KR20160150499A - The conductive film - Google Patents

Abstract

The present invention relates to a conductive film, a method for manufacturing the conductive film, and a usage thereof. The present invention can provide the conductive film which can improve a visibility problem caused by a pattern pushing phenomenon or the like after a heat treatment process, the method for manufacturing the conductive film, and the usage thereof. The conductive film comprises: a base film; a first resin layer formed in one surface of the base film; and a second resin layer formed in a surface in which the first resin layer of the base film is not formed.

Description

CONDUCTIVE FILM [0002]

The present application relates to a conductive film, a method for producing the conductive film, and uses thereof.

A touch screen panel (TSP) is an input device of an operating system that allows a user to easily input data by simply touching the screen (screen) with a hand or an object. The touch screen panel (TSP) (Resistive), and capacitive (Capacitive).

Among them, Resistive and Capacitive are the most widely used methods. Resistive method is to detect when a potential difference occurs at a pressed point when touching with a finger or a pen. It is a principle and it is called a decompression type.

In addition, the electrostatic capacity type uses the electrostatic capacity in the human body to sense and change the direction of the current.

An indium-tin oxide (ITO) film commonly used in the structure of the resistive film type and capacitive touch screen panel is formed by depositing a transparent conductive film made of indium tin compound, which is a metal conductive material, And a transparent electrode (electric circuit, pattern) is formed on the base substrate.

Particularly, in the capacitance type, visibility of a transparent electrode (electric circuit, pattern) becomes a problem. In order to improve the visibility, an optical control layer is formed on a lower surface of a conductive layer such as an ITO layer to minimize the reflectance of a film surface that has been etched (patterning) and a surface that is not etched .

Further, in the conductive film, in addition to the optical control layer, a layer such as a transparent undercoating layer is formed under the conductive layer to improve the adhesion and transmittance between the conductive layer and the base layer. The undercoat layer can be formed by wet coating or vacuum stuttering. However, since the steps for forming each layer need to be performed separately, the manufacturing process is complicated and the cost is high.

In addition, despite the above-mentioned efforts to improve the visibility, there is still a problem that the ITO layer may be pressed on the patterned substrate portion during the heat treatment process after the patterning of the ITO layer, thereby lowering the visibility.

(Patent Document 1) Korean Patent Publication No. 2010-0134692

The present application provides a conductive film and a method for producing the conductive film which overcome the problem of lowering the visibility due to the bending phenomenon of the conductive film.

The present application also provides a use of a donor film, for example, a touch panel including a conductive film.

The present application has been conceived to solve the above problems, and includes a base film; A first resin layer formed on one surface of the base film; And a second resin layer formed on a surface of the base film on which the first resin layer is not formed. The conductive film has a thermal expansion coefficient of 15 ppm / ° C or less.

In one example, the ratio (T1 / T2) of the thickness (T1) of the first resin layer and the thickness (T2) of the second resin layer may be in the range of 0.75 to 1.30.

In one example, the absolute value of the difference between the refractive index (based on 550 nm wavelength) of the first resin layer and the refractive index (based on 550 nm wavelength) of the base film may be 0.3 or less.

In one example, the ratio of the inorganic particles in the first resin layer may be 60% by weight or more.

The conductive film of the present application may further include, for example, a conductive layer on the first resin layer.

The conductive film of the present application may further include, for example, an undercoat layer between the first resin layer and the conductive layer.

The present application also relates to a method for producing a conductive film comprising a step of forming a first resin layer and a second resin layer on both sides of a base film and having a thermal expansion coefficient of 15 ppm / ° C or lower.

The present application also relates to a touch panel including a conductive film.

The present application can prevent a visibility problem due to a bending phenomenon that may be caused by heat treatment and the like, thereby providing a conductive film having excellent visibility, a method for producing the conductive film, and its use.

1 (a) and 1 (b) are schematic diagrams of a known conductive film.
2 is a schematic diagram of the conductive film of the present application.

Hereinafter, the present application will be described in more detail by way of examples, but is merely an example limited to the gist of the present application. It will be apparent to those skilled in the art that the present application is not limited to the process conditions set forth in the following examples, and may be arbitrarily selected within the range necessary for achieving the object of the present application .

The present application relates to a conductive film and a method for producing the same.

The present invention can provide a conductive film in which the problem of visibility due to a pattern pressing phenomenon that may occur in a predetermined heat treatment process after deposition of a conductive layer and patterning is improved, and a method of manufacturing the conductive film.

1 is a schematic diagram of a conventional conductive film. 1 (a) and 1 (b), when a typical conductive film is subjected to a predetermined heat treatment process, the conductive film is curved in the direction of the conductive layer as shown in FIG. 1 (a) A pressing phenomenon may occur in the pattern portion of the conductive layer such as curved in the direction opposite to the direction of the conductive layer. In addition, a visibility problem in which the pattern portion of the conductive layer is visually recognized due to the pressing phenomenon of such a pattern may occur.

