KR102329318B1 - Adhesive sheet, optical member and display device using the same - Google Patents

Abstract

The present invention has a moisture permeability of 100 g/m ² day or more, an adhesive force to soda glass of 25 N/25 mm or more, and a decrease rate of the adhesive force when left for 120 hours under a condition of 23° C. and 95 RH%. The present invention relates to a pressure-sensitive adhesive sheet having excellent cleaning power and easy reuse of an adherend, an optical member including the same, and an image display device.

Description

Adhesive sheet, optical member and image display device including same {ADHESIVE SHEET, OPTICAL MEMBER AND DISPLAY DEVICE USING THE SAME}

The present invention relates to an adhesive sheet, an optical member including the same, and an image display device.

DESCRIPTION OF RELATED ART The field|area of portable electronic devices, such as a mobile phone and a portable information terminal device, WHEREIN: The adhesive is used for fixing between various members. As the adhesive, optically clear resin (OCR), which is a liquid adhesive, and optically clear adhesive (OCA), which is a sheet-type adhesive, are used.

In particular, OCR-type pressure-sensitive adhesives have been used in the manufacture of various electronic devices because they are easy to remove using ethanol, etc. In the case of an adhesive, there is a problem that the adhesive strength is insufficient to be applied to a flexible image display device, which is recently in the spotlight.

However, in the case of the OCA-type pressure-sensitive adhesive as described above, while the adhesive strength is improved, the peeling force is lowered thereby, there is a problem in that it is difficult to remove the pressure-sensitive adhesive composition, and there is a problem that it is impossible to reuse the adherend to which the pressure-sensitive adhesive is attached. When a problem occurs, the members such as the substrate cannot be reused and are discarded.

In order to supplement this point, Korean Patent Laid-Open No. 10-2014-0008664 discloses a pressure-sensitive adhesive composition comprising 25 parts by weight or more of a hydrophilic functional group-containing monomer with respect to 100 parts by weight of a (meth)acrylic acid ester-based monomer, Korean Patent Laid-Open No. 10-2016-0011785 discloses an acrylic photocurable resin formed by polymerization of a monomer component containing two different types of (meth)acrylic ester monomers, and one of the two types of (meth)acrylic ester monomers. The species is a tackifying monomer, and the pressure-sensitive adhesive composition is described in which the tackifying monomer is a C6-C20 alicyclic condensed ring or a fused ring-containing acrylate.

The pressure-sensitive adhesive compositions as described above each tried to improve the peeling force through the above-described composition, but the peeling strength is not sufficient, so that when applied to some glasses, the pressure-sensitive adhesive is not completely removed, and durability is also reduced.

Republic of Korea Patent Publication No. 10-2014-0008664 (2014.01.22.) Republic of Korea Patent Publication No. 10-2016-0011785 (2016.02.02.)

The present invention is to solve the above problems, and it is an object of the present invention to provide a pressure-sensitive adhesive sheet that is easy to clean using water, an optical member and an image display device including the same, because moisture permeability and adhesion decrease rate by moisture are improved. .

The adhesive sheet of the present invention for achieving the above object has a moisture permeability of 100 g/m ² day or more, an adhesive strength to soda glass of 25 N/25 mm or more, and the adhesive strength when left for 120 hours under the conditions of 23° C. and 95 RH% It is characterized in that the reduction rate of 50% or more.

In addition, the optical member of the present invention is characterized in that it includes the above-described pressure-sensitive adhesive sheet.

In addition, the image display apparatus of the present invention is characterized in that it includes the above-described optical member.

The adhesive sheet of the present invention has an advantage in that it is excellent in moisture permeability and can be easily washed with water.

In addition, the optical member of the present invention has an advantage that can be reused by including the above-described pressure-sensitive adhesive sheet.

In addition, the image display apparatus of the present invention has the same advantages as described above by including the above-described optical member.

In the present invention, when a part "includes" a certain component, this means that other components may be further included rather than excluding other components unless otherwise stated.

Hereinafter, the present invention will be described in more detail.

< adhesive layer >

The pressure-sensitive adhesive sheet according to an embodiment of the present invention has a moisture permeability of 100 g/m ² day or more, an adhesive strength to soda glass of 25 N/25 mm or more, and a decrease rate of the adhesive strength when left for 120 hours under the conditions of 23° C. and 95 RH% When this amount is 50% or more, there is an advantage in that the cleaning power by water is excellent and the reuse of the adherend is easy.

