KR20180021582A - Pressure-sensitive adhesive composition - Google Patents

Abstract

The present application provides an adhesive agent composition capable of effectively blocking water or oxygen introduced from the outside into an organic electronic device and capable of realizing not only durability and reliability under extreme conditions such as high temperature and high humidity but also excellent optical characteristics and an adhesive film comprising the same. The adhesive agent composition of the present invention comprises: an olefin-based compound as a polymerization unit; a base resin containing at least one reactive functional group; and a curing compound having a bicyclic structure in a molecular structure.

Description

[0001] PRESSURE-SENSITIVE ADHESIVE COMPOSITION [0002]

The present application relates to a pressure-sensitive adhesive composition, an adhesive film comprising the same, and an organic electronic device including the same.

An organic electronic device (OED) refers to an apparatus that includes an organic material layer that generates holes and electrons to generate an alternating current. Examples thereof include a photovoltaic device, a rectifier, A transmitter and an organic light emitting diode (OLED).

Organic light emitting diodes (OLEDs) among the organic electronic devices have lower power consumption, faster response speed, and are advantageous for thinning display devices or illumination. In addition, OLEDs are expected to be applied in various fields covering various portable devices, monitors, notebooks, and televisions because of their excellent space utilization.

In commercialization of OLEDs and expansion of applications, the main problem is durability. Organic materials and metal electrodes contained in OLEDs are very easily oxidized by external factors such as moisture. Thus, products containing OLEDs are highly sensitive to environmental factors. Accordingly, various methods have been proposed to effectively block penetration of oxygen or moisture from the outside into organic electronic devices such as OLEDs.

In recent years, attempts have been made to use a PIB (polyisobutylene) resin as a pressure-sensitive adhesive composition for sealing. PIB (polyisobutylene) resin is superior to acrylic resin in blocking ability to prevent the influence of moisture and active oxygen, and is transparent and has almost no effect of corrosion. However, it causes problems such as restriction of the hardener content due to compatibility problems and consequent reduction of the water barrier effect due to the problem of lowering the crosslink density.

Patent Document 1 is a film of an adhesive encapsulating composition and an organic electroluminescent device, which is an adhesive based on PIB (polyisobutylene) and has poor processability and poor reliability under high temperature and high humidity conditions.

Therefore, it is required to develop an encapsulant that can maintain the reliability at high temperature and high humidity conditions and has excellent optical characteristics, while securing the required lifetime in the organic electronic device and effectively blocking the penetration of moisture.

Korean Patent Publication No. 2008-0088606

The present application provides a pressure-sensitive adhesive composition which is capable of effectively blocking moisture or oxygen introduced from the outside into an organic electronic device, excellent in heat resistance, chemical resistance and transparency, and an adhesive film containing the same.

The present application relates to a pressure-sensitive adhesive composition. The pressure-sensitive adhesive composition can be applied to encapsulating or encapsulating organic electronic devices such as, for example, OLEDs. For example, the pressure-sensitive adhesive composition may be applied to encapsulate the front surface of an organic electronic device, or may be applied to a surface of the substrate on which the device is formed, to be located on the opposite side of the surface on which the device is formed.

In the present application, the term " organic electronic device " means an article or apparatus having a structure including an organic material layer that generates alternating electric charges using holes and electrons between a pair of electrodes facing each other, But are not limited to, photovoltaic devices, rectifiers, transmitters, and organic light emitting diodes (OLEDs). In one example of the present invention, the organic electronic device may be an OLED.

Exemplary pressure sensitive adhesive compositions may include a base resin. Further, the pressure-sensitive adhesive composition may further comprise a curable compound. The base resin may include an olefin-based compound as a polymerization unit, and may include at least one reactive functional group. In addition, the curable compound may have a lysine structure in a molecular structure. Since the curable compound has an iridium structure, the compatibility of the base resin with the curable compound is increased, and thus the water barrier property can be improved, and the heat resistance, durability and optical properties at high temperature and high humidity can be maintained at the same time .

The term " bicyclic compound " in the present application may mean a bonding structure or a bridged ring structure in which two rings are bonded to one compound.

In one example, the curable compound may be a polymer derived from a cyclic olefin monomer having at least one or more < RTI ID = 0.0 > The cyclic olefin monomer may be at least one selected from norbornene-based olefins, tetracyclododecene-based olefins, dicyclopentadiene-based olefins, and derivatives thereof. The derivatives are those wherein the basic olefin structure is at least one selected from the group consisting of alkyl, alkylidene, aralkyl, cycloalkyl, ether, acetyl, aromatic, ester, hydroxy, alkoxy, cyano, amide, imide, Or a structure containing a substituent.

In one embodiment of the present application, the curable compound may include at least one curable functional group. The curable functional group may be at least one selected from, for example, a glycidyl group, an isocyanate group, a hydroxyl group, a carboxyl group, an amide group, an epoxide group, a cyclic ether group, a sulfide group, an acetal group and a lactone group.