However, in the conductive film according to the present application, a predetermined resin layer is formed on both sides of the base film, the thickness of the resin layer, the content of the inorganic particles, and the like are controlled to keep the thermal expansion coefficient of the conductive film below a predetermined range, The bending phenomenon of the conductive film due to the heat treatment process can be minimized and ultimately the pattern visibility problem of the conductive film can be improved.

That is, the present application relates to a base film; A first resin layer formed on one surface of the base film; And a second resin layer formed on a surface of the base film on which the first resin layer is not formed, and having a thermal expansion coefficient of 15 ppm / ° C or lower.

The conductive film of the present application comprises a base film and includes a first resin layer and a second resin layer on both sides of the base film respectively. The first resin layer and the second resin layer are for distinguishing between two resin layers having different physical properties formed on both sides of a base film. For example, a resin layer formed on a later-described conductive layer side is referred to as a first resin layer And the resin layer formed on the opposite surface can be referred to as a second resin layer.

The conductive film of the present application includes a base film.

In one example, the base film may be a transparent film, and a known one suitable for a conductive film having transparency and strength in an appropriate range may be employed.

Specifically, the base film may be made of polyolefin such as polyethylene or polypropylene; Polyesters such as polyethylene terephthalate and polyethylene naphthalate; Polyamides such as 6-nylon or 6,6-nylon; Polycarbonate; Polyethersulfone; Or a norbornene resin can be used, but the present invention is not limited thereto. These base films may be used alone or in combination of two or more. The base film may also be in the form of a single film or a laminated film.

The base film of the present application may also be one whose surface has been modified.

In one example, the substrate film may be a surface modified by a known treatment method such as a chemical treatment, a corona discharge treatment, a mechanical treatment, an ultraviolet (UV) treatment, an active plasma treatment or a glow discharge treatment.

Further, the base film may contain known additives such as an antistatic agent, an ultraviolet absorber, an infrared absorber, a plasticizer, a lubricant, a colorant, an antioxidant or a flame retardant.

The thickness of the base film may be set to a suitable thickness range in consideration of transparency, the purpose of minimizing the occurrence of thinning and the occurrence of wrinkles due to tension during processing, and the like. In one example, the substrate film may have a thickness ranging from 10 占 퐉 to 80 占 퐉, or from 20 占 퐉 to 60 占 퐉, but is not limited thereto.

The conductive film of the present application comprises a first resin layer and a second resin layer on both sides of a base film. The second resin layer is formed on a surface of the base film on which the first resin layer is not formed. The term " resin layer " in the present application means a layer containing at least 15% of a resin component, and may mean a layer having appropriate rigidity and having a predetermined refractive index.

The thermal expansion coefficient of the conductive film of the present application can be determined depending on the physical properties of the first resin layer and the second resin layer. In one example, the first resin layer may function to reduce the thermal expansion coefficient of the conductive film to 15 ppm / ° C or less by adjusting the thickness range while adding the inorganic particles in a predetermined amount.

The first resin layer may include, for example, inorganic particles. The inorganic particles may be one for adjusting the refractive index to a range similar to that of the base film as described above, and impart appropriate stiffness to the first resin layer.

In one example, the inorganic particles include, but are not limited to, ZnO, TiO ₂ , CeO ₂ , SiO ₂ , SnO ₂ , ZrO ₂ , MgO, or Ta ₂ O ₅ .

The first resin layer may contain, for example, the inorganic particles in an amount of 60 wt% or more. The first resin layer within the above-mentioned weight range can provide a conductive film having desired refractive index and rigidity and ultimately improved pattern visibility. The content of the inorganic particles may be, for example, a value calculated using a thermogravimetric analyzer (TGA).

In another example, the inorganic particles may be included in the first resin layer in a range of 70 wt% or more, 80 wt% or more, or 85 wt% or more. The upper limit value of the inorganic particle content range is not particularly limited, but may be, for example, 99 wt% or less, 95 wt% or less, or 90 wt% or less.

By including the inorganic particles in the same range as described above, the first resin layer can exhibit a refractive index similar to that of the base film.

In one example, the absolute value of the difference between the refractive index (based on a wavelength of 550 nm) of the first resin layer and the refractive index (based on a wavelength of 550 nm) of the base film may be 0.3 or less. The desired optical properties of the conductive film can be achieved within the refractive index difference as described above. In another example, the absolute value of the difference between the refractive index (based on a wavelength of 550 nm) of the first resin layer and the refractive index (based on a wavelength of 550 nm) of the base film may be 0.2 or less or 0.1 or less.

