JP2018164985A - Light-transmissive conductive film with protective film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light-transmissive conductive film with a protective film which is less likely to cause a curl.SOLUTION: A light-transmissive conductive film 1 with a protective film 4 of this invention comprises the light-transmissive conductive film 1 and the protective film 4, the light-transmissive film 1 comprises a conductive layer 3 having light transmitting performance and conductivity, and having a substrate 2, in which the protective film 4 is arranged on an opposite side to the conductive layer 3 of the substrate 2, and when the XRD measurement is carried out from the opposite side to the conductive layer 3 of the protective film 4, a value in the following formula (1) is 0.3-0.8. (Imax-Imin)/Iave...formula (1), wherein, Imax: the strongest intensity value where the sample is rotated 360° in the planar direction with respect to the main peak; Imin: the weakest intensity value where the sample is rotated 360° in the planar direction with respect to the main peak; Iave: an average intensity value where the sample is rotated 360° in the planar direction with respect to the main peak.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a light-transmitting conductive film with a protective film in which a protective film is disposed on the surface of a light-transmitting conductive film having light transmittance and conductivity.

  In recent years, touch panel liquid crystal display devices have been widely used in electronic devices such as smartphones, mobile phones, notebook computers, tablet PCs, copiers, and car navigation systems. In a wide range of fields such as liquid crystal display devices and light control glass electrodes, a light transmissive conductive film in which a transparent conductive layer is laminated on a substrate is used. A protective film may be provided on the surface opposite to the transparent conductive layer of the base film of the light transmissive conductive film. By providing the protective film, the surface of the base film opposite to the transparent conductive layer is prevented from being contaminated or damaged.

  In a product manufacturing process such as a touch panel, the light transmissive conductive film is heat-treated in a plurality of steps. An example of a manufacturing process of a touch panel will be described. Usually, heat treatment is performed in a plurality of steps in order to produce an electrode and to produce a wiring. For example, when producing an electrode, the light-transmitting conductive film is heat-treated to crystallize the transparent conductive layer by heating for 10 to 90 minutes in the temperature range of 90 to 170 ° C. with the surface protective film attached. A process is performed. After this step, an electrode is manufactured through steps such as etching. In such a heat treatment step of the light-transmitting conductive film with a surface protective film, deformation called curl may occur.

  In Patent Document 1, a base film (surface protective film) containing polyethylene terephthalate and / or polyethylene naphthalate having a thermal shrinkage rate of 0.9% or less in both the MD direction (flow direction) and the TD direction (width direction). ) Is disclosed.

  Patent Document 2 discloses a light-transmitting conductive film in which the thickness of a film substrate and the thickness and properties of a hard coat are controlled.

JP 2004-59860 A JP 2011-31457 A

  As described above, when heat treatment is performed in a product manufacturing process such as a touch panel and curling occurs, the handling property is lowered during inspection and in subsequent processes. For this reason, a light-transmitting conductive film with a surface protective film with controlled curl is desirable. However, curling often occurs even when the surface protective film and / or hard coat film of the above method is used.

  An object of the present invention is to provide a light-transmitting conductive film with a protective film that hardly causes curling.

  According to a wide aspect of the present invention, the light-transmissive conductive film includes a light-transmissive conductive film and a protective film disposed on one surface side of the light-transmissive conductive film. Comprising a conductive layer having conductivity and a substrate disposed on one surface side of the conductive layer, the protective film being disposed on the side opposite to the conductive layer side of the substrate; When the XRD measurement of the said protective film is performed from the opposite side to the said conductive layer of the said protective film, the value of following formula (1) is 0.3-0.8, The light transmittance with a protective film A conductive film is provided.

(Imax−Imin) / Iave (1)
Imax: strongest intensity when rotated 360 ° in the plane direction with respect to the main peak Imin: weakest intensity when rotated 360 ° in the plane direction with respect to the main peak Iave: with respect to the main peak Average value of strength when rotated 360 ° in the plane direction

  In a specific aspect of the light-transmitting conductive film with a protective film according to the present invention, when XRD measurement of the protective film is performed from the opposite side of the protective film to the conductive layer, the main peak 2θ is 25. It is in the range of not less than 27 ° and not more than 27 °, or in the range of not less than 13.5 ° and not more than 14.5 °.

  On the specific situation with the transparent conductive film with a protective film which concerns on this invention, the material of the said protective film contains a polypropylene.

