KR20160004928A

KR20160004928A - Adhesive for optical film, adhesive layer, adhesive optical film, and dispaly device

Info

Publication number: KR20160004928A
Application number: KR1020150092561A
Authority: KR
Inventors: 타츠히로 스와; 히로시 오가와
Original assignee: 삼성에스디아이 주식회사
Priority date: 2014-07-03
Filing date: 2015-06-29
Publication date: 2016-01-13
Also published as: TWI588231B; TW201631104A; JP2016014827A; KR101933262B1; JP6630728B2; JP2017528581A; CN106661402A; CN106661402B

Abstract

The present invention relates to an adhesive composition for an optical film, an adhesive layer, an adhesive-type optical film, and a display device. The adhesive composition for an optical film of the present invention can have both reworkability and reliability by including an adhesive resin having an acid value of 0 to 20 mgKOH/g and a silicate oligomer represented by chemical formula 1. In the chemical formula 1, R_1 to R_4 are respectively hydrogen, an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms; X_1 and X_2 are respectively are hydrogen, an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon number; and n is an integer of 1 to 100.

Description

TECHNICAL FIELD [0001] The present invention relates to a pressure-sensitive adhesive composition for an optical film, a pressure-sensitive adhesive layer, a pressure-sensitive adhesive optical film,

The present invention relates to a pressure-sensitive adhesive composition for an optical film, a pressure-sensitive adhesive layer, a pressure-sensitive optical film and a display device containing the same.

The display device includes a display element such as a liquid crystal cell. Such a display element may be attached to various films according to a desired function and purpose. For example, the liquid crystal cell includes polarizing films on both sides in accordance with a specific image forming method. In addition to the polarizing film, the liquid crystal cell may further include a retardation plate, a viewing angle enlarging film, a luminance improving film, various protective films, and the like in order to improve the image quality. Hereinafter, the film to be attached to the display element is collectively referred to as an optical film.

In general, the display element may comprise one or more optical films. For example, the optical film may be directly attached to the display element, or a plurality of optical films may be laminated on the display element. In this case, the optical film may be attached to the display element or another optical film using a pressure-sensitive adhesive.

At this time, the optical film is often used in the form of an adhesive optical film having an adhesive layer formed on at least one surface. When a pressure-sensitive adhesive optical film is used, there is an advantage that the step of drying the pressure-sensitive adhesive can be omitted.

However, when the adhesive optical film is pasted on a display element, there may be an error in the bonding position or foreign matter may enter the bonding face. In this case, the optical element is peeled from the display element to reuse the display element. Therefore, the pressure-sensitive adhesive for an optical film is required to be re-peelable (reworkability). Specifically, the reworkability means that the adhesive layer formed of the adhesive for an optical film does not break the display element at the time of peeling, and does not leave a residual adhesive or the like on the display element at the time of peeling.

In order to improve the reworkability of the adhesive layer, the adhesive strength of the adhesive for optical films should be lowered. Such reworkability is more important in thinned optical films and display devices as in recent trends. For example, when the thickness of the optical film and the display element is reduced due to thinning, the breaking strength of the optical film and the display element is reduced. Therefore, the adhesive used for the thin optical film and the display element needs to further lower the adhesive force to prevent breakage.

On the other hand, reliability (durability) capable of stably bonding an optical film, an optical film or an optical film and a display element to a pressure-sensitive adhesive is also required. However, in order to secure the reworkability of the pressure-sensitive adhesive layer, if the adhesive force of the pressure-sensitive adhesive is largely decreased, the reliability of the pressure-sensitive adhesive layer may be greatly impaired. As described above, there is a problem that it is very difficult to achieve both reworkability and reliability of the pressure-sensitive adhesive for an optical film. Such a problem has not been particularly easy to solve when the optical film and the display element are thin.

Patent Documents 1 to 4 disclose a technique relating to a pressure-sensitive adhesive. However, the techniques disclosed in Patent Documents 1 to 4 can not solve the above-described problems.

Patent Document 1 proposes a pressure-sensitive adhesive composition for an optical film, which comprises a (meth) acrylic polymer and a polyether having a reactive silyl group. However, the pressure-sensitive adhesive disclosed in Patent Document 1 can not lower the adhesive force to an extent sufficient for reworking a thin rolled optical film and a display element.

Patent Document 2 discloses an acrylic pressure-sensitive adhesive composition comprising an acrylic copolymer containing a hydroxyl group but not containing a carboxyl group, a crosslinking agent and a polyether-modified polydimethylsiloxane copolymer having an HLB value of 4 to 13 . However, in the technique disclosed in Patent Document 2, it has been difficult to secure durability.

Patent Documents 3 and 4 disclose a pressure-sensitive adhesive composition comprising a acrylic resin in which a crosslinking agent and a silicate oligomer are blended. However, when the amount of the carboxyl group in the acrylic resin is large, the adhesive force can not be sufficiently lowered. For this reason, the techniques of Patent Documents 3 and 4 can not secure the lithographic properties particularly for a thin, soft optical film and a display element.

JP 2010-275524 A JP 2008-503638 A JP 1996-199130 A JP 1996-209103 A

An object of the present invention is to provide a pressure-sensitive adhesive composition for an optical film that not only can achieve reworkability and reliability, but also has excellent workability.

Another object of the present invention is to provide a pressure-sensitive adhesive layer, a pressure-sensitive optical film, and a display device including the pressure-sensitive adhesive layer formed of the pressure-sensitive adhesive composition for an optical film.

The above and other objects of the present invention can be achieved by the present invention described below.

The pressure-sensitive adhesive composition for an optical film of the present invention comprises a pressure-sensitive adhesive resin having an acid value of 0 mgKOH / g to 20.0 mgKOH / g, a silicate oligomer represented by the following formula (1), and a crosslinking agent.

[Chemical Formula 1]

Wherein R ₁ to R ₄ are each independently hydrogen, an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, X ₁ and X ₂ each independently represent hydrogen, An alkyl group or an aryl group having 6 to 20 carbon atoms, and n is an integer of 1 to 100.

The pressure-sensitive adhesive layer of one embodiment of the present invention may be formed of the pressure-sensitive adhesive composition for an optical film.

The pressure-sensitive adhesive layer of another embodiment of the present invention comprises a pressure-sensitive adhesive resin comprising at least one of a (meth) acrylic polymer, a urethane polymer and a polyester, a pressure-sensitive adhesive layer formed of a composition comprising a silicate oligomer represented by the following formula , And the gel fraction according to the following formula 1 after standing for 1 hour from the formation of the pressure-sensitive adhesive layer at a temperature of 23 캜 and a humidity of 65% RH may be 40% by weight to 95% by weight.

[Chemical Formula 1]

Wherein R ₁ to R ₄ are each independently hydrogen, an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, X ₁ and X ₂ each independently represent hydrogen, An alkyl group or an aryl group having 6 to 20 carbon atoms, n is an integer of 1 to 100,

[Formula 1]

Gel fraction (% by weight) = {(Wc-Wa) / (Wb-Wa)} 100

In the above formula (1), Wb is the weight of the adhesive layer (0.2 g) packed with a fluororesin (TEMISHNTF-1122, manufactured by Nitto Denko) and Wa is the weight of the fluororesin. Further, Wc was obtained by immersing the adhesive layer containing the fluororesin in 40 ml of ethyl acetate at 23 DEG C for 7 days to extract the soluble fraction, drying the adhesive layer on the aluminum cup at 130 DEG C for 2 hours, It is the weight of the adhesive layer wrapped with the fluororesin in which the powder is removed.

The adhesive optical film of the present invention may include one of a polarizer, a protective layer formed on one side of the polarizer, and the adhesive layer formed on the other side of the polarizer.

The display device of the present invention may include the aforementioned adhesive optical film.

INDUSTRIAL APPLICABILITY The present invention has the effect of providing a pressure-sensitive adhesive composition for an optical film, a pressure-sensitive adhesive layer, a pressure-sensitive adhesive optical film, and a display device including the pressure-

1 is a cross-sectional view showing an adhesive optical film according to one embodiment.
Fig. 2 is a cross-sectional view showing another embodiment of the adhesive optical film.
3 is a cross-sectional view showing a display device of one embodiment.
4 is a cross-sectional view showing a display device according to another embodiment.

&Lt; Pressure sensitive adhesive composition for optical film &

The pressure-sensitive adhesive composition for an optical film of the present invention comprises a pressure-sensitive adhesive resin having an acid value of 0 mgKOH / g to 20.0 mgKOH / g, a silicate oligomer and a crosslinking agent. Hereinafter, the composition for forming the pressure-sensitive adhesive composition for an optical film of the specific example will be described.

(A) Adhesive resin

The adhesive resin of one embodiment has an acid value of 0 mgKOH / g to 20 mgKOH / g. For example, the adhesive resin may have an acid value of more than 0 mgKOH / g and not more than 20 mgKOH / g. In the above-mentioned range, the adhesive resin is excellent in adhesion and reliability of the pressure-sensitive adhesive composition and can achieve a balance of reworkability. Specifically, the acid value of the adhesive resin may be 10 mgKOH / g or less, more specifically 3 mgKOH / g or less, and more specifically 1 mgKOH / g or less.

The tacky resin may include a monomer containing a hydroxyl group-containing monomer as a constituent unit as a constituent unit. For example, the hydroxyl group-containing monomer may include (meth) acrylate having a hydroxyl group, a polyol, and the like, but is not limited thereto.

The adhesive resin is not particularly limited as long as it has a tackiness and an acid value of from 0 mgKOH / g to 20 mgKOH / g. Such a viscous resin may include, for example, at least one of (meth) acrylic polymer, urethane polymer and polyester. The adhesive resin may be composed of any one of them, or may be composed of a mixture of these resins. Further, the adhesive resin may be a copolymer of these resins. When such adhesive resin is used, the pressure-sensitive adhesive composition is advantageous for satisfying the optical characteristics of the optical film.

The adhesive resin in one embodiment may include a (meth) acrylic polymer. (Meth) acryl-based polymer is a polymer comprising an alkyl (meth) acrylate monomer as a polymerized unit constituting the main skeleton; Or a copolymer comprising an alkyl (meth) acrylate monomer and other comonomers as polymerized units (hereinafter, alkyl (meth) acrylate copolymer).

The alkyl (meth) acrylate can be exemplified by the monomer having 1 to 18 carbon atoms in the linear or branched alkyl group. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, an amyl group, a hexyl group, a cyclohexyl group, a heptyl group, a 2-ethylhexyl group, A heptyl group, a heptyl group, a heptyl group, a heptyl group, a heptyl group, a heptyl group, a heptyl group, a heptyl group, a heptyl group, a heptyl group, These can be used alone or in combination. Specifically, the average carbon number of these alkyl groups may be 3 to 9.

The alkyl (meth) acrylate copolymer may be prepared by copolymerizing an alkyl (meth) acrylate monomer and at least one comonomer. The comonomer means a monomer capable of polymerizing with an alkyl (meth) acrylate monomer, and is not particularly limited as long as it is polymerizable with the alkyl (meth) acrylate monomer. The one or more comonomers may have a polymerizable functional group having an unsaturated double bond such as a (meth) acryloyl group or a vinyl group. In this case, the adhesive resin can be improved in adhesiveness and heat resistance.

The comonomer may be, for example, 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl Hydroxy group-containing monomers such as 8-hydroxyoctyl acrylate, 10-hydroxydecyl (meth) acrylate, 12-hydroxylauryl (meth) acrylate or (4-hydroxymethylcyclohexyl) -methylacrylate; Carboxyl group-containing monomers such as (meth) acrylic acid, carboxyethyl (meth) acrylate, carboxypentyl (meth) acrylate, itaconic acid, maleic acid, fumaric acid and crotonic acid; Monomers containing acid anhydride groups such as maleic anhydride and itaconic anhydride; Caprolactone adducts of acrylic acid; (Meth) acryloyloxynaphthalene sulfonic acid, sulfopropyl (meth) acrylate, (meth) acryloyloxynaphthalene sulfonic acid, Sulfonic acid group-containing monomers such as sulfonic acid; And phosphoric acid group-containing monomers such as 2-hydroxyethyl acryloyl phosphate and the like.

The comonomer may be, for example, (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N-butyl (meth) acrylamide, N- (N-substituted) amide monomers such as olpropane (meth) acrylamide; Alkylaminoalkyl (meth) acrylate monomers such as aminoethyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate and t-butylaminoethyl (meth) acrylate; (Meth) acrylic acid alkoxyalkyl monomers such as methoxyethyl (meth) acrylate and ethoxyethyl (meth) acrylate; (Meth) acryloyloxymethylenesuccinimide, N- (meth) acryloyl-6-oxyhexamethylenesuccinimide, N- (meth) acryloyl-8- A succinimide-based monomer such as acryloylmorpholine; Maleimide-based monomers such as N-cyclohexylmaleimide, N-isopropylmaleimide, N-laurylmaleimide and N-phenylmaleimide; But are not limited to, N-methyl ethyl ketone, N-methyl itaconimide, N-ethyl itaconimide, N-butyl itaconimide, N-octyl itaconimide, Itaconimide-based monomers such as N, N-lauryl itaconimide; And the like. In this case, the modifying effect of the pressure-sensitive adhesive composition may be obtained.

The comonomer may be, for example, a modified monomer such as vinyl acetate, vinyl propionate, N-vinylpyrrolidone, methylvinylpyrrolidone, vinylpyridine, vinylpiperidone, vinylpyrimidine, vinylpiperazine, vinylpyrazine, vinylpyrrole Vinyl monomers such as vinyl imidazole, vinyl oxazole, vinyl morpholine, N-vinylcarboxylic acid amides, styrene,? -Methylstyrene and N-vinylcaprolactam; Cyanoacrylate monomers such as acrylonitrile and methacrylonitrile; An epoxy group-containing acrylic monomer such as glycidyl (meth) acrylate; Glycolic acid acrylic ester monomers such as (meth) acrylic acid polyethylene glycol, (meth) acrylic acid polypropylene glycol, (meth) acrylic acid methoxyethylene glycol and (meth) acrylic acid methoxypolypropylene glycol; Acrylic acid ester monomers such as (meth) acrylic acid tetrahydrofurfuryl, fluorine (meth) acrylate, silicone (meth) acrylate and 2-methoxyethyl acrylate. It is also possible to use isoprene, butadiene, isobutylene, vinyl ether or the like.

The comonomer may include, for example, a silane-based monomer containing a silicon atom or the like. Silane-based monomers include, for example, 3-acryloxypropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 4-vinylbutyltrimethoxysilane, 4-vinylbutyltriethoxysilane, 8 Vinyl octyltrimethoxysilane, 10-methacryloyloxydecyltrimethoxysilane, 10-acryloyloxydecyltrimethoxysilane, 10-methacryloyloxane, 10-methacryloyloxydecyltrimethoxysilane, Silane triethoxysilane, 10-acryloyloxydecyltriethoxysilane, and the like.