Specifically, the curable functional group may be an epoxide group, and the epoxide group may be an epoxidized form of the unsaturated group present in the curable compound. The unsaturated group may be, for example, a carbon-carbon double bond. In one example, the epoxidation may refer to a reaction in which one atom of oxygen is added to the ethylene bond to produce the 1,2-epoxide.

In one embodiment, the epoxidation can be carried out using an oxidizing agent. The oxidizing agent may be a known oxidizing agent that can be epoxidized, and may include, for example, organic peroxides such as hydrogen peroxide, per formic acid, peracetic acid, trifluoroacetic acid, perbenzoic acid, m- chlorobenzoic acid (mCPBA), dimethyldioxirane; Oxo complexes such as salen complexes; Peroxydic acid salts such as magnesium monoperoxyphthalate, oxone and the like can be used. Specifically, peroxide salts can be used from the viewpoint of the reaction efficiency. The present application can introduce an epoxy group into an unsaturated group even at a low acidity when the curable compound is epoxidized using a peroxide salt, thereby minimizing the problem of forming a hydroxyl group through side reactions that may occur at high acidity.

In embodiments of the present application, the curable compound may have a cyclic structure in which the ring constituent atoms within the molecular structure are in the range of 5 to 20, 5 to 15, or 5 to 10. Further, the curable compound may have the cyclic structure even after the pressure-sensitive adhesive is cured. The annular structure may be the above-described lyotropic structure. Since the pressure-sensitive adhesive composition of the present application contains the curable compound having the above structure, it can realize a stable cross-linking structure to external factors such as shrinkage and swelling even after crosslinking or curing when embodied with a pressure-sensitive adhesive.

In one example, the curable compound may be a compound represented by the following formula (1).

In Formula 1, R ₁ represents hydrogen or an alkyl group.

In another example, the curable compound may be a compound represented by the following formula (2).

In the above formula (2), R ₂ represents hydrogen or an alkyl group.

The term "alkyl group" in the present application may mean an alkyl group having 1 to 20 carbon atoms, 1 to 16 carbon atoms, 1 to 12 carbon atoms, 1 to 8 carbon atoms or 1 to 4 carbon atoms unless otherwise specified. The alkyl group may have a linear, branched or cyclic structure. In addition, the alkyl group may be optionally substituted by one or more substituents. Examples of the optionally substituted substituent include an alkyl group, an alkoxy group, an alkenyl group, an epoxy group, a cyano group, a carboxyl group, an acryloyl group, a methacryloyl group, an acryloyloxy group, a methacryloyloxy group or an aryl group And the like, but the present invention is not limited thereto. In particular, when the curable compound according to the present invention is the compound of the above formula (2), the crosslinking structure and degree of crosslinking in an appropriate range can be ensured without using a separate tackifier, and the compatibility of the tackifier The problem that the optical characteristics are lowered can be prevented.

In one example, the curable compound may be included in an amount of 5 to 80 parts by weight, 5 to 75 parts by weight, 5 to 70 parts by weight, or 5 to 65 parts by weight based on 100 parts by weight of the base resin. Within the above-mentioned weight range, the present application can be applied to encapsulating an organic electronic device to realize an endurance reliability at high temperature and high humidity together with excellent moisture barrier properties.

In one embodiment of the present application, the base resin may have an acid to water ratio (R) of 10% or less, 5% or less, or 1% or less.

[Formula 1]

R = H / (E + H) x 100

In the general formula (1), E represents the integration of peaks due to the reactive functional groups in ¹ H-NMR, and H represents the integration of peaks attributable to hydroxyl groups.

The lower limit of the hydroxyl group area ratio (R) may be 0%. The measurement method of ¹ H-NMR is not particularly limited and can be carried out in a known manner. For example, when the peaks derived from the respective reactive functional groups and the hydroxyl groups do not overlap with each other, they can be obtained through the area of the peak, and when the peaks overlap each other, the ratio can be obtained in consideration of the overlapping portion have. Analysis programs capable of analyzing ¹ H-NMR spectrum and obtaining the area of a peak are variously known. For example, the area of a peak can be calculated using the MestReC program.

In one example, the base resin may be a homopolymer derived from an olefinic compound or a copolymer in which other polymerizable monomers are polymerized together. The application of the present application improves the compatibility of the base resin with the curing compound by introducing the reactive functional group into the desired range by controlling the area ratio of the hydroxyl group of the base resin to the above range, It is possible to maintain excellent heat resistance, durability reliability and optical characteristics at the same time at high temperature and high humidity.

