KR101281952B1 - Adhesive composition for e-paper - Google Patents

Abstract

The present invention relates to an adhesive composition for electronic paper, and more specifically, by including an antistatic agent capable of dissociation, the surface resistance after curing is 10 ¹¹ Pa / sq or less, and the contrast ratio satisfies a condition of 5 or more, and is an electronic paper ITO film. The present invention relates to an adhesive composition for electronic paper, which exhibits excellent electrical driveability when attached thereto.

Description

Adhesive composition for electronic paper with excellent electric drive property {ADHESIVE COMPOSITION FOR E-PAPER}

The present invention relates to a pressure-sensitive adhesive composition for electronic paper, and more particularly, by including an antistatic agent capable of dissociation, has low electrical resistance of the pressure-sensitive adhesive composition, thereby excellent in electric driving performance, and accordingly, provides a contrast ratio of 5 or more required for an electronic paper panel. It is related with the adhesive composition for electronic paper which can be matched.

At present, research on an electronic paper device using an electrophoretic method, an electrochromic method, a thermal method, and a two-color particle rotation method as an image display device replacing liquid crystal has been actively conducted.

Such an electronic paper device is expected to be used in a next-generation image display device because a wide viewing angle closer to a normal printed matter is obtained than a liquid crystal, and power consumption is small and economical.

Among the above-mentioned electronic paper devices, in particular, the microcup type electronic paper device and the microcapsule type electronic paper device driven by the electrophoresis method, the adhesive composition should act as an electrical transfer between the ITO film, electrical resistance characteristics of the adhesive composition There was a need to lower.

An object of the present invention is to include an antistatic agent, thereby satisfying the condition that the surface resistance of the pressure-sensitive adhesive showing the electrical resistance after curing is 10 ¹¹ Ω / sq or less, thereby increasing the electrical response speed, and satisfies the condition of contrast ratio 5 or more, It is to provide a pressure-sensitive adhesive composition for electronic paper, which exhibits excellent electrical driveability when attached to an ITO film of electronic paper.

Adhesive composition for electronic paper according to an embodiment of the present invention for achieving the above object is characterized by satisfying the conditions of the following general formula (1).

[Formula 1]

X = 10 ¹¹ μs / sq or less and Y = 5 or more

(In the general formula 1, X represents the surface resistance to the cured product of the adhesive composition for electronic paper. Y is the contrast ratio and the white reflectance divided by the black reflectance.)

The adhesive composition for electronic paper according to the present invention has an advantage that it can be applied in a simple manner to form on the back of the transparent film and adhere to the microcups.

In addition, since the adhesive composition for electronic paper of the present invention contains an antistatic agent, the ion concentration in the composition is high and the electrical resistance is low. Therefore, the electrical response speed is excellent when used between ITO films. It is effective.

1 is a schematic diagram showing an adhesive film to which the adhesive composition for electronic paper according to an embodiment of the present invention is applied.

Advantages and features of the present invention and methods for achieving them will be apparent with reference to the embodiments described below in detail with the accompanying drawings. It should be understood, however, that the invention is not limited to the disclosed embodiments, but is capable of many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, To fully disclose the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

Hereinafter, an adhesive composition for an electronic paper according to the present invention will be described in detail with reference to the accompanying drawings.

1 illustrates an adhesive film to which an adhesive composition for electronic paper according to an embodiment of the present invention is applied. First, the adhesive composition for electronic paper of the present invention will be described.

Adhesive composition for electronic paper

Adhesive composition for electronic paper according to an embodiment of the present invention for achieving the above object is characterized by satisfying the conditions of the following general formula (1).

[Formula 1]

X = 10 ¹¹ μs / sq or less and Y = 5 or more

(In the general formula 1, X represents the surface resistance to the cured product of the adhesive composition for electronic paper. Y is the contrast ratio and the white reflectance divided by the black reflectance.)