The comonomer may also be selected from the group consisting of tri-propylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, 1,6-hexane diol di (meth) acrylate, bisphenol A diglycidyl (Meth) acrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tri (meth) acrylate, neopentyl glycol di (Meth) acrylic acid such as dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (metha) acrylate, and caprolactone modified dipentaerythritol hexa (meth) acrylate; (Meth) acryloyl groups such as esters of polyhydric alcohols and the like; And a vinyl group; And a polyfunctional monomer having two or more unsaturated double bonds.

The comonomer may be a polyester (meth) acrylate having two or more unsaturated double bonds such as a (meth) acryloyl group and a vinyl group as functional groups similar to the monomer components in the backbone of polyester, epoxy, , Epoxy (meth) acrylate, urethane (meth) acrylate, and the like.

The content of the comonomer is 0% by weight to 20% by weight, 0.1% by weight to 15% by weight, more preferably 0.1% by weight based on the total weight of the whole monomers (monomers used as polymerized units of the alkyl (meth) acrylate copolymer) To 10% by weight. Within this range, the pressure-sensitive adhesive composition is advantageous in terms of both workability and reliability.

The (meth) acrylic copolymer of one specific example may be a comonomer containing a hydroxyl group-containing monomer. In this case, the adhesiveness and durability of the pressure-sensitive adhesive composition can be improved. Since the hydroxyl group-containing monomer is rich in reactivity with the crosslinking agent, the cohesiveness and heat resistance of the pressure-sensitive adhesive composition can be further improved. Further, the hydroxyl group-containing monomer can further improve the workability of the pressure-sensitive adhesive composition. When the monomer containing a hydroxyl group is contained as a comonomer, the proportion thereof may be 0.01 wt% to 15 wt%, 0.03 wt% to 10 wt%, and 0.05 wt% to 7 wt% based on the total weight of the total monomers.

The (meth) acrylic copolymer of another embodiment may use a carboxyl group-containing monomer as a comonomer. In this case, the comonomer can form a reaction point with the crosslinking agent when the pressure-sensitive adhesive composition contains a crosslinking agent. Further, the comonomer can further improve the workability of the pressure-sensitive adhesive composition. When the copolymerizable monomer contains a carboxyl group-containing monomer, the proportion thereof may be 0.05% by weight to 10% by weight, 0.1% by weight to 8% by weight, and 0.2% by weight to 6% by weight based on the total weight of the total monomers.

The (meth) acrylic copolymer of another embodiment may be used in combination with a comonomer containing a hydroxyl group and a carboxyl group-containing monomer as a comonomer.

In an embodiment, the (meth) acrylic polymer may have a weight average molecular weight of 300,000 to 300. Specifically, the weight average molecular weight of the (meth) acrylic polymer may be from 500,000 to 250,000, more specifically from 800,000 to 230,000. In this case, the pressure-sensitive adhesive composition can have improved durability and heat resistance. More specifically, the weight average molecular weight of the (meth) acrylic polymer may be 700,000 to 230. Within this range, the pressure-sensitive adhesive composition can be further improved in heat resistance and can be advantageous in coating due to its appropriate viscosity. In addition, the process of injecting a large amount of the diluting solvent can be omitted, and the cost can be reduced. In the present specification, the weight average molecular weight means a value calculated by GPC (gel permeation chromatography) and calculated by polystyrene conversion.

The glass transition temperature of the (meth) acrylic polymer in one embodiment may be -10 캜 or lower and -25 캜 or lower. Within this range, the pressure-sensitive adhesive composition can have improved flexibility and initial tackiness, and can exhibit sufficient adhesion even at low pressures. The lower limit of the glass transition temperature may be -100 DEG C or higher, -80 DEG C or higher, or -70 DEG C or higher. Within this range, deterioration of the heat resistance of the polyester can be prevented.

The polymerization method of the (meth) acrylic polymer can be suitably selected from known polymerization methods such as solution polymerization, bulk polymerization, emulsion polymerization, various kinds of radical polymerization and the like. The (meth) acrylic polymer obtained by the polymerization method may be any of a random copolymer, a block copolymer and a graft copolymer.

In one embodiment, the (meth) acrylic polymer may be prepared by solution polymerization. In this case, for example, ethyl acetate, toluene and the like may be used as the polymerization solvent. Specifically, the solution polymerization can be carried out under the reaction conditions of usually about 50 ° C to 85 ° C for about 5 hours to 30 hours by adding a polymerization initiator under an inert gas stream such as nitrogen.

In another embodiment, the (meth) acrylic polymer may be prepared by radical polymerization. The polymerization initiator, chain transfer agent, and emulsifier used in the radical polymerization are not particularly limited and can be appropriately selected and used. The weight average molecular weight of the (meth) acrylic polymer can be controlled by adjusting the amount of the polymerization initiator, the chain transfer agent, and the like, and the reaction conditions. Examples of the polymerization initiator include 2,2'-azobisisobutyronitrile, 2,2'-azobis (2-amidinopropane) dihydrochloride, 2,2'-azobis [2- (5- Azobis (2-methylpropionamidine) bisulfate, 2,2'-azobis (N, N'-dicyclohexylcarbodiimide) An azo initiator such as 2,2'-azobis [N- (2-carboxyethyl) -2-methylpropionamidine] hydrate (VA-057 manufactured by Wako Pure Chemical Industries, An initiator, a combination of a persulfate and sodium hydrogen sulfite, a combination of a peroxide and sodium ascorbate, or a combination of a peroxide and a reducing agent, but the present invention is not limited thereto.

The polymerization initiator may be used alone or in combination of two or more. The content of the polymerization initiator may be, for example, 0.005 parts by weight to 1 part by weight and 0.02 parts by weight to 0.5 parts by weight based on 100 parts by weight of the total monomers. For example, the (meth) acrylic polymer (A) having a weight average molecular weight as described above can be prepared by using 2,2'-azobisisobutyronitrile as a polymerization initiator. In this case, the specific amount of the polymerization initiator to be used may be 0.06 part by mass to 0.2 part by mass, or 0.08 part by mass to 0.175 part by mass with respect to 100 parts by mass of the total amount of the monomer component.

Examples of the chain transfer agent include lauryl mercaptan, glycidylmercaptan, mercaptoacetic acid, 2-mercaptoethanol, thioglycolic acid, 2-ethylhexyl thioglycolate, 2,3-dimercapto- -Propanol and the like. The chain transfer agent may be used alone, or two or more kinds may be used in combination. The content of the chain transfer agent may be 0.1 parts by weight or less based on 100 parts by weight of the total monomer components.

Examples of the emulsifier include anionic emulsifiers such as sodium lauryl sulfate, ammonium lauryl sulfate, sodium dodecylbenzenesulfonate, ammonium polyoxyethylene alkylether sulfate, and sodium polyoxyethylene alkylphenylether sulfate, polyoxyethylene Nonionic emulsifiers such as alkyl ethers, polyoxyethylene alkyl phenyl ethers, polyoxyethylene fatty acid esters and polyoxyethylene-polyoxypropylene block polymers. These emulsifiers may be used alone or in combination of two or more. Examples of the emulsifier to which a radically polymerizable functional group such as a propenyl group or an allyl ether group is introduced as the reactive emulsifier include Aquarons HS-10, HS-20, KH-10, BC-05, BC-10 and BC-20 (all of which are manufactured by DAI-ICHI KOGYO SEIYAKU), Adekaria soap SE10N and SR-10N (manufactured by ADEKA CHEMICAL Co., Ltd.) The emulsifier is used in an amount of 0.3 to 5 parts by weight based on 100 parts by weight of the total amount of the monomer components and 0.5 parts by weight or more based on the polymerization stability and mechanical stability, To 2 parts by weight.

The following describes the urethane polymer. In one embodiment, the urethane polymer that can be used as the adhesive resin may be, for example, a polyol and an isocyanate. Specifically, examples of the polyol include a polyester polyol and a polyether polyol.

As the polyester polyol, a known polyester polyol may be used.

The polyester polyol in one embodiment can be obtained by dehydration polymerization of an acid component and a polyol component having two or more hydroxyl groups. Examples of the acid component include terephthalic acid, adipic acid, azelaic acid, sebacic acid, phthalic anhydride, isophthalic acid and trimellitic acid. The polyol component having a valence of two or more is, for example, ethylene glycol, propylene glycol, diethylene glycol, butylene glycol, 1,6-hexane glycol, 3-methyl- Diol, 3,3'-dimethylolheptane, polyoxyethylene glycol, polyoxypropylene glycol, 1,4-butanediol, neopentylglycol, 2-butyl- , 5-pentanediol, 2-butyl-4-ethyl-1,5-pentanediol, and the like; Trihydric alcohols including glycerin and trimethylol propane; And tetravalent alcohols including pentaerythritol and the like.

In another embodiment, the polyester polyol may be a polyester polyol obtained by ring-opening polymerization of lactones such as polycaprolactone, poly (beta -methyl- gamma -valerolactone), polyvalerolactone and the like.

The molecular weight of the polyester polyol can be from low molecular weight to high molecular weight. Specifically, a polyester polyol having a molecular weight of 1,000 to 5,000, more specifically, a polyester polyol having a molecular weight of 2,500 to 3,500 can be used. Within this range, the polyester polyol can prevent gelation of the polyurethane and improve the cohesive force of the polyurethane itself. The amount of the polyester polyol to be used may be 10 mol% to 70 mol%, more specifically 35 mol% to 65 mol%, of the polyol constituting the polyurethane.

As the polyether polyol, a known polyether polyol may be used.

The polyether polyol in one embodiment can be obtained by using a low molecular weight polyol such as propylene glycol, ethylene glycol, glycerin, trimethylol propane or the like as an initiator, for example, ethylene oxide, propylene oxide, butylene oxide, And a polyether polyol obtained by polymerizing an oxirane compound such as tetrahydrofuran. Specifically, the polyether polyol can be exemplified by those having two or more functional groups including polypropylene glycol, polyethylene glycol, polytetramethylene glycol, and the like.

In another embodiment, the initiator is selected from the group consisting of glycols such as ethylene glycol, 1,4-butanediol, neopentyl glycol, butyl ethyl pentane diol, glycerine, trimethylol propane, pentaerythritol, ; And polyvalent amines such as ethylenediamine, N-aminoethylethanolamine, isophoronediamine, xylylenediamine, and the like can be used in combination.

The molecular weight of the polyether polyol can be from low molecular weight to high molecular weight. The polyether polyol may specifically have a weight average molecular weight of 1,000 to 5,000, more specifically 2,500 to 3,500. Within the above range, the polyether polyol can prevent the gelation of the urethane polymer and improve the cohesive force of the polyurethane itself.

The content of the polyether polyol may be 20 to 80 mol%, more specifically 40 to 65 mol%, of the polyol constituting the polyurethane.

In one embodiment, the polyether polyol may also be a bifunctional polyether polyol. In another embodiment, the polyether polyol may comprise a polyether polyol having a molecular weight of 1,000 to 5,000 and at the same time having at least three hydroxyl groups in one molecule. In such a case, the polyether polyol can achieve a balance of adhesive force and re-peelability to the urethane polymer. In another embodiment, the polyether polyol has a molecular weight of 2,500 to 3,500, and at least some of the polyols having at least three functionalities can be utilized. In this case, the polyether polyol can prevent the gelation of the urethane polymer, improve the reactivity, and improve the cohesion of the polyurethane itself.

The isocyanate used in one embodiment may be an organic polyisocyanate compound including a known aromatic polyisocyanate, aliphatic polyisocyanate, aromatic aliphatic polyisocyanate, alicyclic polyisocyanate and the like.

Examples of the aromatic polyisocyanate include 1,3-phenylene diisocyanate, 4,4'-diphenyl diisocyanate, 1,4-phenylene diisocyanate, 4,4'-diphenylmethane diisocyanate, Tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4'-toluidine diisocyanate, 2,4,6-triisocyanate toluene, 1,3,5-triisocyanate benzene, dianisidine diisocyanate , 4,4'-diphenyl ether diisocyanate, 4,4 ', 4 "-triphenylmethane triisocyanate, and the like.

The aliphatic polyisocyanate is selected from the group consisting of trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, 1,2-propylene diisocyanate, 2,3-butylene diisocyanate, Dodecamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, and the like.

The aromatic aliphatic polyisocyanate is selected from the group consisting of ω, ω'-diisocyanate-1,3-dimethylbenzene, ω'-diisocyanate-1,4-dimethylbenzene, ω'-diisocyanate- Ethyl benzene, 1,4-tetramethyl xylylene diisocyanate, 1,3-tetramethyl xylylene diisocyanate, and the like.

Alicyclic polyisocyanates include 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate, 1,3-cyclopentane diisocyanate, 1,3-cyclohexane diisocyanate, 1,4-cyclohexane diisocyanate, methyl Cyclohexane diisocyanate, methyl-2,6-cyclohexane diisocyanate, 4,4'-methylene bis (cyclohexyl isocyanate), 1,4-bis (isocyanatomethyl) cyclohexane, 1,4- Bis (isocyanatomethyl) cyclohexane, and the like.

The isocyanate may also be used in combination with a trimethylol propane adduct of the polyisocyanate, a buret resin reacted with water, a trimer having an isocyanurate ring, and the like.

In one embodiment, the polyisocyanate is selected from, for example, 4,4'-diphenylmethane diisocyanate, hexamethylene diisocyanate, 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate (isophorone diisocyanate ) Can be used.

As the catalyst used for synthesis of the urethane polymer, a known catalyst can be used. Examples thereof include tertiary amine compounds and organometallic compounds.

Examples of the tertiary amine compound include triethylamine, triethylenediamine, 1,8-diazabicyclo (5,4,0) -undecene-7 (DBU), and the like.

Examples of the organometallic compounds include tin-based compounds and non-saponified compounds. Tin-based compounds include dibutyltin dichloride, dibutyltin oxide, dibutyltin dibromide, dibutyltin dicarylate, dibutyltin dilaurate (DBTDL), dibutyltin diacetate, dibutyltin sulfide, Tributyl tin oxide, tributyl tin acetate, triethyl tin ethoxide, tributyl tin ethoxide, dioctyl tin oxide, tributyltin chloride, tributyltin trichloroacetate, 2-ethylhexane Tin oxide, and the like.

Examples of the non-saponific compound include titanium-based compounds such as dibutyltitanium dichloride, tetrabutyl titanate and butoxy titanium trichloride, lead compounds such as lead oleate, lead 2-ethylhexanoate, lead benzoate and lead naphthene, Iron compounds such as iron acetate such as 2-ethylhexanoate and iron acetylacetonate, cobalt compounds such as cobalt benzoate and cobalt 2-ethylhexanoate, zinc compounds such as zinc naphthenate and zinc 2-ethylhexanoate, and zirconium naphthenate .

In the synthesis of one embodiment of the urethane polymer, the reaction time of the urethane polymer can be shortened if one or more of the above examples is used.

When two or more of the above catalysts are used in combination in the urethane polymer synthesis of another specific example, gelation of the urethane polymer can be prevented and the turbidity of the reaction solution can be lowered. In particular, when a urethane polymer is synthesized by using a polyester polyol and a polyether polyol having different reactivity as a polyol, the anti-gelation effect can be further improved. Further, when two or more of the above catalysts are used, it is possible to control the reaction rate of urethane polymer synthesis, the selectivity of the catalyst, and the like. As the combination of two or more catalysts, a tertiary amine / organometallic system, a tin system / a non-silicon system, a tin system / a tin system and the like can be used. Specific examples thereof include tin / tin system, more specifically, dibutyltin dilaurate A combination of tin 2-ethylhexanoate may be used.

