KR20160146226A - Conductive laminate - Google Patents

Abstract

The present application relates to a conductive laminate and its uses. An appearance and performance of a product to which the conductive laminate is applied is able to be maintained as the conductive laminate of the present application is able to effectively suppress generation of bubbles in a vicinity of a step portion even when attached to a substrate having a difference in surface step. Such a conductive laminate is able to usefully be used in areas such as in touch panels and the like.

Description

Conductive laminate {CONDUCTIVE LAMINATE}

The present application relates to a conductive laminate and its use.

BACKGROUND ART [0002] A touch panel or a touch screen is variously applied to various information processing terminals such as a mobile communication terminal or an ATM, or a display device such as a TV and a monitor. In addition, as the application to small portable electronic devices increases, there is an increasing tendency for a smaller and lighter touch panel or screen.

In constructing the touch panel or the screen, for example, a conductive laminate as disclosed in Patent Document 1 or 2 is used. Such a conductive laminate may include a pressure-sensitive adhesive layer. It is important that the conductive laminate does not generate air bubbles when it is laminated to another substrate through the pressure-sensitive adhesive layer. When bubbles are generated, the design of the screen is remarkably deteriorated, which may affect the appearance and cause deterioration of the performance.

Patent Document 1: Korean Patent Publication No. 2002-0036837 Patent Document 2: Korean Patent Publication No. 2001-0042939

The present application relates to a conductive laminate and its use.

The present application relates to a conductive laminate. Fig. 1 exemplarily shows the structure of the conductive laminate according to the first embodiment of the present application. As shown in Fig. 1, the conductive laminate 1 comprises a base layer 101; And a conductive layer (201) formed on one surface of the base layer; And a pressure-sensitive adhesive layer (30) adhered to a surface of the first base layer on which the first conductive layer is not formed. Hereinafter, the conductive laminate of the present application will be described in detail

[Base layer]

The type of the base layer 101 is not particularly limited, and for example, a glass base material or a plastic base material can be used. As the plastic substrate, a polyester film, a polyamide film, a polyvinyl chloride film, a polystyrene film, or a polyolefin film can be used, and a polyester film such as polyethylene terephthalate, an acrylic resin film or a polycarbonate film can be used But is not limited thereto.

The thickness of the base layer 101 is not particularly limited and may be suitably set as long as it can function as a conductive laminate. For example, the thickness of the substrate layer may be in the range of about 1 탆 to 500 탆, about 3 탆 to 300 탆, about 5 탆 to 250 탆, or about 10 탆 to 200 탆.

The substrate layer 101 may be subjected to appropriate bonding treatment such as, for example, corona discharge treatment, ultraviolet ray irradiation treatment, plasma treatment, or sputter etching treatment, but the present invention is not limited thereto.

[Conductive layer]

The conductive layer 201 may be formed on one surface of the base layer 101. Examples of the material constituting the conductive layer 201 include metals such as gold, silver, platinum, palladium, copper, aluminum, nickel, chromium, titanium, iron, cobalt, tin, Tin oxide, titanium oxide, cadmium oxide, or a mixture of two or more of the above metals, copper iodide, and the like. The conductive layer may be a crystalline layer or an amorphous layer. In one example, indium tin oxide (ITO) may be used as the material of the conductive layer, but the present invention is not limited thereto.

The thickness of the conductive layer 201 may be controlled within a range of about 10 nm to 300 nm, about 10 nm to 200 nm, or about 10 nm to 100 nm in consideration of the possibility of formation of a continuous coating, conductivity, transparency and the like, but is not limited thereto.

The method of forming the conductive layer 201 is not particularly limited, and may be, for example, a vacuum evaporation method, a sputtering method, an ion plating method, a spray pyrolysis method, a chemical plating method, an electroplating method or a general thin film forming method combining two or more of the above methods And can be usually formed by a vacuum vapor deposition method or a sputtering method.

The conductive layer 201 may be formed on one side of the base layer via an anchor layer or a dielectric layer, if necessary. The anchor layer or the dielectric layer improves the adhesion between the conductive layer and the base layer, and improves scratch resistance or flex resistance.