Specifically, the refractive index of the first resin layer measured at a wavelength of 550 nm may be in the range of 1.5 to 1.8. In another example, the first resin layer may have a refractive index, measured at a wavelength of 550 nm, in the range of 1.5 to 1.7 or 1.6 to 1.7.

The thickness of the first resin layer may be in the range of, for example, 0.8 μm to 1.5 μm. The thickness of the first resin layer is a factor that can control the coefficient of thermal expansion of the conductive film. If the thickness is excessively thin, the coefficient of thermal expansion may be lowered and pattern pressing may occur. If the thickness is excessively thick, And a crack or the like may occur depending on the subsequent heat treatment process, so that an appropriate thickness should be set within the above numerical range.

The second resin layer of the present application has a difference in a predetermined thickness range and a difference in thermal expansion coefficient from, for example, the first resin layer, thereby imparting overall rigidity to the conductive film, To prevent the conductive film from curving in the direction of the surface of the conductive film.

In one example, the ratio (T1 / T2) of the thickness (T1) of the first resin layer and the thickness (T2) of the second resin layer may be in the range of 0.75 to 1.30. It is possible to improve the pressing phenomenon of the pattern portion of the conductive film within such a thickness ratio range. In another example, the ratio T1 / T2 may be in the range of 0.8 to 1.2 or 0.9 to 1.1, and preferably the low heat of the conductive film when the ratio T1 / T2 is in the range of 0.9 to 1.1. The pressing force of the pattern can be minimized due to the expansion coefficient.

If the ratio (T1 / T2) of the thickness (T1) of the first resin layer and the thickness (T2) of the second resin layer is less than 0.75 or more than 1.30, a problem of visibility of the pattern may be caused.

The thickness of the second resin layer may be suitably set in a range that satisfies the thickness ratio with the first resin layer, and may be in the range of, for example, 0.8 탆 to 1.5 탆.

The first resin layer and the second resin layer may be, for example, a coating layer formed by polymerization of a radically polymerizable compound.

In one example, the first resin layer and the second resin layer may comprise polymerized units of a radically polymerizable compound, for example, a monofunctional or polyfunctional (meth) acrylate compound. The term " monofunctional or polyfunctional (meth) acrylate compound " means a (meth) acrylate monomer, oligomer or mixture thereof containing one or more polymerizable functional groups such as acryloyl group or methacryloyl group . ≪ / RTI > In addition, the above "(meth) acrylate" may mean acrylate or methacrylate.

In one example, the monofunctional (meth) acrylate compound may be an alkyl (meth) acrylate.

Specifically, the alkyl (meth) acrylate may be an alkyl (meth) acrylate having an alkyl group having 1 to 20 carbon atoms, examples of which include methyl (meth) acrylate, ethyl (meth) (Meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, t- (Meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, isononyl (meth) acrylate, (Meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate, tridecyl (meth) acrylate, Acrylic Although the agent or the like can be illustrated, without being limited thereto.

Examples of the polyfunctional (meth) acrylate compound include 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) , Neopentylglycol adipate di (meth) acrylate, hydroxyl puivalic acid neopentyl glycol di (meth) acrylate, dicyclopentanyl (meth) acrylate, ) Di (meth) acrylate, caprolactone modified dicyclopentenyl di (meth) acrylate, ethylene oxide modified di (meth) acrylate, di (meth) acryloxyethyl isocyanurate, allyl Acrylate, trimethylolpropane dimethacrylate, cyclohexyl di (meth) acrylate, tricyclodecane dimethanol (meth) acrylate, dimethylol dicyclopentanedi (meth) acrylate, ethylene oxide modified hexahydrophthalic acid di Di (meth) acrylate, neopentyl glycol-modified trimethylpropane di (meth) acrylate, adamantane di (meth) acrylate or 9,9-bis [4- Bifunctional (meth) acrylates such as acryloyloxyethoxy) phenyl] fluorine and the like; (Meth) acrylates such as trimethylolpropane tri (meth) acrylate, dipentaerythritol tri (meth) acrylate, propionic acid modified dipentaerythritol tri (meth) acrylate, pentaerythritol tri Trifunctional (meth) acrylates such as modified trimethylolpropane tri (meth) acrylate, trifunctional urethane (meth) acrylate or tris (meth) acryloxyethylisocyanurate; Tetrafunctional (meth) acrylates such as diglycerin tetra (meth) acrylate or pentaerythritol tetra (meth) acrylate; Pentafunctional (meth) acrylate such as propionic acid-modified dipentaerythritol penta (meth) acrylate; Caprolactone-modified dipentaerythritol hexa (meth) acrylate or urethane (meth) acrylate (e.g., a reaction product of an isocyanate monomer or trimethylolpropane tri (meth) acrylate) (Meth) acrylate and the like can be used.

Examples of the polyfunctional (meth) acrylate include urethane (meth) acrylate, epoxy (meth) acrylate, polyester (meth) acrylate or polyether Methacrylate) can also be used.