To this end, the adhesive composition of the present invention may include (a) a base resin, (b) an antistatic agent, and (c) a curing agent.

The base resin (a) contained in the pressure-sensitive adhesive composition of the present invention is a resin having adhesiveness, and there is no particular limitation as long as it is a solution type pressure-sensitive adhesive resin. In particular, it is preferable that it is at least 1 type selected from silicone type, acryl type, urethane type, and rubber type. Among these, it is preferable to use acrylic copolymer resin.

Silicone-based is expensive and not easy to change the composition, urethane-based is difficult to satisfy the durability due to lack of adhesion, rubber-based is very limited and lacks long-term heat resistance.

Therefore, it is preferable to use an acrylic system which is easy to change the composition and has excellent durability and low cost. In particular, in order to prepare a very thin pressure-sensitive adhesive as in the present invention, it is preferable to use a solution type polymerization that is the easiest to control the viscosity rather than a bulk polymerization method or photopolymerization.

Here, although the composition of acrylic copolymer resin is not specifically limited, For example, 50-99 weight part of (meth) acrylic acid ester monomers and 1-50 weight part of crosslinkable functional group containing monomer with respect to 100 weight part of acrylic copolymer resins. It includes.

Here, the type of the (meth) acrylic acid ester monomer is not particularly limited, but if the alkyl group included in the monomer is too long, cohesion of the pressure-sensitive adhesive film is lowered, and glass transition temperature (Tg) and adhesion are difficult to control. Since there is a concern, it is preferable to use a (meth) acrylic acid ester monomer having an alkyl group having 1 to 12 carbon atoms.

Such monomers include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, t-butyl (meth) ) Acrylate, sec-butyl (meth) acrylate, pentyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, 2-ethylbutyl (meth) acrylate, n-octyl (meth) acrylate, iso Or may be used selected from the group consisting of octyl (meth) acrylate, isononyl (meth) acrylate, isobornyl (meth) acrylate, lauryl (meth) acrylate, and tetradecyl (meth) acrylate One kind or a mixture of two or more kinds can be used.

As described above, the (meth) acrylic acid ester monomer is preferably included in an amount of 50 to 99 parts by weight based on 100 parts by weight of the acrylic copolymer resin. When the content is less than 50 parts by weight, the initial adhesive strength of the pressure-sensitive adhesive is There exists a possibility that it may fall, and when it exceeds 99 weight part, there exists a possibility that a problem may arise in durability due to a fall of cohesion force.

The kind of crosslinkable functional group-containing monomer that can be used in the present invention is not particularly limited, but one or more kinds of carboxyl group-containing monomer, hydroxy group-containing monomer or nitrogen-containing monomer can be used.

In particular, the pressure-sensitive adhesive of the present invention is in direct contact with the indium tin oxide layer in the electronic paper panel configuration, so under the precondition that a composition which does not corrode the indium tin oxide layer should be used, it is not necessary to use a carboxyl functional monomer or use a small amount. desirable.

Examples of the carboxyl group-containing monomers include (meth) acrylic acid, 2- (meth) acryloyloxy acetic acid, 3- (meth) acryloyloxy propyl acid, 4- (meth) acryloyloxy butyl acid, and acrylic acid duplexes. , Itaconic acid, fumaric acid, maleic acid and maleic anhydride, the hydroxy group containing monomers are for example 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth ) Acrylate, 6-hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl (meth) acrylate, 2-hydroxyethylene glycol (meth) acrylate or 2-hydroxypropylene glycol (meth) acrylateyl The nitrogen-containing monomer can be, for example, (meth) acrylamide, N-vinyl pyrrolidone or N-vinyl caprolactam, but is not limited to the compositions described in the description.

The crosslinkable functional group-containing monomer included in the acrylic copolymer resin imparts cohesion and adhesive strength to the pressure-sensitive adhesive film, and serves to improve durability in high temperature and / or high humidity conditions.

