KR20220132208A - Resin composition and optically clear adhesive - Google Patents

Abstract

This application relates to a pressure-sensitive adhesive composition and an optical pressure-sensitive adhesive. Through a combination of monomers having a specific glass transition temperature and surface tension at room temperature, and the content ratios thereof, the present invention makes it possible to provide a pressure-sensitive adhesive composition that has excellent wettability and light resistance, and is capable of covering steps and defects, and an optical adhesive capable of covering defects located between laminated layers of a display device or a transparent electrode.

Description

Adhesive composition and optical adhesive {Resin composition and optically clear adhesive}

The present application relates to a pressure-sensitive adhesive composition and an optical pressure-sensitive adhesive formed by the pressure-sensitive adhesive composition.

Optically Clear Adhesive (OCA) is an adhesive inserted to bond between functional layers constituting a display product or a product including a transparent electrode (hereinafter, a transparent electrode product), and the adhesive strength of the optical adhesive to perform a function is important In particular, there are cases where the functional layer is provided with two or more different materials or parts, and even in this case, both of them are required to have excellent adhesion. In Patent Document 1, an optical pressure-sensitive adhesive that uses a partially polymerized acrylic resin to secure excellent adhesion to a glass substrate is known.

In display products or transparent electrode products containing an optical adhesive, bubbles or floating between the laminated layers occur due to various reasons such as foreign substances included in the glass substrate or penetrating between processes, gas generated from the optical adhesive or polarizing plate, and thermal contraction of the polarizing plate. became In particular, the bubble generation or the lifting phenomenon between the laminated layers was mainly caused by a defect located between the laminated layers of a display product or a transparent electrode product acting as a nucleus.

Conventional optical adhesives formed to have a high crosslinking density and a glass transition temperature by introducing an excess of a crosslinking agent and a monomer with high thermal stability showed excellent stability in high temperature, high temperature/high humidity and thermal shock evaluation, but bubble generation or floatation between the laminated layers The phenomenon occurred conspicuously.

Therefore, an optical pressure-sensitive adhesive capable of preventing the occurrence of bubbles or lifting between the laminated layers while having stability was required.

Republic of Korea Patent Publication No. 10-2016-0105354

An object of the present application is to provide a pressure-sensitive adhesive composition and an optical pressure-sensitive adhesive that can solve the above problems.

In addition, an object of the present application is to provide an adhesive composition that has excellent wettability and light resistance, and forms an optical adhesive capable of covering a step and a foreign substance (defect).

In addition, an object of the present application is to provide a pressure-sensitive adhesive composition for forming an optical pressure-sensitive adhesive capable of minimizing the occurrence of bubbles or the lifting phenomenon between the lamination layers while satisfying basic required physical properties such as durability and adhesive strength.

In addition, an object of the present application is to provide an optical pressure-sensitive adhesive capable of covering a foreign material (defect) located between the laminated layer of a display product or a transparent electrode product.

Room temperature, the term used in this application, is a temperature in a natural state that is not specially heated or reduced, and any one temperature within the range of about 10 ° C to 30 ° C, for example, about 15 ° C. or more, about 18 ° C. or more, about 20 ℃ or higher, or about 23 ℃ or higher, may mean a temperature of about 27 ℃ or less.

Surface tension, a term used in this application, is a force acting in a direction to minimize the surface of a liquid material, and is measured according to ISO 304 using a surface tension meter using a platinum ring. can be a value. In addition, the room temperature surface tension, which is a term used in the present application, may be a value measured according to the above method in a room temperature environment. In addition, the room temperature may be specifically about 25 ℃ here.

Substitution, a term used in the present application, means that a hydrogen atom bonded to a carbon atom of a compound is changed to another substituent, and the position to be substituted is not particularly limited as long as the position at which the hydrogen atom is substituted, that is, the position where the substituent is substitutable, is not particularly limited. In the case of more than one substitution, the substituents may be the same or different from each other.

As used herein, the term "substituent" refers to an atom or group of atoms that replaces one or more hydrogen atoms on the parent chain of a hydrocarbon. In this case, the carbon in the parent chain of the hydrocarbon bonded to the substituent is defined as a substituted carbon in the present application. In addition, the substituents are described below, but are not limited thereto, and the substituents may be further substituted with the substituents described below or not substituted with any substituents unless otherwise specified in the present application.

Unless otherwise stated, the term alkyl group or alkylene group used in the present application has 1 to 20 carbon atoms, or 1 to 16 carbon atoms, or 1 to 12 carbon atoms, or 1 to 8 carbon atoms, or a straight chain or branched chain having 1 to 6 carbon atoms. It may be a chain alkyl group or an alkylene group, or a cyclic alkyl group or alkylene group having 3 to 20 carbon atoms, or 3 to 16 carbon atoms, or 3 to 12 carbon atoms, or 3 to 8 carbon atoms, or 3 to 6 carbon atoms. Here, the cyclic alkyl group or alkylene group includes an alkyl group or alkylene group having only a ring structure, and an alkyl group or alkylene group including a ring structure. For example, both a cyclohexyl group and a methyl cyclohexyl group correspond to a cyclic alkyl group.

The term alkenyl group or alkenylene group used in the present application, unless otherwise specified, has 2 to 20 carbon atoms, or 2 to 16 carbon atoms, or 2 to 12 carbon atoms, or 2 to 8 carbon atoms, or 2 to 6 carbon atoms straight chain or branched. an acyclic alkenyl group or an alkenylene group in the chain; It may be a cyclic alkenyl group or alkenylene group having 3 to 20 carbon atoms, or 3 to 16 carbon atoms, or 3 to 12 carbon atoms, or 3 to 8 carbon atoms, or 3 to 6 carbon atoms. Here, when an alkenyl group or an alkenylene group of a ring structure is included, it corresponds to a cyclic alkenyl group or an alkenylene group.

An alkynyl group or alkynylene group as used in the present application, unless otherwise specified, has 2 to 20 carbon atoms, or 2 to 16 carbon atoms, or 2 to 12 carbon atoms, or 2 to 8 carbon atoms, or 2 to 6 carbon atoms straight chain or branched. A chain alkynyl or alkynylene group, or a cyclic alkynyl group or alkynylene having 3 to 20 carbon atoms, or 3 to 16 carbon atoms, or 3 to 12 carbon atoms, or 3 to 8 carbon atoms, or 3 to 6 carbon atoms it can be a gimmick Here, when an alkynyl group or an alkynylene group of a ring structure is included, it corresponds to a cyclic alkynyl group or an alkynylene group.

The alkyl group, alkylene group, alkenyl group, alkenylene group, and alkynyl group may be optionally substituted with one or more substituents. In this case, the substituent includes halogen (chlorine (Cl), iodine (I), bromine (Br), fluorine (F)), an aryl group, a heteroaryl group, an ether group, a carbonyl group, a carboxyl group and a hydroxyl group. It may be one or more selected from, but is not limited thereto.

The aryl group as a term used in the present application means an aromatic ring in which one hydrogen is removed from an aromatic hydrocarbon ring, and the aromatic hydrocarbon ring may include a monocyclic or polycyclic ring. The aryl group has 6 to 30 carbon atoms, or 6 to 26 carbon atoms, or 6 to 22 carbon atoms, or 6 to 20 carbon atoms, or 6 to 18 carbon atoms, or an aryl group having 6 to 18 carbon atoms, or 2 to 15 carbon atoms unless otherwise specified. may be In addition, the term arylene group used in the present application means that the aryl group has two bonding positions, that is, a divalent group. Except that each of these is a divalent group, the description of the aryl group described above may be applied.

The term heteroaryl group used in the present application is an aromatic ring containing one or more heteroatoms other than carbon, and specifically, the heteroatoms are nitrogen (N), oxygen (O), sulfur (S), selenium (Se) and tele It may include one or more atoms selected from the group consisting of nium (Te). In this case, the atoms constituting the ring structure of the heteroaryl group may be referred to as reducing atoms. In addition, the heteroaryl group may include a monocyclic or polycyclic ring. The heteroaryl group has 2 to 30 carbon atoms, or 2 to 26 carbon atoms, or 2 to 22 carbon atoms, or 2 to 22 carbon atoms, or 2 to 20 carbon atoms, or 2 to 18 carbon atoms, or 2 to 15 carbon atoms unless otherwise specified. It may be a heteroaryl group. In another example, the heteroaryl group does not specifically limit the number of reducing atoms, but may be a heteroaryl group having 5 to 30, 5 to 25, 5 to 20, 5 to 15, 5 to 10, or 5 to 8 reducing atoms.

In addition, the term heteroarylene group used in the present application means that the heteroaryl group has two bonding positions, that is, a divalent group. Except that each of these is a divalent group, the description of the heteroaryl group described above may be applied.

The term acrylate compound used in the present application means acrylic acid, methacrylic acid, a derivative of acrylic acid, or a derivative of methacrylic acid. In addition, the term (meth)acryl used in the present application means acryl or methacryl.

In an example of the present application, the pressure-sensitive adhesive composition includes a copolymer obtained by copolymerizing two or more monomers, and the monomer includes a monomer having a surface tension of more than 30 mN/m at room temperature and a monomer having a surface tension of 30 mN/m or less at room temperature. can do.

In addition, in an example of the present application, the copolymer of the pressure-sensitive adhesive composition may have a room temperature surface tension of 30 mN/m or less, 29.5 mN/m or less, 29 mN/m or less, 28.5 mN/m or less, or 28 mN/m or less, In another example, the copolymer of the pressure-sensitive adhesive composition may have a surface tension of 20 mN/m or more, 21 mN/m or more, 22 mN/m or more, or 23 mN/m or more at room temperature.