  The light-transmitting conductive film with a protective film according to the present invention includes a light-transmitting conductive film and a protective film disposed on one surface side of the light-transmitting conductive film, and the light-transmitting conductive film is A conductive layer having optical transparency and conductivity, and a base material disposed on one surface side of the conductive layer, and the protective film is provided on the opposite side of the base material from the conductive layer side. When the XRD measurement of the protective film is performed from the side opposite to the conductive layer of the protective film, the value of the formula (1) is 0.3 or more and 0.8 or less, Curling can be made difficult to occur in the light-transmitting conductive film with film.

FIG. 1 is a cross-sectional view showing a light-transmitting conductive film with a protective film according to the first embodiment of the present invention. FIG. 2 is a cross-sectional view showing a light-transmitting conductive film with a protective film according to the second embodiment of the present invention. FIG. 3: is sectional drawing which shows a state when the conductive layer of the transparent conductive film with a protective film which concerns on the 1st Embodiment of this invention is made into the pattern-shaped conductive layer.

  Details of the present invention will be described below.

  The light-transmitting conductive film with a protective film according to the present invention includes a light-transmitting conductive film and a protective film.

  The said protective film is provided with the protective film base material and the adhesion layer, and is arrange | positioned at the one surface side of the said transparent conductive film.

  The light transmissive conductive film includes a conductive layer and a base material. The conductive layer has light transmittance and conductivity. The base material is disposed on one surface side of the conductive layer.

  In the light-transmitting conductive film with a protective film according to the present invention, the protective film is disposed on the side of the substrate opposite to the conductive layer side.

  In the transparent conductive film with a protective film according to the present invention, when the XRD measurement of the protective film is performed from the opposite side of the protective film to the conductive layer, the value of the following formula (1) is 0.3 or more. 0.8 or less.

(Imax−Imin) / Iave (1)
Imax: strongest intensity when rotated 360 ° in the plane direction with respect to the main peak Imin: weakest intensity when rotated 360 ° in the plane direction with respect to the main peak Iave: with respect to the main peak Average value of strength when rotated 360 ° in the plane direction

  In this invention, since said structure is provided, it can make it hard to produce a curl in the transparent conductive film with a protective film. For this reason, handling property becomes high at the time of inspection and use.

  From the viewpoint of making it more difficult to curl, the value of the above formula (1) is preferably 0.34 or more, preferably 0.70 or less, and more preferably 0.58 or less.

  From the viewpoint of making the curl more difficult to occur, when the XRD measurement of the protective film is performed from the side opposite to the conductive layer of the protective film, the main peak 2θ is within the range of 25 ° to 27 °. Preferably, it is within a range of 13.5 ° to 14.5 °. 2θ of the main peak may be in the range of 25 ° to 27 °, or may be in the range of 13.5 ° to 14.5 °.

  Specifically, the XRD measurement can be performed as follows. In addition, XRD measurement may be performed before a protective film is laminated | stacked on another member in a transparent conductive film.

  X-ray diffraction is measured by a thin film method using a Rigaku Corporation thin film evaluation data horizontal X-ray diffractometer SmartLab or equivalent. Specifically, a parallel beam optical arrangement is used, and a CuKα ray (wavelength: 1.5418Å) is used as a light source at a power of 40 kV and 30 mA. A solar slit of 5.0 °, a height control slit of 10 mm, and an incident slit of 0.1 mm was used for the incident side slit, and a parallel slit analyzer (PSA) 0.114 deg. Is used. A scintillation counter is used for the detector. The edge of the protective film may be fixed to an ordinary smooth sample stage with an adhesive tape or the like, and the protective film is adsorbed and fixed to the extent that the protective film is not uneven using a porous adsorption sample holder. Also good. In addition, the said protective film is arrange | positioned so that it can measure from the opposite side to the said conductive layer of the said protective film. At this time, when the protective film has an MD direction and a TD direction, the protective film aligns the MD direction of the protective film in a direction oblique to the protective film along the path from the incidence of X-rays to detection. .

  The step interval and the measurement speed are appropriately adjusted so that the X-ray diffraction pattern can be recognized. As an example, when measuring the main peak of the protective film, it is preferable to set the X-ray incident angle to 0.35 °, and measure at a step interval of 0.01 ° and a measurement speed of 3.0 ° / min. . The measurement range of 2θ is 10 ° to 90 °. The obtained X-ray diffraction pattern does not need to be monochromatic, and a value obtained by subtracting the background may be used as the peak intensity.

  In order to measure the crystallinity distribution in the plane direction with respect to the main peak, the same optical system as described above is used to measure the φ axis in the range of −180 ° to + 180 °. As an example, the step interval of φ axis and the measurement speed are preferably 0.2 ° step interval and 15 ° / min measurement speed. The incident angle of X-ray is set to 0.35 °, and 2θ is measured according to the main peak of the protective film. The obtained X-ray diffraction pattern does not need to be monochromatic, and a value obtained by subtracting the background may be used as the peak intensity.

