KR20190044425A - Adhesive composition, adhesive film and smart window comprising the same - Google Patents

Abstract

The present invention relates to an adhesive composition, capable of minimizing damage caused by ultraviolet rays, and to an adhesive film, and a smart window including the same. The adhesive composition of the present invention comprises: an acryl-based resin including a linear alkyl group-containing (meth)acrylate monomer polymerization unit, a branched alkyl group-containing (meth)acrylate monomer polymerization unit, and a polar functional group-containing monomer polymerization unit; a thermosetting agent; and an ultraviolet ray blocking agent.

Description

TECHNICAL FIELD [0001] The present invention relates to a pressure-sensitive adhesive composition, a pressure-sensitive adhesive film, and a smart window including the pressure-

TECHNICAL FIELD The present disclosure relates to a pressure sensitive adhesive composition, a pressure sensitive adhesive film and a smart window comprising the same.

Smart window refers to active control technology that can reduce energy loss by controlling the light transmittance from the outside and provide a comfortable environment for consumers. Especially smart window is used for automobile glass or architectural glass It is a technology that can be applied to parts requiring optical modulation effect of area.

Generally, smart windows include Polymer Dispersive Liquid Crystal. However, the polymer dispersed liquid crystal has a problem of being highly denatured when irradiated with ultraviolet rays.

In addition, a general adhesive film used for manufacturing a smart window has poor workability and is deformed under extreme conditions of high temperature and high humidity.

Thus, it is possible to prevent the problem that the polymer dispersed liquid crystal is modified by ultraviolet rays, that can be used for producing a smart window, securing ultraviolet shielding property, securing workability, And the need for further research is needed.

Patent Laid-Open Publication No. 10-2012-0077916

The present invention provides a pressure-sensitive adhesive composition, a pressure-sensitive adhesive film and a smart window.

It should be understood, however, that the present invention is not limited to the above-mentioned problems and other problems which are not mentioned can be understood by those skilled in the art from the following description.

An embodiment of the present invention is an acrylic resin comprising a polymerization unit of a linear alkyl group-containing (meth) acrylate monomer, a polymerization unit of a (meth) acrylate monomer having a branched chain alkyl group and a polymerization unit of a monomer having a polar functional group; Thermal curing agent; And an ultraviolet screening agent, wherein the content of the polymerization unit of the branched (meth) acrylate monomer is 30 parts by weight or more and 50 parts by weight or less based on 100 parts by weight of the acrylic resin.

An embodiment of the present invention provides an adhesive film comprising a cured product of the adhesive composition.

One embodiment of the present invention is an electrochromic film comprising a polymer dispersed liquid crystal layer and a conductive layer provided on both sides of the polymer dispersed liquid crystal layer; And a window substrate, wherein the window substrate and the electrochromic film are attached via the adhesive film.

INDUSTRIAL APPLICABILITY The adhesive composition according to one embodiment of the present invention can provide an adhesive film which is excellent in ultraviolet light shielding property and can minimize damage caused by ultraviolet rays of a conductive film including a polymer dispersed liquid crystal used in a smart window.

INDUSTRIAL APPLICABILITY The adhesive composition according to one embodiment of the present invention can provide an adhesive film which is excellent in workability and can be easily applied to a large area material such as automobile or architectural glass.

The pressure-sensitive adhesive composition according to one embodiment of the present invention can provide a pressure-sensitive adhesive film which does not deteriorate the adhesive properties even under the extreme conditions of high temperature and high humidity.

In this specification, when a part is referred to as " including " an element, it is to be understood that it may include other elements as well, without departing from the other elements unless specifically stated otherwise.

As used herein, the term " monomeric polymerization unit " means a monomeric unit derived from a monomer through polymerization to form a skeleton of the polymer, for example, a main chain or side chain.

In this specification, the unit " weight part " may mean the ratio of the weight between each component.

As used herein, the term " (meth) acrylate " may mean acrylate or methacrylate.

As used herein, the term " linear alkyl group " may include a carbon chain structure in which no unsaturated bond is present in the functional group and no additional functional group is bonded to the side chain, and a chain alkyl group having 1 to 20 carbon atoms in the main chain . ≪ / RTI >

In the present specification, the term "branched alkyl group" may mean a chain alkyl having a carbon chain structure in which an additional functional group is bonded to the side chain of the linear alkyl group and having 1 to 20 carbon atoms in the main chain.

