WO2016006024A1

WO2016006024A1 - Photosensitive conductive film, conductive film set and method of manufacturing surface protection film and base film having conductive pattern using same, and method of manufacturing base film having conductive pattern

Info

Publication number: WO2016006024A1
Application number: PCT/JP2014/068049
Authority: WO
Inventors: 奏美中村; 山崎　宏; 田仲　裕之
Original assignee: 日立化成株式会社
Priority date: 2014-07-07
Filing date: 2014-07-07
Publication date: 2016-01-14

Abstract

This photosensitive conductive film includes, in order: a support film; a conductive layer containing conductive fibers; a photosensitive resin layer; a base film; and a surface protection film. This method of manufacturing a surface protection film/base film having a conductive pattern includes: a first exposure step for applying activation light in a patterned manner to the photosensitive conductive film from the support film side; a second exposure step for applying, after the separation of the support film and in the presence of oxygen, activation light to at least part or all of the portions of the photosensitive conductive film which were not exposed in the first exposure step; and a development step for forming a conductive pattern by developing the conductive layer and the photosensitive resin layer after the second exposure step.

Description

Photosensitive conductive film, conductive film set, surface protection film using the same, and method for producing substrate film with conductive pattern, method for producing substrate film with conductive pattern

The present invention relates to a photosensitive conductive film, a conductive film set, and a method for producing a surface protective film and a substrate film with a conductive pattern using the same, a surface protective film having a two-layer stack-up structure, and a method for producing a substrate film with a conductive pattern The present invention relates to a method for producing a base film with a conductive pattern having a two-layer stack-up structure. In particular, it is related with the base film with a transparent conductive pattern used for flat panel displays, such as a liquid crystal display element, a touch screen, a solar cell.

Liquid crystal display elements and touch screens are used in large electronic devices such as personal computers and televisions, small electronic devices such as car navigation systems, mobile phones and electronic dictionaries, and display devices such as OA and FA devices. In these devices such as liquid crystal display elements, touch screens, solar cells and lighting, a transparent conductive film is used as part of transparent wiring, pixel electrodes or terminals.

Various types of touch panels have already been put to practical use, but in recent years, the use of capacitive touch panels has progressed. The capacitive touch panel is formed with a two-layer structure of a plurality of X electrodes and a plurality of Y electrodes orthogonal to the X electrodes in order to express two-dimensional coordinates by the X axis and the Y axis. .

Conventionally, ITO (Indium-Tin-Oxide), indium oxide, tin oxide, and the like have been used as the material for the transparent conductive film because it exhibits high transmittance to visible light. In an electrode such as a substrate for a liquid crystal display element, a pattern obtained by patterning a transparent conductive film made of the above-described material has become mainstream.

As a method for patterning a transparent conductive film, a method is generally employed in which after forming a transparent conductive film, a resist pattern is formed by a photolithography method, and a predetermined portion of the conductive film is removed by wet etching to form a conductive pattern. In the case of an ITO film and an indium oxide film, a mixed liquid composed of two liquids of hydrochloric acid and ferric chloride is often used as the etching liquid (see, for example, Patent Document 1).

An ITO film or tin oxide film is generally formed by sputtering, but the film quality of the transparent conductive film is likely to change depending on the sputtering method, sputtering power, gas pressure, substrate temperature, type of atmospheric gas, and the like. Differences in the film quality of the transparent conductive film due to variations in sputtering conditions cause variations in the etching rate when the transparent conductive film is wet-etched, and are liable to reduce product yield due to patterning defects. In addition, since the transparent conductive pattern forming method has undergone a sputtering process, a resist forming process, and an etching process, the process is long and has a large cost.

Recently, in order to solve the above problems, attempts have been made to form a transparent conductive pattern using a material in place of ITO, indium oxide, tin oxide or the like.
For example, the following Patent Document 2 discloses a transfer type photosensitivity provided with a support film, a conductive layer containing conductive fibers provided on the support film, and a photosensitive resin layer provided on the conductive layer. Laminate the conductive film on the substrate so that the photosensitive resin layer is in close contact, and then expose and develop the conductive film. A conductive pattern with sufficient adhesion to the substrate and low surface resistivity is sufficient. It is possible to form at a high resolution.

Moreover, in the following Patent Document 3, when exposing a photosensitive resin layer having a conductive layer on the surface, the first exposure is performed through a support film on which a mask is placed, and the second exposure is performed on the support film. A two-stage exposure method is disclosed, which is performed under the removed oxygen. As a result, it is possible to cure the resin to such an extent that only the conductive layer on the surface is removed in the development process at the first exposure process.

JP 2007-257963 A International Publication No. 2010/021224 International Publication No. 2013/051516 JP 2003-205567 A

However, when a transfer type photosensitive conductive film is transferred to a substrate by the method of Patent Document 3 and a substrate with a conductive pattern is produced by exposure and development, the transfer destination substrate does not have a certain thickness. There is a problem that the base material with the conductive pattern breaks during the heating and transport process, and the back surface of the base film on which the photosensitive resin layer and the conductive layer are laminated is damaged or dirty. There was room for improvement in reducing the thickness of the touch panel.