In this case, the adherend may mean all optical members that can be bonded through the pressure-sensitive adhesive sheet in the image display device, and may be, for example, glass or plastic, but this is only an example and is limited thereto. it's not going to be

The pressure-sensitive adhesive sheet of the present invention may be manufactured by using the pressure-sensitive adhesive composition of any configuration as long as it can satisfy the conditions of the pressure-sensitive adhesive sheet of the present invention as described above. It may include cargo.

adhesive composition

acrylic polymer

According to an embodiment of the present invention, the pressure-sensitive adhesive composition is a repeating unit derived from an acrylic monomer containing a _{C 1} to C _{20 linear, branched or alicyclic alkyl group;} and a repeating unit derived from an amide-based monomer; and may include a polymerized acrylic polymer.

The repeating unit derived from the acrylic monomer may improve wettability when bonding to an adherend while being present in the acrylic polymer, thereby improving adhesion and improving durability.

The acrylic monomer may contain a C ₁ to C ₂₀ straight chain, branched chain or alicyclic alkyl group _{as described above, and preferably contains a C 6} to C ₁₀ straight chain, branched chain or alicyclic alkyl group. When the carbon number is satisfied, there is an advantage of excellent adhesion. In this case, the acrylic monomer may be an alkyl (meth)acrylate containing a straight-chain, branched-chain or alicyclic alkyl group that specifically satisfies the carbon number.

The alkyl (meth) acrylate having the straight-chain 　 or branched alkyl group is not particularly limited, and examples thereof include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylic. rate, butyl (meth)acrylate, isobutyl (meth)acrylate, s-butyl (meth)acrylate, t-butyl (meth)acrylate, pentyl (meth)acrylate, isopentyl (meth)acrylate, Hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, nonyl (meth) acrylate, isononyl (meth) ) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate, undecyl (meth) acrylate, dodecyl (meth) acrylate, tridecyl (meth) acrylate, tetradecyl (meth) acrylate , pentadecyl (meth) acrylate, hexadecyl (meth) acrylate, heptadecyl (meth) acrylate, octadecyl (meth) acrylate, nonadecyl (meth) acrylate and eicosyl (meth) acrylate, etc. can be heard

The alkyl (meth) acrylate containing the alicyclic alkyl group is trimethylcyclohexyl acrylate, t-butyl cyclohexyl acrylate, dicyclopentadiene (meth) acrylate, trimethylcyclohexyl methacrylate, cyclohexyl Methacrylate, isobornyl methacrylate, 2-ethylhexyl methacrylate, tetrahydrofurfuryl methacrylate, 3,3,5-trimethylcyclohexyl methacrylate, 4-t-butyl cyclohexyl methacrylate and the like, but is not limited thereto.

According to an embodiment of the present invention, the repeating unit derived from the acrylic monomer may be included in an amount of 70 to 90% by weight, preferably 80 to 90% by weight, based on 100% by weight of the total acrylic polymer.

The amide-based monomer may be used without particular limitation as long as it is used in the art. For example, (meth)acrylamide, N,N-dimethyl (meth)acrylamide, N-butyl (meth)acrylamide, N-methylol (meth)acrylamide, N-methylolpropane (meth)acrylamide -amide, N-methoxymethyl (meth) acrylamide, and N-butoxymethyl (meth) acrylamide, and the like, but are not limited thereto.

According to one embodiment of the present invention, the repeating unit derived from the amide-based monomer may be included in an amount of 10 wt% or more based on 100 wt% of the total acrylic polymer. When the content of the amide-based monomer satisfies the above range, water solubility may be improved to improve moisture permeability, and thereby, there is an advantage in that cleaning power by water may be improved.

The above-mentioned acrylic polymer and amide monomer may be prepared and used as acrylic syrup by further including a photopolymerization initiator, and the specific details of the photopolymerization initiator included in this case are the same as the photopolymerization initiator to be described later, and the same type may be used. It is also possible to use different ones.

According to one embodiment of the present invention, the pressure-sensitive adhesive composition may further include one or more selected from the group consisting of a photopolymerization initiator and additives.

light curing initiator

The photopolymerization initiator serves to cure the pressure-sensitive adhesive composition including the same, and as long as it is used as a photopolymerization initiator in the art, it can be used without particular limitation, and is not particularly limited in the present invention.

