TWI472590B - Cationic polymerizable adhesive and polarizing plate obtained by using the same - Google Patents

Description

Cationic polymerizable adhesive and polarizing plate obtained using same

The present invention relates to a cationically polymerizable adhesive which can be used for various applications mainly including optical members such as polarizing plates.

In general, it is known that a polarizing plate used as a liquid crystal display or the like is formed on a polarizing plate formed of a polyvinyl alcohol-based film impregnated with a dichroic material such as iodine, and the laminate is saturated with triethylenesulfide cellulose or thermoplastic. A polarizing plate of a transparent protective film formed of a terpene resin or the like. For the adhesive used for the polarizer and the protective film, the industry demands excellent normal bonding strength for the two adhesives of the polarizer and the protective film, and is also not affected by the backlight of the liquid crystal display. By the influence of light or heat, the excellent normal bonding strength to the polarizer and the protective film can be maintained for a long period of time.

On the other hand, in recent years, a cationically polymerizable adhesive as an adhesive has been attracting attention, and it is difficult to cause hardening inhibition due to oxygen in the air, and it is possible to perform a hardening reaction even after stopping the supply of energy such as ultraviolet rays. The application of the polarizer and the protective film to the subsequent use has also begun to be explored.

For example, an adhesive for the adhesive of the polarizer and the protective film is known, and an adhesive formed of a composition containing an epoxy resin containing no aromatic ring as a main component is specifically known to contain a hydrogenated epoxy. A resin, an alicyclic epoxy resin, or an adhesive of an aliphatic epoxy resin and a photocationic polymerization initiator (for example, refer to Patent Document 1).

However, the normal bonding strength of the polarizer formed of the polyvinyl alcohol or the like of the adhesive is still different from the level required by the industry, and is affected by light or heat caused by a backlight or the like. The resulting normal bonding strength decreases with time, and has a situation in which the polarizing film and the protective film are peeled off in a short period of time.

In this way, with the development competition of liquid crystal displays that can display more vivid images, various optical characteristics are also required for the optical components constituting the liquid crystal display, and in fact, it has not been found that long-term retention can be used for polarizers and protection. A superior cationic, subsequently strength, cationically polymerizable adhesive for subsequent use of the film.

Patent Document 1: Japanese Patent Laid-Open Publication No. 2004-245925

An object of the present invention is to provide a cationically polymerizable adhesive which can maintain excellent normal bonding strength for a long period of time without being affected by heat, light, or the like, and a polarizing plate obtained by using the adhesive followed by a polarizer and a protective film.

In order to solve the above problems, the inventors of the present invention have studied various compounds known as cationically polymerizable compounds such as a hydroxyl group-containing compound, an oxetane group-containing compound, and an alicyclic epoxy compound. combination.

Specifically, an adhesive which combines a lower molecular weight oxetane group-containing compound, an aromatic epoxidized propyl ether, and a photocationic polymerization initiator is considered, and in such an adhesive, the normal state over time is sufficiently prevented. Subsequent reduction in strength is difficult.

Therefore, the inventors of the present invention have found that a specific combination of the above cationically polymerizable compounds is also combined with various amounts of residual chlorine which may be contained in the obtained adhesive, and it is found that a low molecular weight oxetane compound is contained. Among the binders of the aromatic epoxy propyl ether and the photocationic polymerization initiator, the binder remaining in the total amount of the binder is 1500 ppm or less, which can solve the problem of the present invention.

That is, the present invention relates to a cationically polymerizable adhesive and a polarizing plate obtained by using the same, and the adhesive includes an oxetane compound having a molecular weight of 100 to 800 having two or more oxetanyl groups. (A), an aromatic epoxy propyl ether (B), and an adhesive for a cationic polymerization initiator (C), characterized in that the amount of chlorine remaining in the total amount of the adhesive is 1,500 ppm or less.

Since the cationically polymerizable adhesive of the present invention is not affected by heat, light, or the like, it is possible to find an optical material or a building material such as a polarizing plate or an adhesive for an automobile interior and exterior decorative part, which is excellent in normal bonding strength over a long period of time. In addition, since the cationically polymerizable adhesive of the present invention has a good normal bonding strength to a polyvinyl alcohol film used for a general polarizing material, it can be used exclusively for the production of a polarizing plate, and is particularly suitable for a polarizing mirror and a protective film constituting a polarizing plate. This is followed by possible.

[Embodiment of the Invention]

The present invention is an oxetane compound (A) having a molecular weight of 100 to 800 having two or more oxetanyl groups, an aromatic epoxy propyl ether (B), and a cationic polymerization initiator (C) a cationically polymerizable adhesive containing 1,500 ppm or less of chlorine remaining in the total amount of the adhesive, if necessary, and which is suitable for the polarizing plate constituting the polarizing plate and The protective film is followed. Further, the molecular weight is determined by calculation based on the amount of the formula.

The oxetane compound (A) used in the present invention is important to use a compound having a molecular weight of from 100 to 800. In order to sufficiently cure the polarizer and the protective film, the film thickness of the adhesive layer is usually used by a film (a few μm thick). In order to apply the adhesive uniformly to the film thickness, the adhesive must be Low viscosity. Moreover, in order to obtain the low viscosity adhesive, it is necessary to use the above lower molecular weight oxetane compound. An adhesive obtained by substituting the oxetane compound (A) with, for example, an oxetane compound having a molecular weight of about 1,500, has a high viscosity, is difficult to be thinned, and causes the adhesive layer to be hardenable. The decrease or the subsequent decrease in strength.

The oxetane compound (A) is more preferably used to have a molecular weight in the range of 100 to 500, and is particularly preferably used, from the viewpoint of further improving the coating workability or the curability of the cationically polymerizable adhesive of the present invention. A molecular weight in the range of 150 to 400.

Further, the oxetane compound (A) is one which has two or more oxetane ring structures which contribute to cationic polymerization, and preferably has from 2 to 4, and imparts good hardenability and normal state. Better in strength.

Specifically, the oxetane compound (A) used in the present invention can be used alone or in combination of two or more kinds, for example, the compounds represented by the following formulas (1) and (2).

R ₁ in the above formulas (1) and (2) represents a hydrogen atom independently selected from a straight chain, a branched chain or a cyclic alkyl group having 1 to 6 carbon atoms, an allyl group or an aryl group. An aralkyl group, a furyl group or a thiol group, R ₂ represents a respective independent divalent organic residue, and Z represents an independent oxygen atom or a sulfur atom.

The linear, branched or cyclic alkyl group having 1 to 6 carbon atoms represented by R ₁ in the general formulae (1) and (2) is, for example, a methyl group, an ethyl group, a normal or an isopropyl group. a butyl group, a benzyl group, a benzyl group, a hexyl group, a cyclohexyl group, etc.; Phenylethyl and the like.

Further, the divalent organic residue represented by R ₂ in the above formula (1) may, for example, be a linear, branched or cyclic alkyl group having a polycondensation of 4 to 30 carbon atoms. (Strongoxane) group, phenylene group, xylylene group, and structures represented by the following formulas (3) and (4).

The linear, branched chain or cyclic alkyl group constituting R ₂ in the formula (1) is preferably a methylene group or an ethylidene group 1,2- or 1,3-propanyl group. A butyl group, a cyclohexyl group or the like having an alkyl group having 1 to 15 carbon atoms. Further, the poly(oxyalkylene) group having 4 to 30 carbon atoms is preferably a group having 4 to 8 carbon atoms, and for example, a poly(extended ethoxy) group or a poly(oxypropylene) group is preferred.

R ₃ in the formula (3) represents an oxygen atom, a sulfur atom, CH ₂ , NH, SO, SO ₂ , C(CF ₃ ) ₂ or C(CH ₃ ) ₂ .

R ₄ in the formula (4) represents an alkylene group having 1 to 6 carbon atoms, an extended aryl group, and a functional group represented by the following formula (5).