In this specification, the term " solid content of acrylic resin " may refer to a solid non-volatile material contained in the acrylic resin, and may mean a residue after drying a solution containing the acrylic resin produced.

In the present specification, the " weight average molecular weight " may be a value converted to polystyrene measured by GPC (Gel Permeation Chromatography).

In the present specification, the glass transition temperature (Tg) was measured by raising the temperature at a heating rate of 5 캜 / min in a temperature range of -70 캜 to 100 캜 using DSC (DSC-STAR3, METTLER TOLEDO) May be a value determined by the midpoint of the DSC curve.

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

An embodiment of the present invention is an acrylic resin comprising a polymerization unit of a linear alkyl group-containing (meth) acrylate monomer, a polymerization unit of a (meth) acrylate monomer having a branched chain alkyl group and a polymerization unit of a monomer having a polar functional group; Thermal curing agent; And an ultraviolet screening agent, wherein the content of the polymerization unit of the branched (meth) acrylate monomer is 30 parts by weight or more and 50 parts by weight or less based on 100 parts by weight of the acrylic resin.

According to one embodiment of the present invention, the adhesive composition may include the acrylic resin.

Specifically, the acrylic resin may include a polymerization unit of a linear alkyl group-containing (meth) acrylate monomer, a polymerization unit of a (meth) acrylate monomer containing a branched chain alkyl group, and a monomer polymerization unit containing a polar functional group.

According to one embodiment of the present invention, the acrylic resin is one prepared by solution polymerization of a solution containing a linear alkyl group-containing (meth) acrylate monomer, a branched (meth) acrylate monomer containing a branched alkyl group and a monomer containing a polar functional group . The method of solution polymerization is not particularly limited, and the acrylic resin may be produced through a known polymerization method such as thermal polymerization, photopolymerization or thermal polymerization of the solution and dual polymerization of photopolymerization.

According to an embodiment of the present invention, the solution for producing the acrylic resin may further include a polymerization initiator.

The type of the polymerization initiator is not particularly limited, and may be selected from thermal polymerization initiators or photopolymerization initiators generally used in the art.

According to one embodiment of the present invention, the linear alkyl group-containing (meth) acrylate monomer may be a form in which the linear alkyl group described above is bonded to (meth) acrylate.

The content of the linear alkyl group-containing (meth) acrylate monomer may be the same as the content of the linear alkyl group-containing (meth) acrylate monomer.

According to one embodiment of the present invention, the linear alkyl group-containing (meth) acrylate monomer is at least one selected from the group consisting of methyl (meth) acrylate, ethyl (meth) acrylate, , n-pentyl (meth) acrylate, n-hexyl (meth) acrylate, n-heptyl (meth) acrylate and n-octyl (meth) acrylate. However, it is not limited thereto, and it may be appropriately selected from (meth) acrylate monomers to which a linear alkyl group generally known in the art is bonded.

According to one embodiment of the present invention, the linear alkyl group-containing (meth) acrylate monomer can be bonded to the basic skeleton of the acrylic resin, thereby improving the mechanical durability and adhesion properties of the acrylic resin.

According to one embodiment of the present invention, the branched alkyl group-containing (meth) acrylate monomer may be in a form in which the above-mentioned branched alkyl group is bonded to (meth) acrylate.

In addition, the content of the polymeric units of the branched (meth) acrylate monomer containing the branched chain alkyl groups may be the same as the content of the (meth) acrylate monomers containing the branched chain alkyl groups.

According to one embodiment of the present invention, the branched (meth) acrylate monomer containing a branched chain alkyl group is selected from the group consisting of t-butyl (meth) acrylate, sec- (Meth) acrylate, isopentyl (meth) acrylate, isohexyl (meth) acrylate and isononyl (meth) acrylate. However, it is not limited thereto, and may be appropriately selected from (meth) acrylate monomers to which a branched chain alkyl group generally known in the art is bonded.

