackifying resins such as chroman resins can be used. Compatible with A) at room temperature and has a softening point of 4
It is not particularly limited to these as long as it is a solid resin at 0 ° C. or higher. Among these, the hydrogenated rosin resin and the hydrogenated rosin-based resin are excellent in compatibility with the cationically polymerizable compound (A), can improve transparency of the pressure-sensitive adhesive after curing, and can exhibit strong adhesive strength. Hydrogenated petroleum resins are preferred. The solid resin (B) is composed of the cationic polymerizable compound (A) 1
It is preferably used in an amount of 10 to 300 parts by mass, more preferably 50 to 150 parts by mass, per 100 parts by mass.

Other Optional Additives (Compound Having a Hydroxyl Group at the Molecular End) A monol or polyol compound having a hydroxyl group at the molecular end can also be added to the cationically polymerizable liquid composition of the present invention. Such a terminal hydroxyl group-containing compound is copolymerized into a polymer by a chain transfer reaction. When a compound having a hydroxyl group at one end of a linear molecule is added, the cationic polymerization chain is terminated by a chain transfer reaction, and the hydroxyl group-containing compound is incorporated into the polymer chain. Further, when a compound having a hydroxyl group at both ends of the molecule is added, both ends are incorporated into the polymer chain by chain transfer, and thus may be a crosslinked chain. In this way, by adding the hydroxyl group-containing compound to the cationically polymerizable liquid composition, the viscosity of the composition and the viscoelastic properties of the cured polymer can be adjusted.

Preferred hydroxyl-containing compounds are oligomers or polymers having a low glass transition temperature and a specific range of molecular weight (hereinafter simply referred to as "polymers"), and diols or triols are preferred. The preferred molecular weight range is 300 to 10,000,
It is preferably from 500 to 5,000, particularly preferably from 500 to 3,000. The atoms constituting the main chain of this polymer are preferably only carbon or carbon and oxygen. The number of atoms contained in the main chain connecting the two hydroxyl groups is preferably 20 to 500, more preferably 20 to 200. The above polymer preferably has a glass transition temperature of 0 ° C. or lower.

As a preferred specific example of the terminal hydroxyl group-containing polymer, a compound having a hydroxyl group at one terminal is a branched olefin polymer such as L-manufactured by Kraton Polymer Co., Ltd.
Examples of the compound having a hydroxyl group at both terminals include GI-1000, 2000, and 3000 manufactured by Nippon Soda Co., Ltd., which is a polybutadiene hydrogenated product.

In the composition of the present invention, in addition to the cationically polymerizable compound (A) and the solid resin (B), a known plasticizer, an antiaging agent and An extender or the like may be appropriately blended. Further, for the purpose of improving coatability, a thickener such as acrylic rubber, epichlorohydrin rubber, isoprene rubber and butyl rubber, colloidal silica, a thixotropic agent such as polyvinylpyrrolidone, a filler such as calcium carbonate, titanium oxide and clay, and the like. It may be added. Further, for the purpose of imparting a high-strength shear adhesive force, inorganic hollow bodies such as glass balloons, alumina balloons and ceramic balloons; organic spherical bodies such as nylon beads, acrylic beads and silicon beads; vinylidene chloride balloons and acrylic balloons Organic hollow bodies; single fibers such as glass, polyester, rayon, nylon and cellulose may be added. When blending the above glass fibers, it is possible to add a fibrous chip to the composition, but by impregnating the glass woven fabric with the above photopolymerizable composition and polymerizing, a very high strength is obtained. Can be obtained.

A constituting the cationically polymerizable compound (A)
As for -1 to A-3, the solid resin B, and the other additives described above, one compound may be used, or two or more different compounds may be used in combination.