In addition, the polymer may have at least one reactive functional group. The reactive functional group is not particularly limited as long as it is a functional group capable of reacting with the above-mentioned curable functional group. For example, the reactive functional groups may be in the form of epoxidized unsaturated groups of the base resin. Specifically, the reactive functional group may be an epoxidized form of the unsaturated group in the main chain of the base resin, and the epoxidation may proceed in the same manner as the epoxidation of the curable compound described above. In another embodiment, the reactive functional group may be in the form of an epoxidized unsaturated group of the side chain bonded organic group of the base resin. The side chain-bonded organic group may have a cyclic structure having 3 to 20 carbon atoms, 4 to 15 carbon atoms, or 5 to 12 carbon atoms. This application discloses that by using a base resin having a reactive functional group together with a curable compound, it is possible to increase the compatibility of the two resins, thereby realizing superior heat resistance, durability and optical characteristics at high temperature and high humidity .

In embodiments of the present application, the base resin comprises a resin derived from a mixture of monomers, and the mixture may comprise olefinic compounds. The olefin-based compound may have an isoolefin monomer component or a multi-olefin monomer component having at least 4 to 7 carbon atoms. The isoolefin may be present, for example, in the range of from 70 to 100 wt%, or from 85 to 99.5 wt%, based on the total monomer weight. The multi-olefin-derived component may be present in the range of 0.5 to 30 wt%, 0.5 to 15 wt%, or 0.5 to 8 wt%.

The isoolefin is, for example, an aromatic hydrocarbon such as isobutylene, 2-methyl-1-butene, 3-methyl-1-butene, , Vinyltrimethylsilane, hexene, or 4-methyl-1-pentene. The multi-olefins may have from 4 to 14 carbon atoms and include, for example, isoprene, butadiene, 2,3-dimethyl-1,3-butadiene, myrcene, 6,6-dimethyl-fulvene, hexadiene, cyclopentadiene, or Piperylene may be exemplified. Other polymerizable monomers such as styrene and dichlorostyrene can also be homopolymerized or copolymerized.

The base resin in the present application may comprise an olefinic compound homopolymer or copolymer. As mentioned above, the isobutylene-based olefin-based resin or polymer may mean an olefin-based resin or polymer containing 70 mol% or more of repeating units from isobutylene or isoprene and at least one other polymerizable unit.

In the present application, the base resin may be a butyl rubber or a branched butyl rubber. Exemplary base resins are unsaturated butyl rubbers such as olefins or copolymers of isoolefins and multi olefins. Examples of the base resin to be contained in the pressure-sensitive adhesive composition of the present invention include styrene-isoprene-styrene copolymer, poly (isobutylene-co-isoprene), polyisoprene, polybutadiene, polyisobutylene, Natural rubbers, butyl rubbers, and mixtures thereof.

In one example, the base resin may include a polymer having a reactive functional group side-bonded by grafting a compound having a polymerizable functional group to a polymer derived from an olefin-based compound. As the polymerizable functional group, for example, a carbon-carbon double bond, an acryloyl group or a methacryloyl group can be exemplified. Specifically, the reactive functional group may be an epoxy group, and specifically, the unsaturated group of the base resin may be an epoxidized epoxy group. As described above, the epoxidation can be carried out using an oxidizing agent.

In one example, the epoxy conversion of the unsaturated group of the base resin may be at least 70 mole%. The higher the epoxy conversion, the more dense crosslinking densities can be formed with the curable compound, thereby increasing the internal stress and providing a highly reliable encapsulant. From this viewpoint, the upper limit of the epoxy conversion is not particularly limited, and may be, for example, 99 mol% or less, 95 mol% or less, and 90 mol% or less.

In another example, the base resin may have an epoxy equivalent of from 100 g / eq to 20,000 g / eq. As described above, the base resin may contain a reactive functional group, and when the reactive functional group is an epoxy group, the epoxy equivalent may be controlled within the above range. By controlling the epoxy equivalent of the base resin within the above range, the present application provides a highly reliable sealing material by maintaining compatibility with a curable compound and forming a dense crosslinked density, increasing internal stress and realizing excellent transparency.

In one example, in the present application, the base resin may have a number average molecular weight such that the pressure-sensitive adhesive composition can be formed into a film shape. For example, the base resin may have a number average molecular weight of about 100,000 to 1,000,000, more than 100,000 to less than 900,000, about 150,000 to 800,000, about 200,000 to 700,000, or about 200,000 to about 650,000. By controlling the number average molecular weight of the base resin in the above range, the present application can maintain excellent heat resistance, endurance reliability and optical characteristics at high temperature and high humidity simultaneously after being applied as an encapsulating material.

The pressure-sensitive adhesive composition of the present application may further include a second curable compound having a molecular structure different from that of the above-mentioned curable compound, specifically, an alicyclic epoxy compound or a curable oligomer containing at least one cyclic ether group .

Examples of alicyclic epoxy compounds include 3,4-epoxycyclohexylmethyl 3 ', 4'-epoxycyclohexanecarboxylate (EEC) and derivatives, dicyclopentadiene dioxide and derivatives, vinylcyclohexyldioxide and derivatives, 1, 4-cyclohexanedimethanol bis (3,4-epoxycyclohexanecarboxylate) and derivatives, but are not limited thereto.

