Adhesive composition, adhesive sheet and display comprising the same

Abstract

The present invention relates to an adhesive composition, an adhesive sheet manufactured using the same, and a display comprising the same, the adhesive composition comprising an acrylic copolymer polymerized by containing a compound represented by Chemical Formula 1, thereby being environmentally friendly and excellent in durability and bending characteristics, and having excellent reliability even in high-temperature and high-humidity environments. In chemical formula 1, R1 is hydrogen or methyl, and R2 is a biomass-derived hydrocarbon group having 1-9 carbon atoms. Chemical formula 1

Description

TECHNICAL FIELD

[0001] The present application relates to an adhesive composition, an adhesive sheet manufactured using the same, and a display including the same. BACKGROUND

[0002] In the display industry, in order to mount a touch panel or a touch screen or to obtain high brightness and high transmittance, an optically transparent pressure-sensitive adhesive is mostly used.

[0003] An adhesive used for attaching a transparent film or ultra thin glass (UTG) on a touch screen or a touch panel used in the above-described display industry requires adhesion to various substrates, and at the same time, durability to suppress the occurrence of curling or bubbles or the like even when exposed to severe conditions such as high temperature, high humidity conditions, and the like.

[0004] The above-described adhesive is manufactured by including petrochemical products derived from a separation and refining process of petroleum, and according to international agreements for strict control of greenhouse gas emissions, such petrochemical products can cause a huge environmental cost.

[0005] Therefore, development of eco-friendly materials that can replace existing petrochemical products is in progress.

[0006] In particular, in fields such as electronic materials that require precise dimensional stability, durability and reliability must be ensured so that the occurrence of bending phenomena due to curling, bubbles, or peeling can be prevented under severe conditions such as high temperature, high humidity, and the like as above.

[0007] Further, according to European environmental regulations, there is a need to develop an adhesive composition that applies eco-friendly materials and has excellent durability and bending properties.

[0008] Korean Registered Patent No. 10-1535564 discloses a starch-based polymer particle emulsion for an adhesive, which provides an adhesive water-based emulsion including a starch-based polymer having a core-shell structure and water, thereby being eco-friendly and having excellent initial adhesion, peeling adhesion strength with a material to be adhered, and re-peeling properties, but still has a problem in that the occurrence of bending, bubbles, or peeling cannot be sufficiently suppressed under severe conditions such as high temperature, high humidity, and the like.

[0009] PRIOR ART DOCUMENT

[0010] PATENT DOCUMENT

[0011] Korean Registered Patent No. 10-1535564 SUMMARY

[0012] PROBLEMS TO BE SOLVED BY THE INVENTION

[0013] The present application has been made to solve the above-described conventional problems, and aims to provide an adhesive composition which uses an environmentally friendly material and is excellent in durability and bending properties.

[0014] In addition, the present application aims to provide an adhesive sheet which is environmentally friendly and excellent in reliability and bending properties in a high-temperature and high-humidity environment, and a display including the same.

[0015] However, the problems to be solved by the present application are not limited to the above-mentioned problems, and other problems not mentioned can be clearly understood by those skilled in the art from the following description.

[0016] Method of solving the problems

[0017] To achieve the above object, the present application provides an adhesive composition including an acrylic copolymer polymerized by polymerizing a compound represented by the following Chemical Formula 1.

[0018] [Chemical Formula 1]

[0019]

[0020] In the above Chemical Formula 1, R1 is hydrogen or a methyl group, and R2 is a biomass-derived hydrocarbon group having 1 to 9 carbon atoms.

[0021] The compound represented by the above Chemical Formula 1 can include one or more selected from the group consisting of compounds represented by the following Chemical Formulas 2 and 3.

[0022] [Chemical Formula 2]

[0023]

[0024] [Chemical Formula 3]

[0025]

[0026] The compound represented by the above Chemical Formula 1 can include both the compound represented by the above Chemical Formula 2 and the compound represented by Chemical Formula 3.

[0027] At this time, the compound represented by the above Chemical Formula 2 and the compound represented by Chemical Formula 3 can be included in a ratio of 1:10 to 10:1.

[0028] The content of the compound represented by the above Chemical Formula 1 can be 30 to 80% by weight, with respect to the total weight of monomers used in the polymerization of the above acrylic copolymer.

[0029] The adhesive composition of the present application can further include a compound represented by the following Chemical Formula 4.

[0030] [Chemical Formula 4]

[0031]

[0032] In the above Chemical Formula 4, each of the above Ra to Rc is independently a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 30 carbon atoms, a substituted or unsubstituted heterocycloalkyl group having 3 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted arylene group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroarylene group having 6 to 30 carbon atoms, and any two of the above Ra to Rc are combined together to form a ring system.

[0033] The compound represented by the above Chemical Formula 4 can include one or more selected from the group consisting of compounds represented by the following Chemical Formulas 5 and 6.

[0034] [Chemical Formula 5]

[0035]

[0036] [Chemical Formula 6]

[0037]

[0038] The content of the compound represented by the above Chemical Formula 4 can be 1.0 to 10 parts by weight with respect to 100 parts by weight of the acrylic copolymer.

[0039] The adhesive composition of the present application can further include one or more silane coupling agents selected from the group consisting of compounds represented by the following Chemical Formulas 7 and 8.

[0040] [Chemical Formula 7]

[0041]

[0042] In the above Chemical Formula 7, R3 is an alkyl group having 1 to 12 carbon atoms, each of R4 is independently a divalent aliphatic hydrocarbon group having 1 to 30 carbon atoms, and each of R5 to R7 is independently hydrogen, an alkyl group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, an alkynyl group having 2 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms.

[0043] [Chemical Formula 8]

[0044]

[0045] In the above Chemical Formula 8, R8 is an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms, R9 is a divalent aliphatic hydrocarbon group having 1 to 30 carbon atoms, and R 10 ~R 12each independently is hydrogen, an alkyl group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, an alkynyl group having 2 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms.