In one embodiment, when the combination of dibutyltin dilaurate and 2-ethylhexanoate is used as a catalyst for the synthesis of urethane polymers, the weight ratio of dibutyltin dilaurate: 2-ethylhexanoate to tin is 1: 1 &Lt; / RTI > Specifically, it may be from 1: 0.2 to 1: 0.6. Within the above range, the effect of lowering the gelation of the urethane polymer can be further improved.

The amount of the catalyst used may be 0.01% by weight to 1.0% by weight based on the total amount of the polyol and the isocyanate.

The polyurethane in one embodiment can be used in combination with a polyfunctional isocyanate compound. The polyfunctional isocyanate compound may include, for example, the above-mentioned organic polyisocyanate compounds and their trimethylol propane adducts, burettes reacted with water, or trimer having an isocyanurate ring and the like.

In one embodiment, when a urethane polymer and a polyfunctional isocyanate are used in combination, the polyfunctional isocyanate may be included in an amount of 1 to 20 parts by weight based on 100 parts by weight of the urethane polymer. Specifically, it is 2 parts by weight to 10 parts by weight. Within the above range, the adhesive force and the cohesive force of the adhesive resin including the urethane polymer can be further improved.

The reaction temperature in the synthesis of the urethane polymer in one specific example may be 100 ° C or less. More specifically from 85 [deg.] C to 95 [deg.] C. Within the above range, it is advantageous to control the crosslinking structure of the urethane polymer, and thereby a polyurethane having a predetermined molecular weight and chemical structure can be obtained.

The polyurethane of one embodiment may have a weight average molecular weight of 10,000 to 200,000, 15,000 to 100,000, and 20,000 to 50,000. Within the above range, the adhesive force and the cohesive force of the adhesive resin including the urethane polymer can be further improved, and the heat resistance and the mechanical strength can be further improved. Within the above range, the flexibility of the adhesive resin can be prevented from disappearing, and the initial tackiness and the total adhesive force can be improved. In this case, the pressure-sensitive adhesive composition can be easily adhered even at a low pressure.

The glass transition temperature of the polyurethane in one embodiment may be -10 占 폚 or lower and -25 占 폚 or lower. Within this range, the flexibility of the adhesive resin can be prevented from disappearing, and the initial tackiness and the total adhesive force can be improved. In this case, the pressure-sensitive adhesive composition can be easily adhered even at a low pressure. In addition, the glass transition temperature may specifically be a lower limit of -100 DEG C or higher, -80 DEG C or higher, or -70 DEG C or higher. Within this range, the heat resistance of the adhesive resin can be further improved.

In one embodiment, as the solvent used for diluting the urethane polymer, a known solvent may be used. Examples of the solvent include water, methyl ethyl ketone, ethyl acetate, toluene, xylene, and acetone. In one embodiment, toluene can be used as the solvent. In this case, the solubility of the urethane polymer and the boiling point of the solvent may be excellent.

The following describes the polyester. The polyester of one specific example can be obtained by using a polyol component and a carboxylic acid component as raw materials and polycondensation thereof.

In one embodiment, the polyol component used in the synthesis of the polyester may include at least one of a diol having an alkoxy group in the side chain and a polyol other than a diol having an alkoxy group in the side chain.

The diol having an alkoxy group in the side chain is preferably selected from the group consisting of methoxyethylene glycol, methoxypropylene glycol, methoxybutylene glycol, ethoxyethylene glycol, ethoxypropylene glycol, ethoxybutylene glycol Diethoxyethylene glycol, dimethoxypropylene glycol, dimethoxybutylene glycol, diethoxyethylene glycol, diethoxypropylene glycol, diethoxybutylene glycol, and the like can be used. It is not suggested.

Examples of the polyol other than the diol having an alkoxy group in the side chain include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol , Straight-chain aliphatic diols such as 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, and 1,10-decanediol; Methyl-1, 3-propanediol, 2,2-diethyl-1,3-propanediol, 2-methyl- Methyl-1,5-pentanediol, 2-methyl-2,4-pentanediol, 2,4-diethyl-1,5- An aliphatic diol having a hydrocarbon group side chain such as pentane diol, 1,3,5-trimethyl-1,3-pentane diol and 2-methyl-1,6-hexane diol. These may be used alone or in combination of two or more.

In one embodiment, the polyol other than the diol having an alkoxy group in the side chain includes a straight chain aliphatic diol having 2 to 6 carbon atoms, specifically 1,4-butanediol, 1,6-hexanediol, Or an aliphatic diol having a hydrocarbon group side chain having 1 to 4 carbon atoms, more specifically neopentyl glycol. In this case, the initial tackiness, mechanical strength, and heat resistance of the pressure-sensitive adhesive composition can be well balanced.

The polyol component used in the synthesis of the polyester as needed may further comprise at least one of a polyether diol and a trihydric or higher polyhydric alcohol.

Examples of the polyether diol include polyethylene glycol, polypropylene glycol, and polytetramethylene glycol obtained by ring-opening polymerization of ethylene oxide, propionoxide, tetrahydrofuran, etc., Two or more species can be used.

Examples of the trihydric or higher polyhydric alcohol include trimethylolethane, trimethylolpropane, glycerine, pentaerythritol, 1,2,4-butanetriol, 1,2,5-pentanetriol, Hexanetriol, and 6-hexanetriol. These may be used alone or in combination. In one embodiment, trimethylolpropane may be used in the trivalent or higher polyhydric alcohols described above. In this case, the polyester can further improve the heat resistance. The content of the polyvalent alcohol having a trivalent or more is not particularly limited, but may be, for example, 0.1 mol% to 5.0 mol% and 0.5 mol% to 3.0 mol%.

The carboxylic acid component used in the synthesis of the polyester is not particularly limited. For example, a carboxylic acid having an alkoxy group in the side chain may be included. In this case, an alkoxy group can be introduced into the side chain of the obtained polyester-based resin.

Of course, any of the above-mentioned polyol component and carboxylic acid component can use a raw material component containing an alkoxy group in the side chain.

Examples of the carboxylic acid having an alkoxy group in the side chain include polyvinyl ether described in Japanese Patent Application Laid-Open No. 2004-307462.

In one embodiment, among the examples of the above-mentioned carboxylic acid, a carboxylic acid having an alkoxy group and having a number average molecular weight of 500 to 3,000 can be used. In this case, the polyester can be well balanced in terms of initial stickiness, mechanical strength and heat resistance.

Examples of the carboxylic acid other than the carboxylic acid having an alkoxy group in the side chain include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, orthophthalic acid, 1,5-naphthalene dicarboxylic acid, 2,6-naphthalene dicarboxylic acid, Saturated dicarboxylic acids such as aliphatic dicarboxylic acids such as succinic acid, glutaric acid, adipic acid, azelaic acid, sebacic acid, decanedicarboxylic acid and octadecanedicarboxylic acid; And unsaturated dicarboxylic acids such as maleic acid, fumaric acid, maleic acid, itaconic acid, tetrahydrophthalic acid, tetrachlorophthalic acid, hexahydrophthalic acid and dimeric acids, and these may be used singly or in combination.

The carboxylic acid component in one specific example may be a trivalent or more, such as trimellitic acid, trimesic acid, pyromellitic acid, 1,2,4-butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, And may further include a carboxylic acid. Among them, an aromatic dicarboxylic acid, specifically, terephthalic acid, isophthalic acid, an aliphatic dicarboxylic acid having 6 to 12 carbon atoms (including carbon of a carboxyl group), and more specifically sebacic acid can be used. In this case, the polyester can balance the initial tackiness, mechanical strength and heat resistance of the pressure-sensitive adhesive composition in a good balance.

The content of the alkoxy group in the polyester resin in one specific example is not particularly limited, but it is possible to introduce about 5 to 300 and 60 to 150 alkoxy groups per one molecule of the polyester resin. Within this range, the initial adhesive strength, mechanical strength, and heat resistance of the pressure-sensitive adhesive composition can be further improved.

In the synthesis of the polyester, the mixing ratio of the polyol component may be 1 equivalent or more, 1.2 equivalents or more and 2.0 equivalents or less per 1 equivalent of the carboxylic acid component. Within the above range, the molecular weight of the polyester can be adjusted to an appropriate range, and the yield can be further improved.

In the polycondensation reaction of the polyester, the condensation reaction may be performed after the polymerization (esterification) reaction is performed first. In such a polymerization (esterification) reaction, a catalyst may be used. As the catalyst for the esterification reaction, specifically, a catalyst such as a titanium-based catalyst such as tetraisopropyl titanate or tetrabutyl titanate, a germanium-based catalyst such as antimony-based catalyst or germanium oxide-based catalyst or a catalyst such as zinc acetate, manganese acetate, dibutyltin Oxides, and the like, and one or more of these may be used.

The compounding amount of the esterification catalyst may be 1 ppm to 10,000 ppm, 10 ppm to 5,000 ppm, and 10 ppm to 3,000 ppm with respect to the total amount of all reactants. Within the above range, the effect of improving the polymerization degree of the reaction, shortening the reaction time, and further lowering the side reaction can be realized.

The reaction temperature in the polymerization (esterification) reaction may be 160 ° C to 260 ° C, specifically 180 ° C to 250 ° C, more specifically 200 ° C to 250 ° C. Within the above range, the effect of improving the polymerization degree of the reaction, shortening the reaction time, and further lowering the side reaction can be realized. In addition, the polymerization (esterification) reaction can be carried out under atmospheric pressure.

In one embodiment, after the polymerization (esterification) reaction is carried out, a condensation reaction can be carried out. At this time, an additional catalyst may be further added. The catalyst used in the condensation reaction in the synthesis of polyester can be used in the same amount as the catalyst used in the esterification reaction described above. Concretely, the condensation reaction may be carried out at a reaction temperature of 220 to 260 ° C, more specifically 230 to 250 ° C, and the reaction may be carried out at a final pressure of 5 hPa or less. Within this reaction temperature range, the reactivity of the reactants can be improved and side reactions such as decomposition of the polyester can be further lowered.

The polyester of one embodiment may have a weight average molecular weight of 10,000 to 200,000, 15,000 to 100,000, and 20,000 to 50,000. Within the range of the weight average molecular weight, a sufficient cohesive force can be obtained when applied as a pressure sensitive adhesive composition, and more excellent heat resistance and mechanical strength can be secured. Also within the above range, the pressure-sensitive adhesive composition can have improved flexibility and initial tackiness, and can exhibit sufficient adhesion even at low pressure.

The glass transition temperature of the polyester in one embodiment may be -10 占 폚 or lower and -25 占 폚 or lower. Within this range, the pressure-sensitive adhesive composition can have improved flexibility and initial tackiness, and can exhibit sufficient adhesion even at low pressures. The lower limit of the glass transition temperature may be -100 DEG C or higher, -80 DEG C or higher, or -70 DEG C or higher. Within this range, deterioration of the heat resistance of the polyester can be prevented.

In one embodiment, a known solvent may be used as the solvent for diluting the polyester. Examples of the solvent include water, methyl ethyl ketone, ethyl acetate, toluene, xylene, and acetone. In one embodiment, methyl ethyl ketone and ethyl acetate may be used as the solvent. In this case, the solubility of the polyester and the boiling point of the solvent may be excellent.

(B) Silicate Oligomer

The silicate oligomer of one embodiment is represented by the following formula (1).

Wherein R ₁ to R ₄ are each independently hydrogen, an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, X ₁ and X ₂ each independently represent hydrogen, An alkyl group or an aryl group having 6 to 20 carbon atoms, and n is an integer of 1 to 100. The alkyl group and the aryl group may be substituted or unsubstituted. Further, the alkyl group may be a straight chain structure or a branched chain structure. Specifically, each of R ₁ to R ₄ independently represents an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 12 carbon atoms, X ₁ and X ₂ each independently represent hydrogen, an alkyl group having 1 to 6 carbon atoms, 12 < / RTI > For example, R ₁ to R ₄ each independently may be a methyl group, an ethyl group, or a phenyl group.

Specifically, the silicate oligomer may be a single oligomer or a mixture of plural oligomers.

The weight average molecular weight of the silicate oligomer may be from 300 to 30,000. When the weight-average molecular weight of the silicate oligomer is within this range, the pressure-sensitive adhesive composition can be compatible with a further superior level of reworkability and adhesiveness.

In a specific example, the silicate oligomer is a silicate oligomer in which R ₁ to R ₄ , X ₁ and X ₂ in the general formula (1) are methyl groups and weight average molecular weights are 300 to 20,000, R ₁ to R ₄ , X ₁ and X _A silicate oligomer having a weight average molecular weight of not less than 20,000 but not more than 30,000 and a silicate oligomer wherein R ₁ , R ₂ , R ₃ , R ₄ , X ₁ or X ₂ in the formula 1 include a phenyl group .

Methyl silicate oligomer having a weight average molecular weight of 300 to 20,000, methyl silicate oligomer having a weight average molecular weight of more than 20,000 and 30,000 or less, or R ₁ , R ₂ , R ₃ , R ₄ , X ₁ or X ₂ of formula , The pressure-sensitive adhesive composition may be compatible with a level of more excellent reworkability and adhesiveness.

The weight average molecular weight of the silicate oligomer may be specifically from 500 to 25,000, more specifically from 600 to 5,000, and more specifically from 800 to 3,500.

The adhesive resin Silicate Mixing ratio of oligomers

The pressure-sensitive adhesive composition according to one embodiment may include 0.01 to 50 parts by weight of silicate oligomer relative to 100 parts by weight of the pressure-sensitive adhesive resin. Within the above-mentioned range, the pressure-sensitive adhesive composition can be compatible with a further superior level of reworkability and adhesiveness. In a specific example, the silicate oligomer is added in an amount of 0.01 to 50 parts by weight, specifically 0.5 to 20 parts by weight, more specifically 0.5 to 10 parts by weight, more specifically 1 part by weight To 5 parts by weight. Within the above range, the initial reworkability and adhesive force after heating of the pressure-sensitive adhesive composition can be further improved.

Cross-linking agent

The pressure-sensitive adhesive composition of one embodiment may contain a crosslinking agent.

As the crosslinking agent, an organic crosslinking agent or a polyfunctional metal chelate can be used. Examples of the organic crosslinking agent include an isocyanate crosslinking agent, a carbodiimide crosslinking agent, an oxazoline crosslinking agent, a peroxide crosslinking agent, an epoxy crosslinking agent, and an imine crosslinking agent. As the polyfunctional metal chelate, it is exemplified that the polyvalent metal is covalently bonded or coordinated with the organic compound. Examples of the multivalent metal atom include Al, Cr, Zr, Co, Cu, Fe, Ni, V, Zn, In, Ca, Mg, Mn, Y, Ce, Sr, Ba, Mo, La, . Examples of the organic compound include an alkyl ester, an alcohol compound, a carboxylic acid compound, an ether compound, a ketone compound and the like.