In the general formula (5), a represents an integer of 1 to 6, and b represents an integer of 1 to 15.

b is preferably an integer of from 1 to 3 as the general formula (5).

An oxetane compound having the structure of 2 to 4 oxetane rings, for example, Aron Oxetane OXT-221, Aron Oxetane OXT-121, Aron Oxetane OXT-223 (hereinafter, Japan East Asia Synthetic Co., Ltd.) )), Eternacoll OXBP (hereinafter, the Japanese word production company).

The oxetane compound (A) is preferably one represented by the formula (1), and in particular, in the formula (1), R ₁ is an ethyl group and R ₂ is a methylene group [1- Ethyl (3-oxetanyl) methyl ether is capable of improving the curability of the adhesive after thinning and hardening, and is capable of preventing heat or light due to long-term prevention. It is then preferred to reduce the strength.

Further, in the present invention, in addition to the oxetane compound (A) having the two or more oxetane ring groups, an oxygen hetero ring having one oxetane ring group may be combined as necessary. When the butane compound (D) is used, it is possible to ensure a sufficient open time by bonding the polarizer and the protective film, and the polarizing plate obtained by preventing the bonding for a long period of time is caused by peeling of heat or light. The point of view is better. In particular, the oxetane compound (A) has an equivalent ratio of the oxetane group to the oxetanyl group of the oxetane compound (D) [(A) has an oxa compound The cyclobutane/(D) has an oxetane group preferably used in the range of 0.1 to 35.0, more preferably in the range of 0.2 to 10.0, particularly preferably in the range of 1 to 5.

In addition, as the oxetane compound (D) having the one oxetanyl group, for example, a compound represented by the following formula (6) can be used.

(R ₁ in the formula (6) represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an alkoxyalkyl group having 1 to 5 carbon atoms, or a hydroxyalkyl group having 1 to 6 carbon atoms. R ₂ represents a hydrogen atom, a branched alkyl group having 1 to 10 carbon atoms, an aliphatic cyclic structure, and an aromatic structure.

Examples of the alkyl group having 1 to 8 carbon atoms of R ₁ in the above formula (6) include a methyl group, an ethyl group, a n-propyl group, an isopropyl group, and a 2-ethylhexyl group.

Further, examples of the alkoxyalkyl group having 1 to 5 carbon atoms of R ₁ in the above formula (6) include methoxymethyl group, ethoxymethyl group, propoxymethyl group and methoxyethyl group. Base, ethoxyethyl, propoxyethyl and the like.

In addition, examples of the hydroxyalkyl group having 1 to 6 carbon atoms of R ₁ in the above formula (6) include a methylol group, a hydroxyethyl group, and a hydroxypropyl group.

Further, the branched alkyl group having 1 to 10 carbon atoms which may constitute R ₂ in the above formula (6) may, for example, be a linear alkyl group such as a methyl group or an ethyl group or a propyl group, or the like. A branched alkyl group of 2-ethylhexyl or the like.

Moreover, the aliphatic ring structure which can constitute R ₂ in the above formula (6), for example, a cyclohexyl group or the like can be mentioned. The cyclohexyl group or the like may have an alkyl group or the like which substitutes a hydrogen atom.

Further, the aromatic structure of R ₂ in the above formula (6) can be exemplified, and examples thereof include a phenyl group. The phenyl group or the like may have an alkyl group or the like which substitutes a hydrogen atom.

The oxetane compound (D) is preferably used having a molecular weight of from 100 to 500, more preferably from 150 to 500.

Further, the oxetane compound (D) is more preferably used from 3-hydroxymethyl-3-ethyloxetane or 3-ethyl-3-(phenoxymethyl)oxycyclohexane. a group consisting of butane, 3-ethyl-3-(2-ethylhexyloxymethyl)oxetane and 3-ethyl-3-(cyclohexyloxy)methyloxetane One or more selected from the group.

In the present invention, the oxetane compounds (A) and (D) are preferably used in an amount of from 20 to 70% by mass based on the total amount of the cationically polymerizable adhesive. Further, the total amount of the oxetane compound (A) and (D) is preferably from 20 to 70% by mass as the double [1-B of the oxetane compound (A). (3-oxetanyl)methyl ether, and is preferably used in combination of 20 to 70% by mass based on the total amount of the oxetane compounds (A) and (D). The 3-hydroxymethyl-3-ethyloxetane of the oxetane compound (D) can prevent an improvement in hardenability and a decrease in adhesion strength due to heat or light for a long period of time.

Next, the aromatic epoxy propyl ether (B) used in the present invention will be described.

In the present invention, an aromatic epoxidized propyl ether (B) which is opened by a cationic polymerization initiator (C) to be described later and which forms a crosslinked structure, is used.

The aromatic epoxy propyl ether (B) can be bisphenol A type epoxy propyl ether, bisphenol F type epoxy propyl ether, bisphenol S type epoxy propyl ether or bisphenol AD type propylene propylene The ether is preferably a bisphenol A type epoxy propyl ether or a bisphenol F type epoxy propyl ether.

It is preferable to use bisphenol A type epoxidized propyl ether or bisphenol F type from the viewpoint of further improving the curability of the cationically polymerizable adhesive of the present invention and preventing the decrease in the adhesion strength due to heat or light for a long period of time. A epoxidized propyl ether in which a bisphenol A type diepoxypropyl ether or a bisphenol F type diepoxypropyl ether is particularly preferable is particularly preferable.

It is preferred to use a compound having two or more epoxy propyl ether groups, more preferably 2 to 6 epoxy propyl groups, based on imparting a good normal bonding strength. Ether based.

Further, the aromatic epoxidized propyl ether (B) can be produced by reacting bisphenol A or bisphenol F with epichlorohydrin or the like, and is caused by the obtained aromatic epoxy propyl ether. The chlorine system such as epichlorohydrin has a part of the chlorine remaining. Further, in the commercially available glycidyl propyl ether group-containing compound, usually, about 8% to 10% by weight of chlorine is contained.

Therefore, when the aromatic epoxidized propyl ether (B) is produced, the treatment for removing chlorine or the like is performed by rectification or the like, and the viewpoint of imparting further excellent normal bonding strength and preventing discoloration of the polarizing mirror is considered. Preferably. The rectification is preferably carried out at a temperature of, for example, about 50 to 200 ° C for about 1 to 200 hours. Further, the amount of chlorine remaining in the aromatic epoxy propyl ether (B) can be measured in accordance with JIS K 1200-3-2:00.

The aromatic epoxidized propyl ether (B) is preferably contained in an amount of 5 to 50% by mass based on the total amount of the cationically polymerizable adhesive agent of the present invention, and is excellent in normal strength for a long period of time, and more preferably 10%. ～40% by mass.

Further, in the present invention, in addition to the aromatic epoxy propyl ether (B), other epoxy propyl ethers may be used as necessary.

As the other epoxy propyl ether, for example, trimethylolpropane triepoxypropyl ether, glycerol triepoxypropyl ether, polyglyceryl triepoxypropyl ether, diglycerin triepoxypropyl ether, or the like can be used. An aliphatic epoxy propyl compound (a1) having three epoxypropyl ether groups, or trimethylolpropane diepoxypropyl ether, 1,6-hexanediol diepoxypropyl ether, 1 , 4-butanediol diepoxypropyl ether, cyclohexane dimethanol diepoxypropyl ether, propylene glycol diepoxypropyl ether, diethylene glycol diepoxypropyl ether, etc. having 2 epoxy A propyl ether based epoxy propyl compound.

Further, the other epoxy propyl ether can also be hydrogenated hydrogenated bisphenol A type epoxy propyl ether or hydrogenated bisphenol F type epoxy propyl ether of the aromatic epoxidized propyl ether (B). Other aromatic epoxy propyl ethers.

Next, the cationic polymerization initiator (C) used in the present invention will be described.

