KR20200049385A - Pressure-sensitive adhesive composition, surface protective film and method of manufacturing organic light emitting electronic device - Google Patents

Abstract

The present invention relates to an adhesive composition, to a surface protection film which can prevent contamination of an adherend surface from external environment during a process, and to a manufacturing method of an organic light-emitting electronic device. The adhesive composition comprises: a (meth)acrylate resin containing an unsaturated group; a photo-initiator; and an isocyanate-based curing agent.

Description

Manufacturing method of pressure-sensitive adhesive composition, surface protective film and organic light emitting electronic device {PRESSURE-SENSITIVE ADHESIVE COMPOSITION, SURFACE PROTECTIVE FILM AND METHOD OF MANUFACTURING ORGANIC LIGHT EMITTING ELECTRONIC DEVICE}

The present application relates to a pressure-sensitive adhesive composition, a surface protective film comprising the same, and a method for manufacturing an organic light emitting electronic device.

The plastic substrate used as the substrate material of the flexible display has a problem that gas barrier properties such as moisture and oxygen are remarkably low. Accordingly, in the related art, a barrier film to which various materials and structures are applied is formed on the substrate to improve the problem of the plastic substrate.

However, in recent years, the development of a surface protection film for a process capable of protecting a thin film encapsulation (TFE) layer during the manufacturing process of a flexible optical device is required as the existing barrier film is not used. The surface protection film for the process is a film that protects the thin film encapsulation layer for a while and is removed after being attached to the thin film encapsulation layer during the process.

Registered Patent Publication No. 10-2007-0041238

The surface protection film requires low adhesion to minimize damage to the surface of the device when peeling off the surface of the device. Conventionally, a silicone-based pressure-sensitive adhesive layer having a residue is used so that the surface of the pressure-sensitive adhesive layer has a hydrophobic property, or a hydrophobic material is added to the pressure-sensitive adhesive layer in order to realize low adhesion of the surface protection film.

However, due to the low adhesive force, there is a problem in that bubbles or foreign substances are trapped in the step portion of the device panel, resulting in display failure of the device, and the thickness of the pressure-sensitive adhesive layer has to be designed to 75 μm to solve the above problem.

However, if the thickness of the pressure-sensitive adhesive layer is 75㎛ level, there is a problem that the thickness of the prepared pressure-sensitive adhesive layer is not uniform. Accordingly, when inspecting the appearance of the device panel in the state where the protective film is attached, there was a problem that the staining phenomenon (mura phenomenon) occurred on the surface of the panel and the accuracy of device inspection was deteriorated.

An exemplary embodiment of the present specification is a (meth) acrylate resin containing an unsaturated group; Photoinitiators; And it provides an adhesive composition comprising an isocyanate-based curing agent.

One embodiment of the present specification is a base film; And a pressure-sensitive adhesive layer provided on the base film, wherein the pressure-sensitive adhesive layer includes (meth) acrylate resin; And it provides a surface protective film containing an unsaturated group.

An exemplary embodiment of the present specification is an organic light emitting device; And an adhesive layer provided on the organic light emitting element, wherein the adhesive layer comprises (meth) acrylate resin; And it provides an organic light emitting electronic device comprising an unsaturated group.

An exemplary embodiment of the present specification is the step of attaching the above-described surface protective film on the sealing layer of the organic light emitting device so that the pressure-sensitive adhesive layer is in contact with the sealing layer; Curing the pressure-sensitive adhesive layer; And removing the surface protection film.

The pressure-sensitive adhesive layer included in the surface protection film of the present invention has excellent wetting on the surface of the adherend before curing, and has a low modulus to prevent air bubbles in the stepped portions between panels even with a thickness of 40 μm or less.

The surface protective film of the present invention has a high adhesion to the surface of the adherend before curing, and thus can prevent contamination of the adherend surface from the external environment during the process.

The surface protective film of the present invention has a low adhesive strength to the surface of the adherend after curing, so it is possible to remove the surface protective film with a low peeling force, but after removal, there is little residue of the adhesive on the surface of the adherend, and after removal, damage or contamination of the adherend surface Can be prevented.

1 is a base film 110; Pressure-sensitive adhesive layer 120; And it shows a surface protective film consisting of a protective film 130.
FIG. 2 illustrates a state in which the protective film is removed from the surface protective film of FIG. 1 and the pressure-sensitive adhesive layer 120 of the surface protective film is attached to the organic light emitting device 510.
3 illustrates a structure according to an exemplary embodiment of the organic light emitting device 510 of FIG. 2.

Hereinafter, preferred embodiments of the present application will be described. However, embodiments of the present application may be modified differently from the following description, and the scope of the present application is not limited to the following description. Embodiments of the present application are provided to describe the present application in detail to those having average knowledge in the art.

In the present specification, 'p to q' means a range of 'p or more and q or less'.

In the present specification, that the polymer includes a monomer means that the monomer participates in a polymerization reaction and is included as a repeating unit in the polymer.

In the present specification, "a unit derived from a compound" means a state in which the compound is polymerized and bonded to the polymer, and accordingly, all or part of two or more substituents in the structure of the compound are eliminated, and the polymer is in its position. Radicals for bonding with other units of may be located.

In the present specification, "monomer unit" means a state in which the compound is polymerized and bound in the polymer.

In this specification, a glass plate means alkali-free glass (NEG, OA-21), unless otherwise specified.

In this specification, when it is said that one layer is "equipped" on one side of another layer, this includes not only the case where one layer is in contact with one side of the other layer, but also when there is another layer between the two layers.

In the present specification, when a part “includes” a certain component, it means that the component may further include other components, rather than excluding other components, unless otherwise specified. Furthermore, when a part includes a certain component, it means that at least one of the components is included.

In the present specification, the weight part of a component in the composition means the sum of the weight parts of the two or more substances when the component is composed of two or more substances.

In the present specification, the weight part means a weight ratio.

In one embodiment of the present specification, the weight average molecular weight can be measured by GPC (Gel Permeation Chromatography).

This specification is (meth) acrylate resin containing an unsaturated group; Photoinitiators; And it provides an adhesive composition comprising an isocyanate-based curing agent.

When the pressure-sensitive adhesive layer formed using the pressure-sensitive adhesive composition is used by attaching the pressure-sensitive adhesive layer to the surface of the electronic device during the process, the adhesive strength between the pressure-sensitive adhesive layer and the surface of the electronic device is high to prevent contamination and damage of the electronic device from the external environment. Can be.

In addition, since the pressure-sensitive adhesive layer according to the present application has a low surface and adhesive strength after curing, the pressure-sensitive adhesive layer is cured upon completion of the process to peel the pressure-sensitive adhesive layer from the electronic component with a lower peel force, thereby preventing damage to the electronic component. Can be.

Moreover, when the pressure-sensitive adhesive composition according to the present application is used, even when an pressure-sensitive adhesive layer having a thickness of 40 µm or less is formed, characteristics of a soft pressure-sensitive adhesive layer can be realized due to low modulus.

In one embodiment, when the number of moles of the hydroxy group contained in the (meth) acrylate resin containing the unsaturated group is n ₁ and the number of moles of isocyanate group contained in the isocyanate curing agent is n ₂ , n ₂ / n ₁ is 1 to 3.5.

In one embodiment, the n ₂ / n ₁ is 1 or more; 1.5 or higher; Or 2 or more.

In one embodiment, the n ₂ / n ₁ is 3.5 or less; 3 or less; Or 2.5 or less.