According to one embodiment of the present invention, the (meth) acrylate monomer containing a branched chain alkyl group can form the basic skeleton of the acrylic resin, thereby securing the mechanical durability of the acrylic resin.

According to one embodiment of the present invention, the polar functional group-containing monomer may be in a form in which a polar functional group is bonded.

The content of the polar functional group-containing monomer may be the same as the content of the polar functional group-containing monomer.

According to one embodiment of the present invention, the polar functional group-containing monomer may include at least one of a hydroxyl group-containing monomer, a carboxyl group-containing monomer and a nitrogen-containing monomer.

According to one embodiment of the present invention, the hydroxy group-containing monomer is at least one monomer selected from the group consisting of 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (Meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyleneglycol (meth) acrylate, , But is not limited thereto.

According to one embodiment of the present invention, the carboxyl group-containing monomer is at least one selected from the group consisting of acrylic acid, methacrylic acid, 2- (meth) acryloyloxyacetic acid, 3- (meth) acryloyloxypropyl acid, 4- But is not limited to, at least one of dioxybutyl acid and acrylic acid condensate.

According to one embodiment of the present invention, the nitrogen-containing monomer is at least one monomer selected from the group consisting of 2-isocyanatoethyl (meth) acrylate, 3-isocyanatopropyl (meth) acrylate, 4-isocyanatobutyl Acrylate, (meth) acrylamide, N-vinylpyrrolidone, and N-vinylcaprolactam.

According to one embodiment of the present invention, the polar functional group-containing monomer may be bonded to the basic skeleton of the acrylic resin, and the adhesive property of the acrylic resin may be improved.

According to one embodiment of the present invention, the content of the polymerization unit of the (meth) acrylate monomer containing the branched chain alkyl group is from 30 to 50 parts by weight, more preferably from 30 to 45 parts by weight based on 100 parts by weight of the acrylic resin , 35 parts by weight or more and 50 parts by weight or less, or 35 parts by weight or more and 45 parts by weight or less.

Within the above range, the pressure-sensitive adhesive film containing the cured product of the pressure-sensitive adhesive composition containing the acrylic resin can secure high mechanical properties, high adhesive properties and excellent workability even under extreme conditions of high temperature and high humidity.

According to one embodiment of the present invention, the content of the polymerization unit of the linear alkyl group-containing (meth) acrylate monomer is 40 parts by weight or more and 60 parts by weight or less, 40 parts by weight or more and 55 parts by weight or less , 45 parts by weight or more and 60 parts by weight or less, or 45 parts by weight or more and 55 parts by weight or less.

Within the above range, the glass transition temperature of the acrylic resin can be controlled, and the resulting adhesive film can secure high mechanical properties, high adhesive properties and excellent workability even under extreme conditions of high temperature and high humidity.

In addition, compatibility with the ultraviolet screening agent contained in the adhesive composition is ensured, and even if the ultraviolet screening agent is included, the adhesive property and the mechanical properties are not reduced, and the excellent workability of the adhesive film can be maintained.

According to one embodiment of the present invention, the content of the polar functional group-containing monomer is not less than 0.1 parts by weight and not more than 10 parts by weight, more preferably not less than 0.1 parts by weight nor more than 7 parts by weight, more preferably not less than 5 parts by weight, By weight or less, or 5 parts by weight or more and 7 parts by weight or less.

It is possible to improve the chemical bonding force between the components in the adhesive composition comprising the acrylic resin within the above range and to improve the adhesive strength of the adhesive film thus produced and to secure the workability at the same time. In particular, when the amount is less than the above range, there may arise a problem that a sufficient adhesive force can not be realized on the adherend, and when it exceeds the above range, the adhesive force to the adherend excessively increases, .

According to one embodiment of the present invention, the acrylic resin has a weight average molecular weight of 1,000,000 g / mol to 1,300,000 g / mol, 1,000,000 g / mol to 1,200,000 g / mol, 1,100,000 g / mol to 1,300,000 g / mol, Or from about 1,100,000 to 1,200,000 g / mol.

Within the above range, it is possible to secure high adhesive strength and excellent durability of the pressure-sensitive adhesive film made of the acrylic resin.