  The substrate preferably includes a substrate film, preferably includes a hard coat layer, and preferably includes an undercoat layer.

  Moreover, it is preferable that the light-transmitting conductive film with a protective film according to the present invention is annealed. By the annealing treatment, the crystallinity of the conductive layer can be increased.

  When the light-transmitting conductive film with a protective film according to the present invention is used in a liquid crystal display device, curling can be made difficult to occur, so that the alignment accuracy is increased and display quality can be improved. Therefore, the light transmissive conductive film can be suitably used for a liquid crystal display device, and can be suitably used for a touch panel.

  Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a cross-sectional view showing a light-transmitting conductive film with a protective film according to the first embodiment of the present invention.

  A light-transmissive conductive film 1 with a protective film shown in FIG. 1 includes a base material 2, a conductive layer 3, and a protective film 4. The light transmissive conductive film includes a base material 2 and a conductive layer 3.

  The substrate 2 has a first surface 2a and a second surface 2b. The first surface 2a and the second surface 2b are opposed to each other. A conductive layer 3 is laminated on the first surface 2 a of the substrate 2. The first surface 2a is a surface on the side where the conductive layer 3 is laminated. The substrate 2 is a member disposed between the conductive layer 3 and the protective film 4 and is a support member for the conductive layer 3.

  A protective film 4 is laminated on the second surface 2 b of the substrate 2. The second surface 2b is a surface on the side where the protective film 4 is laminated. By providing the protective film 4, the second surface 2 b of the substrate 2 can be protected. In this embodiment, the value of Formula (1) of the protective film 4 is 0.3 or more and 0.8 or less.

  The substrate 2 includes a substrate film 11, first and second hard coat layers 12 and 13, and an undercoat layer 14. The base film 11 is made of a material having high light transmittance. On the surface of the base film 11 on the conductive layer 3 side, a second hard coat layer 13 and an undercoat layer 14 are laminated in this order. The undercoat layer 14 is in contact with the conductive layer 3.

  A first hard coat layer 12 is laminated on the surface of the base film 11 on the protective film 4 side. The first hard coat layer 12 is in contact with the protective film 4.

  The conductive layer 3 is made of a material having high light transmittance and high conductivity. The conductive layer 3 is laminated on the first surface 2 a of the substrate 2.

  The protective film may be laminated on the second surface of the base material by an adhesive layer. It is preferable that the 2nd surface of a base material is in contact with the said adhesive layer of a protective film.

  FIG. 2 is a cross-sectional view showing a light-transmitting conductive film with a protective film according to the second embodiment of the present invention.

  In the light transmissive conductive film 1A with the protective film shown in FIG. 2, the first hard coat layer 12 is not provided. The light-transmitting conductive film 1A with a protective film has a base 2A in which an undercoat layer 14, a second hard coat layer 13, and a base film 11 are laminated in this order. In the light transmissive conductive film 1A with the protective film, the protective film 4 is directly laminated on the surface of the base film 11 opposite to the conductive layer 3.

  In the light-transmitting conductive film with a protective film according to the present invention, the first hard coat layer may not be provided like the light-transmitting conductive film with a protective film 1A. A protective film may be directly laminated on the surface of the base film. Further, at least one of the second hard coat layer and the undercoat layer may not be provided. On the surface of the base film on the conductive layer side, the undercoat layer and the conductive layer may be laminated in this order, or the conductive layer may be laminated directly on the base film. The undercoat layer may be a single layer or a multilayer.

  Next, the manufacturing method of the transparent conductive film 1 with a protective film shown in FIG. 1 is demonstrated.

  The light transmissive conductive film 1 can be produced, for example, by the following method.

  A first hard coat layer 12 is formed on one surface of the base film 11. Specifically, when an ultraviolet curable resin is used as the resin, a photocurable monomer and a photoinitiator are stirred in a diluent to prepare a coating solution. The obtained coating liquid is applied onto the base film 11 and the resin is cured by irradiating with ultraviolet rays to form the first hard coat layer 12.

  Subsequently, the protective film 4 is formed on the first hard coat layer 12. When a protective film provided with a pressure-sensitive adhesive layer on a base sheet is used as the protective film 4, the adhesive surface is bonded to the surface of the first hard coat layer 12, and the first hard coat layer 12 is then bonded. The protective film 4 can be formed.