Next, the measurement conditions and the preferred ranges of various physical properties used in the examples of the present invention will be described. Viscosity The viscosity of the cationically polymerizable liquid composition is 20 at 25 ° C.
In the case of a composition having a viscosity of Pa · sec or less and higher than this, application at room temperature becomes difficult and heating may be required in some cases. Generally, when the latent cationic polymerizable composition is heated, the stability is reduced and the viscosity may be increased, so that the heating is not preferable. In order to obtain good coatability, 25 ° C
Is preferably 10 Pa · sec or less.

Viscoelastic Properties The complex elastic modulus of the polymer in the present invention is a value based on the result measured by a viscoelasticity measurement method using shear shear stress. The cationic polymer obtained by subjecting the composition of the present invention to cationic polymerization has a complex elastic modulus (G ^* ) at each frequency as a viscoelastic property at 25 ° C. which preferably satisfies the following conditions. G ^* > 100,000 (measurement frequency: 0.1 Hz) G ^* <4,000,000 (measurement frequency: 1 Hz) G ^* > 2,000,000 (measurement frequency: 100H)
z) Further, when a predetermined amount of an alicyclic epoxy compound is used as A-2, the complex elastic modulus (G ^* ) at a measuring frequency of 0.1 Hz at 100 ° C. of the polymer satisfies the following condition. It is. G ^* > 100,000 (measurement frequency: 0.1 Hz)

When the complex elastic modulus at 0.1 Hz of the polymer is lower than 100,000, the cohesive force of the polymer is low, and cohesive failure occurs when the polymer is peeled off from the adherend, which is generally called "adhesive residue". Also, the holding power may be reduced, which is not preferable. More preferably, the complex elastic modulus at 0.1 Hz is 200,000 or more. When the complex elastic modulus at 1 Hz is 4,000,000 or more, the polymer becomes hard and does not exhibit initial adhesiveness, which is not preferable. More preferably, the complex elastic modulus at 1 Hz is 3,000,000 or less. The complex elastic modulus at 100 Hz is 2,000,000
If it is lower than 0, the tack value, which is essential as an adhesive, decreases. The complex modulus at 100 Hz is 3,000
More preferably, it is not less than 000. To obtain a high tack value, the loss tangent (Tan
δ) is preferably 0.8 (measurement frequency: 100 Hz) or more, and more preferably 1.0 or more.

Glass Transition Temperature The glass transition temperature (Tg) in the present invention is a value based on the result of a DSC measurement specified in K7121 of Japanese Industrial Standard JIS. The cationic polymer obtained by polymerizing the composition of the present invention has a glass transition temperature of 0.
If the temperature exceeds 100 ° C., it becomes difficult to maintain the above viscoelastic properties. Therefore, the glass transition temperature is preferably 0 ° C. or lower, more preferably −20 ° C. or lower.

The polymerizable liquid composition of the present invention can be used for producing an adhesive polymer. When using the polymerizable liquid composition, for example, paper, plastic laminated paper, cloth, plastic laminated cloth, plastic film, metal foil, foam, etc. as a support, one or both sides of the support, comma roll A gravure coater, a roll coater, a kiss coater, a slot die coater, a suitable coating means such as a squeeze coater, to apply the polymerizable liquid composition of the present invention, polymerized by the action of heat or light, the thickness is reduced. A pressure-sensitive adhesive layer having a thickness of usually 10 to 500 μm is formed on one side to obtain a tape-shaped or sheet-shaped pressure-sensitive adhesive sheet.

The light source that can be used when performing polymerization by light irradiation is not particularly limited,
For example, a low-pressure mercury lamp, a medium-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a chemical lamp, a black light lamp, a microwave-excited mercury lamp, a metal halide lamp, or the like having a light emission energy distribution of 400 nm or less can be used. The light irradiation intensity on the pressure-sensitive adhesive polymer is controlled for each target product and is not particularly limited. However, the light wavelength region (photopolymerization effective for activating the photolatent initiator) is not limited. The light irradiation intensity is usually from 0.1 to 100 mW / cm ² , although the intensity varies depending on the initiator, although light having a wavelength of 300 to 420 nm is usually used.
If the light irradiation intensity on the pressure-sensitive adhesive polymer is less than 0.1 mW / cm ² , the reaction time becomes too long, and the reaction time becomes 100 mW / cm 2.
^If it exceeds ² , there is a possibility that the cohesive strength of the obtained pressure-sensitive adhesive layer is reduced, yellowing occurs, or the support is deteriorated due to heat radiated from the lamp and heat generated during polymerization of the composition.