The cationic polymerization initiator (C) used in the present invention is a photocationic polymerization initiator which generates an acid capable of initiating cationic polymerization by irradiation with an energy ray such as ultraviolet rays, or heat which generates acid by heating. Cationic polymerization initiator. Among them, in the case where a polarizing plate is produced by a polarizer and a protective film, or in the case of manufacturing another optical material, a photocationic polymerization initiator is preferably used from the viewpoint of preventing deformation or discoloration of the substrate due to heat.

The photocationic polymerization initiator, for example, a cationic moiety is an aromatic hydrazine, an aromatic iodonium, an aromatic diazonium, an aromatic ammonium, a thiopurine, or a 9-oxosulfur 鎓, (2,4-cyclopentadien-1-yl)[(1-methylethyl)benzene]-Fe cation, an anion moiety can be used alone from BF ₄ ^- , PF ₆ ^- , SbF ₆ ^- , [ BX ₄ ] ^- (However, X is a phenyl group substituted with at least two or more fluorine or a trifluoromethyl group) or two or more kinds thereof may be used in combination.

The aromatic onium salt can use, for example, bis[4-(diphenyldihydrothio)phenyl]thioether bishexafluorophosphate, bis[4-(diphenyldihydrothio)phenyl]thioether Bis(hexafluoroantimonate), bis[4-(diphenyldihydrothio)phenyl]thioether bistetrafluoroborate, bis[4-(diphenyldihydrothio)phenyl]thioether (pentafluorophenyl)borate, diphenyl-4-(phenylthio)phenylphosphonium hexafluorophosphate, diphenyl-4-(phenylthio)phenylphosphonium hexafluoroantimonate, diphenyl 4-(phenylthio)phenylphosphonium tetrafluoroborate, diphenyl-4-(phenylthio)phenylphosphonium tetrakis(pentafluorophenyl)borate, triphenylsulfonium hexafluorophosphate, Triphenylsulfonium hexafluoroantimonate, triphenylsulfonium tetrafluoroborate, triphenylsulfonium tetrakis(pentafluorophenyl)borate, bis[4-(bis(4-(2-hydroxyethoxy)) Phenyldihydrothio)phenyl]thioether bishexafluorophosphate, bis[4-(bis(4-(2-hydroxyethoxy))phenyldihydrothio)phenyl]thioether double Hexafluoroantimonate, bis[4-(bis(4-(2-hydroxyethoxy))phenyldihydrothio)phenyl]thioether bistetrafluoroborate, bis[4-(di(4) -(2-Hydroxyethoxy))phenyldihydrothio)phenyl]thioether tetrakis(pentafluorophenyl)borate.

Further, as the aromatic iodonium salt, for example, diphenyliodonium hexafluorophosphate, diphenyliodonium hexafluoroantimonate, diphenyliodonium tetrafluoroborate, diphenyliodonium tetrachloride (five) can be used. Fluorophenyl)borate, bis(dodecylphenyl)iodonium hexafluorophosphate, bis(dodecylphenyl)iodonium hexafluoroantimonate, bis(dodecylphenyl)iodine Tetrafluoroborate, bis(dodecylphenyl)iodonium tetrakis(pentafluorophenyl)borate, 4-methylphenyl-4-(1-methylethyl)phenyliodonium hexafluoro Phosphate, 4-methylphenyl-4-(1-methylethyl)phenyliodonium hexafluoroantimonate, 4-methylphenyl-4-(1-methylethyl)phenyl iodide Tetrafluoroborate, 4-methylphenyl-4-(1-methylethyl)phenyliodonium tetrakis(pentafluorophenyl)borate, and the like.

Further, as the aromatic diazonium salt, for example, phenyldiazonium hexafluorophosphate, phenyldiazonium hexafluoroantimonate, phenyldiazonium tetrafluoroborate, or phenyldiazonium can be used. Pentafluorophenyl) borate, and the like.

Further, as the aromatic ammonium salt, 1-benzyl-2-cyanopyridinium hexafluorophosphate, 1-benzyl-2-cyanopyridinium hexafluoroantimonate, 1-benzyl-2-cyanide can be used. Pyridinium tetrafluoroborate, 1-benzyl-2-cyanopyridinium tetrakis(pentafluorophenyl)borate, 1-(naphthylmethyl)-2-cyanopyridinium hexafluorophosphate, 1- (naphthylmethyl)-2-cyanopyridinium hexafluoroantimonate, 1-(naphthylmethyl)-2-cyanopyridinium tetrafluoroborate, 1-(naphthylmethyl)-2-cyanopyridine Tetrakis(pentafluorophenyl)borate and the like.

In addition, the 9-oxygen sulfur Strontium salt can use S-biphenyl-2-isopropyl-9-oxosulfur Hexafluorophosphate and the like.

Further, the (2,4-cyclopentadien-1-yl)[(1-methylethyl)benzene]-Fe salt can be used (2,4-cyclopentadien-1-yl) [(1) -methylethyl)benzene]-Fe(II) hexafluorophosphate, (2,4-cyclopentadien-1-yl)[(1-methylethyl)benzene]-Fe(II) hexafluoro Citrate, (2,4-cyclopentadien-1-yl)[(1-methylethyl)benzene]-Fe(II) tetrafluoroborate, (2,4-cyclopentadiene-1 -yl)[(1-methylethyl)benzene]-Fe(II)tetrakis(pentafluorophenyl)borate.

The photocationic polymerization initiator is commercially available, for example, as CPI-100P, CPI-101A, CPI-200K (above, manufactured by SAN-APRO Co., Ltd.); CYRACURE photohardening initiator UVI-6990, CYRACURE photohardening initiator UVI-6992 CYRACURE Photohardening Initiator UVI-6976 (above, DOW CHEMICAL Japan Co., Ltd.); ADEKA OPTMER SP-150, ADEKA OPTMER SP-152, ADEKA OPTMER SP-170, ADEKA OPTMER SP-172 ADEKA OPTMER SP-300 ( Above, (share) ADEKA system); CI-5102, CI-2855 (above, Japan Soda (manufactured by the company)); SAN-AID SI-60L, SAN-AID SI-80L, SAN-AID SI-100L, SAN- AID SI-110L, SAN-AID SI-180L, SAN-AID SI-110, SAN-AID SI-180 (above, manufactured by Nippon Sanken Chemical Co., Ltd.); ESACURE 1064, ESACURE 1187 (above, LAMBERT) OMNICAT 550 (manufactured by IGM RESIN); IRUGACURE 250 (manufactured by CIBA SPECALITY CHEMICALS); RHODOSAIL PHOTOINITIATOR 2074 (manufactured by RHODIA JAPAN Co., Ltd.).

Further, as the thermal cationic polymerization initiator, for example, benzamidine salt, thiophene sulfonium salt, tetrahydrothiophene sulfonium salt, benzylammonium salt, pyridinium salt, or the like can be used. Salts, carboxylates, sulfonates, amines, and the like.

For the thermal cationic polymerization initiator, "ADEKA OPTON CP77", "ADEKA OPTON CP66" (above, ADEKA), "CI-2639", "CI-2624" can be used (above, Japan Soda Co., Ltd.) ), "SAN-AID SI-60L", "SAN-AID SI-80L", "SAN-AID SI-100L" (above, manufactured by Nippon Sanshin Chemical Industry Co., Ltd.).

The amount of the cationic polymerization initiator (C) to be used is not particularly limited, and is preferably from 0.1 to 20% by mass, more preferably from 1 to 15%, based on the total amount of the cationically polymerizable adhesive. The range of mass %.

Further, in the cationically polymerizable adhesive of the present invention, in addition to the oxetane compound (A), the aromatic epoxidized propyl ether (B), and the cationic polymerization initiator (C), it is necessary An alicyclic epoxy compound (E) or an epoxy group-containing decane compound (F) or the like may also be used in combination.

The alicyclic epoxy compound (E) is used to improve the adhesive strength at the initial stage of bonding, and is preferably used in the adhesive of the present invention in addition to preventing offset of the substrate.

The alicyclic epoxy compound (E) can use a plurality of alicyclic epoxy groups, and it is preferably used in an amount of 2 to 4.