The curable oligomer may have a weight average molecular weight ranging from 1,000 to 100,000, from 2,000 to 90,000, from 3,000 to 80,000, from 4,000 to 70,000, or from 5,000 to 60,000. Within the above-mentioned molecular weight range, the pressure-sensitive adhesive composition of the present application is cured to have excellent water barrier properties, and excellent heat resistance and adhesiveness can be realized.

Examples of the curable oligomer include commercially available products such as EHPE3150, GT401, PB3600, and PB4700 manufactured by DAICEL. Also included are ether group-containing monomers such as M100 (7-oxabicyclo [4.1.0] heptan-3-yl) methyl methacrylate) or celloxide 2000 (4-vinyl-1-cyclohexene 1,2- Cationically-curable oligomers prepared by radical polymerization or the like using an ether group-containing monomer having a cyclic structure.

The second curable compound may be contained in an amount of 1 to 50 parts by weight, 5 to 40 parts by weight, 5 to 30 parts by weight, or 5 to 25 parts by weight based on 100 parts by weight of the base resin. Within the above-mentioned weight range, the present application can be applied to encapsulating an organic electronic device to realize an endurance reliability at high temperature and high humidity together with excellent moisture barrier properties.

In one embodiment, when the first curable compound of the present application is used in combination with the second curable compound, the first curable compound is used in an amount of 5 to 40 parts by weight, 5 to 30 parts by weight, or 5 to 30 parts by weight, 25 parts by weight. The first curable compound of the present application is applied to encapsulating the organic electronic device together with the second curable compound within the above-mentioned weight range, thereby realizing endurance reliability at high temperature and high humidity together with excellent moisture barrier.

The term " first curable compound " in the present application means a curable compound having the above-described lyotropic structure.

In one example, the pressure sensitive adhesive composition of the present application may further comprise a tackifier. The tackifier may be a resin produced by reacting a terpene compound with an aromatic compound. When the tackifier has an aromatic group in the molecular structure, compatibility between the above-mentioned base resin having a low polarity and a curing compound having a high polarity can be improved. The aromatic compound may include a reactive functional group. Examples of the functional group include a hydroxyl group, a carboxyl group, and an amine group. In the present application, the cross-linking density of the whole pressure-sensitive adhesive can be improved due to the reactive functional group. Specifically, the aromatic compound may be phenol, and the tackifier may be a terpene phenolic resin. The present application provides a pressure-sensitive adhesive excellent in adhesive strength as well as superior compatibility with a base resin and a curable compound by using the terpene phenolic resin as the tackifier, thereby improving crosslink density and durability .

The tackifier may be a resin produced by reacting a terpene compound with a phenolic compound. Terpene compound may represent a compound having a basic skeleton n (C ₅ H ₈₎ is 2 or more isoprene (C ₅ H ₈₎ combination. In the above, n may be two or more. In the above, the terpene compound may be at least one selected from the group consisting of? -Pinene,? -Pinene,? -Carenylene, 3-carene, D-limonene and dipentene. The phenolic compound may also be selected from the group consisting of phenol, para-tert-butylphenol (PTBP), 4-t-octylphenol (PTOP), 4- -pentyl phenol (PNPP), and para-n-hexyl phenol (PNHP).

The tackifier may be included in an amount of 10 to 100 parts by weight, 20 to 90 parts by weight, 30 to 90 parts by weight, 30 to 80 parts by weight or 35 to 70 parts by weight based on 100 parts by weight of the base resin. Within the above weight range, the tackifier can excellently realize compatibility of the base resin with the curable compound.

In the embodiment of the present application, the pressure-sensitive adhesive composition may further include a curing agent or an initiator depending on the kind of the base resin and the curable compound. For example, a curing agent capable of reacting with the base resin and the curable compound described above to form a crosslinked structure or the like or a cationic initiator capable of initiating a curing reaction may be further included. As the cationic initiator, a cationic photopolymerization initiator or a cationic thermal initiator may be used.

As the curing agent, there can be used one or more kinds of epoxy curing agents known in the art, such as amine curing agents, imidazole curing agents, phenol curing agents, phosphorus curing agents and acid anhydride curing agents, but not limited thereto .

In one example, as the curing agent, an imidazole compound which is solid at room temperature and has a melting point or a decomposition temperature of 80 ° C or higher can be used. Such compounds include, for example, 2-methylimidazole, 2-heptadecylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole or 1-cyanoethyl- For example, but not limited to,

The content of the curing agent may be selected depending on the composition of the composition, for example, the type and ratio of the base resin and the curable compound. For example, the curing agent may be contained in an amount of 1 part by weight to 20 parts by weight, 1 part by weight to 10 parts by weight, or 1 part by weight to 5 parts by weight based on 100 parts by weight of the curable compound. However, the weight ratio may be changed depending on the type and ratio of the functional group of the base resin and the curable compound or the compound, the crosslinking density to be implemented, and the like.