In an embodiment, the cross-linking agent may be at least one of an isocyanate cross-linking agent, a carbodiimide cross-linking agent, and a peroxide cross-linking agent. When a peroxide-based crosslinking agent is used, an adhesive layer which does not require aging can be produced. A pressure-sensitive adhesive layer which does not require aging is strongly demanded from the viewpoint of handling improvement in the production process of the pressure-sensitive adhesive layer. Therefore, the need for aging of the pressure-sensitive adhesive layer is a great advantage in the manufacturing process. The adhesive layer, which does not require aging, is advantageous in that it is excellent in reworkability and reliability and improves handling properties in the process of manufacturing the adhesive layer.

Examples of the isocyanate crosslinking agent include isocyanate monomers such as tolylene diisocyanate, chlorophenylene diisocyanate, tetramethylene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, and hydrogenated diphenylmethane diisocyanate, or isocyanate monomers such as isocyanate monomers An isocyanate compound added with trimethylolpropane or the like; And isocyanurate or isocyanate biuret type isocyanate and urethane prepolymer type isocyanate reacted with polyether polyol, polyester polyol, acrylic polyol, polybutadiene polyol, polyisoprene polyol and the like; &Lt; / RTI >

Specifically, the isocyanate crosslinking agent may be a polyisocyanate compound, and more specifically, it may be a polyisocyanate compound selected from the group consisting of hexamethylene diisocyanate, hydrogenated xylylene diisocyanate and isophorone diisocyanate, or a polyisocyanate compound derived therefrom . The polyisocyanate compound selected from the group consisting of hexamethylene diisocyanate, hydrogenated xylylene diisocyanate and isophorone diisocyanate or a polyisocyanate compound derived therefrom is at least one selected from the group consisting of hexamethylene diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate, Methylene diisocyanate, polyol-modified hydrogenolylylene diisocyanate, trimeric hydrogenolylylene diisocyanate, and polyol-modified isophorone diisocyanate. The polyisocyanate compounds exemplified above may be excellent in the crosslinking reaction rate with the hydroxyl group. In addition, the exemplified polyisocyanate compound can contribute to accelerated crosslinking particularly because the crosslinking reaction can proceed rapidly using an acid or a base contained in the polymer as a catalyst.

As the carbodiimide-based crosslinking agent, a compound having two or more carbodiimide groups (-N═C═N-) in the molecule may be specifically used, and known polycarbodiimide compounds may be used. The carbodiimide compound can be, for example, a high molecular weight polycarbodiimide produced by a decarbonic acid condensation reaction of a diisocyanate in the presence of a carbodiimidization catalyst. More specifically, the polycarbodiimide compound may be a decarboxylic acid condensation reaction of the following diisocyanate.

The diisocyanates used in the polycarbodiimide compound include 4,4'-diphenylmethane diisocyanate, 3,3'-dimethoxy-4,4'-diphenylmethane diisocyanate, 3,3'-di Methyl-4,4'-diphenylmethane diisocyanate, 4,4'-diphenyl ether diisocyanate, 3,3'-dimethyl-4,4'-diphenyl ether diisocyanate, 2,4- One of isocyanate, 2,6-tolylene diisocyanate, 1-methoxyphenyl-2,4-diisocyanate, isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate and tetramethyl xylylene diisocyanate Or more can be used. Further, a mixture of two or more of the above examples may be used.

The catalysts used in the carbodiimidization reaction include 1-phenyl-2-phosphorene-1-oxide, 3-methyl-2-phosphorene- Phosphorane-1-oxide, 1-ethyl-2-phosphorene-1-oxide, or their 3-phosphorene isomers.

Examples of the high molecular weight polycarbodiimide compound in the specific examples include Cabodite series manufactured by Nisshinbo Sekiki Co., Ltd. Among them, when carboditlite V-01, 03, 05, 07, 09 is used, compatibility with an organic solvent can be excellent.

The peroxide-based crosslinking agent can be used without limitation as long as it generates radical-active species by heating or light irradiation to promote crosslinking of the base polymer of the pressure-sensitive adhesive composition. Concretely, a peroxide-based cross-linking agent having a one-minute half-life temperature of 50 ° C to 160 ° C or 60 ° C to 140 ° C may be used. In this case, workability and stability can be improved.

Specifically, the peroxide-based crosslinking agent is selected from, for example, di (2-ethylhexyl) peroxydicarbonate (1 minute half life temperature: 90.6 占 폚), die (4-t- butyl cyclohexyl) peroxydicarbonate : 92.1 占 폚), di-sec-butyl peroxydicarbonate (one minute half life temperature: 92.4 占 폚), t-butyl peroxyneodecanoate (one minute half life temperature: 103.5 占 폚), t-hexyl peroxy pivalate (One minute half life temperature: 109.1 占 폚), t-butyl peroxypivalate (one minute half life temperature: 110.3 占 폚), diarooyl peroxide (one minute half life temperature: 116.4 占 폚), di-n-octanoyl peroxide (Half-life temperature for one minute: 117.4 占 폚), 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate (half-life temperature for one minute: 124.3 占 폚), di (4-methylbenzoyl) peroxide 1 minute half-life temperature: 128.2 占 폚), dibenzoyl peroxide (one minute half life temperature: 130.0 占 폚), t-butyl peroxyisobutyrate Cold temperature: 136.1 ℃), 1,1- di (t--hexylperoxy) cyclohexane (one minute half life temperature: 149.2 ℃, and the like). Among them, di (4-t-butylcyclohexyl) peroxydicarbonate (1 minute half-life temperature: 92.1 占 폚), diarooyl peroxide (1 minute half life temperature: 116.4 占 폚) Dibenzoyl peroxide (one-minute half-life temperature: 130.0 占 폚) and the like are specifically used.

The peroxide half-life is an index indicating the rate of decomposition of peroxide, and refers to the time until the amount of peroxide remaining is halved. In one embodiment, the decomposition temperature, half-life period, and the like of the peroxide can be, for example, as described in each maker catalog. For example, it is described in " Organic Peroxide Catalog Ninth Edition (May 2003) " by Nippon Oil &

The oxazoline crosslinking agent specifically includes 2-isopropyl-2-oxazoline, 2-vinyl-2-oxazoline, 2-vinyl- 2-oxazoline, 2-isopropenyl-2-oxazoline, 2-isopropenyl-4-methyl-2-oxazoline and 2-isopropenyl- , But is not limited thereto. As the oxazoline crosslinking agent, those sold commercially can be used. For example, oxazoline group-containing acrylic polymers such as epocros WS-300, epocros WS-500, epocros WS-700, epocros K-1000 series and epocros K-2000 series of Nippon Catalysts may be used singly or in combination of two or more But is not limited thereto.

The amount of the crosslinking agent to be used may be 0.01 to 20 parts by weight, more preferably 0.03 to 10 parts by weight, based on 100 parts by weight of the adhesive resin. Within this range, the cohesive force of the pressure-sensitive adhesive composition is excellent, the rate of foaming during heating can be lowered, the moisture resistance is excellent, and the workability can be improved in a reliability test or the like.

In one specific example, as the crosslinking agent, one type of isocyanate crosslinking agent may be used alone, or two or more kinds of crosslinking agents may be used. The content of the isocyanate-based crosslinking agent in this specific example may be 0.01 to 2 parts by weight, 0.02 to 2 parts by weight and 0.05 to 1.5 parts by weight based on 100 parts by weight of the adhesive resin. Within the above range, the cohesive force of the pressure-sensitive adhesive composition and the reworkability in the durability test can be further improved.

In another embodiment, the peroxide-based crosslinking agent may be used alone or as a mixture of two or more thereof as the crosslinking agent. When a peroxide-based crosslinking agent is used, an adhesive layer which does not require aging can be produced. A pressure-sensitive adhesive layer that does not require aging is strongly demanded from the viewpoint of handling improvement in the production process of the pressure-sensitive adhesive layer. Therefore, the fact that aging of the pressure-sensitive adhesive layer is not required is a great advantage in the manufacturing process. The adhesive layer, which does not require aging, is advantageous in that it is excellent in reworkability and reliability and improves handling properties in the process of manufacturing the adhesive layer.

The content of the peroxide-based crosslinking agent in this specific example is 0.01 to 2 parts by weight, preferably 0.02 to 2 parts by weight, 0.04 to 1.5 parts by weight, and 0.05 to 5 parts by weight, relative to 100 parts by weight of the adhesive resin. 1 part by weight. Within the above range, the processability, reworkability, crosslinking stability, retentivity and the like of the pressure-sensitive adhesive composition can be further improved.

Silane coupling agent

The pressure sensitive adhesive composition of one embodiment may further contain a silane coupling agent. When a silane coupling agent is used, the durability of the pressure-sensitive adhesive composition can be further improved. Silane coupling agents include, for example, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 2- (3,4- Silane coupling agents such as epoxy group-containing silane coupling agents such as trimethoxysilane and cyclohexyltrimethoxysilane, 3-aminopropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, 3- Amino group-containing silane coupling agents such as N- (1,3-dimethylbutylidene) propylamine and N-phenyl- -aminopropyltrimethoxysilane, 3-acryloxypropyltrimethoxysilane, 3- (Meth) acrylic group-containing silane coupling agents such as triethoxysilane and (meth) acryloxypropyltriethoxysilane, and isocyanate group-containing silane coupling agents such as 3-isocyanatepropyltriethoxysilane. The silane coupling agent may be used singly or in combination of two or more kinds.

The content of the silane coupling agent is 0.001 to 10 parts by weight, 0.001 to 5 parts by weight, 0.01 to 1 part by weight, 0.02 to 1 part by weight, 0.05 to 1 part by weight, By weight to 0.6 parts by weight. Within the above range, the durability of the pressure-sensitive adhesive composition can be improved, and adhesion to an optical member such as a liquid crystal cell can be ensured.

In addition, the pressure-sensitive adhesive composition of one embodiment may further include additives other than the above-mentioned components. For example, the additive may be selected from polyether compounds of polyalkylene glycols such as polypropylene glycol, powders such as coloring agents and pigments, dyes, surfactants, plasticizers, tackifiers, surface lubricants, leveling agents, An antioxidant, an antioxidant, a light stabilizer, an ultraviolet absorber, a polymerization inhibitor, an inorganic or organic filler, a metal powder, a particulate form, a foil, or the like. Also, within the controllable range, a redox type additive to which a reducing agent is added may be used.

< The adhesive layer Formation and The adhesive layer Application example >

An adhesive layer can be formed on various optical films using the adhesive composition in the above-described specific embodiments. The optical film having such a pressure-sensitive adhesive layer is also referred to as a pressure-sensitive adhesive optical film. The method of forming the pressure-sensitive adhesive layer includes, for example, a method of applying the pressure-sensitive adhesive composition to a separator (first separator) treated with a mold release agent, drying and removing a polymerization solvent to form a pressure-sensitive adhesive layer, Or a method of applying the pressure-sensitive adhesive composition to an optical film and drying and removing the polymerization solvent to form an adhesive layer on the optical film; And so on. At the time of applying the pressure-sensitive adhesive composition, at least one solvent other than the polymerization solvent may be newly added.

As the separator, for example, a silicon liner can be specifically used. Such a liner may, for example, be a silicone-based release agent treated on one side of the liner. Such a silicone-based releasing agent can facilitate the transfer of the pressure-sensitive adhesive composition formed on the separator to the optical film.

A specific method of forming an adhesive layer may include a method of forming a coating film by applying a pressure-sensitive adhesive composition onto a separator or an optical film. And a method of heating and drying the coating film after formation of the coating film. The heating and drying temperature may be 40 占 폚 to 200 占 폚, specifically, 50 占 폚 to 180 占 폚, and more specifically, 70 占 폚 to 170 占 폚. By setting the heating temperature within the above range, a pressure-sensitive adhesive composition having excellent pressure-sensitive adhesive properties can be obtained.

The drying time can be appropriately and appropriately employed. The drying time may be specifically 5 seconds to 20 minutes, more specifically 5 seconds to 10 minutes, particularly 10 seconds to 5 minutes.

In one embodiment, when the pressure-sensitive adhesive composition is applied to the surface of the optical film, after an anchor layer is formed on the surface of the optical film, various kinds of easy adhesion treatment such as formation treatment, corona treatment and plasma treatment are performed, )can do. In addition, an easy adhesion treatment may be performed on the surface of the adhesive layer.

The method of applying the pressure-sensitive adhesive composition is not particularly limited, and examples thereof include a roll coating, a kiss roll coating, a gravure coating, a reverse coating, a roll brush, a spray coating, a dip coating, a bar coating, a knife coating, An extrusion coating method using a lip coat, a die coat and the like.

A crosslinking treatment can be carried out when the adhesive layer is formed. Such a crosslinking treatment may be carried out at a temperature in the drying step of the adhesive layer, or may be carried out by providing a separate crosslinking step after the drying step. The above-mentioned crosslinking treatment can fully take account of the influence of the crosslinking treatment temperature and the crosslinking treatment time, as well as adjusting the addition amount of the whole crosslinking agent.

Specifically, the crosslinking treatment temperature, the crosslinking treatment time and the like can be adjusted according to the crosslinking agent to be used. In one embodiment, the crosslinking treatment temperature during formation of the pressure-sensitive adhesive composition may be 170 占 폚 or less, specifically 130 占 폚 or less. The energy efficiency can be improved when the adhesive layer is formed in the above range. Further, when a specific separator (for example, PET) is used as a substrate for forming an adhesive layer, there is an advantage that foreign substances such as oligomers can be inhibited from being produced. The foreign substance (for example, oligomer) may be produced at 30 ppm or less, specifically 10 ppm or less. And is suitable for use as an adhesive for an optical film in the above-mentioned range.

The crosslinking treatment time can be set in consideration of productivity and workability. In one embodiment, the crosslinking treatment time in the formation of the pressure-sensitive adhesive composition may be from 0.2 minute to 20 minutes, from 0.5 to 10 minutes.

In one embodiment, a peroxide crosslinking treatment may be performed with a peroxide-based crosslinking agent during the crosslinking treatment to form an adhesive layer.

The pressure-sensitive adhesive layer is an adhesive layer formed by a crosslinking treatment of a pressure-sensitive adhesive composition comprising a pressure-sensitive adhesive resin comprising at least one of a (meth) acrylic polymer, a urethane polymer and a polyester, a silicate oligomer represented by the following formula (1) At a temperature of 23 占 폚 and a humidity of 65% RH, the gel fraction according to the following formula 1 may be 40 wt% to 95 wt% after being left for 1 hour from the formation of the adhesive layer.

[Chemical Formula 1]

[Formula 1]

Gel fraction (% by weight) = {(Wc-Wa) / (Wb-Wa)} 100

When the pressure-sensitive adhesive composition forms a pressure-sensitive adhesive layer by peroxide crosslinking treatment, the gel fraction after 1 hour can be in the range of 40 wt% to 95 wt%, specifically 65 wt% to 95 wt%. In the above-mentioned range, the pressure-sensitive adhesive layer is free from the risk of pressure drop and durability deterioration, and does not require aging, and thus has excellent workability.