Herein, the crosslinkable functional group-containing monomer is contained in an amount of 1 to 50 parts by weight based on 100 parts by weight of the acrylic copolymer resin, but if the content is less than 1 part by weight, agglomeration fracture occurs under high temperature and / or high humidity conditions. There is a fear that the reliability is lowered, and if it exceeds 50 parts by weight, the functional group content becomes too large, and the viscosity increases very much due to the interaction of the functional period, making it difficult to remove bubbles during coating, and also due to the decrease in compatibility, such as white turbidity. Phase separation problems may occur and may be difficult to use as an optical adhesive.

In particular, in the case of using a carboxyl monomer, the content thereof is used in an amount of 1 part by weight or more and 5 parts by weight or less based on 100 parts by weight of the polymer resin. If it is less than 1 part by weight, it is preferable to use another crosslinkable monomer. If it is used more than 5 parts by weight, corrosion of the indium tin oxide layer occurs, so it is preferable to use within the above range.

Although the monomer composition comprised as mentioned above is superposed | polymerized by a general solution polymerization process, the weight average molecular weight of said (a) solution type adhesive resin is although it does not specifically limit, It is preferable that it is 100,000-2 million. If the weight average molecular weight of the solution-type pressure-sensitive adhesive resin is less than 100,000, the cohesive strength of the pressure-sensitive adhesive may be lowered, durability reliability may be a problem, and if it exceeds 2 million, the wettability to the adherend deteriorates due to a decrease in the adhesive properties, the external There may be a problem such as lifting or bubble inflow caused by environmental changes.

The solution-type pressure-sensitive adhesive resin is cured to exhibit a transparent property, has an oxidation resistance, and may not be used in the pressure-sensitive adhesive composition for electronic paper of the present invention because yellowing does not occur due to light.

The antistatic agent (b) used in the present invention is excellent in compatibility with the pressure-sensitive adhesive, does not affect the transparency and durability, and may be any antistatic agent that provides electrical properties through dissociation of ions.

The antistatic agent is preferably used from 0.01 to 20 parts by weight based on 100 parts by weight of the acrylic copolymer. If the content is less than 0.01 parts by weight, there is a lack of a property of lowering the electrical resistance, if it exceeds 20 parts by weight there is a problem that the durability of the pressure-sensitive adhesive is weak due to the decrease in cohesion.

Specifically, the antistatic agent is a) an inorganic salt consisting of a metal cation and an anion; b) an organic salt consisting of an onium cation and an anion; c) a mixture of the inorganic salt and a chelating agent capable of forming a bond with a metal ion of the inorganic salt, and d) a mixture of the inorganic salt and a compound having at least one ether bond in the molecule. .

The anions of the inorganic salts or organic salts are iodide, chloride, bromide, nitrate, sulfonate, methylbenzenesulfonate, carboxybenzenesulfonate, benzoate, perchlorate, hydroxide, trifluoroacetate, trifluoromethane Sulfonate, tetrafluoroborate, tetrabenzylborate, hexafluorophosphate, bistrifluoromethanesulfonylimide, bispentafluoroethanesulfonylimide, bispentafluoroethanecarbonylimide, bisperfluoro It is preferably selected from the group consisting of robutanesulfonylimide, bisfluorobutanecarbonylimide, tristrifluoromethanesulfonylmethide, and tristrifluoromethanecarbonylmethide, but is not limited thereto. Imide-based anions are more preferable because fluorine is substituted with fluorine having a good double electron acceptor role and good hydrophobicity.

In addition, the metal cation includes an alkali metal or alkaline earth metal cation. Preferably the metal cation is selected from the group consisting of lithium, sodium, potassium, rubidium, cesium, beryllium, magnesium, calcium, strontium, and barium, more preferably lithium, sodium, potassium, cesium, beryllium, magnesium, Calcium, and barium. Most preferably, lithium having high ion stability and easy movement in the pressure-sensitive adhesive is used.

