Adhesive composition, adhesive layer, and display device comprising same

Abstract

An adhesive composition that implements impact resistance and excellent transparency and, simultaneously, exhibits low viscosity is disclosed. According to one aspect, the adhesive composition is provided, the composition comprising: a base material including an acrylic monomer and an oligomer; an initiator; and core-shell rubber particles including a core part and a shell part, wherein the elastic modulus of the core part is 0.1 MPa or more under conditions of 25℃, 5.0% strain, and a frequency of 10.0 Hz on the basis of a dynamic mechanical analysis (DMA) analysis method, and the shell part is chemically bonded to the core part and has a viscosity of 50 cp or less at 25℃ and 1,350 s-1.

Description

Adhesive composition, adhesive layer and display device comprising the same The present disclosure relates to an adhesive composition, and more specifically, to an adhesive composition, an adhesive layer, and a display device including the same. The display device includes a display panel and a window. Pixels are arranged on the display panel, and an image is displayed using the pixels. The image can be viewed by a user through the window. Meanwhile, an adhesive layer may be placed between the display panel and the window. For example, the adhesive layer may be a cured adhesive composition, and the adhesive composition may be a polymer resin having adhesive properties, and may be discharged in a liquid form through an inkjet process and then cured through a curing process. According to one aspect of the present invention, an adhesive composition having excellent transparency, improved optical properties, and low viscosity is provided. According to another aspect of the present invention, an adhesive composition having excellent light resistance is provided. According to another aspect of the present invention, an adhesive composition is provided that improves compression resistance or impact resistance. According to another aspect of the present invention, an adhesive layer having excellent optical properties and improved compression resistance under high compression ratio conditions is provided. According to another aspect of the present invention, a display device having improved reliability and performance is provided. The purposes of the present invention are not limited to the purposes mentioned above, and other purposes and advantages of the present invention that are not mentioned can be understood by the following description, and will be more clearly understood by the embodiments of the present invention. In addition, it will be easily understood that the purposes and advantages of the present invention can be realized by the means and combinations thereof described in the specification. According to a first aspect of the present invention, there is provided a core-shell rubber particle comprising a base material including an acrylic monomer and an oligomer; an initiator; and core-shell rubber particles including a core portion and a shell portion; wherein, according to a DMA (Dynamic Mechanical Analysis) analysis method, under the conditions of 25°C, a strain of 5.0%, and a frequency of 10.0 Hz, an elastic modulus of the core portion is 0.1 MPa or more, and the shell portion is chemically bonded to the core portion, and has a thermal conductivity of 0.1 MPa or more at 25°C and 1,350 s. -1 An adhesive composition having a viscosity of 50 cP or less is provided. According to the second aspect of the present invention, the acrylic monomer may include at least one of the compounds represented by the following chemical formulas 1 and 2. [Chemical Formula 1] [Chemical formula 2] In the above chemical formulas 1 and 2, R1 and R2 are each independently hydrogen; deuterium; an alkyl group having 1 to 20 carbon atoms, wherein at least one hydrogen atom is substituted or unsubstituted with a hydroxy group; or a substituted or unsubstituted aromatic ring group having 3 to 20 carbon atoms. According to a third aspect of the present invention, in the first or second aspect, the oligomer may include at least one or more of a structure derived from an acrylic group, a urethane group, an epoxy group, a siloxane group, and an ester group. According to the fourth aspect of the present invention, in any one of the first to third aspects, the weight average molecular weight of the oligomer may be 2,000 g / mol or more and 15,000 g / mol or less. According to the fifth aspect of the present invention, in any one of the first to fourth aspects, the glass transition temperature of the oligomer may be -80°C or higher and 20°C or lower. According to the sixth aspect of the present invention, in any one of the first to fifth aspects, the weight ratio of the oligomer and the acrylic monomer may be 1:1 or more and 1:17 or less. According to the seventh aspect of the present invention, in any one of the first to sixth aspects, the particle size (D) of the core-shell rubber particles 50 ) can be 0.1 nm or more and 100 nm or less. According to the eighth aspect of the present invention, in any one of the first to seventh aspects, the content of the core-shell rubber particles may be 0.1 part by weight or more and 20 parts by weight or less with respect to 90 parts by weight of the base material. According to the ninth aspect of the present invention, in any one of the first to eighth aspects, the content of the core-shell rubber particles may be more than 1 part by weight and less than 5 parts by weight with respect to 90 parts by weight of the base material. According to a tenth aspect of the present invention, in any one of the first to ninth aspects, the core portion may include a structure of at least one of an acrylic compound, a diene compound, and a urethane compound, and the shell portion may include a structure of a compound having a reactive functional group that chemically bonds with the base material. According to the eleventh aspect of the present invention, in the tenth aspect, the reactive functional group may include a carbon-carbon unsaturated bond. According to the twelfth aspect of the present invention, in any one of the first to eleventh aspects, the weight ratio of the core portion and the shell portion may be 1:0.1 or more and 1:10 or less. According to the thirteenth aspect of the present invention, in any one of the first to twelfth aspects, the ratio of the particle size of the core portion to the thickness of the shell portion (particle size of the core portion: thickness of the shell portion) may be 1:0.1 or more and 1:1 or less. According to the 14th aspect of the present invention, there is provided an adhesive layer comprising a polymer matrix including an acrylic resin; and core-shell rubber particles; wherein the adhesive layer has a compressive strength of 0.2 MPa or more and 1.5 MPa or less for a specimen having a thickness of 10 mm under conditions of a compression speed of 5 mm / min and a compression ratio of 50%, and is irradiated with light having a wavelength of 380 to 780 nm at 500 mW / cm. 2 An adhesive layer is provided having a yellow index of 4.80 or less after exposure to a dose of 250 hours. The adhesive layer may be a cured adhesive composition having at least one of the characteristics of the first to thirteenth aspects. According to a fifteenth aspect of the present invention, a display device including an adhesive layer according to the fourteenth aspect is provided. The above-mentioned solution to the problem does not enumerate all the features of the present invention. The various features of the present invention and the advantages and effects thereof can be understood in more detail by referring to the specific description below. According to one aspect of the present invention, it is possible to implement an adhesive composition having excellent impact resistance and transparency while having low viscosity. According to another aspect of the present invention, an adhesive composition having excellent transparency even after long-term UV irradiation can be implemented. In addition to the effects described above, the specific effects of the present invention are described together with the specific contents for carrying out the invention below. In addition, the effects of the present invention are not limited to the effects mentioned above, and can be easily implemented by the means and combinations thereof described in the specification. Figure 1 is a cross-sectional view showing a display device according to one embodiment of the present invention. In this specification, singular expressions include plural expressions unless the context clearly indicates otherwise. For example, in this specification, each component may contain multiple types of the corresponding substance. When multiple types of substances corresponding to each component exist in the composition, the content rate or content of each component may mean the content rate or content of the sum of the multiple types of substances present in the composition, unless otherwise specified. For example, particles corresponding to each component may contain multiple types. When multiple types of particles corresponding to each component exist in the composition, the particle size of each component may mean a