[0046] The content of the above silane coupling agent can be 0.01 to 3 parts by weight, relative to 100 parts by weight of the acrylic copolymer.

[0047] The biomass degree of the adhesive sheet formed from the above adhesive composition, calculated according to ASTM D6866 and according to the following Formula 1, can be 30% or more.

[0048] [Formula 1]

[0049] Biomass degree (%) = number of carbon atoms derived from biomass / total number of carbon atoms x 100

[0050] The above adhesive composition can further include one or more selected from the group consisting of a crosslinking agent, an antistatic agent, a surfactant, an adhesion promoter, and a coagulation inhibitor.

[0051] In addition, the present application relates to an adhesive sheet including the above adhesive composition.

[0052] In addition, the present application relates to a display including the above adhesive sheet.

[0053] Effects of the Invention

[0054] The present application can provide an adhesive composition that is environmentally friendly and has excellent durability and bending properties, by including an acrylic copolymer in which monomers derived from biomass are mixed and polymerized.

[0055] In addition, the present application can provide an adhesive sheet that uses environmentally friendly materials and has excellent reliability and bending properties in a high-temperature and high-humidity environment, and a display including the same. DETAILED DESCRIPTION

[0056] The present application relates to an adhesive composition, an adhesive sheet, and a display, the above adhesive composition including an acrylic copolymer in which monomers derived from biomass are polymerized by mixing, so as to satisfy a biomass degree of 30% or more measured according to ASTM D6866, while having excellent durability and excellent reliability and bending properties without generating curling or bubbles in a high-temperature and high-humidity environment.

[0057] Biomass is a general term for biological organisms such as plants and animals that feed on plants and microorganisms that synthesize organic matter using solar energy, and includes secondary products and waste derived from these biological organisms. The above compound derived from biomass includes a radioactive carbon isotope ( 14 C) that exists only in natural source materials, and does not include a radioactive carbon isotope ( 14The petroleum-derived compounds of C) are distinguished.

[0058] To this end, the biomass degree of the adhesive sheet formed from the adhesive composition can be calculated by measuring the concentration of the radioactive carbon isotope (14C) contained in the adhesive composition, specifically, can be measured in accordance with ASTM D6866. 14 C) are distinguished.

[0059] The biomass degree of the adhesive composition and the adhesive sheet comprising the same of the present application can be calculated according to the following Formula 1 by distinguishing the carbon of the biomass origin and the carbon of the fossil fuel origin through the above-described ASTM D6866, and thus the thus-calculated biomass degree can be 30% or more.

[0060] [Formula 1]

[0061] Biomass degree (%) = Number of carbon atoms of biomass origin / Total number of carbon atoms x 100

[0062] The present application can more accurately and easily confirm the biomass degree since the biomass degree is calculated according to the above-described Formula 1.

[0063] Hereinafter, the present application will be described in more detail. However, the terms used in the present specification are intended to describe the embodiments and are not intended to limit the present application. In the present specification, the meaning of the adhesive sheet can include an adhesive layer as well as an adhesive film.

[0064] <Adhesive composition>

[0065] The adhesive composition of the present application comprises an acrylic copolymer polymerized by containing a compound of Chemical Formula 1 which is a monomer of biomass origin. Also, in order to impart adhesiveness, a silane coupling agent having a compound represented by Chemical Formula 4 and / or triethoxysilane can be further included. Optionally, one or more selected from the group consisting of a crosslinking agent, a surfactant, a adhesion promoter, and a coagulation inhibitor can be further included.

[0066] Acrylic copolymer

[0067] The acrylic copolymer included in the adhesive composition of the present application is polymerized by containing a monomer of biomass origin, and is characterized by including an acrylic copolymer polymerized by containing a compound represented by the following Chemical Formula 1.

[0068] [Chemical Formula 1]

[0069]

[0070] In the above Chemical Formula 1, R1 is hydrogen or methyl, and R2 is a hydrocarbon group of biomass origin having 1 to 9 carbon atoms.

[0071] The above-mentioned hydrocarbon group derived from biomass is not particularly limited as long as it is derived from biomass, i.e., a biological organism such as a plant and an animal that eats the plant, a microorganism, etc., which synthesizes an organic substance by receiving solar energy, and can be obtained inexpensively and easily by alcoholizing or esterifying a saturated fatty acid or an unsaturated fatty acid collected from the biological organism.

[0072] The hydrocarbon group derived from biomass of the present application can include a saturated or unsaturated hydrocarbon group, and can include a chain or alicyclic hydrocarbon group.

[0073] As the above-mentioned saturated or unsaturated chain hydrocarbon group, it can be linear or branched, and examples include an alkyl group, an alkenyl group, etc.

[0074] As the above-mentioned saturated or unsaturated alicyclic hydrocarbon group, it includes a monocyclic or polycyclic alicyclic hydrocarbon group, and examples include a cycloalkyl group, a cycloalkenyl group containing a double bond, an adamantyl group, etc.

[0075] In addition, the above-mentioned hydrocarbon group can include a combination of a saturated or unsaturated chain or alicyclic hydrocarbon group. That is, examples include a combination of an alkyl group and an alkenyl group, a combination of an alkyl group and a cycloalkyl group, a combination of an alkyl group and a cycloalkenyl group, a combination of a cycloalkyl group and a cycloalkenyl group, etc.

[0076] The above-mentioned compound represented by Chemical Formula 1 can more specifically include one or more selected from the group consisting of compounds represented by Chemical Formulas 2 and 3.

[0077] [Chemical Formula 2]

[0078]

[0079] [Chemical Formula 3]

[0080]

[0081] Further, the above-mentioned compound represented by Chemical Formula 1 can include both the compound represented by Chemical Formula 2 and the compound represented by Chemical Formula 3. In this case, flexibility is increased, and the bending properties are more advantageous.

