KR20140121093A

KR20140121093A - Pressure-sensitive adhesive composition for optical use

Info

Publication number: KR20140121093A
Application number: KR20130037305A
Authority: KR
Inventors: 최한영; 권혜림
Original assignee: 동우 화인켐 주식회사
Priority date: 2013-04-05
Filing date: 2013-04-05
Publication date: 2014-10-15

Abstract

The present invention relates to a pressure-sensitive adhesive composition for optical applications, and more particularly to a pressure-sensitive pressure-sensitive adhesive composition for optical pressure-sensitive adhesive compositions which comprises a monofunctional urethane acrylate oligomer having an ionic functional group at its terminal; Monofunctional acrylate monomers; And a free radical initiator, it not only has excellent adhesion to plastic materials but also inorganic materials, and has excellent durability against heat and moisture and heat, and does not contain any additional solvent. Therefore, To a pressure-sensitive adhesive composition.

Description

PRESSURE-SENSITIVE ADHESIVE COMPOSITION FOR OPTICAL USE

The present invention relates to a pressure-sensitive adhesive composition for optical applications having excellent adhesion to an inorganic material as well as a plastic material, and excellent durability such as heat resistance and anti-wet heat.

Recently, in the rapidly developing display industry, optically transparent pressure-sensitive pressure-sensitive adhesives are frequently used to mount a touch panel or a touch screen or to obtain high brightness and high permeability.

A touch panel or a touch screen is a device for finding a position coordinate by recognizing a change in a potential difference generated by using a predetermined input means such as a pen or a finger. Specifically, when a certain point on the upper substrate is pressed, an upper electrode formed of a transparent conductive film and a lower electrode formed of a transparent conductive film are brought into contact with each other at a lower portion of the upper substrate, and a potential difference is generated. .

In recent years, the touch panel or the touch screen has been used as a device for inputting information in combination with a display device.

The pressure-sensitive adhesive used for attaching the transparent conductive film of the touch screen or the touch panel suppresses the occurrence of curl or bubbles even when exposed to harsh conditions such as high temperature and high humidity conditions, Durability is required.

In general, an acrylic or urethane acrylic pressure-sensitive adhesive is used to ensure the visibility of the display. Such a pressure-sensitive adhesive requires a separate thickening step (thickness: 50 to 1000 mm), and there is a problem that durability such as physical properties and heat resistance is deteriorated as an adhesive layer such as an adhesive force under severe conditions.

In this regard, Korean Patent Laid-Open Publication No. 2012-72163 discloses a pressure-sensitive adhesive composition containing a urethane (meth) acrylate copolymer having a hydroxyl group and a vinyl group at a terminal thereof to improve reworkability, To solve the cost increase problem. However, the above method has a problem that the adhesion failure under severe conditions is so low that the peeling failure can not be sufficiently suppressed.

The present invention is intended to provide a pressure-sensitive adhesive composition for optical applications having excellent adhesion to an inorganic material as well as a plastic material, heat resistance and durability such as anti-wet heat.

In order to accomplish the above object, the present invention provides a method for producing a polyimide film, which comprises: a monofunctional urethane acrylate oligomer having an ionic functional group at a terminal; Monofunctional acrylate monomers; And a free radical initiator.

The monofunctional urethane acrylate oligomer may be polymerized by containing a polyol, a diisocyanate compound, an acrylate monomer having a hydroxyl group, and an ionic compound having a hydroxyl group or a thiol group.

Wherein the ionic compound comprises a cation having a hydroxyl group or a thiol group; A fluorine-containing inorganic salt or an anion of a fluorine-containing organic salt.