In the present application, the first resin layer and the second resin layer may be formed by selecting one kind or more than one kind of the appropriate kind among the above-mentioned radical polymerizing compounds.

 As described above, the first resin layer and the second resin layer have appropriate rigidity and can play a role of lowering the thermal expansion coefficient of the conductive film.

In one example, the conductive film of the present application may have a thermal expansion coefficient of 15 ppm / DEG C or less. In another example, the conductive film may have a thermal expansion coefficient of 14 ppm / ° C or less, 13 ppm / ° C or less, 12 ppm / ° C or less, or 11 ppm / The lower limit of the lower limit is not particularly limited. For example, the lower limit is 1 ppm / ° C or higher, 2 ppm / ° C or higher, 3 ppm / Or 5 ppm / [deg.] C or higher. The coefficient of thermal expansion can be calculated, for example, by using a thermo mechanical analyzer (TMA) at a rate of 10 占 폚 / min at a temperature range of 25 占 폚 to 150 占 폚, and calculating an average thermal expansion coefficient as a coefficient of linear thermal expansion Lt; / RTI >

The conductive film of the present application is formed by forming the first resin layer and the second resin layer on both surfaces of the base film as described above to maintain the thermal expansion coefficient at 15 ppm / The visibility problem caused by the phenomenon can be overcome.

The conductive film of the present application may further include a conductive layer on the first resin layer. The fact that the conductive layer is included in the first resin layer means not only the case where the conductive layer is in direct contact with the first resin layer but also the case where the conductive layer is included in a state in which an arbitrary layer is further present in the first resin layer .

 The conductive layer may be a structure including a pattern portion and a non-pattern portion through, for example, an etching process.

The material of the conductive layer is not particularly limited and may be, for example, indium tin oxide (ITO) containing gold, silver, platinum, palladium, copper, titanium oxide, cadmium oxide, copper iodide, tin, A metal oxide of at least one metal selected from the group consisting of tin oxide, fluorinated tin oxide (FTO) and zinc oxide; Carbon nanotubes; Metal nanowires formed of a material such as silver or copper; Or a conductive polymer such as a polythiophene-based polymer or a polyaniline-based polymer including poly (styrenesulfonate) (poly (styrenesulfonate)).

The conductive layer may have a refractive index, for example, at a wavelength of 550 nm of 1.9 to 2.1.

The conductive layer may be formed to have a thickness in the range of 0.01 to 0.022 mu m. When the thickness of the conductive layer is less than 0.01 mu m, the conductivity is deteriorated. When the thickness exceeds 0.022 mu m, the transparency may be lowered.

The conductive film of the present application may further include an undercoat layer. The undercoat layer may be located, for example, between the first resin layer and the conductive layer.

2, the conductive film of the present application includes a conductive layer 100 including a pattern portion 101 and a non-pattern portion 102, an undercoat layer 200, a first resin layer 300 ), A base film (400) and a second resin layer (500).

The undercoat layer is located, for example, between the conductive layer and the first resin layer, and has a predetermined refractive index, and may reduce the reflectivity of the conductive film.

The undercoat layer may have a refractive index of, for example, within a range of 1.4 to 1.7 at a wavelength of 550 nm, but the present invention is not limited thereto, and the range may vary depending on the refractive index of the conductive layer and the first resin layer.

The undercoat layer may be an organic layer, an inorganic layer, or an organic-inorganic composite layer formed of, for example, an organic material, an inorganic material, or a composite thereof.

As the organic material, for example, a resin made of an organic material capable of being thermally or UV-curable can be used. Specifically, an acrylic type, an epoxy type, a urethane type, a thiourethane type, an alkyd type resin or a siloxane type polymer can be exemplified.

Examples of the inorganic material include CaF ₂ , BaF ₂ , SiO ₂ , LaF ₃ , CeF ₃ , Al ₂ O ₃ , silicon oxynitride, and aluminum oxynitride.

The organic-inorganic composite may be an acrylic-based, epoxy-based, or organic-based composite containing high refractive index particles of a single composition or composite composition such as TiO ₂ , Nb ₂ O ₅ , Ta ₂ O ₅ , Sb ₂ O ₅ , ZrO ₂ , ZnO, Urethane type, thiourethane type, melamine, alkyd resin, siloxane type polymer, and an organosilane compound represented by the following general formula (1). In this case, when an organosilane compound is used, refractive index control and crosslinking should be possible by mixing with high refractive index particles.