The room temperature surface tension of the pressure-sensitive adhesive composition may be affected by the room temperature surface tension of the copolymer included therein. In an example of the present application, the room temperature surface tension of the pressure-sensitive adhesive composition may be 30 mN/m or less, 29.5 mN/m or less, 29 mN/m or less, 28.5 mN/m or less, or 28 mN/m or less, and in another example, the The surface tension of the pressure-sensitive adhesive composition may be at least 20 mN/m, at least 21 mN/m, at least 22 mN/m, or at least 23 mN/m. When the room temperature surface tension of the pressure-sensitive adhesive composition satisfies the above range, the room temperature surface tension of the copolymer included in the pressure-sensitive adhesive composition may also satisfy the above range.

In an example of the present application, the monomer included in the pressure-sensitive adhesive composition may satisfy the following general formula (1).

[General formula 1]

3 ≤ A/B×100 ≤ 30

In General Formula 1, A represents the weight of a monomer having a surface tension of more than 30 mN/m at room temperature, and B represents the weight of a monomer having a surface tension of 30 mN/m or less at room temperature.

In addition, the value of A/B×100 in Formula 1 may be 3 or more, 3.5 or more, 4 or more, 4.5 or more, 5 or more, 5.5 or more, or 6 or more, and in another example, A/B×100 in General Formula 1 The value of may be 30 or less, 28 or less, 26 or less, 24 or less, or 22 or less. In addition, the value of A/B×100 in Formula 1 may be within a range formed by appropriately selecting the upper and lower limits listed above.

When the value of A/B×100 in Formula 1 satisfies the above range, it is possible to form an adhesive composition having excellent wettability and light resistance to cover steps and defects.

In an example of the present application, the monomer included in the pressure-sensitive adhesive composition may additionally include a monomer having a glass transition temperature of more than 10°C and a monomer having a glass transition temperature of 10°C or less.

In an example of the present application, the copolymer of the pressure-sensitive adhesive composition has a glass transition temperature of -25 ℃ or less, -26 ℃ or less, -27 ℃ or less, -28 ℃ or less, -29 ℃ or less, -30 ℃ or less, -31 ℃ Below, it may be -32 ℃ or less, -33 ℃ or less, or -34 ℃ or less, and in another example, the copolymer of the pressure-sensitive adhesive composition has a glass transition temperature of -50 ℃ or more, -49.5 ℃ or more, -49 ℃ or more, or -48.5 ℃ or higher.

The glass transition temperature of the pressure-sensitive adhesive composition may be affected by the glass transition temperature of the copolymer included. In an example of the present application, the glass transition temperature of the pressure-sensitive adhesive composition is -25 ℃ or less, -26 ℃ or less, -27 ℃ or less, -28 ℃ or less, -29 ℃ or less, -30 ℃ or less, -31 ℃ or less, - It may be 32 ℃ or less, -33 ℃ or less, or -34 ℃ or less, and in another example, the glass transition temperature of the pressure-sensitive adhesive composition may be -50 ℃ or more, -49.5 ℃ or more, -49 ℃ or more, or -48.5 ℃ or more. When the glass transition temperature of the pressure-sensitive adhesive composition satisfies the above range, the glass transition temperature of the copolymer included in the pressure-sensitive adhesive composition may also satisfy the above range.

In an example of the present application, the monomer included in the pressure-sensitive adhesive composition may satisfy the following general formula (2).

[General formula 2]

1 ≤ C/D×100 ≤ 22

In General Formula 2, C represents the weight of a monomer having a glass transition temperature of more than 10° C., and D represents the weight of a monomer having a glass transition temperature of 10° C. or less.

In addition, in General Formula 2, the value of C/D×100 may be 1 or more, 1.5 or more, 2 or more, 2.5 or more, 3 or more, 3.5 or more, 4 or more, 4.5 or more, 5 or more, 5.5 or more, or 6 or more, and other In an example, the value of C/D×100 in Formula 2 may be 22 or less, 21 or less, 20 or less, 19 or less, or 18 or less. In addition, the value of C/D×100 in Formula 2 may be within a range formed by appropriately selecting the upper and lower limits listed above.

When the value of C/D×100 in General Formula 2 satisfies the above range, a pressure-sensitive adhesive composition having an appropriate storage elastic modulus and tensile modulus may be formed.

In another example of the present application, the pressure-sensitive adhesive composition includes a copolymer obtained by copolymerizing two or more monomers, the room temperature surface tension of the copolymer is 30 mN/m or less, and the glass transition temperature may be -25 ℃ or less. .

In another example of the present application, the copolymer of the pressure-sensitive adhesive composition may have a room temperature surface tension of 30 mN/m or less, 29.5 mN/m or less, 29 mN/m or less, 28.5 mN/m or less, or 28 mN/m or less, In another example, the copolymer of the pressure-sensitive adhesive composition may have a surface tension of 20 mN/m or more, 21 mN/m or more, 22 mN/m or more, or 23 mN/m or more at room temperature.

The room temperature surface tension of the pressure-sensitive adhesive composition may be affected by the room temperature surface tension of the copolymer included therein. In an example of the present application, the room temperature surface tension of the pressure-sensitive adhesive composition may be 30 mN/m or less, 29.5 mN/m or less, 29 mN/m or less, 28.5 mN/m or less, or 28 mN/m or less, and in another example, the The surface tension of the pressure-sensitive adhesive composition may be at least 20 mN/m, at least 21 mN/m, at least 22 mN/m, or at least 23 mN/m. When the room temperature surface tension of the pressure-sensitive adhesive composition satisfies the above range, the room temperature surface tension of the copolymer included in the pressure-sensitive adhesive composition may also satisfy the above range.

In addition, the copolymer of the pressure-sensitive adhesive composition has a glass transition temperature of -25 ℃ or less, -26 ℃ or less, -27 ℃ or less, -28 ℃ or less, -29 ℃ or less, -30 ℃ or less, -31 ℃ or less, -32 ℃ Hereinafter, it may be -33 ℃ or less or -34 ℃ or less, and in another example, the copolymer of the pressure-sensitive adhesive composition has a glass transition temperature of -50 ℃ or more, -49.5 ℃ or more, -49 ℃ or more, or -48.5 ℃ or more.

The glass transition temperature of the pressure-sensitive adhesive composition may be affected by the glass transition temperature of the copolymer included. In an example of the present application, the glass transition temperature of the pressure-sensitive adhesive composition is -25 ℃ or less, -26 ℃ or less, -27 ℃ or less, -28 ℃ or less, -29 ℃ or less, -30 ℃ or less, -31 ℃ or less, - It may be 32 ℃ or less, -33 ℃ or less, or -34 ℃ or less, and in another example, the glass transition temperature of the pressure-sensitive adhesive composition may be -50 ℃ or more, -49.5 ℃ or more, -49 ℃ or more, or -48.5 ℃ or more. When the glass transition temperature of the pressure-sensitive adhesive composition satisfies the above range, the glass transition temperature of the copolymer included in the pressure-sensitive adhesive composition may also satisfy the above range.

In another example of the present application, the monomer included in the pressure-sensitive adhesive composition is a first monomer including a monomer having a surface tension of more than 30 mN/m at room temperature and a monomer having a surface tension of 30 mN/m or less at room temperature; Alternatively, it may include at least one of a second monomer including a monomer having a glass transition temperature of more than 10°C and a monomer having a glass transition temperature of 10°C or less.

The first monomer may satisfy the following general formula (1).

[General formula 1]

3 ≤ A/B×100 ≤ 30

In General Formula 1, A represents the weight of a monomer having a surface tension of more than 30 mN/m at room temperature, and B represents the weight of a monomer having a surface tension of 30 mN/m or less at room temperature.

In addition, the value of A/B×100 in Formula 1 may be 3 or more, 3.5 or more, 4 or more, 4.5 or more, 5 or more, 5.5 or more, or 6 or more, and in another example, A/B×100 in Formula 1 above The value of may be 30 or less, 28 or less, 26 or less, 24 or less, or 22 or less. In addition, the value of A/B×100 in Formula 1 may be within a range formed by appropriately selecting the upper and lower limits listed above.

When the value of A/B×100 in Formula 1 satisfies the above range, it is possible to form an adhesive composition having excellent wettability and light resistance to cover steps and defects.

The second monomer may satisfy the following general formula (2).

[General formula 2]

1 ≤ C/D×100 ≤ 22

In General Formula 2, C represents the weight of a monomer having a glass transition temperature of more than 10° C., and D represents the weight of a monomer having a glass transition temperature of 10° C. or less.

In addition, in General Formula 2, the value of C/D×100 may be 1 or more, 1.5 or more, 2 or more, 2.5 or more, 3 or more, 3.5 or more, 4 or more, 4.5 or more, 5 or more, 5.5 or more, or 6 or more, and other In an example, the value of C/D×100 may be 22 or less, 21 or less, 20 or less, 19 or less, or 18 or less. In addition, the value of C/D×100 in Formula 2 may be within a range formed by appropriately selecting the upper and lower limits listed above.

When the value of C/D×100 in General Formula 2 satisfies the above range, a pressure-sensitive adhesive composition having an appropriate storage elastic modulus and tensile modulus may be formed.

In another example of the present application, the monomer included in the pressure-sensitive adhesive composition has a glass transition temperature corresponding to a monomer having a room temperature surface tension of more than 30 mN/m of the first monomer or a monomer having a glass transition temperature of more than 10° C. of the second monomer. may include a monomer having a surface tension of more than 30 mN/m at room temperature while exceeding 10 °C.