According to one embodiment of the present invention, the acrylic resin has a glass transition temperature of -30 ° C to -5 ° C, -30 ° C to -10 ° C, -20 ° C to -5 ° C, or -20 ° C to + 20 ° C or less.

Within the above range, since the acrylic resin has a relatively flexible physical property, the reliability of the adhesive film produced from the acrylic resin can be secured.

According to one embodiment of the present invention, the adhesive composition may comprise a thermosetting agent. Specifically, the pressure-sensitive adhesive composition may include the acrylic resin and the heat curing agent described above.

By including the thermosetting agent, the adhesive composition can be thermally cured and then made into an adhesive film.

According to one embodiment of the present invention, the adhesive composition may not contain a photo-curing agent. That is, the crosslinking reaction between the components contained in the adhesive composition may not be caused by light irradiation.

Accordingly, the adhesive film containing the cured product of the pressure-sensitive adhesive composition may not be caused to react even by ultraviolet irradiation, and variations in mechanical properties and adhesive properties may be minimized by ultraviolet irradiation.

According to one embodiment of the present invention, the thermosetting agent may include at least one of an aziridine type thermosetting agent, an isocyanate type thermosetting agent and an epoxy type thermosetting agent, and may preferably include an aziridine type thermosetting agent.

According to one embodiment of the present invention, the isocyanate-based thermosetting agent is selected from the group consisting of an aliphatic isocyanate thermosetting agent, an alicyclic isocyanate thermosetting agent, an aromatic isocyanate thermosetting agent, a sulfated aromatic isocyanate thermosetting agent, a sulfated aliphatic isocyanate thermosetting agent, And a recurring aromatic isocyanate-based thermosetting agent. However, it is not limited thereto and can be freely selected among isocyanate-based thermosetting agents known in the art.

According to one embodiment of the present invention, the aziridine-based thermosetting agent is selected from the group consisting of N, N'-toluene-2,4-bis (1-aziridine carboxamide), N, N'- -Bis (1-aziridine carboxamide), triethylene melamine, bisisopropanoyl-1- (2-methyl aziridine) and tri-1-aziridinyl phosphine oxide . However, it is not limited thereto and aziridine-based thermosetting agents known in the art can be freely selected.

According to one embodiment of the present invention, the epoxy thermosetting agent is selected from the group consisting of ethylene glycol diglycidyl ether, triglycidyl ether, trimethylol propane triglycidyl ether, N, N, N ', N'-tetraglycidyl Ethylene diamine, and glycerin diglycidyl ether. However, it is not limited thereto and may be freely selected among epoxy-based thermosetting agents known in the art.

According to one embodiment of the present invention, the content of the thermosetting agent is 0.1 parts by weight or more and 1 part by weight or less, 0.1 parts by weight or more and 0.7 parts by weight or less, 0.3 parts by weight or more and 1 part by weight or less , And 0.3 parts by weight or more and 0.7 parts by weight or less.

Within the above range, the durability and adhesive force of the pressure-sensitive adhesive film produced using the pressure-sensitive adhesive composition can be secured at the same time. Specifically, when the above range is not reached, the curing of the pressure-sensitive adhesive film is not sufficiently progressed and reliability of the adherend can not be ensured in an environment of high temperature and high humidity. When the pressure-sensitive adhesive layer is out of the above range, The adhesive force of the adhesive layer may decrease.

According to one embodiment of the present invention, the adhesive composition may comprise a sunscreen agent. That is, the adhesive composition may include the acrylic resin, the thermosetting agent, and the ultraviolet screening agent.

According to one embodiment of the present invention, the adhesive composition includes the ultraviolet screening agent, so that the adhesive film comprising the cured product of the pressure-sensitive adhesive composition can realize the ultraviolet screening property. The adhesive film has an ultraviolet shielding property, thereby minimizing the modification of the polymer dispersed liquid crystal contained in the conductive film adhering to the base film by ultraviolet irradiation.

In addition, the ultraviolet shielding property of the adhesive film can be quantified by a light transmittance at a specific wavelength to be described later.

According to one embodiment of the present invention, the ultraviolet light blocking agent may be at least one compound selected from an oxanilide compound, a benzophenone compound, a benzotriazole compound and a triazine compound. Specifically, the triazine compound may be a hydroxyphenyl -S-triazine-based compound.