[Chemical Formula 1]

(R ¹ ) _m -Si-X _(4-m)

Wherein R ¹ may be the same or different and is selected from the group consisting of alkyl, alkenyl, alkynyl, aryl, arylalkyl, alkylaryl, arylalkenyl, alkenylaryl, arylalkynyl, alkynylaryl, Wherein R is selected from the group consisting of halogen, substituted amino, amide, aldehyde, keto, alkylcarbonyl, carboxy, mercapto, cyano, hydroxy, alkoxy of 1 to 12 carbons, alkoxycarbonyl of 1 to 12 carbons, sulfonic acid, , Methacryloxy, epoxy or vinyl group,

X may be the same or different from each other and is selected from the group consisting of hydrogen, halogen, alkoxy of 1 to 12 carbon atoms, acyloxy, alkylcarbonyl, alkoxycarbonyl, or -N (R ² ) ₂ (wherein R ² is H, and the 12-alkyl), wherein oxygen or -NR ² (where R ² is a H, or alkyl having 1 to 12 carbon atoms) is inserted between the radicals R ¹ and _{^{Si - (R 1) m -O}} -Si-X ( _4-m) or (R ¹ ) _m -NR ² -Si-X _(4-m) , and m is an integer of 1 to 3.

Examples of the organosilane include methyltrimethoxysilane, methyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxy A silane coupling agent such as silane, phenyl dimethoxy silane, phenyl diethoxy silane, methyl dimethoxy silane, methyl diethoxy silane, phenyl methyl dimethoxy silane, phenyl methyl diethoxy silane, trimethyl methoxy silane, Triphenylmethoxysilane, diphenylmethoxysilane, phenyldimethylethoxysilane, diphenylmethylmethoxysilane, diphenylmethylethoxysilane, dimethylethoxysilane, dimethylethoxysilane, diphenylmethoxysilane, diphenylmethoxysilane, diphenylmethoxysilane, Aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, p-aminophenylsilane, allyltrimethoxysilane, n- (2-aminoethyl) Methoxysilane, 3-amine Propyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-glycidoxypropyldiisopropylethoxysilane, (3-glycidoxypropyl) methyldiethoxysilane, 3- glycidoxypropyltrimethoxy Silane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyl Trimethoxysilane, n-phenylaminopropyltrimethoxysilane, vinylmethyldiethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, and the like.

The organic-inorganic composite may also include a compound represented by the following general formula (2), alone or in combination of two or more thereof.

(2)

M- (R ₃₎ z

In Formula 2, M represents at least one metal selected from the group consisting of aluminum, zirconium and titanium, and R ₃ may be the same or different from each other and is halogen, alkyl having 1 to 12 carbon atoms, And z is an integer of 3 or 4.

When the organic-inorganic hybrid layer is used as the undercoat layer, the content of the organic material may be 1 to 99.99% by weight, specifically 5% by weight or more. In addition, the content of the inorganic material may be 0.01 to 99 wt%, specifically, less than 95 wt%.

The undercoat layer may be a single layer or a multilayer structure of two or more layers.

In one example, the undercoat layer may be a single layer or multi-layer structure formed by wet coating such as spin coating, dip coating or spray coating, as usual.

In another example, the undercoat layer may be a single layer or a multi-layer structure formed by depositing the above-described organic, inorganic or organic-inorganic composite.

The present application also relates to a method for producing a conductive film.

In one example, the present application relates to a method for producing a conductive film comprising a step of forming a first resin layer and a second resin layer on both sides of a base film, and a thermal expansion coefficient of 15 ppm / 占 폚 or less.

The method for manufacturing a conductive film according to the present application is characterized in that a first resin layer and a second resin layer are formed on both surfaces of a base film to adjust the thermal expansion coefficient of the conductive film to a predetermined range or less, It is possible to provide a conductive film with improved pattern visibility by preventing bending phenomenon, improving the rigidity of the first resin layer, and ensuring optical characteristics by having a refractive index similar to that of the base film.

A manufacturing method of a conductive film according to the present application includes a step of forming a first resin layer on a base film.

The method of forming the first resin layer may include, for example, coating the composition for forming the first resin layer on the base film using a known coating method and then curing the coating.

In one example, the first resin layer is formed by applying a composition for forming the first resin layer, which includes, for example, the above-described monofunctional or polyfunctional (meth) acrylate compound, inorganic particles, Coating method using a coating method such as gravure coating, micro gravure coating, slot die coating, spin coating, spray coating, roll coating, bar coating or dip coating, and then curing have.

As the initiator contained in the composition for forming the first resin layer, for example, benzoin, hydroxy ketone, amino ketone or phosphine oxide photoinitiators may be used as the radical photoinitiator.

Specific examples of the radical photoinitiator include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin n-butyl ether, benzoin isobutyl ether, acetophenone, dimethylaminoacetophenone, 2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1- hydroxycyclohexyl phenyl ketone Propane-1-one, 4- (2-hydroxyethoxy) phenyl-2- (hydroxy-2- propyl) Ketone, benzophenone, p-phenylbenzophenone, 4,4'-diethylaminobenzophenone, dichlorobenzophenone, 2-methyl anthraquinone, 2-ethyl anthraquinone, 2- Quinone, 2-methylthioxanthone, 2-ethylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, benzyldimethylketal, acetophenone dimethylketal, p - dimethylaminone (2-hydroxy-2-methyl-1- [4- (1-methylvinyl) phenyl] propanone] or 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide But is not limited thereto.