value for a mixture of the multiple types of particles present in the composition, unless otherwise specified. In this specification, “At least one of a, b and c” may include a, b or c alone, or a combination of two or more selected from the group consisting of a, b and c. When several embodiments are described in this specification, each embodiment may be combined unless there is a special description to the contrary. In this case, the effect of the present invention may be defined as including the effect derived from each embodiment and the effect generated when each embodiment is organically combined. For example, even if Embodiments 1 and 2 are described independently in this specification, Embodiments 1 and 2 may be organically combined with each other unless the context clearly indicates otherwise, and the effect of the present invention may include the effect generated when Embodiments 1 and 2 are combined. The numerical range indicated by the term 'to' in this specification indicates a numerical range that includes the values ​​described before and after the term as the lower and upper limits, respectively. For example, if a to b are described in the specification, it can be understood that a to b (a~b) is described. In the present specification, when the upper and lower limits of any numerical range are each disclosed as multiple numbers, the numerical range disclosed in the present specification can be understood as any numerical range that uses any one of the multiple lower limit values ​​and any one of the multiple upper limit values ​​as the lower limit value and the upper limit value, respectively. For example, when a or more, or b or more; and c or less, or d or less are described, it can be understood that a or more and c or less, a or more and d or less, b or more and c or less, or b or more and d or less are described. In this specification, terms such as "about" or "substantially" mean a reasonable amount of variation of the term so that the final result is not significantly changed. Such terms may be interpreted to include a variation of at least ±5% or at least ±10%, provided that the variation does not invalidate the meaning of the word. In this specification, the term "layer" or film may include cases where the layer or film is formed not only over the entire area when observing the area where the layer or film exists, but also cases where the layer or film is formed over only a portion of the area. For example, the surface of the layer or film may be defined to include a flat shape, a non-flat shape, and a combination thereof; or a continuous shape, a discontinuous shape, and a combination thereof. For example, when another element is formed as a layer or film directly on top of one element, the coverage of the other element over the one element may be defined as 1% or more, 5% or more, 10% or more, 20% or more, 30% or more, 40% or more, 50% or more, 60% or more, 70% or more, 80% or more, 85% or more, 90% or more, 95% or more, or 99% or more. In this specification, the "particle size" of a particle is the particle size (D) when the cumulative percentage becomes 50% in a volume-based particle size distribution curve when measured by a laser diffraction particle size distribution measuring device.50 ) can be defined as. In this specification, the "weight average molecular weight" or "number average molecular weight" refers to a standard polystyrene-converted molecular weight, which can be analyzed by a GPC (gel permeation chromatography) device. For example, in the case of a GPC analysis method, the developing solvent may be tetrahydrofuran (THF), the column may be PL Olexis of Polymer Laboratories, the sample concentration may be 5 mg / mL, the sample injection amount may be 100 ㎕, the flow rate may be 1 mL / min, the detector may be Agilent High Temperature RI detector, and the column temperature may be set to 40°C. In this specification, “oligomer” may be defined as a compound having a weight average molecular weight of about 2000 g / mol or more and 15,000 g / mol or less. In this specification, “acrylic” may be defined as containing at least one of a (meth)acryloyl group and an acryloyl group in one molecule. As used herein, "substituted" means, unless otherwise defined below, a group in which at least one hydrogen atom is substituted with a halogen atom, a hydroxyl group, a carboxyl group, a nitro group, an amine group, a sulfide group, a thiol group, an alkoxy group, an acetoxy group, a nitrile group, an aldehyde group, an ether group, an ester group, an acetal group, a ketone group, a C1 to C 30 Alkyl group of C2 to C 30 Alkenyl group of C2 to C 30 Alkynyl group, C1 to C 40 Alkylsilyl group, C5 to C 40 Arylsilyl group, C3 to C 30 Cycloalkyl group of C3 to C 30 Announcement of C6 to C 30 Aryl group, heterocyclic group (e.g. C2 to C) 30 Heterocycloalkyl group of C3 to C 30is defined as being replaced by any one selected from the group consisting of a heteroaryl group of a compound of formula (I), a derivative thereof, and a combination thereof. Here, each of the substituents may be combined with each other when adjacent to each other to form a substituted or unsubstituted fused ring or spiro structure. The term "chemically bonded" in this specification may mean covalently bonded. For example, in core-shell rubber particles, if the material of the core portion and the material of the shell portion form a covalent bond with each other, it can be analyzed by FT-IR (Fourier-transform infrared spectroscopy) analysis. In this specification, the "elastic modulus" can be analyzed under the conditions of 25°C, strain 5.0%, and frequency 10.0 Hz in accordance with the DMA (Dynamic Mechanical Analysis) analysis method. For example, in the DMA analysis method, the heating rate can be set to 5°C / min, and the load capacity can be set to 0.0001 to 18 N. In this specification, “composition” may mean a mixture of materials including the composition, a reaction product formed from the materials of the composition, or a decomposition product. For example, the content and weight ratio of materials in the composition may be measured using a flame ionization detector (FID) after phase separation using gas chromatography. Specifically, the content of the material may be analyzed using a gas chromatography device of Agilent (product name: Agilent 7890 GC, column: HP-5, carrier gas: helium (flow rate 2.4 mL / min), detector: FID, injection volume: 1 uL, initial value: 70°C / 4.2 min, final value: 280°C / 7.8 min, program rate: 15°C / min). According to one aspect of the present invention, a core-shell rubber particle comprising a base material including an acrylic monomer and an oligomer; an initiator; and a core portion and a shell portion; wherein, according to a DMA (Dynamic Mechanical Analysis) analysis method, under the conditions of 25°C, a strain of 5.0%, and a frequency of 10.0 Hz, an elastic modulus of the core portion is 0.1 MPa or more, and the shell portion is chemically bonded to the core portion, and has a thermal conductivity of 0.1 MPa or more at 25°C and 1,350 s. -1 An adhesive composition having a viscosity of 50 cp or less is provided. According to one aspect of the present invention, by including core-shell rubber particles and controlling the viscosity of the adhesive composition within the above numerical range, the composition has high light transmittance and low haze and yellowness even after UV irradiation, thereby achieving excellent transparency and an effect of increasing the compressive strength of the adhesive layer. Below, the composition of the present invention is described in more detail. 1. Adhesive composition Base material The base material according to the present invention provides adhesiveness to the adhesive composition and can control the transparency of the adhesive layer and the viscosity of the adhesive composition. The base material according to the present invention includes an acrylic monomer and oligomer. The acrylic monomer according to the present invention is a monomer having a functional group including at least one of a (meth)acryloyl group and an acryloyl group, and may include one or more monomers having the functional group. In some embodiments of the present invention, the acrylic monomer may include at least one of the compounds represented by the following chemical formulas 1 and 2. [Chemical Formula 1] [Chemical formula 2] In the above chemical formulas 1 and 2, R1 and R2 are each independently hydrogen; deuterium; an alkyl group having 1 to 20 carbon atoms, wherein at least one hydrogen atom is substituted or unsubstituted with a hydroxy group; or a substituted or unsubstituted aromatic ring group having 2 to 20 carbon atoms. For example, the alkyl group may be a linear or branched alkyl group, and the aromatic ring group may include an aryl group or a heteroaryl group. For example, the acrylic monomer is not particularly limited, but may specifically include at least one of 2-ethylhexyl acrylate, isodecyl acrylate, 4-hydroxybutyl acrylate, methyl methacrylate, methyl acrylate, ethyl acrylate, butyl acrylate, and lauryl methacrylate. In some embodiments of the present invention, the acrylic monomer may include three or more kinds of acrylic monomers. According to some embodiments of the present invention, by using