Among the alicyclic epoxy compounds (E), as the alicyclic epoxy group of the two alicyclic epoxy groups, for example, 3,4-epoxycyclohexane represented by the following formula (7) can be used. Alkenylmethyl-3,4-epoxycyclohexanecarboxylate (a compound in which a is 0 in the formula (7)), a caprolactone-modified product thereof (in the formula (7), a a compound of 1), a modified trimethylcaprolactone (structural formula (8) and structural formula (9)), and a modified valerolactone thereof (structural formula (10) and structural formula (11) )) or a compound of the formula (12).

(a in the formula (7) represents 0 or 1.)

In addition, the alicyclic epoxy compound represented by the formula (12) is, for example, commercially available CYRACURE UVR-6128 (above, manufactured by DOW CHEMICAL Japan Co., Ltd.).

Further, among the oxetane compounds (D), an alicyclic epoxy compound having two alicyclic epoxy groups, and a compound represented by the following formula (13) can also be used.

(In the formula (13), R ₁ to R ₆ each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.)

Specific examples of the compound represented by the formula (13) include a dicyclohexyl-3,3'-diepoxide compound.

As the alicyclic epoxy compound having three alicyclic epoxy groups, a compound represented by the following formula (14) can be used.

In the formula (14), a and b are each independently 0 or 1, and these may be the same or different.

The alicyclic epoxy compound represented by the formula (14) is, for example, commercially available EPOLEAD GT301 or EPOLEAD GT302 (above, manufactured by DAICEL Chemical Industries Co., Ltd.).

As the alicyclic epoxy compound having four alicyclic epoxy groups, a compound represented by the following formula (15) can be used.

In the general formula (15), a to d are each independently 0 or 1, and these a to d may be the same or different.

The alicyclic epoxy compound represented by the formula (15) is, for example, commercially available EPOLEAD GT401 or EPOLEAD GT403 (above, manufactured by DAICEL Chemical Industries Co., Ltd.).

The alicyclic epoxy compound (E) is preferably used in an amount of from 1 to 20% by mass based on the total amount of the cationically polymerizable adhesive of the present invention, and is used in an amount of from 2 to 10% by mass. It is preferable to bond the initial strength at the initial stage and prevent the offset of the substrate.

In addition, the epoxy group-containing decane compound (F) is preferably used in the adhesive of the present invention by further improving the normal bonding strength of the obtained adhesive, and also particularly preventing discoloration of the polarizing lens. . When an amino decane such as 3-aminopropyltriethoxy decane or ethylene decane such as ethylene triethoxy decane is used, it is polarized in comparison with the case of using the compound (F). The discoloration prevention effect of the mirror will tend to be slightly reduced.

The epoxy group-containing decane compound (F) is preferably used, for example, 3-glycidoxypropyltrimethoxydecane, 3-glycidoxypropyltriethoxydecane, 3-glycidoxypropylmethyl Diethoxy decane, 3-glycidoxypropylmethyldimethoxydecane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxydecane, 2-(3,4- Epoxycyclohexyl)ethyltriethoxydecane, etc.; wherein 3-glycidoxypropyltriethoxydecane, 3-glycidoxypropyltrimethoxydecane, 2-(3) are used. One or more selected from the group consisting of 4-cyclooxycyclohexyl)ethyltrimethoxyphosphonium and 2-(3,4-epoxycyclohexyl)ethyltriethoxydecane, Further excellent normal bonding strength, while also preventing fading of the polarizing lens and the like is preferred.

Further, as the epoxy group-containing decane compound (F), a decane oil represented by the following formulas (16) and (17) can also be used.

(n in the above formula (16) represents an integer of 1 or more.)

(R in the above formula (16) represents an organic group, and n represents an integer of 1 or more.)

The epoxy group-containing decane compound (F) is used in an amount of 0.1 to 1.5% by mass based on the total amount of the cationically polymerizable adhesive of the present invention, and does not cause the subsequent strength due to the influence of heat or the like. It is preferable to reduce it and prevent fading of the polarizer or the like.

In the cationically polymerizable adhesive agent used in the present invention, the amount of chlorine remaining in the total amount of the cationically polymerizable adhesive agent is 1,500 ppm or less, and further, excellent heat-resistance strength is imparted, and discoloration of a polarizing mirror or the like is prevented. The view is very ideal. When the amount of chlorine exceeds 1,500 ppm, there is a case where the adhesive layer or the obtained polarizer is easily discolored or the strength is lowered.

Here, the term "chlorine" as used in the present invention refers to chlorine or chloride derived from a raw material such as epichlorohydrin used for the production of the aromatic epoxidized propyl ether (B), and an adhesive resulting from the present invention. Various additives which can be used in combination, such as inorganic chlorides such as sodium chloride.

The total amount of the cationically polymerizable adhesive is preferably 1500 ppm or less, more preferably 1000 ppm or less, more preferably 800 ppm or less, and fading such as a polarizer or the like and a long-term normal bonding strength. Will be possible. Further, the amount of chlorine remaining in the total amount of the cationically polymerizable adhesive of the present invention can be measured in accordance with JIS K 1200-3-2:00.

In particular, in order to further prevent discoloration of the polarizer or the like, it is preferred to use the epoxy group-containing decane compound (F) and to adjust the amount of chlorine remaining in the cationically polymerizable adhesive to 1500 ppm or less.

The method of adjusting the amount of chlorine remaining in the cationically polymerizable adhesive of the present invention to 1500 ppm or less is, for example, a method of removing chlorine by rectifying or using a capture material which can capture the chlorine. The rectification is preferably carried out at a temperature of, for example, about 50 to 200 ° C for about 1 to 200 hours.

The cationically polymerizable adhesive of the present invention can be produced, for example, by the following method.

The cationically polymerizable adhesive of the present invention is obtained by using, for example, a sealed planetary mixer or the like, the oxetane compound (A) and the aromatic epoxy propyl ether (B) which have been previously prepared in advance. a cationic polymerization initiator (C), and if necessary, an oxetanyl oxetane compound (D) or the alicyclic epoxy compound (E) or the epoxy group-containing decane The compound (F) can be produced by mixing and stirring. In the case of using the oxetane compound (D), the oxetane compounds (A) and (D) previously mixed may also be used.

The cationically polymerizable adhesive obtained by this method preferably has a viscosity of 100 mPa·s or less at 25 ° C from the viewpoint of minimizing the thickness of the formed underlayer. The viscosity is mainly obtained by using a diluent such as an oxetane compound or an alicyclic epoxy compound, or a low molecular weight and liquid substance as the aromatic epoxy propyl ether (B). Adjustment.

The cationically polymerizable adhesive of the present invention may contain various additives as necessary within the range which does not impair the effects of the present invention.

The additive can be used in combination with, for example, a rocking viscosity reducing agent, a sensitizer, various polyalcohols and other polyalcohols, a flat agent, an antioxidant, an adhesion-imparting agent, a wax, a heat stabilizer, a light stabilizer, and a firefly. Optical brightener, foaming agent, thermoplastic resin, thermosetting resin, organic solvent, conductivity imparting agent, antistatic agent, moisture permeability improver, water repellent, hollow foam, water-containing compound, difficult A fuel, a water absorbing agent, a moisture absorbent, a deodorant, a foam stabilizer, an antifoaming agent, an antifungal agent, a preservative, an algaecide, an anti-caking agent, an anti-hydrolysis agent, an organic and inorganic water-soluble compound, and the like.

As the rocking and viscosity reducing agent, for example, surface-treated calcium carbonate, finely divided cerium oxide, bentonite, zeolite or the like can be used.

In the case of using the various additives, the oxetane compound (A), the aromatic epoxidized propyl ether (B), and the cationic polymerization initiator are carried out using, for example, a sealed planetary mixer or the like. C) and, if necessary, mixing and stirring the alicyclic epoxy compound (D) or the epoxy group-containing decane compound (E), and mixing and mixing.