The content of the initiator can be adjusted within a range suitable for polymerizing the monofunctional or polyfunctional (meth) acrylate compound contained in the composition for forming the first resin layer, for example, in the range of 0.05 to 3 parts by weight But the present invention is not limited thereto.

The solvent contained in the composition for forming the first resin layer may be, for example, water, an organic solvent, or a mixture thereof.

The organic solvent may be, for example, an alcohol solvent, a halogen-containing hydrocarbon solvent, a ketone solvent, a cellosolve solvent or an amide solvent.

More specifically, the alcohol solvent is methanol, ethanol, isopropyl alcohol, n-butanol or diacetone alcohol, and the halogen-containing hydrocarbon solvent is chloroform, dichloromethane or ethylene dichloride. The ketone solvent is acetaldehyde, acetone, Ketone, or methyl isobutyl ketone, and the cellosolve solvent may be methyl cellosolve or isopropyl cellosolve, and the amide solvent may be dimethyl formamide, formamide or acetamide.

The composition for forming the first resin layer may contain, for example, 60 wt% or more of inorganic particles relative to the total solid content. In another example, the inorganic particles may be contained in an amount of 70 wt% or more, 80 wt% or more, or 85 wt% or more based on the total solid content of the composition for forming the first resin layer. The upper limit value of the inorganic particle content range is not particularly limited, but may be, for example, 99 wt% or less, 95 wt% or less, or 90 wt% or less. By including the inorganic particles in the same range as described above, the first resin layer can exhibit a refractive index similar to that of the base film, and can have appropriate rigidity.

That is, the first resin layer of the method for producing a conductive film according to the present application may be formed by coating a composition for forming a first resin layer containing inorganic particles in an amount of 60% by weight or more based on the total solid content, on a base film.

In one example, the difference in refractive index measured at a wavelength of 550 nm between the first resin layer formed from the composition for forming a first resin layer and the base film may be 0.3 or less.

The composition for forming the first resin layer of the present application may further contain known additives in addition to the above components such as a surfactant, a plasticizer, a surface lubricant, a leveling agent, an antioxidant, a corrosion inhibitor, a light stabilizer, Or a silane coupling agent, and the like. The content of the components may be appropriately added within a range that does not impair the properties of the conductive film, and may be included in the range of 0.01 to 2 parts by weight, for example, 100 parts by weight of the composition for forming the first resin layer.

The method of curing the first resin layer is not particularly limited and includes, for example, a method of irradiating a curable (UV) light or the like under a condition that a monofunctional or polyfunctional (meth) acrylate compound can be polymerized by an initiator However, the present invention is not limited thereto.

The first resin layer that is coated and cured may have a thickness in the range of 0.8 mu m to 1.5 mu m. The desired rigidity of the first resin layer can be achieved within the above-mentioned thickness range, and the difference in refractive index between the base film and the base film can be represented by a difference of not more than 0.3 at a wavelength of 550 nm including the inorganic particles in a predetermined range.

The method for producing a conductive film of the present application may include a step of forming a second resin layer on a surface of the base film on which the first resin layer is not formed.

The material and method of forming the second resin layer may be similar to the material and method of forming the first resin layer described above.

In one example, the second resin layer comprises a composition for forming a second resin layer comprising the above-mentioned monofunctional or polyfunctional (meth) acrylate compound, an initiator and a solvent, in a state where the first resin layer of the base film is not formed Coating the surface, and then curing it.

The second resin layer thus formed together with the first resin layer imparts appropriate stiffness to the conductive film and has a predetermined thickness range with the first resin layer to prevent the pressing phenomenon of the pattern according to the heat treatment process Can play a role. The physical properties of the second resin layer formed by the above method, for example, the thickness range with respect to the first resin layer, and the like are the same as those mentioned in the above-mentioned conductive film.

The conductive film formed by the method for producing a conductive film according to the present application may have a thermal expansion coefficient of, for example, 15 ppm / ° C or less. In another example, the conductive film may have a thermal expansion coefficient of 14 ppm / ° C or less, 13 ppm / ° C or less, 12 ppm / ° C or less, or 11 ppm / ° C or less. The lower limit of the lower limit is not particularly limited. For example, the lower limit is 1 ppm / ° C or higher, 2 ppm / ° C or higher, 3 ppm / Or 5 ppm / [deg.] C or higher.

The method for producing a conductive film according to the present application may further include the step of forming an undercoat layer on the first resin layer. The material for forming the undercoat layer is as described above, and a known wet or dry coating method can be used without any limitations.