The monomer having a glass transition temperature of more than 10 °C and a surface tension of more than 30 mN/m at room temperature is 0.5 wt% or more, 0.75 wt% or more, 1 wt% or more, 1.25 wt% or more, 1.5 wt% or more, or It may be included in 1.75 wt% or more, and in another example, the monomer having a glass transition temperature of more than 10 °C and a surface tension of more than 30 mN/m at room temperature is 18 wt% or less, 17 wt% or less, 16 wt% based on the total weight of the monomer or less or 15% by weight or less. In addition, the monomer having a glass transition temperature of more than 10° C. and a surface tension of more than 30 mN/m at room temperature may be included within the range formed by appropriately selecting the upper and lower limits listed above.

In addition, in another example of the present application, the monomer included in the pressure-sensitive adhesive composition has a glass transition temperature corresponding to a monomer having a surface tension of 30 mN/m or less at room temperature of the first monomer or a monomer having a glass transition temperature of 10° C. or less of the second monomer. may further include a monomer having a surface tension of 30 mN/m or less at room temperature while being 10° C. or less.

The glass transition temperature of the monomer having a glass transition temperature of 10 ° C or less and a room temperature surface tension of 30 mN/m or less is 450 parts by weight or more, 475 parts by weight compared to 100 parts by weight of a monomer having a glass transition temperature of more than 10 ° C and a room temperature surface tension of 30 mN/m or less. It may be included in parts or more, 500 parts by weight or more, 525 parts by weight or more, 550 parts by weight or more, or 575 parts by weight or more, and in another example, the glass transition temperature is 10 ° C. or less and the room temperature surface tension is 30 mN / m or less. 6,000 parts by weight or less, 5,800 parts by weight or less, 5,600 parts by weight or less, 5,400 parts by weight or less, 5,200 parts by weight or less, 5,000 parts by weight compared to 100 parts by weight of a monomer having a glass transition temperature of more than 10° C. and a surface tension of more than 30 mN/m It may be included in parts by weight or less or 4,800 parts by weight or less. In addition, the monomer having a glass transition temperature of 10° C. or less and a room temperature surface tension of 30 mN/m or less may be included within the range formed by appropriately selecting the upper and lower limits listed above.

A monomer having a glass transition temperature of more than 10 ° C and a room temperature surface tension of more than 30 mN/m and/or a monomer having a glass transition temperature of 10 ° C or less and a room temperature surface tension of 30 mN/m or less contained in the pressure-sensitive adhesive composition is within the above content range When satisfactory, excellent wettability and light resistance can be ensured.

In an example of the present application, the meaning that the pressure-sensitive adhesive composition may include a specific compound group means that it may include one or more compounds satisfying the specific compound group. For example, the meaning that the pressure-sensitive adhesive composition includes a chain-type alkyl acrylate compound including a compound represented by the following formula (1) means that the pressure-sensitive adhesive composition is at least one compound satisfying the structure of the compound represented by the following formula (1) This means that you can include

In an example of the present application, the monomer having a surface tension of 30 mN/m or less at room temperature of the pressure-sensitive adhesive composition may include a chain-type alkyl acrylate compound.

The term chain-type alkyl acrylate compound used in the present application may mean an acrylate compound containing a chain-type alkyl group. Here, the chain-type alkyl group may mean a straight-chain alkyl group or a branched-chain alkyl group.

The chain alkyl group may be a linear or branched alkyl group having 1 to 30 carbon atoms, or 1 to 25 carbon atoms, or 1 to 20 carbon atoms, or 1 to 15 carbon atoms, or 1 to 10 carbon atoms.

The chain-type alkyl acrylate compound may have a surface tension of 30 mN/m or less, 29 mN/m or less, 28 mN/m or less, 27 mN/m or less, 26 mN/m or less, or 25 mN/m or less at room temperature.

In addition, the chain-type alkyl acrylate compound may have a glass transition temperature of -20 °C or less, -30 °C or less, -40 °C or less, or -50 °C or less.

The chain-type alkyl acrylate compound may include at least one compound represented by the following Chemical Formula 1.

[Formula 1]

In Formula 1, L ₁ is a linear alkylene group having 1 to 14 carbon atoms or a branched chain alkylene group having 2 to 14 carbon atoms, and R ₁ and R ₂ are each independently hydrogen, a linear alkyl group having 1 to 6 carbon atoms. Or it may be a branched alkyl group having 2 to 6 carbon atoms.

In addition, in another example, L ₁ is a linear alkylene group having 1 or more, 2 or more, 3 or more, 4 or more, 5 or more, 6 or more, or 7 or more carbon atoms, or 2 or more, 3 or more, 4 or more, 5 or more, 6 or more carbon atoms. Or it may be a branched chain alkylene group of 7 or more. In another example, L ₁ may be a linear or branched alkylene group having 14 or less, 13 or less, 12 or less, 11 or less, 10 or less, 9 or less, or 8 or less carbon atoms. L ₁ may be a straight-chain or branched alkylene group having a carbon number within the range formed by appropriately selecting the upper and lower limits of the carbon number listed above.

In another example, R ₁ and R ₂ may each independently be hydrogen, a linear alkyl group having 1 to 4 carbon atoms, or a branched chain alkyl group having 2 to 4 carbon atoms, and in another example, R ₁ and R ₂ are each Independently, it may be hydrogen or a linear alkyl group having 1 to 2 carbon atoms.

The compound represented by Formula 1 may have a room temperature surface tension of 30 mN/m or less, 29 mN/m or less, 28 mN/m or less, 27 mN/m or less, 26 mN/m or less, or 25 mN/m or less.

In addition, the compound represented by Formula 1 may have a glass transition temperature of -20 °C or less, -30 °C or less, -40 °C or less, or -50 °C or less.

The compound represented by Formula 1 may be exemplified by isobutyl acrylate, isodecyl acrylate, isooctyl acrylate, ethyl acrylate, butyl acrylate and 2-ethylhexyl acrylate, and when the above-described physical properties are satisfied, This is not particularly limited.

In an example of the present application, the chain alkyl acrylate compound is 55 wt% or more, 57.5 wt% or more, 60 wt% or more, 62.5 wt% or more, or 65 wt% based on the total weight of the monomer having a surface tension of 30 mN/m or less at room temperature. It may be included in more than one, and in another example, the chain alkyl acrylate compound is included in 98 wt% or less, 97 wt% or less, 96 wt% or less, or 95 wt% or less based on the total weight of the monomer having a surface tension of 30 mN/m or less at room temperature. can In addition, the chain alkyl acrylate compound may be included within the range formed by appropriately selecting the upper and lower limits listed above.

In another example of the present application, the chain alkyl acrylate compound is 55 wt% or more, 57.5 wt% or more, 60 wt% or more, 62.5 wt% or more, or 65 wt% or more, based on the total weight of the monomer having a surface tension of 30 mN/m or less at room temperature. It may be included in an amount of not less than 70% by weight, and in another example, the chain alkyl acrylate compound may be included in an amount of 70% by weight or less, 69% by weight or less, or 68% by weight or less based on the total weight of the monomer having a room temperature surface tension of 30 mN/m or less. In addition, the chain alkyl acrylate compound may be included within the range formed by appropriately selecting the upper and lower limits listed above.

In an example of the present application, the monomer having a surface tension of 30 mN/m or less at room temperature of the pressure-sensitive adhesive composition may include a hydroxyl group-containing acrylate compound.

The hydroxyl group-containing acrylate compound may have a surface tension of 30 mN/m or less, 29 mN/m or less, or 28 mN/m or less at room temperature.

In addition, the chain-type alkyl acrylate compound may have a glass transition temperature of 0 °C or less, -5 °C or less, -10 °C or less, or -15 °C or less.

The hydroxyl group-containing acrylate compound is sufficient as long as it has a hydroxyl group and satisfies the above physical properties, and the type thereof is not particularly limited.

The hydroxyl group-containing acrylate compound may include at least one compound represented by the following formula (2).

[Formula 2]

In Formula 2, L ₂ is a linear alkylene group having 1 to 10 carbon atoms, a branched chain alkylene group having 2 to 10 carbon atoms, a linear or branched alkenylene group having 2 to 10 carbon atoms, or a straight chain alkylene group having 2 to 10 carbon atoms. It may be a chain or branched alkynylene group.

In addition, in one example, L ₂ may be a linear alkylene group having 1 or more, 2 or more, 3 or more, or 4 or more carbon atoms, and in another example, L ₂ is 10 or less, 9 or less, 8 or less, 7 or less, 6 or less carbon number. Or it may be a straight-chain alkylene group of 5 or less. L ₂ may be a straight-chain alkylene group having a carbon number within the range formed by appropriately selecting the upper and lower limits of the carbon number listed above.

In addition, in another example, L ₂ may be a branched alkylene group having 2 or more, 3 or more, or 4 or more carbon atoms, a linear or branched alkenylene group, or a straight or branched alkynylene group, and in another example, L ₂ may be a branched-chain alkylene group having 10 or less, 9 or less, 8 or less, 7 or less, 6 or less, or 5 or less carbon atoms, a straight-chain or branched alkenylene group, or a straight-chain or branched alkynylene group. L ₂ may be a branched-chain alkylene group, a straight-chain or branched alkenylene group, or a straight-chain or branched alkynylene group having a carbon number within the range formed by appropriately selecting the upper and lower limits of the carbon number listed above.