[0082] At this time, the compound represented by Chemical Formula 2 and the compound represented by Chemical Formula 3 can be included in a ratio of 1:10 to 10:1, and more preferably, in a ratio of 1:5 to 5:1. When they are included in the above-mentioned ratio, it is advantageous in terms of improving the bending properties.

[0083] The content of the compound represented by Chemical Formula 1 can be 30 to 80% by weight, relative to the total weight of monomers used in the polymerization of the acrylic copolymer. When the content range is satisfied, the acrylic copolymer has the advantage of excellent reliability while achieving the target biobased content without reducing the durability and bending properties under high temperature and high humidity.

[0084] The acrylic copolymer of the present application can be formed by further including one or more polymers selected from the group consisting of (meth)acrylic acid alkyl ester, carboxyl group-containing monomer, and hydroxyl group-containing monomer, in addition to the compound represented by Chemical Formula 1.

[0085] The (meth)acrylic acid alkyl ester is not particularly limited, and the "(meth)acrylic acid ester" refers to both acrylate and methacrylate.

[0086] Specific examples of the (meth)acrylic acid alkyl ester include (meth)acrylic acid methyl ester, (meth)acrylic acid ethyl ester, (meth)acrylic acid n-propyl ester, (meth)acrylic acid isopropyl ester, (meth)acrylic acid n-butyl ester, (meth)acrylic acid sec-butyl ester, (meth)acrylic acid t-butyl ester, (meth)acrylic acid isobutyl ester, (meth)acrylic acid pentyl ester, (meth)acrylic acid hexyl ester, (meth)acrylic acid 2-ethylhexyl ester, (meth)acrylic acid n-octyl ester, (meth)acrylic acid isooctyl ester, (meth)acrylic acid n-nonyl ester, (meth)acrylic acid isononyl ester, (meth)acrylic acid n-decyl ester, (meth)acrylic acid isodecyl ester, (meth)acrylic acid n-dodecyl ester, (meth)acrylic acid n-tridecyl ester, (meth)acrylic acid n-tetradecyl ester, (meth)acrylic acid phenoxyethyl ester, and the like.

[0087] The content of the (meth)acrylic acid alkyl ester can be 10 to 70% by weight, relative to the total weight of monomers used in the polymerization of the acrylic copolymer. When the content range is satisfied, it is preferable in terms of improving adhesion and durability.

[0088] The carboxyl group-containing monomer can be, for example, monobasic acids such as (meth)acrylic acid, crotonic acid, isocrotonic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, and the like; dibasic acids such as maleic acid, itaconic acid, fumaric acid, and monoalkyl esters thereof; compounds such as succinic anhydride ring-opening adducts of (meth)acrylic acid 2-hydroxyalkyl esters having 2 to 3 carbon atoms in the alkyl group, succinic anhydride ring-opening adducts of hydroxyalkylene glycol (meth)acrylates having 2 to 4 carbon atoms in the alkylene group, caprolactone adducts of (meth)acrylic acid 2-hydroxyalkyl esters having 2 to 3 carbon atoms in the alkyl group, and the like, of which (meth)acrylic acid is preferable.

[0089] The content of the carboxyl group-containing monomer can be 0.01 to 10% by weight, relative to the total weight of the monomers used in the polymerization of the above-described acrylic copolymer. When the content is within the above-described range, it is preferable in terms of cohesiveness and durability.

[0090] The hydroxyl group-containing monomer can be exemplified by 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, 12-hydroxylauryl (meth)acrylate, (4-hydroxymethylcyclohexyl)methyl acrylate, N-methylol (meth)acrylamide, vinyl alcohol, allyl alcohol, 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, diethylene glycol monovinyl ether, 2-acryloyloxyethyl-2-hydroxyethyl phthalate, and the like.

[0091] In addition, the acrylic monomer of the present application can be polymerized by further including a general acrylic monomer in addition to the compound represented by the above-described Chemical Formula 1, the alkyl (meth)acrylate, the carboxyl group-containing monomer, and the hydroxyl group-containing monomer, and the general acrylic monomer can include one or more selected from the group consisting of a sulfonic acid group-containing monomer, a phosphoric acid group-containing monomer, a cyano group-containing monomer, a vinyl ester monomer, an aromatic vinyl monomer, an acid anhydride group-containing monomer, an amide group-containing monomer, an amino group-containing monomer, an imide group-containing monomer, an epoxy group-containing monomer, and an ether group-containing monomer.

[0092] The sulfonic acid group-containing monomer can be exemplified by styrene sulfonic acid, allyl sulfonic acid, 2-(meth)acrylamido-2-methylpropane sulfonic acid, (meth)acrylamidopropyl sulfonic acid, (meth)acrylate sulfopropyl ester, (meth)acryloyloxy naphthalene sulfonic acid, sodium vinyl sulfonate, and the like.

[0093] The phosphoric acid group-containing monomer can be exemplified by 2-hydroxyethyl acryloyl phosphate, and the cyano group-containing monomer can be exemplified by (meth)acrylonitrile, and the like.

[0094] The vinyl ester monomer can be exemplified by vinyl acetate, vinyl propionate, vinyl laurate, and the like, and the aromatic vinyl monomer can be exemplified by styrene, chlorostyrene, chloromethylstyrene, α-methylstyrene, other substituted styrenes, and the like.

[0095] The acid anhydride group-containing monomer can be exemplified by maleic anhydride, itaconic anhydride, and the like.

[0096] The above-mentioned amide group-containing monomer can be exemplified by (meth)acrylamide, N-isopropyl acrylamide, N-tert-butyl acrylamide, 3-hydroxypropyl (meth)acrylamide, 4-hydroxybutyl (meth)acrylamide, 6-hydroxyhexyl (meth)acrylamide, 8-hydroxyoctyl (meth)acrylamide, 2-hydroxyethylhexyl (meth)acrylamide, and the like.