The peroxide cross-linking treatment time may be at least the half-life time corresponding to the peroxide cross-linking treatment temperature (170 占 폚 or lower, specifically 130 占 폚 or lower) peroxide crosslinking treatment.

The adhesive resin preferably has an acid value of from 0 mgKOH / g to 20.0 mgKOH / g, specifically from 0 mgKOH / g to 10.0 mgKOH / g, more specifically from 0 mgKOH / g to 5.0 mgKOH / g, To 0 mgKOH / g to 3.0 mgKOH / g. In the above-mentioned range, the pressure-sensitive adhesive composition is excellent in adhesion and reliability and can balance the rework performance.

Since the composition includes a peroxide-based crosslinking agent, the adhesive layer can be formed by a peroxide crosslinking treatment.

The peroxide cross-linking treatment can be decomposed by 50 wt% or more of the peroxide-based cross-linking agent. Based crosslinking agent to decompose at least 50% by weight of the peroxide-based crosslinking agent, whereby the gel fraction of the pressure-sensitive adhesive layer can be made 40% by weight to 95% by weight.

The difference between the initial adhesive force and the adhesive force after heating may be 1 N / 25 mm or less in the adhesive layer. The reworkability and reliability of the adhesive layer are excellent in the above range.

The initial adhesive force is an adhesive force to an initial glass plate, and the adhesive force after heating is an adhesive force to a glass plate after heating. The initial glass plate and the glass plate after heating are manufactured as follows.

The adhesive polarizing film (sample) was cut into a width of 25 mm and a length of 100 mm, and the plate was attached to a non-alkali glass plate (Eagle XG, product of Corning Incorporated) having a thickness of 0.5 mm using a laminator. Then, the glass plate with the polarizing film is autoclaved at 50 DEG C and 5 atm for 15 minutes to completely adhere the polarizing film to the alkali-free glass. Thus, an initial glass plate is produced. Then, the initial glass plate is heated at 50 캜 for 48 hours under drying conditions, and a glass plate is produced after heating. Then, the adhesion between the initial glass plate and the glass plate after heating is measured by the following method.

The adhesive force (N / 25 mm) at the time of peeling the polarizing film from each glass plate is measured using a tensile tester (Tensoron Universal Material Tester STA-1150 manufactured by Orientech). The measurement conditions are 23 占 폚, relative humidity 50%, peeling angle 180 占 and peeling speed 300 mm / min. The removal is performed by the method of testing the adhesive tape and the pressure-sensitive adhesive sheet of JIS Z0237.

The adhesive layer may have an adhesive force of 3 N / 25 mm or less, specifically 2.5 N / 25 mm or less after heating. The reworkability and reliability of the adhesive layer are excellent in the above range.

The thickness of the adhesive layer is not particularly limited, but may be, for example, 1 m to 100 m. Specifically, it is from 2 탆 to 50 탆, more specifically from 2 탆 to 40 탆, and more specifically from 5 탆 to 35 탆. Within the above range, the adhesion of the adhesive layer and the releasability can be effectively achieved.

When the surface of the adhesive layer is to be exposed during storage, a release agent-treated separator (second separator) may be additionally formed to protect the adhesive layer. Such a second separator is used when the adhesive layer is applied.

&Lt; Adhesive type optical film &

The adhesive optical film of the present invention may include an optical film and the adhesive layer formed on one side or both sides of the optical film.

As the optical film, those used for forming an image display device such as a liquid crystal display device are used, and the kind thereof is not particularly limited. For example, the optical film may include a polarizer. Specifically, the adhesive optical film may include a polarizer, a protective layer formed on one side of the polarizer, and an adhesive layer formed on the other side of the polarizer, and the adhesive layer may be formed of the adhesive composition for an optical film.

The polarizer may have a transparent protective film on at least one side of the polarizer. The polarizer is not particularly limited. For example, a polarizer may be added to a hydrophilic polymer film such as a polyvinyl alcohol film, a partially foamed polyvinyl alcohol film, and an ethylene / vinyl acetate copolymerization system partially saponified film, A material obtained by uniaxially stretching by adsorbing a substance, a polyene-based oriented film such as a dehydrated product of polyvinyl alcohol, a dehydrochlorinated product of polyvinyl chloride, and the like. In a specific example, a polarizer comprising a polyvinyl alcohol-based film and a dichroic substance such as iodine can be used as the polarizer. In this case, the optical characteristics and handling property of the polarizing film can be more excellent. The thickness of the polarizer is not particularly limited, but may be, for example, 5 탆 to 80 탆.

The protective layer is not limited as long as it can protect the polarizer. Specifically, the protective layer may be a transparent protective film. The transparent protective film may be bonded to one or both sides of the polarizer by an adhesive layer. For the adhesion treatment of the polarizer and the transparent protective film, an adhesive is used. Examples of the adhesive include an isocyanate-based adhesive, a polyvinyl alcohol-based adhesive, a gelatin-based adhesive, a vinyl-based latex-based, water-based polyester, and the like. The adhesive is usually used as an adhesive composed of an aqueous solution, and may contain, for example, from 0.5% by weight to 60% by weight of solids. In addition to the above, examples of the adhesive for the polarizer and the transparent protective film include an ultraviolet curable adhesive, an electron beam curable adhesive, and the like. The adhesive for an electron beam curing type polarizing film exhibits suitable adhesiveness to the above various transparent protective films. The adhesive for bonding the polarizer and transparent protective film of one specific example may further contain a metal compound filler.

As a material constituting the transparent protective film, for example, a thermoplastic resin excellent in transparency, mechanical strength, thermal stability, moisture barrier property, isotropy and the like is used. Specific examples of such a thermoplastic resin include cellulose resins such as triacetyl cellulose, polyester resins, polyether sulfone resins, polysulfone resins, polycarbonate resins, polyamide resins, polyimide resins, polyolefin resins, (meth) acrylic resins , Cyclic polyolefin resins (norbornene resins), polyarylate resins, polystyrene resins, polyvinyl alcohol resins, and mixtures thereof. On one side of the polarizer, a transparent protective film is bonded by an adhesive layer, and on the other side, a thermosetting resin such as a (meth) acrylic resin, a urethane resin, an acrylic urethane resin, an epoxy resin, Resin can be used. The transparent protective film may contain one or more optional additives. Examples of the additive include an ultraviolet absorber, an antioxidant, a lubricant, a plasticizer, a release agent, a coloring inhibitor, a flame retardant, a nucleating agent, an antistatic agent, a pigment and a colorant. Specifically, the content of the thermoplastic resin in the transparent protective film is 50 to 100% by weight, more specifically 50 to 99% by weight, more specifically 60 to 98% by weight, particularly preferably 70 to 97% by weight . When the content of the thermoplastic resin in the transparent protective film is 50% by weight or less, there is a fear that the transparency and the like inherently possessed by the thermoplastic resin can not be sufficiently manifested.

Though the thickness of the transparent protective film can be appropriately determined, it is generally about 1 to 500 占 퐉 in view of workability such as strength and handling properties and thin layer properties. Especially from 1 탆 to 300 탆, and from 5 탆 to 200 탆. Particularly, the pressure-sensitive adhesive layer of one embodiment is suitable for forming a pressure-sensitive adhesive layer directly on a thin transparent protective film having a thickness of 40 占 퐉 or less.

In other embodiments, the protective layer may be a protective coating layer. The protective coating layer may be formed of an active energy ray-curable resin composition comprising an active energy ray-curable compound and an initiator. The active energy ray-curable compound may include at least one of an acrylic compound, an epoxy compound, and an isocyanurate compound.

The protective coating layer may have a thickness of 5 탆 to 200 탆, specifically 5 탆 to 20 탆, more specifically 4 탆 to 10 탆. Within this range, the protective coating layer can be formed directly on the polarizer without use of an adhesive, and the polarizing plate can be thinned.

Further, the adhesive optical film can be laminated with another optical film. As another optical film, for example, a liquid crystal display device such as a reflection plate or a transflective plate, a retardation film (including a wave plate of 1/2 or 1/4), a time compensation film, And the like can be used as the optical layer. These polarizing films may be laminated on the polarizing film for practical use, or one or two or more layers may be used. For example, the adhesive optical film may further include a retardation film formed on the adhesive layer.

The optical film obtained by laminating the above optical layers on the adhesive optical film can be formed by sequentially laminating them separately in the course of production of a liquid crystal display device or the like. It is advantageous that the manufacturing process of the liquid crystal display device and the like can be improved. Appropriate adhesion means such as an adhesive layer can be used for the lamination. When the polarizing film and another optical layer are bonded to each other, their optical axes can be set at appropriate arrangement angles in accordance with the intended retardation characteristics and the like.

A polarizer obtained by dying a polyvinyl alcohol film with iodine and uniaxially stretching can be prepared by, for example, dying polyvinyl alcohol in an aqueous solution of iodine and stretching it to 3 to 7 times the original length. If necessary, may be immersed in an aqueous solution of potassium iodide or the like which may contain boric acid, zinc sulfate, zinc chloride or the like. If necessary, the polyvinyl alcohol film may be dipped in water and washed with water before dyeing. The polyvinyl alcohol film can be cleaned by rinsing the surface of the polyvinyl alcohol film with water and swelling the polyvinyl alcohol film to prevent unevenness such as uneven dyeing. Stretching may be performed after dyeing with iodine, stretching while dyeing, or dyeing with iodine after stretching. It can be stretched in an aqueous solution such as boric acid or potassium iodide or in a water bath.

Examples of the optical film include a liquid crystal display (liquid crystal display) such as a reflection plate or a transflective plate, a retardation film (including a wave plate of 1/2 or 1/4), a time compensation film, a luminance enhancement film, And an optical layer that can be used for forming an optical disc, an apparatus, and the like. In addition to being usable as an optical film alone, they can be laminated to the polarizing film at the time of practical use and used in one layer or two or more layers. For example, the optical film and the adhesive optical film including the adhesive layer may further include a retardation film formed on the adhesive layer.

The thicknesses of the various optical films listed above are not particularly limited, but the pressure-sensitive adhesive composition according to one embodiment is capable of ensuring reworkability of the optical film even when the optical film is thin (for example, 100 탆 or less) And has high reliability. An adhesive layer may be formed on the optical film, and an adhesive layer may be formed on the adhesive layer. The adhesion-assisting layer is a layer having wettability with respect to the adhesive layer or the like, which is larger than that of the optical film. The adhesion-assisting layer is produced, for example, by corona-treating an optical film. An adhesion-assisting layer may be separately prepared and then adhered to the optical film. Specifically, the adhesion-assisting layer may be formed on at least one of the optical film surface and the adhesive layer surface. By forming the adhesion-assisting layer, the pressure-sensitive adhesive layer can be easily formed on the optical film.

Figs. 1 and 2 show examples of the adhesive optical film. The adhesive optical film 10 shown in Fig. 1 has an optical film 11 and an adhesive layer 12 formed on one side of the optical film 11. Fig. The adhesive layer 12 is formed on the optical film 11 by applying a solution of the pressure-sensitive adhesive composition on one surface of the optical film 11, for example, and then removing the solvent as described above. The optical film 11 may be, for example, a polarizer. As described above, the pressure-sensitive adhesive composition may be used as a pressure-sensitive adhesive layer previously formed on an optical film. The adhesive layer 12 may be formed on both surfaces of the optical film 11. Fig. 2 shows a modified example of the adhesive optical film 10. The adhesive optical film 10 shown in Fig. 2 has an adhesive auxiliary layer 11a formed between the optical film 11 and the adhesive layer 12. The adhesion-assisting layer 11a has a wettability and the like with respect to the adhesive layer 12 is larger than that of the optical film 11. [

The display device of the present invention may include the above-mentioned adhesive optical film. Examples of the display device include a liquid crystal display device, an organic electroluminescence display device, and the like.

Fig. 3 and Fig. 4 show a configuration example of a display device having an adhesive layer according to one embodiment. The display device 20 shown in Fig. 3 includes a display element 21, an adhesive layer 22, and an optical film 23. The optical film 23 is disposed on both surfaces of the display element 21 and the adhesive layer 22 bonds the display element 21 and the optical film 23 together. The display device 20 may be manufactured by attaching an adhesive optical film comprising the adhesive layer 22 and the optical film 23 to both surfaces of the display element 21. [ The adhesive layer 22 may be formed on both surfaces of the display element 21 and the optical film 23 may be attached to the adhesive layer 22.

Fig. 4 shows a modification of the display device 20. Fig. As shown in Fig. 4, a plurality of optical films may be provided on the display element 21. Fig. In the display device 20 shown in Fig. 4, an adhesive layer 24 and an optical film 25 are further provided on the optical film 23 of the display device 20 shown in Fig. The adhesive layer 24 and the optical film 25 are provided on the optical film 23 in the same manner as the adhesive layer 22 and the optical film 23.

The display device 20 may be, for example, a liquid crystal display device, an organic EL display device, or the like as described above. When the display device 20 is a liquid crystal display device, the display element 21 becomes a liquid crystal cell and the optical film 23 becomes a polarizing film. The optical film 25 may be, for example, a viewing angle increasing film, a luminance improving film, various protective films, and the like. When the display device 20 is a liquid crystal display device, a retardation plate may be disposed between the adhesive layer 22 and the display element 21. [ The retardation plate and the display element 21 may be bonded by an adhesive layer. Although the thickness of the display element 21 is not particularly limited, the pressure-sensitive adhesive composition according to one embodiment may be applied to the display element 21 even if the display element 21 is thin (for example, 200 m or less) While ensuring workability, has high reliability. In other words, the pressure-sensitive adhesive composition according to one embodiment has high reliability while securing reworkability for either or both of the optical film and the display element.

< Adhesive layer Manufacturing method>

The method for producing an adhesive layer according to the present invention comprises the steps of forming an adhesive layer on one side or both sides of a substrate with a pressure sensitive adhesive composition for an optical film, wherein the pressure sensitive adhesive composition for an optical film has an acid value of from 0 mgKOH / g to 20.0 mgKOH / A resin and a silicate oligomer represented by the following formula (1).

[Chemical Formula 1]

Wherein R ₁ to R ₄ are each independently hydrogen, an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, X ₁ and X ₂ each independently represent hydrogen, An alkyl group or an aryl group having 6 to 20 carbon atoms, and n is an integer of 1 to 100. Specifically, each of R ₁ to R ₄ independently represents an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 12 carbon atoms, X ₁ and X ₂ each independently represent hydrogen, an alkyl group having 1 to 6 carbon atoms, 12 < / RTI > For example, R ₁ to R ₄ may be a methyl group, an ethyl group, or a phenyl group.

The substrate may be an optical film. As the optical film, those used for forming an image display device such as a liquid crystal display device are used, and the kind thereof is not particularly limited. The optical film is substantially the same as that described in the adhesive layer. For example, the optical film may be a polarizing film.

The step of forming the pressure-sensitive adhesive layer may include a step of forming a layer containing a pressure-sensitive adhesive composition for an optical film on one side or both sides of the substrate, and a step of peroxide-crosslinking the layer containing the pressure-sensitive adhesive composition for the optical film.