The compound represented by Formula 2 may have a surface tension of 30 mN/m or less, 29 mN/m or less, or 28 mN/m or less at room temperature.

In addition, the compound represented by Formula 2 may have a glass transition temperature of 0 °C or less, -5 °C or less, -10 °C or less, or -15 °C or less.

The compound represented by Formula 2 may be exemplified by 2-hydroxyethyl acrylate, 4-hydroxybutyl acrylate, 2-hydroxypropyl acrylate and 2-hydroxy-1-methylethyl acrylate, As long as the above-described physical properties are satisfied, the present invention is not particularly limited thereto.

In an example of the present application, the hydroxyl group-containing acrylate compound is 1 wt% or more, 2 wt% or more, 3 wt% or more, 4 wt% or more, or 5 wt% or more, based on the total weight of the monomer having a surface tension of 30 mN/m or less at room temperature. In another example, the hydroxyl group-containing acrylate compound may be included in an amount of 40 wt% or less, 38.5 wt% or less, 37 wt% or less, or 35.5 wt% or less, based on the total weight of the monomer having a surface tension of 30 mN/m or less at room temperature. . In addition, the hydroxyl group-containing acrylate compound may be included within the range formed by appropriately selecting the upper and lower limits listed above.

In another example of the present application, the hydroxyl group-containing acrylate compound may be included in an amount of 30 wt% or more, 30.5 wt% or more, 31 wt% or more, or 31.5 wt% or more, based on the total weight of the monomer having a surface tension of 30 mN/m or less at room temperature. In another example, the hydroxyl group-containing acrylate compound may be included in an amount of 40 wt% or less, 38.5 wt% or less, 37 wt% or less, or 35.5 wt% or less, based on the total weight of the monomer having a surface tension of 30 mN/m or less at room temperature. In addition, the hydroxyl group-containing acrylate compound may be included within the range formed by appropriately selecting the upper and lower limits listed above.

In an example of the present application, the monomer having a surface tension of 30 mN/m or less at room temperature of the pressure-sensitive adhesive composition may include a chain-type alkyl acrylate compound and a hydroxyl group-containing acrylate compound.

In this case, the weight ratio (P/R) of the chain alkyl acrylate compound (P) and the hydroxyl group-containing acrylate compound (R) may be 1 or more, 1.2 or more, 1.4 or more, 1.6 or more, or 1.8 or more, and 20 or less , 19.5 or less, 19 or less, or 18.5 or less. In addition, the weight ratio (P/R) of the chain alkyl acrylate compound (P) and the hydroxyl group-containing acrylate compound (R) may be included within a range formed by appropriately selecting the upper and lower limits listed above.

Further, in another example, the weight ratio (P/R) of the chain-type alkyl acrylate compound (P) and the hydroxyl group-containing acrylate compound (R) may be 1 or more, 1.2 or more, 1.4 or more, 1.6 or more, or 1.8 or more, 3.6 or less, 3.2 or less, 2.8 or less, or 2.4 or less. In addition, the weight ratio (P/R) of the chain alkyl acrylate compound (P) and the hydroxyl group-containing acrylate compound (R) may be included within a range formed by appropriately selecting the upper and lower limits listed above.

When the weight ratio (P/R) of the chain-type alkyl acrylate compound (P) and the hydroxyl group-containing acrylate compound (R) satisfies the above range, foaming or lifting between the lamination layers is prevented while providing adequate stability. can do.

In an example of the present application, the monomer having a surface tension of more than 30 mN/m at room temperature of the pressure-sensitive adhesive composition may include a cyclic alkyl acrylate compound.

The cyclic alkyl acrylate compound may have a surface tension of more than 30 mN/m, more than 31 mN/m, more than 32 mN/m, or more than 33 mN/m at room temperature.

In addition, the cyclic alkyl acrylate compound may have a glass transition temperature of 50 °C or higher, 55 °C or higher, 60 °C or higher, 65 °C or higher, 70 °C or higher, or 75 °C or higher.

The cyclic alkyl acrylate compound is sufficient as long as it is an acrylate compound that satisfies the above physical properties while having a cyclic alkyl group, for example, isobornyl (meth) acrylate, cyclohexyl (meth) acrylate, 3,3,5 - Trimethylcyclohexyl (meth) acrylate and t-butyl cyclohexyl (meth) acrylate, etc., but the type is not particularly limited.

In an example of the present application, the cyclic alkyl acrylate compound may be included in an amount of 10 to 100% by weight, 15 to 100% by weight, or 20 to 100% by weight based on the total weight of the monomer having a surface tension of more than 30 mN/m at room temperature.

In an example of the present application, a monomer having a surface tension of 30 mN/m or less at room temperature of the pressure-sensitive adhesive composition includes a hydroxyl group-containing acrylate compound, and a monomer having a surface tension of more than 30 mN/m at room temperature of the pressure-sensitive adhesive composition is a cyclic alkyl acryl It may contain a rate compound. Here, the hydroxyl group-containing acrylate compound and the cyclic alkyl acrylate compound are the same as described above.

In an example of the present application, the weight ratio (R/Q) of the hydroxyl group-containing acrylate compound (R) and the cyclic alkyl acrylate compound (Q) is 1.2 or more, 1.3 or more, 1.4 or more, 1.5 or more, 1.6 or more, It may be 1.7 or more or 1.8 or more, and may be 10 or less, 9 or less, 8 or less, 7 or less, or 6 or less. In addition, the weight ratio (R/Q) of the hydroxyl group-containing acrylate compound (R) and the cyclic alkyl acrylate compound (Q) may be included within a range formed by appropriately selecting the upper and lower limits listed above.

When the weight ratio (R/Q) of the hydroxy group-containing acrylate compound (R) and the cyclic alkyl acrylate compound (Q) satisfies the above range, bubbles are generated while satisfying basic physical properties such as durability and adhesion. Alternatively, it is possible to minimize the lifting phenomenon between the laminated layers.

In an example of the present application, the monomer having a surface tension of more than 30 mN/m at room temperature of the pressure-sensitive adhesive composition may include a cyclic ether group-containing acrylate compound.

The cyclic ether group-containing acrylate compound may have a surface tension of more than 30 mN/m, 30.5 mN/m or more, or 31 mN/m or more at room temperature.

In addition, the cyclic ether group-containing acrylate compound may have a glass transition temperature of 10 °C or less, 5 °C or less, 0 °C or less, -5 °C or less, or -10 °C or less.

The cyclic ether group-containing acrylate compound may include at least one compound represented by Formula 3 below.

[Formula 3]

In Formula 3, R ₃ may be hydrogen or a linear alkyl group having 1 to 20 carbon atoms. In addition, L ₃ and L ₄ may each independently be a single bond or a straight-chain alkylene group having 1 to 20 carbon atoms. In addition, L ₅ may be a single bond or a linear alkylene group having 1 to 8 carbon atoms. Also, Q may be an oxygen atom or a carbon atom.

In another example, in Formula 3, L ₃ and L ₄ are each independently 1 to 20 carbon atoms, 1 to 16 carbon atoms, 1 to 12 carbon atoms, 1 to 8 carbon atoms, 2 to 8 carbon atoms, 2 to 6 carbon atoms, or 2 to carbon atoms. 4 may be a straight-chain alkylene group. In addition, L ₅ may be a single bond or a linear alkylene group having 1 to 4 carbon atoms, for example, a single bond.

In addition, in Formula 3, L ₄ and The sum of carbon atoms present in L ₅ may be in the range of 1 to 8. The sum of the number of carbon atoms may be 7 or less, 6 or less, 5 or less, 4 or less, or 3 or less, or 1 or more, 2 or more, or 3 or more. L ₄ and The sum of carbon atoms of L ₅ is the number of carbon atoms in the alkylene group of L ₅ when L ₅ is an alkylene group, L ₄ is a single bond, L ₅ is an alkylene group, and alkyl of L ₅ when L ₄ is also an alkylene group It is the sum of the number of carbon atoms of the ren group and the number of carbon atoms of the alkylene group of L ₄ . In addition, when a substituent exists in the alkylene group, the number of carbon atoms present in the substituent is not included in the sum.

The compound represented by Formula 3 may have a surface tension of more than 30 mN/m, 30.5 mN/m or more, or 31 mN/m or more at room temperature.

In addition, the compound represented by Formula 3 may have a glass transition temperature of 10 °C or less, 5 °C or less, 0 °C or less, -5 °C or less, or -10 °C or less.

The compound represented by Formula 3 is oxiranyl (meth)acrylate, oxetanyl (meth)acrylate, tetrahydrofuranyl (meth)acrylate ( tetrahydrofuranyl (meth)acrylate), tetrahydro-2H-pyranyl (meth)acrylate, oxiranylmethyl (meth)acrylate, or glycy dill (meth)acrylate), oxetanylethyl (meth)acrylate, and tetrahydrofuranylmethyl (meth)acrylate (or tetrahydrofurfuryl (meth)acrylate) may be exemplified, and if the above-described physical properties are satisfied, the present invention is not particularly limited thereto.

In an example of the present application, when the cyclic ether group-containing acrylate compound is included in the pressure-sensitive adhesive composition, 35% by weight or more, 40% by weight or more, 45% by weight or more, based on the total weight of the monomer having a surface tension of more than 30 mN/m at room temperature or more, 50% by weight or more, 55% by weight or more, or 60% by weight or more, and in another example, the cyclic ether group-containing acrylate compound is 80% by weight based on the total weight of the monomer having a surface tension of more than 30 mN/m at room temperature It may be included in an amount of 75 wt% or less, 70 wt% or less, or 65 wt% or less. In addition, the cyclic ether group-containing acrylate compound may be included within the range formed by appropriately selecting the upper and lower limits listed above.