The light irradiation time on the adhesive polymer is controlled for each target product and is not particularly limited. However, the light irradiation intensity and the light irradiation time in the light wavelength region are not limited. Integrated light quantity expressed as a product is 10 to 5,000 mJ
/ Cm ² is preferably set. When the integrated light amount to the pressure-sensitive adhesive polymer is less than 10 mJ / cm ² , generation of active species from the photolatent initiator is not sufficient, and the pressure-sensitive adhesive property of the obtained pressure-sensitive adhesive layer may be reduced. 5,000 mJ / cm ² , the irradiation time becomes extremely long, which is disadvantageous for improving the productivity. In the case of performing polymerization by heat, heat can be achieved by applying heat to the cationically polymerizable liquid composition of the present invention by a generally known method, and the conditions and the like are not particularly limited.

[0054]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, which should not be construed as limiting the present invention. (Example 1) Oxetane monomer OXR-12 represented by the above formula (7) (manufactured by Toagosei Co., Ltd.), EKP-207 (manufactured by Clayton Polymer Co., Ltd., a multifunctional monomer) (trade name; Shell Chemical Chemical Company's Technical Bu
lletin (1966.10.28-30). ) (A-2)
Component), 2074 (trade name) manufactured by Rhodia Co., Ltd., which is an iodonium salt-based photolatent cation initiator (component A-3),
And Rigalite 1090 (trade name) manufactured by Hercules, which is a hydrogenated petroleum resin having a softening point of about 90 ° C (component B)
Was uniformly mixed at 40 ° C. with the composition (% by mass) shown in Table 1 below to obtain a cationically polymerizable liquid composition.

The obtained composition was applied on a polyethylene terephthalate film (PET film) having a thickness of 50 μm using a doctor blade so as to have a thickness of about 25 μm, and then condensed at 120 W / cm ² . UV light (135 mJ) by passing once under a high pressure mercury lamp (lamp height: 10 cm) at a conveyor speed of 10 m / min.
/ Cm ² ) to form a pressure-sensitive adhesive layer by cationic polymerization to prepare a pressure-sensitive adhesive sheet. Further, the composition was poured onto a polytetrafluoroethylene (manufactured by Teflon (registered trademark) du Pont) plate so as to have a thickness of 1 mm and polymerized under the same irradiation conditions as in the preparation of the pressure-sensitive adhesive sheet for use in measuring viscoelasticity. Then, a polymer for evaluation was prepared by releasing from a Teflon plate.

(Examples 2 to 10 and Comparative Examples 1 and 2) In the same manner as in Example 1, the compositions of Examples 2 to 8 and Comparative Examples 1 and 2 were obtained with the composition shown in Table 1. Note that the oxetane monomer OTX-212 is a monofunctional monomer (A-
One component). L-1203 (manufactured by Clayton Polymer Co., Ltd.) is a completely saturated monool having a molecular weight of 3,600 produced by hydrogenation of linear poly (ethylene / butylene) having a hydroxyl group at one end. Not applicable to -2 component. UVR-6110 (trade name, manufactured by Union Carbide Co.) is 3,4-epoxycyclohexylmethyl-3 ′, 4′-epoxycyclohexanecarboxylate, and corresponds to the component A-2 of the present invention. Also,
Rigarite 1125 (manufactured by Hercules) is a hydrogenated petroleum resin having a softening point of about 125 ° C. GI-1000 used in Examples 9 and 10 is a hydrogenated polybutadiene having a molecular weight of 1000 and having hydroxyl groups at both ends. Using each of the above compositions, a pressure-sensitive adhesive sheet was prepared on a polymer for viscoelasticity measurement and a PET film in the same manner as in Example 1.
However, in Comparative Example 2, since each component of the composition had a high viscosity, the components other than the photolatent initiator were dissolved at 100 ° C, and then the photolatent initiator was dissolved at 80 ° C. In order to reduce the viscosity when forming a pressure-sensitive adhesive sheet on a PET film and a polymer for measuring viscoelasticity, the viscosity is further reduced by 80%.
When the heating at ℃ was continued, a clear increase in viscosity was observed. Therefore, the other evaluations were interrupted, and only the viscosity measurement was performed immediately after the initiator was dissolved.