The anchor layer or the dielectric layer may be formed of an inorganic material such as SiO ₂ , MgF ₂ or Al ₂ O ₃ ; A sputtering method, an ion plating method, or a coating method using an organic material such as an acrylic resin, a urethane resin, a melamine resin, an alkyd resin or a siloxane-based polymer, or a mixture of two or more of them. The anchor layer or the dielectric layer may typically be formed to a thickness of about 100 nm or less, specifically, 15 nm to 100 nm or 20 nm to 60 nm.

[Pressure sensitive adhesive layer]

The pressure-sensitive adhesive layer 30 may be attached to a surface of the base layer 101 on which the conductive layer 201 is not formed. And the pressure-sensitive adhesive layer sticking polymer. As used herein, the term " polymer " may refer to a polymer in which one or more different monomers are mixed and polymerized. In one example, the pressure-sensitive adhesive layer may comprise the pressure-sensitive adhesive polymer in a crosslinked state. Hereinafter, the storage elastic modulus or the loss elastic modulus of the pressure-sensitive adhesive layer is referred to, unless otherwise specified, the storage elastic modulus or loss modulus of the pressure-sensitive adhesive layer containing the pressure-sensitive adhesive polymer in a crosslinked state. When the pressure-sensitive adhesive layer is adhered to another substrate having a surface step difference, the physical properties and composition of the pressure-sensitive adhesive layer can be controlled as follows in terms of suppressing the formation of bubbles in the peripheral portion of the step.

The pressure-sensitive adhesive layer (30) has a storage modulus at a temperature of 50 占 폚 and a frequency of 1 rad / sec of 1.0 x 10 ⁴ Pa or less, 0.98 x 10 ⁴ Pa or less, 0.96 x 10 ⁴ Pa or less, 0.94 x 10 ⁴ Pa or less, 0.92 x 10 ⁴ Pa or less, 0.90 x 10 ⁴ Pa or less, 0.80 x 10 ⁴ Pa or less, 0.70 x 10 ⁴ Pa or less, or may be less than 0.60 x 10 ⁴ Pa. The lower limit of the storage elastic modulus at 50 ℃ temperature and 1 rad / sec frequency of the pressure-sensitive adhesive layer 30 is not particularly limited, and for example, may be equal to or greater than 0.1 x 10 ⁴ Pa. The term " storage elastic modulus " as used herein generally means " dynamic storage modulus ". That is, when a sine-shaped shear strain is applied to an elastic body, a stress is delayed in an intermediate form in the case of a viscoelastic material. Mathematically, one component is in the same phase and the other component is delayed by pi / 2 In this case, energy stored in the same phase, that is, the energy stored without loss by elasticity, can be referred to as a " dynamic storage modulus " or " storage modulus ". The storage elastic modulus of the pressure-sensitive adhesive layer can be adjusted within the above-mentioned range, and even when attached to a substrate having a surface step difference, the generation of bubbles in the peripheral portion of the step can be effectively suppressed.

The pressure-sensitive adhesive layer 30 preferably has a loss modulus at a temperature of 50 DEG C and a frequency of 1 rad / sec of not more than 1.0 x 10 ⁴ Pa, not more than 0.98 x 10 ⁴ Pa, not more than 0.96 x 10 ⁴ Pa, ⁴ Pa or less, 0.92 x 10 ⁴ Pa or less, 0.90 x 10 ⁴ Pa or less, 0.80 x 10 ⁴ Pa or less, 0.70 x 10 ⁴ Pa or less, 0.60 x 10 ⁴ Pa or less, or 0.50 x 10 ⁴ Pa or less. A loss modulus at the temperature of 50 ℃ and 1 rad / sec frequency lower limit of the pressure-sensitive adhesive layer 30 is not particularly limited, and for example, may be equal to or greater than 0.1 x 10 ⁴ Pa. As used herein, the term " loss modulus " means " dynamic loss modulus " That is, when sine shear deformation is applied to the elastic body as described above, energy that is irreversibly lost due to the portion shifted by pi / 2, that is, converted to heat due to elasticity is referred to as " dynamic loss elastic modulus &Quot; modulus of elasticity ". It is possible to control the loss elastic modulus of the pressure-sensitive adhesive layer within the above-mentioned range, thereby suppressing the generation of bubbles in the periphery of the step even when attached to a substrate having a surface step difference.