In particular, when the pressure-sensitive adhesive composition contains the hydroxyphenyl-S-triazine compound as an ultraviolet screening agent, the pressure-sensitive adhesive film containing the cured product of the pressure-sensitive adhesive composition can maintain excellent adhesive property and excellent mechanical durability, It is possible to secure the blocking characteristic.

According to one embodiment of the present invention, the oxanilide compound is at least one compound selected from the group consisting of 4,4'-dioctyloxyoxanilide, 2,2'-diethoxyoxanilide, 2,2'-dioctyloxy- Di-tert-butoxanilide, 2,2'-didodecyloxy-5,5'-di-tert-butoxanilide, 2-ethoxy-2'-ethyloxanilide, N, N Ethoxy-5-tert-butyl-2'-ethoxanilide and their 2-ethoxy-2'-ethyl-5,4'-di- tert-butoxanilide, mixtures of o- and p-methoxy-disubstituted oxanilides and mixtures of o- and p-ethoxy-disubstituted oxanilides. However, it is not limited thereto and can be freely selected among the oxanilide compounds known in the art.

According to one embodiment of the present invention, the benzophenone compound is selected from the group consisting of benzophenone, benzhydrol, 4-hydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2,4-dihydroxybenzophenone , 2,2'-dihydroxy-4-methoxybenzophenone, and 2,3,4-trihydroxybenzophenone. However, it is not limited thereto and may be freely selected among benzophenone compounds known in the art.

According to one embodiment of the present invention, the benzotriazole-based compound is 2- (2'-hydroxy-5'-methacryloxyethylphenyl) -2H-benzotriazole and N- [3-benzotriazol- -Yl-2-hydroxy-5- (1,1,3,3-tetramethylbutyl) -benzyl] -2-methylacrylamide. However, it is not limited thereto and may be freely selected among benzotriazole-based compounds known in the art.

According to one embodiment of the present invention, the hydroxyphenyl-S-triazine compound is 2,6-bis- (2,4-dimethylphenyl) -4- (2- s-triazine; 2,6-bis- (2,4-dimethylphenyl) -4- (2,4-dihydroxyphenyl) -s-triazine; 2,4-bis (2,4-dihydroxyphenyl) -6- (4-chlorophenyl) -s-triazine; 2,4-bis [2-hydroxy-4- (2-hydroxyethoxy) phenyl] -6- (4-chlorophenyl) -s-triazine; (2,4-dimethylphenyl) -s-triazine; 2,4-bis [2-hydroxy-4- 4-bis [2-hydroxy-4- (2-hydroxyethoxy) -phenyl] -6- (4-bromophenyl) - (2-acetoxyethoxy) phenyl] -6- (4-chlorophenyl) -s-triazine and 2,4-bis (2,4-dihydroxyphenyl) Dimethylphenyl) -s-triazine. ≪ / RTI >

According to one embodiment of the present invention, the content of the ultraviolet screening agent is 0.1 parts by weight or more and 10 parts by weight or less, 0.1 parts by weight or more and 7 parts by weight or less, 0.1 parts by weight or more and 5 parts by weight or less 0.5 to 10 parts by weight, 0.5 to 7 parts by weight, 0.5 to 5 parts by weight, 1 to 10 parts by weight, 1 to 7 parts by weight, or 1 part by weight And 5 parts by weight or less.

Within the above range, the ultraviolet screening agent contained in the adhesive composition can improve the compatibility with the acrylic resin, thereby providing a pressure-sensitive adhesive film that ensures workability, reliability under extreme conditions of high temperature and high humidity, and ultraviolet barrier property . Concretely, when it exceeds the above range, the optical visibility may be deteriorated.

According to one embodiment of the present invention, the adhesive composition may further comprise a solvent. That is, the adhesive composition may include an acrylic resin, a thermosetting agent, an ultraviolet screening agent, and a solvent. In addition, the type of the solvent is not particularly limited and may be appropriately selected from among solvents generally known in the art for producing a pressure-sensitive adhesive composition.

According to one embodiment of the present invention, the pressure-sensitive adhesive composition further includes a solvent, so that an appropriate viscosity for coating with the pressure-sensitive adhesive film can be realized.