the three or more kinds of acrylic monomers, the adhesive layer may have excellent transparency and sufficient adhesive performance. For example, the three or more kinds of acrylic monomers may include a first monofunctional acrylate having a glass transition temperature of -40° C. or lower, a second monofunctional acrylate having a linear structure of 7 or more carbon atoms, and a third monofunctional acrylate having a hydroxyl group and a cyclic structure. In some embodiments of the present invention, the second monofunctional acrylate may be included in an amount of 20 parts by weight or more and 40 parts by weight or less, and the third monofunctional acrylate may be included in an amount of 20 parts by weight or more and 50 parts by weight or less, with respect to 20 parts by weight of the first monofunctional acrylate. Specifically, the second monofunctional acrylate may be included in an amount of 20 parts by weight or more and 30 parts by weight or less, and the third monofunctional acrylate may be included in an amount of 30 parts by weight or more and 40 parts by weight or less. According to some embodiments of the present invention, when the weight ratio of the first to third monofunctional acrylates is adjusted within the numerical range, the transparency of the adhesive layer can be further improved and the adhesive performance can be sufficiently achieved, and an adhesive layer having a high compressive strength even at a high compression ratio can be implemented. The oligomer according to the present invention can be blended with the above-described acrylic monomer to impart adhesive properties to the adhesive composition and control the transparency of the adhesive layer and the viscosity of the adhesive composition. In some embodiments of the present invention, the oligomer may include at least one or more of a structure derived from an acrylic group, a urethane group, an epoxy group, a siloxane group, and an ester group, and specifically, may include a urethane group and an acrylic group. In some examples, the structure derived from the epoxy group may include a divalent linking group composed of -CH2C(OH)H-. According to some embodiments of the present invention, by using a compound including both a urethane group and an acrylic group as the oligomer, excellent effects in strength, curing density, and curing speed of the adhesive layer can be implemented. Specifically, the oligomer having both a urethane group and an acrylic group is a compound in which the terminal of a urethane oligomer synthesized with an isocyanate compound and a polyol compound is reacted with an acrylic monomer, and the compressive strength of the adhesive layer can be further increased by the urethane group, and at the same time, the adhesiveness, transparency, and light resistance can be further improved by the acrylic functional groups at both terminals. In some embodiments of the present invention, the weight average molecular weight of the oligomer may be 2,000 g / mol or more and 15,000 g / mol or less, and specifically 2,000 g / mol or more, 2,500 g / mol or more, 3,000 g / mol or more, 3,500 g / mol or more, 4,000 g / mol or more, 4,500 g / mol or more, or 5,000 g / mol or more; And it may be 6,000 g / mol or less, 6,500 g / mol or less, 7,000 g / mol or less, 7,500 g / mol or less, 8,000 g / mol or less, 8,500 g / mol or less, 9,000 g / mol or less, 10,000 g / mol or less, 11,000 g / mol or less, 12,000 g / mol or less, 13,000 g / mol or less, 14,000 g / mol or less, or 15,000 g / mol or less, and more specifically, it may be 2,000 to 15,000 g / mol, 3,000 to 10,000 g / mol, 4,000 to 9,000 g / mol, or 5,000 to 6,000 g / mol. According to some embodiments of the present invention, the weight average molecular weight of the oligomer is adjusted to the above numerical range, so that the viscosity of the adhesive composition can be implemented at an appropriate level while having excellent adhesiveness. In some embodiments of the present invention, the glass transition temperature of the oligomer may be -80°C or more and 20°C or less, specifically -80°C or more, -70°C or more, or -65°C or more; and -60°C or less, -55°C or less, -50°C or less, -45°C or less, -40°C or less, -35°C or less, -30°C or less, -20°C or less, -10°C or less, 0°C or less, 5°C or less, 10°C or less, or 20°C or less, and more specifically -80 to 20°C, -70 to 5°C, -65 to 0°C, -65 to -10°C, -65 to -20°C, -65 to -30°C, -65 to -40°C, -65 to -55°C, or -65 to -60°C. In some embodiments of the present invention, the glass transition temperature of the oligomer is controlled within the above numerical range, so that the mechanical properties of the adhesive layer, such as the compressive strength, can be sufficiently improved while maintaining the adhesiveness at an appropriate level. For example, the glass transition temperature of the oligomer can be analyzed using a DSC (Differential Scanning Calorimetry) analysis method in accordance with ASTM E1356-23. In some embodiments of the present invention, the content of the acrylic monomer may be the same as or higher than the content of the oligomer, based on the total weight of the base material. According to some embodiments of the present invention, the content of the acrylic monomer is adjusted to be the same as or higher than the content of the oligomer, based on the total weight of the base material, thereby effectively preventing the viscosity of the adhesive composition from becoming excessively high, and accordingly, the adhesive composition may be well discharged in a liquid phase through an inkjet process, thereby providing excellent coatability and processability. In some embodiments of the present invention, the weight ratio of the oligomer and the acrylic monomer (oligomer: acrylic monomer) may be 1:1 or more and 1:17 or less, 1:1.25 or more and 1:8 or less, or 1:2 or more and 1:2.6 or less. According to some embodiments of the present invention, when the weight ratio of the acrylic monomer and the oligomer is adjusted within the above numerical range, the optical properties of the adhesive layer can be further improved, and the adhesive performance can be sufficiently achieved, and an adhesive layer having a high compressive strength even at a high compression ratio can be implemented. Initiator The initiator according to the present invention can initiate and accelerate a polymerization reaction. Specifically, the initiator is not particularly limited, but may be a photoinitiator that induces a polymerization reaction to polymerize monomer and oligomer molecules under light energy to form a polymer. For example, the photoinitiator is not particularly limited, but includes phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, 2,4,6-trimethylbenzoyl diphenylphosphine oxide, methylbenzoyl formate, 1-hydroxycyclohexylphenyl ketone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 2-benzyl-2-N,N-dimethylamino-1-(4-morpholinophenyl)-1-butanone, 1-hydroxycyclohexylphenyl ketone, benzophenone, 2,2-dimethoxy-2-phenyl acetophenone, bis(2,6-dimethoxybenzoyl-2,4,4-trimethylphenyl) phosphine oxide, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, It may include at least one selected from the group consisting of bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, 2-hydroxy-2-methyl-1-phenyl-1-propane, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, and 2,4,6-trimethylbenzoyldiphenylphosphine oxide. For example, the content of the initiator may be 0.1 to 1.5 parts by weight, 0.2 to 1.3 parts by weight, 0.3 to 1.0 parts by weight, 0.4 to 0.9 parts by weight, or 0.5 to 0.7 parts by weight with respect to 90 parts by weight of the base material. Core-shell rubber particles The core-shell rubber particles according to the present invention can prevent the viscosity of the adhesive composition from becoming excessively high and can implement impact resistance or compression resistance of the adhesive layer while maintaining the transparency of the adhesive layer at an appropriate level. Specifically, the core-shell rubber particles can sufficiently achieve compression resistance even under high compression ratio conditions. The core-shell rubber particle according to the present invention comprises a core portion and a shell portion on the core portion. Specifically, the shell portion may be disposed on part or all of the core portion, and more specifically, may be coated on part or all of the core portion. The shell portion according to the present invention is chemically bonded to the core portion. Specifically, since the shell portion is chemically bonded to the core portion, a sufficiently high compressive strength can be implemented even under high compression conditions with a compression ratio of 50% or more. If the core portion and the shell portion are not chemically bonded, a problem of the particles forming the core portion being destroyed under high compression ratio conditions may occur. For example, if the core portion and the shell portion in a core-shell rubber particle form a covalent bond with each other, it can be analyzed by an FT-IR (Fourier-transform infrared spectroscopy) analysis method. In some embodiments of the present invention, the particle diameter (D) of the core-shell rubber particles 50) may be 0.1 nm or more and 100 nm