A peroxide cross-linking treatment can be performed in the production of the adhesive layer. The cross-linking treatment is substantially the same as described in the adhesive layer formation process. Specifically, the peroxide cross-linking treatment can be performed at 130 ° C or lower, wherein the peroxide crosslinking agent can be decomposed by 50 wt% or more, And the fraction may be 40 wt% to 95 wt%.

In one embodiment, the pressure-sensitive adhesive composition for an optical film contains 0.01 to 2 parts by weight peroxide-based crosslinking agent per 100 parts by weight of the adhesive resin, 0.02 to 2 parts by weight, 0.04 to 1.5 parts by weight, 0.05 By weight to 1 part by weight.

In another embodiment, the pressure-sensitive adhesive composition for an optical film may contain 0.01 to 50 parts by weight, specifically 0.5 to 20 parts by weight, more specifically 0.5 to 10 parts by weight, of the silicate oligomer relative to 100 parts by weight of the pressure- And more specifically from 1 part by weight to 5 parts by weight. Within the above range, the initial reworkability and adhesive force after heating of the pressure-sensitive adhesive composition can be further improved.

In another embodiment, the pressure-sensitive adhesive composition for an optical film may further comprise a crosslinking agent. Examples of the crosslinking agent include isocyanate crosslinking agents, carbodiimide crosslinking agents, oxazoline crosslinking agents, peroxide crosslinking agents, epoxy crosslinking agents, and imine crosslinking agents.

[ Example ]

Next, an embodiment of a concrete example will be described. In the following examples, the concentration of the solution is expressed as% by weight based on the total weight of the solution.

<A. Re-workability And for reliability assessment Example >

The following Examples and Comparative Examples were carried out to evaluate the workability and reliability of the adhesive layer.

Manufacturing example 1 (of acrylic resin Manufacturing example )

An acrylic resin (polymer A1), which is an example of a sticky resin, was produced by the following steps. A four-necked flask equipped with a stirrer, a thermometer, a nitrogen gas introducing tube, and a condenser was charged with 99 parts by weight of butyl acrylate, 1 part by weight of 4-hydroxybutyl acrylate, 2,2'-azobisisobutyronitrile 0.15 part by weight of nitrile was added together with 100 parts by weight of ethyl acetate. Then, while the mixed solution was gently stirred, nitrogen gas was introduced into the four-necked flask to replace with nitrogen. Thereafter, the liquid temperature in the flask was maintained at around 55 캜, and the monomers were allowed to undergo a polymerization reaction for 5 hours. As a result, a solution of the polymer A1 was prepared. The weight average molecular weight (Mw) of the polymer A1 was 2.1 million. The acid value of the polymer A1 was 0 mgKOH / g. Table 1 shows the composition of the polymer A1 (the weight ratio of the monomer constituting the polymer A1), the weight average molecular weight and the acid value.

Here, the weight average molecular weight of the polymer A1 was measured by GPC (gel permeation chromatography). The measuring device and measurement conditions are as follows.

Analyzer: Toso product, HLC-8120GPC

Column: Toso products, G7000HXL + GMHXL + GMHXL

Column size: Each 7.8 mmφ × 30 cm Total 90 cm

Column temperature: 40 DEG C

Flow rate: 0.8 ml / min

Injection amount: 100 μl

Eluent: Tetrahydrofuran

Detector: Differential refractometer (RI)

Standard sample: Polystyrene

The acid value of the polymer A1 was measured by the following process. A mixed solvent containing toluene, isopropyl alcohol and distilled water at a weight ratio of 50: 49.5: 0.5 was prepared. Next, about 0.5 g (based on solid content) of polymer A1 was precisely weighed and dissolved in 50 g of the mixed solvent. Thus, a sample solution for titration was prepared. This sample solution was subjected to neutralization titration with a 0.1 KOH aqueous solution using a titration apparatus "COMTITE-550" manufactured by HIRANUMA. The acid value of the polymer A1 was calculated from the obtained results and the following [formula 2].

[Formula 2]

Acid value [mgKOH / g] = (a-b) x 5.611 x F / S

In Equation 2,

a: Amount of aqueous KOH solution required for titration of the sample solution [ml]

b: Amount of KOH aqueous solution [ml] required for titration of the blank (mixed solvent)

F: Potency of aqueous KOH solution

S: Weight of resin contained in the sample solution supplied to titration [g]

to be.

Manufacturing example 2 to 7 (of acrylic resin Manufacturing example )

Polymers A2 to A6 were prepared by carrying out the same processes as in Production Example 1 except that the kinds and the weight ratios of the monomers charged into the four-necked flask were changed as shown in Table 1. The weight average molecular weight and acid value of the polymers A2 to A7 were measured by the same method as in Production Example 1. [ The results are summarized in Table 1.

Manufacturing example 8 (urethane resin Manufacturing example )

A urethane resin (polymer A8) was produced by the following steps. To a four-necked flask equipped with a stirrer, a reflux condenser, a nitrogen inlet tube, a thermometer and a dropping funnel was charged 51.9 g of a polyester polyol P-1010 (bifunctional polyester polyol, OH: 112 mg / g, manufactured by Kuraray Co., 32.2 g of Adeka polyether G-1500 (trifunctional polyether poly, trifunctional, OH of 109 mg / g, manufactured by ADEKA KK), 15.8 g of isophorone diisocyanate (IPDI) (Sumitomo Bayer Co., Ltd.) , 66.7 g of toluene, 0.03 g of 2-ethylhexanoate as a catalyst, and 0.04 g of lead naphthenate.

Next, the mixed solution was gradually heated to 90 DEG C, and the monomers were subjected to polymerization reaction for 4 hours. The residual isocyanate group was confirmed by an infrared spectrophotometer (IR), the reaction was terminated at the timing when the peak corresponding to the isocyanate group disappeared, and the mixed solution after the reaction, that is, the solution of the urethane resin was cooled. The urethane resin solution was colorless transparent and had a solid content of 60% by weight. The weight average molecular weight and the acid value were measured in the same manner as in Production Example 1, and found to have a weight average molecular weight of 50,000 and an acid value of 0.5 KOH mg / g. The composition of the polymer A8 (weight ratio of the monomer constituting the polymer A8), the weight average molecular weight and the acid value are shown in Table 2.

Manufacturing example 9 (of polyester resin Manufacturing example )

A polyester resin (polymer A9) was produced by the following steps. A four-necked separable flask equipped with a thermometer, a stirrer, a distillation tube and a condenser was charged with 11.7 g of ethylene glycol, 18.6 g of neopentyl glycol, 11.8 g of isophthalic acid, 57.9 g of sebacic acid, Was added. Thereafter, the esterification reaction was carried out by heating the mixed solution at 150 to 270 캜 for 150 minutes. Subsequently, the pressure of the reaction system was gradually lowered to 133 Pa after 30 minutes, and the reaction was continued for 180 minutes while the reduced pressure was continued. Next, the mixed solution after the reaction was diluted with ethyl acetate to obtain a solution of the polyester resin. The solid content of this solution was 60% by weight. The weight average molecular weight and acid value of the polyester resin were measured by the same method as in Production Example 1. The weight average molecular weight was 38,000 and the acid value was 0.3 KOH mg / g. The composition of the polymer A9 (weight ratio of the monomer constituting the polymer A8), weight average molecular weight and acid value are shown in Table 3.

Manufacturing example Polymer Type of polymer BA 2HEA 4HBA AA Molecular weight (Mw) Acid value
(mgKOH / g) One A1 acryl 99 - One - 2.1 million 0 2 A2 acryl 99 0.1 - 0.9 2.1 million 7 3 A3 acryl 96.6 - One 2.4 2.1 million 18.7 4 A4 acryl 95 - - 5 2.1 million 38.9 5 A5 acryl 96 - One 3 2.1 million 23.4 6 A6 acryl 99 - - One 2.1 million 7.8 7 A7 acryl 99 - One - 80 million 0 BA: butyl acrylate, 2HEA: 2-hydroxyethyl acrylate,
4HBA: 4-hydroxybutyl acrylate, AA: acrylic acid

Manufacturing example Polymer Type of polymer P-1010 G-1500 IPDI Molecular weight (Mw) Acid value
(mgKOH / g) 8 A8 urethane 51.9 32.2 15.9 5.0 million 0.5 P-1010: polyester polyol, G-1500: adeka polyether
IPDI: Isophorone di-iso-cyanate

Manufacturing example Polymer Type of polymer EG NPG IPA SA Molecular weight (Mw) Acid value
(mgKOH / g) 9 A9 Polyester 11.7 18.6 11.8 57.9 3.8 million 0.3 EG: ethylene glycol, NPG: neopentyl glycol
IPA: isophthalic acid, SA: Sebastian

The ingredients in Tables 1 to 3 are expressed in parts by weight.

Manufacturing example 10 (high molecular weight type Manufacturing example )

A silicate oligomer B1 of high molecular weight type was prepared by the following steps. 152 g (1 mole, 4 equivalents) of tetramethoxysilane was dissolved in 500 g of tetrahydrofuran (hereinafter also referred to as " THF "). Next, 72 g (8 equivalents) of 0.35 wt% hydrochloric acid aqueous solution was added to the obtained solution and mixed. Then, the mixed solution was allowed to stand at 20 占 폚 for 1 hour to hydrolyze tetramethoxysilane. Then, 450 g of polymethoxysiloxane ("MKC Silicate MS-51" manufactured by Mitsubishi Chemical Corporation) was added to the hydrolyzed solution, that is, the reaction solution, and reflux was carried out for 2 hours. Thereafter, the temperature of the reaction solution was increased to 150 DEG C to distill THF. As a result, a silicate oligomer B1 in the form of a colorless and transparent liquid was obtained. The silicate oligomer B1 had a weight average molecular weight of 25,000. The starting material, polymethoxysiloxane (" MKC Silicate MS-51 "), is an oligomer having a weight average molecular weight of 900. Thus, the hydrolyzed tetramethoxysilane and the polymethoxysiloxane were bonded to each other to produce a high molecular weight silicate oligomer. And R ₁ to R ₄ , X ₁ and X ₂ of the silicate oligomer B1 are all methyl groups.

The weight average molecular weight of the silicate oligomer B1 was measured by GPC (gel permeation chromatography).

The measuring device and measurement conditions are as follows.

Analyzer: Toso product, HLC-8120GPC

Column: TSKgel, SuperHZM-H / HZ4000 / HZ2000

Column size: 6.0 mm (inner diameter) x 150 mm

Column temperature: 40 DEG C

Flow rate: 0.6 ml / min

Injection amount: 20 μl

Eluent: Tetrahydrofuran

Detector: Differential refractometer (RI)

Standard sample: Polystyrene

Manufacturing example 11 ( Phenoxy Type Manufacturing example )

A silicate oligomer B2 in which R ₁ to R ₄ , X ₁ and X ₂ in the general formula (1) are a phenyl group or a methyl group (R ₁ to R ₄ , X ₁ or X ₂ is a phenyl group) is prepared by the following steps. 400 g (1 mole, 4 equivalents) of tetraphenoxysilane was dissolved in 500 g of THF. Next, 72 g (8 equivalents) of 0.35 wt% hydrochloric acid aqueous solution was added to the obtained solution and mixed. Then, the mixed solution was allowed to stand at 20 占 폚 for 1 hour to hydrolyze tetraphenoxysilane. Then, 450 g of polymethoxysiloxane ("MKC Silicate MS-51" manufactured by Mitsubishi Chemical Corporation) was added to the solution after the hydrolysis, that is, the reaction solution, and reflux was carried out for 2 hours. Thereafter, the temperature of the reaction solution was increased to 150 DEG C to distill THF. As a result, a silicate oligomer B2 in the form of a colorless transparent liquid was obtained. The weight average molecular weight of the silicate oligomer B2 was measured in the same manner as in Production Example 10, and the weight average molecular weight of the silicate oligomer B2 was 5,000. Polymethoxysiloxane (" MKC Silicate MS-51 ") as a raw material is an oligomer having a molecular weight of 900. Thus, the hydrolyzed tetraphenoxysilane and the polymethoxysiloxane are bonded to each other to produce a silicate oligomer B2 in which R ₁ to R ₄ , X ₁ and X ₂ are a phenyl group or a methyl group.

In addition, the present inventors obtained several silicate oligomers in addition to the above, and provided them in the following respective experiments.

Of optical film Manufacturing example

Manufacturing example 12 ( Protection Polarizing film)

A polarized protective polarizing film was produced as an optical film by the following steps. A polyvinyl alcohol film having a thickness of 20 占 퐉 was stretched to 3 times while dyeing in a 0.3% by weight iodine solution at 30 占 폚 for 1 minute between rolls having different speed ratios. Thereafter, the stretched film was immersed in an aqueous solution containing boric acid at 4% by weight and boric acid at 4% by weight and potassium iodide at 60 캜 for 0.5 minutes, and the stretched film was stretched to a total stretching magnification of 6 times. Next, the stretched film was washed by immersing in an aqueous solution containing potassium iodide at 30 DEG C and 1.5 wt% of potassium iodide for 10 seconds, followed by drying at 50 DEG C for 4 minutes. Thus, a polarizer was obtained. Then, an acrylic film (lactone-modified acrylic resin film) having a thickness of 20 占 퐉 was bonded to one side of the polarizer with a polyvinyl alcohol-based adhesive. The acrylic film is an example of a protective film. As a result, a protective polarizing film having a total thickness of 27 탆 was produced.

< Example 1>

Production of pressure-sensitive adhesive composition

5 parts by weight of methyl silicate 51 (weight average molecular weight: 550) manufactured by COLCOAT CO. LTD., 5 parts by weight of an isocyanate-based crosslinking agent, Takenate D110N (A 75 wt% ethyl acetate solution of trimethylolpropane adduct of xylylene diisocyanate, the number of isocyanate groups in one molecule: 3, manufactured by Mitsui Chemicals Co., Ltd.), and 0.1 part by weight of a silane coupling agent (trade name: KBM-403, Shinetsu Kagaku Co., Product, 3-glycidoxypropyltrimethoxysilane) were added. Thus, a pressure-sensitive adhesive composition solution (solid content 15% by weight) was obtained. The composition of the pressure-sensitive adhesive composition is shown in Table 4.

Production of adhesive polarizing film (adhesive optical film)

The pressure-sensitive adhesive composition solution was applied onto one surface of a 38 탆 -thick polyethylene terephthalate (PET) film (product of Mitsubishi Chemical Corporation, MRF38, without oligomer-preventing layer) subjected to silicone treatment and the thickness of the pressure- Mu] m. Next, the coated layer was dried at 100 캜 for 2 minutes to form a pressure-sensitive adhesive layer. An adhesive polarizing film was produced by adhering an adhesive layer to a polarizing plane (corona-treated plane) subjected to corona treatment at a corona discharging amount of 80 [W · min / m 2] on the polarizing polarizing film produced in Production Example 12 Respectively.

Example 2 to 22, Comparative Example 1 to 8

A pressure-sensitive polarizing film was produced in the same manner as in Example 1 except that the composition of the pressure-sensitive adhesive resin was changed to the composition shown in Table 4.

