KR20180021583A - 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 temperatures and high humidity but also excellent optical characteristics, and an adhesive film comprising the same. The adhesive agent composition comprises: an olefin-based compound as a polymerization unit; a base resin having at least one reactive functional group and having a hydroxyl group area ratio (R) of 10% or less.

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.

As used herein, the term " organic electronic device " refers to 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. The base resin may include an olefinic compound as a polymerization unit, and may include at least one reactive functional group. In addition, the base resin may have an integral ratio (R) of hydroxyl groups represented by the following general formula (1): 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 pressure-sensitive adhesive composition may have a haze of 3% or less, 2.5% or less, 2% or 1.5% or less when manufactured into a film. The method of measuring the haze is not particularly limited and can be carried out in a known manner. For example, it may be measured at 550 nm using a UV-Vis spectrometer.

Since the pressure-sensitive adhesive composition of the present application contains a base resin having an areal ratio of hydroxyl groups of 10% or less as represented by the above-mentioned general formula 1, it is possible to secure an appropriate range of crosslinking structure and degree of crosslinking without using a separate curing resin, It is possible to prevent the problem that the optical characteristics are lowered due to the compatibility of the base resin and the curable resin.

In one embodiment of the present application, the pressure-sensitive adhesive composition may satisfy the following general formula (2).

[Formula 2]

DELTA X ≤

In the general formula 2, 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 adhered 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 2 may be 1000 占 퐉 or less, 10 to 900 占 퐉, 100 to 880 占 퐉 or less, or 200 to 850 占 퐉.

Since the pressure-sensitive adhesive composition of the present application contains a base resin having an areal ratio of hydroxyl groups of 10% or less as represented by the above-mentioned general formula 1, the crosslinking structure and degree of crosslinking in an appropriate range can be secured without using a separate curing resin, It can be controlled to be 1000 占 퐉 or less. In particular, the pressure-sensitive adhesive composition according to the present invention can be manufactured into a film and can realize excellent moisture barrier properties, durability and optical characteristics when applied to an organic electronic device.

In one example, the pressure-sensitive adhesive composition of the present application may not contain a curable resin. In general, a pressure-sensitive adhesive composition uses a separate curable resin in order to form a dense cross-linked density. However, such a curable resin may have a limitation in maintaining compatibility with the base resin, It may be difficult to secure optical characteristics. In contrast, the pressure-sensitive adhesive composition according to the present application contains a base resin in which the area ratio of the hydroxyl groups is 10% or less, so that a dense crosslinked structure can be formed without using a separate curing resin, At the same time, can be produced as an adhesive film having excellent moisture barrier properties and durability.

In one example, the curable resin not including the pressure-sensitive adhesive composition of the present application may be an epoxy compound or a multi-functional acrylate.

Specifically, as the polyfunctional acrylate, for example, tricyclodecane dimethanol di (meth) acrylate is exemplified, but it is not limited thereto.

Examples of the epoxy compound include epoxidized linseed oil, epoxidized polybutadiene, polyisobutylene oxide,? -Pinene oxide, limonene dioxide, 3,4-epoxycyclohexylmethyl Tri-cyclodecane di-methanol diglycidyl ether, hydrogenated bisphenol A diglycidyl ether and 1,2-bis [(3-ethyl-3-oxe) Thanylmethoxy) methyl] benzene can be exemplified, but the present invention is not limited thereto.

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. In the present application, it is possible to introduce a reactive functional group into a desired range in the resin by controlling the area ratio of the hydroxyl group of the base resin to the above range, thereby realizing a dense crosslinked density, so that no separate curing resin can be used. Accordingly, it is possible to maintain excellent heat resistance, durability reliability and optical characteristics at high temperature and high humidity at the same time while realizing excellent moisture barrier property.

In addition, the polymer may have at least one reactive functional group. The reactive functional group may be an epoxidized form of the unsaturated group of the base resin. In one example, the reactive functional group may be in an epoxidized form of the unsaturated group of the backbone of the base resin. 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. By using only the base resin having a reactive functional group, the present invention can maintain excellent heat resistance, durability and optical properties at high temperature and high humidity at the same time while realizing excellent moisture barrier property.

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.