or less, specifically 0.1 nm or more, 1 nm or more, 10 nm or more, 20 nm or more, or 30 nm or more; and 35 nm or less, 40 nm or less, 50 nm or less, 60 nm or less, 70 nm or less, 80 nm or less, 90 nm or less, or 100 nm or less, and more specifically 0.1 to 100 nm, specifically 1 to 50 nm. According to some embodiments of the present invention, the particle size (D of the core-shell rubber particles 50 ) is adjusted to the above numerical range, thereby exhibiting excellent optical properties by exhibiting high total light transmittance, low haze and yellowness, and at the same time, high compressive strength can be realized under high compression conditions of a compression ratio of 50% or more. In some embodiments of the present invention, the content of the core-shell rubber particles may be 0.1 part by weight or more and 20 parts by weight or less, based on 90 parts by weight of the base material, specifically 0.1 part by weight or more, 0.5 part by weight or more, 1 part by weight or more, or more than 1 part by weight; and 2 parts by weight or less, 3 parts by weight or less, 4 parts by weight or less, less than 5 parts by weight, 5 parts by weight or less, 7 parts by weight or less, 10 parts by weight or less, 15 parts by weight or less, or 20 parts by weight or less, and more specifically 0.1 to 20 parts by weight, 0.5 to 10 parts by weight, 1 to 7 parts by weight, or more than 1 part by weight and less than 5 parts by weight. According to some embodiments of the present invention, when the content of the core-shell rubber particles is adjusted within the above numerical range, an effect of further increasing the compressive strength of the adhesive layer at a compression ratio of 50% or more can be implemented. The core part according to the present invention includes particles having an elastic modulus of 0.1 MPa or more under the conditions of 25°C, strain of 5.0%, and frequency of 10.0 Hz according to the DMA (Dynamic Mechanical Analysis) analysis method. Specifically, the elastic modulus of the core part may be 0.1 MPa or more, 0.2 MPa or more, 0.5 MPa or more, 0.8 MPa or more, or 1.0 MPa or more under the same analysis conditions described above; and 10 MPa or less, 15 MPa or less, or 20 MPa or less, and more specifically, 0.2 to 20 MPa, 0.5 to 15 MPa, 0.8 to 10 MPa, or 1 to 10 MPa. Here, if the elastic modulus of the core portion does not satisfy the above numerical range, a problem of significantly low compressive strength may occur due to destruction of silica particles under high compression ratio conditions due to lack of elasticity. Specifically, the core portion may include a structure of at least one of an acrylic compound, a diene compound, and a urethane compound, and more specifically, may include a structure of a diene compound, and more specifically, may include a structure of a butadiene compound (e.g., polybutadiene). In some examples, the acrylic compound may be a compound including at least one of a (meth)acryloyl group and an acryloyl group. In some examples, the diene compound is a compound different from the acrylic compound, may be a polymer polymerized with a monomer including a carbon-carbon double bond, and specifically may include at least one selected from the group consisting of polybutadiene, poly(1-vinylethylene), and poly(1-methylidene-2-phenyl-ethylene). In some examples, the urethane compound may include at least one urethane group in the molecule. The structures of the above-described acrylic compound, diene compound, and urethane compound may be chemically bonded (e.g., covalently bonded) with a material included in the shell portion. For example, the shell portion may include, but is not particularly limited to, a compound having a reactive functional group that chemically bonds with the base material, specifically, a compound having a reactive functional group including at least one carbon-carbon unsaturated bond, and more specifically, a compound having at least one of a vinyl group, an acrylate group, a methacrylate group, a dienyl group, and a styrene group. According to some embodiments of the present invention, since a compound having a reactive functional group that chemically bonds with the base material is included in the shell portion, a covalent bond can be formed with a monomer and / or oligomer included in the base material. Accordingly, the compression resistance of the adhesive layer can be further improved under a condition of a compression ratio of 50% or more. In some embodiments of the present invention, the shell portion may include a compound identical to at least one of the components forming the base material. According to some embodiments of the present invention, by including the shell portion as a compound identical to at least one of the components forming the base material, the compression resistance of the adhesive layer may be further improved under a condition where the compression ratio is 50% or higher. In some embodiments of the present invention, the weight ratio of the core portion and the shell portion may be 1:0.1 or more and 1:10 or less, specifically 1:0.1 or more, or 1:1 or more; and 1:2 or less, 1:3 or less, 1:4 or less, 1:5 or less, or 1:10 or less, and more specifically 1:0.1 to 1:5, 1:0.1 to 1:4, 1:0.1 to 1:2, or 1:0.1 to 1:1. According to some embodiments of the present invention, since the weight ratio of the core portion and the shell portion satisfies the numerical range, high total light transmittance, low haze and yellowness are exhibited, so that excellent optical properties are exhibited, and high compressive strength can be implemented under high compression conditions of a compression ratio of 50% or more. For example, the weight ratio of the core portion and the shell portion can be analyzed by any one method selected from the group consisting of TGA (Thermogravimetric Analyzers), UPLC (Ultra performance liquid chromatography), NMR (Nuclear Magnetic Resonance), and combinations thereof. In some embodiments of the present invention, the ratio of the particle size of the core part and the thickness of the shell part (the particle size of the core part: the thickness of the shell part) may be 1:0.1 or more and 1:1 or less. According to some embodiments of the present invention, since the ratio of the particle size of the core part and the thickness of the shell part satisfies the numerical range, high total light transmittance, low haze and yellowness are exhibited, so that excellent optical properties are exhibited, and high compressive strength can be implemented under high compression conditions of a compression ratio of 50% or more. Here, the particle size of the core part is the particle size (D) when the core part is in the form of particles. 50 ) can be defined as the average thickness of the portion surrounding part or all of the core portion. For example, the thickness of the shell portion can be 1 nm or less. For example, the particle diameter of the core portion and the thickness of the shell portion can be calculated by scanning a large amount of dispersed particles using SEM and / or TEM, and then calculating the average particle diameter and distribution, etc. using an auto detecting program, or can be analyzed by using a particle size analyzer to check the particle diameter when the core portion exists alone and measuring the particle diameters of the core-shell rubber particles and the difference in particle diameters between them. For example, the method for manufacturing the core-shell rubber particles is not particularly limited, but may be a method of synthesizing core particles by a sol-gel synthesis method, then substituting terminal groups of the core, and then inducing bonding with a single molecule, which is a material of the shell portion, through surface modification. Additives In some embodiments of the present invention, the adhesive composition may further include one or more additives selected from the group consisting of a UV stabilizer, a silane coupling agent, a surfactant, and a tackifier. The above UV stabilizer can compensate for the lowering of stability during the photopolymerization reaction. For example, the UV stabilizer is not particularly limited and may include a benzophenone-based compound, a benzotriazole-based compound; or a phosphorus or sulfur-containing antioxidant. Specifically, the sulfur-containing antioxidant may have a sulfur atom and may contain an ester group and a phenol group in the molecule, and specifically may include thiodiethylene bis[3-(3,5-di-tert-butyl-4-hydroxybenzyl) propionate]. In some embodiments of the present invention, the content of the UV stabilizer may be 0.1 to 1.0 parts by weight, 0.2 to 0.9 parts by weight, 0.3 to 0.8 parts by weight, or 0.4 to 0.5 parts by weight, based on 90 parts by weight of the base material. According to some embodiments of the present invention, when the content of the UV stabilizer satisfies the numerical range, the transparency of the adhesive layer can be expressed more excellently. The above silane coupling agent can further improve the bonding strength to the adhesive in the adhesive composition or the dispersion stability for the solid content. For example, the above silane coupling agent is not particularly limited, but vinyltrimethoxy(ethoxy)silane [trade name: KBM(