In addition, it is preferable to use nitrogen onium cation, phosphorus onium cation, or sulfur onium cation as an onium cation. Onium herein means ions that are positively charged in an amount that retains at least some of the charge localized on one or more nitrogen, phosphorus, or sulfur atoms.

The onium cation may be cyclic or acyclic in which the atom (s) are cyclic. The cyclic cation may be an aromatic saturated or unsaturated cation. Cyclic cations may contain one or more ring heteroatoms (eg, oxygen, sulfur) other than nitrogen, phosphorus, sulfur and may be optionally substituted by substituents such as hydrogen, halogen, alkyl, or aryl. Acyclic cations may have one or more (preferably four or more) organic substituents or R groups bound to nitrogen, with the remaining substituents being hydrogen. The R group may be cyclic or acyclic, substituted or unsubstituted, aromatic or non-aromatic, and may contain one or more hetero atoms (eg nitrogen, oxygen, sulfur, phosphorus, or halogen).

In particular, the nitrogen onium cation is preferably at least one selected from the group consisting of acyclic quaternary ammonium salts and aromatic ammonium salts. For example, the aromatic ammonium salt can be selected from pyridinium, pyridazinium, pyrimidinium, pyrazinium, imidazolium, pizzazonium, thiazolium, oxazolium and triazium.

More specifically, the preferred nitrogen onium cation is at least one compound selected from the group consisting of tetraalkylammonium, methyltributylammonium, 1,3-alkylmethylimidazolium and 1,2-dimethyl-3-alkylimidazolium.

On the other hand, when an inorganic salt consisting of a metal cation and an anion is used as an antistatic agent, at least one ether bond of the inorganic salt and the molecule or a mixture of the chelating agent capable of forming a bond with the metal salt of the inorganic salt and the inorganic salt is used. Preference is given to using mixtures of the compounds having.

The chelating agent usable in the present invention is a compound having a functional group capable of forming a bond with a metal ion in its molecular structure, and the chelating agent combines with a cation of a metal salt dissociated into a cation and an anion to form a stabilized chelate complex. Therefore, the anion concentration of the metal salt is increased in the pressure-sensitive adhesive, thereby having ion conductivity in the pressure-sensitive adhesive composition, and the ion conductivity imparts conductivity to the pressure-sensitive adhesive composition, thereby lowering the electrical resistance, resulting in lower surface resistance. Specifically, the chelating agent may be used alone or in combination of two or more kinds of compounds having an oxalate group, a diamine group, a polyvalent carboxyl group, a beta-ketone group, an oxime group, and the like, in particular a compound having an oxalate group is used. It is desirable to.

The chelating agent capable of forming a bond with the metal ion as described above is preferably included in an amount of 0.1 to 10 parts by weight based on 1 part by weight of the inorganic salt. If the content is less than 0.1 parts by weight, the inorganic resistance is not sufficiently combined with the high electrical resistance characteristics, if it exceeds 10 parts by weight there is a problem that the durability reliability is lowered due to the decrease in cohesion.

The curing agent (c) of the present invention is for adjusting the initial adhesive strength and cohesive force of the adhesive composition of the present invention, and specific examples thereof may include an isocyanate compound, an epoxy compound, an aziridine compound, or a metal chelate compound.

As said isocyanate compound, an aromatic polyvalent isocyanate compound, an aliphatic polyvalent isocyanate compound, an alicyclic polyvalent isocyanate compound, etc. are mentioned.

More specific examples of the organic polyvalent isocyanate compound include, for example, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, diphenylmethane- 4,4'-diisocyanate, diphenylmethane-2,4'-diisocyanate, 3-methyldiphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-di Isocyanate, dicyclohexyl methane-2,4'- diisocyanate, and lysine isocyanate.

Moreover, the trimer of these polyvalent isocyanate compounds, the terminal isocyanate urethane prepolymer obtained by making these polyvalent isocyanate compounds, and a polyol compound react etc. are contained in the said organic polyvalent isocyanate compound.