The pressure-sensitive adhesive polymer contained in the pressure-sensitive adhesive layer (30) may include a first monomer unit having an alkyl group of 5 or more carbon atoms and a crosslinking monomer unit. As used herein, the term " monomeric polymerization unit " may refer to a form in which the monomer undergoes a polymerization reaction to form the skeleton of the polymer, for example, a main chain or side chain. In the case where the adhesive polymer includes the above monomeric polymerized units, the pressure-sensitive adhesive layer can exhibit the aforementioned loss or storage modulus range, and even when the pressure-sensitive adhesive layer is adhered to a substrate having a surface step difference, have.

As the first monomer, for example, an alkyl (meth) acrylate having an alkyl group having 5 or more carbon atoms can be used. The alkyl group is not particularly limited when it has 5 or more carbon atoms, but may be, for example, a branched chain or straight chain alkyl group, more preferably a straight chain alkyl group. Examples of the first monomer include monomers such as pentyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, ethylhexyl (meth) acrylate, nonyl Acrylate and the like, and one or more of the above can be used. As an embodiment of the present invention, 2-ethylhexyl (meth) acrylate can be used, but is not limited thereto. The upper limit of the carbon number of the alkyl group of the first monomer is not particularly limited. For example, an alkyl (meth) acrylate having an alkyl group having 20 or less carbon atoms, 18 or less carbon atoms, 16 or less carbon atoms, 14 or less carbon atoms, 12 or less carbon atoms, Can be used.

The first monomeric polymerized units may be included in a ratio of greater than about 50 parts by weight relative to 100 parts by weight of the viscous polymer. In the present specification, the unit " weight part " may mean a ratio of the weight between the respective components. More specifically, the first monomer polymerized units may be present in a proportion of at least about 55 parts by weight, at least 60 parts by weight, at least 65 parts by weight, at least about 70 parts by weight, at least about 75 parts by weight, or at least about 80 parts by weight relative to 100 parts by weight of the viscous polymer May be included in the adhesive polymer. The upper limit of the content ratio of the first monomer polymerized units in the adhesive polymer is not particularly limited, but may be, for example, about 95 parts by weight or less, or about 90 parts by weight or less. In this range, the pressure-sensitive adhesive layer can exhibit the storage or loss elastic modulus range described above, and even when attached to a substrate having a surface step difference, it is possible to effectively suppress the occurrence of bubbles in the peripheral portion of the step.

The tacky polymer may also comprise a crosslinkable monomeric polymerization unit. As used herein, the term " crosslinkable monomer " may mean a monomer capable of providing a crosslinkable functional group to a polymer when the polymer contains a crosslinkable functional group and another functional group capable of forming a tacky polymer.

In the production of pressure-sensitive adhesives, various monomers which can be used as crosslinking monomers are known, and all of these monomers can be used in the adhesive polymer. Examples of the crosslinkable monomer include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl Hydroxyalkyl (meth) acrylates such as acrylate or 8-hydroxyoctyl (meth) acrylate; (Meth) acrylates such as poly (alkylene glycol) (meth) acrylates such as poly (ethylene glycol) (meth) acrylate or poly (propylene glycol) , Carboxyl group-containing copolymerizable monomers such as 3- (meth) acryloyloxypropyl acid, 4- (meth) acryloyloxybutyl acid, acrylic acid doublet, itaconic acid, maleic acid or maleic anhydride But is not limited thereto.

When the tacky polymer contains a crosslinkable monomer, for example, the crosslinkable monomer has a polymerization unit in an amount of 1 to 30 parts by weight, 5 to 30 parts by weight, 10 to 30 parts by weight, 30 parts by weight or 12 parts by weight to 30 parts by weight. In this range, the pressure-sensitive adhesive layer can exhibit the storage or loss elastic modulus range described above, and even when attached to a substrate having a surface step difference, it is possible to effectively suppress the occurrence of bubbles in the peripheral portion of the step.

The tacky polymer may further comprise a second monomer polymerization unit having an alkyl group having 1 to 4 carbon atoms. As the second monomer, for example, alkyl (meth) acrylates having an alkyl group having 1 to 4 carbon atoms can be used. The alkyl group having 1 to 4 carbon atoms is not particularly limited, but may be, for example, a branched chain or straight-chain alkyl group, more preferably a straight-chain alkyl group. Examples of such monomers include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, Butyl (meth) acrylate, sec-butyl (meth) acrylate, and the like can be exemplified. According to one embodiment of the present application, methyl (meth) acrylate can be used but is not limited thereto.