The method for manufacturing a conductive film according to the present application may further include a step of forming a conductive layer on the undercoat layer and then subjecting the conductive layer to heat treatment.

The method for forming the conductive layer may include, for example, a step of depositing the above-described conductive layer forming material by a method such as sputtering, but is not limited thereto. Methods for forming a conductive layer are known in the art and can be used without limitation in the present application.

The step of heat-treating the conductive film on which the conductive layer is formed is not particularly limited. For example, the conductive layer may be crystallized, or the conductive layer may be patterned and then subjected to additional heat treatment to improve the durability of the film. . ≪ / RTI > In one example, the heat treatment process may be a curing process of photosensitive Ag for 60 minutes at a temperature of 150 < 0 > C.

The conductive film formed by the method for producing a conductive film according to the present application minimizes the bending phenomenon of the portion where the conductive layer is patterned even after the heat treatment process as described above and can solve the visibility problem.

The present application also relates to a touch panel including a conductive film. The conductive film of the present application may be useful as an upper substrate and / or a lower substrate of a touch panel, particularly a resistive touch panel. When the upper panel is pressed with a finger or a pen, the conductive film of the resistive film type is bent and the conductive layer of the upper substrate and the lower substrate are brought into contact with each other So that it can be a structure for detecting the position.

The conductive film according to the present application can realize a touch panel which is improved in visibility, excellent in transparency, and can be manufactured at an economical cost.

The touch panel may be mounted on a display device such as an LCD, PDP, LED, OLED or E-paper, but is not limited thereto.

Hereinafter, the conductive film according to the present application will be described in more detail with reference to Examples and Comparative Examples. However, the following Examples and Comparative Examples are merely examples according to the present application and do not limit the technical idea of the present application. It will be apparent to those of ordinary skill in the art.

The physical properties of the conductive film according to the present application were measured by the following method.

1. Measurement of thermal expansion coefficient of conductive film

The average thermal expansion coefficient measured by cooling and heating the conductive film at a rate of 10 占 폚 / min in a temperature range of 25 占 폚 to 150 占 폚 using a TMA (thermo mechanical analyzer) was calculated as a coefficient of linear thermal expansion.

[ Example  One]

1st  Preparation of Composition (A1) for Resin Layer Formation

Dipentaerythritol hexaacrylate (DPHA), inorganic particles (ZrO ₂ ) and initiator (Irgacure 184) were mixed at a ratio of 40: 60: 3 and a solvent (Methyl isobutyl ketone, MIBK) A composition A1 for forming a first resin layer having a particle content of 60 wt% and a refractive index of about 1.65 was prepared.

Second  Preparation of Composition (A2) for Resin Layer Formation

A composition for forming a second resin layer (A2) having a refractive index of about 1.52 was prepared by mixing a radical polymerizable acrylate (DPHA) and an initiator (Irgacure 184) in a ratio of 100: 3 and adding a solvent (Methyl isobutyl ketone, MIBK) ).

Preparation of conductive film

The first resin layer-forming composition (A1) was coated on one side of a PET base film (UH-13 PET, refractive index of about 1.65) having a thickness of 50 탆 on both sides and subjected to releasing treatment and irradiated with ultraviolet rays to obtain a first (A2) was coated on the surface of the PET base film (UH-13 PET) on which the first resin layer was not formed and irradiated with ultraviolet rays to form a resin layer having a thickness of about 1.3 탆 Of the second resin layer. Thereafter, a composition (A3) for forming an undercoat layer containing an epoxy resin and propylene glycol monomethyl ether (PGME) was coated on the first resin layer, ) And an undercoat layer having a thickness of about 30 nm were formed. ITO was deposited on the undercoat layer by a vacuum sputtering method. Then, the ITO conductive layer was patterned and an Ag photosensitive curing process was performed at 150 ° C for 1 hour to sequentially form a second resin layer / substrate film / 1 > resin layer / undercoat layer / conductive layer. The physical properties and the pattern visibility evaluation results of the conductive film of Example 1 are shown in Table 1 below.

[ Example  2]

(Dipentaerythritol hexaacrylate, DPHA), inorganic particles (ZrO ₂ , etc.) were used in place of the first resin layer- And SiO ₂ ) and an initiator (Irgacure 184) in a weight ratio of 20: 80: 3 to prepare a composition (A4) for forming a first resin layer having an inorganic particle content of 80 wt% based on the total solid content, A conductive film was prepared in the same manner as in Example 1, except that the first resin layer having a thickness of about 1.0 탆 was formed using the composition (A4) The physical properties and the pattern visibility evaluation results of the conductive film of Example 2 are shown in Table 1 below.

