Pressure-sensitive adhesive composition

Abstract

A pressure-sensitive adhesive composition that improves not only durability but also bending characteristics of a polarizing plate, an optical laminate and a polarizing plate, both of which are prepared with said pressure-sensitive adhesive composition, and a display device comprising the optical laminate and the polarizing plate.

Claims

1. A pressure-sensitive adhesive composition containing a block copolymer, wherein the block copolymer comprises: a first block having a glass transition temperature of 50° C. or higher and a first cross-linkable functional group; and a second block having a glass transition temperature of −10° C. or lower and a second cross-linkable functional group and an aromatic group represented by Formula 2 below: ##STR00004## wherein, R.sub.1 is hydrogen or an alkyl group, R2 is an alkylene group or an alkylidene group, m is an integer of 0 to 5, X is a single bond, an oxygen atom or a sulfur atom, and Ar is an aryl group.

2. The pressure-sensitive adhesive composition according to claim 1, wherein each of said first and said second cross-linkable functional groups is independently a hydroxy group, a carboxyl group, an epoxy group, or an isocyanate group.

3. The pressure-sensitive adhesive composition according to claim 1, wherein said second block comprises a polymerized unit derived from 20 to 98 parts by weight of (meth)acrylic acid ester, a polymerized unit derived from 1 to 40 parts by weight of a compound capable of providing said second cross-linkable functional group, and a polymerized unit derived from 1 to 40 parts by weight of a compound capable of providing said aromatic group.

4. The pressure-sensitive adhesive composition according to claim 3, wherein said first block comprises a polymerized unit derived from 80 to 99 parts by weight of (meth)acrylic acid ester and a polymerized unit derived from 1 to 20 parts by weight of a compound capable of providing said first cross-linkable functional group.

5. The pressure-sensitive adhesive composition according to claim 4, wherein each of said first block and said second block has a polymerized unit derived from a compound of Formula 1 capable of providing said first and second cross-linkable functional groups: ##STR00005## wherein, Q is hydrogen or an alkyl group, A and B are each independently an alkylene group or an alkylidene group, and n is an integer in a range of 0 to 10.

6. The pressure-sensitive adhesive composition according to claim 1, wherein said second block comprises a polymerized unit derived from 1 to 35 parts by weight of said compound capable of providing an aromatic group.

7. The pressure-sensitive adhesive composition according to claim 1, wherein said second block comprises 50 parts by weight or less of alkyl (meth)acrylate having 1 to 3 carbon atoms.

8. The pressure-sensitive adhesive composition according to claim 1, wherein said first block has a number average molecular weight (Mn) in a range of 10,000 to 250,000.

9. The pressure-sensitive adhesive composition according to claim 8, wherein said first block has a molecular weight distribution in a range of 1.0 to 3.0.

10. The pressure-sensitive adhesive composition according to claim 1, wherein said block copolymer has a number average molecular weight (Mn) in a range of 100,000 to 500,000 and a molecular weight distribution in a range of 2.0 to 5.0.

11. The pressure-sensitive adhesive composition according to claim 1, wherein said block copolymer is a diblock copolymer or a triblock copolymer.

12. The pressure-sensitive adhesive composition according to claim 1, wherein said block copolymer is a diblock copolymer comprising 5 parts by weight to 50 parts by weight of said first block and 50 parts by weight to 95 parts by weight of said second block.

13. The pressure-sensitive adhesive composition according to claim 12, wherein said diblock copolymer comprises 10 parts by weight to 30 parts by weight of said first block and 70 to 90 parts by weight of said second block.

14. The pressure-sensitive adhesive composition according to claim 1, further comprising 0.01 to 20 parts by weight of a cross-linking agent relative to 100 parts by weight of said block copolymer.

15. The pressure-sensitive adhesive composition according to claim 1, further comprising 0.1 to 20 parts by weight of an antistatic agent relative to 100 parts by weight of said block copolymer.

16. A pressure-sensitive adhesive optical laminate comprising an optical film; and a pressure-sensitive adhesive layer formed on at least one side of said optical film and formed from the pressure-sensitive adhesive composition of claim 1.

17. A pressure-sensitive adhesive polarizing plate having a polarizing plate comprising a polarizer; and a pressure-sensitive adhesive layer positioned on at least one side of said polarizing plate and formed from the pressure-sensitive adhesive composition of claim 1.

18. A display device comprising a liquid crystal panel; and the pressure-sensitive adhesive optical laminate according to claim 16.