The epoxy compound may be ethylene glycol diglycidyl ether, triglycidyl ether, trimethylolpropane triglycidyl ether, N, N, N ', N'-tetraglycidyl ethylenediamine, or glycerin diglycidyl ether. Etc. can be used.

Meanwhile, the aziridine-based compound may be N, N'-toluene-2,4-bis (1-aziridinecarboxide), N, N'-diphenylmethane-4,4'-bis (1-aziridinecarboxa) Id), triethylenemelamine, tri-1-aziridinylphosphine oxide, or the like can be used.

The metal chelate compound may be a compound in which a polyvalent metal such as aluminum, iron, zinc, tin, titanium, antimony, magnesium, or vanadium is coordinated with acetylacetone or ethyl acetoacetate.

The curing agent as described above may be uniform coating processing work should be rarely occurring functional group crosslinking reaction of the curing agent in the compounding process for the formation of the adhesive layer. When the coating process is finished and the drying and aging process is completed, a crosslinked structure is formed to obtain an adhesive layer having strong elasticity and cohesive force. At this time, the adhesive property such as durability of the adhesive product is improved by the strong cohesive force of the adhesive.

It is preferable that 0.01-10 weight part of said hardening | curing agent is contained in 100 weight part of base resins of this invention, and it is more preferable that 0.1-5 weight part is included.

If the content of the curing agent is less than 0.01 parts by weight, the cohesive force is weak, there is a problem of durability, and if it exceeds 10 parts by weight, the pressure-sensitive adhesive is too hard, there is a problem that the adhesive performance is lowered.

Meanwhile, in the present invention, additives such as photoinitiators, silane binders, inorganic binders, brighteners, wetting properties, pigments, deodorants, antifoaming agents, antioxidants, organic flame retardants, thickeners, plasticizers, etc., are not lost inherent in electronic paper pressure-sensitive adhesive compositions. It is possible to use

Adhesive film for electronic paper

The present invention includes an adhesive film formed with a coating layer comprising the adhesive composition for electronic paper described above.

As illustrated in FIG. 1, the adhesive film of the present invention includes a coating layer 100 and a release film 200 including an adhesive composition for electronic paper.

First, the coating layer 100 containing the adhesive composition for electronic paper is characterized in that it satisfies the conditions of the following general formula (1).

[Formula 1]

X = 10 ¹¹ μs / sq or less and Y = 5 or more

(In the general formula 1, X represents the surface resistance to the cured product of the adhesive composition for electronic paper. Y is the contrast ratio and the white reflectance divided by the black reflectance.)

To this end, the coating layer 100 including the pressure-sensitive adhesive composition of the present invention may include (a) a base resin, (b) an antistatic agent, and (c) a curing agent, as described above. Will be omitted.

Meanwhile, the coating layer 100 including the adhesive composition for electronic paper may be formed on the release film 200. When the release film 200 peels off the coating layer 100 including the adhesive composition for electronic paper of the present invention, there is no limitation as long as peeling is easy so that there is no residual adhesive.

As the release film 200, for example, it is possible to use polyethylene terephthalate coated with a silicone release agent, or polyethylene terephthalate coated with a fluorine release agent depending on the wettability of the coating layer 100 including the adhesive composition of the present invention. Do.

On the other hand, when the coating layer 100 including the pressure-sensitive adhesive composition of the present invention is dried by hot air, the release film should not be deformed by heat, so that a polyimide coated with a release agent, polynaphthalene terephthalate, or the like is used depending on the drying temperature. It is also possible.

Example  And Comparative example

In order to determine the electrical resistance characteristics and contrast ratio according to the addition of the antistatic agent of the adhesive composition for electronic paper of the present invention, the adhesive composition for electronic paper was prepared through the following examples and comparative examples, and physical properties were evaluated accordingly.