[0020] It may include at least one of 3-glycidoxypropyltrimethoxy(ethoxy)silane [trade name: KBM(E)-1003], 3-glycidoxypropyltrimethoxy(ethoxy)silane [trade name: KBM(E)-403], 3-methacryloxypropyltriethoxy(ethoxy)silane [trade name: KBM(E)-503], and 3-aminopropyltrimethoxy(ethoxy)silane. For example, the surfactant is added to control the surface tension of the adhesive composition, and includes low molecular weight acidic polyester, unsaturated polyamine amide salt [trade name: Anti terra U100 of BYK Chemie], high molecular weight alkylolamino amide [trade name: DISPERBYK-109], high molecular weight block copolymer solution [trade name: DISPERBYK-185], alkyl ammonium salt of high molecular weight copolymer [trade name: BYK-9076, 9077], acrylate copolymer [trade name: DISPERBYK-116], hydroxyl functional group carboxylic acid ester [trade name: DISPERBYK-108], polyether modified polydimethylsiloxane [trade name: BYK-302, 331, 332, 307, 333], aralkyl modified It may include at least one of polymethylalkylsiloxane [trade name: BYK-322, 323] and polyether-modified polydimethylsiloxane [trade name: BYK-377]. For example, the tackifier further enhances the adhesive performance of the adhesive composition and may include at least one of a rosin resin or a rosin derivative, a terpene resin or a terpene derivative, a hydrogenated C9 petroleum resin, a phenolic resin, a xylene resin, a chromine resin, a coumarone indene resin, and a ketone resin. The contents of each of the above-described silane coupling agent, surfactant, and tackifier are not particularly limited and may be appropriately modified depending on the purpose. Properties of the composition The viscosity of the adhesive composition according to the present invention is 25°C and 1,350 s -1In the adhesive composition, the viscosity is 50 cP or less, specifically 40 cP or less, 35 cP or less, 30 cP or less, 25 cP or less, 22 cP or less, 21.2 cP or less, 21.1 cP or less, 20.8 cP or less, or 20.1 cP or less; specifically 3 cP or more, 4 cP or more, or 5 cP or more; and may be less than any one of the plurality of upper limits. Specifically, when the viscosity of the adhesive composition satisfies the numerical range, processability and applicability can be facilitated. Accordingly, an advantage in application in an inkjet process can occur. If the viscosity of the adhesive composition does not satisfies the numerical range, the adhesive composition may not be properly discharged in a liquid state in the inkjet process due to its high viscosity. For example, the adhesive composition is not particularly limited to a printing method, but can be applied onto a substrate by an inkjet process. Here, since the inkjet process is a process in which a liquid adhesive composition is discharged, if the viscosity of the adhesive composition is excessively high, discharge may be difficult and a problem may occur in which it is difficult to implement a uniform adhesive layer. According to some embodiments of the present invention, by controlling the viscosity of the adhesive composition within the above numerical range, the advantage of application to the inkjet process can be further maximized. 2. Adhesive layer According to another aspect of the present invention, there is provided an adhesive layer comprising a polymer matrix including an acrylic resin; and core-shell rubber particles, wherein the adhesive layer has a compressive strength of 0.2 MPa or more and 1.5 MPa or less for a specimen having a thickness of 10 mm under conditions of a compression speed of 5 mm / min and a compression ratio of 50%, and is irradiated with light having a wavelength of 380 to 780 nm at 500 mW / cm. 2The present invention provides an adhesive layer having a yellow index of 4.80 or less after exposure to a dose of 250 hours. Specifically, the adhesive layer may be a cured adhesive composition according to some embodiments. Specifically, since the compressive strength and the yellow index of the adhesive layer simultaneously satisfy the numerical ranges described above, it is easy to achieve thin film formation, and at the same time, there is no need to introduce a separate shock-absorbing layer, so that deformation of the product can be minimized. The acrylic resin according to the present invention may be a polymer in which an acrylic monomer and an oligomer are polymerized by an initiator. Here, the polymer matrix may be a polymer including repeating units derived from a base material when analyzing an adhesive layer in which the adhesive composition is cured according to some embodiments. In some embodiments of the present invention, the shell portion of the core-shell rubber particle can be chemically bonded (e.g., covalently bonded) with the polymer matrix. Specifically, when there are multiple core-shell rubber particles, the shell portion of at least one of the particles can be chemically bonded with the polymer matrix. According to some embodiments of the present invention, when the shell portion is chemically bonded with the polymer matrix, the compression resistance or impact resistance can be further improved under a condition where the compression ratio is 50% or higher. For example, the distribution state of the core-shell rubber particles is not particularly limited and can be randomly dispersed within the polymer matrix. For example, the thickness of the adhesive layer is not particularly limited, but may vary depending on the type of device to which the adhesive layer is applied, and may specifically be 1 ㎛ to 1 mm or 1 ㎛ to 500 ㎛. In some embodiments of the present invention, the total transmittance (TT) of the adhesive layer may be 98% or more both initially and after 250 hours of exposure. Here, the exposure process comprises UV with a wavelength range of 380 to 780 nm at 500 mW / cm. 2 It can be performed under the conditions of the investigation amount. In some embodiments of the present invention, the haze of the adhesive layer can be 0.07% or less, 0.05% or less, 0.04% or less, or 0.01% or less at initial conditions. In some embodiments of the present invention, after an exposure time of 250 hours, the haze of the adhesive layer may be 0.20% or less, 0.18% or less, 0.16% or less, or 0.12% or less. Here, the exposure process conditions are as described above. In some embodiments of the present invention, the yellowness of the adhesive layer can be 0.55 or less, 0.53 or less, 0.51 or less, 0.49 or less, or 0.47 or less at initial conditions. In some embodiments of the present invention, after an exposure time of 250 hours, the yellowness of the adhesive layer may be 4.80 or less, 4.76 or less, 4.66 or less, 4.62 or less, or 4.52 or less. Here, the exposure process conditions are as described above. In some embodiments of the present invention, the compressive strength of the adhesive layer may be 0.058 MPa or more, 0.094 MPa or more, 0.150 MPa or more, 0.200 MPa or more, or 0.350 MPa or more under the conditions of a compression ratio of 25% and a compression speed of 5 mm / min. 3. Display device According to another aspect of the present invention, a display device comprising an adhesive layer according to some embodiments is provided. The display device according to the present invention is not particularly limited and may be an OLED, a flexible display device, or an optical film, etc. Hereinafter, an application example of an adhesive layer according to one embodiment of the present invention will be described with reference to FIG. 1. However, the technical idea of ​​the present invention is not limited to the display device illustrated in FIG. 1 and can be applied to various elements. Figure 1 is a cross-sectional view showing a display device according to one embodiment of the present invention. A display device (1000) according to the present invention may include a display panel (400), a first adhesive layer (AD1), a protective film (300), a buffer member (200), a support member (100), a second adhesive layer (AD2), a polarizing layer (500), a third adhesive layer (AD3), a window (600), and a protective layer (700). For example, the display device (1000) may include a support member (100), a buffer member (200) disposed on the support member (100), a protective film (300) disposed on the buffer member (200), a first adhesive layer (AD1) disposed on the protective film (300), a display panel (400) disposed on the first adhesive layer (AD1), a second adhesive layer (AD2) disposed on the display panel (400), a polarizing layer (500) disposed on the second adhesive layer (AD2), a third adhesive layer (AD3) disposed on the polarizing layer (500), a window (600) disposed on the third adhesive layer (AD3), and a protective layer (700) disposed on the window (600). The display panel (400) according to the present invention includes a plurality of pixels, each of which can emit light. Accordingly, the display panel (400) can display an image using the pixels. The protective film (300) according to the present invention can absorb external impact applied to the display panel (400). For example, the protective film (300) is not particularly limited and may include at least one of polyimide, polyethersulfone, polyacrylate, polyetherimide, polyethylenenaphthalate, polyphenylene