Another embodiment of the present invention provides an adhesive film.

An embodiment of the present invention provides a pressure-sensitive adhesive film comprising a cured product of the pressure-sensitive adhesive composition.

According to one embodiment of the present invention, the adhesive film may include thermosetting of the adhesive composition.

Further, according to one embodiment of the present invention, the adhesive composition may not be photo-cured even when irradiated with light.

According to one embodiment of the present invention, the adhesive film may be formed by inducing a crosslinking reaction by applying heat to the adhesive composition, followed by curing, i.e., thermosetting. As a method of forming the adhesive film by thermosetting the adhesive composition, a thermal curing method known in the art can be used.

According to one embodiment of the present invention, the light transmittance of the adhesive film at a wavelength of 380 nm may be 5% or less. That is, the adhesive film may have a transmittance of light having an ultraviolet wavelength region of 5% or less, which means that the light blocking rate of the ultraviolet wavelength region of the adhesive film is 95% or more.

In the present specification, the term " light transmittance " may mean, when a light having a specific wavelength is irradiated on an irradiated object, a light amount of light transmitted through the irradiated object with respect to a light amount irradiated to the irradiated object as a percentage have. That is, the above-mentioned " light transmittance at a wavelength of 380 nm " may be a percentage of the amount of light transmitted through the object to be irradiated to the irradiated object of light having a wavelength of 380 nm.

Another embodiment of the present invention provides a smart window.

One embodiment of the present invention is an electrochromic film comprising a polymer dispersed liquid crystal layer and a conductive layer provided on both sides of the polymer dispersed liquid crystal layer; And a window substrate, wherein the window substrate and the electrochromic film are attached via the adhesive film.

According to an embodiment of the present invention, the smart window may include an electrochromic film, an adhesive film, and a window substrate sequentially.

According to one embodiment of the present invention, the electrochromic film may include a polymer dispersed liquid crystal layer, and may include a conductive layer. In addition, the conductive layer may be provided on both sides of the polymer dispersed liquid crystal layer.

According to an exemplary embodiment of the present invention, the conductive layer is a metal oxide such as ITO (indium tin oxide), AZO (antimony-doped zinc oxide), ATO (antimony-doped tin oxide), SnO, RuO 2, IrO 2 But can be selected without limitation as long as it is capable of forming an electric field for controlling the alignment of the liquid crystal, capable of supplying electric charge, and having excellent adhesion with the pressure-sensitive adhesive film and known in the art.

According to an embodiment of the present invention, the polymer dispersed liquid crystal layer may be one in which a micrometer-sized liquid crystal is dispersed in a polymer matrix, and the liquid crystal and the polymer are phase-separated from a mixture containing the polymer and the liquid crystal Lt; / RTI >

According to an embodiment of the present invention, the polymer dispersed liquid crystal layer may include a polymer network liquid crystal (PNLC) or a polymer stabilized liquid crystal (PSLC).

According to an embodiment of the present invention, the window substrate may be formed of a material selected from the group consisting of polyethylene terephthalate (PET), triacetyl cellulose (TAC), cycloolefin polymer (COP), poly (methyl methacrylate ) {Poly (methyl methacrylate); (PMMA), polycarbonate (PC), poly ethylene (PE), polypropylene (PP), polyvinyl acetate (PVA), polyether sulfone And may include at least one of polyethyleneimide (PEI) and polyimide (PI). However, the present invention is not limited thereto, and it can be selected freely from a plastic film having a high ultraviolet transmittance, which can realize a bending property.

When the ultraviolet ray is irradiated in the direction of the adhesive film from the window substrate, the smart window is sequentially irradiated with the ultraviolet ray blocking property of the adhesive film by sequentially providing the electrochromic film, the adhesive film and the window substrate as described above The ultraviolet rays can be blocked by the adhesive film, and thus damage to the polymer dispersed liquid crystal layer contained in the electrochromic film can be minimized.

According to an embodiment of the present invention, the adhesive force of the adhesive film to the electrochromic film may be greater than the adhesive force of the adhesive film to the window substrate.