19. A display device comprising a liquid crystal panel; and the pressure-sensitive adhesive polarizing plate according to claim 17 positioned on at least one side of said liquid crystal panel.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) FIG. 1 is a schematic view for explaining a bending characteristic evaluation method in connection with experimental examples of the present application.

(2) FIG. 2 is a schematic view for explaining a light leakage evaluation method in connection with experimental examples of the present application.

BEST MODE

(3) Hereinafter, the present application will be described in detail through examples. However, the scope of protection of the present application is not limited by the examples described below.

(4) The physical properties in these examples and comparative examples were evaluated in the following manner.

(5) 1. Evaluation of Molecular Weight Characteristics

(6) The number average molecular weight (Mn) and the molecular weight distribution (PDI) of the block or block copolymer were measured using GPC (gel permeation chromatograph), and the GPC measurement conditions were as follows. The measurement results were converted using standard polystyrene (manufactured by Aglient system) for preparing the calibration curve.

(7) <GPC Measurement Conditions>

(8) Measuring instrument r: Aglient GPC (Aglient 1200 series, U.S.)

(9) Column: Two PL Mixed B connected

(10) Column temperature: 40° C.

(11) Eluent: THF (tetrahydrofuran)

(12) Flow rate: 1.0 mL/min

(13) Concentration: ˜1 mg/mL (100 μl injection)

(14) 2. Evaluation of Durability

(15) The polarizing plates prepared in Examples and Comparative Examples were each tailored to have a width of about 106 mm and a length of about 142 mm, and attached to a 7-inch commercial liquid crystal panel. Thereafter, the panel with the attached polarizing plate is stored for about 20 minutes in an autoclave (50° C., 5 atm) to prepare a sample. In the case of the moist-heat resistant durability of the prepared sample, it was evaluated according to the following criteria by observing occurrence of bubbles and peeling at the pressure-sensitive adhesive interface after leaving the sample to stand at 65° C. and 95% relative humidity for 500 hours. In the case of the heat resistant durability, it was evaluated according to the following criteria by also observing occurrence of bubbles and peeling after maintaining the sample at 100° C. for 500 hours.

(16) <Heat Resistant and Moist-Heat Resistant Durability Evaluation Criteria>

(17) A: no bubbles and peeling occurred

(18) B: slight bubbles and/or peeling occurred

(19) C: large amount of bubbles and/or peeling occurred

(20) 3. Glass Transition Temperature

(21) The glass transition temperature (Tg) of a block copolymer or each block of the block copolymer was calculated according to Equation A below.
1/Tg=ΣWn/Tn  <Equation A>

(22) In Equation above, Wn is a weight fraction of the monomer applied to a block copolymer or each block of the block copolymer, and Tn represents a glass transition temperature when each of the corresponding monomers has formed a homopolymer. That is, in Equation A, the right side is a result of summing up the calculated values after calculating all the values (Wn/Tn) obtained by dividing the weight fraction of the used monomer by the glass transition temperature appearing when the monomer has formed the homopolymer for each monomer.

(23) 4. Evaluation of Bending Characteristics

(24) The bending characteristics were evaluated using a strip measuring method (glass bending measurement). First, STN sodalime glass (4×41 cm.sup.2, 0.4 t) for bending is prepared. If there is no foreign material, it is used as such without washing, and if there are foreign materials, it is washed cleanly with EAc and IPA solvents and then dried using an air-gun. A polarizing plate (coated product) with the attached pressure-sensitive adhesive is prepared to a size of 3.5×40.5 cm.sup.2 in a long MD direction. A specimen is attached to the prepared bending glass using a laminator. After measuring the degree of bending (initial value) in the attached state, it is stored for 72 hours under heat resistant condition at 100° C. As shown in FIG. 1, after preparing a device capable of fixing a sample in a chamber, the sample is fixed on one side of the bending sample, and then the distance from the reference point is measured. At this time, the initial value was subtracted from the measured distance. Three samples were prepared for the same formulation and the average was calculated.