Preferably, the ionic compound is selected from the group consisting of 1-butyl-4- (3-hydroxymethyl) pyridinium tetrafluoroborate, 1-butyl- 4- (3- hydroxymethyl) pyridinium hexafluorophosphate, 1 Butyl-4- (3-hydroxypropyl) pyridinium tetrafluoroborate, 1-butyl-4- (3- hydroxypropyl) pyridinium trifluoromethanesulfonate, Butyl-4- (3-hydroxypropyl) pyridinium bis (pentafluoroethanesulfonyl) imide, 1-butyl-4- 1- (3-mercaptopropyl) pyridinium tetrafluoroborate, 1- (3-hydroxypropyl) pyridinium hexafluorophosphate, 1- 1- (3-mercaptopropyl) pyridinium trifluoromethanesulfonate, 1- (3-mercaptopropyl) pyridinium hexafluorophosphate, 1- Bis (trifluoromethanesulfonyl) imide, 1- (3-mercaptopropyl) pyridinium bis (pentafluoroethanesulfonyl) imide, 1-ethyl-3-hydroxymethylindole hexafluorophosphate, Ethyl-5-hydroxyindole hexafluorophosphate, 1-ethyl-6-hydroxyindole hexafluorophosphate, 1-methyl-3- (2- hydroxyethyl) imidazolium hexafluorophosphate, 1 Methyl-3- (2-hydroxyethyl) imidazolium trifluoromethanesulfonate, 1-methyl-3- (2-hydroxyethyl) imidazolium trifluoromethanesulfonate, Imidazolium bis (trifluoromethanesulfonyl) imide, 1-methyl-3- (2-methyl-2-hydroxyethyl) imidazolium bis (Trifluoromethanesulfonyl) imide, 1-methyl-3- (2,2-dimethyl-2-hydroxyethyl) imidazolium bis (trifluoromethanesulfonyl) - (2-hydroxyethyl) imidazolium bis ( Butyl-3- (2-hydroxyethyl) imidazolium tetrafluoroborate, 1-butyl-3- (2-hydroxyethyl) imidazolium hexafluoro Phosphate, 1-butyl-3- (2-hydroxyethyl) imidazolium trifluoromethanesulfonate, 1-butyl-3- (2- hydroxyethyl) imidazolium trifluoromethanesulfonate, 1- Imidazolium bis (trifluoromethanesulfonyl) imide, 1-octyl-3- (2,2-dimethyl-2-hydroxyethyl ) Imidazolium bromide, 1-dodecyl-3- (2-hydroxyethyl) imidazolium chloride, 1-tetradecyl-3- (2,2- Imidazolium hexafluorophosphate, 1-hexyl-2-methyl-3- (2-hydroxyethyl) imidazolium hexafluorophosphate, 1- Butyl-3- (2-thiolethyl) imidazolium bis (trifluoromethanesulphonyl) 1- (12-mercaptododecyl) -3-methylimidazolium hexafluorophosphate, 1,3-dimethyl-2-mercapto-1,4,5,6-tetrahydropyrimidine 1-hydroxymethylpyrazolium tetrafluoroborate, and 1-hydroxymethyl-2-methylpyrazolinium hexafluorophosphate, which are selected from the group consisting of bis (trifluoromethanesulfonyl) imide, Or more.

40 to 80% by weight of a monofunctional urethane acrylate oligomer having an ionic functional group at the terminal; 5 to 55% by weight monofunctional acrylate monomer; And from 0.1 to 5% by weight of a free radical initiator.

The pressure-sensitive adhesive composition of the present invention not only has excellent adhesion to inorganic materials as well as plastic materials, but also has excellent durability such as heat resistance and anti-wet heat.

Further, since the pressure-sensitive adhesive composition of the present invention does not contain a separate solvent, it is possible to produce a thick-film type pressure-sensitive adhesive film.

Hereinafter, the present invention will be described in detail.

The pressure-sensitive adhesive composition for optical use of the present invention comprises a monofunctional urethane acrylate oligomer having an ionic functional group at a terminal; Monofunctional acrylate monomers; And a free radical initiator. Here, the oligomer generally means a low molecular weight polymer compound having a weight average molecular weight (Mw) of 1,000 to 40,000, preferably 1,000 to 35,000.

The monofunctional urethane acrylate oligomer having an ionic functional group at the end serves to maintain viscoelasticity and storage elasticity by imparting physical properties and flexibility of a pressure-sensitive adhesive.

If the urethane acrylate oligomer is polyfunctional, the surface tackiness is poor and the cohesive strength is too high, so that the appearance of the adhesive property is not easy. In the case of having an alkoxy group at the terminal instead of the ionic functional group, the adhesive force is not sufficiently high, so that peeling failure may occur under heat-resistant conditions. In the case of having a hydroxy group, the adhesive strength is increased, I will not.

The monofunctional urethane acrylate oligomer of the present invention is preferably polymerized by containing a polyol, a diisocyanate compound, an acrylate monomer having a hydroxy group, and an ionic compound having a hydroxyl group or a thiol group.

Specifically, the monofunctional urethane acrylate oligomer having an ionic functional group at the terminal thereof comprises a main chain portion derived from a polyol; A urethane bonding group formed by the reaction of a diisocyanate and a polyol; A reactive group of an acryloyl group at one end from an acrylate monomer having a hydroxy group and an ionic compound having a hydroxy group or a thiol group. And the other end has an ionic functional group.

The main chain may be derived from a polyol having at least one molecular structure selected from the group consisting of polyethers, polyesters, polyolefins, polyacrylates, and polycarbonates. From the viewpoint of easiness of controlling the price and viscosity, it is preferable to be derived from a polyol having a polyester, polyether or a mixed structure thereof.

The urethane linking group can be produced by a known method of polymerizing a polyol and a diisocyanate compound.

As the polyol, for example, an oligomer having an ether backbone can be prepared by using a cyclic ether monomer such as oxirane such as ethylene oxide, propylene oxide or tetrahydrofuran. Further, an oligomer having an ester main chain can be prepared by using a cyclic ester such as? -Caprolactone or pivalolactone.

The diisocyanate compound may be 1,4-butylene diisocyanate, 1,6-hexamethylene diisocyanate, cyclopentylene-1,3-diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, isophorone diisocyanate , Cyclohexene-1,4-diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4'-methylene bis (phenyl isocyanate), 2,2- , 4'-diisocyanate, p-phenylene diisocyanate, m-phenylenediisocyanate, xylene diisocyanate, 1,4-naphthylene diisocyanate, 1,5-naphthylene diisocyanate 4,4'-diphenyl diisocyanate , At least one aliphatic diisocyanate compound selected from the group consisting of azobenzene-4,4'-diisocyanate, m- or p-tetramethylxylene diisocyanate and 1-chlorobenzene-2,4- Is recommended.