The cationically polymerizable adhesive of the present invention can be cured by irradiation with an energy ray such as ultraviolet rays.

The irradiation of the energy ray such as ultraviolet rays is preferably 50 to 5,000 mJ/cm ² , more preferably 100 to 3,000 mJ/cm ² , and particularly preferably 300 to 1,500 mJ/cm ² .

A known lamp such as a xenon lamp, a neon-mercury lamp, a metal halide lamp, a high pressure mercury lamp, a low pressure mercury lamp, or the like can be used as a source of ultraviolet rays. Further, the amount of ultraviolet irradiation was measured using a value measured in a wavelength region of 300 to 390 nm using UV CHECKER UVR-N1 (manufactured by Nippon Battery Co., Ltd.).

Further, if necessary, after the irradiation of the energy ray, the curing may be further accelerated by heating at about 40 to 80 °C.

Next, the polarizing plate of the present invention will be described.

In the polarizing plate of the present invention, the adhesive layer formed of the cationically polymerizable adhesive is interposed and the protective film and the polarizer are formed.

The protective film used for the production of the polarizing plate can be formed using a cellulose resin such as triacetonitrile cellulose, a resin having a cycloolefin structure, a norbornene resin, etc., from the viewpoint of improving the polarizing property and the durability. A film or a sheet-like material, preferably a cellulose-based resin such as triethyl cellulose.

The cellulose resin can use, for example, cellulose acetate, cellulose acetate propionate, cellulose acetate butyrate, cellulose acetate propionate butyrate, cellulose acetate phthalate, and nitric acid. For the cellulose or the like, it is possible to use these resins alone or in combination of two or more kinds thereof, and cellulose acetate is preferably used because it can obtain excellent mechanical properties and transparency.

Further, the polarizer is not particularly limited, and various polarizers can be used, for example, a hydrophilic polymer such as polyvinyl alcohol, partially methylalized polyvinyl alcohol, or an ethylene/vinyl acetate copolymer partial saponified product. a polyethylene material formed on a compound, which is obtained by adsorbing a dichroic material such as iodine or a dichroic dye, and uniaxially stretching the product, dehydrating the polyvinyl alcohol, or dehydrochlorinating the polyvinyl chloride. It is a matching film or the like. Among them, a film in which a polyvinyl alcohol-based film and a dichroic substance such as iodine are adsorbed is preferably used.

The thickness of the protective film used in the production of the polarizing plate of the present invention varies depending on the use to be used, and is preferably in the range of about 20 μm to 100 μm. Further, the thickness of the polarizer is usually preferably in the range of about 5 μm to 50 μm.

Further, in the polarizing plate of the present invention, the cationically polymerizable adhesive is applied onto the protective film, and then the amount of ultraviolet rays is applied to the coated surface, and then the polarizer is placed on/attached to the coated surface. And can be manufactured. In this case, the thickness of the adhesive layer formed of the cationically polymerizable adhesive is preferably as small as possible, for example, preferably 5 μm or less.

The polarizing plate of the present invention obtained by the above method can be used for, for example, a mobile communication terminal such as a mobile phone, or a member constituting a display such as a liquid crystal television, a personal computer, or a mobile game machine.

Hereinafter, the details will be further specifically described by way of examples and comparative examples.

[Modulation Example 1]

An isomer mixture of bisphenol F-type diepoxypropyl ether compound having a chlorine content of 3.5% obtained by distillation at 1.3 kPa and 185 ° C according to JIS K 1200-3-2:00 (B) '-6) Next, rectification was carried out under the conditions of 0.02 MPa and 70 ° C to obtain a glycidyl propyl ether group-containing compound (B-1) having a chlorine content of 600 ppm. Further, the chlorine content contained in the glycidyl ether group-containing compound (B-1) is 0.05% or more with respect to sodium chloride, and a value obtained by a Volhard (Wahard) improvement method is used; For the substance below 0.05%, the value determined by ion chromatography analysis is used. Further, the chlorine contents of the glycidyl propyl ether group-containing compound (B-2), (B'-3), and (B'-4) disclosed in the following Preparation Examples 2 to 3 were also obtained by the same method as described above. Determination.

[Modulation Example 2]

An isomer mixture of bisphenol A type di-epoxypropyl ether having a chlorine content of 3.5%, which was obtained by distillation at 1.3 kPa and 185 ° C according to JIS K 1200-3-2, followed by 0.02 The rectification was carried out under the conditions of MPa and 70 ° C to obtain a glycidyl propyl ether group-containing compound (B-2) having a chlorine content of 600 ppm.

[Modulation Example 3]

Cyclohexane dimethanol diglycidyl ether having a chlorine content of 6.5% obtained by distillation under conditions of 1.3 kPa and 185 ° C according to JIS K 1200-3-2, followed by 0.02 MPa and 70 ° C The distillation was successively carried out to obtain a glycidyl propyl group-containing compound (B'-3) having a chlorine content of 500 ppm, a glycidyl propyl group-containing compound (B'-4) having a chlorine content of 1000 ppm, and chlorine. The content of 10000 ppm of the glycidyl ether-containing compound (B'-5).

[Example 1]

In a closed planetary mixer, 20.0 parts by mass of a glycidyl propyl ether group-containing compound (B-1) and 20.0 parts by mass of a glycidyl propyl ether group-containing compound (B'-4) by mixing and stirring, Aron Oxetane 35.0 parts by mass of OXT-221 (bis[1-ethyl(3-oxetanyl))methyl ether) manufactured by Japan East Asia Synthetic Co., Ltd. and Aron Oxetane OXT-101 (made by Japan East Asia Synthetic Co., Ltd.) 25.0 parts by mass of -hydroxymethyl-3-ethyloxetane) and CPI-100P as a photocationic polymerization initiator (C) (diphenyl-4-(benzene) manufactured by SAN-APRO Co., Ltd. A cationically polymerizable adhesive (1) was prepared by dissolving 4 parts by mass of a solution of a propionate 50% by mass of thio)phenyl hexafluorophosphate. The chlorine content contained in the total amount of the obtained cationically polymerizable adhesive (1) obtained by the method described later was 247 ppm.

[Embodiment 2]

In a closed planetary mixer, 20.0 parts by mass of a glycidyl propyl ether-containing compound (B-1) and 20.0 parts by mass of a glycidyl propyl ether group-containing compound (B'-3) by mixing and stirring, Aron Oxetane 35.0 parts by mass of OXT-221 (bis[1-ethyl(3-oxetanyl))methyl ether) manufactured by Japan East Asia Synthetic Co., Ltd. and Aron Oxetane OXT-101 (made by Japan East Asia Synthetic Co., Ltd.) 25.0 parts by mass of -hydroxymethyl-3-ethyloxetane) and CPI-100P as a photocationic polymerization initiator (C) (diphenyl-4-(benzene) manufactured by SAN-APRO Co., Ltd. The cation-polymerizable adhesive (2) was prepared by dissolving 4 parts by mass of a propionate 50% by mass solution of thio)phenyl hexafluorophosphate. The chlorine content contained in the total amount of the obtained cationically polymerizable adhesive (2) was 219 ppm as determined by the method described later.

[Example 3]

In a sealed planetary mixer, 20.0 parts by mass of a glycidyl ether-containing compound (B-2) and 20.0 parts by mass of a glycidyl propyl ether group-containing compound (B'-3) by mixing and stirring, Aron Oxetane 35.0 parts by mass of OXT-221 (bis[1-ethyl(3-oxetanyl))methyl ether) manufactured by Japan East Asia Synthetic Co., Ltd. and Aron Oxetane OXT-101 (made by Japan East Asia Synthetic Co., Ltd.) 25.0 parts by mass of -hydroxymethyl-3-ethyloxetane) and CPI-100P as a photocationic polymerization initiator (C) (diphenyl-4-(benzene) manufactured by SAN-APRO Co., Ltd. The cation-polymerizable adhesive (3) was prepared by dissolving 4 parts by mass of a solution of a propionate 50% by mass of thio)phenylphosphonium hexafluorophosphate. The chlorine content contained in the total amount of the obtained cationically polymerizable adhesive (3) was 211 ppm as determined by the method described later.