(25) 5. In-Plane-Retardation Measurement

(26) Pressure-sensitive adhesives formed from the pressure-sensitive adhesive compositions of Examples and Comparative Examples were each laminated on a primer-treated, non-stretched COP (cyclopolyolefin) film and tailored to a size of 1 cm wide and 5 cm long to prepare a specimen. The pressure-sensitive adhesive surface of this specimen is attached to a 0.7 t thick soda lime glass with a size of 1 cm×1 cm, and then fixed to a jig, and mounted so that the beam of the AXO SCAN equipment can be incident perpendicularly onto the pressure-sensitive adhesive surface. Thereafter, while the specimen is pulled to perform stress deformation on the pressure-sensitive adhesive surface, in-plane-retardation values are read according to the applied force and recorded. As the stress is applied, the optical compensation monomers may be oriented to achieve the optical compensation, where as the value of |R| is closer to 0 from the range of 4 or less due to this optical compensation, it means that the effect of the light leakage reduction in the endurance condition is more excellent.
|R|=|R.sub.0—R.sub.i|

(27) R.sub.0=in-plane-retardation value in a state where no stress is applied

(28) R.sub.i=in-plane-retardation value in a state where a stress of 15N is applied

(29) 6. Light Leakage Evaluation

(30) In order to investigate uniformity of light transmittance, it was observed using a backlight whether there was a light leakage portion in the dark room.

(31) Panel type: LCD module for TN

(32) Specimen: 2 polarizing plates to which the pressure-sensitive adhesive fitting LCD module size is attached

(33) Polarizing plate check: polarizing plate tailored in the 45 degree direction with respect to the stretching direction

(34) Wide view liquid crystal direction check of polarizing plate: The long side of the polarizing plate is held with both hands and shone vertically on the LCD monitor so that light is not transmitted, and then the long side of the polarizing plate is bent toward the body to check which light of the left and right leaks, where if the light leaking direction is to the right, the down right direction is the liquid crystal direction.

(35) (1) The LCD module is disassembled, the polarizing plate attached to the LCD cell is removed and the cell surface is wiped with EAc.

(36) (2) After checking the wide view liquid crystal coating direction of the polarizing plate, the polarizing plate is attached so that the liquid crystal direction faces away from the side tap, as shown in FIG. 2. Two upper and lower specimens are attached to both sides of the cell in the state that the polarized light is crossed, and the direction is aligned so that the top and bottom of the liquid crystal direction cross.

(37) (3) The cell is stored for 240 hours under aging conditions (moist-heat resistant condition: a temperature of 65° C. and 95% relative humidity, heat resistant condition: a temperature of 100° C.), and then left to stand at room temperature for 2 hours to observe the light leakage.

(38) Method of observing light leakage: it was evaluated according to the following criteria by observing the LCD module with the naked eye while driving it.

(39) <Evaluation Criteria>

(40) A: it is difficult to determine the light leakage with the naked eye.

(41) B: slight light leakage

(42) C: some light leakage

(43) D: large amount of light leakage

(44) 7. Evaluation of Peel Force

(45) The pressure-sensitive polarizing plates prepared in Examples or Comparative Examples were each tailored so as to have a width of 25 mm and a height of 100 mm to prepare specimens. Subsequently, the release PET film attached to the pressure-sensitive adhesive layer is peeled off and the pressure-sensitive polarizing plate is attached to glass (soda lime glass) using a roller of 2 kg in accordance with the provision of JIS Z 0237. The glass with the attached polarizing plate is squeezed in an autoclave (50° C., 5 atm) for about 20 minutes and stored under constant temperature and humidity conditions (23° C., 50% relative humidity) for 24 hours to prepare a sample. Thereafter, the peel force is measured while peeling the polarizing plate from the glass at a peel rate of 0.3 m/min and a peel angle of 180°, using a TA equipment (Texture Analyzer, manufactured by Stable Micro Systems, UK).

(46) 8. Evaluation of Interface Adhesive Force

(47) The polarizing plates prepared in Examples and Comparative Examples were tailored so as to have a width of 25 mm and a height of 100 mm to prepare specimens. Thereafter, the specimen is attached to a PET (poly(ethylene terephthalate)) film via the pressure-sensitive adhesive layer to prepare a laminate, and after maintaining the laminate at room temperature for 3 days, the laminate is attached to a glass substrate with a double-sided tape so that the PET film comes to the top, and then the interface adhesive force is evaluated by measuring the adhesive force between the polarizing plate and the PET film while peeling the PET film at room temperature at a peel rate of 10 mm/sec and a peel angle of 180°.