Usually, the polyol and the diisocyanate compound are reacted at an equivalent ratio, and it is preferable to use an excessive amount of the diisocyanate compound to form an isocyanate group at the terminal. More preferably, it is used in an amount of 1.01 to 1.1 equivalents based on 1 equivalent of the polyol.

At one end, a urethane acrylic oligomer is prepared by reacting 2-hydroxyethyl (meth) acrylate with an acrylate monomer having a hydroxyl group to form a reactive group of an acryloyl group. At this time, it is preferable to control the content of the acrylate monomer having a hydroxyl group so that it can react with the half of the residual amount of the diisocyanate compound remaining after the reaction with the polyol.

Also, the amount corresponding to the other half of the residual amount of the diisocyanate compound is subjected to the reaction using an ionic compound having a hydroxyl group or a thiol group.

More preferably, the ionic compound having 30 to 70 functional groups, a hydroxyl group or a thiol group in the acrylate monomer having a hydroxyl group is preferably used in a number of 70 to 30 functional groups, relative to 100 of the remaining isocyanate functional groups.

The ionic compound having a hydroxy group or thiol group may be an ionic compound having various skeletons, and any ionic compound composed of a cation containing a hydroxyl group or a thiol group and an anion may be used regardless of the kind.

The cation containing a hydroxyl group or a thiol group may be a pyridinium cation, a piperidinium cation, a pyrrolidinium cation, a cation having a pyrrole skeleton, an imidazolium cation, a tetrahydropyrimidinium cation, a dihydropyrimidinium cation, a pyrazolium cation A cation and a pyrazolinium cation can be used.

Specifically, a cation such as a 1-ethyl-4- (hydroxymethyl) pyridinium cation, a 1-ethyl-4- (3-hydroxypropyl) pyridinium cation, Butyl-4- (hydroxymethyl) pyridinium cation, 1-ethyl-2- (3-hydroxypropyl) pyridinium cation, 1- (3-hydroxypropyl) pyridinium cation, a 1-butyl-4-hydroxypyridinium cation, a 1-butyl-2- (hydroxymethyl) pyridinium cation, 1-hexyl-4- (hydroxymethyl) pyridinium cation, 1-hexyl-4-hydroxypyridinium cation, 1-hexyl- Butyl-4-methyl-2-hydroxypyridinium cation, 1-hexyl-2- (3-hydroxypropyl) pyridinium cation, Methyl-2-hydroxymethylpyridinium cation, 1- (2-hydroxy Ethyl (2-hydroxyethyl) piperidinium cation, 1,1-ethylmethyl-2-hydroxymethylpyridinium cation, (2-hydroxyethyl) pyrrolidinium cation, 1,1-ethyl-3-hydroxypiperidinium cation, 1,1- Diethyl-3-hydroxypyrrolidinium cation, 1,1-ethylmethyl-2- (2-hydroxyethyl) pyrrolidinium cation, 1-ethyl- Ethyl-6-hydroxyindole cation, 1- (3-mercaptopropyl) pyridinium cation, 1-methyl-3- 1-methyl-3- (2-methyl-2-hydroxyethyl) imidazolium cation, Methyl-3- (2,2-dimethyl-2-hydroxyethyl) imidazolium cation, 1-ethyl-3- (2-hydroxyethyl) imidazolium cation, 1-butyl-3- (2-hydroxyethyl) imidazolium cation, 1-butyl- 1-hexyl-3- (2-methyl-2-hydroxyethyl) imidazolium cation, 1-octyl 3- (2,2- Imidazolium cation, 1-tetradecyl-3- (2,2-dimethyl-3-hydroxypropyl) imidazolium cation, 1,2-dimethyl- (2-hydroxyethyl) imidazolium cation, 1-ethyl-2,3-methyl (2-hydroxyethyl) imidazolium cation, 1-butyl- (2-hydroxyethyl) imidazolium cation, 1- (12-mercaptododecyl) -3-methylimidazolium cation, 1-butyl- -Thiethylethyl) imidazolium cation, 1,3-dimethyl-2-mercapto-1,4,5,6-tetrahydropyrimidinium cation, 1-hydroxymethylpyrazolinium cation and 1- De-hydroxy-2-methylpyrazole and the like Jolly cation.

The anion is not particularly limited to those generally used in the art, but an anion of a fluorine-containing inorganic salt or a fluorine-containing organic salt is preferable in view of compatibility with an acrylic monomer. Anion specifically, ^{Cl -, Br -, I -} , AlCl 4 -, Al 2 Cl 7 -, BF 4 -, PF 6 -, SbF 6 -, NO 3 -, ClO 4 -, CH 3 COO -, CF 3 ^{_{^{COO -, CH 3 SO 3 -}}} , CF 3 SO 3 -, (CF 3 SO 2) 2 N-, (C 2 F 5 SO 2) 2 N -, C 3 F 7 COO - , and (CF ₃ SO ₂₎ (CF ₃ CO) N ^- can be used.