Specifically, benzoin ether-based photopolymerization initiator, acetophenone-based photopolymerization initiator, α-ketol-based photopolymerization initiator, aromatic sulfonyl chloride-based photopolymerization initiator, photoactive oxime-based photopolymerization initiator, benzoin-based photopolymerization initiator, benzyl-based photopolymerization initiator, benzophene A non-type photoinitiator, a ketal type photoinitiator, a thioxanthone type photoinitiator, an acylphosphine oxide type photoinitiator, etc. are mentioned.

Examples of the benzoin ether-based photopolymerization initiator include benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, benzoin isopropyl ether, benzoin isobutyl ether, 2,2-dimethoxy-1,2- diphenylethan-1-one [manufactured by BASF, trade name: Irgacure 651], anisolemethyl ether, and the like, but are not limited thereto.

Examples of the acetophenone-based photopolymerization initiator include 1-hydroxycyclohexylphenylketone [manufactured by BASF, trade name: Irgacure 184], 4-phenoxydichloroacetophenone, 4-t-butyl-dichloroacetophenone, 1 -[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one [manufactured by BASF, trade name: Irgacure 2959], 2-hydroxy-2 -methyl-1-phenyl-propan-1-one [manufactured by BASF, trade name: Darocure-1173], methoxyacetophenone, and the like. Examples of the α-ketol-based photopolymerization initiator include 2-methyl-2-hydroxypropiophenone, 1-[4-(2-hydroxyethyl)-phenyl]-2-hydroxy-2-methylpropane- 1-one, and the like, but are not limited thereto.

Examples of the aromatic sulfonyl chloride-based photopolymerization initiator include, but are not limited to, 2-naphthalenesulfonyl chloride.

Examples of the photoactive oxime-based photopolymerization initiator include, but are not limited to, 1-phenyl-1,1-propanedione-2-(o-ethoxycarbonyl)-oxime.

The benzoin-based photopolymerization initiator includes, for example, benzoin, and the benzyl-based photopolymerization initiator includes, for example, benzyl, and the benzophenone-based photopolymerization initiator includes, for example, benzophenone and benzoyl. benzoic acid, 3,3'-dimethyl-4-methoxybenzophenone, polyvinyl benzophenone, α-hydroxycyclohexylphenyl ketone, and the like, but are not limited thereto.

The said ketal-type photoinitiator is, for example, benzyl dimethyl ketal, etc. are mentioned, The said thioxanthone-type photoinitiator is, for example, thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2 , 4-dimethyl thioxanthone, isopropyl thioxanthone, 2,4-dichloro thioxanthone, 2,4-diethyl thioxanthone, isopropyl thioxanthone, 2,4-diisopropyl thioxanthone, and dodecyl thioxanthone, but is not limited thereto.