[Example 4]

In a closed planetary mixer, 20.0 parts by mass of a glycidyl propyl ether-containing compound (B-1) and 20.0 parts by mass of a glycidyl propyl ether group-containing compound (B'-3) by mixing and stirring, Aron Oxetane 35.0 parts by mass of OXT-221 (bis[1-ethyl(3-oxetanyl))methyl ether) manufactured by Japan East Asia Synthetic Co., Ltd. and Aron Oxetane OXT-101 (made by Japan East Asia Synthetic Co., Ltd.) 25.0 parts by mass of -hydroxymethyl-3-ethyloxetane), KBE-403 as an epoxy group-containing decane compound (F) (3-glycidylpropyl group, manufactured by Shin-Etsu Chemical Co., Ltd., Japan) 0.5 parts by mass of triethoxy decane, and CPI-100P as a photocationic polymerization initiator (C) (diphenyl-4-(phenylthio)phenylphosphonium hexafluorophosphate manufactured by SAN-APRO Co., Ltd. The ester polymerizable adhesive (4) was prepared by dissolving 4 parts by mass of the ester propionate 50% by mass solution. The chlorine content contained in the total amount of the obtained cationically polymerizable adhesive (4) was 218 ppm as determined by the method described later.

[Example 5]

In a closed planetary mixer, 20.0 parts by mass of a glycidyl propyl ether-containing compound (B-1) and 20.0 parts by mass of a glycidyl propyl ether group-containing compound (B'-3) by mixing and stirring, Aron Oxetane 25.0 parts by mass of OXT-221 (bis[1-ethyl(3-oxetanyl))methyl ether) manufactured by Japan East Asia Synthetic Co., Ltd. and Aron Oxetane OXT-101 (made by Nippon Biosynthetics Co., Ltd. 3 -hydroxymethyl-3-ethyloxetane) 30.0 parts by mass of CELLOXIDE 2021P as an alicyclic epoxy compound (E) (3,4-epoxycyclohexane manufactured by DAICEL Chemical Industry Co., Ltd.) 5.0 parts by mass of alkenylmethyl-3',4'-epoxycyclohexanecarboxylate), and CPI-100P as a photocationic polymerization initiator (C) (diphenyl produced by SAN-APRO Co., Ltd.) A cationically polymerizable adhesive (5) was prepared by dissolving 4 parts by mass of a solution of a propionate 50% by mass of thio-4-(phenylthio)phenylphosphonium hexafluorophosphate. The chlorine content contained in the total amount of the obtained cationically polymerizable adhesive (5) was determined to be 209 ppm by the method described later.

[Embodiment 6]

In a closed planetary mixer, 20.0 parts by mass of a glycidyl propyl ether-containing compound (B-1) and 20.0 parts by mass of a glycidyl propyl ether group-containing compound (B'-3) by mixing and stirring, Aron Oxetane OXT-221 (bis[1-ethyl(3-oxetanyl))methyl ether) manufactured by Nippon Biosynthetics Co., Ltd., 45.0 parts by mass and Aron Oxetane OXT-211 (3 manufactured by Nippon Biosynthetics Co., Ltd.) 15.0 parts by mass of ethyl-3-(phenoxymethyl)oxetane) and CPI-100P as a photocationic polymerization initiator (C) (diphenyl-4 manufactured by SAN-APRO Co., Ltd.) A (50% by mass solution of propionate of (phenylthio)phenylphosphonium hexafluorophosphate) was added in an amount of 4 parts by mass to prepare a cationically polymerizable adhesive (6). The chlorine content contained in the total amount of the obtained cationically polymerizable adhesive (6) was determined to be 212 ppm in accordance with the method described later.

[Embodiment 7]

In a closed planetary mixer, 20.0 parts by mass of a glycidyl propyl ether-containing compound (B-1) and 20.0 parts by mass of a glycidyl propyl ether group-containing compound (B'-3) by mixing and stirring, Aron Oxetane 35.0 parts by mass of OXT-221 (bis[1-ethyl(3-oxetanyl))methyl ether) manufactured by Japan East Asia Synthetic Co., Ltd. and Aron Oxetane OXT-211 (made by Japan East Asia Synthetic Co., Ltd.) 25.0 parts by mass of ethyl-3-(phenoxymethyl)oxetane) and CPI-100P as a photocationic polymerization initiator (C) (diphenyl-4 manufactured by SAN-APRO Co., Ltd.) A (50% by mass solution of propionate of (phenylthio)phenylphosphonium hexafluorophosphate) was added in an amount of 4 parts by mass to prepare a cationically polymerizable adhesive (7). The chlorine content contained in the total amount of the obtained cationically polymerizable adhesive (7) was determined by the method described later to be 214 ppm.

[Embodiment 8]

In a closed planetary mixer, 20.0 parts by mass of a glycidyl propyl ether-containing compound (B-1) and 20.0 parts by mass of a glycidyl propyl ether group-containing compound (B'-3) by mixing and stirring, Aron Oxetane 35.0 parts by mass of OXT-221 (bis[1-ethyl(3-oxetanyl))methyl ether) manufactured by Japan East Asia Synthetic Co., Ltd. and Aron Oxetane OXT-212 (3 manufactured by Japan East Asia Synthetic Co., Ltd.) 25.0 parts by mass of ethyl-3-(2-ethylhexyloxymethyl)oxetane) and CPI-100P as a photocationic polymerization initiator (C) (two manufactured by SAN-APRO Co., Ltd.) A cationically polymerizable adhesive (8) was prepared by dissolving 4 parts by mass of a phenyl-4-(phenylthio)phenylphosphonium hexafluorophosphate propionate 50% by mass solution. The chlorine content contained in the total amount of the obtained cationically polymerizable adhesive (8) was 208 ppm as determined by the method described later.

[Embodiment 9]

In a closed planetary mixer, 20.0 parts by mass of a glycidyl propyl ether-containing compound (B-1) and 20.0 parts by mass of a glycidyl propyl ether group-containing compound (B'-3) by mixing and stirring, Aron Oxetane 35.0 parts by mass of OXT-221 (bis[1-ethyl(3-oxetanyl))methyl ether) manufactured by Japan East Asia Synthetic Co., Ltd. and Aron Oxetane OXT-213 (3 manufactured by Nippon Biosynthetics Co., Ltd.) 25.0 parts by mass of ethyl-3-(cyclohexyloxy)methyloxetane) and CPI-100P as a photocationic polymerization initiator (C) (diphenyl group manufactured by SAN-APRO Co., Ltd.) A solution of a cationically polymerizable adhesive (9) was prepared by dissolving 4 parts by mass of a 4-propionate (50% by mass solution of -4-(phenylthio)phenylphosphonium hexafluorophosphate). The chlorine content contained in the total amount of the obtained cationically polymerizable adhesive (9) was 215 ppm as determined by the method described later.

[Embodiment 10]

In a closed planetary mixer, 20.0 parts by mass of a glycidyl propyl ether-containing compound (B-1) and 20.0 parts by mass of a glycidyl propyl ether group-containing compound (B'-3) by mixing and stirring, Aron Oxetane 25.0 parts by mass of OXT-221 (bis[1-ethyl(3-oxetanyl))methyl ether) manufactured by Japan East Asia Synthetic Co., Ltd. and Aron Oxetane OXT-211 (made by Japan East Asia Synthetic Co., Ltd.) -Ethyl-3-(phenoxymethyl)oxetane) 30.0 parts by mass, CELLOXIDE 2021P as an alicyclic epoxy compound (E) (3,4-epoxy manufactured by DAICEL Chemical Industry Co., Ltd.) 5.0 parts by mass of a cyclohexenylmethyl-3',4'-epoxycyclohexanecarboxylate), KBE-403 as an epoxy group-containing decane compound (F) (manufactured by Shin-Etsu Chemical Co., Ltd.) 0.5 parts by mass of 3-glycidylpropyltriethoxydecane) and CPI-100P as a photocationic polymerization initiator (C) (diphenyl-4-(benzene) manufactured by SAN-APRO Co., Ltd. The cation-polymerizable adhesive (10) was prepared by dissolving 4 parts by mass of a solution of a propionate 50% by mass of thio)phenyl hexafluorophosphate. The chlorine content contained in the total amount of the obtained cationically polymerizable adhesive (10) was 216 ppm as determined by the method described later.