When the n ₂ / n ₁ is less than ₁ , the crosslinking degree of the (meth) acrylate resin containing an unsaturated group during thermal curing of the pressure-sensitive adhesive composition is low, and the adhesive strength after heat curing of the pressure-sensitive adhesive layer is too high, thereby reworking the surface protection film during the process. It can be difficult.

When the NCO / OH is greater than 3.5, the crosslinking degree of the (meth) acrylate resin containing an unsaturated group during thermal curing of the pressure-sensitive adhesive composition is high, and the adhesive strength of the pressure-sensitive adhesive layer containing a heat-cured product of the pressure-sensitive adhesive composition may be lowered.

In one embodiment, the glass transition temperature (Tg) of the pressure-sensitive adhesive layer containing the heat-UV cured product of the pressure-sensitive adhesive composition is higher than the glass transition temperature (Tg) of the pressure-sensitive adhesive layer containing the heat-cured product of the pressure-sensitive adhesive composition.

In the present specification, 'cured' means a material in which a component capable of participating in a curing reaction is cured or crosslinked through a curing reaction.

In the present specification, 'thermoset of the adhesive composition' means a material in which the (meth) acrylate resin containing the unsaturated group, the isocyanate-based curing agent, and other curable components in the composition are cured or crosslinked through a thermosetting reaction. Can be.

In one embodiment, the heat curing condition in the "thermoset of the adhesive composition" may be to heat the temperature of 100 ℃ to 140 ℃ for 2 minutes to 5 minutes.

In the present specification, the 'heat-UV cured product of the adhesive composition' refers to the (meth) acrylate resin containing the unsaturated group, the isocyanate-based curing agent, and other curable components in the composition, sequentially heat curing reaction and UV curing reaction. It may mean a cured or crosslinked material.

In one embodiment, the heat-UV curing condition of the 'thermo-UV cured product of the adhesive composition' may be dried at a temperature of 110? For 4 minutes, and then an ultraviolet ray of 300 mJ / cm ² may be applied with an LED lamp of 365 nm wavelength. have.

In one embodiment, the heat-UV curing condition of the 'thermo-UV cured product of the adhesive composition' was dried for 4 minutes at a temperature of 110 ?, and then applied 1,000 mJ / cm ² of ultraviolet light with an LED lamp of 365 nm wavelength. Can be.

In one embodiment, the heat-UV curing condition of the 'thermo-UV cured product of the adhesive composition' was dried at a temperature of 110? For 4 minutes, and then 2,000 mJ / cm ² of ultraviolet light was applied to the LED lamp having a wavelength of 365 nm. Can be.

In one embodiment, the glass transition temperature (Tg) of the pressure-sensitive adhesive layer containing a thermoset of the pressure-sensitive adhesive composition is -50 ° C or higher; -45 ° C or higher; Or -40 ° C or higher.

In one embodiment, the glass transition temperature (Tg) of the pressure-sensitive adhesive layer containing a thermoset of the pressure-sensitive adhesive composition is -10 ° C or less; -15 ° C or lower; Or -20 ° C or lower.

In one embodiment, the glass transition temperature of the pressure-sensitive adhesive layer containing a heat-UV cured product of the pressure-sensitive adhesive composition is 0 ° C or higher; 5 ° C or higher; Or 10 ° C or higher.

In one embodiment, the glass transition temperature of the pressure-sensitive adhesive layer containing a heat-UV cured product of the pressure-sensitive adhesive composition is 75 ° C or less; 60 ° C. or less; Or 45 ° C or lower.

The (meth) acrylate resin containing the unsaturated group is a random copolymer (Random Copolymer) having a form in which monomers are mixed with each other without a rule, a block copolymer (Block Copolymer) in which blocks arranged in a certain section are repeated, or a monomer alternately. It may be an alternating copolymer having a form of being repeatedly polymerized.

The (meth) acrylate resin containing the unsaturated group is a common polymerization method in this field, for example, solution polymerization, photo polymerization, bulk polymerization, suspension polymerization. ) Or emulsion polymerization.

The (meth) acrylate resin containing the unsaturated group is a unit derived from (meth) acrylate containing a hydroxyl group; And a unit derived from a (meth) acrylate containing an unsaturated group as a monomer unit.

In one embodiment, the unit derived from the (meth) acrylate containing the hydroxy group is 1 mol% or more compared to the total monomer units contained in the (meth) acrylate resin containing the unsaturated group; Or 2 mol% or more.

In one embodiment, the unit derived from the (meth) acrylate containing the hydroxy group is 10 mol% or less compared to the total monomer units contained in the (meth) acrylate resin containing the unsaturated group; 8 mol% or less; Or 6 mol% or less.

When the unit derived from the (meth) acrylate containing the hydroxy group is included below the above range, the crosslinking degree after the thermal curing of the (meth) acrylate resin containing the unsaturated group is lowered, and the adhesive strength after the thermal curing of the pressure-sensitive adhesive layer is too high. Rework of the surface protection film during the process can be difficult.

When the unit derived from the (meth) acrylate containing the hydroxy group is included in an amount exceeding the above range, the crosslinking degree after thermal curing of the (meth) acrylate resin containing the unsaturated group is increased, and the glass transition temperature (Tg) of the resin is increased. Can be elevated. Accordingly, since the adhesive strength of the pressure-sensitive adhesive layer containing a thermoset of the pressure-sensitive adhesive composition may be low, it is preferable to satisfy the above range.

In one embodiment, the unit derived from the (meth) acrylate containing the unsaturated group is 10 mol% or more compared to the total monomer unit contained in the (meth) acrylate resin containing the unsaturated group; 12 mol% or more; 14 mol% or more; Or 16 mol% or more.

In one embodiment, the unit derived from the (meth) acrylate containing the unsaturated group is 30 mol% or less compared to the total monomer units contained in the (meth) acrylate resin containing the unsaturated group; 28 mol% or less; 26 mol% or less; Or 24 mol% or less.

The unsaturated group of the (meth) acrylate resin containing the unsaturated group may react with a photoinitiator during UV curing to increase the degree of crosslinking of the resin. When the unit derived from the (meth) acrylate containing the unsaturated group is included below the above range, the crosslinking degree after heat-UV curing of the (meth) acrylate resin containing the unsaturated group is lowered, so that the heat-UV hardness of the pressure-sensitive adhesive composition The adhesive strength of the pressure-sensitive adhesive layer containing the cargo may be high.

When the unit derived from the (meth) acrylate containing the unsaturated group is included in an amount exceeding the above range, the glass transition temperature after heat curing of the (meth) acrylate resin containing the unsaturated group is increased, and the heat composition of the pressure-sensitive adhesive composition is included. The adhesive strength of the pressure-sensitive adhesive layer may be lowered.

In one embodiment, the (meth) acrylate resin containing the unsaturated group further includes a unit derived from an alkyl (meth) acrylate.

In one embodiment, the (meth) acrylate resin containing the unsaturated group is a unit derived from an alkyl (meth) acrylate; Unit derived from (meth) acrylate containing a hydroxy group; And a unit derived from (meth) acrylate containing an unsaturated group.

This, (meth) acrylate resin containing the unsaturated group is a unit derived from an alkyl (meth) acrylate; Unit derived from (meth) acrylate containing a hydroxy group; And it means that the unit derived from the (meth) acrylate containing an unsaturated group is a linearly polymerized polymer.

