KR20130028079A - Transparent conductive film,transparent conductive laminate, and touch panel - Google Patents

Abstract

Even when two sheets of transparent conductive films are laminated, an object of the present invention is to provide a transparent conductive film that can maintain excellent colorless transparency and that can easily form a patterned electrode portion.
The transparent conductive film according to the present invention is characterized in that a transparent low refractive index layer having a cerium oxide layer refractive index of 1.4 or less and less than 1.7 and a transparent conductive layer are sequentially formed on one side of the transparent film substrate. It is preferable that the said transparent low refractive index layer is a thin film layer which consists of a silicon oxide, and it is preferable that the said transparent conductive layer is a thin film layer which consists of ITO.

Description

Transparent conductive film, transparent conductive laminated body, and touch panel {TRANSPARENT CONDUCTIVE FILM, TRANSPARENT CONDUCTIVE LAMINATE, AND TOUCH PANEL}

The present invention relates to a transparent conductive film that can be used as a low resistance transparent electrode used in a touch panel, and more particularly, to a transparent conductive film suitable for use as a capacitive touch panel. Moreover, it is related with the transparent conductive laminated body which consists of two said transparent conductive films, and the touchscreen provided with the said transparent conductive film or a transparent conductive laminated body.

In recent years, with the expansion of the touch panel market, development of a transparent conductive film that can be used as a low resistance transparent electrode of a touch panel is being progressed. For example, Patent Document 1 discloses a resistive film layer 2 made of a transparent conductive metal oxide, a thin film layer 3 made of silicon dioxide, and a resistive film layer 4 made of a transparent conductive metal oxide. An electrode member (transparent conductive film) for a resistive film-type transparent touch panel, which is laminated in the order of 1), (2), (3) and (4), is described.

As the transparent conductive metal oxide, an indium oxide thin film, a thin film (ITO thin film) doped with indium oxide and the like can be used, and the same type of transparent conductive metal oxide is used for the resistive film layer 2 and the resistive film layer 4. It is also described that it is preferable to use.

In addition, Patent Document 2 discloses a transparent conductive film suitable for a capacitive touch panel.

As a transparent conductive film in which the 1st transparent dielectric layer, the 2nd transparent dielectric layer, and the transparent conductive layer were formed in this order in the one or both surfaces of the transparent film base material from the said transparent film base material side,

The transparent conductive layer is patterned,

When the refractive index of the first transparent dielectric layer is n1, the refractive index of the second transparent dielectric layer is n2, and the refractive index of the transparent conductive layer is n3, the relationship of n2 <n3 <n1 is satisfied,

The first transparent dielectric layer has a thickness of 2 nm or more and less than 10 nm,

The thickness of the second transparent dielectric layer is 20-55 nm,

The transparent conductive film whose thickness of the said transparent conductive layer is 15-30 nm is disclosed.

The first transparent dielectric layer is preferably made of a composite oxide containing at least indium oxide and cerium oxide, the second transparent dielectric layer is preferably formed of SiO ₂ , and is oxidized as a constituent material of the transparent conductive layer. It is disclosed that indium oxide (ITO) containing tin and the like are preferably used.

When the electrode member (transparent conductive film) for the resistive film-type transparent touch panel of the said patent document 1 is used, it is described that especially a transparency and pen durability can be improved and a higher quality and high performance touch panel can be provided.

In the case of using the transparent conductive film of Patent Document 1 as a resistive touch panel having a surface resistivity of 200 to 250 Ω / □, since the thickness of the resistive layer (transparent conductive layer) is relatively thin, two transparent conductive films are used. Since a spacer exists between them, the yellow taste mainly resulting from a transparent conductive layer does not become a problem very much. However, when using the transparent conductive laminated body which laminated | stacked two transparent conductive films like a capacitive touch panel, yellow taste becomes strong and there exists a problem that it cannot use for practical use.