Preparation of Acrylic Copolymer A

In a 1-liter reactor equipped with a refrigeration system for reflux of nitrogen gas and easy temperature control, 200 g of a monomer in a ratio of 60 parts by weight of ethylhexyl acrylate, 20 parts by weight of isobornyl acrylate, and 20 parts by weight of hydroxyethyl acrylate is used as a solvent. Into 500 g of ethyl acetate. After purging nitrogen gas for 1 hour to remove oxygen, 0.01 parts by weight of azobisisobutyronitrile (AIBN) thermal initiator was added and the reaction was carried out at a temperature of 60 ° C for 8 hours to polymerize an adhesive resin having a molecular weight of 600,000. It was.

Preparation of Acrylic Copolymer B

60 parts by weight of ethylhexyl acrylate, 20 parts by weight of isobornyl acrylate, 16 parts by weight of hydroxyethyl acrylate, and 4 parts by weight of acrylic acid in a 1 liter reactor equipped with a refrigeration system for reflux of nitrogen gas and for easy temperature control. 200 g of the monomer was added to 500 g of ethyl acetate as a solvent. After purging nitrogen gas for 1 hour to remove oxygen, 0.01 parts by weight of azobisisobutyronitrile (AIBN) thermal initiator was added and the reaction was carried out at a temperature of 60 ° C for 8 hours to polymerize an adhesive resin having a molecular weight of 700,000. It was.

Manufacture adhesive film for electronic paper

After coating the composition mixed with the antistatic agent and the curing agent in a composition as shown in Table 1 with respect to 100 parts by weight of the acrylic copolymer prepared above on a 50μm release PET film and dried at 110 degrees for 3 minutes, an adhesive film having a thickness of 10μm Prepared.

Adhesive resin Antistatic agent Hardener Example 1 Preparation Example A
100 parts by weight
(Mw = 600,000) Lithium Bis (trifluoromethanesulfonyl) imide (LiTFSI)
0.1 parts by weight Isophorone diisocyanate
1.0 parts by weight Example 2 Preparation Example A
100 parts by weight
(Mw = 600,000) Lithium Bis (trifluoromethanesulfonyl) imide (LiTFSI)
1.0 parts by weight Isophorone diisocyanate
1.0 parts by weight Example 3 Preparation Example A
100 parts by weight
(Mw = 600,000) 10 parts by weight of methyltributylammonium bistrifluoromethanesulfonylimide Hexamethylene diisocyanate
1.0 parts by weight Example 4 Preparation Example B
100 parts by weight
(Mw = 700,000) Lithium Perchlorate
(LiClO ₄ )
1.0 parts by weight Isophorone diisocyanate
1.0 parts by weight
N, N'-diphenylmethane-4,4'-bis (1-aziridinecarboxide)
0.3 parts by weight Example 5 Preparation Example B
100 parts by weight
(Mw = 700,000) Lithium hexafluorophosphate (LiPF ₆ )
5 parts by weight N, N'-diphenylmethane-4,4'-bis (1-aziridinecarboxide)
0.5 parts by weight Example 6 Preparation Example B
100 parts by weight
(Mw = 700,000) Lithium Perchlorate
(LiClO ₄ )
1.0 parts by weight
Lithium Bis (trifluoromethanesulfonyl) imide (LiTFSI)
3.0 parts by weight Triethylenemelamine
2.0 parts by weight Comparative Example 1 Preparation Example A
100 parts by weight
(Mw = 600,000) - Isophorone diisocyanate
1.0 parts by weight Comparative Example 2 Preparation Example A
100 parts by weight
(Mw = 600,000) Lithium Bis (trifluoromethanesulfonyl) imide (LiTFSI)
0.005 parts by weight Isophorone diisocyanate
1.0 parts by weight Comparative Example 3 Preparation Example B
100 parts by weight
(Mw = 700,000) Lithium Bis (trifluoromethanesulfonyl) imide (LiTFSI)
30 parts by weight Isophorone diisocyanate
1.0 parts by weight

evaluation

1. Surface resistance measurement

The surface resistance of the coating layer formed by aging the composition of Table 1 after hot air drying was measured and shown in Table 2 below. In the measurement of surface resistance, after the adhesive composition was coated, the release film, which was covered on the upper and lower portions, was removed, and the surface resistance of the adhesive surface was measured. Specifically, a voltage of 500 V under 23 ° C. and 55% RH was measured. After application for minutes, the surface resistance value was used as the surface resistance value of the present invention.