Preferably, the ionic compound having a hydroxyl group or thiol group is selected from the group consisting of 1-butyl-4- (3-hydroxymethyl) pyridinium tetrafluoroborate, 1-butyl- 4- (3-hydroxymethyl) pyridinium hexafluoro Butyl-4- (3-hydroxypropyl) pyridinium trifluoromethanesulfonate, 1-butyl-4- (3-hydroxypropyl) pyridinium tetrafluoroborate, (Pentafluoroethanesulfonyl) imide, 1-butyl-4- (3-hydroxypropyl) pyridinium bis (pentafluoroethanesulfonyl) 1-hexyl-4-hydroxypyridinium tetrafluoroborate, 1- (3-mercaptopropyl) pyridinium tetrafluoroborate, 1- (3-hydroxypropyl) pyridinium hexafluorophosphate, 1- (3-mercaptopropyl) pyridinium hexafluorophosphate, 1- (3-mercaptopropyl) pyridinium trifluoromethanesulfonate, 1 1- (3-mercaptopropyl) pyridinium bis (pentafluoroethanesulfonyl) imide, 1- (3-mercaptopropyl) pyridinium bis (trifluoromethanesulfonyl) 1-ethyl-5-hydroxyindole hexafluorophosphate, 1-ethyl-6-hydroxyindole hexafluorophosphate, 1-methyl-3- (2- ) Imidazolium hexafluorophosphate, 1-methyl-3- (2-hydroxyethyl) imidazolium trifluoromethanesulfonate, 1-methyl-3- (2- hydroxyethyl) imidazolium trifluoro Methyl-3- (2-methyl-3-hydroxypropyl) imidazolium bis (trifluoromethanesulfonyl) imide, Imidazolium bis (trifluoromethanesulfonyl) imide, 1-methyl-3- (2,2-dimethyl-2-hydroxyethyl) imidazolium bis (2-hydroxyphenyl) imide, 1-butyl-3- (2-hydroxyethyl) imidazolium tetrafluoroborate, 1-butyl-3- (2-hydroxyphenyl) imidazolium bis (trifluoromethanesulfonyl) imide, Ethyl) imidazolium hexafluorophosphate, 1-butyl-3- (2-hydroxyethyl) imidazolium trifluoromethanesulfonate, 1-butyl-3- (2- hydroxyethyl) imidazolium tri (2,2-dimethyl-3-hydroxypropyl) imidazolium bis (trifluoromethanesulfonyl) imide, 1-octyl-3- (2-hydroxyethyl) imidazolium chloride, 1-tetradecyl-3- (2,2-dimethyl-3-hydroxyphenyl) imidazolium bromide, Hydroxypropyl) imidazolium chloride, 1,2-dimethyl-3- (2-hydroxyethyl) imidazolium hexafluorophosphate, 1-hexyl- Thiomethyl hexafluorophosphate, 1-butyl-3- (2-thiol ethyl) imidazole Bis (trifluoromethanesulfonyl) imide, 1- (12-mercaptododecyl) -3-methylimidazolium hexafluorophosphate, 1,3-dimethyl-2-mercapto-1,4,5 , 6-tetrahydropyrimidinium bis (trifluoromethanesulfonyl) imide, 1-hydroxymethyl pyrazolium tetrafluoroborate, and 1-hydroxymethyl-2-methylpyrazolinium hexafluorophosphate And the like.

The monofunctional urethane acrylate oligomer having an ionic functional group at the terminal thereof preferably has a glass transition temperature (Tg) of -60 to 50 캜, preferably -60 to 20 캜.

Such a monofunctional urethane acrylate oligomer may contain from 40 to 80% by weight, preferably from 50 to 70% by weight. If the content is less than 40% by weight, the viscosity of the pressure-sensitive adhesive composition may be low, and the coating may be difficult. When the content is more than 80% by weight, it may be difficult to control the balance between the viscosity and optical properties of the pressure-sensitive adhesive composition.

The monofunctional acrylate monomer serves to impart durability to the film containing the pressure-sensitive adhesive composition, maintain the viscoelasticity, and adjust the viscosity to improve the coating property of the composition.

(Meth) acrylate, ethyl acrylate, butyl acrylate, isobutyl acrylate, allyl methacrylate, 2-ethoxyethyl (meth) acrylate, isodecyl (Meth) acrylate, hydroxypropyl (meth) acrylate, hydroxypropyl (meth) acrylate, 2-ethylhexyl acrylate, Acrylate, stearyl (meth) acrylate, tetrapurfuryl (meth) acrylate, phenoxyethyl (meth) acrylate, isobutyl (meth) acrylate, Octadecyl methacrylate, isobonyl (meth) acrylate, tetrahydrofuryl acrylate, acryloylmorpholine and the like can be used. In consideration of the glass transition temperature, it is preferable to use acrylic acid such as isobornyl (meth) acrylate, acrylomorpholine, acrylic acid, t-butyl acrylate, tetrahydrofuryl methacrylate, lauryl ( _C12 ) acrylate and cyclohexyl acrylate It is preferable to use at least one selected from the group consisting of

Such a monofunctional diluent monomer may contain from 5 to 55% by weight, preferably from 5 to 40% by weight. If the content is less than 5% by weight, it is difficult to expect an increase in adhesion with the plastic material, and if it exceeds 55% by weight, the curing shrinkage may be severe or the produced pressure-sensitive adhesive may become hard.