By the way, as a surface protection film for a transparent conductive film, in Patent Document 4, even when placed in a heating environment in the pattern formation of transparent electrodes and wiring, the surface protection film that can perform subsequent peeling work well. Is disclosed. However, in the film configuration described in Patent Document 4, an adhesive for bonding the first and second conductive pattern base materials is required in a capacitive touch panel in which two layers of XY electrodes are formed. There was still room for improvement in making the pattern substrate thinner.
This invention is made | formed in view of the problem which the said prior art has, and provides the method of thinning a base film with a conductive pattern, protecting a base film with a conductive pattern from a damage | wound and dirt.

The present invention solves the above problems. Specific embodiments are shown below.
<1> A photosensitive conductive film including a support film, a conductive layer containing conductive fibers, a photosensitive resin layer, a base film, and a surface protective film in this order.
<2> The photosensitive conductive film according to <1>, wherein the minimum light transmittance in a wavelength region of 450 to 650 nm is 80% or more.
<3> The photosensitive conductive film according to <1> or <2>, wherein the conductive fiber is a silver fiber.
<4> The photosensitive conductive layer according to any one of <1> to <3>, wherein the photosensitive resin layer contains a binder polymer, a photopolymerizable compound having an ethylenically unsaturated bond, and a photopolymerization initiator. the film.
<5> The photosensitive conductive film according to any one of <1> to <4>, wherein the surface protective film is an acrylic adhesive.
<6> a first exposure step of irradiating the conductive layer and the photosensitive resin layer of the photosensitive conductive film according to any one of <1> to <5> with actinic rays in a pattern form from the support film side; ,
A second exposure step of irradiating a part or all of the unexposed portion in the first exposure step of the conductive layer and the photosensitive resin layer with actinic rays in the presence of oxygen after peeling the support film; The manufacturing method of the surface protection film provided with the image development process which forms a conductive pattern by developing the said conductive layer and the said photosensitive resin layer after a said 2nd exposure process, and a base film with a conductive pattern.
<7> A surface protective film obtained by the production method according to <6> and a base film with a conductive pattern, a support film, a conductive layer containing conductive fibers provided on the support film, and the conductive layer Laminating a transfer type photosensitive conductive film having a photosensitive resin layer provided on the conductive pattern side of the surface protective film and the substrate film with a conductive pattern from the photosensitive resin layer side;
A first exposure step of irradiating the conductive layer and the photosensitive resin layer with actinic rays in a pattern from the support film side; and after peeling the support film, in the presence of oxygen, the conductive layer and the photosensitive resin. A second exposure step of irradiating a part or all of the unexposed portion in at least the first exposure step of the layer with actinic rays, and the conductive layer and the photosensitive resin layer after the second exposure step. The manufacturing method of the surface protection film of a 2 layer stack-up structure provided with the image development process which forms a conductive pattern by developing, and a base film with a conductive pattern.
<8> In the method for producing a surface protective film having a two-layer stack-up structure and a base film with a conductive pattern according to <7>, a surface protective film is further obtained from the obtained surface protective film and the base film with a conductive pattern. The manufacturing method of the base film with a conductive pattern of a two-layer stackup structure provided with the process to remove.
<9> The photosensitive conductive film according to any one of <1> to <5>, which is used in the method for producing a substrate film with a conductive pattern according to <7> or <8>, and a support film A conductive film set comprising a transfer type photosensitive conductive film having a conductive layer containing conductive fibers provided on the support film and a photosensitive resin layer provided on the conductive layer.

According to the present invention, the substrate film with a conductive pattern can be thinned to about 30 to 100 μm while protecting the substrate film with a conductive pattern from scratches and dirt.

It is a schematic cross section which shows one Embodiment of the photosensitive conductive film of this invention. It is a schematic cross section which shows one Embodiment of the transfer type photosensitive conductive film of this invention. Manufacturing method of base film with two layers of conductive pattern using conductive film set of photosensitive conductive film and transfer type photosensitive conductive film (manufacturing of surface protective film of two-layer stack-up structure and base film with conductive pattern) It is a schematic cross section which shows the manufacturing method (i) of the method (h) and the base film with a conductive pattern of a two-layer stackup structure. They are a schematic top view (a) and a schematic sectional view (b) showing an example of a capacitive touch panel sensor.

Hereinafter, embodiments of the present invention will be described in detail. In the present specification, “(meth) acrylate” means “acrylate” or “methacrylate” corresponding thereto. “A or B” only needs to include one of A and B, or may include both.

In addition, in this specification, the term “process” is not limited to an independent process, and even if it cannot be clearly distinguished from other processes, the term “process” is used as long as the intended action of the process is achieved. included. The numerical range indicated by using “to” indicates a range including the numerical values described before and after “to” as the minimum value and the maximum value, respectively.

Furthermore, in the present specification, the content of each component in the composition is the sum of the plurality of substances present in the composition unless there is a specific indication when there are a plurality of substances corresponding to each component in the composition. Means quantity. In addition, the exemplary materials may be used alone or in combination of two or more unless otherwise specified.