Preparation Examples of Copolymers

Preparation Example 1. Preparation of Diblock Copolymer (A1)

(48) 0.098 g of EBiB (ethyl 2-bromoisobutyrate), 160 g of methyl methacrylate (MMA), 30 g of butyl methacrylate (BMA) and 10 g of hydroxyethyl methacrylate (HEMA) were mixed in 370 g of ethyl acetate (EAc). The reactor containing the mixture was sealed, purged with nitrogen and stirred at about 25° C. for about 30 minutes, and dissolved oxygen was removed through bubbling. Thereafter, 0.0338 g of CuBr.sub.2, 0.0876 g of TPMA (tris(2-pyridylmethyl)amine) and 0.226 g of V-65 (2,2′-azobis(2,4-dimethyl valeronitrile)) were introduced to the mixture in which oxygen was removed and the mixture was immersed in a reaction tank at about 67° C. to initiate the reaction (polymerization of the first block). When the conversion of methyl methacrylate was about 70%, a mixture of 888 g of n-butyl acrylate (BA), 15 g of hydroxybutyl acrylate (HBA), 100 g of benzyl acrylate (BzA) and 411 g of ethyl acetate (EAc), which had been previously bubbled with nitrogen, was introduced thereto in the presence of nitrogen. Then, 0.0264 g of CuBr.sub.2, 0.0685 g of TPMA and 0.335 g of V-65 were added to the reactor, and a chain extension reaction was carried out (polymerization of the second block). If the conversion of the monomer (BA) reached 80% or more, the reaction mixture was exposed to oxygen and diluted with an appropriate solvent to terminate the reaction, thereby preparing the block copolymer (in the above process, V-65 was appropriately divided and introduced until the end of the reaction in consideration of its half-life).

Preparation Examples 2 to 6. Preparation of Block Copolymers (A2 to A3 and B1 to B3)

(49) Block copolymers were prepared in the same manner as in Preparation Example 1, except that the raw materials used in the polymerization of the first block and the second block were controlled as in Table 1 below.

(50) TABLE-US-00001 TABLE 1 Diblock copolymer preparation example 1 2 3 4 5 6 A1 A2 A3 B1 B2 B3 First MMA ratio 80 70 80 80 70 70 block BMA ratio 15 20 15 10 10 10 HEMA ratio 5 10 5 — 10 10 BzMA ratio — — — 10 10 10 Tg (° C.) 92 84 92 93 88 88 Mn (x10,000) 8.7 5.8 8.7 8.2 5.5 5.5 PDI 2.01 2.05 2.01 1.98 2.1 2.1 Second BzA ratio 10 20 10 — — — block BA ratio 88.5 78 78.5 98.5 100 98.5 HBA ratio 1.5 2 1.5 1.5 — 1.5 MA ratio — — 10 — — — Tg (° C.) −50 −44.8 −44.4 −54.4 −54 −54.4 Block Mn (x10,000) 21.8 20.5 21.1 20.9 20.6 20.3 co- PDI 3.0 3.3 3.1 3.1 3.2 3.2 polymer First block: 20:80 15:85 20:80 20:80 15:85 15:85 second block (weight ratio) Monomer ratio unit: part by weight MMA: methyl methacrylate (homopolymer Tg: about 110° C.) BMA: butyl methacrylate (homopolymer Tg: about 26° C.) HEMA: hydroxyethyl methacrylate (homopolymer Tg: about 57° C.) BzMA: benzyl methacrylate (homopolymer Tg: about 52° C.) BzA: benzyl acrylate (homopolymer Tg: about 6° C.) BA: n-butyl acrylate (homopolymer Tg: about −54° C.) HBA: 4-hydroxybutyl acrylate (homopolymer Tg: about −80° C.) MA: methyl acrylate (homopolymer Tg: about 10° C.) Mn: number average molecular weight PDI: molecular weight distribution Tg: glass transition temperature

Preparation Example 7: Preparation of Triblock Copolymer (B4)