sulfide, polyacrylate, polycarbonate, poly(arylene ethersulfone), and polyethylene terephthalate. The buffer member (200) according to the present invention can be arranged at the bottom of the protective film (300) to cushion external impact. For example, the buffer member (200) can be formed of a material that can contain air and provide cushioning, such as a cushion or sponge. In addition, the buffer member (200) can include an acrylic resin, polyurethane, thermoplastic polyurethane, latex, polyurethane foam, polystyrene foam, or the like. The support member (100) according to the present invention may be arranged below the buffer member (200). The support member (100) may support the display panel (400). In one embodiment, the support member (100) may be formed of a metal material, a non-metal material, etc. Examples of the metal material that may be used as the support member (100) may include invar, which is an alloy of nickel (Ni) and iron (Fe), stainless steel (SUS), titanium (Ti), copper (Cu), aluminum (Al), etc. Examples of the non-metal material that may be used as the support member (100) may include fiber reinforced plastic (FRP). The polarizing layer (500) according to the present invention can improve the color reproducibility of the display panel (400) by polarizing light incident on the display panel (400). The window (600) according to the present invention can protect the display panel (400). For example, the window (600) can include at least one of transparent polyimide, ultra-thin tempered glass, polyethylene terephthalate, polyether sulfone, polyacrylate, polyether imide, polyethylene naphthalate, polyphenylene sulfide, and polycarbonate. The protective layer (700) according to the present invention can protect the window (600). In one embodiment, the protective layer (700) can be formed of plastic. For example, the protective layer (700) can include transparent polyimide (colorless polyimide), polyethylene terephthalate, non-transparent polyimide, polyethersulfone, polyacrylate, polyetherimide, polyethylene naphthalate, polyphenylene sulfide, polycarbonate, and the like. At least one of the first to third adhesive layers (AD1, AD2, AD3) according to the present invention may include an adhesive layer according to some embodiments. When the adhesive layer according to some embodiments of the present invention is included in at least one of the first adhesive layer (AD1) and the third adhesive layer (AD3), the reliability and performance of the device can be further improved due to the excellent mechanical properties of the adhesive layer having high compressive strength even under high compression conditions. When the adhesive layer according to some embodiments of the present invention is included in the second adhesive layer (AD2), light incident on the display panel (400) can be transmitted well to the polarizing layer (500) without distortion due to the high transparency of the adhesive layer. Accordingly, the color reproducibility of the display device can be expressed more excellently. Hereinafter, embodiments of the present invention will be described in detail so that a person having ordinary skill in the art to which the present invention pertains can easily implement the present invention, but this is only an example, and the scope of the rights of the present invention is not limited by the following contents. [Manufacturing Example 1: Manufacturing of adhesive composition] Step of mixing monomers, oligomers, initiators and additives: A mixture was prepared by stirring the monomer, oligomer, initiator, and additive according to the composition in Table 1 below at 1,200 rpm for 50 minutes using a planetary mixer (Thicky Corporation). Step of adding particles to the above mixture and stirring: After adding the particles of Table 1 or 2 below to the above mixture, the mixture was stirred at 1,200 rpm for 30 minutes to prepare an adhesive composition. Composition unit: parts by weightExample 1Example 2Example 3Example 4Example 5Monomer2-EHA2020202020IDA20202020204-HBA303030303030Oligomerurethane-acrylate system2020202020PhotoinitiatorI8190.50.50.50.50.50.5AdditiveS10350.40.40.40.40.4Core-shell rubber particle0.51.02.05.010.01) 2-EHA: 2-Ethylhexyl acrylate2) IDA: Isodecyl acrylate3) 4-HBA: 4-hydroxybutyl acrylate4) Oligomer: Product name: Soltech (Korea) Urethane-acrylate oligomer [Urethane-acrylate oligomer (1,3-Diisocyanatomethylbenzenepolymer with hydroxy-terminated polybutadiene, 2-hydroxyethyl methacrylate-blocked) with a weight-average molecular weight of 5,000 g / mol and a glass transition temperature of -61.2℃]5) Photoinitiator: Phenylbis(2,4,6-trimethylbenzoyl)phosphineoxide6) Antioxidant (additive): Thiodiethylene bis[3-(3,5-di-tert-butyl-4-hydroxybenzyl) propionate]7) Core-shell rubber particle: Particle size (D 50 ) is 30 nm and has a core and shell weight ratio of 1:0.1. A butadiene-acrylate core-shell bead (core: butadiene; shell: acrylic chemically bonded to the core); wherein, according to the DMA (Dynamic Mechanical Analysis) method, under the conditions of 25°C, strain 5.0%, and frequency 10 Hz, the elastic modulus of the core is 0.1 MPa or more. Composition unit: weight parts Comparative example 1 Comparative example 2 Comparative example 3 Comparative example 4 Monomer 2-EHA 2020 2020 IDA 2020 2020 4-HBA 30 30 30 30 Oligomer urethane-acrylate system 2020 2020 Photoinitiator I8 19 0.5 0.5 0.5 0.5 Additive S 10 35 0.4 0.4 0.4 Particle (characteristics) 0 1.0 (Shell X) 1.0 (Core: Silica / Shell: Acrylic) 1.0 (Particle size (D 50 ) is 5 to 10㎛)1) 2-EHA: 2-Ethylhexyl acrylate2) IDA: Isodecyl acrylate3) 4-HBA: 4-hydroxybutyl acrylate4) Oligomer: Common name: 61363 (1,3-Diisocyanatomethylbenzenepolymer with hydroxy-terminated polybutadiene, 2-hydroxyethyl methacrylate-blocked)5) Photoinitiator: Phenylbis(2,4,6-trimethylbenzoyl)phosphineoxide6) Additive: Thiodiethylene bis[3-(3,5-di-tert-butyl-4-hydroxybenzyl) propionate]7) Particle: In the case of Comparative Example 2, the shell structure Butadiene-based rubber particles without a core; In the case of Comparative Example 3, the core is silica, and the shell is acrylic; wherein, according to the DMA (Dynamic Mechanical Analysis) method, under the conditions of 25°C, strain 5.0%, and frequency 10Hz, the elastic modulus of the silica is less than 0.1 MPa. In the case of Comparative Example 4, the particle size (D 50 ) is a butadiene-acrylate core-shell bead having a diameter of 5 to 10 μm (core part: butadiene-based; shell part: acrylic-based chemically bonded to the core part) [Experimental Example 1: Evaluation of optical properties and light resistance of adhesive layer] Each of the adhesive compositions of Examples 1 to 5 and Comparative Examples 1 to 4 was applied between two pieces of glass with a thickness of 10 to 500 ㎛, and then UV curing was performed (irradiation amount: 500 mW / cm) using exposure equipment (QUV equipment, UVB lamp) so that the curing rate was 99% or higher. 2 ) were performed to form each adhesive layer. Then, the total transmittance (TT), haze, and yellowness (YI) of the adhesive layer at 380 to 780 nm were measured using a haze meter (SH-7000). In the case of the reference, calibration was performed with LCD glass. Here, the light transmittance is an indicator of how much light of a given wavelength range is transmitted through the entire adhesive layer, and the unit is %. Haze is an indicator of the degree of cloudiness (opacity) caused by light scattered from the surface of a transparent adhesive layer sample, and the unit is %. Yellowness is an indicator of the degree of yellow tint caused by aging of the adhesive layer. Item Total Light Transmittance (380-750 nm): Unit = % Haze: Unit = % Yellowness (YI) Exposure Time (Hour) 0 (Initial) 250 hours 0 (Initial) 250 hours 0 (Initial) 250 hours Example 199.998. 50. 010. 120. 534. 76 Example 299.999. 60. 010. 160. 474. 62 Example 399.999. 10. 040. 180. 494. 52 Example 499.998. 40. 050. 