In addition, the present invention may further include a bifunctional or higher acrylate-based monomer within a range that does not deviate from the intended effect. The bifunctional or higher acrylate monomers serve to control the curing rate, and it is preferable to use an appropriate amount in consideration of the object of the present invention and the curing rate within the control range.

Examples of the acrylate monomer having two or more functional groups include 1,3-butanediol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, (Meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, propylene glycol di Acrylate, dipropylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, dicyclopentanedi (meth) acrylate, caprolactone modified dicyclopentenyl (Meth) acrylate, di (meth) acrylate, ethylene oxide modified di (meth) acrylate, bis (2-hydroxyethyl) isocyanurate di (Meth) acrylate, dimethylolcyclohexane diacrylate, ethylene oxide modified hexahydrophthalic acid diacrylate, tricyclodecane dimethanol acrylate, neopentyl glycol-modified trimethylolpropane diacrylate Bifunctional monomers such as maleic anhydride, maleic anhydride and maleic anhydride; (Meth) acrylate such as trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol tri (meth) acrylate, propionic acid modified dipentaerythritol tri Trifunctional monomers such as tri (meth) acrylate, tris (2-hydroxyethyl) isocyanurate tri (meth) acrylate, tris (acryloxyethyl) isocyanurate, glycerol tri ; Tetrafunctional monomers such as diglycerin tetra (meth) acrylate, pentaerythritol tetra (meth) acrylate, and ditrimethylol propane tetra (meth) acrylate; Pentafunctional monomers such as propionic acid-modified dipentaerythritol penta (meth) acrylate; And hexafunctional monomers such as dipentaerythritol hexa (meth) acrylate and caprolactone-modified dipentaerythritol hexa (meth) acrylate.

It is preferable that such bifunctional or higher functional acrylate monomer is contained in an amount of 5 wt% or less in 100 wt% of the whole composition.

The free radical photoinitiator has a function of sufficiently promoting the interior and surface hardening of the pressure-sensitive adhesive, and the type thereof is not particularly limited as long as it is known in the art.

Specific examples of the free radical photoinitiator include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin-n-butyl ether, benzoin isobutyl ether, acetophenone, hydroxydimethylacetophenone, Dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 4-chromenone 2-methyl-1-phenylpropan-1-one, 4-hydroxycyclophenyl ketone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl (2-hydroxyethoxy) phenyl-2- (hydroxy-2-propyl) ketone, benzo Anthraquinone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-t-aminobenzophenone, 4,4'-diethylaminobenzophenone, dichlorobenzophenone, - Butylanthra 2-amino thioxanthone, 2-amino thioxanthone, 2-chlorothioxanthone, 2,4-dimethyl thioxanthone, 2,4-diethyl thioxanthone, benzyldimethyl Ketene, diphenyl ketone benzyl dimethyl ketal, acetophenone dimethyl ketal, p-dimethylaminobenzoic acid ester, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, fluorene, triphenylamine, have. Further, commercially available products such as Darocur 1173, Igacure 184 and Igacure 907 (manufactured by Ciba) can also be used. These may be used alone or in combination of two or more.

The free radical photoinitiator may be used in an appropriate range in consideration of the radiation property, intensity, content of each component, etc. of the light source, and is preferably contained in an amount of 0.1 to 5% by weight based on the total content (100% by weight) of the pressure-sensitive adhesive composition.

The pressure-sensitive adhesive composition of the present invention can be cured to form a pressure-sensitive adhesive. Further, a transparent base film; The pressure-sensitive adhesive may include the pressure-sensitive adhesive formed on one side of the transparent substrate film.

The pressure-sensitive adhesive may have a thickness of 5 to 1000 mu m.

The transparent base film is not particularly limited as it is excellent in transparency, mechanical strength, thermal stability, moisture barrier property and the like.

The curing is not particularly limited as it is used in the art, but is generally photocuring using ultraviolet rays.

The light source in the polymerization using ultraviolet rays has a light emission distribution of 400 nm or less, preferably 150 to 400 nm, and more preferably 200 to 380 nm. The light source may be a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, , A black light lamp, a microwave-excited mercury lamp, and a metal halide lamp.

The intensity of the light irradiation can be appropriately adjusted according to the physical properties of the desired pressure-sensitive adhesive, and the amount of accumulated light useful for the activity of the free radical photoinitiator is preferably 10 to 5000 mJ / cm 2, more preferably 200 to 2000 mJ / cm 2. It is preferable to have an appropriate curing reaction time within the above range and to prevent the heat radiated from the lamp and the cohesive force of the cured product produced by heat generation during the polymerization reaction from deteriorating and deterioration of the yellowing or the support.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the present invention. Such variations and modifications are intended to be within the scope of the appended claims.