When the tackifier polymer further contains a second monomer polymerized unit, for example, the second monomer polymerized unit may be added in an amount of 1 part by weight to 30 parts by weight, 5 parts by weight to 30 parts by weight, and 10 parts by weight To 30 parts by weight or 12 parts by weight to 30 parts by weight. In this range, the pressure-sensitive adhesive layer can exhibit the storage or loss elastic modulus range described above, and even when attached to a substrate having a surface step difference, it is possible to more effectively suppress the occurrence of bubbles in the peripheral portion of the step.

The method for producing the adhesive polymer is not particularly limited and can be produced in a usual manner. The sticky polymer can be polymerized by, for example, the LRP (Living Radical Polymerization) method, and examples thereof include a method of using an organic rare earth metal complex as a polymerization initiator or using an organic alkali metal compound as a polymerization initiator to form an alkali metal or alkaline earth metal , An anion polymerization method in which an organic alkali metal compound is used as a polymerization initiator and synthesized in the presence of an organoaluminum compound, an anion polymerization method using an atom transfer radical polymerization agent as a polymerization initiator, (ATRP), Atomic Transfer Radical Polymerization (ATRP), and ICAR (Atomization Transfer), which perform polymerization under an organic or inorganic reducing agent that generates electrons using an atom transfer radical polymerization agent as a polymerization initiator. Initiators for continuous activator regeneration) (RAFT) using a reversible addition-cleavage chain transfer agent using an inorganic reductant chain transfer agent, or an organic tellurium compound as an initiator. Among these methods, an appropriate method can be selected and applied have.

The weight average molecular weight of the tacky polymer may be, for example, from 300,000 to 1,000,000, from 300,000 to 900,000, or from 300,000 to 80,000. In this range, the pressure-sensitive adhesive layer can exhibit the storage or loss elastic modulus range described above, and even when attached to a substrate having a surface step difference, it is possible to effectively suppress the occurrence of bubbles in the peripheral portion of the step.

The pressure-sensitive adhesive layer may further include a crosslinking agent capable of crosslinking the pressure-sensitive adhesive polymer. The cross-linking agent includes at least one functional group capable of reacting with the crosslinkable functional group contained in the tacky polymer, and having 1 to 10, 1 to 8, 1 to 6, or 1 to 4 functional groups Crosslinking agents may be used. As such a cross-linking agent, an appropriate type may be selected and used from among conventional cross-linking agents such as an isocyanate cross-linking agent, an epoxy cross-linking agent, an aziridine cross-linking agent or a metal chelate cross-linking agent considering the kind of the cross-linkable functional group of the adhesive polymer.

Examples of the isocyanate crosslinking agent include diisocyanate compounds such as tolylene diisocyanate, xylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, isoboron diisocyanate, tetramethylxylene diisocyanate, and naphthalene diisocyanate; A reaction product such as a polyol such as trimethylol propane or an isocyanurate adduct of the above diisocyanate compound. Of these, xylene diisocyanate or hexamethylene diisocyanate can be preferably used. As the epoxy crosslinking agent, , Ethylene glycol diglycidyl ether, triglycidyl ether, trimethylol propane triglycidyl ether, N, N, N ', N'-tetraglycidyl ethylenediamine and glycerin diglycidyl ether. It is at least one selected from can be illustrated.

Aziridine crosslinking agents include N, N'-toluene-2,4-bis (1-aziridinecarboxamide), N, N'-diphenylmethane-4,4'-bis (1-aziridinecarboxamide ), Triethylene melamine, bisisoproparyl-1- (2-methyl aziridine), or tri-1-aziridinyl phosphine oxide, but the present invention is not limited thereto. The metal chelate crosslinking agent A compound in which a polyvalent metal such as aluminum, iron, zinc, tin, titanium, antimony, magnesium and / or vanadium is coordinated to acetylacetone or ethyl acetoacetate, and the like.

The crosslinking agent may be contained in an amount of, for example, 0.01 to 10 parts by weight, 0.015 to 5 parts by weight, 0.02 to 2.5 parts by weight or 0.025 to 1 part by weight based on 100 parts by weight of the adhesive polymer. The cross-linking agent may be adjusted to be included in the tacky polymer in the above-mentioned range so that the aforementioned storage or loss elastic modulus is formed within a desired range.