Examples of the acylphosphine-based photopolymerization initiator include bis(2,6-dimethoxybenzoyl)phenyl phosphine oxide, bis(2,6-dimethoxybenzoyl)(2,4,4-trimethylpentyl)phosphine oxide, Bis(2,6-dimethoxybenzoyl)-n-butylphosphineoxide, bis(2,6-dimethoxybenzoyl)-(2-methylpropan-1-yl)phosphineoxide, bis(2,6-dimethy Toxybenzoyl)-(1-methylpropan-1-yl)phosphine oxide, bis(2,6-dimethoxybenzoyl)-t-butylphosphineoxide, bis(2,6-dimethoxybenzoyl)cyclohexyl phosphine oxide Cid, bis(2,6-dimethoxybenzoyl) octyl phosphineoxide, bis(2-methoxybenzoyl)(2-methylpropan-1-yl)phosphineoxide, bis(2-methoxybenzoyl)(1- Methylpropan-1-yl) phosphineoxide, bis(2,6-diethoxybenzoyl)(2-methylpropan-1-yl)phosphineoxide, bis(2,6-diethoxybenzoyl)(1-methylpropane -1-yl) phosphine oxide, bis (2,6-dibutoxybenzoyl) (2-methylpropan-1-yl) phosphine oxide, bis (2,4-dimethoxybenzoyl) (2-methylpropane-1 -yl) phosphine oxide, bis (2,4,6-trimethylbenzoyl) (2,4-dipentoxy phenyl) phosphine oxide, bis (2,6-dimethoxybenzoyl) benzyl phosphine oxide, bis (2, 6-dimethoxybenzoyl)-2-phenylpropyl phosphineoxide, bis(2,6-dimethoxybenzoyl)-2-phenylethyl phosphineoxide, bis(2,6-dimethoxybenzoyl)benzyl phosphineoxide, bis (2,6-dimethoxybenzoyl)-2-phenylpropyl phosphine oxide, bis(2,6-dimethoxybenzoyl)-2-phenylethyl phosphine oxide, 2,6-dimethoxybenzoylbenzylbutyl phosphine oxide, 2,6-dimethoxybenzoylbenzyloctyl phosphine oxide, bis(2,4,6-trimethylbenzoyl)-2,5-diisopropylphenyl phosphine oxide, bis(2,4,6-trimethylbenzoyl)-2 -Methylphenyl phosphineoxide, bis(2,4,6-trimethylbenzoyl)-4-methylphenyl phosphineoxide, bis(2,4,6-trimethylbenzoyl)-2,5-diethylphenyl phosphineoxide, bis( 2,4,6-trimethylbenzoyl)-2,3,5,6-tetramethylphenyl phosphineoxide, bis(2,4,6-trimethylbenzoyl)-2,4-di-n-butoxyphenyl phosphineoxide , 2,4,6-trimethylbenzoyl Diphenyl phosphineoxide, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentyl phosphineoxide, bis(2,4,6-trimethylbenzoyl)isobutyl phosphineoxide, 2,6- Dimethoxybenzoyl-2,4,6-trimethylbenzoyl-n-butyl phosphineoxide, bis(2,4,6-trimethylbenzoyl)phenyl phosphineoxide, bis(2,4,6-trimethylbenzoyl)-2, 4-dibutoxyphenyl phosphine oxide, 1,10-bis[bis(2,4,6-trimethylbenzoyl)phosphineoxide]decane, tri(2-methylbenzoyl)phosphine oxide, and the like, but are limited thereto. it's not going to be

The content of the photopolymerization initiator may be included in an amount of 0.01 to 3 parts by weight, specifically 0.5 to 2 parts by weight, based on 100 parts by weight of the total acrylic syrup included therewith. When the content of the photopolymerization initiator is included within the above range, the polymerization reaction can be sufficiently performed, and a decrease in the molecular weight of the resulting polymer can be suppressed, thereby securing the cohesive force of the formed pressure-sensitive adhesive layer.

additive

The additive may be used without particular limitation according to the purpose of the user within the range that can achieve the object of the present invention, and specifically, a crosslinking accelerator, a silane coupling agent, an anti-aging agent, a colorant (pigment, dye, etc.), a UV absorber, antioxidants, chain transfer agents, plasticizers, softeners, antistatic agents, solvents, etc., but are not limited thereto, and these may be used alone or in combination of two or more.

The thickness of the pressure-sensitive adhesive sheet of the present invention may be 50 to 300㎛, specifically 100 to 200㎛.

The pressure-sensitive adhesive sheet may have excellent durability and processability within the suggested thickness range, and may have excellent transparency of the pressure-sensitive adhesive sheet.

The pressure-sensitive adhesive sheet according to an embodiment of the present invention has a moisture permeability of 100 g/m ² day or more, an adhesive strength to soda glass of 25 N/25 mm or more, and a decrease rate of the adhesive strength when left for 120 hours under the conditions of 23° C. and 95 RH% When this amount is 50% or more, there is an advantage in that the cleaning power by water is excellent and the reuse of the adherend is easy.

< optical member >

Another aspect of the present invention is an optical member including the adhesive sheet described above.

The optical member has an advantage that can be reused by easily removing the pressure-sensitive adhesive composition when a problem occurs in the process due to excellent cleaning power by water by including the pressure-sensitive adhesive sheet of the present invention.

Specifically, the optical member may include, but is not limited to, a polarizing plate, a retardation plate, an optical film for a plasma display, a conductive film for a touch panel, a reflective sheet, and a luminance enhancing film, and other optical members are also applicable do.

<Image display device>

Another aspect of the present invention is an image display apparatus including the above-described optical member.

Since the image display device includes the above-described optical member, there is an advantage that the optical members can be reused when a problem occurs in the process.