FIG. 1 is a schematic cross-sectional view of the photosensitive conductive film of the present invention. The photosensitive conductive film shown in FIG. 1 includes a support film 1, a conductive layer 2 containing conductive fibers, a photosensitive resin layer 3, a base film 4, and a surface protective film 5 in this order. In addition, the boundary of each layer does not need to be separated clearly.

Examples of the support film 1 include a polyethylene terephthalate film, a polyethylene film, a polypropylene film, and a polycarbonate film. Among these, a polyethylene terephthalate film is preferable from the viewpoint of transparency and heat resistance. In addition, the support film may be subjected to surface treatment within a range that can be removed from the photosensitive resin layer later.

The thickness of the support film 1 is preferably 5 to 300 μm, more preferably 10 to 200 μm, still more preferably 15 to 100 μm, and particularly preferably 15 to 50 μm. When the thickness of the support film is 5 μm or more, the mechanical strength is improved, and the step of applying the conductive fiber dispersion to form the conductive layer 2 and the photosensitive resin for forming the photosensitive resin layer 3 are performed. In the step of applying the composition, the step of peeling the support film before developing the exposed photosensitive resin layer 3, and the like, it is possible to prevent the support film from being damaged. On the other hand, when the thickness of the support film 1 is 300 μm or less, the resolution of the pattern can be improved when the photosensitive resin layer is irradiated with actinic rays through the support film 1.

The haze value of the support film 1 is preferably 0.01 to 5.0%, more preferably 0.01 to 3.0%, from the viewpoint of improving sensitivity and resolution. It is more preferably from 2.0% to 2.0%, particularly preferably from 0.01% to 1.1%. The haze value can be measured according to JIS K 7105. For example, it can be measured with a commercially available turbidimeter such as NDH-5000 (trade name, manufactured by Nippon Denshoku Industries Co., Ltd.).

Examples of the conductive fibers contained in the conductive layer 2 include metal fibers such as gold, silver, copper, and platinum, and carbon fibers such as carbon nanotubes. From the viewpoint of conductivity, it is preferable to use gold fibers, silver fibers, or copper fibers, and it is more preferable to use silver fibers or copper fibers. Furthermore, silver fiber is preferable from the viewpoint of easily adjusting the conductivity of the formed conductive film.

The metal fiber can be prepared by, for example, a method of reducing metal ions with a reducing agent such as NaBH ₄ or a polyol method. As the carbon nanotubes, commercially available products such as HiPco single-walled carbon nanotubes from Unidym Corporation can be used.

The fiber diameter of the conductive fiber is preferably 1 to 50 nm, more preferably 2 to 20 nm, and further preferably 3 to 10 nm. The fiber length of the metal fiber is preferably 1 to 100 μm, more preferably 2 to 50 μm, still more preferably 3 to 40 μm, and particularly preferably 5 to 35 μm. The fiber diameter and fiber length can be measured with a scanning electron microscope.

The thickness of the conductive layer 2 varies depending on the conductive film to be formed, the use of the conductive pattern and the required conductivity, but is preferably 1 μm or less, more preferably 1 nm to 0.5 μm, and more preferably 5 nm to 0 nm. More preferably, it is 1 μm. When the thickness of the conductive layer 2 is 1 μm or less, the light transmittance in the wavelength range of 450 to 650 nm is high, the pattern formability is excellent, and it is suitable for the production of a transparent electrode.

The conductive layer 2 can have a network structure in which conductive fibers are in contact with each other. The conductive layer 2 having such a network structure may be formed on the surface of the photosensitive resin layer 3 on the support film side, but conductivity is obtained in the surface direction on the surface exposed when the support film is peeled off. If it is, it may be formed in the form included in the support film side surface layer of the photosensitive resin layer 3. The thickness of the conductive layer 2 having a network structure refers to a value measured by a scanning electron microscope.

For example, the conductive layer 2 containing conductive fibers is coated on the support film 1 with a conductive fiber dispersion obtained by adding the above-described conductive fibers to water or a dispersion stabilizer such as an organic solvent or a surfactant. After processing, it can be formed by drying. After drying, the conductive layer 2 formed on the support film 1 may be laminated as necessary.

Coating can be performed by a known method such as a roll coating method, a comma coating method, a gravure coating method, an air knife coating method, a die coating method, a bar coating method, or a spray coating method, but the film thickness distribution is good. In view of the fact that there is little foreign matter mixed into the coating liquid in a closed system, the die coating method is preferred.

In the drying step, it is preferable that the drying temperature is 65 ° C. or less from the viewpoint of preventing convection from forming and forming a Benard cell and becoming difficult to form a low-resistance conductive layer. Moreover, it is preferable that it is 20 degreeC or more from a viewpoint which prevents a solvent volatilizing and it takes time and becomes a problem on a process. The drying temperature is more preferably 25 ° C. or more and less than 65 ° C., more preferably 35 ° C. or more and less than 65 ° C., and particularly preferably 40 to 60 ° C. Drying can be performed with a hot air convection dryer or the like. In the conductive layer 2, the conductive fibers may coexist with a surfactant or a dispersion stabilizer.