[0057]

[Table 1]

The viscosities of the compositions prepared in Examples 1 to 10 and Comparative Examples 1 and 2, the glass transition temperature and viscoelastic properties of the polymer, and the adhesive properties (adhesive strength,
Holding force and probe tack) were measured by the following method. Table 2 shows the measurement results of the viscosity and viscoelasticity, and Table 3 shows the measurement results of the adhesive properties. However, in Comparative Example 2, since the viscosity was increased as described above, only the viscosity measurement results are shown.

(1) Viscosity measurement: The viscosity of the composition after compounding was 2
It measured at 5 degreeC with the E-type viscometer. (2) Measurement of viscoelasticity: The complex elastic modulus of the cationic polymer of the composition was measured using a 1 mm thick polymer as RDSI manufactured by Rheometrics.
It was measured by shear shear stress using a type I viscoelasticity measuring device. (3) Glass transition temperature: JIS K
The measurement was performed by the DSC method specified in 7121. (4) Adhesion: Measured by the method described in JIS Z-0237. After cutting the adhesive sheet to a width of 25 mm, the sheet is bonded to an adherend (SUS plate or polyethylene (PE) plate) so that the adhesive area is 25 mm × 100 mm.
One pressure reciprocation press with a kg roll. The 180 degree peel strength was measured under the conditions of 23 ° C. and 65% RH. Also, observe the pressure-sensitive adhesive phase remaining on the adherend after the peel strength measurement,
When the form of peeling is interfacial peeling, it is defined as A, and when the adhesive remains on the adherend, it is determined that cohesive failure has occurred and C is determined.
It was determined.

(5) Holding force: A sample (25 mm width) cut from an adhesive sheet was bonded to a SUS plate with an adhesive area of 25 mm.
× 25 mm, and reciprocally pressed with a 2 kg roll. At 40 ° C. and 100 ° C., a load of 1 kg weight was applied to measure the time required for peeling off, and the holding time was defined as the holding force. In the case where it was held after 24 hours, the holding time was set to 24 hours or more, and the value obtained by measuring the deviation width from the initial bonding position was also shown. In addition, for the sample that peeled off within 24 hours in the main measurement, the pressure-sensitive adhesive phase remaining on the adherend after the measurement was observed. When the pressure-sensitive adhesive remained on the sample, it was determined to be C in which cohesive failure occurred. (6) SAFT: An adhesive sample of a SUS plate was prepared in the same manner as in the above-mentioned holding force measurement, and a load of 500 g weight was applied to the oven to increase the temperature from room temperature to 205 ° C. in an oven at a rate of 0.4 ° C./minute. The temperature at the time when the temperature rose and peeled off was measured. If the temperature is maintained after reaching 205 ° C.,
° C or higher, and the value obtained by measuring the width of deviation from the initial bonding position is also shown. Also, for samples that have come off,
The remaining pressure-sensitive adhesive phase was measured in the same manner as in the above holding power. (7) Probe tack: As described in ASTM D2979, probe tack was measured under the following conditions. Probe: SUS Diameter 5 mmΦ # 400 polished surface Load: 100 g / cm ² Contact time: 1 second Probe speed: 1 cm / sec Five measurements were performed for one sample, and the average value was shown.