16 0.514.66Example 599.898.00.070.200.554.80Comparative Example 199.998.90.020.160.434.54Comparative Example 299.898.80.030.150.444.83Comparative Example 391.490.10.410.560.787.63Comparative Example 478.675.43.413.670.885.11 Referring to Table 3 above, Examples 1 to 5 both showed a total light transmittance of 98% or more at the initial time and after 250 hours of exposure, and showed significantly lower effects in terms of haze value and change thereof, and yellowness and change thereof after UV irradiation compared to Comparative Examples 3 and 4. When comparing Example 2 and Comparative Example 3 in terms of the optical properties and light resistance of the adhesive layer according to the composition of the core portion in the rubber particles having a core-shell structure, Comparative Example 3, in which the core portion is composed of silica particles and the shell portion is composed of an acrylic material, exhibited problems of relatively low light transmittance, high haze, and high yellowness. On the other hand, Example 2, in which the core portion includes a butadiene-based compound and the shell portion is composed of an acrylic material, thereby chemically bonding the core and shell portions, exhibited high light transmittance and low haze and yellowness, confirming excellent optical properties and light resistance. Particle size (D) of rubber particles with core-shell structure 50 ) in terms of the optical properties and light resistance of the adhesive layer, Example 2 and Comparative Example 4 are compared, and the particle size (D) of the core-shell rubber particles 50 ) Example 2, which satisfies 1 to 50 nm, showed high total light transmittance, low haze and yellowness compared to Comparative Example 4, which had a large particle size of core-shell rubber particles, confirming excellent optical properties. [Experimental Example 2: Viscosity of adhesive composition] After setting the temperature of the constant temperature bath to 25℃, 7 g of the adhesive composition samples of Examples 1 to 5 and Comparative Examples 1 to 4 were placed in a viscosity measuring device (Viscometer of Cannon Fenske) and fixed in the constant temperature bath. After a stabilization stage of 10 minutes or more, the time for the sample to reach the upper line of the viscometer from the lower line was measured in seconds, and the viscosity of the adhesive composition was calculated according to the following Equation 1 (shear rate = 1,350 s -1 ). [Formula 1] Viscosity at 25℃ (cP) = Viscometer constant (correction constant) X time (sec) X specific gravity 25℃ and 1,350 s -1 Viscosity (cP) of the adhesive composition in Example 121.1 Example 220.8 Example 320.1 Example 421.2 Example 522.0 Comparative Example 120.7 Comparative Example 224.2 Comparative Example 335.4 Comparative Example 452.4 Referring to Table 4 above, it was confirmed that the viscosity of the adhesive compositions according to Examples 1 to 5 was lower than that of Comparative Examples 2 to 4. Meanwhile, in the case of Comparative Example 1, unlike other specimens, particles were not used, resulting in low viscosity. [Experimental Example 3: Impact resistance evaluation of adhesive layer] The adhesive compositions of Examples 1 to 5 and Comparative Examples 1 to 4 were filled into a silicone mold (25 mm x 25 mm x 10 mm) to a thickness of 2 mm, and then a UV curing (curing rate of 50% or more) process was performed. This process was repeated, and the coating and curing processes were repeated by laminating the adhesive composition in layers at 2 mm each time until the thickness became 10 mm. Thereafter, after the complete UV curing process (curing rate of 99% or more), the compressive strength was measured under conditions of 25% and 50% compression rates using a UTM (Universal Testing Machine, Instron 5566). At this time, the compression speed was set to 5 mm / min and the evaluation temperature was set to room temperature. Compressive strength at a compression ratio of 25% (MPa)Compressive strength at a compression ratio of 50% (MPa)Example 10.0580.223Example 20.0940.428Example 30.1651.326Example 40.2130.834Example 50.3550.892Comparative Example 10.0490.192Comparative Example 20.0890.385Comparative Example 30.1680.231Comparative Example 40.2430.234 When comparing Examples 1 to 5 in terms of compressive strength according to the content of core-shell rubber particles in Table 5 above, it was confirmed that as the content of core-shell rubber particles increased, the compressive strength of the adhesive layer at a compression ratio of 25% increased, and when the content of core-shell rubber particles was more than 1 part by weight and less than 5 parts by weight with respect to the total sum of 90 parts by weight of monomer and oligomer, the compressive strength of the adhesive layer at a compression ratio of 50% further increased. In the case of Comparative Example 1, which did not include core-shell rubber particles, sufficient compressive strength was not achieved compared to Examples 1 to 5. In the case of Comparative Example 2, which included particles having only a core portion and no shell portion, the particles showed lower compressive strength than Example 2 because they were not reactive with the acrylic resin included in the polymer matrix. In the case of Comparative Example 3, in which the core part is composed of silica particles, a high compressive strength was exhibited at an initial compression ratio of 25% compared to Example 2, but there was a problem in that the compressive strength was significantly low at a compression ratio of 50% due to destruction of the silica particles due to the lack of elasticity due to the characteristics of silica. On the other hand, Example 2 exhibited a high compressive strength at a compression ratio of 50% due to its excellent elasticity by including a butadiene-based compound as the core part. Entry (D) 50 ) In the case of Comparative Example 4 containing core-shell rubber particles having a particle size of 5 to 10 μm, it exhibited a high compressive strength at an initial compression ratio of 25% compared to Example 2, but showed a significantly lower compressive strength due to particle destruction at a compression ratio of 50%. On the other hand, Example 2 exhibited a particle size of 5 to 10 μm, but showed a high compressive strength at an initial compression ratio of 25% compared to Example 2. 50 ) satisfied 1 to 50 nm, exhibiting high compressive strength at a compression ratio of 50%. [Manufacturing Example 2: Manufacturing of adhesive composition according to weight ratio of monomer and oligomer] An adhesive composition was prepared in the same manner as in Example 5, but the weight ratio of the monomer and the oligomer was adjusted to the weight ratio described in Table 6 below. Composition unit: parts by weightExample 6Example 7Example 8Example 9Example 10Comparative example 5Monomer2-EHA222017151310IDA2220171513104-HBA414031302420Oligomer (acrylic polymer)Urethane-acrylate system51025304050PhotoinitiatorI8190.50.50.50.50.50.50.5AdditiveS10350.40.40.40.40.40.40.4Core-shell rubber particle1.01.01.01.01.01.0Weight ratio of oligomer and monomer (oligomer:monomer)1:171:81:2.61:21:1.251:0.81) 2-EHA: 2-Ethylhexyl acrylate2) IDA: Isodecyl acrylate3) 4-HBA: 4-hydroxybutyl acrylate4) Oligomer: Common name: 61363 (1,3-Diisocyanatomethylbenzenepolymer with hydroxy-terminated polybutadiene, 2-hydroxyethyl methacrylate-blocked)5) Photoinitiator: Phenylbis(2,4,6-trimethylbenzoyl)phosphineoxide6) Additive: Thiodiethylene bis[3-(3,5-di-tert-butyl-4-hydroxybenzyl) propionate]7) Core-shell rubber particle: Particle size (D 50 ) is 1 to 50 nm, and the weight ratio of the core and the shell is 1: 0.1. Butadiene-acrylate core-shell bead (core: butadiene type; shell: acrylic type chemically bonded to the core) [Experimental Example 4: Viscosity of adhesive composition] The viscosity of the adhesive composition was measured using the same method as in Experimental Example 2 above, and the results are shown in Table 7 below. Weight ratio of oligomer and monomer (oligomer:monomer) 25℃ and 1,350 s -1Viscosity (cP) of the adhesive composition in Example 61: 177.5 Example 71: 812.1 Example 81: 2.628.9 Example 91: 234.0 Example 101: 1.2541.8 Comparative Example 51: 0.860.2 Referring to Table 7 above, in the case of Comparative Example 5 where the weight ratio of the oligomer and the acrylic monomer was 1:0.8, it was confirmed that the viscosity of the adhesive composition exceeded 50 cP, making it difficult to discharge in the inkjet process. On the other hand, Examples 6 to 10 satisfied the weight ratio of the oligomer and the acrylic monomer being 1:1 to 1:17, thereby confirming that the viscosity of the adhesive composition corresponds to 50 cP or less, and thus, it was confirmed that the discharge was easy in the inkjet process. [Manufacturing Example 3: Manufacturing of adhesive composition having different types of compounds included in the shell] An adhesive composition was prepared in the same manner as in Example 5, but the type of core-shell rubber particles was changed to the types described in Table 8 below. [Experimental Example 5: Viscosity of adhesive composition] The viscosity of the adhesive composition was measured using the same method as in Experimental Example 2 above, and the results are shown in Table 8 below. Shell material of core-shell rubber particles at 25℃ and 1,350 s -1 Viscosity (cP) of the adhesive composition in Example 5 HDDA (1,6-Hexanediol diacrylate) 22.0 Comparative Example 6 Hydrophilic surfactant of the following chemical formula 3 23,450 Comparative Example 7 Epoxy silane coupling agent compound (3-Glycidoxypropyltrimethoxysilane, GPTMS) 75.8 [Chemical Formula 3] In the above chemical formula 3, n is 10. Referring to Table 8 above, it was confirmed that the viscosity of the adhesive composition greatly differs depending on the material of the shell portion in the core-shell rubber particles. In the case of Comparative Examples 6 and 7, where a surfactant or coupling agent compound was simply selected as the material of the shell portion, it was confirmed that the viscosity of the adhesive composition excessively increased. Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concept of the present invention defined in the following claims also fall within the scope of the present invention. [Explanation of symbols] 1000: Display device AD1: First adhesive layer AD2: Second adhesive layer AD3: Third adhesive layer