The photosensitive resin layer 3 may be formed from a photosensitive resin composition containing (a) a binder polymer, (b) a photopolymerizable compound having an ethylenically unsaturated bond, and (c) a photopolymerization initiator. preferable. Conventionally known ones can be used without particular limitation, but the photosensitive resin composition described in International Publication No. 2013/084886 is preferable.

Specifically, the binder polymer of component (a) preferably has a carboxyl group. The acid value of component (a) is preferably 75 to 200 mgKOH / g, more preferably 75 to 150 mgKOH / g, and 75 to 130 mgKOH / g from the viewpoint of excellent patternability. Further preferred.

The photopolymerizable compound having an ethylenically unsaturated bond as the component (b) is derived from a (meth) acrylate compound having a skeleton derived from pentaerythritol, a (meth) acrylate compound having a skeleton derived from dipentaerythritol, or derived from trimethylolpropane. It is preferable to include a (meth) acrylate compound having a skeleton of, more preferably a (meth) acrylate compound having a skeleton derived from dipentaerythritol or a (meth) acrylate compound having a skeleton derived from trimethylolpropane, More preferably, erythritol triacrylate, dipentaerythritol hexaacrylate, or trimethylolpropane triacrylate is included. These are commercially available as PET-30, DPHA, and TMPTA (all manufactured by Nippon Kayaku Co., Ltd., trade names).

The (C) component photopolymerization initiator preferably contains an oxime ester compound or a phosphine oxide compound. As oxime ester compounds, IRGACURE OXE 01 (1,2-octanedione, 1-[(4-phenylthio) -phenyl, 2- (o-benzoyloxime)], BASF Corporation, trade name) and the like are commercially available. It is available. As the phosphine oxide compound, Lucirin® TPO (2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, trade name, manufactured by BASF Corporation) is commercially available.

The photosensitive resin layer 3 can be formed by applying and drying a photosensitive resin composition having a solid content of about 10 to 60% by mass on the conductive layer 2 formed on the support film 1. However, in this case, the amount of the remaining organic solvent in the photosensitive resin layer after drying is preferably 2% by mass or less in order to prevent the organic solvent from diffusing in the subsequent step. Examples of the solvent include methanol, ethanol, acetone, methyl ethyl ketone, methyl cellosolve, ethyl cellosolve, toluene, N, N-dimethylformamide, propylene glycol monomethyl ether and the like.

The coating can be performed by a known method such as a roll coating method, a comma coating method, a gravure coating method, an air knife coating method, a die coating method, a bar coating method, or a spray coating method. After coating, drying to remove the organic solvent and the like can be performed at 70 to 150 ° C. for about 5 to 30 minutes with a hot air convection dryer or the like.
The photosensitive resin layer 3 is formed by applying and drying the above-described photosensitive resin composition on a base film 4 described later, and the photosensitive resin layer 3 is formed on the conductive layer 2 formed on the support film 1. It can also be formed by laminating so as to be in contact with each other.

The thickness of the photosensitive resin layer 3 varies depending on the use, but it is preferably 1 to 50 μm, more preferably 1 to 30 μm, and further preferably 1 to 15 μm after drying. A thickness of 10 μm is particularly preferable. From the viewpoint of coating on the support film, a thickness of 1 μm or more is preferable, and from the viewpoint of photocurability, 50 μm or less is preferable.

The base film 4 and the surface protective film 5 are laminated so that the photosensitive conductive film of the present invention is in contact with the surface of the photosensitive resin layer 3 opposite to the support film 1 side.

As the base film 4, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyphenylene sulfide (PPS), polycarbonate, polymethyl methacrylate, polystyrene, polyvinyl chloride, polyethylene, polypropylene, polyethylene / polypropylene blend film, polyamide, Examples thereof include polyimide, cellulose acetate, polysulfone, and polyethersulfone. Among these, polyethylene terephthalate, polyethylene naphthalate, or polyphenylene sulfide is preferable from the viewpoints of transparency and heat resistance.

The thickness of the base film 4 is preferably 10 to 200 μm, more preferably 15 to 100 μm, and further preferably 20 to 70 μm. 10 μm or more is preferable from the viewpoint of strength at the time of peeling the surface protective film 5 and the surface protection function, and 200 μm or less is preferable from the viewpoint of handleability and cost. The surface of the base film may be subjected to treatment such as corona discharge, electron beam irradiation, sputtering, and easy adhesion treatment.

The surface protective film 5 has an adhesive formed on the film surface, and an adhesive (adhesive) that can be adhered (adhered) to the base film 4 and peeled off can be used without particular limitation. Specific examples include acrylic adhesives, rubber adhesives, and synthetic rubber adhesives. Among them, an acrylic adhesive that can easily control the adhesive force depending on the composition is preferable.
The surface protective film is commercially available as HITALEX (trade name, manufactured by Hitachi Chemical Co., Ltd.).

The thickness of the surface protective film 5 is preferably 10 to 200 μm, more preferably 50 to 150 μm, and even more preferably 100 to 150 μm. 10 μm or more is preferable from the viewpoint of preventing bending during handling, and 200 μm or less is preferable from the viewpoint of reducing peel strength and improving handleability.