In Table 4, silicate oligomer B3 is methyl silicate 51 in which all of R ₁ to R ₄ , X ₁ and X ₂ are methyl groups and the weight average molecular weight is 600. Silicate oligomer B4 is methyl silicate 53A (manufactured by Colcoat Co., Ltd.) in which all of R ₁ to R ₄ , X ₁ and X ₂ are methyl groups and the weight average molecular weight is 900. Silicate oligomer B5 is MKC silicate MS58B15 (manufactured by Mitsubishi Chemical Corp.) in which R ₁ to R ₄ , X ₁ and X ₂ are butyl groups (15%) and the remainder are methyl groups (85%) and the weight average molecular weight is 3,200 . Silicate oligomer B6 is EMS-485 (manufactured by Colcoat Co., Ltd.) having R ₁ to R ₄ , X ₁ and X _{2 each} having a methyl group (50%) and an ethyl group (50%) and a weight average molecular weight of 1,300. Silicate oligomer B7 is an ethyl silicate 48 (manufactured by Colcoat Co., Ltd.) in which all of R ₁ to R ₄ , X ₁ and X ₂ are an ethyl group and a weight average molecular weight is 1,400.

PEROYL TCP is a peroxide type crosslinking agent manufactured by NOF CORPORATION.

&Lt; Property evaluation method &

(1) Reliability evaluation test

A reliability evaluation test was conducted on the adhesive polarizing films (adhesive optical films) according to each of the examples and the comparative examples. Specifically, an adhesive polarizing film (sample) was cut into a 37-inch size (length 56.4 cm × width 75.2 cm size), and a 0.5 mm thick alkali-free glass (Eagle XG manufactured by Corning Incorporated) (laminating machine). Further, the alkali-free glass is used as a liquid crystal cell glass substrate. In actual liquid crystal cells, two pieces of alkali-free glass having a thickness of 0.25 mm are used. Then, in this test and a later-described adhesive force and reworkability evaluation test, the adhesive polarizing film is affixed to both sides of the alkali-free glass. Therefore, excellent properties of these means that the adhesive polarizing film can be suitably used as a polarizing film of a liquid crystal cell.

Subsequently, the glass plate with the polarizing film was subjected to autoclave treatment at 50 DEG C and 0.5 MPa for 15 minutes, whereby the sample was brought into close contact with the completely alkali-free glass. A glass plate with a polarizing film (hereinafter also referred to as " initial glass plate ") subjected to such treatment was kept at 85 캜 for 500 hours (heating test). Further, the initial glass plate was treated for 500 hours in an atmosphere of 60 DEG C / 95% RH (relative humidity) (humidification test). Further, the heat cycle in which the initial glass plate was held at 85 캜 for 30 minutes and at -40 캜 for 30 minutes was performed for 300 cycles (heat shock test). After each test, the appearance between the polarizing film and the glass was visually evaluated based on the following criteria. The evaluation results are shown in Table 5.

⊚: No change in appearance such as foaming, peeling, no lifting.

?: A little, but there is peeling or foaming at the end, but there is no practical problem.

?: There is peeling or foaming at the end, but there is no practical problem unless it is used for a special purpose.

X: Significant peeling at the end, causing a problem in practical use.

(2) adhesion and Re-workability Evaluation test

The adhesive polarizing films (adhesive optical films) according to each of the Examples and Comparative Examples were subjected to an adhesive force evaluation test. Specifically, the adhesive polarizing film (sample) was cut into a width of 25 mm and a length of 100 mm, and the plate was attached to a non-alkali glass plate (Eagle XG, product of Corning Incorporated) having a thickness of 0.5 mm using a laminator. Then, the glass plate with the polarizing film was subjected to autoclave treatment at 50 DEG C and 5 atm for 15 minutes to completely adhere the polarizing film to the alkali-free glass. Thus, an initial glass plate was produced. Then, the initial glass plate was heated at 50 캜 for 48 hours under dry conditions. Thus, a glass plate was produced after heating. The adhesion between the initial glass plate and the glass plate after heating was measured by the following method.

That is, the adhesive force (N / 25 mm) at the time of peeling the polarizing film from each glass plate was measured using a tensile tester (Tensoron Universal Material Tester STA-1150 manufactured by Orientech). The measurement conditions were 23 deg. C, a relative humidity of 50%, a peeling angle of 180 deg., And a peeling rate of 300 mm / min. The peeling was carried out in accordance with the test method of the adhesive tape and the pressure-sensitive adhesive sheet of JIS Z0237.

Further, for the adhesive polarizing film (sample), a reworkability evaluation test was conducted. Specifically, first, the adhesive polarizing film (sample) was subjected to the same treatment as the adhesive force evaluation test to produce an initial glass plate and a glass plate after heating. However, the size of the adhesive polarizing film (sample) was 420 mm wide × 320 mm long. Thereafter, the polarizing film was peeled off from the initial glass plate and the heated glass plate by a human hand. Then, the same processing as described above was repeated three times. That is, three sheets of each of the initial glass sheet and the heated glass sheet were prepared, and the polarizing film was peeled from each glass sheet. The reworkability (actual recyclability) of each of the pressure-sensitive adhesive compositions was evaluated on the basis of the following criteria.

⊚: All three films are fully remained, and the polarizing film can be satisfactorily peeled without breaking. No breakage of alkali-free glass was observed.

&Amp; cir &: Some of the three films were peeled off due to peeling, though the film was broken. No breakage of alkali-free glass was observed.

?: The film was broken in all three sheets, but peeled off again by peeling. No breakage of alkali-free glass was observed.

X: All the remaining three films were peeled off or peeled several times, the film was broken and could not be peeled off. Further, the alkali-free glass may be broken.

responsibility Re-workability Heating test Humidification test Heat shock test Early
Adhesion
(N / 25 mm) Initial Actual Workability Adhesion after heating
(N / 25 mm) Actual reworkability after heating Example 1 ◎ ◎ ◎ 1.1 ◎ 1.9 ○ Example 2 ◎ ◎ ◎ 0.5 ◎ 0.8 ◎ Example 3 ○ ○ ○ 1.6 ◎ 2.5 ○ Example 4 ○ ○ ○ 0.2 ◎ 0.4 ○ Example 5 ◎ ◎ ◎ 1.9 ○ 2.8 ○ Example 6 ◎ ◎ ◎ 2.3 ○ 2.9 △ Example 7 ◎ ◎ ◎ 0.4 ◎ One ◎ Example 8 ◎ ◎ ◎ 0.5 ◎ 0.8 ◎ Example 9 ◎ ◎ ◎ 0.6 ◎ One ◎ Example 10 ◎ ◎ ◎ 1.2 ◎ 2.2 ○ Example 11 ◎ ◎ ◎ 0.3 ◎ 0.9 ◎ Example 12 ◎ ◎ ◎ 0.5 ◎ 1.3 ◎ Example 13 ◎ ◎ ◎ 0.4 ◎ 0.9 ◎ Example 14 ◎ ◎ ◎ 1.3 ◎ 2 ○ Example 15 ◎ ○ ◎ One ◎ 1.5 ◎ Example 16 ◎ ○ ◎ 0.8 ◎ 1.3 ◎ Example 17 ◎ ○ ◎ 0.7 ◎ 1.2 ◎ Example 18 ◎ ◎ ◎ 2.6 ○ 3.5 △ Example 19 ◎ ○ ◎ 2.2 ○ 2.7 ○ Example 20 ◎ ○ ◎ 0.9 ◎ 1.2 ◎ Example 21 ◎ ○ ◎ 1.2 ◎ 1.8 ◎ Example 22 ○ ○ ○ 0.5 ◎ 0.8 ◎ Comparative Example 1 ○ ○ ○ 3 △ 6.5 × Comparative Example 2 ◎ ◎ ◎ 4.5 × 9.2 × Comparative Example 3 ◎ ◎ ◎ 5.2 × 10.9 × Comparative Example 4 ○ ○ ○ 6.2 × 11.5 × Comparative Example 5 ◎ ◎ ◎ 3.6 △ 5.1 × Comparative Example 6 ◎ ○ ◎ 3.2 △ 4.5 × Comparative Example 7 ○ △ ○ 2.2 ○ 4.5 × Comparative Example 8 ○ △ ○ 3.5 △ 5.8 ×

As shown in Table 5, it was confirmed that the pressure-sensitive adhesive composition according to the present example is compatible with reworkability and reliability. In particular, the polarizing film and the non-alkali glass used in the evaluation test were all thin, but when the pressure-sensitive adhesive composition according to this example was used, the polarizing film and the alkali-free glass could be peeled off from the alkali-free glass with almost no breakage. According to Table 5, it can be seen that when the adhesive force exceeds 3 N / 25 mm, the reworkability tends to deteriorate.

<B. Re-workability , Reliability and workability Example >

The following Examples and Comparative Examples were carried out to evaluate the reworkability, reliability, and workability (whether the adhesive film needs aging) of the adhesive layer.

Silicate Oligomer

The silicate oligomers used in the Examples for A. workability and reliability evaluation with silicate oligomers were prepared. Specifically, the silicate oligomer B1 (Production Example 10), B2 (Production Example 11), methyl silicate 51 (silicate oligomer B3), methyl silicate 53A (silicate oligomer B4) MKC silicate MS58B15 (silicate oligomer B5), EMS-485 Silicate oligomer B6), and ethyl silicate 48 (silicate oligomer B7).

Peroxide crosslinking agent

(Perbutyl) ND (a half-life half-life temperature for one minute, 103.5 占 폚, in addition to peroyl TCP (one minute half-life temperature 92.1 占 폚) used in the examples for the A. riser workability and reliability evaluation as a peroxide cross- , And perbutyl PV (a half-life temperature for the first minute, 110.3 占 폚) were prepared.

Manufacture of optical film

A. An optical film (polarized protective polarizing film) used in Examples for reworkability and reliability evaluation was prepared.

Example 23 to 47 and Comparative Example 9 to 15

A pressure-sensitive polarizing film was produced in the same manner as in Example 1, except that the composition of the pressure-sensitive adhesive composition was changed to the composition shown in Table 6 and Table 7, and the drying temperature was changed to the temperature shown in Table 6. Specifically, the drying temperature was varied depending on the kind of the peroxide crosslinking agent. For example, in Example 23, peroyl TCP with a 1 minute half-life temperature of 92.1 ° C and a drying temperature of 120 ° C (2 minutes) were applied. By this drying treatment, at least 50% by weight of the peroxide-based crosslinking agent was decomposed.

Adhesive resin The silicate oligomer (B) Cross-linking agent Peroxide-based crosslinking agent Silane coupling agent Drying temperature (占 폚) / hour (minute) 100 parts by weight Kinds Content (parts by weight) Molecular weight (Mw) Kinds Content (parts by weight) Kinds Content (parts by weight) Kinds Content (parts by weight) Example 23 A1 B3 5 550 D-110N 0.1 Perroil TCP 0.3 - - 120/2 Example 24 A1 B4 5 900 D-110N 0.1 Perroil TCP 0.3 - - 120/2 Example 25 A1 B4 0.5 900 D-110N 0.1 Perroil TCP 0.3 - - 120/2 Example 26 A1 B4 30 900 D-110N 0.1 Perroil TCP 0.3 - - 120/2 Example 27 A1 B6 5 1300 D-110N 0.1 Perroil TCP 0.3 - - 120/2 Example 28 A1 B7 5 1400 D-110N 0.1 Perroil TCP 0.3 - - 120/2 Example 29 A1 B1 One 25000 D-110N 0.1 Perroil TCP 0.3 - - 120/2 Example 30 A1 B2 3 5000 D-110N 0.1 Perroil TCP 0.3 - - 120/2 Example 31 A1 B5 5 3200 D-110N 0.1 Perroil TCP 0.3 - - 120/2 Example 32 A1 B4 5 900 D-110N 0.1 Perroil TCP 0.05 - - 120/5 Example 33 A1 B4 5 900 D-110N 0.1 Perroil TCP 1.5 - - 120/2 Example 34 A1 B4 5 900 D-110N 0.1 Per butyl ND 0.3 - - 130/2 Example 35 A1 B4 5 900 D-110N 0.1 Perbutyl PV 0.3 - - 130/2 Example 36 A1 B4 5 900 D-110N 0.1 Perroil TCP 0.3 KBM-403 0.01 120/2 Example 37 A1 B4 5 900 D-110N 0.1 Perroil TCP 0.3 KBM-403 0.1 120/2 Example 38 A1 B4 5 900 D-110N 0.1 Perroil TCP 0.3 KBM-403 One 120/2

Adhesive resin The silicate oligomer (B) Cross-linking agent Peroxide-based crosslinking agent Silane coupling agent Drying temperature (占 폚) / hour (minute) 100 parts by weight Kinds Content (parts by weight) Molecular weight (Mw) Kinds Content (parts by weight) Kinds Content (parts by weight) Kinds Content (parts by weight) Example 39 A1 B4 5 900 D-110N 0.1 Perroil TCP 0.3 - - 140/2 Example 40 A7 B4 5 900 D-110N 0.1 Perroil TCP 0.3 - - 120/2 Example 41 A2 B4 5 900 D-110N 0.1 Perroil TCP 0.3 - - 120/2 Example 42 A2 B4 5 900 V-05 0.1 Perroil TCP 0.3 - - 120/2 Example 43 A2 B4 5 900 WS-500 0.1 Perroil TCP 0.3 - - 120/2 Example 44 A2 B4 5 900 Tetrad X 0.1 Perroil TCP 0.3 - - 120/2 Example 45 A3 B4 5 900 D-110N 0.1 Perroil TCP 0.3 - - 120/2 Example 46 A8 B4 5 900 D-110N 10 Perroil TCP 0.3 - - 120/2 Example 47 A9 B4 5 900 D-110N 10 Perroil TCP 0.3 - - 120/2 Comparative Example 9 A1 - - - D-110N 0.1 - - KBM-403 0.1 120/2 Comparative Example 10 A4 B4 5 900 D-110N 0.1 - - KBM-403 0.1 120/2 Comparative Example 11 A4 B4 5 900 D-110N 0.1 Perroil TCP 0.3 KBM-403 0.1 120/2 Comparative Example 12 A4 - - - D-110N 0.1 Perroil TCP 0.3 - - 120/2 Comparative Example 13 A5 B4 5 900 D-110N 0.1 Perroil TCP 0.3 KBM-403 0.1 120/2 Comparative Example 14 A5 B4 5 900 D-110N 0.1 Perroil TCP 0.3 - - 120/2 Comparative Example 15 A5 - - - D-110N 0.1 - - - - 120/2

In Table 7, V-05 is a carbodiimide type crosslinking agent manufactured by NISSHINBO, WS-500 is an oxazoline type crosslinking agent manufactured by Japan Catalyst, and Tetrad X is an epoxy type crosslinking agent manufactured by Mitsubishi Gas Chemical Company.

&Lt; Property evaluation method &

(1) Evaluation of Reliability, Adhesion and Re-workability Evaluation: The evaluation was carried out in the same manner as in Examples for the evaluation of reworkability and reliability, and is shown in Table 8.