[0097] The above-mentioned amino group-containing monomer can be exemplified by N,N-(dimethylamino)ethyl (meth)acrylate, N,N-(diethylamino)ethyl (meth)acrylate, N,N-(dimethylamino)propyl (meth)acrylate, and the like, and the above-mentioned imide group-containing monomer can be exemplified by cyclohexylmaleimide, isopropylmaleimide, and the like.

[0098] The above-mentioned epoxy group-containing monomer can be exemplified by glycidyl (meth)acrylate, methyl glycidyl (meth)acrylate, and the like, and the above-mentioned ether group-containing monomer can be exemplified by 3-methoxybutyl (meth)acrylate, 2-methoxyethyl (meth)acrylate, 3-methoxypropyl (meth)acrylate, 2-methoxybutyl (meth)acrylate, methoxy polyethylene glycol acrylate having an addition mole number of ethylene oxide of 1 to 15, ethoxy-diethylene glycol (meth)acrylate, ethyl carbitol (meth)acrylate, and the like.

[0099] In addition to the above-mentioned monomers, the above-mentioned acrylic copolymer can further contain other monomers generally used in the technical field to which the present application pertains, within a range not lowering the adhesion. For example, the content thereof can be 10% by weight or less, relative to the total weight of the monomers used in the polymerization of the acrylic copolymer.

[0100] The weight average molecular weight (polystyrene conversion; Mw) of the above-mentioned acrylic copolymer, as measured by gel permeation chromatography (GPC), can be 500,000 to 2,000,000, and more preferably, 700,000 to 1,700,000. In the case where the weight average molecular weight of the acrylic copolymer is lower than 500,000, the intra-chain structure in the structure of the adhesive film after the ultraviolet polymerization and curing is simple and short, and thus is disadvantageous in terms of reliability in that air bubbles and the like are generated, and durability can be lowered due to discoloration and the like. In the case where the weight average molecular weight of the acrylic copolymer is higher than 2,000,000, the viscosity of the adhesive resin composition is excessively high in the manufacture of the adhesive film, and thus a large amount of monomers needs to be diluted to achieve a proper viscosity required for the manufacture, and thus high energy can be required in the ultraviolet polymerization and curing, or unreacted monomers can remain.

[0101] The method for producing the above-described acrylic copolymer is not particularly limited. For example, a method such as bulk polymerization, solution polymerization, emulsion polymerization, suspension polymerization, UV polymerization, and the like, which is generally used in the technical field to which the present application pertains, can be used, and preferably, solution polymerization or UV polymerization can be used.

[0102] Compound represented by chemical formula 4

[0103] The adhesive composition of the present application can further include a compound represented by Chemical Formula 4.

[0104] [Chemical Formula 4]

[0105]

[0106] Each of the above-described Ra to Rc is independently a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 30 carbon atoms, a substituted or unsubstituted heterocycloalkyl group having 3 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted arylene group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroarylene group having 6 to 30 carbon atoms, and any two of the above-described Ra to Rc can be combined together to form a ring system.

[0107] The above-described "substituted" means that at least one hydrogen atom of a chemical structure is substituted with another terminal substituent, and exemplary substituents that can exist at the "substituted" position include a nitro group (-NO2), a cyano group (-CN), a hydroxyl group (-OH), an oxo group (=O), an amino group (-NH2), an alkylamino group having 1 to 6 carbon atoms, a formyl group (-C(=O)H), an alkyl ester group (-C(=O)O-alkyl or -OC(=O)-alkyl) having 2 to 6 carbon atoms, an aryl ester group (-C(=O)O-aryl or -OC(=O)-aryl) having 7 to 13 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, a cycloalkenyl group having 5 to 18 carbon atoms, a heterocycloalkenyl group having 2 to 18 carbon atoms, an aryl group having 6 to 12 carbon atoms having at least one aromatic ring, an aralkyl group having 7 to 19 carbon atoms having 1 to 3 independent rings or fused rings and 6 to 18 ring carbon atoms, an aralkoxy group having 1 to 3 independent rings or fused rings and 6 to 18 ring carbon atoms, an alkylaryl group having 7 to 12 carbon atoms, a heterocycloalkyl group having 3 to 12 carbon atoms, or a heteroaryl group having 3 to 12 carbon atoms, but is not limited thereto.

[0108] Any two of the above-described Ra to Rc can be optionally linked together to form a substituted or unsubstituted ring system, and can be linked by a single bond or a 2-valent linking group.

[0109] The above-described ring system includes an aliphatic or aromatic ring, and can be in a form in which a plurality of rings are linked.

[0110] The compound represented by Chemical Formula 4 above can include one or more selected from the group consisting of compounds represented by Chemical Formulas 5 and 6 below, for example.

[0111] [Chemical Formula 5]

[0112]

[0113] [Chemical Formula 6]

[0114]

[0115] The adhesive composition of the present application further includes the compound represented by Chemical Formula 4 above, thereby improving the adhesive force.

[0116] The compound represented by Chemical Formula 4 above is mixed with the acrylic copolymer above to provide a chain extension effect, thereby improving the elasticity and the adhesive force, and further improving the bending properties.

[0117] In particular, in the case where a crosslinking agent is mixed in order to improve the durability of the acrylic copolymer above, the adhesive force can be reduced, but when the compound represented by Chemical Formula 4 above is mixed with the acrylic copolymer and the crosslinking agent, the adhesive force and the bending properties can be improved while maintaining the elasticity and the crosslinking degree by the chain extension effect.

[0118] The content of the compound represented by Chemical Formula 4 above can be 1.0 to 10 parts by weight, and preferably, 1.0 to 8.0 parts by weight, with respect to 100 parts by weight of the acrylic copolymer.