The minimum light transmittance in the wavelength region of 450 to 650 nm of the photosensitive conductive film of the present invention is preferably 80% or more, and more preferably 85% or more. The minimum light transmittance in this case is 80% or more in the laminate of the support film excluding the surface protective film of the photosensitive conductive film, the conductive layer containing conductive fibers, the photosensitive resin layer, and the base film. It is preferable that The surface protective film is for protecting the photosensitive conductive film from scratches and dirt, and for increasing the strength of the film during various treatments, and may be colored because it is not incorporated into the final product.

The total thickness of the photosensitive conductive film of the present invention is preferably 100 to 300 μm, more preferably 100 to 250 μm, still more preferably 120 to 250 μm, and particularly preferably 120 to 220 μm.

FIG. 2 is a schematic cross-sectional view of a transfer type photosensitive conductive film. The transfer type photosensitive conductive film shown in FIG. 2 includes a support film 6, a conductive layer 7 containing conductive fibers provided on the support film 6, and a photosensitive resin layer 8 provided on the conductive layer 7. Have In order to protect the photosensitive resin layer 8, a protective film 9 is preferably provided on the photosensitive resin layer 8.

Each of the support film 6 constituting the transfer type photosensitive conductive film, the conductive layer 7 containing conductive fibers, and the photosensitive resin layer 8 is the same as the details of the photosensitive conductive film described above.

As the protective film, a polyethylene terephthalate film, a polypropylene film, a polyethylene film, or the like can be used. Moreover, you may use the same film as the above-mentioned support body film as a protective film.

As for the protective film 9, it is preferable that the number of fish eyes with a diameter of 80 micrometers or more contained in a protective film is 5 pieces / m < ² > or less. "Fish eye" means that when a material is melted by heat, kneaded, extruded, biaxially stretched, casting method, etc., foreign materials, undissolved materials, oxidized degradation products, etc. It is taken in.

The thickness of the protective film 9 is preferably 1 to 100 μm, more preferably 5 to 50 μm, still more preferably 5 to 30 μm, and particularly preferably 15 to 30 μm. From the viewpoint of preventing the protective film from being broken during lamination, the thickness is preferably 1 μm or more.

The photosensitive conductive film or the transfer-type photosensitive conductive film may be stored as it is in the form of a flat plate, or may be wound around a cylindrical core or the like and stored in the form of a roll.

<Method for producing surface protective film and substrate film with conductive pattern>
Next, the manufacturing method of the surface protection film of this invention and the base film with a conductive pattern of this invention is demonstrated, referring FIG. The exposure conditions and development conditions can be adjusted within the range described in

Patent Document

2 or 3.

Specifically, the conductivity of the photosensitive conductive film including the support film 1, the conductive layer 2 containing conductive fibers, the photosensitive resin layer 3, the base film 4, and the surface protective film 5 in this order. A first exposure step of irradiating the layer and the photosensitive resin layer with an actinic ray L in a pattern from the support film side; and after peeling the support film 1, the conductive layer and the photosensitive resin layer in the presence of oxygen A second exposure step of irradiating a part or all of the unexposed portion in at least the first exposure step with actinic rays L, and the conductive layer 2 and the photosensitive resin layer after the second exposure step. 3 is developed to form a surface protection film and a substrate film with a conductive pattern by a developing step for forming a conductive pattern (see FIGS. 3A to 3D). In the second exposure step, a mask may be used to expose a part of the unexposed portion.

The second exposure step is performed in the presence of oxygen, for example, preferably in the air. Further, the condition of increasing the oxygen concentration may be used. In the presence of oxygen, the surface portion of the photosensitive resin layer is not cured by the influence of oxygen even when irradiated with actinic rays, and the photosensitive resin layer excluding the surface portion is exposed and cured. Therefore, the unexposed portion in the first exposure step is cured except for the surface layer in the second exposure step, and only the surface layer is developed during development. Thereby, the resin cured layer which does not have a conductive film with a conductive pattern is provided on the base film 4, and the level | step difference between a conductive pattern and a base film can be made small.

Subsequently, the transfer type photosensitive conductive film shown in FIG. 2 is peeled off from the produced surface protective film and the base film with a conductive pattern, and the protective film 9 is peeled off. Lamination is performed on the pattern forming surface from the photosensitive resin layer 8 side (see FIG. 3E).

Further, a first exposure step of irradiating actinic light L in a pattern from the support film 6 side of the transfer type photosensitive conductive film (see FIG. 3 (f)), after the support film 6 is peeled off, oxygen is present Under the second exposure step of irradiating a part or all of the unexposed portion in at least the first exposure step of the conductive layer and the photosensitive resin layer with an actinic ray L (see (g) of FIG. 3) ), After the second exposure step, the conductive layer and the photosensitive resin layer are developed to form a conductive layer and a two-layer stack (see FIG. 3H). An up-structured surface protective film and a substrate film with a conductive pattern can be produced.

<Method for producing base film with conductive pattern>
A base film with a conductive pattern having a two-layer stack-up structure can be produced by peeling the surface protective film 5 from the surface protective film having a two-layer stack-up structure and the base film with a conductive pattern (see (i) in FIG. 3). ).