In one embodiment, the weight average molecular weight of the (meth) acrylate containing the unsaturated group is 400,000 g / mol or more; 450,000 g / mol or more; It is preferably 500,000 g / mol or more.

In one embodiment, the weight average molecular weight of the (meth) acrylate containing the unsaturated group is 700,000 g / mol or less; 650,000 g / mol or less; Or 600,000 g / mol or less.

When the molecular weight of the (meth) acrylate containing the unsaturated group exceeds the above range, the glass transition temperature of the (meth) acrylate resin containing the unsaturated group after heat curing becomes too high, so that the adhesive strength of the pressure-sensitive adhesive composition after heat curing may be too low. Therefore, it is preferable to satisfy the above range.

The alkyl group included in the alkyl (meth) acrylate may be straight chain or branched chain. The alkyl group included in the alkyl (meth) acrylate may have 1 to 20 carbon atoms.

The alkyl (meth) acrylate is methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, t- Butyl (meth) acrylate, sec-butyl (meth) acrylate, 1-methylbutyl (meth) acrylate, 2-methylbutyl (meth) acrylate, 1-ethylbutyl (meth) acrylate, 2-ethylbutyl (Meth) acrylate, 3-ethylbutyl (meth) acrylate, 1-propylbutyl (meth) acrylate, n-pentyl (meth) acrylate, 1-ethylhexyl (meth) acrylate, 2-ethylhexyl ( Meth) acrylate, 3-ethylhexyl (meth) acrylate, 4-ethylhexyl (meth) acrylate, 1-propylhexyl (meth) acrylate, 2-propylhexyl (meth) acrylate, 3-propylhexyl (Meth) acrylate, n-heptyl (meth) acrylate, 1-methylheptyl (meth) acrylate, 2-methylheptyl (meth) acrylate, 3-methylheptyl (meth) acrylate, 4-methylheptyl (meth) acrylate, 5-methylheptyl (meth) acrylate, 1-ethylheptyl (meth) acrylate, 2-ethylheptyl (meth) acrylate, 3-ethylheptyl (meth) acrylate, 4-ethylheptyl (meth) acrylate, 1-propylheptyl (meth) acrylate, 2-propylheptyl (meth) acrylate, 3-propylheptyl (meth) acrylate, 4-propylheptyl (meth) acrylate, n-octyl (meth) acrylate, n-nonyl (meth) acrylate, n-decyl (meth) acrylate, lauryl ( Meth) acrylate, tridecyl (meth) acrylate, tetradecyl (meth) acrylate, pentadecyl (meth) acrylate, hexadecyl (meth) acrylate, heptadecyl (meth) acrylate and stearyl (meth) It may be one or two or more selected from the group consisting of acrylates. I, and the like.

In one embodiment, when two or more units derived from the alkyl (meth) acrylate are used, the content of each monomer unit may be appropriately selected.

In one embodiment, the (meth) acrylate containing the hydroxy group may be hydroxyalkyl (meth) acrylate.

In one embodiment, the hydroxyalkyl (meth) acrylate may be a compound in which at least one hydrogen of the alkyl group of the alkyl (meth) acrylate is substituted with a hydroxy group.

In one embodiment, the number of hydroxy groups included in one molecule of the hydroxyalkyl (meth) acrylate may be 1 to 4. In one embodiment, the number of hydroxy groups contained in one molecule of the hydroxyalkyl (meth) acrylate is one.

The hydroxyalkyl (meth) acrylate is 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) ) Acrylate, 8-hydroxyoctyl (meth) acrylate, 2-hydroxyethylene glycol (meth) acrylate and 2-hydroxypropylene glycol (meth) acrylate. May include, but is not limited to.

The (meth) acrylate resin containing the unsaturated group may be a (meth) acrylate resin containing an alkenyl group.

The (meth) acrylate containing the unsaturated group may be represented by Formula 1 below.

[Formula 1]

In Chemical Formula 1,

R ₁ is hydrogen; Or a methyl group,

R ₂ is hydrogen; Or a methyl group,

L ₁ is a straight chain or branched alkylene group,

L ₂ is a straight-chain or branched alkylene group.

In one embodiment, L ₁ is a straight-chain or branched C1-C10 alkylene group.

In one embodiment, L ₂ is a straight-chain or branched C1-C10 alkylene group.

In one embodiment, the unit derived from the (meth) acrylate containing the unsaturated group may be represented by the following formula (2).

[Formula 2]

In Chemical Formula 2,

는 상기 불포화기를 포함하는 (메트)아크릴레이트 수지에 포함되는 다른 구조 단위와 연결하는 부위이고,

Is a site connecting with other structural units included in the (meth) acrylate resin containing the unsaturated group,

R ₁ is hydrogen; Or a methyl group,

R ₂ is hydrogen; Or a methyl group,

L ₁ is a straight chain or branched alkylene group,

L ₂ is a straight-chain or branched alkylene group.

The isocyanate curing agent refers to an organic compound containing an isocyanate group capable of reacting with an OH group.

The isocyanate curing agent may be one kind or two or more kinds. When two or more isocyanate curing agents are used, the mixing ratio of the curing agents can be appropriately selected within a range that does not affect the effect of the present invention.

Any suitable polyfunctional isocyanate compound may be used as long as it is capable of reacting with the (meth) acrylic resin containing the unsaturated group.

The average isocyanate group equivalent of the isocyanate curing agent is 1 to 3; 1 to 2; Or 1 to 1.5. The equivalent weight of the isocyanate group means the number of isocyanate groups per molecule of the isocyanate curing agent, and the equivalent weight of the average isocyanate group means the average value of the equivalent weight of each isocyanate group of the isocyanate curing agent.

In one embodiment, the isocyanate-based curing agent is 2,4- or 4,4'-methylene diphenyl diisocyanate (MDI), xylylene diisocyanate (XDI), m- or p-tetramethylxylylene diisocyanate ( TMXDI), toluylene diisocyanate (TDI), di- or tetra-alkyldiphenylmethane diisocyanate, 3,3'-dimethyldiphenyl-4,4'-diisocyanate (TODI), 1,3-phenylene di Isocyanate, 1,4-phenylene diisocyanate, naphthalene diisocyanate (NDI), 4,4'-dibenzyldiisocyanate, hydrogenated MDI (H12MDI), 1-methyl-2,4-diisocyanatocyclohexane, 1, 12-diisocyanatododecane, 1,6-diisocyanato-2,2,4-trimethylhexane, 1,6-diisocyanato-2,4,4-trimethylhexane, isophorone diisocyanate (IPDI), Tetramethoxybutane-1,4-diisocyanate, butane-1,4-diisocyanate, hexane-1,6-diisocyanate (HDI), Dimer fatty acid diisocyanate, dicyclohexyl methane diisocyanate, cyclohexane-1,4-diisocyanate, and but may include one or two or more selected from the group consisting of ethylene diisocyanate, and the like.

In one embodiment, the hydroxyl value of the (meth) acrylate resin containing the unsaturated group is 7 mgKOH / g or more; 8 mgKOH / g or more; Or 9 mgKOH / g or more.

In one embodiment, the hydroxyl value of the (meth) acrylate resin containing the unsaturated group is 15 mgKOH / g or less; 14 mgKOH / g or less; 13 mgKOH / g or less; Or 12 mgKOH / g or less.

The hydroxyl value (OH value, mgKOH / g) means the amount (mg) of potassium hydroxide (KOH) required to acetylate 1 g of the compound and neutralize acetic acid generated by hydrolysis.