[0119] In the case where the content of the compound represented by Chemical Formula 4 above is less than 1.0 parts by weight with respect to 100 parts by weight of the acrylic copolymer, the input effect is minimal and there is no improvement effect in the adhesive force and the bending properties. In the case where it is more than 10 parts by weight with respect to 100 parts by weight of the acrylic copolymer, the cohesion in the adhesive is reduced due to excessive chain extension, and thus the adhesive cohesion can be damaged to cause a reduction in the adhesive force.

[0120] Silane coupling agent

[0121] The adhesive composition of the present application can further include one or more silane coupling agents selected from the group consisting of compounds represented by Chemical Formulas 7 and 8 below.

[0122] One or more silane coupling agents selected from the group consisting of compounds represented by Chemical Formulas 7 and 8 above can enhance the compatibility of the adhesive composition, improve the adhesive force, and can inhibit the generation of bubbles, peeling, and cracking of the adhesive layer.

[0123] The silane coupling agent described above can contain a nitrogen atom or a sulfur atom, in which case the adhesion durability and reliability can be improved even when left for a long time under heat- and moisture-resistant conditions.

[0124] [Chemical Formula 7]

[0125]

[0126] In the chemical formula 7 described above, R3is an alkyl group having 1 to 12 carbon atoms, R4are each independently a divalent aliphatic hydrocarbon group having 1 to 30 carbon atoms, and R5to R7are each independently hydrogen, an alkyl group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, an alkynyl group having 2 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms.

[0127] [Chemical Formula 8]

[0128]

[0129] In the chemical formula 8 described above, R8is an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms, R9is a divalent aliphatic hydrocarbon group having 1 to 30 carbon atoms, and R 10 12 are each independently hydrogen, an alkyl group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, an alkynyl group having 2 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms.

[0130] Specifically, the silane coupling agent described above has a trimethoxysilyl group, which is preferable in terms of achieving the purposes and effects of the present application.

[0131] The compound represented by the chemical formula 7 described above can be, for example, a compound represented by the following chemical formula 7-1, and the compound represented by the chemical formula 8 described above can be, for example, a compound represented by the following chemical formula 8-1.

[0132] [Chemical Formula 7-1]

[0133]

[0134] [Chemical Formula 8-1]

[0135]

[0136] The content of the silane coupling agent described above can be 0.01 to 3 parts by weight, and preferably, 0.1 to 2 parts by weight, with respect to 100 parts by weight of the acrylic copolymer. Within the range described above, the durability and adhesion of the adhesive layer formed from the adhesive composition can be improved.

[0137] Additive

[0138] ​In order to adjust the required adhesion, cohesion, tackiness, modulus of elasticity, glass transition temperature, etc. according to the use, the above-mentioned adhesive composition can further contain, as necessary, usual additives known in the art. For example, one or more selected from the group consisting of a crosslinking agent, an antistatic agent, a surfactant, an adhesion promoter, and a coagulation inhibitor can be contained.

[0139] The adhesive composition of the present application can further contain a crosslinking agent to enhance the cohesion of the adhesive.

[0140] The above-mentioned crosslinking agent is not particularly limited as long as it is a component capable of enhancing the cohesion of the adhesive by appropriately crosslinking the above-mentioned acrylic copolymer.

[0141] The above-mentioned crosslinking agent can be exemplified by, for example, an isocyanate-based crosslinking agent, an epoxy-based crosslinking agent, an oxazoline-based crosslinking agent, a nitridine-based crosslinking agent, a metal chelate-based compound, etc. They can be used alone or in combination of two or more.

[0142] As examples of the above-mentioned isocyanate-based crosslinking agent, there can be mentioned a polyfunctional isocyanate compound such as toluene diisocyanate, xylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, tetramethyl xylene diisocyanate, or naphthalene diisocyanate, or a compound obtained by reacting the above-mentioned polyfunctional isocyanate compound with a polyol compound such as trimethylolpropane, etc. They can be used alone or in combination of two or more.

[0143] As examples of the above-mentioned epoxy-based crosslinking agent, there can be mentioned ethylene glycol diglycidyl ether, triglycidyl ether, trimethylolpropane triglycidyl ether, N,N,N',N'-tetraglycidyl ethylenediamine, and glycerol diglycidyl ether, etc. They can be used alone or in combination of two or more.

[0144] As examples of the above-mentioned oxazoline-based crosslinking agent, there can be mentioned a copolymer obtained by polymerizing at least one monomer containing an oxazoline group such as 2-vinyl-2-oxazoline, 2-vinyl-4-methyl-2-oxazoline, 2-vinyl-5-methyl-2-oxazoline, 2-isopropenyl-2-oxazoline, 2-isopropenyl-4-methyl-2-oxazoline, 2-isopropenyl-5-ethyl-2-oxazoline, etc. They can be used alone or in combination of two or more.

[0145] As examples of the above-mentioned nitridine crosslinking agent, there can be mentioned N,N'-toluene-2,4-bis(l-nitridinocarboxamide), N,N'-diphenylmethane-4,4'-bis(l-nitridinocarboxamide), triethylene melamine, bis-isopropionyl-l-(2-methyl-nitridine), and tri-l-nitridinyl phosphine oxide, etc. They can be used alone or in combination of two or more.

[0146] As the above metal chelate crosslinking agent, a compound in which a polyvalent metal such as aluminum, iron, zinc, tin, titanium, antimony, magnesium, and / or vanadium is coordinated with acetylacetone or ethyl acetoacetate, or the like can be given. They can be used alone or in combination of two or more.

[0147] The content of the above crosslinking agent is preferably 0.1 to 1 parts by weight, more preferably 0.1 to 0.6 parts by weight, with respect to 100 parts by weight of the above acrylic copolymer. When the content of the crosslinking agent is less than 0.1 parts by weight, the adhesion or cohesion of the adhesive composition can be reduced, and when it is more than 1 part by weight, the compatibility can be reduced to cause surface migration, and the crosslinking reaction can proceed excessively to reduce the adhesion.