Accordingly, even if the adhesive film is peeled from the window substrate, the adhesive film can be peeled while minimizing the residue of the adhesive film appearing on the window substrate.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail with reference to examples. However, the embodiments according to the present invention can be modified into various other forms, and the scope of the present invention is not construed as being limited to the embodiments described below. Embodiments of the present disclosure are provided to enable those skilled in the art to more fully understand the present invention.

< Manufacturing example >

Manufacturing example  One

As the monomer, a composition comprising 40 parts by weight of 2-ethylhexyl acrylate, 55 parts by weight of methyl acrylate and 5 parts by weight of acrylic acid was polymerized to prepare an acrylic resin.

The acrylic resin had a weight average molecular weight of 1,200,000 g / mol and a glass transition temperature of -15 ° C.

Manufacturing example  2

As the monomer, a composition comprising 45 parts by weight of 2-ethylhexyl acrylate, 50 parts by weight of methyl acrylate and 5 parts by weight of acrylic acid was polymerized to prepare an acrylic resin.

The acrylic resin had a weight average molecular weight of 1,200,000 g / mol and a glass transition temperature of -19 ° C.

Manufacturing example  3

As the monomer, a composition comprising 65 parts by weight of 2-ethylhexyl acrylate, 25 parts by weight of methyl acrylate and 10 parts by weight of acrylic acid was polymerized to prepare an acrylic resin.

The acrylic resin had a weight average molecular weight of 1,200,000 g / mol and a glass transition temperature of -29 ° C.

< Example  And Comparative Example >

Example  One

(Tinuvin 477, manufactured by BASF) and about 2 parts by weight of an aziridine-based thermosetting agent based on 100 parts by weight of the acrylic resin according to Preparation Example 1 and about 2 parts by weight of a hydroxy-S-triazine-based ultraviolet screening agent A composition was prepared.

Example  2

A pressure-sensitive adhesive composition was prepared in the same manner as in Example 1, except that the acrylic resin according to Production Example 2 was used.

Comparative Example  One

A pressure-sensitive adhesive composition containing only the acrylic water according to Production Example 1 was prepared.

Comparative Example  2

A pressure-sensitive adhesive composition was prepared in the same manner as in Example 1, except that the acrylic resin according to Production Example 3 was used.

Comparative Example  3

A pressure-sensitive adhesive composition containing only acrylic water according to Production Example 3 was prepared.

< Experimental Example  And evaluation>

A pressure-sensitive adhesive film having a thickness of 25 占 퐉, prepared by curing the pressure-sensitive adhesive composition according to Examples 1 to 2 and Comparative Examples 1 to 3 at a temperature of about 80 占 폚 to 110 占 폚 for about 1.5 minutes, Adhesive tapes bonded to both sides of a polyethylene terephthalate (PET) substrate were prepared, and the physical property evaluation results thereof are shown in Table 1 below.

division Construction responsibility UV barrier property Example 1 ○ ○ ○ Example 2 ○ ○ ○ Comparative Example 1 ○ ○ X Comparative Example 2 X ○ ○ Comparative Example 3 X ○ X

Construction evaluation

After spraying the surface active agent onto a 35 cm X 30 cm (width X length), 1.1 T thick glass substrate having no printed steps, the glass substrate was cut to the above 25 cm X 30 cm (width X length) An adhesive tape and an ITO (Indium Tin Oxide) film were sequentially laminated. When the adhesive tape and the ITO film were peeled off, the case where the adhesive tape was easily peeled off and the residue of the adhesive tape remained on the glass substrate was evaluated as O, and the case where the adhesive tape remained on the glass substrate was not easily peeled off was evaluated as X .

Reliability evaluation

The adhesive tape prepared on the hardcoat PET film was attached, and a 0.55 T thick glass substrate was laminated thereon. A case where bubbles were generated after putting in a thermostat / hygrostat under the conditions of 85 캜 and 85 RH% was evaluated as X, and a case where no bubbles were generated between glass substrates was evaluated as?.