[0061]

[Table 2]

[0062]

[Table 3]

As shown in Table 2, the compositions of Examples 1 to 10 and Comparative Example 1 had low viscosities, and were easy to apply even in the preparation of an adhesive sheet. In contrast, the composition of Comparative Example 2 had a high viscosity and was difficult to be applied at room temperature, and when heated for lowering the viscosity, it was apparently considered to be polymerization due to insufficient thermal stability. Thickening occurred. Further, as shown in Table 2, in the case of the composition of Comparative Example 1 in which the complex elastic modulus at 100 Hz in the viscoelastic properties of the polymer deviated from the range defined as preferable in the present invention, the tack value was significantly reduced. As a result, the adhesive strength is also low.

As is apparent from Table 3 above, Examples 1 to
All of the compositions shown in No. 10 show excellent adhesive properties,
In particular, it can be seen that the adhesive is excellent in holding power.
All of the forms of peeling were interfacial peeling, and no adhesive remained on the adherend. As is clear from the above results, the composition satisfying the viscosity and viscoelastic properties defined as preferable in the present invention can be easily applied to a substrate at room temperature, and the polymer after cationic polymerization shows good adhesive properties. It became clear. Further, it was revealed that the compositions having a complex elastic modulus at 100 ° C. (measurement frequency: 0.1 Hz) of more than 100,000 shown in Examples 2 and 3 were particularly excellent in holding power at high temperatures.

[0065]

Industrial Applicability The cationically polymerizable liquid composition of the present invention can be easily applied to a substrate without containing a solvent, and is used as an adhesive showing good adhesive properties by applying light or heat after application. It is possible. As a substitute for the existing solvent-based pressure-sensitive adhesive, its use as a novel pressure-sensitive adhesive that does not require removal of an organic solvent or the like can be greatly expected.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C09J 157/02 C09J 157/02 163/00 163/00 171/02 171/02 193/04 193/04 F Term (Reference) 4J002 AF02X BA00X BA01X BN00X CD02W CD05W CD06W CD17W CD18W EB117 EL026 EL056 EL066 EN137 EQ017 EV297 EW177 EZ007 FD157 FD34X GJ01 4J036 AD08 AF06 AJ08 AK01 AK03 FA10 FA11 GA01 GA03 EC01 GA01 GA01 GA04 EC221 EE021 EE031 HC14 HD13 HD43 JA01 JB09 KA11 KA12 KA13 KA26 LA06

Claims (17)