The image display device is not particularly limited, and for example, a liquid crystal display device (LCD), a field emission display device (FED), a plasma display device (PDP), an organic electroluminescent device (OLED), and the like may be mentioned.

Hereinafter, preferred examples are presented to help the understanding of the present invention, but the following examples are only illustrative of the present invention, and it will be apparent to those skilled in the art that various changes and modifications are possible within the scope and spirit of the present invention. , it is natural that such variations and modifications fall within the scope of the appended claims. In the following Examples and Comparative Examples, "%" and "part" indicating the content are by weight unless otherwise specified.

manufacturing example : Preparation of acrylic syrup

manufacturing example One.

A monomer mixture consisting of 60% by weight of 2-ethylhexyl acrylate (2-EHA) monomer and 40% by weight of methacrylamide (MAA) monomer was placed in a 1L reactor in which nitrogen gas was refluxed and a cooling device was installed to facilitate temperature control. After the input, nitrogen gas was purged for 1 hour to remove oxygen, and then maintained at 110°C. After uniformly mixing the monomer mixture, when the total weight of the monomer mixture was 100 parts by weight, 0.5 parts by weight of 1-hydroxy-cyclohexyl-phenyl-ketone as a photoinitiator was added. After stirring, UV lamp (10mW) was irradiated to prepare an acrylic syrup having a conversion rate of 25%.

manufacturing example 2 to 4.

It was carried out in the same manner as in Preparation Example 1, but an acrylic syrup was prepared with the composition shown in Table 1 below.

The weight average molecular weight and molecular weight distribution of the acrylic syrup were measured using GPC under the following conditions. The measurement result was converted using standard polystyrene of Agilent system for preparation of the calibration curve.

<Weight average molecular weight measurement conditions>

Meter: Agilent GPC (Agilent 1200 series, USA)

Column: 2 PL Mixed B connections

Column temperature: 40°C

Eluent: tetrahydrofuran

Flow rate: 1.0 mL/min

Concentration: ~1mg/mL (100 μl injection)

division (meth)acrylate monomer (weight %) photoinitiator
(parts by weight) polymer
conversion rate
(%) weight average
Molecular Weight
(Unit: million) 2-EHA BA MAA NMAA 2-HEA Preparation Example 1 (A1) 60 - 40 - - 0.5 25 90 Preparation Example 2 (A2) 50 10 - 40 - 0.5 25 88 Production Example 3 (A3) - 60 30 - 10 0.5 26 71 Production Example 4 (A4) 60 - - - 40 0.5 27 65 2-EHA: 2-ethylhexyl acrylate
BA: butyl acrylate
MAA: methacrylamide
NMAA: N-methylolacrylamide
2-HEA: 2-hydroxyethyl acrylate
Photoinitiator: 1-hydroxy cyclohexylphenyl ketone

Example 1 to 4 and comparative example One.

A pressure-sensitive adhesive composition was prepared by mixing the contents of the acrylic syrup and the photoinitiator of Preparation Example in the composition shown in Table 2 below.

A preliminary coating film was formed by applying the pressure-sensitive adhesive composition prepared above to a thickness of 150 μm on a release film coated with a silicone release agent. An additional release film was bonded on the preliminary coating film and cured through a TL Lamp (UVV) to prepare an adhesive sheet having a thickness of 150 μm.

Experimental example 1: Evaluation of the rate of decrease in adhesive strength

After peeling the release film on one side of each adhesive sheet prepared in the Examples and Comparative Examples, corona-treating and bonding the 38 μm PET film and the adhesive side, cut the specimen so that the width is 25 mm and the length is 200 mm manufacture Next, the release film attached to the PET/adhesive layer configuration is peeled off, and the adhesive sheet is attached to the alkali-free tempered glass using a roller of 2 kg according to the regulations of JIS Z 0237, and then in an autoclave (50°C, 5 atmospheres). The pressure-sensitive adhesive sheet was removed from alkali-free tempered glass using an autograph (AG-1S, SHIMADZU) for a sample that was compressed for about 20 minutes and stored for 1 hour under constant temperature and humidity conditions (23° C., 50% RH). The initial peel force was measured while peeling 100 mm at a peeling rate of 0.3 m/min and a peeling angle of 180°.