When the hydroxyl value of the (meth) acrylate containing the unsaturated group satisfies the above range, even when the process is performed in a high temperature and humid environment, when removing the pressure-sensitive adhesive layer at the completion of the process, the residual amount is small to prevent contamination of the surface of the adherend Since an adhesive layer capable of being formed is formed, it is preferable to satisfy the above range.

In one embodiment, the hydroxyl value of the (meth) acrylate resin containing the unsaturated group can be measured by a titration method. The titration method was described in the following examples.

The pressure-sensitive adhesive composition includes a photoinitiator. When the pressure-sensitive adhesive composition includes a photoinitiator, the residual adhesion rate of the pressure-sensitive adhesive layer can be implemented to 80% or more.

In one embodiment, the pressure-sensitive adhesive composition may further include a plasticizer. If the pressure-sensitive adhesive composition does not include a photoinitiator in a state including a plasticizer, the residual adhesive strength may be less than 80% due to the residual material of the plasticizer.

The photoinitiator is selected from the group consisting of triazine compounds, biimidazole compounds, acetophenone compounds, O-acyloxime compounds, thioxanthone compounds, phosphine oxide compounds, coumarin compounds and benzophenone compounds 1 It may be a species or two or more, but is not limited thereto.

The triazine-based compound is 2,4-trichloromethyl- (4'-methoxyphenyl) -6-triazine, 2,4-trichloromethyl- (4'-methoxystyryl) -6-triazine, 2,4-trichloromethyl- (fiflonil) -6-triazine, 2,4-trichloromethyl- (3 ', 4'-dimethoxyphenyl) -6-triazine, 2,4-trichloro Methyl- (4'-ethylbiphenyl) -6-triazine, 2,4-trichloromethyl- (4'-methylbiphenyl) -6-triazine, and the like, but is not limited thereto.

The biimidazole compound is 2,2'-bis (2-chlorophenyl) -4,4 ', 5,5'-tetraphenyl biimidazole, 2,2'-bis (2,3-dichlorophenyl)- 4,4 ', 5,5'-tetraphenylbiimidazole, and the like, but is not limited thereto.

The acetophenone compound is 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, 4- (2-hydroxyethoxy) -phenyl (2-hydroxy) propyl ketone, 1-hydroxycyclohexylphenylketone, 2,2-dimethoxy-2-phenylacetophenone, 2-methyl- (4-methylthio Phenyl) -2-morpholino-1-propan-1-one (Irgacure-907), 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one (Irgacure- 369), but is not limited thereto.

The O-acyloxime-based compound may be Irgacure OXE 01, Irgacure OXE 02, etc. of Ciba Geigy, but is not limited thereto.

The thioxanthone-based compound may be 2,4-diethyl thioxanthone, 2-chloro thioxanthone, isopropyl thioxanthone, diisopropyl thioxanthone, and the like, but is not limited thereto.

The phosphine oxide-based compound is 2,4,6-trimethylbenzoyldiphenyl phosphine oxide, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentyl phosphine oxide, bis (2,6- Dichlorobenzoyl) propyl phosphine oxide, and the like, but is not limited thereto.

The coumarin-based compound is 3,3'-carbonylvinyl-7- (diethylamino) coumarin, 3- (2-benzothiazolyl) -7- (diethylamino) coumarin, 3-benzoyl-7- (di Ethylamino) coumarin, 3-benzoyl-7-methoxy-coumarin, and the like, but is not limited thereto.

The benzophenone-based compound may be 4,4'-bis (dimethylamino) benzophenone, 4,4'-bis (diethylamino) benzophenone, but is not limited thereto.

In one embodiment, the photoinitiator is 1 part by weight or more with respect to 100 parts by weight of the solid content of the (meth) acrylate resin containing the unsaturated group; Or 2 parts by weight or more.

In one embodiment, the photoinitiator is 5 parts by weight or less based on 100 parts by weight of the solid content of the (meth) acrylate resin containing the unsaturated group; Or 4 parts by weight or less. When the photoinitiator is included in an amount exceeding the above range, reliability of the pressure-sensitive adhesive layer is lowered, and the pressure-sensitive adhesive layer may be yellowed.

The pressure-sensitive adhesive composition may further include a solvent. As the solvent, an organic solvent generally used may be used without limitation as long as it can dissolve the resin and the curing agent.

Examples of the solvent include ethyl acetate, dimethylformamide, diethylformamide, dimethylacetamide, dimethylsulfoxide, tetrahydrofuran, acetone, methylethylketone, methylisobutylketone, dioxane, cyclohexanone, Benzene, toluene, xylene, ethyl acetate, butyl acetate, ethanol, isopropanol, n-butanol, and the like can be used, but are not limited thereto.

In one embodiment, the concentration of the solid content of the pressure-sensitive adhesive composition is 35% by weight or more; Or 40% or more.

In one embodiment, the concentration of the solid content of the pressure-sensitive adhesive composition is 60% by weight or less; 55% by weight or less; Or 50% or less.

If the solvent is included in the composition below the above range, the viscosity of the pressure-sensitive adhesive composition may be high, thereby staining the appearance upon coating of the pressure-sensitive adhesive composition, and when it exceeds the above range, it is difficult to coat the pressure-sensitive adhesive composition to an appropriate thickness, thus satisfying the above range. It is preferred.

In the present specification, solid content means a component excluding a solvent among components constituting the composition. In an exemplary embodiment, the solid content may mean remaining components when the composition is dried in an oven to remove all of the solvent.

The pressure-sensitive adhesive composition may further include a catalyst. The catalyst may serve to promote curing. The catalyst serves to improve the reaction rate in order to form sufficient crosslinking upon curing the adhesive composition.

In one embodiment, the catalyst is 1ppm to 100ppm with respect to the content of solids in the pressure-sensitive adhesive composition; Or it may be included in 20ppm to 80ppm.

The catalyst may be a tin-based catalyst, a lead-based catalyst, salts of organic and inorganic acids, organic metal derivatives, amine-based catalysts, diazabicyclodecene-based catalysts, etc., but is not limited thereto. In an exemplary embodiment, a tin-based compound such as dibutyl tin dilaurate (DBTDL) may be used.

The pressure-sensitive adhesive composition may further include a plasticizer. The plasticizer can be used to improve the flexibility and processability of the resin.

In one embodiment, the plasticizer is a citrate-based plasticizer; Trimellitic acid ester plasticizers; Pyromellitic acid ester plasticizers; Phthalic ester plasticizers; And it may be one or two or more selected from the group consisting of adipic acid ester plasticizer, but is not limited thereto, and a known plasticizer may be used.

The citrate plasticizer (citric acid ester plasticizer) may be triethyl citrate, acetyl triethyl citrate, tributyl citrate, acetyl tributyl citrate (ATBC) or acetyl trioctyl citrate, but is not limited thereto. .

The trimellitic acid ester plasticizer is trimellitic acid tri (n-octyl), trimellitic acid tri (2-ethylhexyl), trimellitic acid triisooctyl, trimellitic acid triisononyl, trimellitic acid triisodecyl, etc. It may be a trimellitic acid trialkyl ester, and the like, but is not limited thereto.

The pyromellitic acid ester plasticizer may be a pyromellitic acid tetraalkyl ester such as tetra (n-octyl) pyromellitate or tetra (2-ethylhexyl) pyromellitate, but is not limited thereto.

The phthalic ester plasticizer may be di-n-octyl phthalate, di-2-ethylhexyl phthalate, diisononyl phthalate, diisodecyl phthalate, and the like, but is not limited thereto.