(51) 1.409 g of EBiB (ethyl 2-bromoisobutyrate), 903 g of butyl acrylate (n-BA, n-butyl acrylate), 31 g of 4-hydroxybutyl acrylate (4-HBA), 103.8 g of benzyl acrylate (BzA) and 335 g of butyl acetate (BAc) were poured into a reactor, sealed, performed nitrogen purging and stirring at about 25° C. for about 30 minutes, and then dissolved oxygen was removed through bubbling. Thereafter, 0.1297 g of CuBr.sub.2, 0.3362 g of TPMA (tris(2-pyridylmethyl)amine) and 1.2984 g of V-65 (2,2′-azobis(2,4-dimethyl valeronitrile)) were introduced to the mixture in which oxygen was removed and the mixture was immersed in a reaction tank at about 67° C. to initiate the reaction (polymerization of the second block). When the conversion of methyl methacrylate was about 90%, a mixture of 509 g of methyl methacrylate (MMA), 57 g of styrene and 243 g of butyl acetate (BAc), which had been previously bubbled with nitrogen, was introduced thereto in the presence of nitrogen. Then, 0.5522 g of V-65 was added to the reactor, and a chain extension reaction was carried out (polymerization of the first block into both ends of the second block). If the conversion of the monomer (MMA) reached 80% or more, the reaction mixture was exposed to oxygen and diluted with an appropriate solvent to terminate the reaction, thereby preparing the triblock copolymer having a number average molecular weight (Mn) of 88,000 and a molecular weight distribution (Mw/Mn) of 2.71. Here, the weight ratio of the first block:the second block:the first block is about 15:70:15 (in the above process, V-65 was appropriately divided and introduced until the end of the reaction in consideration of its half-life).

Preparation Examples 8 to 10: Preparation of Block Copolymers (B5 to B7)

(52) A triblock copolymer (B5) was prepared in the same manner as in Preparation Example 7, except that the raw materials used in the polymerization of the first block and the second block were controlled as in Table 2 below. In the case of Table 3, triblock copolymers (B6 and B7) were prepared in the same manner as in Preparation Example 7, except that first, the first block was prepared and the second block was prepared at both ends.

(53) TABLE-US-00002 TABLE 2 Triblock copolymer preparation example 7 8 B4 B5 First block MMA ratio 90 80 HEMA ratio — 10 Sty ratio 10 10 Tg (° C.) 109 103 Second block BzA ratio 10 10 BA ratio 87 87 HBA 3 3 Tg (° C.) −50 −50 First block MMA ratio 90 80 HEMA ratio — 10 Sty ratio 10 10 Tg (° C.) 109 103 Block copolymer Mn (×10,000) 8.8 8.9 PDI 2.71 2.74 First block:second block:first 15:70:15 15:70:15 block (weight ratio) Monomer ratio unit: part by weight MMA: methyl methacrylate (homopolymer Tg: about 110° C.) HEMA: hydroxyethyl methacrylate (homopolymer Tg: about 57° C.) Sty: styrene (homopolymer Tg: about 100° C.) BzA: benzyl acrylate (homopolymer Tg: about 6° C.) BA: n-butyl acrylate (homopolymer Tg: about −54° C.) HBA: 4-hydroxybutyl acrylate (homopolymer Tg: about −80° C.) Mn: number average molecular weight PDI: molecular weight distribution Tg: glass transition temperature

(54) TABLE-US-00003 TABLE 3 Triblock copolymer preparation example 9 10 B6 B7 Second block BzA ratio 10 10 BA ratio 87 87 HBA 3 3 Tg (° C.) −50 −50 First block MMA ratio 100 90 HEMA ratio — — Sty ratio — 10 Tg (° C.) 110 109 Mn (×10,000) 5.3 5.2 PDI 1.50 1.53 Second block BzA ratio 10 10 BA ratio 87 87 HBA 3 3 Tg (° C.) −50 −50 Block Mn (×10,000) 25 25.1 copolymer PDI 2.73 2.72 Second block:first block:second 45:10:45 45:10:45 block (weight ratio) Monomer ratio unit: part by weight MMA: methyl methacrylate (homopolymer Tg: about 110° C.) HEMA: hydroxyethyl methacrylate (homopolymer Tg: about 57° C.) Sty: styrene (homopolymer Tg: about 100° C.) BzA: benzyl acrylate (homopolymer Tg: about 6° C.) BA: n-butyl acrylate (homopolymer Tg: about −54° C.) HBA: 4-hydroxybutyl acrylate (homopolymer Tg: about −80° C.) Mn: number average molecular weight PDI: molecular weight distribution Tg: glass transition temperature

Preparation Example 11. Preparation of Random Copolymer (B8)

(55) A monomer mixture comprised of 98.5 parts by weight of n-butylacrylate (BA) and 1.5 part by weight of hydroxybutyl acrylate was introduced into a 1 L reactor refluxed by nitrogen gas and equipped with a cooling device for easy temperature control. Thereafter, 150 parts by weight of ethyl acetate (EAc) was introduced thereto as a solvent. Nitrogen gas was purged for about 60 minutes to remove oxygen, and then 0.09 parts by weight of AIBN (azobisisobutyronitrile) as a reaction initiator was introduced thereto while maintaining the temperature at 60° C. and reacted for about 8 hours to prepare a random copolymer (B8). The prepared random copolymer (B8) had a weight average molecular weight of 400,000 and a molecular weight distribution of 5.0.