In the embodiment of the present application, the reactive functional group may be an epoxy group, and specifically, the unsaturated group of the base resin may be an epoxidized epoxy group. 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 form 1,2-epoxide

The epoxidation may 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 base resin 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 one example, the epoxy conversion of the unsaturated group of the base resin may be at least 70 mole%. As the epoxy conversion rate is higher, a dense crosslinking density can be formed only by the base resin itself, thereby realizing excellent transparency, increasing internal stress, and providing a highly reliable sealing material. 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 invention can form a dense crosslinked density only by the base resin itself without using a separate curable resin, thereby realizing excellent transparency and increasing internal stress, Provide ashes.

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.

In embodiments of the present application, the pressure-sensitive adhesive composition may have a cyclic structure after curing. The annular structure may be derived from a base resin. By applying the pressure-sensitive adhesive of the above structure, the present application can realize a stable crosslinking structure against external factors such as shrinkage and expansion even after crosslinking or curing.

In one example, the pressure sensitive adhesive composition of the present application may further comprise a tackifier. Examples of the tackifier include a hydrocarbon resin or hydrogenated product thereof, a rosin resin or hydrogenated product thereof, a rosin ester resin or hydrogenated product thereof, a terpene resin or hydrogenated product thereof, a terpene phenol resin or hydrogenated product thereof, Polymerized rosin ester resin, and the like, or a mixture of two or more of them may be used, but the present invention is not limited thereto.

In one embodiment, the tackifier of the present application may be a hydrocarbon resin or a terpene phenolic resin. The present application is based on the finding that by using the above-mentioned hydrocarbon resin or terpene phenol resin as the tackifier, it has excellent adhesion and compatibility with the base resin, thereby improving the crosslinking density while maintaining excellent optical properties, An adhesive can be provided.

The tackifier may be included in an amount of 40 to 100 parts by weight, 45 to 90 parts by weight, 50 to 90 parts by weight, 55 to 80 parts by weight, 60 to 70 parts by weight or 55 to 65 parts by weight based on 100 parts by weight of the base resin . Within the above weight range, the tackifier is excellent in compatibility with the base resin, and can provide an adhesive excellent in optical properties and in crosslinking density and excellent in durability reliability.

In the embodiments 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. For example, a curing agent capable of reacting with the above-mentioned base resin 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 kind and ratio of the base resin. For example, the curing agent may be contained in an amount of 1 to 20 parts by weight, 1 to 10 parts by weight, or 1 to 5 parts by weight based on 100 parts by weight of the base resin. However, the weight ratio may be changed depending on the kind and ratio of the functional group of the base resin or the compound, the crosslinking density to be implemented, and the like.

In one example, as the initiator, for example, a cationic photopolymerization initiator may be used.

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 specification, unless otherwise specified, the unit " weight part " 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.

Further, the pressure-sensitive adhesive composition according to the present application may have a gel content of 30% or more according to the following general formula (3).

[Formula 3]

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

In the general formula (3), A 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 and then filtering it through a mesh of 200 mesh The dry mass of the insoluble component of the pressure-sensitive adhesive composition.

The gel content represented by the general formula 3 may be 30% to 95%, 35% to 90%, or 40% to 85%. 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 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 90% 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, 2.5% or less, 2% or 1.5% 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 of the pressure-sensitive adhesive composition. The modifying step may be a step of epoxidizing an unsaturated group of the base resin to introduce a reactive functional group. Specifically, the epoxidation can be carried out using the oxidizing agent described above.

In one example, the base resin may satisfy the following general formula (4).

[Formula 4]

X ≥ pH 5

In the general formula (4), X represents a pH of a mixture comprising 100 parts by weight of purified water having a pH of 6.04 at 83 캜 and 10 parts by weight of the base resin relative to 100 parts by weight of the purified water at 83 캜.

In the present application, the side reaction due to high acidity can be suppressed by controlling the pH of the base resin to 5 or more during the modification step. That is, when the pH of the base resin is less than 5 during the reforming step, a side reaction occurs due to a high acidity, and a large amount of hydroxyl groups can be formed. In addition, after the reforming step, a separate washing or refining step is required to neutralize the high acidity, so that it may not be suitable for mass production considering cost and productivity.

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.

Manufacturing example

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.