The thickness of the substrate film with a conductive pattern ((i) in FIG. 3) having a two-layer stack-up structure of the present invention is preferably 30 to 100 μm, more preferably 30 to 90 μm, further preferably 40 to 90 μm, and 50 to 80 μm. Is particularly preferred.

The substrate film with a conductive pattern of the present invention can be used as a substrate with a transparent conductive pattern, such as a plasma display panel, an electroluminescence panel, an electrochromic element, a liquid crystal panel, and a touch panel.

Next, an example of the use of the base film with a conductive pattern of the present invention will be described. FIG. 4A is a schematic top view illustrating an example of a capacitive touch panel sensor. The touch panel sensor shown in FIG. 4A has a touch screen 102 for detecting a touch position on one side of a transparent base material 101. This area detects a change in capacitance and is transparent as an X position coordinate. An electrode 103 and a transparent electrode 104 having Y position coordinates are provided. FIG. 4B is a schematic cross-sectional view taken along the line II of FIG. Each of the

transparent electrodes

103 and 104 having the X and Y position coordinates includes a lead wire 105 for connecting to a driver element circuit for controlling an electric signal as a touch panel, and the lead wire 105 and the

transparent electrodes

103 and 104. A connection electrode 106 for connecting the two is disposed. Further, a connection terminal 107 connected to the driver element circuit is disposed at the end of the lead-out wiring 105 opposite to the connection electrode 106.

Hereinafter, the present invention will be specifically described based on examples, but the present invention is not limited thereto.

(Conductive fiber dispersion 1 (Preparation of silver fiber dispersion by polyol method)
In a 2000 ml three-necked flask, 500 ml of ethylene glycol was placed and heated to 160 ° C. with an oil bath while stirring with a magnetic stirrer under a nitrogen atmosphere. A solution prepared by dissolving ₂ mg of PtCl ₂ separately prepared in 50 ml of ethylene glycol was added dropwise thereto. After 5 minutes, a solution in which 5 g of AgNO ₃ was dissolved in 300 ml of ethylene glycol and a solution in which 5 g of polyvinylpyrrolidone having a weight average molecular weight of 40,000 (manufactured by Wako Pure Chemical Industries, Ltd.) was dissolved in 150 ml of ethylene glycol were added dropwise. The solution was dropped from the funnel in 1 minute, and then stirred at 160 ° C. for 60 minutes.

The reaction solution was allowed to stand at 30 ° C. or lower, diluted 10-fold with acetone, centrifuged at 2000 rpm for 20 minutes with a centrifuge, and the supernatant was decanted. Acetone was added to the precipitate, and after stirring, the mixture was centrifuged under the same conditions as described above, and acetone was decanted. Then, it centrifuged twice similarly using distilled water, and obtained the silver fiber. When the obtained silver fiber was observed with an electron microscope, the fiber diameter (diameter) was about 5 nm, and the fiber length was about 5 μm.

[Preparation of silver fiber dispersion]
Silver fiber dispersion 1 was obtained by dispersing 0.2% by mass of the silver fiber obtained above and 0.1% by mass of dodecyl-pentaethylene glycol in pure water.

The materials shown in Table 1 were blended in the blending amounts (unit: parts by mass) shown in the table to prepare a photosensitive resin composition.

Each component in Table 1 is shown below.
Acrylic resin A: methacrylic acid / methyl methacrylate / ethyl acrylate / styrene = 20/50/20/10 mass%, weight average molecular weight 80,000, acid value 130 (manufactured by Hitachi Chemical Co., Ltd.)
PET-30: Pentaerythritol triacrylate (trade name, manufactured by Shin-Nakamura Chemical Co., Ltd.)
IRGACURE OXE 01: 1,2-octanedione, 1-[(4-phenylthio) -phenyl, 2- (o-benzoyloxime)] (trade name, manufactured by BASF Corporation)
SH-30: Octamethylcyclotetrasiloxane (trade name, manufactured by Toray Dow Corning Co., Ltd.)

<Weight average molecular weight of acrylic resin A / GPC measurement conditions>
Model: Hitachi L6000 (pump, manufactured by Hitachi, Ltd.)
Detection: L3300RI (detector, manufactured by Hitachi, Ltd.)
Column: Gelpack GL-R440 + GL-R450 + GL-R400M (manufactured by Hitachi Chemical Co., Ltd.)
Column specifications: Diameter 10.7mm x 300mm
Solvent: THF (tetrahydrofuran)
Sample concentration: 120 mg of a resin solution of NV (non-volatile content concentration) 40% by mass was collected and dissolved in 5 mL of THF. Injection amount: 200 μL
Pressure: 4.9 MPa
Flow rate: 2.05 mL / min

(Example 1)
<Preparation of photosensitive conductive film>
The conductive fiber dispersion 1 was uniformly applied at 25 g / m ² onto a 16 μm-thick polyethylene terephthalate film (trade name “A-1517”, manufactured by Toyobo Co., Ltd.) as a support film 1, and hot air convection at 100 ° C. The conductive layer 2 was formed on the support film 1 (1st film) by drying with a type dryer for 10 minutes, and pressurizing with the linear pressure of 10 kg / cm at room temperature (25 degreeC). The thickness of the conductive layer after drying was about 0.01 μm.