In one example, when the curable compound is a resin that can be cured by irradiation with an active energy ray, for example, a cationic photopolymerization initiator may be used as the initiator.

As the cationic photopolymerization initiator, an ionized cationic initiator or an organic silane or latent sulfonic acid series based onium salt or organometallic salt series or a nonionic ionic cationic photopolymerization initiator can be used. As the initiator of the onium salt series, diaryliodonium salt, triarylsulfonium salt or aryldiazonium salt can be exemplified, and the initiation of the organometallic salt series Examples of the initiator of the organosilane series include o-nitrobenzyl triaryl silyl ether, triaryl silyl peroxide, and the like. Or an acyl silane, and examples of the initiator of the latent sulfuric acid series include, but are not limited to,? -Sulfonyloxy ketone or? -Hydroxymethylbenzoin sulfonate, and the like .

In one example, an ionized cationic photopolymerization initiator may be used as the cationic initiator.

In one example, the initiator may be included in an amount of 0.1 to 10 parts by weight, 0.1 to 7 parts by weight, or 0.1 to 6 parts by weight based on 100 parts by weight of the base resin.

In the present application, unless otherwise specified, the unit " parts by weight " means a weight ratio between the respective components.

The pressure-sensitive adhesive composition according to the present application may contain various additives in addition to the above-mentioned composition, in addition to the effects of the above-mentioned invention, depending on the application, the kind of the resin component and the process for producing the pressure-sensitive adhesive layer described later. For example, the pressure-sensitive adhesive composition may be contained in an appropriate range depending on the intended properties of a moisture adsorbent, an inorganic filler, a coupling agent, a crosslinking agent, a curing substance, a UV stabilizer or an antioxidant.

In one example, the pressure sensitive adhesive composition according to the present application may have a gel content of 20% or more according to the following general formula (2).

[Formula 2]

Gel content (% by weight) = B / A x 100

In the general formula 2, A represents the mass of the pressure-sensitive adhesive composition, and B represents the mass of the pressure-sensitive adhesive composition. The pressure-sensitive adhesive composition is immersed in toluene at 25 ° C for 24 hours, filtered through a mesh of 200 mesh (pore size 74 μm) The dry mass of the insoluble component of the pressure-sensitive adhesive composition.

The gel content represented by the general formula 2 may be 20% to 95%, 25% to 90%, 35% to 85%, or 40% to 80%. That is, the present invention can provide a pressure-sensitive adhesive having excellent cross-linking structure and degree of crosslinking by controlling the gel content within the above range.

The pressure-sensitive adhesive composition according to the present application may satisfy the following general formula (3).

[Formula 3]

DELTA X ≤

In the general formula (1), DELTA X is a cross-linked product of the pressure-sensitive adhesive composition formed of a pressure-sensitive adhesive layer having a thickness of 30 mu m, and a substrate film having the pressure-sensitive adhesive layer formed on one surface thereof is attached to a glass plate with an adhesion area of 1 cm x 1 cm, , And then a pushing load of 1.5 kg at 25 캜 for 1000 seconds. The pushing distance represented by the general formula 3 may be 1000 占 퐉 or less, 10 to 990 占 퐉, 100 to 950 占 퐉, 200 to 950 占 퐉, or 500 to 930 占 퐉. That is, the present application secures an appropriate range of crosslinking structure and degree of crosslinking, thereby controlling the pushing distance to 1000 占 퐉 or less. In particular, when the adhesive film is applied to an organic electronic device, excellent moisture barrier properties, And optical characteristics.

The present application also relates to an adhesive film. The pressure-sensitive adhesive film may include a pressure-sensitive adhesive layer containing the pressure-sensitive adhesive composition described above. The structure of the pressure-sensitive adhesive film of the present application is not particularly limited, but may be, for example, a base film or a release film (hereinafter sometimes referred to as " first film "); And a pressure-sensitive adhesive layer formed on the base film or the release film.

The pressure-sensitive adhesive film of the present application may further include a base film or a release film (hereinafter sometimes referred to as " second film ") formed on the pressure-sensitive adhesive layer.

The specific kind of the first film that can be used in the present application is not particularly limited. In the present application, for example, a general polymer film in this field can be used as the first film. In the present application, for example, the base material or the release film may be a polyethylene terephthalate film, a polytetrafluoroethylene film, a polyethylene film, a polypropylene film, a polybutene film, a polybutadiene film, a polyvinyl chloride film, , An ethylene-vinyl acetate film, an ethylene-propylene copolymer film, an ethylene-ethyl acrylate copolymer film, an ethylene-methyl acrylate copolymer film, or a polyimide film. In addition, a suitable mold release treatment may be performed on one or both surfaces of the base film or release film of the present application. Examples of the releasing agent used in the releasing treatment of the base film include an alkyd type, a silicone type, a fluorine type, an unsaturated ester type, a polyolefin type, a wax type and the like. Among them, the use of an alkyd type, a silicone type or a fluorine type releasing agent But is not limited thereto.