(2) Calculation of gel fraction: The gel fraction was obtained by drying the pressure-sensitive adhesive composition at 100 占 폚 for 2 minutes so that the thickness after drying was 20 占 퐉 and crosslinking treatment to form a pressure-sensitive adhesive layer. And then it can be calculated by the following equation (1).

[Formula 1]

Gel fraction (% by weight) = {(Wc-Wa) / (Wb-Wa)} 100

(3) Evaluation of aging necessity (workability): If the gel fraction calculated above is 40 wt% or more, aging treatment is not required because there is no fear of pressure drop and durability deterioration. Therefore, the necessity of aging according to the gel fraction was evaluated as follows. The evaluation results are shown in Table 8.

○: When the gel fraction is 65% or more, there is no fear of pressure drop, workability, and durability deterioration

?: When the gel fraction is 40% or more and less than 65%, there is no fear of the pressing phenomenon

X: If the gel fraction is less than 40%, a pressing phenomenon may occur and workability and durability are deteriorated.

Here, the pressing phenomenon means that pressing is visually confirmed on the surface of the optical film when it is produced in the same manner as the adhesive optical film (sample) for A. workability and reliability evaluation, (420 mm.times.320 mm) as in the case of a pressure-sensitive adhesive optical film (sample) for evaluation of optical properties and reliability, and a square hole having a length of 270 mm on one side was punched in the optical film within one hour, It means that the adhesive property is felt or the surface of the polarizing film is contaminated.

(4) Measurement of PET oligomer precipitation amount: The adhesive polarizing film (including the separator) prepared above was allowed to stand at 60 DEG C and 90% RH for 500 hours, and then the separator was removed. Subsequently, about 0.025 g of the adhesive layer was taken from the adhesive polarizing film, and 1 ml of chloroform was added. After shaking at room temperature for 18 hours, 5 ml of acetonitrile was further extracted and shaken for 3 hours. The obtained solution was filtered with a 0.45 ml membrane filter, and a calibration curve was prepared by adjusting the standard of the trimer PET oligomer to a predetermined concentration, and the amount of the PET oligomer contained in the pressure-sensitive adhesive was requested using a calibration curve. The calibration curve was measured by HPLC (high performance liquid chromatography) using a sample having a known PET oligomer concentration (ppm). The HPLC apparatus, the measurement conditions of the HPLC, and the method of quantifying the PET oligomer amount are as follows.

HPLC apparatus: Agilent Technologies 1200 series

Measuring conditions

Column: ZORBAX SB-C18 from Agilent Technologies

Column temperature: 40 DEG C

Heat flow: 0.8 ml / min

Eluent composition: water / acetonitrile reverse phase gradient conditions

Injection amount: 5 μl

Detector: PDA (photodiode array)

Quantitative method: A standard sample of a PET oligomer trimer was dissolved in chloroform, diluted with acetonitrile, and the sample was adjusted to a constant concentration. A calibration curve was prepared from the HPLC area and the adjusted concentration. The amount of sample PET oligomer (deposition amount of oligomer in the pressure-sensitive adhesive layer) was determined along the calibration curve. The results are shown in Table 8.

responsibility Re-workability Gel fraction
(weight%) Workability Amount of oligomer precipitation
(ppm) Heating test Humidification test Heat shock test Initial adhesion
(N / 25 mm) Initial Actual Workability Adhesion after heating
(N / 25 mm) Actual reworkability after heating Example 23 ◎ ◎ ◎ 1.1 ◎ 1.9 ○ 69 ○ 8 Example 24 ◎ ◎ ◎ 0.5 ◎ 0.8 ◎ 70 ○ 8 Example 25 ○ ○ ○ 1.6 ◎ 2.5 ○ 72 ○ 8 Example 26 ○ ○ ○ 0.2 ◎ 0.4 ○ 71 ○ 8 Example 27 ◎ ◎ ◎ 1.9 ○ 2.8 ○ 75 ○ 8 Example 28 ◎ ◎ ◎ 2.3 ○ 2.9 △ 73 ○ 8 Example 29 ◎ ◎ ◎ 0.3 ◎ 0.9 ◎ 74 ○ 8 Example 30 ◎ ◎ ◎ 0.5 ◎ 1.3 ◎ 72 ○ 8 Example 31 ◎ ◎ ◎ 0.4 ◎ 0.9 ◎ 74 ○ 8 Example 32 ◎ ◎ ◎ 0.6 ◎ 1.5 ○ 42 ○ 8 Example 33 ◎ ◎ ◎ 0.4 ◎ 0.8 ◎ 92 ○ 8 Example 34 ◎ ◎ ◎ 0.5 ◎ 0.9 ◎ 55 ○ 8 Example 35 ◎ ◎ ◎ 0.4 ◎ 0.9 ◎ 45 ○ 8 Example 36 ◎ ◎ ◎ 0.5 ◎ 1.3 ◎ 74 ○ 8 Example 37 ◎ ◎ ◎ 0.8 ◎ 1.6 ○ 76 ○ 8 Example 38 ◎ ◎ ◎ 1.5 ○ 3.3 △ 75 ○ 8 Example 39 ◎ ○ ◎ One ◎ 1.5 △ 85 ○ 40 Example 40 ◎ ◎ ◎ 1.8 ○ 3.5 △ 77 ○ 8 Example 41 ◎ ◎ ◎ 2.2 ○ 3.8 △ 79 ○ 8 Example 42 ◎ ○ ◎ 1.9 ○ 2.7 ○ 81 ○ 8 Example 43 ◎ ○ ◎ 1.7 ○ 2.8 ○ 82 ○ 8 Example 44 ◎ ○ ◎ 1.9 ○ 2.7 ○ 81 ○ 8 Example 45 ◎ ○ ◎ 1.8 ○ 3.7 △ 85 ○ 8 Example 46 ◎ ○ ◎ 0.7 ◎ 1.1 ◎ 72 ○ 8 Example 47 ◎ ○ ◎ One ◎ 1.6 ◎ 70 ○ 8 Comparative Example 9 ○ ○ ○ 3 △ 6.5 × 0 × 8 Comparative Example 10 ◎ ◎ ◎ 4.5 × 9.2 × 0 × 8 Comparative Example 11 ◎ ◎ ◎ 5.2 × 10.9 × 75 ○ 8 Comparative Example 12 ○ ○ ○ 6.2 × 11.5 × 68 ○ 8 Comparative Example 13 ◎ ◎ ◎ 3.6 △ 5.1 × 72 ○ 8 Comparative Example 14 ◎ ○ ◎ 3.2 △ 4.5 × 69 ○ 8 Comparative Example 15 ○ △ ○ 2.2 ○ 4.5 × 0 × 8

As shown in Table 8, the pressure-sensitive adhesive composition according to Examples contains a viscous resin (A), a silicate oligomer (B) having an acid value of 0 mgKOH / g to 20.0 mgKOH / g as a base polymer and a peroxide-based crosslinking agent. In the adhesive optical film having the adhesive layer obtained from such a pressure-sensitive adhesive composition, since the adhesive layer contains the silicate oligomer (B), the adhesive force immediately after attaching the adhesive type optical film to the liquid crystal cell or the like can be made low. In addition, even if a long time has elapsed after passing through various processes or stored at a high temperature, the adhesive optical film can be easily peeled off from the liquid crystal cell or the like without increasing the adhesion to the liquid crystal cell and the like, and the reheat property is excellent. That is, the adhesive optical film can be reused without damaging or contaminating the liquid crystal cell. Particularly, it is difficult to peel the flat adhesion type optical film to a large liquid crystal cell. However, according to the present invention, the flat adhesion type optical film can easily be peeled off even in a large liquid crystal cell.

Further, in the present embodiment, when a coating film of a pressure-sensitive adhesive composition solution is heated and dried by incorporating a peroxide-based crosslinking agent in a specific ratio in a pressure-sensitive adhesive composition solution, aging is not required, workability is excellent, reworkability and reliability are excellent, A pressure-sensitive adhesive optical film having excellent handling properties in terms of process. Further, when the drying temperature is 130 占 폚 or less, the precipitation amount of the oligomer can be reduced in the pressure-sensitive adhesive layer.

While the preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, the present invention is not limited thereto. It will be apparent to those skilled in the art that various changes and modifications may be made without departing from the scope of the invention as defined in the appended claims. But it is understood that they fall within the technical scope of the present invention.

10: sticky optical film 11: optical film
12: adhesive layer 20: display device
21: display element 22: adhesive layer
23: Optical film 24: Adhesive layer
25: Optical film

Claims

A viscous resin having an acid value of 0 mgKOH / g to 20.0 mgKOH / g;
A silicate oligomer represented by the following formula (1); And
A crosslinking agent;
Sensitive adhesive composition for an optical film comprising:
[Chemical Formula 1]

The pressure-sensitive adhesive composition for an optical film according to claim 1, wherein the pressure-sensitive adhesive resin comprises at least one of a (meth) acrylic polymer, a urethane polymer and a polyester.

The pressure-sensitive adhesive composition for an optical film according to claim 2, wherein the (meth) acrylic polymer has a weight average molecular weight of 300,000 to 3,000,000.

The pressure-sensitive adhesive composition for an optical film according to claim 2, wherein the urethane polymer or the polyester has a weight average molecular weight of 10,000 to 200,000.

The pressure-sensitive adhesive composition for an optical film according to claim 1, wherein the pressure-sensitive adhesive resin contains a hydroxyl group-containing monomer as a constituent unit.

The pressure-sensitive adhesive composition for an optical film according to claim 1, wherein the pressure-sensitive adhesive resin has a glass transition temperature (Tg) of -100 ° C to -10 ° C.

The pressure-sensitive adhesive composition for an optical film according to claim 1, wherein the silicate oligomer has a weight average molecular weight of 300 to 30,000.

The silicate oligomer according to claim 1, wherein the silicate oligomer is a silicate oligomer in which R ₁ to R ₄ , X ₁ and X ₂ are methyl groups and a weight average molecular weight is 300 to 20,000, R ₁ to R ₄ , X ₁ and X ₂ is a methyl group and has a weight average molecular weight of more than 20,000 but not more than 30,000 and a silicate oligomer in which R ₁ , R ₂ , R ₃ , R ₄ , X ₁ or X ₂ is a silicate oligomer By weight of the pressure-sensitive adhesive composition.

The pressure-sensitive adhesive composition for an optical film according to claim 1, wherein the pressure-sensitive adhesive composition comprises 0.01 to 50 parts by weight of the silicate oligomer relative to 100 parts by weight of the pressure-sensitive adhesive resin.

The pressure-sensitive adhesive composition according to claim 1, wherein the pressure-sensitive adhesive composition comprises at least one of an isocyanate crosslinking agent, a carbodiimide crosslinking agent, an oxazoline crosslinking agent, an epoxy crosslinking agent and a peroxide crosslinking agent as the crosslinking agent in an amount of 0.01 To 20 parts by weight of the pressure-sensitive adhesive composition.

The pressure-sensitive adhesive composition for an optical film according to claim 1, wherein the pressure-sensitive adhesive composition comprises 0.02 to 2 parts by weight of a peroxide-based crosslinking agent based on 100 parts by weight of the pressure-sensitive adhesive resin.

The pressure-sensitive adhesive composition for an optical film according to claim 1, wherein the pressure-sensitive adhesive composition further comprises 0.001 to 10 parts by weight of the silane coupling agent per 100 parts by weight of the pressure-sensitive adhesive resin.

An adhesive layer formed from the pressure-sensitive adhesive composition for an optical film according to claim 1.

(Meth) acryl-based polymer, a urethane polymer, and a polyester;
A silicate oligomer represented by the following formula (1); And
A peroxide-based cross-linking agent;
And the pressure-sensitive adhesive layer is a pressure-sensitive adhesive layer formed by a crosslinking treatment of the pressure-
A pressure-sensitive adhesive layer having a gel fraction of from 40% by weight to 95% by weight according to the following formula 1 after standing for 1 hour from the formation of the pressure-sensitive adhesive layer at a temperature of 23 캜 and a humidity of 65%
[Chemical Formula 1]

Wherein R ₁ to R ₄ are each independently hydrogen, an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, X ₁ and X ₂ each independently represent hydrogen, An alkyl group or an aryl group having 6 to 20 carbon atoms, n is an integer of 1 to 100,
[Formula 1]
Gel fraction (% by weight) = {(Wc-Wa) / (Wb-Wa)} 100
In the above formula (1), Wb is the weight of the adhesive layer (0.2 g) packed with a fluororesin (TEMISHNTF-1122, manufactured by Nitto Denko) and Wa is the weight of the fluororesin. Further, Wc was obtained by immersing the adhesive layer containing the fluororesin in 40 ml of ethyl acetate at 23 DEG C for 7 days to extract the soluble fraction, drying the adhesive layer on the aluminum cup at 130 DEG C for 2 hours, It is the weight of the adhesive layer wrapped with the fluororesin in which the powder is removed.

15. The adhesive layer according to claim 14, wherein the point-initiating resin has an acid value of 0 mgKOH / g to 20.0 mgKOH / g.

The pressure-sensitive adhesive sheet according to claim 13 or 14, wherein the pressure-sensitive adhesive layer is a pressure-sensitive adhesive layer having a gel fraction of 65% by weight to 95% by weight after being left for 1 hour under conditions of a temperature of 23 캜 and a humidity of 65%
[Formula 1]
Gel fraction (% by weight) = {(Wc-Wa) / (Wb-Wa)} 100
In the above formula (1), Wb is the weight of the adhesive layer (0.2 g) packed with a fluororesin (TEMISHNTF-1122, manufactured by Nitto Denko) and Wa is the weight of the fluororesin. Further, Wc was obtained by immersing the adhesive layer containing the fluororesin in 40 ml of ethyl acetate at 23 DEG C for 7 days to extract the soluble fraction, drying the adhesive layer on the aluminum cup at 130 DEG C for 2 hours, It is the weight of the adhesive layer wrapped with the fluororesin in which the powder is removed.

15. The adhesive layer according to claim 13 or 14, wherein the adhesive layer has a difference between an initial adhesive force and an adhesive force after heating of 1 N / 25 mm or less.

The adhesive layer according to claim 13 or 14, wherein the adhesive layer has an adhesive strength of 3 N / 25 mm or less after heating.

The pressure-sensitive adhesive layer according to claim 13 or 14, wherein the pressure-sensitive adhesive layer has a thickness of 2 占 퐉 to 40 占 퐉.

A polarizer;
A protective layer formed on one surface of the polarizer;
An adhesive layer formed on the other surface of the polarizer;
/ RTI >
Wherein the pressure-sensitive adhesive layer is the pressure-sensitive adhesive layer according to any one of claims 13 to 14.

The adhesive optical film according to claim 20, wherein an adhesion-assisting layer is formed between the polarizer and the adhesive layer.

The method of claim 21, wherein the adhesion-assisting layer is formed on at least one of a surface of the polarizer and a surface of the adhesive layer,
And the adhesion-assisting layer is formed by corona treatment.

21. The adhesive optical film according to claim 20, wherein the protective layer is a transparent protective film or a protective coating layer.

A display device comprising the adhesive optical film according to any one of claims 20 to 23.