Next, a surface protective film (made by Hitachi Chemical Co., Ltd., trade name “Hitarex”, 175 μm thickness) 5 is a base film of a 50 μm thick polyethylene terephthalate film (made by Toray Film Processing Co., Ltd., trade name “Tough Top”). 4 was laminated at room temperature (25 ° C.) and 0.4 MPa. Then, the prepared photosensitive resin composition is uniformly applied to the surface of the base film 4 opposite to the surface to which the surface protective film 5 is laminated, and dried for 10 minutes in a hot air convection dryer at 100 ° C. Layer 3 was formed. In addition, the film thickness after drying of the photosensitive resin layer was 5 micrometers.
The conductive film 2 and the photosensitive resin layer 3 of the two films obtained as described above are arranged so as to face each other, laminated under the conditions of 120 ° C. and 0.4 MPa, support film 1−conductive layer 2−photosensitive resin layer A photosensitive conductive film constituted in the order of 3-substrate film 4-surface protective film 5 was produced (see FIG. 1).

<Preparation of transfer type photosensitive conductive film>
The conductive fiber dispersion 1 was uniformly applied at 25 g / m ² onto a 16 μm-thick polyethylene terephthalate film (trade name “A-1517” manufactured by Toyobo Co., Ltd.) as the support film 6, and hot air at 100 ° C. The conductive layer 7 was formed on the support film 6 by drying with a convection dryer for 10 minutes and pressurizing at a linear pressure of 10 kg / cm at room temperature. The thickness of the conductive layer after drying was about 0.01 μm.

Next, the photosensitive resin composition is uniformly coated on a 16 μm-thick polyethylene terephthalate film on which the conductive layer 7 is formed, and dried for 10 minutes with a hot air convection dryer at 100 ° C. to be photosensitive resin layer 8. Formed. In addition, the film thickness after drying of the photosensitive resin layer was 5 micrometers.
Next, a 30 μm-thick polyethylene terephthalate film (trade name “ES-201”, manufactured by Oji Film Co., Ltd.) is laminated as a protective film on the above-obtained film under the conditions of room temperature and 0.4 MPa, and the support film 6- A transfer type photosensitive conductive film formed in the order of conductive layer 7 -photosensitive resin layer 8-(photosensitive resin layer protective film 9) was produced.

<Formation of surface protective film using photosensitive conductive film and base film with conductive pattern>
A photomask having a wiring pattern with a line width / space width of 1/1 mm and a length of 120 mm was adhered to the support film 1 of the photosensitive conductive film obtained above. The conductive layer and the photosensitive resin layer were irradiated with light at an exposure amount of 50 mJ / cm ² using an exposure machine having a high-pressure mercury lamp lamp (trade name “EXM-1201” manufactured by Oak Manufacturing Co., Ltd.). Subsequently, the support film 1 was peeled off, and the conductive layer and the photosensitive resin layer were irradiated with light at an exposure amount of 100 mJ / cm ² in an oxygen atmosphere without using a photomask.

After exposure, the film was allowed to stand at room temperature for 15 minutes, and developed by spraying a 1% by mass aqueous sodium carbonate solution at 30 ° C. for 30 seconds. After the development, a conductive pattern having a line width / space width of about 1/1 mm was formed. It was confirmed that the conductive pattern was formed satisfactorily.

<Formation of a base film with a conductive pattern having a two-layer stackup structure using a transfer type photosensitive conductive film>
The surface protection film formed using the photosensitive conductive film and the base film with a conductive pattern are heated at 80 ° C. for 10 minutes to deactivate the polymerization reaction of the photosensitive resin layer 3, and then the transfer form produced above. The protective film 9 of the photosensitive conductive film was peeled off, and the photosensitive resin layer 8 was laminated on a conductive pattern formed using the photosensitive conductive film at 110 ° C. and 0.4 MPa. Next, a photomask having a wiring pattern with a line width / space width of 1/1 mm and a length of 120 mm was adhered to the support film 6 of the transfer type photosensitive conductive film. The conductive layer and the photosensitive resin layer were irradiated with light at an exposure amount of 50 mJ / cm ² using an exposure machine (trade name “EXM-1201” manufactured by Oak Manufacturing Co., Ltd.) having a high-pressure mercury lamp. Subsequently, the support film 6 was peeled off, and the conductive layer and the photosensitive resin layer were irradiated with light at an exposure amount of 100 mJ / cm ² in an oxygen atmosphere without using a photomask.

After exposure, the film was allowed to stand at room temperature (25 ° C.) for 15 minutes and developed by spraying at 30 ° C. with a 1 mass% sodium carbonate aqueous solution for 30 seconds. After the development, a conductive pattern having a line width / space width of about 1/1 mm was formed. It was confirmed that the conductive pattern was formed satisfactorily. From this, it was confirmed that a two-layer electrode could be formed by the photosensitive conductive film and the transfer-type photosensitive conductive film, and a surface protective film having a two-layer stack-up structure and a base film with a conductive pattern were obtained.
Moreover, after peeling off the surface protective film 5 in the conductive pattern laminated base material of the surface protective film of this two-layer stack-up structure and the base film with a conductive pattern, the location where both the conductive layer 2 and the conductive layer 7 are formed Was measured with a Nikon Digi Microhead (MH-15M, manufactured by Nikon Corporation), and the thickness was 60 μm. The total light transmittance measured with a haze meter (NDH-5000, Nippon Denshoku Industries Co., Ltd.) was 88%.