  Next, the second hard coat layer 13 is formed on the surface of the base film 11 opposite to the first hard coat layer 12. Specifically, when an ultraviolet curable resin is used as the resin, a photocurable monomer and a photoinitiator are stirred in a diluent to prepare a coating solution. The obtained coating liquid is applied on the surface of the base film 11 opposite to the first hard coat layer 12 side, and the resin is cured by irradiating ultraviolet rays to form the second hard coat layer 13. .

Next, the undercoat layer 14 is formed on the second hard coat layer 13. Specifically, when SiO ₂ is used, the undercoat layer 14 can be formed on the second hard coat layer 13 by vapor deposition or sputtering.

  As described above, the first and second hard coat layers 12 and 13 and the undercoat layer 14 are formed on the base film 11. In the present invention, the first and second hard coat layers 12 and 13 and the undercoat layer 14 may not be provided. In this case, the surface of the base film 11 on the conductive layer 3 side is the first surface 2 a of the base material 2, and the surface of the base film 11 on the protective film 4 side is the second surface of the base material 2. It is the surface 2b.

  Next, the light-transmitting conductive film 1 with a protective film can be produced by forming the conductive layer 3 on the undercoat layer 14.

  Although the formation method of a conductive layer is not specifically limited, The method by vapor deposition or sputtering etc. can be used. The formed conductive layer can be improved in crystallinity by annealing. The annealing treatment may be performed in a state where a protective film is used on the side opposite to the conductive layer side of the substrate.

  As shown in FIG. 3, the light-transmitting conductive film 1 with a protective film is used as the light-transmitting conductive film 1X with a protective film by forming the conductive layer 3 (FIG. 1) into a patterned conductive layer 3X. it can. A patterned conductive layer 3X can be formed by partially forming a resist layer on the surface of the conductive layer 3 opposite to the base film 11 side and performing an etching process. After the etching process, washing with water is performed.

  The annealing temperature is preferably 120 ° C. or higher, more preferably 140 ° C. or higher, preferably 170 ° C. or lower, and more preferably 160 ° C. or lower.

  The treatment time for the annealing treatment is preferably 5 minutes or more, more preferably 10 minutes or more, preferably 60 minutes or less, more preferably 30 minutes or less.

  The transparent conductive film 1X with a protective film may be used with the protective film 4 laminated, or may be used after the protective film 4 is peeled off.

  Hereinafter, the detail of each layer which comprises a transparent conductive film with a protective film is demonstrated.

(Base material)
The total thickness of the substrate is preferably 23 μm or more, more preferably 50 μm or more, preferably 300 μm or less, more preferably 200 μm or less.

Base film;
The base film preferably has high light transmittance. Accordingly, the material of the base film is not particularly limited. For example, polyolefin, polyethersulfone, polysulfone, polycarbonate, cycloolefin polymer, polyarylate, polyamide, polymethyl methacrylate, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate. Examples include phthalate, triacetylcellulose, and cellulose nanofiber. The material for the base film may be used alone or in combination.

  The thickness of the base film is preferably 5 μm or more, more preferably 20 μm or more, preferably 190 μm or less, more preferably 125 μm or less. When the thickness of the base film is not less than the above lower limit and not more than the above upper limit, the pattern of the conductive layer can be made even less visible.

  Regarding the light transmittance of the substrate film, the average transmittance in the visible light region having a wavelength of 380 to 780 nm is preferably 85% or more, and more preferably 90% or more.

  Moreover, the base film may contain various stabilizers, ultraviolet absorbers, plasticizers, lubricants, or colorants.

First and second hard coat layers;
Each of the first and second hard coat layers is preferably composed of a binder resin. The binder resin is preferably a cured resin. As the curable resin, thermosetting resin, active energy ray curable resin, or the like can be used. From the viewpoint of improving productivity and economy, the curable resin is preferably an ultraviolet curable resin.

  Examples of the photocurable monomer for forming the ultraviolet curable resin include 1,6-hexanediol diacrylate, 1,4-butanediol diacrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, and tetraethylene glycol diacrylate. , Tripropylene glycol diacrylate, neopentyl glycol diacrylate, 1,4-butanediol dimethacrylate, poly (butanediol) diacrylate, tetraethylene glycol dimethacrylate, 1,3-butylene glycol diacrylate, triethylene glycol diacrylate Such as triisopropylene glycol diacrylate, polyethylene glycol diacrylate and bisphenol A dimethacrylate Triacrylate compounds such as trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, pentaerythritol monohydroxytriacrylate and trimethylolpropane triethoxytriacrylate; of pentaerythritol tetraacrylate and di-trimethylolpropane tetraacrylate And tetraacrylate compounds such as dipentaerythritol (monohydroxy) pentaacrylate. As the ultraviolet curable resin, a polyfunctional acrylate compound having five or more functions may be used. The said polyfunctional acrylate compound may be used independently and may use multiple together. Moreover, you may add a photoinitiator, a photosensitizer, a leveling agent, a diluent, etc. to the said polyfunctional acrylate compound.