The adipic acid ester plasticizer may be di-n-octyl adipic acid, di-2-ethylhexyl adipic acid, diisononyl adipic acid, and the like, but is not limited thereto.

In one embodiment, the plasticizer is 5 parts by weight or more with respect to 100 parts by weight of the solid content of the (meth) acrylate resin containing the unsaturated group; 10 parts by weight or more; 15 parts by weight or more; Preferably, 18 parts by weight or more may be included. When the pressure-sensitive adhesive composition includes a plasticizer, the adhesive strength of the pressure-sensitive adhesive composition after heat-UV curing may be lowered. Specifically, the plasticizer has a hydrophobic property (hydrophobic), it is possible to lower the surface adhesion with the adherend of the pressure-sensitive adhesive composition after heat-UV curing.

In one embodiment, the plasticizer is 50 parts by weight or less based on 100 parts by weight of the solid content of the (meth) acrylate resin containing the unsaturated group; Or 45 parts by weight or less. When the plasticizer is contained in an amount of more than 50 parts by weight, a bleeding out phenomenon may occur, and the adhesive strength after heat-UV curing of the adhesive composition may decrease.

This application is a base film; And a pressure-sensitive adhesive layer provided on the base film, wherein the pressure-sensitive adhesive layer includes (meth) acrylate resin; And it provides a surface protective film containing an unsaturated group.

In one embodiment, when the surface protective film provided with the pressure-sensitive adhesive layer containing the thermosetting of the pressure-sensitive adhesive composition is placed in a nuclear magnetic resonance spectroscopy analyzer, and the ¹ H NMR spectrum of the pressure-sensitive adhesive layer is measured at a frequency of 500 mHz, 4.5 ppm and The peak between 7ppm can be seen. In one embodiment, the ¹ H NMR spectrum of the pressure-sensitive adhesive layer is a value measured in a solid state.

In one embodiment, the surface protective film provided with the pressure-sensitive adhesive layer containing the heat-UV cured product of the pressure-sensitive adhesive composition was put in a nuclear magnetic resonance analyzer, and when measuring the ¹ H NMR spectrum of the pressure-sensitive adhesive layer at a frequency of 500 mHz, 4.5 It can be seen that the peak between ppm and 7 ppm disappeared.

In one embodiment, the nuclear magnetic resonance spectroscopy analysis may be performed using an AVANCE 500 (Bruker Co., Germany) device, but is not limited thereto.

As in the method for confirming the unsaturated group, ¹ H NMR spectrum of the pressure-sensitive adhesive layer can be measured to confirm that the pressure-sensitive adhesive layer contains an acrylate resin.

In one embodiment, the pressure-sensitive adhesive layer further includes a photoinitiator.

In one embodiment, the pressure-sensitive adhesive layer further includes a plasticizer.

In one embodiment, the composition of the pressure-sensitive adhesive layer and the content of each composition can be confirmed through analysis of a solid state using a nuclear magnetic resonance spectroscopy.

In the present specification, unless otherwise specified, the pressure-sensitive adhesive layer means a pressure-sensitive adhesive layer containing a thermoset of the above-mentioned pressure-sensitive adhesive composition.

In one embodiment, the surface protective film further includes a protective film provided on the opposite side of the surface of the pressure-sensitive adhesive layer provided with the base film.

The surface protection film according to an exemplary embodiment includes a base film 110 as illustrated in FIG. 1; Pressure-sensitive adhesive layer 120; And a protective film 130 may be sequentially stacked, and the pressure-sensitive adhesive layer 120 includes a thermoset of the above-described pressure-sensitive adhesive composition.

The method of forming the pressure-sensitive adhesive layer containing the heat cured product of the pressure-sensitive adhesive composition is not particularly limited. For example, the pressure-sensitive adhesive composition is coated on a base film by a conventional means such as a bar coater, then cured, or once peeled off the pressure-sensitive adhesive composition. After coating and curing the surface of the base material to form an adhesive layer, a method of transferring it back to the base film may be used.

In one embodiment, the method of manufacturing the surface protection film includes coating an adhesive composition on one surface of a base film; And curing the coated adhesive composition to form an adhesive layer.

In one embodiment, the method for manufacturing the surface protective film further includes laminating a protective film on one surface of the pressure sensitive adhesive layer after the pressure sensitive adhesive layer forming step.

The coating method of the pressure-sensitive adhesive composition may include a roll coating method such as reverse coating and gravure coating, a spin coating method, a screen coating method, a fountain coating method, a dipping method, and a spray method, but is not limited thereto.

In one embodiment, curing of the coated pressure-sensitive adhesive composition may be performed for 2 minutes to 5 minutes at a temperature of 100 ° C to 140 ° C in an oven.

The thickness of the pressure-sensitive adhesive layer is not limited, but in one embodiment, the thickness of the pressure-sensitive adhesive layer is 40 μm or less; 35 μm or less; 30 μm or less; Or 27 µm or less. In one embodiment, the thickness of the pressure-sensitive adhesive layer is 10㎛ or more; 15 μm or more; Or 20 µm or more.

In one embodiment, the modulus at 23 ° C of the pressure-sensitive adhesive layer is 800,000 Pa or less; 750,000 Pa or less; Or 700,000 Pa or less. When the modulus before curing of the above-described pressure-sensitive adhesive layer is within the above range, even steps of 40 μm or less can overcome the step difference between panels.

In one embodiment, the modulus at 23 ° C of the pressure-sensitive adhesive layer is 380,000 Pa or more; More than 400,000 Pa. When the modulus of the pressure-sensitive adhesive layer is less than the above range, steaming or the like may occur in the pressure-sensitive adhesive layer.

In one embodiment, the adhesive layer is attached to a glass plate with a 2 kg roller, Peeling force when peeling the surface protection film from the glass plate at a peeling rate of 1.8 m / min and a peeling angle of 180 ° is 10 gf / in or more; Or 12 gf / in or more.

In one embodiment, when the pressure-sensitive adhesive layer is attached to a glass plate and UV light of 300 mJ / cm ² is applied with an LED lamp having a wavelength of 365 nm, the surface protection film is peeled from the glass plate at a rate of 1.8 m / min and 180 ° The peeling force at the time of peeling at the peeling angle is 7 gf / in or less, and preferably 6 gf / in or less.

In one embodiment, when the pressure-sensitive adhesive layer is attached to a glass plate and 1,000 mJ / cm ² of ultraviolet light is applied with an LED lamp of 365 nm wavelength, the surface protection film is peeled at a rate of 1.8 m / min and 180 ° from the glass plate. Peeling force when peeling at a peeling angle of 4 gf / in or less; 3.5 gf / in or less; Or 3 gf / in or less.

In one embodiment, when the pressure-sensitive adhesive layer is attached to a glass plate and UV light of 2,000 mJ / cm ² is applied with an LED lamp having a wavelength of 365 nm, the surface protection film is peeled from the glass plate at a rate of 1.8 m / min and 180 ° Peeling force when peeling at a peeling angle of 4 gf / in or less; 3.5 gf / in or less; Or 3 gf / in or less.

In the present specification, the peeling force when peeling the surface protective film from the glass plate at a peeling rate of 1.8 m / min and a peeling angle of 180 ° is a value measured under conditions of 25 ° C. and 50% relative humidity.

In one embodiment, the residual adhesion rate of the pressure-sensitive adhesive layer is 80% or more; 85% or more; Or 90% or more.