(Comparative Example 1) <Production of double-layer conductive pattern base material by ITO-PET>
A transparent adhesive (trade name “DA-5050” manufactured by Hitachi Chemical Co., Ltd., trade name “DA-5050”) is laminated on ITO-PET (trade name “300R” manufactured by Toyobo Co., Ltd.) at room temperature and 0.4 MPa, and the same is applied thereon. ITO-PET was laminated at room temperature at 0.4 MPa. As a result of measuring this laminate with a Nikon Digi Microhead (MH-15M, manufactured by Nikon Corporation), the thickness was 302 μm. The total light transmittance measured with a haze meter (NDH-5000, Nippon Denshoku Industries Co., Ltd.) was 85%. In the examples, since the thickness was 60 μm, it was shown that the present invention has an effect of thinning a substrate with a conductive pattern having a two-layer stack-up structure (two-layer structure).

According to the conductive pattern forming method of the present invention, it is possible to protect the substrate film from scratches and dirt in the pattern forming step. Further, the touch panel can be made thin by using the photosensitive conductive film and the transfer type photosensitive conductive film in combination.

DESCRIPTION OF SYMBOLS 1 ... Photosensitive conductive film support film, 2 ... Photoconductive conductive film layer, 2a ... Conductive pattern made from photosensitive conductive film, 3 ... Photoconductive resin layer of photosensitive conductive film, 3a ... Photoconductive conductive film 4 ... substrate film, 5 ... surface protective film, 6 ... support film for transfer-type photosensitive conductive film, 7 ... conductive layer for transfer-type photosensitive conductive film, 8 ... transfer-type photosensitive conductive film Photosensitive resin layer, 7a ... conductive pattern formed from transfer-type photosensitive conductive film, 8a ... cured resin layer of transfer-type photosensitive conductive film, 9 ... protective film, L ... actinic ray, 101 ... transparent substrate, 102 ... Touch screen, 103 ... Transparent electrode (X position coordinate), 104 ... Transparent electrode (Y position coordinate), 105 ... Lead-out wiring, 106 ... Connection electrode, 107 ... Connection terminal.

Claims

A photosensitive conductive film comprising a support film, a conductive layer containing conductive fibers, a photosensitive resin layer, a base film, and a surface protective film in this order.
The photosensitive conductive film according to claim 1, wherein the minimum light transmittance in a wavelength region of 450 to 650 nm is 80% or more.
The photosensitive conductive film according to claim 1, wherein the conductive fiber is a silver fiber.
The photosensitive conductive film according to any one of claims 1 to 3, wherein the photosensitive resin layer contains a binder polymer, a photopolymerizable compound having an ethylenically unsaturated bond, and a photopolymerization initiator.
The photosensitive conductive film according to any one of claims 1 to 4, wherein the surface protective film is an acrylic adhesive.
A first exposure step of irradiating the conductive layer and the photosensitive resin layer of the photosensitive conductive film according to any one of claims 1 to 5 with actinic rays in a pattern form from the support film side;
A second exposure step of irradiating a part or all of the unexposed portion in the first exposure step of the conductive layer and the photosensitive resin layer with actinic rays in the presence of oxygen after peeling the support film; ,
The manufacturing method of the surface protection film provided with the image development process which forms a conductive pattern by developing the said conductive layer and the said photosensitive resin layer after said 2nd exposure process, and a base film with a conductive pattern.
A surface protective film and a substrate film with a conductive pattern obtained by the production method according to claim 6 are provided on a support film, a conductive layer containing conductive fibers provided on the support film, and the conductive layer. Laminating the transfer type photosensitive conductive film having the photosensitive resin layer from the photosensitive resin layer side to the conductive pattern side of the surface protective film and the substrate film with a conductive pattern;
A first exposure step of irradiating the conductive layer and the photosensitive resin layer with actinic rays in a pattern from the support film side;
A second exposure step of irradiating a part or all of the unexposed portion in the first exposure step of the conductive layer and the photosensitive resin layer with actinic rays in the presence of oxygen after peeling the support film; ,
A surface protective film having a two-layer stack-up structure and a base film with a conductive pattern comprising a developing step of forming a conductive pattern by developing the conductive layer and the photosensitive resin layer after the second exposure step Manufacturing method.
The method for producing a surface protective film having a two-layer stack-up structure and a base film with a conductive pattern according to claim 7, further comprising removing the surface protective film from the obtained surface protective film and the base film with a conductive pattern. A method for producing a base film with a conductive pattern having a two-layer stack-up structure.
The photosensitive conductive film according to any one of claims 1 to 5, which is used in the method for producing a substrate film with a conductive pattern according to claim 7 or 8, a support film, and provided on the support film. A conductive film set with a transfer type photosensitive conductive film having a conductive layer containing conductive fibers and a photosensitive resin layer provided on the conductive layer.