  Moreover, the 1st hard-coat layer may be comprised with the resin part and the filler. When the first hard coat layer contains a filler, the pattern of the conductive layer can be made even less visible. Note that when the first hard coat layer contains a filler, it may be distorted, and display light may be difficult to see when used in a liquid crystal display device. Therefore, it is desirable that the first hard coat layer does not contain a filler and is constituted only by the resin portion from the viewpoint of making it difficult to produce the yuzu skin. Or it is preferable that the average particle diameter of a filler is smaller than the thickness of a 1st hard-coat layer, and the filler does not protrude in the surface of a 1st hard-coat layer.

  Examples of the filler include, but are not limited to, metal oxides such as silica, iron oxide, aluminum oxide, zinc oxide, titanium oxide, silicon dioxide, antimony oxide, zirconium oxide, tin oxide, cerium oxide, and indium-tin oxide. Product particles; resin particles such as silicone, (meth) acryl, styrene, melamine, and the like. More specifically, resin particles such as crosslinked poly (meth) methyl acrylate can be used. The said filler may be used independently and may use multiple together.

  The first and second hard coat layers may each contain various stabilizers, ultraviolet absorbers, plasticizers, lubricants, or colorants.

Undercoat layer;
The undercoat layer is, for example, a refractive index adjustment layer. By providing the undercoat layer, the difference in refractive index between the conductive layer and the second hard coat layer or substrate film can be reduced, so that the light transmissive conductive film can be made more transparent. Can be increased.

The material constituting the undercoat layer is not particularly limited as long as it has a refractive index adjusting function, and is an inorganic material such as SiO _x (x = 1.0 to 2.0), SiO ₂ , MgF ₂ , Al ₂ O _3. And organic materials such as acrylic resin, urethane resin, melamine resin, alkyd resin, and siloxane polymer. The undercoat layer may be a single layer or a multilayer.

  The undercoat layer can be formed by a vacuum deposition method, a sputtering method, an ion plating method, or a coating method.

(Conductive layer)
The conductive layer is made of a light-transmitting conductive material. As the conductive material is not particularly limited, for example, IZO (indium zinc oxide) or, In-based oxides such as ITO (indium tin _oxide), Sn, such as SnO 2, FTO (fluorine-doped tin oxide) Oxide, AZO (aluminum zinc oxide), Zn oxide such as GZO (gallium zinc oxide), sodium, sodium-potassium alloy, lithium, magnesium, aluminum, magnesium-silver mixture, magnesium-indium mixture, aluminum - lithium alloy, Al / _Al 2 _{O 3} mixture, Al / LiF mixture, a metal such as gold, CuI, Ag nanowire (AgNW), such as carbon nanotubes (CNT) or conductive transparent polymers. The said electroconductive material may be used independently and may use multiple together.

From the viewpoint of further increasing the conductivity and further increasing the light transmittance, the conductive material is selected from In-based oxides such as IZO (indium zinc oxide) and ITO (indium tin oxide), SnO ₂ , FTO. Sn-based oxides such as (fluorine-doped tin oxide), Zn-based oxides such as AZO (aluminum zinc oxide) and GZO (gallium zinc oxide) are preferable, and ITO (indium tin oxide) is preferable. Is more preferable.

  The thickness of the conductive layer is preferably 12 nm or more, more preferably 16 nm or more, still more preferably 17 nm or more, preferably 100 nm or less, more preferably 50 nm or less, and even more preferably 19.9 nm or less.

  When the thickness of the conductive layer is not less than the above lower limit, the resistance value of the light transmissive conductive film can be effectively reduced, and the conductivity can be further increased. When the thickness of the conductive layer is less than or equal to the above upper limit, the pattern of the conductive layer can be made less visible and the light transmissive conductive film can be made even thinner.

(Protective film)
The protective film is preferably composed of a protective film substrate and an adhesive layer. The protective film includes a protective film substrate and an adhesive layer, and the adhesive layer of the protective film is disposed on the conductive layer side, and the protective film is formed from the side opposite to the adhesive layer of the protective film substrate. It is preferable to perform XRD measurement of the protective film from the side opposite to the conductive layer. The protective film preferably has a protective film substrate.