[Claims] 1. A monofunctional monomer having only one cyclic ether structure represented by the following formula (1) in a molecule (A-
1) Cationic polymerization containing a polyfunctional monomer (A-2) having two or more cyclic ether structures represented by the following formula (1) in a molecule and a cationic polymerization initiator having potential (A-3) And a solid resin (B) compatible with the compound (A) at room temperature and having a softening point of 40 ° C. or more, and having a viscosity of 20P at 25 ° C.
A cationically polymerizable liquid composition characterized by a · sec or less. Embedded image In the formula (1), n represents 0, 1 or 2, and R _{1 to} R ₆ each represent a hydrogen atom or a hydrocarbon group which may have a substituent. 2. The cationically polymerizable liquid composition according to claim 1, wherein at least one of R _{1 to} R ₆ in the formula (1) is a substituent represented by the following formula (2). Embedded image In the formula (2), R ₇ and R _{8 each} represent a hydrogen atom or an alkyl group which may have a substituent, and R ₉ represents a linear or branched alkyl group having 4 or more carbon atoms. , X is an oxygen atom or -CH ₂ - shows a. 3. The monofunctional monomer (A-1) is represented by the formula (1)
3. The cationically polymerizable liquid composition according to claim 1, wherein the oxetane is an oxetane wherein n = 1. 4. The monofunctional monomer (A-1) is represented by the formula (3)
The cationically polymerizable liquid composition according to any one of claims 1 to 3, which is represented by the formula: Embedded image In the formula (3), R ₇ , R ₈ and R ₁₀ represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms which may have a substituent, and R ₉ represents a straight chain having 4 to 24 carbon atoms. Represents a branched or branched alkyl group, and X represents an oxygen atom. 5. The polyfunctional monomer (A-2) is an epoxy resin containing two or more epoxy groups.
The cationically polymerizable liquid composition according to any one of the above. 6. The cationically polymerizable liquid composition according to claim 1, wherein the polyfunctional monomer (A-2) contains two or more alicyclic epoxy groups. 7. The cationically polymerizable liquid composition according to claim 1, wherein the polyfunctional monomer (A-2) contains two or more oxetanyl groups. 8. The method according to claim 8, wherein the polyfunctional monomer (A-2) is 3,4-
The cationically polymerizable liquid composition according to any one of claims 1 to 7, which is epoxycyclohexylmethyl-3 ', 4'-epoxycyclohexanecarboxylate. 9. The cationic polymerization type liquid composition according to claim 1, wherein the cationic polymerization initiator (A-3) is photolatent or heat latent. 10. The cationically polymerizable liquid composition according to claim 1, wherein the solid resin (B) is a hydrogenated petroleum resin and / or a hydrogenated rosin-based resin. 11. The cationically polymerizable liquid composition according to claim 1, which has a hydroxyl group at at least one molecular terminal and contains a monool or polyol compound having a molecular weight of 300 to 10,000. . 12. The cationically polymerizable liquid composition according to claim 1, wherein the complex elastic modulus (G ^* ) at 25 ° C. of the polymer after cationic polymerization satisfies the following condition. At 25 ° C., G ^* > 100,000 (measuring frequency: 0.1 Hz) G ^* <4,000,000 (measuring frequency: 1 Hz) G ^* > 2,000,000 (measuring frequency: 100H)
z) 13. The polymer obtained after cationic polymerization at 100 ° C.
The cation polymerization type liquid composition according to any one of claims 1 to 12, wherein a complex elastic modulus (G ^* ) in the above satisfies the following conditions. G ^* > 100,000 (measurement frequency: 0.1 Hz) 14. The loss tangent (Tan δ) at 25 ° C. of the polymer after cationic polymerization is 0.8 (measurement frequency: 100
Hz) or higher, the cationically polymerizable liquid composition according to any one of claims 1 to 13. 15. The cationically polymerizable liquid composition according to claim 1, wherein the glass transition temperature of the polymer after the cationic polymerization is 0 ° C. or lower. 16. A monofunctional monomer having only one cyclic ether structure represented by the following formula (1) per molecule (A-
1) Cationic polymerization containing a polyfunctional monomer (A-2) having two or more cyclic ether structures represented by the following formula (1) in a molecule and a cationic polymerization initiator having potential (A-3) And a solid resin (B) compatible with the compound (A) at room temperature and having a softening point of 40 ° C. or more, and having a viscosity of 20P at 25 ° C.
An adhesive polymer obtained by cationically polymerizing a cationically polymerizable liquid composition having a · sec or less. Embedded image In the formula (1), n represents 0, 1 or 2, and R _{1 to} R ₆ each represent a hydrogen atom or a hydrocarbon group which may have a substituent. 17. The polymer 2 obtained by cationic polymerization.
The adhesive polymer according to claim 16, wherein the complex elastic modulus (G ^* ) at 5 ° C and 100 ° C satisfies the following condition. 25 ° C
G ^* > 100,000 (measurement frequency: 0.1 Hz) G ^* <4,000,000 (measurement frequency: 1 Hz) G ^* > 2,000,000 (measurement frequency: 100H
z) and at 100 ° C., G ^* > 100,000 (measuring frequency: 0.1 Hz)