Also, the kind of the second film (hereinafter sometimes referred to as " cover film ") that can be used in the present application is not particularly limited either. For example, in the present application, as the second film, the same or a different kind as the first film may be used within the scope exemplified in the first film described above. In the present application, the second film may also be subjected to appropriate mold release treatment.

The thickness of the pressure-sensitive adhesive layer included in the pressure-sensitive adhesive film of the present application is not particularly limited and may be appropriately selected in accordance with the following conditions in consideration of the application to which the film is applied. The thickness of the pressure-sensitive adhesive layer included in the pressure-sensitive adhesive film of the present application may be about 5 占 퐉 to 200 占 퐉, preferably about 10 占 퐉 to 150 占 퐉.

In addition, the pressure-sensitive adhesive film may have excellent light transmittance with respect to the visible light region. In one example, the pressure-sensitive adhesive film of the present application can exhibit a light transmittance of 85% or more with respect to the visible light region. For example, the adhesive film may have a light transmittance of 87% or more or 89% or more with respect to the visible light region. Further, the pressure-sensitive adhesive film of the present application can exhibit low haze with excellent light transmittance. In one example, the adhesive film may exhibit a haze of 3% or less, 2.8% or less, or 2.5% or less. The optical characteristics may be measured at 550 nm using a UV-Vis spectrometer.

The present application also relates to a method for producing the aforementioned pressure-sensitive adhesive composition. In one example, the method may comprise modifying the base resin and the curable compound of the pressure-sensitive adhesive composition. The modifying step may be a step of epoxidizing an unsaturated group of the base resin and the curable compound to introduce a reactive functional group. Specifically, the epoxidation can be carried out using the oxidizing agent described above.

The present application also includes a substrate 21; An organic electronic device 23 formed on one surface of the substrate 21; And the above-described adhesive film (24) formed on the other surface of the substrate (21). Further, the sealing member 12 sealing the organic electronic device 23 may be further included. The sealing material may include, but is not limited to, the above-described pressure-sensitive adhesive composition.

The organic electronic device in the present application may be an organic light emitting diode.

The organic electronic device may further include a protective film for protecting the device.

The organic electronic device may further include a cover substrate 22 covering the top of the encapsulant 12.

The present application also relates to a method of manufacturing an organic electronic device comprising the step of forming an adhesive film comprising the aforementioned adhesive composition on the other side of a substrate on which an organic electronic device is formed.

The manufacturing method may further include a step of crosslinking or curing the adhesive film.

In addition, the adhesive film exhibits excellent transparency and can be formed as a stable adhesive film regardless of the form of the organic electronic device such as top emission or bottom emission.

As used herein, the term " curing " means that the adhesive composition of the present invention forms a cross-linked structure through heating or UV irradiation, etc., and is produced in the form of a pressure-sensitive adhesive.

Specifically, a transparent electrode is formed on a glass or polymer film used as a substrate by a method such as vacuum deposition or sputtering. On the transparent electrode, a light-emitting organic material composed of a hole transporting layer, a light- And then an electrode layer is further formed on the electrode layer to form an organic electronic device.

Then, the adhesive film is placed on the other surface of the substrate, and the adhesive film is heated using a laminate or the like to press the adhesive film in a state of imparting fluidity, and the resin in the adhesive film can be crosslinked.

The present application provides a pressure-sensitive adhesive composition which is capable of effectively blocking moisture or oxygen introduced into an organic electronic device from the outside, has excellent durability and optical characteristics, and an adhesive film containing the pressure-sensitive adhesive composition.

1 is a cross-sectional view showing an organic electronic device according to one example of the present invention.

Hereinafter, the present invention will be described in more detail with reference to the following examples and comparative examples, but the scope of the present invention is not limited by the following examples.

Base resin manufacturing

Manufacturing example  One

100 parts by weight of toluene and 15 parts by weight of isobutylisoprene rubber (IIR, Lanxess RB301) were charged into a sealable 500 mL reaction vessel and stirred at room temperature until the rubber melted. Then, 15 parts by weight of acetone, 8 parts by weight of sodium bicarbonate dissolved in water and 15 parts by weight of oxon (potassium peroxomonosulfate) were added to the reaction vessel, and the mixture was stirred at room temperature for about 20 hours to conduct the reaction. Thereafter, separation was carried out using the difference in density between the solvent toluene and water, and a modified base resin was obtained.

Curable compound manufacturing

Manufacturing example  2

100 parts by weight of toluene and 100 parts by weight of dicyclopentadiene (DCPD, Sigma-Aldrich) were added to a sealable 500 mL reaction vessel, and the mixture was stirred at room temperature. Then, 40 parts by weight of acetone, 12 parts by weight of sodium bicarbonate dissolved in water, and 48 parts by weight of oxon (potassium peroxomonosulfate) were added to the reaction vessel, and the mixture was stirred at room temperature for about 10 hours to conduct the reaction. Thereafter, separation was performed using the difference in density between the solvent toluene and water, and the modified curable compound 1 was obtained.