UV barrier evaluation

After attaching the adhesive tape to a glass substrate having a thickness of 1.1 T having no printing step, ultraviolet rays having a wavelength of 250 to 1,000 nm were irradiated using a UV-Vis spectrometer at a temperature of about 20 to 30 DEG C, , And when the light transmittance at a wavelength of 385 nm was less than 5%, it was evaluated as?, And when it exceeded 5%, it was evaluated as X. [

According to Table 1, Examples 1 and 2 including an acrylic resin and an ultraviolet screening agent produced according to one embodiment of the present invention are excellent in workability, reliability under extreme conditions of high temperature and humidity, and UV barrier property I could confirm.

On the other hand, Comparative Example 1, which does not contain a UV blocking agent, has a problem that the UV blocking property can not be secured although the workability and reliability are comparatively excellent. Accordingly, it was confirmed that the adhesive composition according to one embodiment of the present invention must contain the above-described ultraviolet screening agent.

In addition, in the case of Comparative Example 2 containing an acrylic resin deviating from the content of polymerized units of (meth) acrylate monomers according to one embodiment of the present invention, UV barrier property can be ensured by including an ultraviolet screening agent, The residual adhesive tape remains on the glass substrate due to an increase in the adhesion of the adhesive tape to the glass substrate, thereby deteriorating the workability.

Furthermore, unlike Comparative Example 2 of the present invention, Comparative Example 3 containing no ultraviolet screening agent showed only reliability under extreme conditions, but was not excellent in reliability and UV blocking property.

According to the evaluation results of Comparative Example 2 and Comparative Example 3, when the mixing ratio of the acrylic resin, specifically, the content of the polar functional group-containing monomer such as acrylic acid contained therein is increased, the workability is lowered. Therefore, It has been confirmed that it is necessary to adjust to the range according to one embodiment of the present invention.

That is, in order to comprehensively summarize the above results, it is necessary to include an ultraviolet screening agent for UV shielding. In order to maintain the excellent adhesive property, the composition of the acrylic resin contained in the adhesive composition is changed according to an embodiment of the present invention It can be confirmed that it should be adjusted to the range.

Claims (12)

An acrylic resin containing a polymerization unit of a linear alkyl group-containing (meth) acrylate monomer, a polymerization unit of a (meth) acrylate monomer containing a branched chain alkyl group and a polymerization unit of a monomer having a polar functional group; Thermal curing agent; And an ultraviolet screening agent,
Wherein the content of the polymerization unit of the (meth) acrylate monomer containing the branched-chain alkyl group is from 30 to 50 parts by weight based on 100 parts by weight of the acrylic resin. The method according to claim 1,
Wherein the ultraviolet screening agent comprises at least one compound selected from an oxalanilide compound, a benzophenone compound, a benzotriazole compound and a triazine compound. The method according to claim 1,
Wherein the content of the ultraviolet screening agent is 0.1 parts by weight or more and 10 parts by weight or less based on 100 parts by weight of the solid content of the acrylic resin. The method according to claim 1,
Wherein the content of the polymerization unit of the linear alkyl group-containing (meth) acrylate monomer is 40 parts by weight or more and 60 parts by weight or less based on 100 parts by weight of the acrylic resin. The method according to claim 1,
Wherein the content of the polar functional group-containing monomer is 0.1 part by weight or more and 10 parts by weight or less based on 100 parts by weight of the acrylic resin. The method according to claim 1,
Wherein the content of the thermosetting agent is 0.1 parts by weight or more and 1 part by weight or less based on 100 parts by weight of the solid content of the acrylic resin. The method according to claim 1,
Wherein the thermosetting agent comprises at least one of an aziridine thermosetting agent, an isocyanate thermosetting agent and an epoxy thermosetting agent. The method according to claim 1,
Wherein the acrylic resin has a weight average molecular weight of 1,000,000 g / mol or more and 1,300,000 g / mol or less. The method according to claim 1,
Wherein the acrylic resin has a glass transition temperature of -30 占 폚 to -5 占 폚. A pressure-sensitive adhesive film comprising a cured product of the pressure-sensitive adhesive composition according to claim 1. The method of claim 10,
Wherein the adhesive film has a light transmittance of 5% or less at a wavelength of 380 nm. An electrochromic film comprising a polymer dispersed liquid crystal layer and a conductive layer provided on both sides of the polymer dispersed liquid crystal layer; And a window substrate,
Wherein the window substrate and the electrochromic film are attached through the adhesive film according to claim 10.