The pressure-sensitive adhesive layer may further include a silane coupling agent. As the silane coupling agent, for example, a silane coupling agent having a beta-cyano group or an acetoacetyl group can be used. Such a silane coupling agent can make the pressure-sensitive adhesive formed by, for example, a polymer having a low molecular weight exhibit excellent adhesion and adhesion stability. When the pressure-sensitive adhesive layer further comprises a silane coupling agent, the silane coupling agent may be included in an amount of 0.01 to 5 parts by weight or 0.01 to 1 part by weight based on 100 parts by weight of the pressure-sensitive adhesive polymer.

The pressure-sensitive adhesive layer may further include a tackifier if necessary. Examples of the tackifier include a hydrocarbon resin or hydrogenated product thereof, a rosin resin or hydrogenated product thereof, a rosin ester resin or hydrogenated product thereof, a terpene resin or hydrogenated product thereof, a terpene phenol resin or hydrogenated product thereof, Polymerized rosin ester resin, and the like, or a mixture of two or more of them may be used, but the present invention is not limited thereto. The tackifier may be included in the pressure-sensitive adhesive composition in an amount of 100 parts by weight or less based on 100 parts by weight of the tacky polymer.

The pressure-sensitive adhesive layer may further include, if necessary, at least one additive selected from the group consisting of a curing agent, a UV stabilizer, an antioxidant, a colorant, a reinforcing agent, a filler, a defoamer, a surfactant and a plasticizer.

The method for producing the pressure-sensitive adhesive layer is not particularly limited, and can be produced in a usual manner. For example, a pressure-sensitive adhesive composition in which a pressure-sensitive adhesive polymer is present in a crosslinked state can be prepared by applying the pressure-sensitive adhesive composition to an appropriate process substrate by conventional means and curing the pressure-sensitive adhesive composition. In the present application, it is preferable that the curing process is performed after sufficiently removing bubble-inducing components such as volatile components or reaction residues contained in the pressure-sensitive adhesive composition. Accordingly, the crosslinking density or the molecular weight of the pressure-sensitive adhesive is too low to lower the elastic modulus, and bubbles existing in the pressure-sensitive adhesive interface at high temperature are increased to form a scattering body therein. The method of curing the pressure-sensitive adhesive composition is not particularly limited. For example, the pressure-sensitive adhesive composition may be cured by suitable heating, drying and / or aging processes or by curing by electromagnetic wave irradiation such as ultraviolet .

[Second base layer and second conductive layer]

The conductive laminate may further include a second base layer and a second conductive layer. Hereinafter, the above-described base layer and conductive layer are referred to as a first base layer and a first conductive layer, respectively, for the purpose of classification. Fig. 2 exemplarily shows the structure of the conductive laminate 2 according to the second embodiment of the present application. As shown in Fig. 2, the conductive laminate 2 comprises a first base layer 101; A first conductive layer 201 formed on one surface of the first base layer 101; And a pressure-sensitive adhesive layer (30) adhered to a surface of the first base layer on which the first conductive layer is not formed. The conductive laminate 2 includes a second conductive layer 202 formed on one surface of the second base layer 102 and the second base layer 102 and having a surface level difference 2021. The surface of the first base layer 101 on which the first conductive layer is not formed and the surface of the second conductive layer 202 having a step difference may exist in the state of being adhered by the adhesive layer 30 have.

As used herein, the term " surface step " may mean the difference in height of the surface (shown as H in Fig. 2). The step difference of the surface of the second conductive layer may be derived, for example, from a pattern electrode used in a touch panel to be described later. The pattern shape of the pattern electrode is not particularly limited and may be, for example, a mesh shape or a shape in which electrodes having a polygonal or circular cross-section are spaced apart from each other. The material of the pattern electrode is not particularly limited and may be any one of silver (Ag), aluminum (Al), copper (Cu), chromium (Cr), nickel (Ni), molybdenum . ≪ / RTI > In another example, the step difference of the surface of the second conductive layer may be printed printed steps, for example, to improve the design of the screen.