Manufacturing example  3

A curable compound was prepared in the same manner as in Production Example 2 except that a terpene-phenol resin (DERTOPHENE T115, DRT) was used in place of dicyclopentadiene (DCPD, Sigma-Aldrich) to obtain a curable compound 2.

Example  One

75 g of the base resin obtained in Preparation Example 1 and 500 g of toluene were placed in a mixing vessel and 30 parts by weight of the curable compound 1 prepared in Production Example 2 as a curable compound with respect to 100 parts by weight of the base resin was charged into the container . Further, a terphene phenolic tackifier (DERTOPHENE T115, DRT) was added to the vessel in an amount of 40 parts by weight based on 100 parts by weight of the base resin. 1.5 parts by weight of a non-antimony photoinitiator (CPI-200K, San-Apro Ltd.) was added to 100 parts by weight of the base resin.

A homogeneous pressure-sensitive adhesive composition solution (solvent: toluene) was prepared using a conventional mechanical stirrer as the mixing container.

The prepared solution was coated on the release surface of the release PET and dried (5 atm) in an oven at 130 deg. C for 3 minutes to produce an adhesive film comprising a pressure-sensitive adhesive layer having a thickness of 50 mu m. The properties of the produced film were measured for a sample irradiated with 2 J / cm ² (100 mW / cm ^{2 on the} A region basis) of ultraviolet rays under a nitrogen atmosphere.

Example  2

10 parts by weight of the curable compound 1 prepared in Production Example 2 as a curable compound with respect to 100 parts by weight of the base resin and 10 parts by weight of 3-ethyl-3 - [(3-ethyloxetan-3-yl) methoxymethyl] oxetane (OXT-221, Toagossei) was added to a container in an amount of 10 parts by weight based on 100 parts by weight of the base resin, to thereby produce an adhesive film.

Example  3

20 parts by weight of the curable compound 1 prepared in Preparation Example 2 as a curable compound with respect to 100 parts by weight of the base resin and 20 parts by weight of 3-ethyl-3 - [(3-ethyloxetan-3- yl) methoxymethyl] oxetane An adhesive film was prepared in the same manner as in Example 1, except that 20 parts by weight of OXT-221 (Toagossei) was added to 100 parts by weight of the base resin.

Example  4

As the curable compound, the curable compound 1 prepared in Preparation Example 2 was added in an amount of 21 parts by weight based on 100 parts by weight of the base resin and 3 parts by weight of 3-ethyl-3- [(3-ethyloxetan-3-yl) methoxymethyl] oxetane (OXT-221, Toagossei) were added to a container in an amount of 9 parts by weight based on 100 parts by weight of the base resin, and 60 parts by weight of a terpene phenolic tackifier (DERTOPHENE T115, DRT) To prepare an adhesive film in the same manner as in Example 1.

Example  5

The curable compound 1 prepared in Preparation Example 2 as a curable compound was added in an amount of 7.5 parts by weight based on 100 parts by weight of the base resin and 3 parts by weight of 3-ethyl-3 - [(3-ethyloxetan-3-yl) methoxymethyl] oxetane (OXT-221, manufactured by Toagossei) was added to a container in an amount of 17.5 parts by weight based on 100 parts by weight of the base resin, and 60 parts by weight of a terphene phenolic tackifier (DERTOPHENE T115, DRT) To prepare an adhesive film in the same manner as in Example 1.

Example  6

60 parts by weight of the curable compound 2 prepared in Preparation Example 3 as a curable compound was added to the above base resin in an amount of 60 parts by weight based on 100 parts by weight of the base resin and a non-antimony photoinitiator (CPI-200K, San- Apro Ltd.) was added to the container in an amount of 0.5 part by weight based on 100 parts by weight of the base resin, to thereby produce an adhesive film.

Comparative Example  One

30 parts by weight of 3-ethyl-3 - [(3-ethyloxetan-3-yl) methoxymethyl] oxetane (OXT-221, Toagossei) as a curable compound was added to the above- And an adhesive film was prepared in the same manner as in Example 1, except that 60 parts by weight of a terpene phenolic tackifier (DERTOPHENE T115, DRT) was added to 100 parts by weight of the base resin.

Comparative Example  2

An adhesive film was prepared in the same manner as in Comparative Example 1, except that 30 parts by weight of an alicyclic epoxy compound (Celloxide 2021P, DAICEL) as a curable compound was added to 100 parts by weight of the base resin.

The properties of the base resin, pressure-sensitive adhesive composition and pressure-sensitive adhesive film prepared in Examples and Comparative Examples were measured as follows.