In an example of the present application, the monomer having a surface tension of more than 30 mN/m at room temperature of the pressure-sensitive adhesive composition may include an acrylate compound containing a cyclic ether group and a compound containing an acrylamide group.

The acrylamide group-containing compound may have a surface tension of more than 30 mN/m, more than 33 mN/m, more than 35 mN/m, or more than 37 mN/m at room temperature.

In addition, the acrylamide group-containing compound may have a glass transition temperature of 80 °C or higher, 90 °C or higher, 100 °C or higher, or 110 °C or higher.

The acrylamide group-containing compound is sufficient as long as it has an acrylamide group and satisfies the above physical properties, for example, N,N-dimethylacrylamide, N,N-methylethylacrylamide, N,N-diethylacrylamide, etc. However, the type is not particularly limited.

In an example of the present application, the acrylamide group-containing compound is used in an amount of 10 parts by weight or more, 15 parts by weight or more, 20 parts by weight or more, 25 parts by weight or more, or 30 parts by weight or more, based on 100 parts by weight of the cyclic ether group-containing acrylate compound. and may be included in an amount of 90 parts by weight or less, 80 parts by weight or less, 70 parts by weight or less, 60 parts by weight or less, 50 parts by weight or less, or 40 parts by weight or less in another example.

In an example of the present application, the pressure-sensitive adhesive composition may further include a photoinitiator for curing according to active energy rays. Here, the photoinitiator may be selected in consideration of a high absorption rate near the emission spectrum of the active energy ray and compatibility between the above-mentioned compounds, and the active energy ray is preferably an ultraviolet ray for rapid curing of the pressure-sensitive adhesive composition.

The photoinitiator may be at least one selected from the group consisting of a benzophenone-based initiator and an alpha-hydroxyketone-based initiator, and an alpha-hydroxyketone-based initiator is preferably selected. Specifically, the photoinitiator is 1-hydroxy-cyclohexylphenyl ketone, 2-hydroxy-4'-(2-hydroxyethoxy)-2-methyl among alpha-hydroxyketone initiators. At least one of propiophenone (2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone) and 1-hydroxy-1-methylethyl phenyl ketone may, but is not limited thereto.

In addition, the content of the photoinitiator is not particularly limited as long as the pressure-sensitive adhesive composition can be properly cured, but may be 0.01 wt% or more, 0.015 wt% or more, 0.02 wt% or more, or 0.025 wt% or more, based on the total weight of the pressure-sensitive adhesive composition, and other In an example, it may be 0.05 wt% or less, 0.04 wt% or less, or 0.03 wt% or less.

The pressure-sensitive adhesive composition including the photoinitiator may be cured according to active energy rays, and as described above, the active energy rays may be ultraviolet rays. The amount of light of the ultraviolet light may be 5 J/cm ² or more, 6 J/cm ² or more, 7 J/cm ² or more, 8 J/cm ² or more, 9 J/cm ² or more, or 10 J/cm ² or more, and other In an example 20 J/cm ² or less, 18 J/cm ² or less, 16 J/cm ² or less, 14 J/cm ² or less, or 12 J/cm ² or less. The curing time means the time until the pressure-sensitive adhesive composition is completely cured, and may vary depending on the thickness of the pressure-sensitive adhesive composition and the amount of ultraviolet light.

If necessary, the pressure-sensitive adhesive composition according to the present application may further include a leveling agent, a tackifier, a coupling agent, and a viscosity modifier. For example, a viscosity modifier, for example, a plasticizer, a thixotropy imparting agent, a diluent or a dispersing agent, etc. may be further included to increase or decrease the viscosity or to adjust the viscosity according to shear force. The thixotropic agent may adjust the viscosity according to the shear force of the pressure-sensitive adhesive composition. As the thixotropic agent that can be used, fumed silica, bentonite, and the like can be exemplified. Diluents or dispersants are generally used to lower the viscosity of the pressure-sensitive adhesive composition, and as long as they can exhibit the above action, various types of known in the art may be used without limitation.

In addition, the pressure-sensitive adhesive composition may include the configuration described above, and may be a solvent-based composition, an aqueous composition, or a solvent-free composition, but in consideration of the convenience of the manufacturing process, the solvent-free type may be appropriate.

In addition, the pressure-sensitive adhesive composition may be formed by mixing each of the components listed above, and if all necessary components can be included, the mixing order is not particularly limited.

In an example of the present application, the film may be a cured product of the above-described pressure-sensitive adhesive composition itself or may include a cured product of the pressure-sensitive adhesive composition. In addition, the film may have at least one of the following physical properties, and may be used as an optically clear adhesive (OCA).

In an example of the present application, the film may be used as an optical pressure-sensitive adhesive of a display product or a transparent electrode product to cover a defect located between the laminated layers of a display product or a transparent electrode product, thereby preventing the formation of bubbles. can

Each of the physical properties described below is independent, and any one property does not take precedence over the other properties, and the film may satisfy at least one or two or more of the properties described below. A film satisfying at least one or more of the following physical properties is caused by a combination of each component of the pressure-sensitive adhesive composition.

The film may have room temperature adhesive strength of 0.7 kg/inch or more, 0.75 kg/inch or more, or 0.8 kg/inch or more. The room temperature adhesive strength may be a value measured at room temperature by attaching the cured product of the adhesive composition to a PET (polyethylene terephthalate) film, and attaching the PET film to a peeling rate of 300 mm/min and a peeling angle of 180° using an adhesive force measuring device. have. In addition, at this time, the room temperature may mean about 25 ℃.

Further, the film may have a tensile modulus of at least 0.002 kgf/mm ² , at least 0.003 kgf/mm ² , at least 0.004 kgf/mm ² , at least 0.005 kgf/mm ² , or at least 0.006 kgf/mm ² , and in another example, 0.012 kgf /mm ² or less, 0.011 kgf/mm ² or less, 0.01 kgf/mm ² or less, or 0.009 kgf/mm ² or less. In addition, the tensile modulus of the film may be within a range formed by appropriately selecting the upper and lower limits listed above. In this case, the tensile rate may be defined as σ/ε, where σ is the tensile strength/cross-sectional area, and ε is the value/gage distance from the strain at which the film breaks to the gage distance (initial strain) can be

In addition, the film may have a storage modulus of 0.1 MPa or less at room temperature and a storage modulus of 0.055 MPa or less at 80°C. That is, the film may have a storage modulus of 0.1 MPa or less at room temperature and a storage modulus of 0.055 MPa or less at 80°C.

The film may have a storage modulus at room temperature of 0.1 MPa or less, 0.09 MPa or less, 0.08 MPa or less, 0.07 MPa or less, or 0.06 MPa or less, and in another example, the film has a room temperature storage modulus of 0.02 MPa or more, 0.025 MPa or more, 0.03 MPa or more , 0.035 MPa or more, 0.04 MPa or more, or 0.045 MPa or more. In addition, in this case, room temperature may mean about 25° C., and the room temperature storage modulus of the film may be within a range formed by appropriately selecting the upper and lower limits listed above.

In addition, the film may have an 80 °C storage modulus of 0.055 MPa or less, 0.0525 MPa or less, or 0.05 MPa or less, and in another example, the film may have an 80 °C storage modulus of 0.005 MPa or more, 0.0075 MPa or more, 0.01 MPa or more, or 0.0125 MPa or more. can In addition, the 80 ° C. storage modulus of the film may be within a range formed by appropriately selecting the upper and lower limits listed above.

When the tensile modulus and storage modulus of the film (at room temperature and 80° C.) satisfy the above ranges, excellent stability can be secured in evaluation of high temperature, low temperature, thermal shock, and high temperature/high humidity.

The film may have a wet-time of 60 seconds or less, measured according to the following wettability evaluation procedure.

[Wetting evaluation process]

1) Put the pressure-sensitive adhesive composition between the first light release film and the middle release film to have a constant thickness, and cure the pressure-sensitive adhesive composition to prepare a cured product sample (sample).

2) Remove the first light peel release film of the cured product sample, and apply the second light peel release film to one side of the cured product sample from which the first light peel release film is removed from the end of the cured product sample in the longitudinal direction 0.2 An evaluation sample is prepared by attaching it so as to overlap up to cm.

3) The evaluation sample is slightly placed on one side of the glass substrate so that the second light release film is in contact with the glass substrate, and the length from the end of the cured product sample in the portion where the second light release film is not attached and exposed. It is attached so as to be in contact with the glass substrate by 0.2 cm in the direction.

4) From the time when the exposed portion of the evaluation sample was attached so as to be in contact with the glass substrate from the tip to about 0.5 cm in the longitudinal direction, to the time when the exposed portion was in contact with the glass substrate from the tip to about 2 cm in the longitudinal direction Measure the elapsed time to the wet-time.

After the film is laminated with a polarizing plate, bubbles may not be generated even when exposed for about 500 hours at an amount of light of about 830 to 1,000 W/m ² .

At this time, the polarizing plate is not particularly limited as long as it is mainly used in the art, and a protective film, a tri-acetyl-cellulose (TAC) film, a polyvinyl alcohol (PVA) film, a TAC film, a pressure sensitive adhesives (PSA) film, and a release film It may have a laminated structure in the order of the films.

In an example of the present application, the display or the transparent electrode may include the aforementioned film as a pressure-sensitive adhesive layer. In addition, the display may include a transparent electrode including a film.