Manufacturing example : urethane Acrylate series Oligomer

Manufacturing example One

100 g of polypropylene diol was charged into a 2 L reactor equipped with a reflux condenser, a thermometer and a stirrer. After raising the temperature of the solution to 60 DEG C, 0.1 g of DBTDL (dibutyltin dilaurate) was added. 8 g of isophorone diisocyanate was slowly added over 30 minutes using a dropping funnel, and the reaction was carried out for 4 hours while maintaining the temperature of the reactor at 60 占 폚. A part of the above reaction product was taken and it was confirmed by IR analysis that the residual NCO peak was observed and that it was an oligomer containing a terminal NCO group.

Subsequently, 1 g of 4-hydroxybutyl acrylate (4HBA) and 3 g of 1-butyl-3- (2-hydroxyethyl) imidazolium bis (trifluoromethanesulfonyl) imide were added to the reaction product, And reacted at the same temperature for an additional 4 hours. A part of the reaction product was taken and it was confirmed by IR analysis that the residual NCO peak was not observed, and that the monofunctional urethane acrylate oligomer having an ionic functional group at its end (glass transition temperature (Tg) = -52 ° C) was confirmed.

Manufacturing example 2

Except that 3 g of 1-methyl-3- (2-hydroxyphenyl) imidazolium bis (trifluoromethanesulfonyl) imide was used instead of 3 g of 1-butyl- Hydroxyethyl) imidazolium hexafluorophosphate was used to prepare a monofunctional urethane acrylate oligomer having an ionic functional group at its terminal (glass transition temperature (Tg) = -54 ° C).

Manufacturing example 3

Except that 3 g of 1-butyl-3- (2-hydroxyethyl) imidazolium bis (trifluoromethanesulfonyl) imide was used in place of 3 g of 1-butyl- Hydroxypropyl) < / RTI > pyridinium hexafluorophosphate (Glass transition temperature (Tg) = -50 占 폚) having an ionic functional group at the terminal thereof was prepared.

Manufacturing example 4

Except that 3 g of 1-butyl-3- (2-thiol) imidazolium bis (trifluoromethanesulfonyl) imide was used instead of 3 g of 1-butyl- Ethyl) imidazolium bis (trifluoromethanesulfonyl) imide was used to prepare a monofunctional urethane acrylate oligomer having a terminal ionic functional group (glass transition temperature (Tg) = -51 ° C) .

compare Manufacturing example One: Bifunctionality urethane Acrylate series Oligomer

100 g of polypropylene diol was charged into a 2 L reactor equipped with a reflux condenser, a thermometer and a stirrer. After raising the temperature of the solution to 60 DEG C, 0.1 g of DBTDL (dibutyltin dilaurate) was added. 8 g of isophorone diisocyanate was slowly added thereto for 30 minutes using a dropping funnel and reacted for 4 hours while maintaining the temperature of the reactor at 60 ° C. After that, 2-hydroxyethyl acrylate (HEA) were added and reacted at the same temperature for an additional 4 hours.

A part of the reaction product was taken and it was confirmed by IR analysis that the residual NCO peak was observed and that it was an oligomer containing a terminal NCO group. In addition, it was confirmed that when the reaction product was partially reacted with isophorone diisocyanate, the viscosity did not increase, and it was confirmed that the resulting compound was a bifunctional urethane acrylate oligomer containing acrylic groups at both ends.

compare Manufacturing example 2: at the end Butoxy group Have Single sensory urethane Acrylate series Oligomer

Except that 2 g of 2-hydroxyethyl acrylate (HEA) and 0.8 g of n-butanol were used instead of 2 g of 2-hydroxyethylacrylate (HEA) to give a butoxy group at the terminal A monofunctional urethane acrylate oligomer was prepared.

A part of the reaction product was taken and it was confirmed by IR analysis that the residual NCO peak was observed and that it was an oligomer containing a terminal NCO group. In addition, when a part of the reaction product was taken to react with isophorone diisocyanate, it was confirmed that the resulting compound was a monofunctional urethane acrylate oligomer having a butoxy group at the terminal.

compare Manufacturing example 3: having a hydroxy group at the terminal Single sensory urethane Acrylate series Oligomer

Except that 1 g of 2-methacryloyloxyethyl isocyanate (MOI) was used instead of 2 g of 2-hydroxyethyl acrylate (HEA) to prepare a monofunctional urethane acrylate having a hydroxy group at the terminal Based oligomers.

A part of the reaction product was taken and it was confirmed by IR analysis that the residual NCO peak was observed and that it was an oligomer containing a terminal NCO group. Further, it was confirmed that when the reaction product was partially reacted with isophorone diisocyanate, the viscosity did not increase and that the resulting compound was a monofunctional urethane acrylate oligomer having a hydroxy group at the terminal.

Example One

(1) Pressure-sensitive adhesive composition

20 g of isobornyl acrylate (Tg = 94 占 폚), 20 g of t-butyl acrylate (Tg = 41 占 폚), 60 g of a free radical photoinitiator (product of Ciba Company, Darocur-1173) as monofunctional diluent monomer, Were mixed to prepare a pressure-sensitive adhesive composition.