[0148] The adhesive composition of the present application can further include an antistatic agent, and the above antistatic agent can be an ionic antistatic agent, and as an antistatic agent including an ionic salt composed of an anion and a cation, ionic conductivity can be imparted to the adhesive layer formed from the adhesive composition.

[0149] The above ionic antistatic agent can include an alkali metal salt, an ionic liquid, or an ionic solid, and preferably can include an ionic solid.

[0150] By including an ionic solid as the ionic antistatic agent, the stability against the passage of time of the adhesive composition and the durability of the adhesive layer can be improved. In addition, the ionic solid has high compatibility with the above other components, and the transparency of the adhesive composition can be maintained high.

[0151] The cation of the above ionic solid can include imidazolium, pyridinium, alkylammonium, alkylpyrrolidinium, and / or alkylphosphonium, or the like.

[0152] In some embodiments, the content of the above ionic antistatic agent can be 0.01 to 5 parts by weight with respect to 100 parts by weight of the acrylic copolymer. Within the above range, the antistatic property of the adhesive layer can be improved, and the durability of the adhesive layer can be maintained excellent.

[0153] The adhesive composition of the present application can use a surfactant to further improve the film formation property, and preferably can use a silicone-based, fluorine-based, ester-based, cationic, anionic, nonionic, amphoteric surfactant, or the like.

[0154] The above silicone-based surfactant has, for example, as a commercial product, DC3PA, DC7PA, SH-11PA, SH-21PA, and SH-8400, or the like of Dow Corning Toray Silicone Co., Ltd., and TSF-4440, TSF-4300, TSF-4445, TSF-4446, TSF-4460, and TSF-4452, or the like of GE Toshiba Silicone Co., Ltd.

[0155] As the fluorine-based surfactants, for example, Megafac F-470, F-471, F-475, F-482, F-489, and F-554 (manufactured by Dainippon Ink and Chemicals, Incorporated) can be mentioned.

[0156] Further, as other commercially available products that can be used, KP (Shin-etsu Chemical Co., Ltd.), POLYFLOW (Kyoeisha Chemical Co., Ltd.), EFTOP (Tokyo Chemical Industry Co., Ltd.), MEGAFAC (Dainippon Ink and Chemicals, Incorporated), Flourad (Sumitomo 3M Co., Ltd.), Asahi guard, Surflon (both manufactured by Asahi Glass Co., Ltd.), SOLSPERSE (Lubrisol), EFKA (EFKA Chemicals), PB 821 (Ajinomoto Co., Inc.), and Disperbyk series (BYK-chemi) can be mentioned.

[0157] Each of the above-mentioned surfactants can be used alone or in combination of two or more, and the content thereof can be usually 0.01 to 5 parts by weight and preferably 0.05 to 2 parts by weight, relative to 100 parts by weight of the adhesive composition.

[0158] The adhesive composition of the present application can use an adhesion promoter to enhance the adhesion, and the content thereof can be usually 0.01 to 5 parts by weight and preferably 0.05 to 2 parts by weight, relative to 100 parts by weight of the adhesive composition.

[0159] The kind of the above-mentioned adhesion promoter is not particularly limited, and as specific examples of the adhesion promoter that can be used, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris(2-methoxyethoxy)silane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropyltrimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-isocyanatepropyltrimethoxysilane, and 3-isocyanatepropyltriethoxysilane can be mentioned.

[0160] The kind of the above-mentioned anti-coagulation agent is not particularly limited, but as specific examples that can be used, sodium polyacrylate and the like can be mentioned, and the content thereof can be usually 0.01 to 5 parts by weight and preferably 0.05 to 2 parts by weight, relative to 100 parts by weight of the adhesive composition.

[0161] <Adhesive sheet and display>

[0162] The present application provides an adhesive sheet manufactured from the above-described adhesive composition. In order to provide the adhesive sheet of the present application, in addition to the above-described adhesive composition, the constitution and manufacturing method generally used in order to manufacture an adhesive layer, adhesive film, and adhesive sheet in the same field can be used.

[0163] In addition, the present application provides a display including the above-described adhesive sheet. The display of the present application can include the constitution generally known in the technical field as long as it includes the adhesive composition and adhesive sheet of the present application.

[0164] The biomass degree of the adhesive sheet formed from the above-described adhesive composition of the present application, calculated according to ASTM D6866 and according to the following Formula 1, can be 30% or more.

[0165] [Formula 1]

[0166] Biomass degree (%) = Number of carbon atoms from biomass / Total number of carbon atoms x 100

[0167] The present application calculates the biomass degree according to the above-described Formula 1, and thus the biomass degree can be more accurately and easily confirmed.

[0168] In the case where the above-described biomass degree is satisfied, the carbon content ratio from biomass in the adhesive can be increased, and carbon dioxide in the atmosphere is not increased, and thus it is environmentally friendly.

[0169] In addition, the above-described adhesive sheet manufactured from the adhesive composition of the present application is excellent in durability in that it prevents the generation of bubbles or peeling even in a severe environment of a high temperature region of 50 to 100°C and / or a high humidity region of a relative humidity of 70% or more.

[0170] In the case where the adhesive sheet excellent in durability is applied to a display, since the durability and bending characteristics are not reduced, a display excellent in reliability can be provided, and it is preferred in terms of environmental cost.

[0171] Hereinafter, specific examples for implementing the present application will be described, but the present application is not limited by the following contents, and can be appropriately changed according to the degree required in the general field.

[0172] <Synthesis Example 1: Compound of Chemical Formula 3>

[0173] Bio-Butanol (Product Code W217816, Sigma-Aldrich) and acrylic acid were stirred at 80°C for 3 hours under an acid catalyst to perform synthesis. The biomass degree of the synthesized compound of Chemical Formula 3, calculated according to ASTM D6866 and according to the above-described Formula 1, was 57%.