  The base sheet preferably has high light transmittance. The material of the base sheet is not particularly limited, but for example, polyolefin, polyethersulfone, polysulfone, polycarbonate, cycloolefin polymer, polyarylate, polyamide, polymethyl methacrylate, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate , Triacetyl cellulose, and cellulose nanofibers.

  Examples of the polyolefin include polyethylene and polypropylene.

  Since it is easy to control the value of the formula (1) within a suitable range, the material of the protective film preferably includes polyolefin, preferably includes polypropylene, and the material of the protective film substrate is Polyolefin is preferable, and polypropylene is preferable.

  The polypropylene is obtained by polymerizing a propylene monomer. Polypropylene is a polymer. The polymer includes a copolymer. Examples of polypropylene include a homopolymer of propylene monomer and a copolymer of polymerization components mainly composed of propylene monomer. In the copolymer of the polymerization component mainly composed of the propylene monomer, the content of the propylene monomer is 50% by weight or more, preferably 80% by weight or more, more preferably 90% by weight in 100% by weight of the polymerizable polymerization component. % By weight or more. The form of copolymerization may be random or block.

  Examples of polypropylene include propylene homopolymer, propylene random polymer, and propylene block polymer. Polypropylene is preferably a homopolymer of propylene monomer, and is preferably a propylene homopolymer.

  The pressure-sensitive adhesive layer can be composed of a (meth) acrylic pressure-sensitive adhesive, a rubber-based pressure-sensitive adhesive, a urethane-based adhesive, or an epoxy-based adhesive. From the viewpoint of suppressing an increase in adhesive force due to heat treatment, the adhesive layer is preferably composed of a (meth) acrylic adhesive.

  The (meth) acrylic pressure-sensitive adhesive is a pressure-sensitive adhesive in which a crosslinking agent, a tackifier resin, various stabilizers, and the like are added to a (meth) acrylic polymer as necessary.

  The (meth) acrylic polymer is not particularly limited, but (meth) acrylic copolymer obtained by copolymerizing a mixed monomer containing a (meth) acrylic acid ester monomer and another copolymerizable monomer. A polymer is preferred.

  Although it does not specifically limit as said (meth) acrylic acid ester monomer, It is obtained by esterification reaction of the primary or secondary alkyl alcohol whose carbon number of an alkyl group is 1-12, and (meth) acrylic acid ( A (meth) acrylate monomer is preferable, and specific examples include ethyl (meth) acrylate, butyl (meth) acrylate, and (meth) acrylate-2-ethylhexyl. The said (meth) acrylic acid ester monomer may be used independently and may use multiple together.

  Examples of other polymerizable monomers that can be copolymerized include hydroxyalkyl (meth) acrylates such as 2-hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, and hydroxybutyl (meth) acrylate; Isobornyl (meth) acrylate, hydroxyalkyl (meth) acrylate, glycerin dimethacrylate, glycidyl (meth) acrylate, 2-methacryloyloxyethyl isocyanate, (meth) acrylic acid, itaconic acid, maleic anhydride, crotonic acid, malein Examples thereof include functional monomers such as acid and fumaric acid. The said other polymerizable monomer which can be copolymerized may be used independently, and may use multiple together.

  The crosslinking agent is not particularly limited, and for example, an isocyanate crosslinking agent, an epoxy crosslinking agent, a melamine crosslinking agent, a peroxide crosslinking agent, a urea crosslinking agent, a metal alkoxide crosslinking agent, a metal chelate crosslinking agent. Agents, metal salt crosslinking agents, carbodiimide crosslinking agents, oxazoline crosslinking agents, aziridine crosslinking agents, amine crosslinking agents, polyfunctional acrylates and the like. The above crosslinking agents may be used alone or in combination.

  The tackifying resin is not particularly limited, and examples thereof include petroleum resins such as aliphatic copolymers, aromatic copolymers, aliphatic / aromatic copolymers, and alicyclic copolymers. Coumarone-indene resin; terpene resin; terpene phenol resin; rosin resin such as polymerized rosin; phenol resin; xylene resin. The tackifying resin may be a hydrogenated resin. The tackifying resins may be used alone or in combination.

  The thickness of the pressure-sensitive adhesive layer is preferably 1 μm or more, more preferably 5 μm or more, preferably 40 μm or less, more preferably 25 μm or less. When the thickness of the pressure-sensitive adhesive layer is not less than the above lower limit and not more than the above upper limit, the protective film is not peeled off in the process of manufacturing the touch panel, and when the protective film is peeled off, the light-transmissive conductive film has a pressure-sensitive adhesive. The adhesion residue of the layer can be suppressed.