The thickness of the surface step of the second conductive layer is not particularly limited and can be appropriately selected according to the application to which the structure causing the surface step difference is applied, but it may be usually within the range of about 1 to 150 [mu] m. The thickness range of the pressure-sensitive adhesive layer is not particularly limited, but may be within the range of, for example, 15 μm to 30 μm. In another example, the thickness of the pressure-sensitive adhesive layer may have a thickness range of greater than about 2 占 퐉, for example, as compared with the thickness of the surface step difference. When the thickness of the pressure-sensitive adhesive layer 30 is within the above-mentioned range, generation of bubbles can be effectively reduced in the peripheral portion of the surface step of the second conductive layer (indicated by A in Fig. 2).

The conductive laminate includes the above-described base layer, conductive layer and pressure-sensitive adhesive layer as basic units, and if necessary, other elements usually used for forming the conductive laminate, such as a transparent sheet layer, a release film layer or a hard coating layer May be further included.

The present application also relates to the use of the conductive laminate. The conductive laminate of the present application can be used, for example, in the configuration of a touch panel. The touch panel may include the conductive laminate as an electrode plate for a touch panel, for example. Further, the above-described pattern electrode can function as a touch sensor. The touch panel may have a known structure including an electrostatic capacity type or a resistance film type as long as the touch panel includes the conductive laminated body. The conductive laminate can be used for forming various devices such as a liquid crystal display as well as a touch panel.

Since the conductive laminate of the present application can suppress the generation of bubbles in the vicinity of the step portion even when attached to a substrate having a surface step difference, the appearance and performance of the product to which the conductive laminate is applied can be maintained. Such a conductive laminate can be usefully used, for example, in touch panels and the like.

1 is a schematic view of a conductive laminate according to the first embodiment of the present application.
2 is a schematic view of the conductive laminate of the second embodiment of the present application.

Hereinafter, the present application will be described in more detail by way of examples according to the present application and comparative examples not complying with the present application, but the scope of the present application is not limited by the following embodiments.

The physical properties in the following examples and comparative examples were evaluated in the following manner.

1. Molecular weight measurement

The weight average molecular weight (Mw) was measured using GPC under the following conditions, and the measurement results were converted using standard polystyrene of Agilent system for the calibration curve.

<Measurement Conditions>

Measuring instrument: Agilent GPC (Agilent 1200 series, U.S.)

Column: Two PL Mixed B connections

Column temperature: 40 ° C

Eluent: THF (Tetrahydrofuran)

Flow rate: 1.0 mL / min

Concentration: ~ 1 mg / mL (100 μL injection)

2. Evaluation of storage modulus

The pressure-sensitive adhesive composition prepared in Examples and Comparative Examples was coated between release films and cut to a size of 15 cm x 25 cm. The release film on one side was removed and laminated five times to have a thickness of about 1 mm. Subsequently, the laminate was cut into a circular shape having a diameter of 8 mm, compressed using glass, and allowed to stand overnight to improve wetting at the interface between the respective layers, To prepare a sample. Then, the sample was placed on a parallel plate, the gap was adjusted, the zero point of Normal & Torque was set, and the normal force was stabilized. Then, the storage elastic modulus was measured.

Measuring instruments and measuring conditions

Measuring instrument: ARES-RDA, TA Instruments Inc. with forced convection oven.

Measuring conditions:

geometry: 8 mm parallel plate

Thickness: about 1 mm

test type: dynamic strain frequency sweep

Strain = 10.0 [%], Temperature: 50 [deg.] C

Initial frequency: 0.1 rad / s, Final frequency: 1 rad / s

3. Step  Evaluation of characteristics (1)

A transparent conductive laminate having an ITO layer (width x length = 10 cm x 10 cm thickness: 20 nm) formed on a PET film (width x length = 10 cm x 10 cm thickness: Ag paste (width x length = 1 cm x 10 cm, thickness: 18 um) was applied on the ITO layer of the heat-treated transparent conductive laminate, and then heat-treated in an oven at about 150 ° C for about 30 minutes. Next, the adhesive layer of the conductive laminate produced in Examples and Comparative Examples was applied so as to be in contact with the surface of the transparent conductive laminate on which the Ag paste was formed, and then bubbles were observed on the periphery of the steps through an optical microscope.

O: No air bubbles were observed.

B: Fine bubbles were visually observed

X: Large bubbles were observed with the naked eye

4. Step  Evaluation of characteristics (2)

Evaluation of Step Characteristic The specimen of (1) was heated at 50 ° C for 30 minutes to 6 kgf / cm ² After the autoclave treatment, bubbles were observed on the periphery of the step through an optical microscope.