The residual adhesion rate of the pressure-sensitive adhesive layer according to an exemplary embodiment of the present application may be calculated as A ₁ / A ₂ × 100.

The A ₁ adheres the pressure-sensitive adhesive layer to the glass plate, and after adding 2,000 mJ / cm ² of ultraviolet light, it is stored for 240 hours at 60 ° C. and 90% relative humidity, and the pressure-sensitive adhesive layer is 1.8 m / to the glass plate. Peeling at a peeling speed of min and a peeling angle of 180 °, an OCA (Optically Clear Adhesive) film (LGC, OC9052D) having a thickness of 50 μm is attached to the glass plate from which the adhesive layer has been peeled, and the OCA film is 0.3 from the glass plate. It means the peeling force when peeling at a peeling speed of m / min and a peeling angle of 180 °.

The A ₂ refers to the peeling force when the OCA (Optically Clear Adhesive) film (LGC, OC9052D) is peeled from the glass plate at a peel rate of 0.3 m / min and a peel angle of 180 °.

The present application is an organic light emitting device; And an adhesive layer provided on the organic light emitting element, wherein the adhesive layer comprises (meth) acrylate resin; And it provides an organic light emitting electronic device comprising an unsaturated group.

The present application is an organic light emitting device; And an adhesive layer provided on the organic light emitting device, wherein the adhesive layer includes a cured product of the adhesive composition.

In the present specification, 'curing' refers to a process in which the components included in the composition are converted into a state in which the composition can exhibit adhesive performance by chemical, physical action or chemical reaction.

In the present specification, the pressure-sensitive adhesive composition is a thermosetting pressure-sensitive adhesive composition and a photocurable pressure-sensitive adhesive composition.

In the present specification, thermosetting means that curing is induced by application of heat, and photocuring means that curing is induced by electromagnetic waves. Here, electromagnetic waves include microwaves, infrared rays (IR), ultraviolet rays (UV), X-rays, gamma rays, and particle beams.

In one embodiment, the organic light emitting electronic device comprises the steps of attaching the surface protective film on the encapsulation layer of the organic light emitting device such that the pressure-sensitive adhesive layer contacts the encapsulation layer; UV curing the pressure-sensitive adhesive layer; And it may be manufactured by a method of manufacturing an organic light emitting electronic device comprising the step of removing the surface protection film.

In one embodiment, when the surface protective film further includes a protective film, the method of manufacturing the organic light emitting electronic device may further include removing the protective film from the surface protective film.

The step of removing the protective film may be performed before the step of attaching the adhesive layer on the encapsulation layer.

In one embodiment, UV curing of the pressure-sensitive adhesive layer can be achieved by applying 300 mJ / cm ² or more of ultraviolet light with an LED lamp of 365 nm wavelength.

In one embodiment, the organic light emitting device sequentially includes a back plate, a plastic substrate, a thin film transistor, an organic light emitting diode, and an encapsulation layer.

As the encapsulation layer, a material that is usually used as an encapsulation layer of an organic light emitting device can be used. In one embodiment, the encapsulation layer is glass; Silicon nitride (SiN); Silicon oxide (SiO ₂ ), and the like, but is not limited thereto.

The types of the base film and the protective film are not particularly limited. The base film is, for example, polyethylene terephthalate film, polytetrafluoroethylene film, polyethylene film, polypropylene film, polybutene film, polybutadiene film, vinyl chloride copolymer film, polyurethane film, ethylene-vinyl acetate film , Ethylene-propylene copolymer film, ethylene-acrylic acid ethyl copolymer film, ethylene-acrylic acid methyl copolymer film or polyimide film may be used, but is not limited thereto. In one embodiment, the base film and the protective film may be polyethylene terephthalate (PET) film. The base film and the protective film may be composed of a single layer, or two or more layers may be laminated.

The thickness of the base film and the protective film may be appropriately selected in consideration of the purpose of the present application.

In one embodiment, the thickness of the base film may be 50 μm or more and 125 μm or less, or 60 μm or more and 100 μm or less.

In one embodiment, the protective film may be 25 μm or more and 75 μm or less, or 60 μm or more and 100 μm or less.

On the one side or both sides of the base film and the protective film, conventional physical or chemical surface treatments such as mat treatment, corona discharge treatment, primer treatment and crosslinking treatment are carried out in order to improve adhesion, retention, etc. with the adhesive layer or other layers. Can be.

The present specification is a step of removing the protective film from the surface protective film; And attaching the base film and the adhesive film on the encapsulation layer of the organic light emitting device such that the pressure sensitive adhesive layer contacts the encapsulation layer.

The present specification is a step of removing the protective film from the surface protective film; Attaching the base film and the pressure-sensitive adhesive layer on the sealing layer of the organic light emitting device such that the pressure-sensitive adhesive layer is in contact with the sealing layer; And it provides a method of manufacturing an organic light emitting electronic device comprising the step of removing the base film.

In one embodiment, the organic light emitting device sequentially includes a back plate, a plastic substrate, a thin film transistor, an organic light emitting diode, and an encapsulation layer. In one embodiment, the base film 110 and the pressure-sensitive adhesive layer 120 peeled from the surface protection film, the pressure-sensitive adhesive layer as shown in Figure 3 back plate 511, plastic substrate 512, thin film transistor 513, an organic light emitting diode 514, and an encapsulation layer 515 are attached to contact the surface of the encapsulation layer 515 of the organic light emitting device 510 sequentially stacked.

The present specification also provides a method of manufacturing an organic light emitting electronic device further comprising laminating a touch screen panel and a cover window on the encapsulation layer from which the cured adhesive layer is removed.

However, the use of the pressure-sensitive adhesive composition according to an exemplary embodiment of the present application is not limited to the protection of the encapsulation layer of the organic light emitting device, and may also be used to protect the surface of other optical devices.

For example, the above-described surface protection film may be used for protection of the touch panel, but is not limited thereto. The surface of the pressure-sensitive adhesive layer of the surface protection film including the pressure-sensitive adhesive layer is attached to the surface of the optical element, and accordingly, the optical element can be protected by the surface protection film.

Hereinafter, the present application will be described in more detail through examples according to the present application and comparative examples not according to the present application, but the scope of the present application is not limited by the examples presented below.

Example 1

<Production of Resin 1>

2-ethylhexyl acrylate (2-EHA) in a 1L reactor equipped with a cooling device so that nitrogen gas is refluxed and temperature control is easy. 47 middle part; 2-ethylhexyl methacrylate (2-EHMA) 27 parts by weight; 10 parts by weight of n-butyl acrylate; And 2-hydroxyethyl acrylate (2-HEA) was added to a monomer mixture composed of 16 parts by weight, and then 65 parts by weight of a solvent in which toluene and ethyl acetate (EAc) were mixed at a weight ratio of 50:50 was added. Then, nitrogen gas was purged for about 1 hour to remove oxygen, and then the reactor temperature was maintained at 80 ° C. After homogenizing the mixture, 0.3 parts by weight of azobisisobutyronitrile (AIBN) was added as a reaction initiator, and the mixture was reacted for 12 hours to prepare Resin 1-1. After the reaction, it was diluted with toluene and ethyl acetate.