[0174] <Manufacturing Example: Acrylic Copolymer Manufacturing>

[0175] Production example 1

[0176] In a 1L reactor under nitrogen gas reflux and provided with a cooling device so as to easily adjust the temperature, 100 parts by weight of a monomer mixture consisting of n-butyl acrylate (BA) 68.8 parts by weight, methacrylate (MA) 30 parts by weight, acrylic acid (AA) 0.2 parts by weight, 2-hydroxyethyl methacrylate (2-HEMA) 1.0 parts by weight was put in, and then 100 parts by weight of ethyl acetate (EA) was put in as a solvent. Thereafter, in order to remove oxygen, 1 hour of nitrogen gas was put in for replacement, and then the temperature was maintained at 62°C. After the above mixture was uniformly mixed, 0.07 parts by weight of azobisisobutyronitrile (AIBN) was put in as a reaction initiator and reacted for 8 hours, thereby manufacturing an acrylic copolymer having a molecular weight of about 1.24 million.

[0177] Production examples 2 to 8

[0178] The same as Manufacturing Example 1 was manufactured, but the acrylic copolymer was manufactured according to the composition of Table 1 below.

[0179] [Table 1]

[0180]

[0181] Compound of Chemical Formula 2: NOAA (Osaka Organic), biomass degree of 73% calculated according to ASTM D6866 and the above Formula 1

[0182] Compound of Chemical Formula 3: Compound synthesized in Synthesis Example 1, biomass degree of 57%

[0183] BA: Butyl acrylate (Sigma Aldrich)

[0184] MA: Methyl acrylate (Sigma Aldrich)

[0185] 2-HMEA: 2-Hydroxyethyl methacrylate (Sigma Aldrich)

[0186] AA: Acrylic acid (Sigma Aldrich)

[0187] <Example and Comparative Example: Adhesive Composition and Adhesive Sheet Manufacturing>

[0188] An adhesive composition was manufactured from the composition of Table 2 below, coated on a release film coated with a silicone release agent, dried at 100°C for 2 minutes to form an adhesive layer having a thickness of 20 μm. A triacetyl cellulose (TAC) film subjected to a corona discharge treatment was laminated on the above-formed adhesive layer, thereby manufacturing an adhesive sheet.

[0189] [Table 2]

[0190]

[0191] Compound of Formula 5: Poly-pale (Eastman Chemical)

[0192] Compound of Formula 6: Dymerex (Eastman Chemical)

[0193] Compound of Formula 7-1: HISC-06 (HANIN FINE CHEM)

[0194] Compound of Formula 8-1: HISC-03 (HANIN FINE CHEM)

[0195] Crosslinking agent: D-110N (Mitsui Chemicals)

[0196] Antistatic agent: 1-octyl-4-methylpyridinium hexafluorophosphate

[0197] [Experimental Examples]

[0198] The physical properties of the adhesive compositions and adhesive sheets manufactured in the above examples and comparative examples were measured according to the following methods, and the results are shown in Table 3 below.

[0199] (1) Biomass degree calculation

[0200] For the adhesive layer of the adhesive sheet, the carbon of biological origin and the carbon of fossil fuel origin were distinguished according to ASTM D6866, and the biomass degree was calculated according to the following Formula 1.

[0201] [Formula 1]

[0202] Biomass degree (%) = number of carbon atoms of biological origin / total number of carbon atoms x 100

[0203] (2) Adhesion evaluation

[0204] The above manufactured adhesive sheet was cut into a length of 25 mm x width of 100 mm and the release film was peeled off, and the exposed adhesive layer was attached to a glass substrate (#1737, manufactured by Corning) at a pressure of 0.25 MP, and autoclave treatment was performed at a temperature of 50°C and a pressure of 5 atm for 20 minutes, thereby manufacturing a test sheet. In order to measure the room temperature adhesion, the above manufactured test sheet was left to stand at a temperature of 23°C and a humidity of 50% RH for 24 hours. The adhesive sheet was peeled from the glass substrate at a peeling speed of 300 mm / min and a peeling angle of 180° using a universal tensile testing machine (UTM, manufactured by Instron), thereby measuring the room temperature adhesion.

[0205] To measure the heat adhesion, the test piece produced above was left for 48 hours under conditions of a temperature of 50°C and a RH of 50%. Then, the adhesive sheet was peeled from the glass substrate at a peeling speed of 300 mm / min and a peeling angle of 180° under conditions of a temperature of 23°C and a RH of 50% using a universal tensile testing machine (UTM, manufactured by Instron), whereby the heat adhesion was measured.

[0206] (3) Evaluation of Bending Properties

[0207] After the adhesive composition produced above was coated on a release film coated with a silicone release agent and dried, it was laminated to one side of a polarizing plate in which a Triacetylcellulose (TAC) film was attached to the upper and lower portions of a dyed and stretched PVA polarizer using an adhesive, and then cut into a length of 200 mm x a width of 120 mm and the release film was peeled off, and the exposed adhesive layer was attached to a glass substrate (210 mm x 130 mm x 0.5 mm), whereby a test piece was produced.

[0208] In the heat resistance evaluation and the humidity resistance evaluation, after each was left for 500 hours under conditions of 80°C and 60°C, 90% RH, respectively, it was taken out of the oven, and the height of warpage at the four corners was measured and the average was calculated. At this time, it was taken out of the oven before the height of the test piece was measured, left for 30 minutes, and then placed on a stage to be measured.