(2) Production of adhesive film

The pressure-sensitive adhesive composition prepared in the above (1) was coated on a transparent base film coated with a silicone release agent to a thickness of 50 m, irradiated with ultraviolet rays at a velocity of 4 m / min (600 mJ / cm 2) The laminate was then irradiated with ultraviolet light at a speed of 4 m / min (600 mJ / cm 2) to prepare a fully cured pressure-sensitive adhesive film.

Example 2 to 8 and Comparative Example 1 to 3

A pressure-sensitive adhesive composition and a pressure-sensitive adhesive film were prepared in the same manner as in Example 1, except that the composition shown in Table 1 below was used.

division
(g) Urethane acrylate oligomer Monofunctional acrylate series
Monomer Free radical
Initiator Manufacturing example Comparative Manufacturing Example A-1 A-2 A-3 Example 1 Production Example 1 (60) - 20 20 - 2 Example 2 Production Example 2 (60) - 20 20 - 2 Example 3 Production Example 3 (60) - 20 20 - 2 Example 4 Production Example 4 (60) - 20 20 - 2 Example 5 Production Example 1 (60) - - 20 20 2 Example 6 Production Example 1 (60) - 20 - 20 2 Example 7 Production Example 1 (45) - 35 20 - 2 Example 8 Production Example 1 (75) - 5 20 - 2 Comparative Example 1 - Comparative Preparation Example 1 (60) 20 20 - 2 Comparative Example 2 - Comparative Preparation Example 2 (60) 20 20 - 2 Comparative Example 3 - Comparative Preparation Example 3 (60) 20 20 - 2 A-1: Isobornyl acrylate, Tg = 94 DEG C
A-2: t-Butyl acrylate, Tg = 41 DEG C
A-3: acrylomorpholine, Tg = 145 DEG C
Free radical photoinitiator: Ciba, Darocur-1173

Test Example

The physical properties of the pressure-sensitive adhesive composition and the pressure-sensitive adhesive film prepared in the above Examples and Comparative Examples were measured by the following methods, and the results are shown in Table 2 below.

1. Adhesion (N / 25 mm )

① Glass ( Glass ) Adhesion

The base film coated with the releasing agent laminated on the adhesive film was peeled off, and the PET base film which had not been subjected to releasing treatment was laminated. The pressure-sensitive adhesive sheet was cut into a size of 25 mm x 250 mm using a super-cutter, bonded to glass, fixed to the autograft, and peeled at 180 DEG peel at a speed of 300 m / min to measure adhesive strength.

② Triacetylcellulose ( TAC ) Film adhesion

A triacetyl cellulose (TAC) film was adhered to the glass using a double-sided tape to prepare a glass adhered to the TAC film. The substrate film coated with the release agent on the adhesive film prepared above was peeled off and then laminated on the TAC film. The pressure-sensitive adhesive sheet was cut into a size of 25 mm x 250 mm using a super cutter, and the TAC film was adhered to the adhered glass. The pressure-sensitive adhesive sheet was fixed to the autograft, and peeled off at 180 rpm at a rate of 300 m / min.

③ Polyethylene terephthalate ( PET ) Film adhesion

The glass adhered to the PET film was prepared by adhering the PET film to the glass using a double-sided tape. The substrate film on which the releasing agent coated on the adhesive film was peeled off was laminated on a PET film. The adhesive sheet was cut into a size of 25 mm x 250 mm using a super cutter, and the PET film was bonded to the adhered glass. The adhesive sheet was fixed to the autograft, and peeled off at 180 ° PEEL at a rate of 300 m / min.

2. Heat resistance

The substrate film coated with the releasing agent laminated on the pressure-sensitive adhesive film was peeled off, and then laminated on a non-releasable PET (38 um film made by Toray Advanced Materials Co., Ltd.). The pressure-sensitive adhesive sheet was cut into A4 size using a super cutter, bonded to glass, treated at 50 ° C for 5 minutes under an atmospheric pressure of 5 atm for 20 hours, and left in a 90 ° heat oven for 250 hours.

◎: No defects such as bubbles after heat resistance evaluation.

○: After the heat resistance evaluation, less than 10 bubbles of less than 1um occurred on the outside.

△: 10 or more bubbles of 1um or less occurred on the outer edge after the evaluation of heat resistance.

X: Bubbles and floating occurred after heat resistance evaluation.

3. Humidity Durability

The substrate film coated with the releasing agent laminated on the adhesive film was peeled off and then laminated on the PET film not subjected to releasing treatment. The pressure-sensitive adhesive sheet was cut into A4 size using a super cutter and bonded to glass. The adhesive sheet was treated with an autoclave at 50 DEG C for 20 minutes under a pressure of 5 atm. Then, the pressure-sensitive adhesive sheet was allowed to stand in a humidity oven at 60 DEG C and 60RH% for 100 hours.

◎: No defects such as bubbles after the evaluation of moisture heat resistance.

○: Bubbles less than 1 μm occurred on the outer edge after the evaluation of heat resistance.

Δ: 10 or more bubbles of 1 μm or less occurred on the outer periphery after the evaluation of wet heat resistance.