  The thickness of the protective film is preferably 25 μm or more, more preferably 50 μm or more, preferably 300 μm or less, more preferably 200 μm or less. When the thickness of the protective film is not less than the above lower limit and not more than the above upper limit, the curl can be further reduced.

  Hereinafter, the present invention will be described in more detail based on specific examples and comparative examples. The present invention is not limited to the following examples.

(ITO film-A)
An acrylic hard coat resin in which zirconia particles having an average particle diameter of 20 nm were dispersed was applied to one surface of a 125 μm thick PET film to obtain a second hard coat layer having a thickness of 0.8 μm. An acrylic hard coat resin was applied to the other surface of the PET film to obtain a first hard coat layer having a thickness of 0.5 μm. In this way, a double-sided hard coat film was obtained.

This hard coat film was placed in a vacuum apparatus and evacuated to 4.5 × 10 ⁻⁴ Pa or less. Thereafter, argon gas (concentration: 99.9%, the same applies hereinafter) was introduced, and the SiO _x layer was formed to a thickness of 0.5 nm from the second hard coat layer side in an argon gas atmosphere by a DC magnetron sputtering method. Then, the oxygen gas was adjusted so that the set value of the degree of oxidation was 10% by a sputtering process monitor (Speedflo, manufactured by GENCOA), and the SiO _x layer had a thickness of 20.0 nm. The film was formed as follows. Further, only an argon gas was introduced to form a SiO _x layer having a thickness of 0.5 nm. Next, indium tin oxide (ITO) was continuously laminated on the SiO _x layer. Specifically, an ITO sintered body target of 7% by weight of SnO ₂ is used as a cathode having a maximum horizontal speed density of 1000 gauss on the target surface, and an ITO layer having a thickness of 18 nm is formed of argon having an oxygen partial pressure of 0.004 Pa. ITO film-A was obtained by performing sputter deposition in a gas atmosphere.

(ITO film-B)
Acrylic hard coat resin was applied to both sides of a 125 μm thick PET film, and a hard coat layer having a thickness of 0.3 μm was provided on both sides to obtain a double-sided hard coat film.

This hard coat film was placed in a vacuum apparatus and evacuated to 4.5 × 10 ⁻⁴ Pa or less. Thereafter, argon gas (concentration: 99.9%, the same applies hereinafter) was introduced, and a SiO _x layer was formed to a thickness of 0.5 nm in an argon gas atmosphere by a DC magnetron sputtering method. Then, the oxygen gas was adjusted so that the set value of the degree of oxidation was 10% by a sputtering process monitor (Speedflo, manufactured by GENCOA), and the SiO _x layer was formed to a thickness of 30.0 nm. Further, only an argon gas was introduced to form a SiO _x layer having a thickness of 0.5 nm. Next, indium tin oxide (ITO) was continuously laminated on the SiO _x layer. Specifically, an ITO sintered body target of 7% by weight of SnO ₂ was used as a cathode having a maximum horizontal speed density of 1000 gauss on the target surface, and an ITO layer having a thickness of 40 nm was formed of argon with an oxygen partial pressure of 0.004 Pa. An ITO film-B was obtained by performing sputter deposition in a gas atmosphere.

(PET protective film)
The PET resin pellets were melted, and the PET resin was discharged into a film by the T-die method. Thereafter, using a biaxial stretching apparatus, the stretching ratio and the conveyance speed were adjusted so as to obtain a predetermined in-plane orientation strength, and two types of 50 μm thick PET film substrates were obtained. Thereafter, an acrylic adhesive was applied to one side of each PET film so as to have a thickness of 10 μm, dried, and aged for 5 days, whereby PET protective films (PET-A, PET-B) were obtained. Obtained.

(PP protective film)
The PP raw material was extruded from a T die, quenched and solidified with a cooling roll, and then trimmed with a trimming roll to obtain a PP film base material-A base material. At this time, the cooling temperature and the conveyance speed were adjusted so as to obtain a predetermined in-plane orientation strength. Thereafter, an acrylic pressure-sensitive adhesive was applied to one side of the PP film substrate-A so as to have a thickness of 10 μm, dried, and aged for 5 days to obtain a PP protective film (PP-A). .

  The PP raw material was extruded from a T die, rapidly cooled with a cooling roll, solidified, and then longitudinally adjusted so as to obtain a predetermined in-plane orientation strength by a sequential biaxial stretching method. The transverse stretching was quadruple stretching. About other, it carried out similarly to PP-A, and obtained the protective film (PP-B, PP-C, PP-D) made from PP.