Resin 1 was obtained by adding 18 parts by weight of 2-isocyanatoethyl methacrylate and 50 ppm of catalyst (DBTDL) to 100 parts by weight of the monomer mixture in the solvent and reacting for 8 hours. (OH value = 11.9 mgKOH / g, Mw = 550,000 g / mol)

<Preparation of adhesive composition 1>

100 parts by weight of the prepared resin 1; Isocyanate-based curing agent TDI (AK-75, Aekyung Chemical) 2.7 parts by weight; And 3 parts by weight of a photoinitiator (I-184, Ciba), ethyl acetate was added to a solid content concentration of 40 wt% and stirred with a disper to prepare a pressure-sensitive adhesive composition 1.

<Preparation of adhesive composition 2>

The pressure-sensitive adhesive composition 2 was prepared in the same manner as the manufacturing method of the pressure-sensitive adhesive composition 1, except that the resin composition further comprises 20 parts by weight of plasticizer (ATBC, Lemon chem) compared to 100 parts by weight of the resin 1.

<Preparation of adhesive composition 3>

The pressure-sensitive adhesive composition 2 was prepared in the same manner as the manufacturing method of the pressure-sensitive adhesive composition 1, except that the resin composition further comprises 40 parts by weight of plasticizer (ATBC, Lemon chem) compared to 100 parts by weight of the resin 1.

<Preparation of Comparative Composition 1>

Comparative composition 1 in the same manner as the manufacturing method of the pressure-sensitive adhesive composition 1, except that the resin composition further comprises 40 parts by weight of plasticizer (ATBC, Lemon chem) compared to 100 parts by weight of the resin 1, and the curing agent is not used Was prepared.

<Preparation of Comparative Composition 2>

Resin 2 (7760, Dow Corning) 98 parts by weight; And a curing agent (7028, Dow Corning) 2 parts by weight, ethyl acetate was added to a solid content concentration of 40 wt% and stirred with a disper to prepare an adhesive composition.

<Preparation of Comparative Composition 3>

Comparative composition 3 was prepared in the same manner as in the manufacturing method of the pressure-sensitive adhesive composition 1, except that the resin 1-1 was used instead of the resin 1.

Compositions of the pressure-sensitive adhesive compositions 1 to 3 and comparative compositions 1 to 3 are described in Table 1 below, and the physical properties of each composition are shown in Table 2 below.

How to measure hydroxyl value

Acetylation reagent: a solution of 70 g of phthalic anhydride and 500 g of pyridine mixed

Phenolphthalein indicator: A solution of 0.5 g of phenolphthalein stock solution, 250 g of ethanol and 250 g of distilled water

1 g of the resin to be measured was added to 25.5 g of an acetylation reagent, and stirred in an oil bath at 100 ° C. for 2 hours. After air cooling for 30 minutes, 10 ml of pyridine is added. Thereafter, 50 ml (51 g) of 0.5N KOH, 10 drops of a magnetic bar and a phenolphthalein indicator are added, and 0.5N KOH is titrated until the solution turns pink while stirring on a plate.

The hydroxyl value was calculated by the following equation.

Hydroxyl value = 28.05 × (A-B) × F / (sample volume)

A: 0.5N KOH (ml) required for blanking

B: 0.5N KOH (ml) required for this test

F: The amount of KOH when titrated with 0.5N KOH (ml) after adding 10 drops of magnetic bar and phenolphthalein indicator to 10 ml of 1N HCL

Preparation of surface protection film

A 75 µm thick polyethylene terephthalate (PET) film (AFV, SKC-HMT) was prepared as the base film. As a protective film, a polyethylene terephthalate (PET) film (RF12ASW, SKC-HMT) having a thickness of 50 μm was prepared.

Next, a pressure-sensitive adhesive composition was comma-coated to a thickness of 25 μm on one side of the base film and dried for 4 minutes at a temperature of 110 ° C., and then a protective film was laminated on the pressure-sensitive adhesive layer to prepare a surface protective film.

Measurement of adhesive strength (adhesive force A) of the adhesive layer before curing

After removing the protective film from the surface protective film, the pressure-sensitive adhesive layer is attached to a glass plate (NEG, OA-21) with a 2 kg roller. Then, the peeling force when peeling the adhesive layer at a peeling rate of 1.8 m / min and a peeling angle of 180 ° was measured using a Texture Analyzer (manufactured by Stable Micro Systems, UK). The peeling force at this time was described as adhesive force A.

Measurement of adhesive strength of the adhesive layer after curing

After removing the protective film from the surface protective film, it is attached to a glass plate (NEG, OA-21). Thereafter, 300 mJ / cm ² of ultraviolet light is applied to cure the pressure-sensitive adhesive layer.

Peeling force B1 when peeling the cured pressure-sensitive adhesive layer at a peeling rate of 1.8 m / min and a peeling angle of 180 ° was measured using a Texture Analyzer (manufactured by Stable Micro Systems, UK).

Peeling force B2 is the peeling force of varying the irradiation energy at the time of curing of the pressure-sensitive adhesive layer to 1,000 mJ / cm ² , and peeling force B3 is the peeling force of varying the irradiation energy at the time of curing to 2,000 mJ / cm ² .

Measurement of residual adhesion rate

The residual adhesion rate of the pressure-sensitive adhesive layer was calculated as A ₁ / A ₂ × 100.

<Measurement of A ₁ >

The adhesive layer was attached to a glass plate (NEG, OA-21) using a 2 kg roller, and stored at 240 ° C. and 90% relative humidity for 240 hours after adding 2,000 mJ / cm ² of ultraviolet light. The adhesive layer was peeled at a peeling rate of 1.8 m / min and a peeling angle of 180 ° with respect to the glass plate, and an optically clear adhesive (OCA) film (LGC, OC9052D) having a thickness of 50 μm was applied to the peeled glass plate. Attached. The peeling force when the OCA film was peeled with respect to the glass plate at a peeling rate of 0.3 m / min and a peeling angle of 180 ° was measured, and this was set as the adhesive force A ₁ .

<Measurement of A ₂ >

OCA (Optically Clear Adhesive) film (LGC, OC9052D) was measured from the glass plate (NEG, OA-21) at a peeling rate of 0.3 m / min and a peeling angle of 180 °, and the peeling force was measured. _{Let 2} be.

Modulus measurement

After cutting the surface protection film to a size of 1 cm × 1 cm, using a dynamic rheology meter (ARES, RDA, TA Instruments Inc.), 23 ° C. while applying shear stress between parallel plates at a frequency of 1 Hz. The modulus at was measured.

Suzy Hardener Photoinitiator Plasticizer (% by weight) Example 1 Resin 1 AK-75 I-184 - Example 2 Resin 1 AK-75 I-184 (Kind) (20wt%) Example 3 Resin 1 AK-75 I-184 (Kind) (40wt%) Comparative Example 1 Resin 1 - I-184 (Kind) (40wt%) Comparative Example 2 Resin 2 7028 - - Comparative Example 3 Resin 3 AK-75 I-184 (Kind) (40wt%)

Adhesion A
(gf / in) Adhesion B1
(gf / in) Adhesion B2
(gf / in) Adhesion B3
(gf / in) Residual adhesion rate
(gf / in) Modulus
(Pa) Example 1 107.6 40.7 12.8 57.8 94% 671,226 Example 2 40.7 3.7 2.6 2.0 91% 576,122 Example 3 12.8 2.3 1.3 1.6 93% 461,361 Comparative Example 1 57.8 5.6 2.2 1.5 64% 311,231 Comparative Example 2 2.5 2.8 3.1 2.6 27% 971,345 Comparative Example 3 10.8 12.3 12.3 14.5 68% 321,453

From Table 2, it can be seen that the pressure-sensitive adhesive layer formed using the pressure-sensitive adhesive composition of the present invention has a lower adhesive strength after UV curing than before UV curing.