[0209] (4) Evaluation of Reliability

[0210] After the produced adhesive sheet was cut into a length of 200 mm x a width of 300 mm and the release film was peeled off, the exposed adhesive layer was attached to a glass substrate (210 mm x 350 mm x 0.7 mm) and autoclave-treated (50°C x 30 minutes, 0.5 MPa), whereby a test piece was produced. At this time, the pressure applied was 5 kg / cm 2 , and clean room operation was performed to prevent the generation of bubbles or foreign matter. In the heat resistance evaluation and the humidity resistance evaluation, after each was left for 500 hours under conditions of 80°C and 60°C, 90% RH, respectively, it was taken out of the oven, and whether bubbles or peeling occurred was observed. At this time, the state of the test piece was that it was taken out of the oven and left for 24 hours at ordinary temperature before observation.

[0211] <Evaluation Criteria>

[0212] ◎: No bubbles or peeling;

[0213] O: Bubbles or peeling were less than 5;

[0214] Δ: Bubbles or peeling were 5 or more but less than 10;

[0215] X: Bubbles or peeling were 10 or more.

[0216] [Table 3]

[0217]

[0218]

[0219] It can be confirmed from the above Table 3 that the adhesive sheet manufactured using the adhesive composition of the embodiment of the present application has an excellent biomass degree of 30% or more, the heat resistance at high temperature does not decrease while maintaining the adhesive force, and the reliability is maintained, and the bending property is improved by further including the compound represented by Chemical Formula 4.

[0220] In addition, it can be confirmed that in the case where the compound represented by Chemical Formula 2 and the compound represented by Chemical Formula 3 are included as the compound represented by Chemical Formula 1 of the present application, the bending property is further improved compared to the case where only either of them is included.

[0221] On the other hand, it can be confirmed that the adhesive force of Example 3 including the compound represented by Chemical Formula 1 of the present application but increasing the content of the crosslinking agent decreases, and the adhesive force of Examples 4, 14, and 15 including the compound of Chemical Formula 4 but having the same content of the crosslinking agent as Example 3 increases.

[0222] On the contrary, it can be confirmed that in the case of Comparative Example 1 not including the compound represented by Chemical Formula 1 of the present application, the biomass degree is 0, and the result of the deterioration of the bending property at high temperature and high humidity is shown.

Claims

1. An adhesive composition comprising an acrylic copolymer polymerized from a compound represented by the following chemical formula 1: Chemical Formula 1 In the chemical formula 1, R1 is hydrogen or methyl. R2 is a hydrocarbon group derived from biomass with 1 to 9 carbon atoms.

2. The adhesive composition according to claim 1, wherein the compound represented by chemical formula 1 comprises one or more compounds selected from the group consisting of compounds represented by chemical formulas 2 and 3: Chemical formula 2 Chemical formula 3 3. The adhesive composition according to claim 1, wherein the compound represented by chemical formula 1 comprises the compound represented by chemical formula 2 and the compound represented by chemical formula 3: Chemical formula 2 Chemical formula 3 4. The adhesive composition according to claim 3, wherein the compound represented by chemical formula 2 and the compound represented by chemical formula 3 are contained in a ratio of 1:10 to 10:

1.

5. The adhesive composition according to claim 1, wherein the content of the compound represented by formula 1 is 30 to 80% by weight relative to the total weight of monomers used in the polymerization of the acrylic copolymer.

6. The adhesive composition according to any one of claims 1 to 5, further comprising a compound represented by chemical formula 4. Chemical Formula 4 In the chemical formula 4, Ra to Rc are each independently a substituted or unsubstituted alkyl group with 1 to 30 carbon atoms, a substituted or unsubstituted cycloalkyl group with 3 to 30 carbon atoms, a substituted or unsubstituted heterocycloalkyl group with 3 to 30 carbon atoms, a substituted or unsubstituted aryl group with 6 to 30 carbon atoms, a substituted or unsubstituted arylene group with 6 to 30 carbon atoms, or a substituted or unsubstituted heteroarylene group with 6 to 30 carbon atoms. Any two of Ra to Rc can be combined to form a ring system.

7. The adhesive composition according to claim 6, wherein the compound represented by chemical formula 4 comprises one or more compounds selected from the group consisting of compounds represented by chemical formulas 5 and 6: Chemical formula 5 Chemical Formula 6 8. The adhesive composition according to claim 6, wherein the content of the compound represented by chemical formula 4 is 1.0 to 10 parts by weight relative to 100 parts by weight of the acrylic copolymer.

9. The adhesive composition according to any one of claims 1 to 5, further comprising one or more silane coupling agents selected from the group consisting of compounds represented by the following chemical formulas 7 and 8: Chemical Formula 7 In the chemical formula 7 R3 is an alkyl group having 1 to 12 carbon atoms. R4 is an independent divalent aliphatic hydrocarbon group with 1 to 30 carbon atoms. R5 to R7 are each independently hydrogen, an alkyl group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, an alkynyl group having 2 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. Chemical Formula 8 In the chemical formula 8, R8 is an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms. R9 is a divalent aliphatic hydrocarbon group with 1 to 30 carbon atoms. R 10 ~R 12 Each of them is independently hydrogen, an alkyl group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, an alkynyl group having 2 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms.

10. The adhesive composition according to claim 9, wherein the content of the silane coupling agent is 0.01 to 3 parts by weight relative to 100 parts by weight of the acrylic copolymer.

11. The adhesive composition according to any one of claims 1 to 5, wherein the biomass content of the adhesive sheet formed from said adhesive composition, calculated according to ASTM D6866 and Formula 1 below, is 30% or more. Formula 1 Biomass quality = (Number of carbon atoms in the biomass source / Total number of carbon atoms) × 100 in, The unit for biomass quality is %.

12. The adhesive composition according to any one of claims 1 to 5, wherein the adhesive composition further comprises one or more of the group selected from the group consisting of crosslinking agents, antistatic agents, surfactants, adhesion promoters and anti-caking agents.

13. An adhesive sheet comprising the adhesive composition according to any one of claims 1 to 12.

14. A display comprising the adhesive sheet of claim 13.

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