In particular, as the area of a capacitive touch panel increases in recent years, the responsiveness when a user touches a finger on the touch panel becomes worse. Therefore, in order to prevent the deterioration of the responsiveness, it is preferable to lower the surface resistivity to 200 Ω / □ or less, preferably 150 Ω / □ by thickening the transparent conductive layer while maintaining the overall light transmittance of the touch panel at 85% or more. Although attempts have been made, a problem arises that the yellowishness becomes stronger as the transparent conductive layer becomes thicker.

In the conventional transparent conductive film represented by the transparent conductive film of patent document 1, as shown to FIG. 5A, several transparent layers are normally laminated | stacked on the transparent film base material 1 ', and the outermost layer is transparent conductive Layer 4 '. In the transparent conductive film used in the capacitive touch panel, as shown in FIG. 5B, at least the transparent conductive layer 4 'is partially removed to form the patterned electrode portion 4'P. It is necessary to do Here, a pattern-shaped electrode part means the part in which the transparent conductive layer of the outermost layer of a transparent conductive film is formed in desired shape, such as a grid | lattice form and a checkered pattern shape. In addition, parts other than an electrode part are the parts (non-electrode part) in which the layer containing conductive materials, such as a transparent conductive layer, is not formed at least.

Referring to FIG. 1 and FIG. 2 showing the transparent conductive film and the transparent conductive laminate according to the present invention in more detail, the capacitive touch panel is electrically in the X direction, as shown in FIG. The transparent conductive film (right side) which has the patterned electrode part 4Px connected, and the transparent conductive film (right side) which has the patterned electrode part 4Py electrically connected to the Y direction are adhere | attached with a transparent adhesive, and transparent conductive laminated Use as a sieve. In addition, in FIG. 1C, although the pattern-shaped electrode part 4Px electrically connected to the X direction and the pattern-shaped electrode part 4Py electrically connected to the Y direction are shown by different colors, this is shown in FIG. As shown in 2, when two transparent conductive films are laminated | stacked and the transparent conductive laminated body is comprised, the raw material itself is the same as classification for convenience for making it easy to grasp | ascertain the positional relationship between electrode parts.

In FIG. 2, A is a top view of a transparent conductive laminated body, B is sectional drawing in the line B-B in A, C is an enlarged view of the part enclosed by the circle C in A. As shown in FIG. As shown in FIG. 2, in the transparent conductive laminated body used for a capacitive touch panel, it has a transparent conductive film which has a patterned electrode part electrically connected to the X direction, and has a patterned electrode part electrically connected to the Y direction. When overlapping the transparent conductive film, basically, the electrode portions formed on each transparent conductive film (that is, 4Px and 4Py) are laminated so as not to overlap. In reality, however, a portion O of the electrode portions 4Px and 4Py formed on the transparent conductive film of the upper layer and the transparent conductive film of the lower layer overlaps vertically. For this reason, when the surface of a transparent conductive laminated body is seen from the front, it becomes a problem because the yellow taste of the overlapping part 0 becomes conspicuous (refer FIG. 2C).

Hereinafter, in this specification, the part in which electrode parts mutually overlap is an electrode part formed in the transparent conductive film of an upper layer and the transparent conductive film of a lower layer in a transparent conductive laminated body or a capacitive touch panel using the same as mentioned above. (4Px and 4Py) means the part which overlaps up and down, In this specification, a yellow rice means the yellow color of the part which the said electrode part mutually overlaps.

Since the touch panel covers the display screen, high colorless transparency is required so that the display screen can be clearly seen.

In order to use a touch panel (especially a large area capacitive touch panel) for practical use in terms of yellow color, it is preferable that b * of the part where the electrode portions overlap each other in the touch panel is +2.5 or less, and it is +2.0 or less. (B * is a value indicating a position between yellow and blue in the CIE L * a * b * color space, with a negative value near blue and a positive value near yellow.)

In order to achieve this requirement, a material which is basically colorless and transparent is used as the material used for each layer constituting the transparent conductive film, but there is also a problem that yellowing occurs because light of a specific wavelength is absorbed.