In addition, it can be seen that the pressure-sensitive adhesive layer containing the thermosetting of the pressure-sensitive adhesive composition of the present invention has low modulus, and the pressure-sensitive adhesive layer containing the heat-UV cured product of the pressure-sensitive adhesive composition of the present invention has little residue on the surface of the pressure-sensitive adhesive. have.

110: base film
120: adhesive layer
130: protective film
510: organic light emitting device
511: back plate film
512: plastic substrate
513: thin film transistor
514: organic light emitting diode
515: Encapsulation Layer

Claims (21)

(Meth) acrylate resin containing an unsaturated group; Photoinitiators; And an isocyanate-based curing agent. The method according to claim 1, If the number of moles of the hydroxy group contained in the (meth) acrylate resin containing the unsaturated group is n ₁ , and the number of moles of the isocyanate group contained in the isocyanate curing agent is n ₂ , n ₂ / The pressure-sensitive adhesive composition of n ₁ (NCO / OH) is 1 to 3.5. The method according to claim 1, wherein the hydroxyl value of the (meth) acrylate resin containing the unsaturated group is 7mgKOH / g to 15mgKOH / g pressure-sensitive adhesive composition. The method according to claim 1, The (meth) acrylate resin containing the unsaturated group is a unit derived from (meth) acrylate containing a hydroxyl group; And a unit derived from (meth) acrylate containing an unsaturated group. The method according to claim 1, (meth) acrylate resin containing the unsaturated group is a unit derived from an alkyl (meth) acrylate; Unit derived from (meth) acrylate containing a hydroxy group; And a random polymer composed of units derived from (meth) acrylate containing an unsaturated group. The method according to claim 5,
The unit derived from the alkyl (meth) acrylate is included in 60 to 89 mol% compared to the total monomer units included in the (meth) acrylate resin containing the unsaturated group,
The unit derived from the (meth) acrylate containing the hydroxy group is included in 1 mol% to 10 mol% compared to the total monomer units included in the (meth) acrylate resin containing the unsaturated group,
The unit derived from the (meth) acrylate containing the unsaturated group is an adhesive composition comprising 10 to 30 mol% compared to the total monomer units included in the (meth) acrylate resin containing the unsaturated group. The method according to claim 4, The unit derived from the (meth) acrylate containing the unsaturated group is a pressure-sensitive adhesive composition that is a unit represented by the formula (2):
[Formula 2]

In Chemical Formula 2,

Is a site connecting with other monomer units included in the (meth) acrylate resin containing the unsaturated group,
R ₁ is hydrogen; Or a methyl group,
R ₂ is hydrogen; Or a methyl group,
L ₁ is a straight chain or branched alkylene group,
L ₂ is a straight-chain or branched alkylene group. The method according to claim 1, wherein the isocyanate-based curing agent is 2,4- or 4,4'-methylene diphenyl diisocyanate (MDI), xylylene diisocyanate (XDI), m- or p-tetramethylxylylene diisocyanate (TMXDI ), Toluylene diisocyanate (TDI), di- or tetra-alkyldiphenylmethane diisocyanate, 3,3'-dimethyldiphenyl-4,4'-diisocyanate (TODI), 1,3-phenylene diisocyanate , 1,4-phenylene diisocyanate, naphthalene diisocyanate (NDI), 4,4'-dibenzyldiisocyanate, hydrogenated MDI (H ₁₂ MDI), 1-methyl-2,4-diisocyanatocyclohexane, 1 , 12-diisocyanatododecane, 1,6-diisocyanato-2,2,4-trimethylhexane, 1,6-diisocyanato-2,4,4-trimethylhexane, isophorone diisocyanate (IPDI) , Tetramethoxybutane-1,4-diisocyanate, butane-1,4-diisocyanate, hexane-1,6-diisocyanate (HDI), A pressure-sensitive adhesive composition material fatty acid diisocyanate, dicyclohexyl methane diisocyanate, cyclohexane-1,4-diisocyanate, and ethylene diisocyanate is at least one or two selected from the group consisting of. The method according to claim 1, wherein the photoinitiator is composed of a triazine-based compound, a biimidazole compound, an acetophenone-based compound, an O-acyloxime-based compound, a thioxanthone-based compound, a phosphine oxide-based compound, a coumarin-based compound, and a benzophenone-based compound. The pressure-sensitive adhesive composition is one or two or more selected from the group. The method according to claim 1, The pressure-sensitive adhesive composition further comprises a plasticizer. Base film; And a pressure-sensitive adhesive layer provided on the base film, wherein the pressure-sensitive adhesive layer includes (meth) acrylate resin; And an unsaturated group. The surface protective film of claim 11, wherein the pressure-sensitive adhesive layer has a thickness of 40 μm or less. The method according to claim 11, when the pressure-sensitive adhesive layer is attached to the glass plate, the peeling force when peeling the surface protection film from the glass plate at a peeling rate of 1.8 m / min and a peeling angle of 180 ° is 10gf / in or more surface Protective film. The method according to claim 11, When the pressure-sensitive adhesive layer is attached to the glass plate, and when applying a UV of 300mJ / cm ² with a LED lamp of 365nm wavelength, the surface protection film from the glass plate at a peel rate of 1.8m / min and 180 ° peel The peeling force at the time of peeling at an angle is 7 gf / in or less. The method according to claim 11, When the pressure-sensitive adhesive layer is attached to the glass plate, when applying a UV light of 1,000mJ / cm ² with a LED lamp of 365nm wavelength, the surface protection film from the glass plate of 1.8m / min peel rate and 180 ° The peeling force when peeling at a peeling angle is 5 gf / in or less. The method according to claim 11, When the pressure-sensitive adhesive layer is attached to the glass plate, and when applying an ultraviolet ray of 2,000mJ / cm ² with an LED lamp of 365nm wavelength, the surface protective film is peeled from the glass plate at a rate of 1.8m / min and 180 ° The peeling force at the time of peeling at the peeling angle is 4 gf / in or less. The method according to claim 11, When the pressure-sensitive adhesive layer is attached to the glass plate, the peeling force when peeling the surface protection film from the glass plate at a peeling rate of 1.8 m / min and a peel angle of 180 ° is 10gf / in or more,
When the pressure-sensitive adhesive layer is attached to a glass plate and 2,000 mJ / cm ² of ultraviolet light is applied with an LED lamp of 365 nm wavelength, the surface protection film is peeled from the glass plate at a peeling rate of 1.8 m / min and a peeling angle of 180 °. The peeling force at the time is a surface protection film which is 7 gf / in or less. The surface protection film of claim 11, further comprising a protective film provided on a surface opposite to the surface of the pressure-sensitive adhesive layer on which the base film is provided. Organic light emitting devices; And an adhesive layer provided on the organic light emitting element, wherein the adhesive layer comprises (meth) acrylate resin; And an unsaturated group. The organic light emitting electronic device of claim 19, wherein the organic light emitting device sequentially comprises a back plate, a plastic substrate, a thin film transistor, an organic light emitting diode, and an encapsulation layer. Attaching the surface protection film according to claim 11 on an encapsulation layer of an organic light emitting device such that the pressure-sensitive adhesive layer makes contact with the encapsulation layer; UV curing the pressure-sensitive adhesive layer; And removing the surface protective film.

Images