X: Bubbles and floating occurred after evaluation of heat resistance.

division Adhesive force (N / 25mm) Heat resistance Humidity Durability GLASS TAC film PET film Example 1 33.2 21.5 25.3 ◎ ○ Example 2 35.2 20.8 26.2 ◎ ○ Example 3 33.3 22.0 24.9 ◎ ○ Example 4 32.1 20.9 23.5 ◎ ○ Example 5 35.3 25.0 26.7 ◎ ○ Example 6 32.1 23.2 23.8 ◎ ○ Example 7 27.2 17.5 16.3 ○ ○ Example 8 28.0 18.7 18.8 ○ ○ Comparative Example 1 5.2 2.3 3.4 ○ × Comparative Example 2 18.5 9.8 12.5 × △ Comparative Example 3 20.7 12.9 14.5 △ ×

As shown in Table 2, according to the present invention, a monofunctional urethane acrylate oligomer having an ionic functional group at the terminal thereof; Monofunctional acrylate monomers; And the free radical initiator of Examples 1 to 8 were superior to those of Comparative Examples 1 to 3 in terms of adhesion to inorganic materials as well as plastic materials and that they were excellent in durability such as heat resistance and wet heat resistance there was.

Claims

A monofunctional urethane acrylate oligomer having an ionic functional group at the terminal; Monofunctional acrylate monomers; And a free radical initiator.

The pressure-sensitive adhesive composition for optical use according to claim 1, wherein the monofunctional urethane acrylate oligomer is obtained by polymerizing an ionic compound having a hydroxyl group or a thiol group and an acrylate monomer having a hydroxyl group, and a polyol, a diisocyanate compound, .

3. The composition of claim 2, wherein the ionic compound comprises a cation having a hydroxy or thiol group; A fluorine-containing inorganic salt or an anion of a fluorine-containing organic salt.

[4] The ionic compound according to claim 3, wherein the ionic compound is at least one selected from the group consisting of 1-butyl-4- (3-hydroxymethyl) pyridinium tetrafluoroborate, 1 -butyl 4- (3-hydroxymethyl) pyridinium hexafluorophosphate, (3-hydroxypropyl) pyridinium trifluoromethanesulfonate, 1-butyl-4- (3-hydroxypropyl) pyridinium tetrafluoroborate, 1-butyl- Butyl-4- (3-hydroxypropyl) pyridinium bis (pentafluoroethanesulfonyl) imide, 1-butyl- Hydroxypyridinium tetrafluoroborate, 1- (3-mercaptopropyl) pyridinium tetrafluoroborate, 1- (3-mercaptopropyl) pyridinium hexafluorophosphate, 1- 3-mercaptopropyl) pyridinium hexafluorophosphate, 1- (3-mercaptopropyl) pyridinium trifluoromethanesulfonate, 1- (3-mercaptopropyl) (Pentafluoroethanesulfonyl) imide, 1-ethyl-3-hydroxymethylindole hexafluorophosphate (trifluoromethanesulfonyl) imide, 1- Ethyl-6-hydroxyindole hexafluorophosphate, 1-methyl-3- (2-hydroxyethyl) imidazolium hexafluorophosphate, Methyl-3- (2-hydroxyethyl) imidazolium trifluoromethanesulfonate, 1-methyl-3- (2-hydroxyethyl) imidazolium trifluoromethanesulfonate, Imidazolium bis (trifluoromethanesulfonyl) imide, 1-methyl-3- (2-methyl-2-hydroxyethyl) imidazolium (Trifluoromethanesulfonyl) imide, 1-methyl-3- (2,2-dimethyl-2-hydroxyethyl) imidazolium bis (trifluoromethanesulfonyl) 3- (2-hydroxyethyl) imidazolium (Trifluoromethanesulfonyl) imide, 1-butyl-3- (2-hydroxyethyl) imidazolium tetrafluoroborate, 1-butyl-3- (2- hydroxyethyl) imidazolium hexa Butyl-3- (2-hydroxyethyl) imidazolium trifluoromethanesulfonate, 1-butyl-3- (2-hydroxyethyl) imidazolium trifluoromethanesulfonate, (2,2-dimethyl-3-hydroxypropyl) imidazolium bis (trifluoromethanesulfonyl) imide, 1-octyl-3- (2-hydroxyethyl) imidazolium chloride, 1-tetradecyl-3- (2,2-dimethyl-3-hydroxypropyl) imidazolium (2-hydroxyethyl) imidazolium hexafluorophosphate, 1-hexyl-2-methyl-3- 1-butyl-3- (2-thiol ethyl) imidazolium bis (trifluoromethane) 1- (12-mercaptododecyl) -3-methylimidazolium hexafluorophosphate, 1,3-dimethyl-2-mercapto-1,4,5,6-tetrahydropyri 1-hydroxymethylpyrazolium tetrafluoroborate, and 1-hydroxymethyl-2-methylpyrazolinium hexafluorophosphate, which are selected from the group consisting of sodium bis (trifluoromethanesulfonyl) imide, 1-hydroxymethyl pyrazolium tetrafluoroborate, Sensitive adhesive composition for optical use.

The positive resist composition according to claim 1, which comprises 40 to 80% by weight of a monofunctional urethane acrylate oligomer having an ionic functional group at the terminal; 5 to 55% by weight monofunctional acrylate monomer; And 0.1 to 5% by weight of a free radical initiator.