(Examples 1 to 5 and Comparative Examples 1 and 2)
A light transmissive conductive film with a protective film in which an ITO film (light transmissive conductive film) of the type shown in Table 1 below and a protective film were laminated was prepared.

(Evaluation)
(1) XRD measurement: In-plane orientation strength X-ray diffraction was measured by a thin film method using a horizontal X-ray diffraction apparatus SmartLab for thin film evaluation manufactured by Rigaku Corporation. Specifically, a parallel beam optical arrangement was used, and a CuKα ray (wavelength: 1.5418Å) was used as a light source at a power of 40 kV and 30 mA. A solar slit of 5.0 °, a height control slit of 10 mm, and an incident slit of 0.1 mm was used for the incident side slit, and a parallel slit analyzer (PSA) 0.114 deg. Was used. A scintillation counter was used as a detector. The sample was adsorbed and fixed using a porous adsorption sample holder to such an extent that the sample did not have irregularities. In addition, the sample was arrange | positioned so that it could measure from the opposite side to the adhesive layer of a protective film. At this time, the sample was aligned in the MD direction in a direction oblique to the protective film sample along the path from the incidence of X-rays to detection.

  The X-ray incident angle was set to 0.35 °, and the measurement was performed at a step interval of 0.01 ° and a measurement speed of 3.0 ° / min. The measurement range of 2θ was 10 ° to 90 °. In order to measure the crystallinity distribution in the plane direction with respect to the main peak of the diffraction line obtained in this way, the same optical system as described above is used, and the φ axis is in the range of −180 ° to + 180 °. Went. Specifically, with respect to the step interval and measurement speed of the φ axis, the step interval was 0.2 ° and the measurement speed was 15 ° / min. The X-ray incident angle was set to 0.35 °, and 2θ was measured in accordance with the main peak of the protective film substrate.

  Table 1 shows the result of (Imax−Imin) / Iave.

(2) Evaluation of curl A protective film is pasted on the opposite side of the ITO film from the conductive layer, cut to 500 mm x 500 mm, heated in an air dryer at 140 ° C for 1 hour, and then allowed to cool at room temperature for 2 hours. did. The four corners were measured with a digital caliper. In addition, the heat treatment and the cooling treatment were arranged so that the protective film side was on the bottom. Moreover, the measurement measured both the case where the protective film side was down and the case where the ITO film side was down. The float on the ITO film side was defined as +, and the float on the protective film side was defined as-. Curl was determined according to the following criteria.

[Curl criteria]
◎: Floating at 4 corners −10 mm or more and +10 mm or less ○: Floating at 4 corners −15 mm or more and less than −10 mm or more than +10 mm and +15 mm or less ×: Floating at 4 corners is less than −15 mm or +15 mm Over

  Details and results are shown in Table 1 below.

  In all the examples, when XRD measurement of the protective film is performed, 2θ is in the range of 25 ° or more and 27 ° or less, or 2θ is 13.5 ° or more and 14.5 ° or less. It was in the range.

DESCRIPTION OF SYMBOLS 1,1A, 1X ... Light-transmitting conductive film with protective film 2, 2A ... Base material 2a ... First surface 2b ... Second surface 3 ... Conductive layer 3X ... Patterned conductive layer 4 ... Protective film 11 ... Base Material film 12 ... First hard coat layer 13 ... Second hard coat layer 14 ... Undercoat layer

Claims (3)

A light transmissive conductive film, and a protective film disposed on one surface side of the light transmissive conductive film,
The light transmissive conductive film comprises a conductive layer having light transparency and conductivity, and a substrate disposed on one surface side of the conductive layer,
The protective film is arranged on the side opposite to the conductive layer side of the base material,
When the XRD measurement of the said protective film is performed from the opposite side to the said conductive layer of the said protective film, the value of following formula (1) is 0.3-0.8, The light transmittance with a protective film Conductive film.
(Imax−Imin) / Iave (1)
Imax: strongest intensity when rotated 360 ° with respect to main peak Imin: weakest intensity when rotated 360 ° with respect to main peak Iave: intensity when rotated 360 ° with respect to main peak Average value   When XRD measurement of the protective film is performed from the side opposite to the conductive layer of the protective film, 2θ of the main peak is in the range of 25 ° or more and 27 ° or less, or 13.5 ° or more The light-transmitting conductive film with a protective film according to claim 1, which is within a range of 14.5 ° or less.   The light-transmitting conductive film with a protective film according to claim 1 or 2, wherein a material of the protective film includes polypropylene.

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