Claims

1. Base material containing acrylic monomer and oligomer; Initiator; and Core-shell rubber particles comprising a core portion and a shell portion; According to the DMA (Dynamic Mechanical Analysis) method, under the conditions of 25℃, strain 5.0%, and frequency 10.0 Hz, the elastic modulus of the core part is 0.1 MPa or more, The above shell portion is chemically bonded to the core portion, 25℃ and 1,350 s -1 In which the viscosity is less than 50 cP, Adhesive composition.

2. In paragraph 1, The above acrylic monomer is, Comprising at least one compound represented by the following chemical formulas 1 and 2, Adhesive composition: [Chemical Formula 1] [Chemical formula 2] In the above chemical formulas 1 and 2, R1 and R2 are each independently hydrogen; deuterium; an alkyl group having 1 to 20 carbon atoms, wherein at least one hydrogen atom is substituted or unsubstituted with a hydroxy group; or a substituted or unsubstituted aromatic ring group having 3 to 20 carbon atoms.

3. In paragraph 1, The above oligomer is, Containing at least one of a structure derived from an acrylic group, a urethane group, an epoxy group, a siloxane group, and an ester group, Adhesive composition.

4. In paragraph 1, The weight average molecular weight of the above oligomer is 2,000 g / mol or more and 15,000 g / mol or less. Adhesive composition.

5. In paragraph 1, The glass transition temperature of the above oligomer is -80℃ or higher and 20℃ or lower. Adhesive composition.

6. In paragraph 1, The weight ratio of the above oligomer and the above acrylic monomer is 1:1 or more and 1:17 or less. Adhesive composition.

7. In paragraph 1, The particle size (D) of the above core-shell rubber particles 50 ) is 0.1 nm or more and 100 nm or less, Adhesive composition.

8. In paragraph 1, The content of the above core-shell rubber particles is 0.1 to 20 parts by weight based on 90 parts by weight of the above base material, Adhesive composition.

9. In paragraph 1, The content of the above core-shell rubber particles is More than 1 part by weight and less than 5 parts by weight based on 90 parts by weight of the above base material, Adhesive composition.

10. In paragraph 1, The above core part, Containing at least one structure among an acrylic compound, a diene compound, and a urethane compound, The above shell part, Comprising a structure of a compound having a reactive functional group that chemically bonds with the base material; Adhesive composition.

11. In paragraph 10, The above reactive functional group comprises a carbon-carbon unsaturated bond, Adhesive composition.

12. In paragraph 1, The weight ratio of the core portion and the shell portion is 1:0.1 or more and 1:10 or less. Adhesive composition.

13. In paragraph 1, The ratio of the particle size of the core portion to the thickness of the shell portion is 1:0.1 or more and 1:1 or less. Adhesive composition.

14. A polymer matrix comprising an acrylic resin; and An adhesive layer comprising core-shell rubber particles; The above adhesive layer is, Under the conditions of a compression speed of 5 mm / min and a compression ratio of 50%, the compressive strength is 0.2 MPa or more and 1.5 MPa or less for a specimen with a thickness of 10 mm. Light with a wavelength of 380 to 780 nm at 500 mW / cm 2 After exposure for 250 hours at a dose of , the yellow index is 4.80 or less. Adhesive layer.

15. A display device comprising an adhesive layer according to Article 14.

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