2. Contrast Ratio Measurement

In addition, after using the electronic paper sealing material consisting of the composition of Table 1 to produce a simple panel for electronic paper, contrast ratio using a spectrophotometer (i1 Basic Pro, X-RITE) under 23 ℃ and 55% RH environment Measured and shown in Table 2 below. White reflectance and black reflectance were measured and the ratio was used as the contrast ratio value. The larger this value is, the more it can be determined that a clear image is realized, and furthermore, the faster the response can be estimated.

Surface resistance (Ω / sq) Contrast ratio Example 1 1.0 ⅹ 10 ¹¹ 5.2 Example 2 1.1 ⅹ 10 ⁹ 6.1 Example 3 6.7 ⅹ 10 ⁸ 7.0 Example 4 5.8 ⅹ 10 ⁹ 6.5 Example 5 9.2 ⅹ 10 ⁸ 7.2 Example 6 3.5 ⅹ 10 ¹⁰ 5.8 Comparative Example 1 More than 10 ¹⁴ 2.4 Comparative Example 2 7.5 ⅹ 10 ¹³ 3.1 Comparative Example 3 2.2 ⅹ 10 ⁷ Not measurable

As shown in Table 2, in the case of the pressure-sensitive adhesive layer composition of the present invention, it was found that the surface resistance is excellent by including an antistatic agent, and thus, the contrast ratio is also excellent.

However, when the antistatic agent is added beyond the range suggested in the present invention, the surface resistance is low and the electrical resistance characteristics are excellent. Therefore, the contrast ratio is expected to be excellent. The panel state was poor and the contrast ratio could not be measured.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. . Accordingly, the true scope of the present invention should be determined by the following claims.

100: coating layer
200: release film

Claims (8)

Adhesive composition for electronic paper which satisfies the conditions of the following general formula (1).

[Formula 1]
X = 10 ¹¹ μs / sq or less and Y = 5 or more
(In the general formula 1, X represents the surface resistance to the cured product of the adhesive composition for electronic paper. Y is the contrast ratio and the white reflectance divided by the black reflectance.)
The method of claim 1,
The pressure-sensitive adhesive composition is a pressure-sensitive adhesive composition for electronic paper, characterized in that (a) a base resin, (b) an antistatic agent, (c) a curing agent.
The method of claim 2,
The (a) base resin is an adhesive composition for electronic paper, characterized in that the solution-type adhesive resin.
The method of claim 2,
(B) the antistatic agent is a) an inorganic salt consisting of a metal cation and an anion; b) an organic salt consisting of an onium cation and an anion; c) a mixture of the inorganic salt and a chelating agent capable of forming a bond with the metal ion of the inorganic salt, and d) a mixture of the inorganic salt and a compound having at least one ether bond in the molecule. Adhesive composition for electronic paper.
The method of claim 2,
The antistatic agent (b) is an adhesive composition for electronic paper, characterized in that 0.01 to 20 parts by weight based on 100 parts by weight of the base resin.
The method of claim 2,
Wherein (c) the curing agent is an adhesive composition for electronic paper, characterized in that at least one selected from isocyanate compound, epoxy compound, aziridine compound, metal chelate compound.
The method of claim 2,
Wherein (c) the curing agent is 0.01 to 10 parts by weight based on 100 parts by weight of the base resin, the adhesive composition for electronic paper.
The adhesive film for electronic paper with a coating layer containing the adhesive composition for electronic paper of any one of Claims 1-7.

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