Preparation Example 12. Preparation of Random Copolymer (B9)

(56) A random copolymer (B9) was prepared in the same manner as in Preparation Example 11, except that a monomer mixture composed of 20.0 parts by weight of benzyl acrylate (BzA), 78.5 parts by weight of n-butyl acrylate (BA) and 1.5 parts by weight of hydroxybutyl acrylate (HBA) was introduced thereto. The random copolymer (B9) had a number average molecular weight of 320,000 and a molecular weight distribution of 5.1.

EXAMPLES AND COMPARATIVE EXAMPLES

Example 1

(57) Preparation of Coating Liquid (Pressure-Sensitive Adhesive Composition)

(58) 0.25 parts by weight of a TDI-based cross-linking agent (Coronate L, manufactured by Japan NPU), 0.01 parts by weight of DBTDL (dibutyltin dilaurate) and 0.2 parts by weight of a silane coupling agent (SCA), relative to 100 parts by weight of the block copolymer (A1) prepared in Preparation Example 1, were mixed and ethyl acetate as a solvent was blended and controlled so as to have a coating solid content of about 25 wt % to prepare a coating liquid (pressure-sensitive adhesive composition).

(59) Production of Pressure-Sensitive Adhesive Polarizing Plate

(60) The prepared coating solution was coated on the release-treated surface of a release PET (poly(ethylene terephthalate)) (MRF-38, manufactured by Mitsubishi) having a thickness of 38 m so as to have a thickness after drying of about 23 m, and maintained in an oven at 80° C. for about 3 minutes. After drying, the coating layer formed on the release PET was laminated on one side of a polarizing plate (laminated structure of COP/PVA/COP: COP=cyclopolyolefin, PVA=polyvinyl alcohol-based polarizing film) to produce a pressure-sensitive polarizing plate. The results of measuring physical properties are shown in Table 5.

Examples 2 to 3 and Comparative Examples 1 to 9

(61) A pressure-sensitive adhesive composition (coating liquid) and a pressure-sensitive adhesive polarizing plate were prepared in the same manner as in Example 1, except that upon preparing the pressure-sensitive adhesive composition (coating liquid), components and ratios were each adjusted as in Table 4 below.

(62) TABLE-US-00004 TABLE 4 Cross- Polymer linking SCA Con- agent con- Type tent content DBTDL tent Example 1 A1 100 0.25 0.01 0.2 2 A2 100 0.25 0.01 0.2 3 A3 100 0.25 0.01 0.2 Comparative 1 B1 100 0.25 0.01 0.2 Example 2 B2 100 0.25 0.01 0.2 3 B3 100 0.25 0.01 0.2 4 B4 100 0.25 0.01 0.2 5 B5 100 0.25 0.01 0.2 6 B6 100 0.25 0.01 0.2 7 B7 100 0.25 0.01 0.2 8 B8 100 0.25 0.01 0.2 9 B9 100 0.25 0.01 0.2 Content unit: part by weight Cross-linking agent: Coronate L, manufactured by Japan NPU DBTDL: dibutyltin dilaurate SCA: a silane coupling agent having a beta-cyanoacetyl group (M812, manufactured by LG Chem)

(63) TABLE-US-00005 TABLE 5 Light leakage Moist- Light (moist- heat leakage heat Heat resistant (heat resistant Interface Bending resistant durability resistant condition adhesive distance durability at 65° C., condition at 65° C., Peel force force (mm) at 100° C. 95% IΔRI at 100° C.) 95%) (gf/25 mm) (gf/25 mm) Example 1 16 A A 0.957 A A 380 3,450 2 17 A A 0.593 A A 450 3,320 3 18 A A 0.982 A A 420 3,210 Comparative 1 17 B B 3.034 C C 540 2,600 Example 2 2 C C 4.365 C C 2800* 780 3 20 B B 3.087 C C 520 3,130 4 16 C C 1.92 C C 42 1,160 5 17 C C 1.952 C C 40 1,450 6 18 C B 1.593 C C 150 1,880 7 19 C B 1.601 C C 100 1,850 8 20 C B 5.375 C C 350 1,260 9 21 C B 2.72 C C 330 1,100 *pressure-sensitive adhesive residue occurred on glass