One. Gel content

Gel content (% by weight) = B / A x 100

B represents the mass of the pressure-sensitive adhesive composition; and B represents the mass of the pressure-sensitive adhesive composition obtained by immersing the pressure-sensitive adhesive composition in toluene at 25 ° C for 24 hours, filtering it with a mesh of 200 mesh (pore size 74 μm) It represents the dry weight of the insoluble fraction of the composition.

2. Creep

A substrate film having a thickness of 30 占 퐉 formed on one side of a pressure-sensitive adhesive layer (1 cm wide and 12 cm long) having a thickness of 30 占 퐉 formed using the pressure-sensitive adhesive compositions of Examples and Comparative Examples was attached to a glass plate at an adhesion area of 1 cm ² , aged for 24 hours, , The pushing distance of the pressure-sensitive adhesive layer was measured when a load of 1.5 kg was applied for 1000 seconds. The base film used was a polyethylene terephthalate (PET) film.

However, when the pressure-sensitive adhesive layer was separated from the attached glass plate, it was classified as a drop-off.

3. Light transmittance  And Hayes

The pressure-sensitive adhesive films of Examples and Comparative Examples were laminated on a 50 mm x 50 mm glass substrate, stored at room temperature for 24 hours, and then measured for light transmittance and haze using a haze meter (COH-400, Nippon Denshoku).

The measurement results are summarized in Table 1 below.

Example Comparative Example One 2 3 4 5 6 One 2 Haze
(%) 1.49 1.45 2.29 1.20 1.57 0.98 3.15 4.31 Permeability
(%) 89.3 91.0 90.2 91.3 91.0 90.6 91.0 91.0 Come
(%) 57 65.5 57.0 61.7 63.3 25 70 27.0 Creep
(탆) 924 649 567 689 864 776 460 leaving out

21: substrate
22: Cover substrate
23: Organic electronic device
24: Adhesive film
12: Encapsulation material

Claims (18)

1. A pressure-sensitive adhesive composition comprising an olefin-based compound as a polymerization unit, a base resin containing at least one reactive functional group, and a curable compound having a lyotropic structure in a molecular structure. The curable composition according to claim 1, wherein the curable compound comprises at least one curable functional group, and the curable functional group is at least one selected from the group consisting of a glycidyl group, an isocyanate group, a hydroxyl group, a carboxyl group, an amide group, an epoxide group, a cyclic ether group, And a lactone group. The pressure-sensitive adhesive composition according to claim 1, wherein the curable compound has a ring constituent atom in a range of 5 to 20. The pressure-sensitive adhesive composition according to claim 1, wherein the curable compound is contained in an amount of 5 to 80 parts by weight based on 100 parts by weight of the base resin. The pressure-sensitive adhesive composition according to claim 1, wherein the base resin has an integral ratio (R) of 10% or less as represented by the following general formula (1)
[Formula 1]
R = H / (E + H) x 100
In the general formula (1), E represents the integration area of the peak due to the reactive functional group in 1 H-NMR, and H represents the integration area of the peak due to the hydroxyl group. The pressure-sensitive adhesive composition according to claim 1, wherein the reactive functional group is an epoxidized unsaturated group of the base resin. The pressure-sensitive adhesive composition according to claim 6, wherein the unsaturated group has an epoxy conversion of 70 mol% or more. The pressure-sensitive adhesive composition according to claim 1, wherein the base resin has an epoxy equivalent of 100 g / eq to 20,000 g / eq. The pressure-sensitive adhesive composition according to claim 1, wherein the base resin has a number-average molecular weight in the range of 100,000 to 1,000,000. The pressure-sensitive adhesive composition according to claim 1, wherein the gel content according to the following general formula (2) is 20% or more:
[Formula 2]
Gel content (% by weight) = B / A x 100
In the general formula 2, A represents the mass of the pressure-sensitive adhesive composition, and B represents the mass of the pressure-sensitive adhesive composition. The pressure-sensitive adhesive composition is immersed in toluene at 25 ° C for 24 hours, filtered through a mesh of 200 mesh (pore size 74 μm) The dry mass of the insoluble component of the pressure-sensitive adhesive composition. The pressure-sensitive adhesive composition according to claim 1, which has a cyclic structure after curing. The pressure-sensitive adhesive composition according to claim 1, further comprising a tackifier. The pressure-sensitive adhesive composition according to claim 12, wherein the tackifier is contained in an amount of 10 to 100 parts by weight based on 100 parts by weight of the base resin. The pressure-sensitive adhesive composition according to claim 1, further comprising a curing agent or an initiator. A pressure-sensitive adhesive film comprising the pressure-sensitive adhesive composition according to claim 1. 16. The adhesive film according to claim 15, wherein the adhesive film exhibits a haze of 3% or less. Board; An organic electronic device formed on one surface of the substrate; And an adhesive film according to claim 15 formed on the other surface of the substrate. Forming an adhesive film according to claim 15 on another surface of a substrate on which an organic electronic device is formed on one surface; And a step of curing the adhesive film.

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