O: No air bubbles were observed.

B: Fine bubbles were visually observed

X: Large bubbles were observed with the naked eye

Manufacturing example  1. Preparation of adhesive polymer (A1)

80 parts by weight of 2-ethylhexyl acrylate (EHA), 10 parts by weight of methyl acrylate (MA) and 2 parts by weight of 2-hydroxyethyl acrylate (EA) were added to a 1 L reactor equipped with a cooling device, 10 parts by weight of HEA were added. Subsequently, 100 parts by weight of ethyl acetate (EAc) was poured into a solvent, and nitrogen gas was purged for 60 minutes to remove oxygen. Then, while maintaining the temperature at 60 占 폚, azobisisobutyronitrile (AIBN) were added to initiate the reaction. Thereafter, the reaction product which had been reacted for about 5 hours was diluted with ethyl acetate (EAc) to prepare a sticky polymer (A1).

Manufacturing example  2 to Manufacturing example  5. Preparation of sticky polymers (A2 to A3 and B1 to B2)

(A 2 to A 3 and B 1 to B 2) were obtained in the same manner as in Production Example 1, except that raw materials and additives used in the production of the pressure-sensitive adhesive polymer (A1) ).

Raw material EA
V-65
EHA MA BA IBOA HEA
Adhesiveness
polymer A1 80 10 - - 10 100 0.2 A2 90 - - - 10 100 0.15 A3 90 - - - 10 100 0.2 B1 50 40 - - 10 100 0.06 B2 - - 55 30 15 100 0.06 Content Unit: g
BA: n-butyl acrylate
IBOA: isobornyl acrylate
MA: (meth) acrylate
HEA: 2-hydroxyethyl acrylate
EHA: 2-ethylhexyl acrylate
EA: ethyl acetate
V-65: 2,2'-azobis (2,4-dimethyl valeronitrile)

Example  One

Preparation of pressure-sensitive adhesive composition

To 100 parts by weight of the solid content of the adhesive polymer (A1) prepared in Preparation Example 1, 0.25 parts by weight of "Takenate D110N" (xylene diisocyanate) (Mitsui Chemicals, Inc.) as a crosslinking agent was uniformly mixed to prepare a pressure-sensitive adhesive composition.

Conductivity Of the laminate  Produce

On one side of the PET film, the pressure-sensitive adhesive composition was releasably treated with silicone, and the pressure-sensitive adhesive composition thus prepared was coated and cured to a thickness of about 25 탆 to form a pressure-sensitive adhesive layer. Thereafter, the pressure-sensitive adhesive layer was transferred to the opposite surface of a PET film (thickness: about 25 mu m) having an ITO layer formed on one surface thereof in a usual manner, and the PET film thus treated was peeled off to produce a conductive laminate.

Example  2

A pressure-sensitive adhesive composition and a pressure-sensitive adhesive film were prepared in the same manner as in Example 1, except that the pressure-sensitive adhesive polymer contained in the pressure-sensitive adhesive composition of Example 1 was changed to A2.

Example  3

A pressure-sensitive adhesive composition and a pressure-sensitive adhesive film were prepared in the same manner as in Example 1 except that the pressure-sensitive adhesive polymer contained in the pressure-sensitive adhesive composition of Example 1 was changed to A3.

Comparative Example  One

A pressure-sensitive adhesive composition and a pressure-sensitive adhesive film were prepared in the same manner as in Example 1, except that the pressure-sensitive adhesive polymer contained in the pressure-sensitive adhesive composition of Example 1 was charged as B1.

Comparative Example  2

A pressure-sensitive adhesive composition and a pressure-sensitive adhesive film were prepared in the same manner as in Example 1 except that the pressure-sensitive adhesive polymer contained in the pressure-sensitive adhesive composition of Example 1 was charged with B2.

The physical properties and evaluation results of the above-mentioned Examples and Comparative Examples are shown in Table 2 below.

division Example Comparative Example One 2 3 One 2 Molecular weight (unit: million) 56 42 74 110 120 Storage modulus (× 10 ⁴ )
(Unit: pa) 0.9 0.5 0.6 7.7 8.8 Step evaluation (1) △ ○ ○ X X Evaluation of steps (2) ○ ○ ○  X X

As can be seen from the above Table 2, in the case of the conductive laminate of the present application, by having the storage elastic modulus within a specific range, the generation of bubbles in the periphery of the step difference can be effectively suppressed.