Since the display (or display product) or transparent electrode product (display including the transparent electrode) contains a film covering foreign substances, it satisfies the basic physical properties such as durability and adhesion, while preventing the occurrence of bubbles or lifting between the laminated layers. can be minimized Here, the display may be exemplified by a cathode ray tube (CRT) display, a plasma display panel (PDP), a liquid crystal display (LCD), a light emitting diode (LED) display, an organic emitting diode (OLED) display, and a quantum dot display. may, but is not limited thereto. In addition, the transparent electrode product may be exemplified by a display including a transparent electrode, and the transparent electrode is a transparent rigid substrate such as a glass substrate, PET (polyethylene terephthalate), PES (polyether sulfone), PEN (polyethylene naphthalate), etc. It refers to an electrode material having high conductivity and high transmittance in the visible region formed on a flexible substrate.

The present application may provide a pressure-sensitive adhesive composition that has excellent wettability and light resistance, and forms an optical pressure-sensitive adhesive capable of covering a step and a defect.

The present application can provide a pressure-sensitive adhesive composition that forms an optical pressure-sensitive adhesive that can minimize the occurrence of bubbles or the lifting phenomenon between the lamination layers while satisfying basic physical properties such as durability and adhesive strength.

In addition, the present application may provide a film capable of covering a foreign material (defect) located between the laminated layer of the display product or the transparent electrode product.

1 is a storage modulus (Storage Modulus), loss modulus (Loss Modulus) and tangent value (tan δ) of a cured product of the pressure-sensitive adhesive composition according to Example 1 according to temperature in a temperature range of -50 ℃ to 120 ℃ It is a graph.
2 is a storage modulus (Storage Modulus), loss modulus (Loss Modulus) and tangent value (tan δ) of the cured product of the pressure-sensitive adhesive composition according to Example 2 according to temperature in the temperature range of -50 ℃ to 120 ℃ It is a graph.
3 is a storage modulus (Storage Modulus), loss modulus (Loss Modulus) and tangent value (tan δ) of the cured product of the pressure-sensitive adhesive composition according to Comparative Example 1 according to temperature in a temperature range of -50 ℃ to 120 ℃ It is a graph.
4 is a storage modulus (Storage Modulus), loss modulus (Loss Modulus) and tangent value (tan δ) of the cured product of the pressure-sensitive adhesive composition according to Comparative Example 3 according to temperature in the temperature range of -50 ℃ to 120 ℃ It is a graph.
5 is a photograph showing between the glass substrate and the cured pressure-sensitive adhesive composition after light resistance evaluation for the pressure-sensitive adhesive composition according to Example 1.
6 is a photograph showing between the glass substrate and the cured pressure-sensitive adhesive composition after light resistance evaluation for the pressure-sensitive adhesive composition according to Example 2.
7 is a photograph showing between the glass substrate and the cured pressure-sensitive adhesive composition after light resistance evaluation for the pressure-sensitive adhesive composition according to Comparative Example 1.
8 is a photograph showing between the glass substrate and the cured pressure-sensitive adhesive composition after light resistance evaluation for the pressure-sensitive adhesive composition according to Comparative Example 2.
9 is a photograph showing between the glass substrate and the cured pressure-sensitive adhesive composition after light resistance evaluation of the pressure-sensitive adhesive composition according to Comparative Example 3.
10 is a photograph showing between the glass substrate and the cured pressure-sensitive adhesive composition after light resistance evaluation for the pressure-sensitive adhesive composition according to Comparative Example 4.

Hereinafter, the present application will be described with reference to Examples and Comparative Examples, but the scope of the present application is not limited by the contents presented below.

<Method of measuring physical properties>

1. Tensile modulus measurement method

The pressure-sensitive adhesive composition was placed between the release films to have a thickness of 200 μm and cured through a photocuring method at an amount of light of 9 to 11 J/cm ² using an ultraviolet lamp, and a width of 2.5 cm and a length of 7 cm (a gage distance of 3.5 cm) ) and cut to a thickness of 200 μm to prepare a measurement sample. Thereafter, the measurement sample is deformed until fractured in the longitudinal direction at a rate of 300 mm/min, and at this time, the strain (strain (Δl), unit: mm) and tensile strength (tensile stress (F), unit : kgf) to calculate the tensile modulus (unit: kgf/mm ² ).

Here, the tensile modulus was defined as σ/ε. σ is defined as F/A, where F (tensile stress) is the tensile strength and A is the cross-sectional area. ε was defined as Δl/l, Δl is the difference between the gage distance (initial strain) value in the strain at which the measurement sample failed, and l is the gage distance.

The pressure-sensitive adhesive composition was placed between the light release film and the jungbak release film to have a thickness of 200 μm and cured through a photocuring method using an ultraviolet lamp at a light quantity of 9 to 11 J/cm ² . After curing was completed, it was cut to a width of 2.5 cm, a length of 11 cm, and a thickness of 325 μm to prepare a cured product sample.

The light release film of the cured product sample was removed, and a PET (polyethylene terephthalate) film having a width of 2.5 cm or more, a length of 25 cm, and a thickness of 75 μm was attached to the surface from which the light release film was removed. The cured product sample to which the PET film was attached was cut to have a width of 2.5 cm, a length of 25 cm, and a thickness of 350 μm.

Thereafter, the Jungbak release film was removed from the cut cured product sample, and the Jungbak release film was removed on one side of a glass substrate (Corning Corporation, product name: Eagle XG glass) having a width of 12.5 cm, a length of 12.5 cm, and a thickness of 700 μm. The cut cured product sample was attached so that the finished surface was in contact. A roller of about 2 kg was used to attach the glass substrate and the cut cured product sample, and after attachment, it was left at room temperature for about 30 minutes.

Thereafter, the PET film was held through an adhesive force measuring device (Daewon Tech, model name: TW-D2000) and peeled at room temperature at a peeling rate of 300 mm/min and a peeling angle of 180° to measure the adhesive force. The measured adhesive force was expressed as an average value through repeated experiments.

3. Wetability evaluation method - Wet-time measurement

Hereinafter, the wettability evaluation process was carried out at room temperature and in a habitual environment.

The pressure-sensitive adhesive composition was placed between the first light release film having a width of 42.0 cm, a length of 1,000 cm and a thickness of 50 μm and a jungbak release film having a width of 42.0 cm, a length of 1,000 cm and a thickness of 75 μm to have a thickness of 200 μm. Thereafter, the pressure-sensitive adhesive composition was cured by curing through a photocuring method at an amount of light of 9 to 11 J/cm ² using an ultraviolet lamp, and cut to a width of 2 cm, a length of 4 cm and a thickness of 325 μm to obtain a cured sample (sample). ) was prepared.

Remove the first light release release film, and apply a second light release release film having a width of 2.0 cm, a length of 4.0 cm and a thickness of 50 μm on one side of the cured product sample from which the first light release release film is removed. An evaluation sample was prepared by attaching it to overlap up to 0.2 cm in the longitudinal direction from the end. That is, the evaluation sample has a heavy peel release film attached to all one side of the cured product sample, and a second light peel release film is attached to the other side by overlapping up to 0.2 cm in the longitudinal direction from the end of the cured product sample, and does not overlap. The non-exposed part has a structure in which the cured product sample is exposed.

The evaluation sample was slightly placed on one side of a glass substrate (Corning Corporation, product name: Eagle XG glass) cut to a width of 12.5 cm, a length of 12.5 cm, and a thickness of 700 μm so that the second light-peelable release film was in contact with the glass substrate. .

Then, the evaluation sample was attached so as to be in contact with the glass substrate from the end of the exposed cured product sample to 0.2 cm in the longitudinal direction. That is, the exposed cured product sample of the evaluation sample was attached so as to be in contact with the glass substrate from the tip to about 0.2 cm.

The elapsed time from the point at which the exposed portion of the evaluation sample is attached so as to be in contact with the glass substrate from the tip to about 0.5 cm in the longitudinal direction, to the time when the exposed portion is in contact with the glass substrate from the tip to the length of 2 cm in the longitudinal direction Time was measured as wet-time.

Wettability was evaluated according to the following criteria based on the measured elapsed time.

PASS: Elapsed wet-time is less than 60 seconds

NG: Elapsed wet-time greater than 60 seconds

4. How to evaluate light fastness

The pressure-sensitive adhesive composition was placed between the light release film and the jungbak release film to have a thickness of 200 μm and cured through a photocuring method using an ultraviolet lamp at a light quantity of 9 to 11 J/cm ² . After curing was completed, it was cut to a width of 10 cm, a length of 10 cm, and a thickness of 325 μm to prepare a cured product sample.

Remove the light peeling release film of the cured product sample, and the side from which the light peeling release film is removed is in contact with one side of a glass substrate (Corning Corporation, product name: Eagle XG glass) having a width of 10 cm, a length of 10 cm, and a thickness of 700 μm. The cured product sample was attached as much as possible. A roller of about 2 kg was used to attach the glass substrate and the cured product sample.

10 cm wide, 10 cm long and A polarizing plate having a thickness of 258 μm was prepared, and the protective film was removed.

Remove the Jungbak release film of the cured product sample attached to the glass substrate, and laminate the TAC film side of the polarizing plate from which the protective film is removed and the surface from which the Jungbak release film is removed using a roller to prepare a laminated sample did.