[Example 11]

In a closed planetary mixer, 20.0 parts by mass of a glycidyl propyl ether-containing compound (B-1) and 20.0 parts by mass of a glycidyl propyl ether group-containing compound (B'-3) by mixing and stirring, Aron Oxetane 35.0 parts by mass of OXT-221 (bis[1-ethyl(3-oxetanyl))methyl ether) manufactured by Japan East Asia Synthetic Co., Ltd. and Aron Oxetane OXT-211 (made by Japan East Asia Synthetic Co., Ltd.) 25.0 parts by mass of ethyl-3-(phenoxymethyl)oxetane), CELLOXIDE 2021P as an alicyclic epoxy compound (E) (3,4-epoxy manufactured by DAICEL Chemical Industry Co., Ltd.) 5.0 parts by mass of a cyclohexenylmethyl-3',4'-epoxycyclohexanecarboxylate), KBE-403 as an epoxy group-containing decane compound (F) (manufactured by Shin-Etsu Chemical Co., Ltd.) 0.5 parts by mass of 3-glycidylpropyltriethoxydecane) and CPI-100P as a photocationic polymerization initiator (C) (diphenyl-4-(benzene) manufactured by SAN-APRO Co., Ltd. The cation-polymerizable adhesive (11) was prepared by dissolving 4 parts by mass of a solution of a propionate 50% by mass of thio)phenylphosphonium hexafluorophosphate. The chlorine content contained in the total amount of the obtained cationically polymerizable adhesive (11) was 216 ppm as determined by the method described later.

[Comparative Example 1]

In a closed planetary mixer, 40.0 parts by mass of a epoxidized propyl ether group-containing compound (B'-3) and Aron Oxetane OXT-221 (a double [1-ethyl group manufactured by Nippon Biosynthetics Co., Ltd.) were mixed and stirred. (3-oxetanyl)]methyl ether) 35.0 parts by mass and Aron Oxetane OXT-101 (3-hydroxymethyl-3-ethyloxetane manufactured by Japan East Asia Synthetic Co., Ltd.) 25.0 mass And CPI-100P as a photocationic polymerization initiator (C) (propionate of diphenyl-4-(phenylthio)phenylphosphonium hexafluorophosphate manufactured by SAN-APRO Co., Ltd. 50% by mass The solution) 4 parts by mass to prepare a cationically polymerizable adhesive (1'). The chlorine content contained in the total amount of the obtained cationically polymerizable adhesive (1') was 194 ppm as determined by the method described later.

[Comparative Example 2]

In a closed planetary mixer, by mixing and stirring 40.0 parts by mass of a glycidyl propyl ether-containing compound (B'-4), Aron Oxetane OXT-221 (double [1-ethyl] manufactured by Nippon Biosynthetics Co., Ltd. (3-oxetanyl)]methyl ether) 35.0 parts by mass and Aron Oxetane OXT-101 (3-hydroxymethyl-3-ethyloxetane manufactured by Japan East Asia Synthetic Co., Ltd.) 25.0 mass And CPI-100P as a photocationic polymerization initiator (C) (propionate of diphenyl-4-(phenylthio)phenylphosphonium hexafluorophosphate manufactured by SAN-APRO Co., Ltd. 50% by mass The solution) 4 parts by mass to prepare a cationically polymerizable adhesive (2'). The chlorine content contained in the total amount of the obtained cationically polymerizable adhesive (2') was 383 ppm as determined by the method described later.

[Comparative Example 3]

In a sealed planetary mixer, 20.0 parts by mass of a glycidyl propyl ether-containing compound (B'-3) and 20.0 parts by mass of a glycidyl propyl ether group-containing compound (B-1) by mixing and stirring, Aron Oxetane OXT-191 (oxetane citrate manufactured by Nippon Biosynthetics Co., Ltd.) 35.0 parts by mass and Aron Oxetane OXT-101 (3-hydroxymethyl-3-ethyloxycyclohexane manufactured by Nippon Biosynthetics Co., Ltd.) Butane) 25.0 parts by mass, and CPI-100P as a photocationic polymerization initiator (C) (diphenyl-4-(phenylthio)phenylphosphonium hexafluorophosphate manufactured by SAN-APRO Co., Ltd.) The acid polymerizable adhesive (3') was prepared by dissolving 4 parts by mass of the acid ester 50% by mass solution. The chlorine content contained in the total amount of the obtained cationically polymerizable adhesive (3') was 211 ppm as determined by the method described later.

[Comparative Example 4]

In a closed planetary mixer, 20.0 parts by mass of a glycidyl propyl ether-containing compound (B'-3) and 20.0 parts by mass of a glycidyl propyl ether group-containing compound (B-2) by mixing and stirring, Aron Oxetane OXT-191 (oxetane citrate manufactured by Nippon Biosynthetics Co., Ltd.) 35.0 parts by mass and Aron Oxetane OXT-101 (3-hydroxymethyl-3-ethyloxycyclohexane manufactured by Nippon Biosynthetics Co., Ltd.) Butane) 25.0 parts by mass, and CPI-100P as a photocationic polymerization initiator (C) (diphenyl-4-(phenylthio)phenylphosphonium hexafluorophosphate manufactured by SAN-APRO Co., Ltd.) The 50% by mass of the acid ester solution) was used in an amount of 4 parts by mass to prepare a cationically polymerizable adhesive (4'). The chlorine content contained in the total amount of the obtained cationically polymerizable adhesive (4') was 213 ppm as determined by the method described later.

[Comparative Example 5]

In a closed planetary mixer, 20.0 parts by mass of a glycidyl ether-containing compound (B-1) and 20.0 parts by mass of a glycidyl propyl ether group-containing compound (B'-5) by mixing and stirring, Aron Oxetane 35.0 parts by mass of OXT-221 (bis[1-ethyl(3-oxetanyl))methyl ether) manufactured by Japan East Asia Synthetic Co., Ltd. and Aron Oxetane OXT-101 (made by Japan East Asia Synthetic Co., Ltd.) 25.0 parts by mass of -hydroxymethyl-3-ethyloxetane) and CPI-100P as a photocationic polymerization initiator (C) (diphenyl-4-(benzene) manufactured by SAN-APRO Co., Ltd. A cationically polymerizable adhesive (5') was prepared by dissolving 4 parts by mass of a solution of a propionate 50% by mass of thio)phenylphosphonium hexafluorophosphate. The chlorine content contained in the total amount of the obtained cationically polymerizable adhesive (5') was 2019 ppm as determined by the method described later.

[Comparative Example 6]

In a closed planetary mixer, 40.0 parts by mass of a epoxidized propyl ether group-containing compound (B'-6) was mixed and stirred, and Aron Oxetane OXT-221 (a double [1-ethyl group manufactured by Japan East Asia Synthetic Co., Ltd.) (3-oxetanyl)]methyl ether) 35.0 parts by mass and Aron Oxetane OXT-101 (3-hydroxymethyl-3-ethyloxetane manufactured by Japan East Asia Synthetic Co., Ltd.) 25.0 mass And CPI-100P as a photocationic polymerization initiator (C) (propionate of diphenyl-4-(phenylthio)phenylphosphonium hexafluorophosphate manufactured by SAN-APRO Co., Ltd. 50% by mass The solution) was used in an amount of 4 parts by mass to prepare a cationically polymerizable adhesive (6'). The chlorine content contained in the total amount of the obtained cationically polymerizable adhesive (6') obtained by the method described later was 13,462 ppm.