101 and 102: First and second substrate layers
201 and 202: second and second conductive layers
2021: Step
30: pressure-sensitive adhesive layer
H: step thickness
A: step periphery

Claims (21)

A first base layer;
A first conductive layer formed on one surface of the first base layer; And
And a pressure-sensitive adhesive layer adhered to a surface of the first base layer on which the first conductive layer is not formed, the pressure-sensitive adhesive layer having a storage elastic modulus at a temperature of 50 ° C and a frequency of 1 rad / sec of 1.0 x 10 ⁴ Pa or less. The method according to claim 1,
The first base layer may be at least one conductive layer selected from the group consisting of a glass substrate, a polyester film, a polyamide film, a polyvinyl chloride film, a polystyrene film and a polyolefin film The method according to claim 1,
Wherein the first conductive layer comprises gold, silver, platinum, palladium, copper, aluminum, nickel, chromium, titanium, iron, cobalt, tin, indium oxide, tin oxide, titanium oxide, cadmium oxide or copper iodide. The method according to claim 1,
Wherein the first conductive layer is formed on one surface of the first or second base layer via an anchor layer or a dielectric layer. The method according to claim 1,
Wherein the pressure-sensitive adhesive layer has a storage elastic modulus at a temperature of 50 DEG C and a frequency of 1 rad / sec of 0.1 x 10 &lt; ⁴ &gt; Pa or more. The method according to claim 1,
Wherein the pressure-sensitive adhesive layer has a loss elastic modulus at a temperature of 50 DEG C and a frequency of 1 rad / sec of 1.0 x 10 &lt; ⁴ &gt; Pa or less. The method according to claim 1,
Wherein the pressure-sensitive adhesive layer comprises a pressure-sensitive adhesive polymer in a crosslinked state. 8. The method of claim 7,
Wherein the adhesive polymer has a weight average molecular weight within the range of 300,000 to 1,000,000. 8. The method of claim 7,
Wherein the adhesive polymer comprises a first monomeric polymerization unit having an alkyl group having not less than 5 carbon atoms and a crosslinkable monomeric polymerization unit. 10. The method of claim 9,
Wherein the first monomer is an alkyl (meth) acrylate having a branched chain or straight chain alkyl group having 5 or more carbon atoms. 10. The method of claim 9,
Wherein the first monomer polymerization unit is contained in a proportion of more than 50 parts by weight based on 100 parts by weight of the sticking polymer. 10. The method of claim 9,
Wherein the crosslinkable monomer is contained in an amount of 1 part by weight to 30 parts by weight relative to 100 parts by weight of the adhesive polymer. 10. The method of claim 9,
Wherein the adhesive polymer further comprises a second monomer polymerization unit having an alkyl group having 1 to 4 carbon atoms. 14. The method of claim 13,
And the second monomer is alkyl (meth) acrylate having a branched or straight-chain alkyl group having 1 to 4 carbon atoms. 14. The method of claim 13,
And the second monomer is contained in an amount of 1 part by weight to 30 parts by weight based on 100 parts by weight of the adhesive polymer. 8. The method of claim 7,
Wherein the pressure-sensitive adhesive layer further comprises 0.01 to 10 parts by weight of a crosslinking agent relative to 100 parts by weight of the adhesive polymer. The method according to claim 1,
And a second conductive layer formed on one surface of the second base layer and the second base layer and having a surface step difference, wherein the surface of the first base layer, on which the first conductive layer is not formed, Wherein the surface having the step of the adhesive layer is present in an attached state by the adhesive layer. 18. The method of claim 17,
And the surface step difference of the second conductive layer is derived from the pattern electrode formed on the surface of the second conductive layer. 19. The method of claim 18,
Wherein the pattern electrode comprises any one of silver (Ag), aluminum (Al), copper (Cu), chromium (Cr), nickel (Ni), and molybdenum (Mo) or an alloy thereof. 18. The method of claim 17,
Wherein the thickness of the adhesive layer is not less than 2 占 퐉 thick relative to the thickness of the surface step difference. A touch panel comprising the conductive laminate of claim 1.

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