Thereafter, in a vacuum laminating equipment (MRK company, product name: M-Tool vacuum laminator & autoclave) that can create a vacuum environment of about 97 kPa, the glass substrate of the laminated sample is placed facing the floor, and the release film of the polarizing plate is removed. The PSA film was exposed. A glass substrate (Corning Corporation, product name: Eagle XG glass) having a width of 10 cm, a length of 10 cm, and a thickness of 700 μm is placed on the exposed PSA film and left at a temperature of about 40° C. for about 30 seconds, the glass substrate and the polarizing plate The laminated sample from which the release film was removed was laminated.

That is, the laminated sample has a structure in which a glass substrate, a polarizing plate from which a protective film and a release film are removed, a cured pressure-sensitive adhesive composition, and a glass substrate are sequentially laminated.

After lamination, autoclave was performed at a temperature of about 50° C. and a pressure of about 0.5 MPa for about 15 minutes. Thereafter, using a light generating device (Philips, product name: Arenavision MVF403), exposure was carried out for about 500 hours at an amount of light of about 830 to 1,000 W/m ² , and at this time, the light generated by the light generating device was laminated. of the glass substrate was the first to contact.

Thereafter, it was confirmed whether bubbles were generated between the glass substrate and the cured pressure-sensitive adhesive composition, and light resistance was evaluated according to the following criteria.

PASS: No air bubbles

NG: Bubbles are generated

5. How to measure storage modulus according to temperature

The pressure-sensitive adhesive composition was placed between the release films to have a thickness of 200 μm and cured through a photocuring method at an amount of light of 9 to 11 J/cm ² using an ultraviolet lamp to form a cured product. The cured products were attached to each other and manufactured to have a thickness of 1 mm. The cured product was cut to have a diameter of 8 mm and a thickness of 1 mm to prepare a measurement sample in the form of a disk.

Storage elastic modulus was measured in a temperature range of -50 °C to 120 °C while applying a 1% strain and a rotation speed of 1 Hz to the measurement sample using a rotational rheometer (TA, product name: ARES-G2). did. When the temperature was raised from -50°C to 120°C, the rate of temperature increase was 5°C per minute.

In addition, the storage modulus at room temperature was based on the storage modulus of 25 °C.

Example 1

The weight ratio of the monomer (T1) having a glass transition temperature (T _g ) of more than 10 °C and the monomer (T2) having a glass transition temperature of 10 °C or less is 15:85 (T1:T2), and the surface tension at room temperature is 30 mN/m A pressure-sensitive adhesive composition was prepared such that the weight ratio of the excess monomer (S1) and the monomer (S2) having a surface tension of 30 mN/m or less at room temperature was 15:85 (S1:S2).

Specifically, isodecyl acrylate (IDA, isodecyl acrylate), isobornyl acrylate (IBOA, isobornyl acrylate), 2-hydroxyethyl acrylate (2-HEA, 2-hydroxyethyl acrylate) and butyl acrylate (BA, butyl acrylate) was uniformly mixed in a weight ratio of 24:15:27:34 (IDA:IBOA:2-HEA:BA), and 0.03 parts by weight of a photoinitiator (Ciba Corporation, IRGCURE 184) based on 100 parts by weight of the mixture was added. was added to prepare a pressure-sensitive adhesive composition.

Example 2

The weight ratio of the monomer (T1) having a glass transition temperature (Tg) of more than 10 °C and the monomer (T2) having a glass transition temperature of 10 °C or less is 7:93 (T1: T2), and the surface tension at room temperature is more than 30 mN/m A pressure-sensitive adhesive composition was prepared so that the weight ratio of the phosphorus monomer (S1) and the monomer (S2) having a surface tension of 30 mN/m or less at room temperature was 18:82 (S1:S2).

Specifically, butyl acrylate (BA, butyl acrylate), isobornyl acrylate (IBOA, isobornyl acrylate), tetrahydrofurfuryl acrylate (THFA, tetrahydrofurfuryl acrylate), 2-ethylhexyl acrylate (2-EHA, 2 -ethylhexyl acrylate) and 2-hydroxyethyl acrylate (2-HEA, 2-hydroxyethyl acrylate) in a weight ratio of 20:7:11:34:28 (BA:IBOA:THFA:2-EHA:2-HEA) was uniformly mixed, and 0.03 parts by weight of a photoinitiator (Ciba, IRGCURE 184) was added to 100 parts by weight of the mixture to prepare a pressure-sensitive adhesive composition.

Example 3

The weight ratio of the monomer (T1) having a glass transition temperature (Tg) of more than 10°C and the monomer (T2) having a glass transition temperature of 10°C or less is 2:98 (T1:T2), and the surface tension at room temperature is more than 30 mN/m A pressure-sensitive adhesive composition was prepared such that the weight ratio of the phosphorus monomer (S1) and the monomer (S2) having a surface tension of 30 mN/m or less at room temperature was 5:95 (S1:S2).

Specifically, 2-ethylhexyl acrylate (2-EHA), 2-hydroxyethyl acrylate (2-HEA), N,N-dimethyl acrylamide (DMAA), isobronyl acrylate (IBOA), and tetrahydro Furfuryl acrylate (THFA) was uniformly mixed in a weight ratio of 90:5:1:1:3 (2-EHA:2-HEA:DMAA:IBOA:THFA), and 0.03 parts by weight based on 100 parts by weight of the mixture. A photo-initiator (Ciba, IRGCURE 184) was added to prepare a pressure-sensitive adhesive composition.

Comparative Example 1

The weight ratio of the monomer (T1) having a glass transition temperature (Tg) of more than 10°C and the monomer (T2) having a glass transition temperature of 10°C or less is 19:81 (T1:T2), and the surface tension at room temperature is more than 30 mN/m A pressure-sensitive adhesive composition was prepared such that the weight ratio of the phosphorus monomer (S1) and the monomer (S2) having a surface tension of 30 mN/m or less at room temperature was 24:76 (S1:S2). Specifically, 2-ethylhexyl acrylate (2-EHA), 2-hydroxyethyl acrylate (2-HEA), N,N-dimethyl acrylamide (DMAA), isostearyl acrylate (ISTA), isobromide Neyl acrylate (IBOA) and tetrahydrofurfuryl acrylate (THFA) were homogeneously in a weight ratio of 39:17:5:20:14:5 (2-EHA:2-HEA:DMAA:ISTA:IBOA:THFA) A pressure-sensitive adhesive composition was prepared by adding 0.18 parts by weight of a photoinitiator (Ciba, IRGCURE 184) based on 100 parts by weight of the mixture.

Comparative Example 2

The weight ratio of the monomer (T1) having a glass transition temperature (Tg) of more than 10 °C and the monomer (T2) having a glass transition temperature of 10 °C or less is 24:76 (T1:T2), and the surface tension at room temperature is more than 30 mN/m A pressure-sensitive adhesive composition was prepared so that the weight ratio of the phosphorus monomer (S1) and the monomer (S2) having a surface tension of 30 mN/m or less at room temperature was 37:63 (S1:S2).

Specifically, 2-ethylhexyl acrylate (2-EHA), 2-hydroxyethyl acrylate (2-HEA), N,N-dimethyl acrylamide (DMAA), isostearyl acrylate (ISTA), isobromide Neyl acrylate (IBOA) and tetrahydrofurfuryl acrylate (THFA) were homogeneously in a weight ratio of 33:14:12:17:12:12 (2-EHA:2-HEA:DMAA:ISTA:IBOA:THFA) A pressure-sensitive adhesive composition was prepared by adding 0.15 parts by weight of a photoinitiator (Ciba, IRGCURE 184) based on 100 parts by weight of the mixture.

Comparative Example 3

The weight ratio of the monomer (T1) having a glass transition temperature (Tg) of more than 10°C and the monomer (T2) having a glass transition temperature of 10°C or less is 19:81 (T1:T2), and the surface tension at room temperature is more than 30 mN/m A pressure-sensitive adhesive composition was prepared such that the weight ratio of the phosphorus monomer (S1) and the monomer (S2) having a surface tension of 30 mN/m or less at room temperature was 24:76 (S1:S2).

Specifically, 2-ethylhexyl acrylate (2-EHA), 2-hydroxyethyl acrylate (2-HEA), N,N-dimethyl acrylamide (DMAA), isostearyl acrylate (ISTA), isobromide Neyl acrylate (IBOA) and tetrahydrofurfuryl acrylate (THFA) were homogeneously in a weight ratio of 39:17:5:20:14:5 (2-EHA:2-HEA:DMAA:ISTA:IBOA:THFA) and 0.03 parts by weight of a photoinitiator (Ciba, IRGCURE 184) based on 100 parts by weight of the mixture was added to prepare a pressure-sensitive adhesive composition.

Comparative Example 4

The weight ratio of the monomer (T1) having a glass transition temperature (Tg) of more than 10 °C and the monomer (T2) having a glass transition temperature of 10 °C or less is 24:76 (T1:T2), and the surface tension at room temperature is more than 30 mN/m A pressure-sensitive adhesive composition was prepared such that the weight ratio of the phosphorus monomer (S1) and the monomer (S2) having a surface tension of 30 mN/m or less at room temperature was 30:70 (S1:S2).

Specifically, 2-ethylhexyl acrylate (2-EHA), 2-hydroxyethyl acrylate (2-HEA), N,N-dimethyl acrylamide (DMAA), isobronyl acrylate (IBOA), and tetrahydro Furfuryl acrylate (THFA) was uniformly mixed in a weight ratio of 49:21:6:18:6 (2-EHA:2-HEA:DMAA:IBOA:THFA), and 0.03 parts by weight based on 100 parts by weight of the mixture A photo-initiator (Ciba, IRGCURE 184) was added to prepare a pressure-sensitive adhesive composition.