In addition, after each of the adhesive sheets was left for 120 hours under the conditions of 23° C. and 95 RH%, the moisture-resistant peeling force was measured in the same manner as the initial peeling force, and the initial peeling force and the moisture-resistant peeling force were compared to reduce the adhesive strength. was calculated, and the results are shown in Table 2 below.

Experimental example 2: moisture permeability measurement

The release film on one side of each pressure-sensitive adhesive sheet prepared in the above Examples and Comparative Examples was peeled off, and after bonding to a 25 μm-thick triacetyl cellulose film (water vapor permeability: 1070 g/m 2 ·24 h), the release of the other side The film was peeled, and it measured in the temperature of 40 degreeC, and a humidity of 90%RH atmosphere based on the water vapor transmission rate test (cup method) of JISZ0208. In addition, the water vapor transmission rate obtained here is the water vapor transmission rate of the laminate of the triacetyl cellulose film and the pressure-sensitive adhesive sheet, but considering that the water vapor transmission rate of the triacetyl cellulose film is sufficiently larger than the water vapor transmission rate of the pressure-sensitive adhesive sheet, the water vapor transmission rate of the triacetyl cellulose film is calculated as that of the pressure-sensitive adhesive sheet. It was considered as the moisture permeability. The results are shown in Table 2 below.

Experimental example 3: detergency evaluation

Each of the pressure-sensitive adhesive sheets prepared in Examples and Comparative Examples were evaluated for cleaning in the following order.

i) bonding an adhesive sheet (15 mm × 15 mm) on at least one surface of a glass substrate and then exposing the adhesive sheet to a glass substrate by exposing the adhesive sheet to a glass substrate;

ii) the sample and sabina After fixing to a film friction tester (Linear Crockmeter), the step of wetting the cleaning solution to the sample and sabina; and

iii) Measuring the number of reciprocations when the pressure-sensitive adhesive layer on the sample is completely removed by reciprocating in different directions after bringing the sample and the surface soaked with the cleaning solution into contact with each other as the number of cleaning.

ⓞ : less than 50 times

○ : More than 50 times and less than 100 times

× : 100 times or more

Example comparative example One 2 3 One Acrylic syrup (parts by weight) Kinds A1 A2 A3 A4 content 100 100 100 100 photoinitiator
(parts by weight) ¹⁾ 0.5 0.5 0.5 0.5 adhesiveness Early 32 35 38 42 inroad 15 17 16 40 Adhesion decrease rate (%) 53 51 58 5 moisture permeability
(g/m²・24h) 231 226 188 273 Cleanliness (ash) ⓞ ○ ○ × 1)2,2-dimethoxy-1,2-diphenylethanone

Referring to Table 2, the pressure-sensitive adhesive sheets of Examples 1 to 3, which were prepared by using the pressure-sensitive adhesive composition containing the acrylic polymer according to the present invention, and satisfy moisture content and moisture permeability, were prepared using the pressure-sensitive adhesive composition containing the acrylic polymer according to the present invention. It was confirmed that the cleaning property was superior to that of the pressure-sensitive adhesive sheet of Comparative Example 1, which was prepared using the composition and did not satisfy the moisture content or the elastic modulus.

Claims (7)

The moisture permeability is 100g/m ² ㆍday or more,
Adhesion to soda glass is 25N/25mm or more,
A pressure-sensitive adhesive sheet, characterized in that the decrease in the adhesive strength is 50% or more when left for 120 hours under the conditions of 23 ℃, 95RH%,
The pressure-sensitive adhesive sheet includes a cured product of the pressure-sensitive adhesive composition,
The pressure-sensitive adhesive composition is a repeating unit derived from an acrylic monomer containing a _{C 1} to C _{20 linear, branched or alicyclic alkyl group;} and a repeating unit derived from an amide-based monomer; including an acrylic syrup containing a polymerized acrylic polymer,
With respect to 100% by weight of the total acrylic polymer, the repeating unit derived from the acrylic monomer is included in 80 to 90% by weight, and the repeating unit derived from the amide-based monomer is included in an amount of 10% by weight or more. delete delete delete According to claim 1,
The pressure-sensitive adhesive composition further comprises at least one selected from the group consisting of a photopolymerization initiator and additives. An optical member comprising the pressure-sensitive adhesive sheet according to any one of claims 1 to 5. An image display device comprising the optical member of claim 6 .