[Method for determination of total chlorine content]

The chlorine content contained in the cationically polymerizable adhesive of the present invention is measured in accordance with JIS K 1200-3-2:00. Specifically, the amount of chlorine in the present invention is an adhesive for 0.05% or more of sodium chloride, and the value obtained by the Volhard improvement method is used as the chlorine content of the adhesive; for the adhesive of less than 0.05%, The value obtained by ion chromatography analysis was used as the chlorine content of the adhesive.

[Method of making polarizer]

A polyvinyl alcohol aqueous solution (nonvolatile matter) obtained by dissolving KURARAY POVAL PVA-117H (polyvinyl alcohol manufactured by KURARAY, polymerization degree 1700, completely saponified product, powder form) in water by using a bar coater 8 mass %) was apply|coated on the release film, and it dried by the environment of 80 degreeC for 5 minutes, and after removal of this release film, the polyvinyl-

Next, the obtained polyvinyl alcohol film was fixed in a stretching machine, and the film was stretched in a temperature of 40 ° C in a uniaxial direction to a size of three times.

After removing the water adhering to the surface of the stretched film obtained above, the stretched film was immersed in an aqueous solution adjusted to 30 ° C containing 0.02 parts by mass of iodine, 2 parts by mass of potassium iodide, and 100 parts by mass of water.

Next, the stretched film was immersed in an aqueous solution adjusted to 56.5 ° C containing 12 parts by mass of potassium iodide, 5 parts by mass of boric acid, and 100 parts by mass of water.

After the impregnated stretched film was washed in pure water adjusted to 8 ° C, it was dried at 65 ° C to obtain iodine adsorption and alignment on the surface of the stretched film formed of polyvinyl alcohol. Mirror (polarizing film).

[Manufacturing method of polarizing plate]

The cationic polymerization obtained in the examples and the comparative examples was applied to the one-side surface of two sheets of triacetyl cellulose film (thickness: 80 μm, length: 297 mm, width: 210 mm) which was subjected to corona treatment so as to have a thickness of 2 μm using a coater. As the adhesive, a belt-type ultraviolet irradiation device CSOT-40 (a high-pressure mercury lamp manufactured by Nippon Battery Co., Ltd., strength: 120 W/cm) was used, and ultraviolet rays of 30 to 100 mJ/cm ^{2 were} irradiated onto the coated surface.

Next, the two sheets of the triacetyl cellulose film were bonded to both surfaces of a polarizer (thickness: 42 μm, length: 297 mm, width: 210 mm) obtained by the method, and pressed with a rubber roller, and then, A polarizing plate was prepared by heating in a dryer at 60 ° C for 1 minute.

[Evaluation method of normal state strength]

The polarizing plate obtained by the method was placed in a dryer set at 85 ° C for 1500 hours, and then a tensile tester (manufactured by Ikuta Seisakusho Co., Ltd., tensile speed = 50 mm/min, T-peeling) was used. The peel strength at the interface between the triacetyl cellulose and the polyvinyl alcohol constituting each of the polarizing plates was measured. The peel strength of 10 N/25 mm or more or the rupture (MB) of the triacetyl cellulose film was evaluated as "good"; those below 10 N/25 mm were evaluated as "poor".

[Evaluation of changes in penetration rate or fading of polarizers]

The degree of fading and discoloration of the polarizer caused by the influence of the cationically polymerizable adhesive is at a temperature of 65 ° C and a humidity of 90%, and the polarizing plate produced by the method is placed for 1500 hours before, according to the polarized light. The rate of change in the penetration rate of the plate was evaluated.

The transmittance of the polarizing plate was measured using a visible light spectrophotometer (JASCO V-570, manufactured by JASCO Corporation, measuring wavelength: 200 to 900 nm, scanning speed: 400 nm/min). With respect to the transmittance (%) of the polarizing plate before the placement, the transmittance (%) of the polarizing plate after the placement is ±5% or more, and the change is evaluated as "╳"; When the transmittance of the polarizing plate is less than ±5%, it is evaluated as "○".

Claims (14)

A cationically polymerizable adhesive comprising an oxetane compound (A) having two or more oxetanyl groups having a molecular weight of from 100 to 800, an aromatic epoxidized propyl ether (B), and a cationic polymerization The initiator (C) and the binder containing the epoxy group-containing decane compound (F) are characterized in that the amount of chlorine remaining in the total amount of the binder is 1,500 ppm or less. The cationically polymerizable adhesive according to claim 1, wherein the oxetane compound (A) is bis[1-ethyl(3-oxetanyl)methyl ether. The cationically polymerizable adhesive according to claim 1, wherein the aromatic epoxy propyl ether (B) is a group consisting of bisphenol A diglycidyl ether and bisphenol F diglycidyl ether. One or more selected from the group. The cationically polymerizable adhesive according to claim 1, which further comprises an oxetane compound (D) having one oxetanyl group, and the oxetane compound (A) has The equivalent ratio of the oxetane group to the oxetane group of the oxetane compound (D) [(A) has an oxetanyl group of the oxetanyl group/(D) Butane] is 0.1 to 35.0. The cationically polymerizable adhesive agent according to claim 4, wherein the oxetane compound (D) has a molecular weight of from 100 to 500. The cationically polymerizable adhesive according to claim 4, wherein the oxetane compound (D) is 3-hydroxymethyl-3-ethyloxetane, 3-ethyl-3- (phenoxymethyl)oxetane, 3-ethyl-3-(2-ethylhexyloxymethyl)oxetane and 3-ethyl-3-(cyclohexyloxy) One or more selected from the group consisting of methyloxetane. A cationically polymerizable adhesive according to claim 4, which contains bis[1-ethyl(3-oxetanyl)methyl ether as the oxetane compound (A) The content of the cation-polymerizable adhesive is from 20 to 70% by mass, and the oxetane compound (D) is contained by 3-hydroxymethyl-3-ethyloxetane. 3-ethyl-3-(phenoxymethyl)oxetane, 3-ethyl-3-(2-ethylhexyloxymethyl)oxetane and 3-ethyl-3 One or more selected from the group consisting of -(cyclohexyloxy)methyloxetane are 20 to 70% by mass. A cationically polymerizable adhesive agent according to claim 1, which further has an alicyclic epoxy compound (E). The cationically polymerizable adhesive according to the eighth aspect of the invention, wherein the alicyclic epoxy compound (E) has a structure represented by the following formula (7); (a in the formula (7) represents 0 or 1). A cationically polymerizable adhesive according to claim 8 wherein the alicyclic epoxy compound (E) is a 3,4-epoxycyclohexenylmethyl-3',4'-epoxy ring. Hexane formate. The cationically polymerizable adhesive according to the first aspect of the invention, wherein the epoxy group-containing decane compound (F) is contained in an amount of from 0.1 to 1.5% by mass based on the total amount of the cationically polymerizable adhesive. a cationically polymerizable adhesive as claimed in claim 1 wherein The epoxy group-containing decane compound (F) is composed of 3-glycidoxypropyltriethoxydecane, 3-glycidoxypropyltrimethoxydecane, 3-glycidoxypropylmethyldiethyl Oxydecane, 3-glycidoxypropylmethyldimethoxydecane, 2-(3,4-epoxycyclohexyl)ethyltriethoxydecane, and 2-(3,4-ring One or more selected from the group consisting of oxycyclohexyl)ethyltrimethoxydecane. The cationically polymerizable adhesive according to any one of claims 1 to 12, which is used for the adhesion between a polarizer and a protective film constituting a polarizing plate. A polarizing plate which is a polarizing plate formed by a cationically polymerizable adhesive followed by a protective film formed of triacetyl cellulose or a protective film formed of a cyclic olefin, and a polarizer formed of polyvinyl alcohol. The cationically polymerizable adhesive is a cationically polymerizable adhesive of claim 13 of the patent application.