[ Example  3]

A conductive film was prepared in the same manner as in Example 2, except that the thickness of the first resin layer was about 1.3 탆. The physical properties and the pattern visibility evaluation results of the conductive film of Example 3 are shown in Table 1 below.

[ Comparative Example  One]

A conductive film was formed in the same manner as in Example 1, except that the first resin layer was not formed. The physical properties and the pattern visibility evaluation results of the conductive film of Comparative Example 1 are shown in Table 1 below.

[ Comparative Example  2]

A conductive film was formed in the same manner as in Example 1, except that the second resin layer was not formed. The physical properties and the pattern visibility evaluation results of the conductive film of Comparative Example 2 are shown in Table 1 below.

[ Comparative Example  3]

(Dipentaerythritol hexaacrylate, DPHA), inorganic particles (ZrO ₂ ) and an initiator (Irgacure 184) were mixed in a weight ratio of 50: 50: 3 to obtain a first water dispersion having an inorganic particle content of 50 wt% A conductive film was produced in the same manner as in Example 1, except that the composition for forming a ground layer (B1) was used. The physical properties and the pattern visibility evaluation results of the conductive film of Comparative Example 3 are shown in Table 1 below.

[ Comparative Example  4]

A conductive film was prepared in the same manner as in Example 1 except that the thickness of the first resin layer was set to about 0.7 탆. The physical properties and the pattern visibility evaluation results of the conductive film of Comparative Example 4 are shown in Table 1 below.

[ Experimental Example ] - Evaluation of pattern visibility

The pattern visibility of the conductive films prepared according to Examples and Comparative Examples was visually evaluated based on the following criteria.

1.0: Excellent pattern visibility

1.5: Excellent pattern visibility

2.0: Good pattern visibility

2.5: poor pattern visibility

3.0: Very bad pattern visibility

As shown in the following Table 1, the conductive films according to the embodiments of the present application have a rigidity with a thermal expansion coefficient of 15 ppm / 占 폚 or less, and are excellent in pattern visibility even after the heat treatment process, It can be confirmed that the thermal expansion coefficient is higher than 15 ppm / DEG C, and the visibility due to the pattern pressing phenomenon is lowered due to the stress caused by the heat treatment process or the like.

Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 The first resin layer Inorganic particle content (kind, content) ZrO ₂ , 60 wt% ZrO ₂ + SiO ₂ , 80 wt% ZrO ₂ + SiO ₂ , 80 wt% - ZrO ₂ , 60 wt% ZrO _2, 50wt% ZrO ₂ , 60 wt% Thickness (㎛) 1.3 1.0 1.3 - 1.3 1.3 0.7 The second resin layer thickness (mu m) 1.3 1.3 1.3 1.3 - 1.3 1.3 Thermal Expansion Coefficient (ppm / ° C) 14.17 13.23 10.31 19.17 Not measurable 19.14 18.02 Pattern visibility evaluation 1.5 1.0 1.0 3.0 Not measurable 2.5 2.5

100: conductive layer
101:
102: Non-patterned portion
200: undercoat layer
300: first resin layer
400: substrate film
500: second resin layer

Claims (14)

A base film;
A first resin layer formed on one surface of the base film; And
And a second resin layer formed on a surface of the base film on which the first resin layer is not formed,
A conductive film having a thermal expansion coefficient of 15 ppm / ° C or lower. The method according to claim 1,
Wherein the thickness of the base film is in the range of 10 탆 to 80 탆. The method according to claim 1,
Wherein the ratio (T1 / T2) of the thickness (T1) of the first resin layer and the thickness (T2) of the second resin layer is in the range of 0.75 to 1.30. The method according to claim 1,
Wherein an absolute value of a difference between a refractive index (based on a wavelength of 550 nm) of the first resin layer and a refractive index (based on a wavelength of 550 nm) of the base film is 0.3 or less. The method according to claim 1,
Wherein the first resin layer comprises inorganic particles. 6. The method of claim 5,
Wherein the ratio of the inorganic particles in the first resin layer is 60% by weight or more. The method according to claim 1,
Wherein the first and second resin layers comprise polymerized units of a monofunctional or polyfunctional (meth) acrylate compound. The method according to claim 1,
A conductive film further comprising a conductive layer on the first resin layer. 9. The method of claim 8,
Wherein the conductive film further comprises an undercoat layer between the first resin layer and the conductive layer. A method for producing a conductive film according to claim 1, comprising the steps of: forming a first resin layer and a second resin layer on both surfaces of a base film. 11. The method of claim 10,
Wherein the first resin layer is formed by coating a resin composition containing 60% by weight or more of inorganic particles on a solid basis. 11. The method of claim 10,
And forming an undercoat layer on the first resin layer. 13. The method of claim 12,
Forming a conductive layer on the undercoat layer, and subjecting the conductive layer to heat treatment. A touch panel comprising the conductive film of claim 1.

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