Example  One

75 g of the base resin obtained in the above Production Example and 500 g of toluene were put into a mixing vessel. Further, a terphene phenolic tackifier (DERTOPHENE T 115, manufactured by DRT) was added to the vessel in an amount of 60 parts by weight based on 100 parts by weight of the base resin. One part by weight of a non-antimony photoinitiator (CPI-200K, San-Apro Ltd.) was added to the container in 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

An adhesive film was prepared in the same manner as in Example 1, except that a hydrocarbons-based tackifier (Regalite R1100, Eastman) was used instead of the terpene phenol-based tackifier (DERTOPHENE T 115, DRT) as the tackifier .

Comparative Example  One

(IIR, Lanxess RB301) was used in place of the base resin obtained in Production Example, and 40 parts by weight of a terpene phenolic tackifier (DERTOPHENE T 115, DRT Co.) was added to 100 parts by weight of the base resin , An adhesive film was produced in the same manner as in Example 1.

Comparative Example  2

75 g of isobutylisoprene rubber (IIR, Lanxess RB301) and 500 g of toluene were placed in a mixing vessel, and tricyclodecane dimethanol di (meth) acrylate (Miramer M262, Miwon) 17 parts by weight based on 100 parts by weight of the mixture. Further, a tackifier for terpene phenol (DERTOPHENE T115, manufactured by DRT Co.) was added to the container in an amount of 40 parts by weight based on 100 parts by weight of the base resin. 1.2 parts by weight of a non-antimony-based 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 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 and a pressure-sensitive adhesive layer (width 1 cm, length 12 cm) formed on one surface thereof, which was formed using the pressure-sensitive adhesive compositions of Examples and Comparative Examples, was attached to a glass plate with an adhesive area of 1 cm x 1 cm, aged for 24 hours, When the load of 1.5 kg was applied for 1000 seconds, the pushing distance of the pressure-sensitive adhesive layer was measured. 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 adhesive films of Examples and Comparative Examples were laminated on a 50 mm x 50 mm glass substrate and stored at room temperature for 24 hours, and haze and light transmittance were measured using a haze meter (COH-400, Nippon Denshoku).

4. NMR measurement

¹ H-NMR analysis was performed at room temperature using an NMR spectrometer including a Varian Unity Inova (500 MHz) spectrometer with a triple resonance 5 mm probe. The analytes were diluted to a concentration of about 10 mg / ml in a solvent for NMR measurement (CDCl ₃ ).

^{In the 1} H-NMR spectrum, the hydroxyl group ratio (R) was measured according to the aforementioned general formula (1). The area of the peak was calculated using the MestReC program.

The measurement results are summarized in Table 1 below.

Haze (%) Permeability (%) Gel (%) Creep (탆) R (%) Example 1 1.18 90.4 60.32 710 0 Example 2 1.11 91.34 57.86 569 0 Comparative Example 1 0.93 91.33 0 leaving out - Comparative Example 2 3.05 91.63 60.6 leaving out -

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

Claims (16)

A base resin comprising an olefinic compound as a polymerization unit and containing at least one reactive functional group and having a hydroxyl group area ratio (R) of 10% or less represented by the following general formula (1) % Or less Pressure sensitive adhesive composition:
[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 pressure-sensitive adhesive composition according to claim 1, which satisfies the following general formula (2):
[Formula 2]
DELTA X ≤
In the general formula 2, 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 [micro] m and a substrate film having the pressure-sensitive adhesive layer formed on one side thereof is adhered 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 pressure-sensitive adhesive composition according to claim 1, which does not comprise a curable resin. The pressure-sensitive adhesive composition according to claim 3, wherein the curable resin is an epoxy compound or a multi-functional acrylate. 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 5, 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 (3) is 30% or more:
[Formula 3]
Gel content (% by weight) = B / A x 100
In the general formula (3), A 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 and then filtering it through a mesh of 200 mesh The dry mass of the insoluble component of the pressure-sensitive adhesive composition. The pressure-sensitive adhesive composition according to claim 1, further comprising a tackifier. The pressure-sensitive adhesive composition according to claim 10, wherein the tackifier is contained in an amount of 40 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. 14. The adhesive film according to claim 13, wherein the adhesive film exhibits a light transmittance of 90% or more with respect to the visible light region. Board; An organic electronic device formed on one surface of the substrate; And an adhesive film according to claim 13 formed on the other surface of the substrate. Forming an adhesive film according to claim 13 on another surface of a substrate on which an organic electronic element is formed on one surface; And a step of curing the adhesive film.

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