Physical properties measured for the Examples and Comparative Examples are as shown in Table 1 below.

division Glass transition temperature (℃) Room temperature surface tension (mN/m) Tensile modulus (kgf/mm ² ) Room temperature storage modulus (MPa) 80 ℃ storage modulus (MPa) Adhesion (kg/inch) Wet-time (seconds) Light fastness evaluation Example 1 -35 29.3 0.009 0.046 0.052 0.8 PASS
30-50 PASS Example 2 -36 27 0.006 0.060 0.048 One PASS
20-40 PASS Example 3 -48 25.7 0.005 0.025 0.015 0.9 PASS
10-20 PASS Comparative Example 1 -17 34.6 0.021 0.156 0.070 3.6 NG
>300 NG Comparative Example 2 -12 32.8 0.050 0.314 0.056 5.2 NG
>300 NG Comparative Example 3 -20 35.4 0.021 0.159 0.088 2.7 NG
>300 NG Comparative Example 4 -32 31.2 0.012 0.072 0.070 One NG
60-100 NG

Referring to Table 1, Examples 1 to 3 showed a glass transition temperature of -25 °C or less, and a surface tension of 30 mN/m or less at room temperature.

On the other hand, Comparative Examples 1 to 3 did not satisfy the glass transition temperature of -25 ° C or less, and Comparative Examples 1 to 4 showed a surface tension of more than 30 mN/m at room temperature.

In addition, referring to Table 1, Examples 1 to 3 had a tensile rate within the range of 0.002 to 0.012 kgf/mm ² , but Comparative Examples 1 to 4 had a tensile rate of 0.012 kgf/mm ² or more.

In addition, referring to Table 1, Examples 1 to 3 all showed that the storage modulus at room temperature was 0.1 MPa or less and the storage modulus at 80°C was all 0.055 MPa or less. 1 and 2, the storage modulus values according to the temperature of Examples 1 and 2 can be confirmed.

On the other hand, in Comparative Examples 1 to 3, all of the storage modulus at room temperature exhibited a value greater than 0.1 MPa, and all of the storage modulus at 80° C. showed a value greater than 0.055 MPa. Referring to FIGS. 3 and 4 , the storage modulus values according to the temperature of Comparative Examples 1 and 3 can be confirmed.

In addition, referring to Table 1, Examples 1 to 3 had a wet-time of 60 seconds or less, and all of them were PASS in the wettability evaluation. On the other hand, Comparative Examples 1 to 4 showed a value greater than 60 seconds for wetting time, indicating NG in wettability evaluation.

In addition, referring to Table 1, Examples 1 to 3 did not generate bubbles in the light resistance evaluation, so all of them were PASS. 5 and 6 show the light resistance evaluation results of Examples 1 and 2. Referring to FIGS. 5 and 6 , it can be seen that bubbles are not generated even if there is a defect.

On the other hand, in Comparative Examples 1 to 4, bubbles were generated in the light resistance evaluation, and all of them were NG. 7 to 10 show the light resistance evaluation results of Comparative Examples 1-4. Referring to FIGS. 7 to 10 , it can be seen that bubbles are generated around a defect.

Claims (22)

A copolymer obtained by copolymerizing two or more monomers,
The monomer includes a monomer having a surface tension of more than 30 mN/m at room temperature and a monomer having a surface tension of 30 mN/m or less at room temperature,
The surface tension of the copolymer at room temperature is 30 mN / m or less pressure-sensitive adhesive composition.
The pressure-sensitive adhesive composition according to claim 1, wherein the monomer satisfies the following general formula 1:
[General formula 1]
3 ≤ A/B×100 ≤ 30
In General Formula 1, A represents the weight of a monomer having a surface tension of more than 30 mN/m at room temperature, and B represents the weight of a monomer having a surface tension of 30 mN/m or less at room temperature.
According to claim 1, wherein the monomer comprises a monomer having a glass transition temperature of more than 10 ℃ and a monomer having a glass transition temperature of 10 ℃ or less,
The glass transition temperature of the copolymer is -25 ℃ or less pressure-sensitive adhesive composition.
The pressure-sensitive adhesive composition according to claim 3, wherein the monomer satisfies the following general formula 2:
[General formula 2]
1 ≤ C/D×100 ≤ 22
In General Formula 2, C represents the weight of a monomer having a glass transition temperature of more than 10° C., and D represents the weight of a monomer having a glass transition temperature of 10° C. or less.
The pressure-sensitive adhesive composition according to claim 1, wherein the monomer having a surface tension of 30 mN/m or less at room temperature comprises a chain-type alkyl acrylate compound.
The pressure-sensitive adhesive composition according to claim 5, wherein the chain-type alkyl acrylate compound has a glass transition temperature of -20°C or less.
The pressure-sensitive adhesive composition according to claim 5, wherein the chain alkyl acrylate compound comprises at least one compound represented by the following formula (1):
[Formula 1]

In Formula 1,
L ₁ is a linear alkylene group having 1 to 14 carbon atoms or a branched alkylene group having 2 to 14 carbon atoms,
R ₁ and R ₂ are each independently hydrogen, a linear alkyl group having 1 to 6 carbon atoms, or a branched chain alkyl group having 2 to 6 carbon atoms.
The pressure-sensitive adhesive composition according to claim 1, wherein the monomer having a surface tension of 30 mN/m or less at room temperature comprises a hydroxyl group-containing acrylate compound.
The pressure-sensitive adhesive composition according to claim 8, wherein the hydroxyl group-containing acrylate compound has a glass transition temperature of 0° C. or less.
The pressure-sensitive adhesive composition according to claim 8, wherein the hydroxyl group-containing acrylate compound comprises at least one compound represented by the following formula (2):
[Formula 2]

In Formula 2,
L ₂ is a linear alkylene group having 1 to 10 carbon atoms, a branched chain alkylene group having 2 to 10 carbon atoms, a linear or branched alkenylene group having 2 to 10 carbon atoms, or a linear or branched chain having 2 to 10 carbon atoms. is an alkynylene group of
The pressure-sensitive adhesive composition according to claim 1, wherein the monomer having a surface tension of more than 30 mN/m at room temperature comprises a cyclic alkyl acrylate compound.
The pressure-sensitive adhesive composition according to claim 11, wherein the cyclic alkyl acrylate compound has a glass transition temperature of 50°C or higher.
11. The method according to any one of claims 8 to 10, wherein the monomer having a surface tension of more than 30 mN/m at room temperature comprises a cyclic alkyl acrylate compound,
The weight ratio (R/Q) of the hydroxyl group-containing acrylate compound (R) and the cyclic alkyl acrylate compound (Q) is in the range of 1.2 to 10.
The pressure-sensitive adhesive composition according to claim 1, wherein the monomer having a surface tension of more than 30 mN/m at room temperature comprises an acrylate compound containing a cyclic ether group.
The pressure-sensitive adhesive composition according to claim 14, wherein the cyclic ether group-containing acrylate compound has a glass transition temperature of 10°C or less.
15. The pressure-sensitive adhesive composition according to claim 14, wherein the cyclic ether group-containing acrylate compound comprises at least one compound represented by the following formula (3):
[Formula 3]

In Formula 3,
R ₃ is hydrogen or a linear alkyl group having 1 to 20 carbon atoms,
L ₃ and L ₄ are each independently a single bond or a straight-chain alkylene group having 1 to 20 carbon atoms,
L ₅ is a single bond or a linear alkylene group having 1 to 8 carbon atoms,
Q is an oxygen atom or a carbon atom.
A film comprising a cured product of the pressure-sensitive adhesive composition according to claim 1 .
The film according to claim 17, wherein the film has a room temperature adhesive force of 0.7 kg/inch or more, a tensile modulus in the range of 0.002 to 0.012 kgf/mm ² , or a room temperature storage modulus of 0.1 MPa or less and an 80°C storage modulus of 0.055 MPa or less. .
A copolymer obtained by copolymerizing two or more monomers,
The surface tension of the copolymer at room temperature is 30 mN/m or less, and the pressure-sensitive adhesive composition having a glass transition temperature of -25°C or less.
The method of claim 19, wherein the monomer is a first monomer comprising a monomer having a surface tension of more than 30 mN/m at room temperature and a monomer having a surface tension of 30 mN/m or less at room temperature; or at least one of a second monomer including a monomer having a glass transition temperature of more than 10 °C and a monomer having a glass transition temperature of 10 °C or less,
The pressure-sensitive adhesive composition in which the first monomer satisfies the following general formula 1, and the second monomer satisfies the following general formula 2:
[General formula 1]
3 ≤ A/B×100 ≤ 30
[General formula 2]
1 ≤ C/D×100 ≤ 22
In general formula 1, A represents the weight of a monomer having a surface tension of more than 30 mN/m at room temperature, B represents the weight of a monomer having a surface tension of 30 mN/m or less at room temperature,
In General Formula 2, C represents the weight of a monomer having a glass transition temperature of more than 10° C., and D represents the weight of a monomer having a glass transition temperature of 10° C. or less.
The pressure-sensitive adhesive composition according to claim 20, wherein the monomer having a glass transition temperature of more than 10°C and a surface tension of more than 30 mN/m at room temperature is included in the range of 0.5 to 18 wt% based on the total weight of the monomer.
The method of claim 21, wherein the glass transition temperature is 10 ℃ or less and the surface tension at room temperature 30 mN / m or less of the monomer is 450 to 100 parts by weight of the monomer having a glass transition temperature of 10 ° C A pressure-sensitive adhesive composition included in the range of 5,500 parts by weight.

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