The invention of Patent Literature 2 provides a transparent conductive film suitable for a capacitive touch panel. In a transparent conductive film having a transparent conductive layer patterned, a difference between a pattern portion (electrode portion) and a pattern opening portion (non-electrode portion) is provided. Is suppressed, and a transparent conductive film having a good visual quality can be obtained. In particular, like a capacitive touch panel, a touch panel for forming a patterned transparent conductive layer (electrode portion on a pattern) on the entire surface of the display display portion As appropriate.

However, also by the transparent conductive film of patent document 2, when laminating two films, the problem that a yellow taste becomes strong does not solve.

In the transparent conductive films disclosed in Patent Documents 1 and 2, both layers are formed on the film substrate, but according to the configuration disclosed in the Examples, the first layer (in the above three layers, the film substrate Since ITO is included in either the layer closest to the layer) and the third layer (the outermost layer), even if only the third layer of the ITO layer is removed by etching and the electrode portion in the pattern form is formed, it is energized through the first layer containing ITO. Has a problem. Therefore, in order to prevent an unwanted electricity supply, it is necessary to remove all of the 1st layer-3rd layer, and a special etching technique is needed and there existed a problem that additional cost was added.

Japanese Patent No. 4121191 Japanese Laid-Open Patent Publication No. 2010-23282

Therefore, the present invention is not only used in one sheet, but also in the case of using two sheets, especially when two transparent conductive films are laminated on glass, such as a capacitive touch panel, b * of +2.5 or less An object of the present invention is to provide a transparent conductive film that can maintain a value and that can easily form a patterned electrode portion.

MEANS TO SOLVE THE PROBLEM As a result of earnestly examining in order to solve the said subject, it turned out that the transparent conductive film obtained by forming a cerium oxide layer, a transparent low refractive index layer, and a transparent conductive layer sequentially on one side of a transparent film base material has the desired electroconductivity. The present inventors have found that a low b * value is maintained even when two sheets are laminated or two sheets are laminated on glass, thereby completing the present invention.

That is, a cerium oxide layer, a transparent low refractive index layer having a refractive index of 1.4 to less than 1.7 and a transparent conductive layer are sequentially formed on one surface of the transparent conductive film and the transparent film substrate according to the present invention.

It is preferable that the said transparent low refractive index layer is a thin film layer which consists of a silicon oxide, Furthermore, it is preferable that the said silicon oxide thin film layer was formed by the chemical vapor deposition method (CVD method).

Moreover, it is preferable that the said transparent conductive layer is a thin film layer which consists of ITO.

In addition, it is preferable that a polyester anchor coating layer exists between the transparent film base material and the cerium oxide layer.

The thickness of the cerium oxide layer is preferably 5 to 200 nm, the thickness of the transparent low refractive index layer is preferably 5 to 200 nm, and the thickness of the transparent conductive layer is preferably 10 to 500 nm.

The transparent conductive film may be formed with lead wires and / or patterned electrode parts. Two transparent conductive films in which the lead-out wiring and the patterned electrode portion are formed are stacked together, adhered with a transparent pressure-sensitive adhesive layer, and are suitable for use as a transparent conductive laminate.

The transparent conductive film is suitable for use in a touch panel, and in particular, the transparent conductive laminate is suitable for use in a capacitive touch panel.

The transparent conductive film of the present invention has a suitable electrical property as a transparent conductive film for a touch panel, and is hardly yellow even when two sheets are stacked. For this reason, the transparent conductive film of the present invention is particularly suitable for use in capacitive touch panels in which a plurality of transparent conductive films are laminated.

1 is a view schematically showing an example of a transparent conductive film according to the present invention, A is a cross-sectional view of a transparent conductive film, B is a cross-sectional view of a transparent conductive film having a patterned electrode portion, C is electrically connected to the X direction It is a top view of the transparent conductive film (left side) which has a patterned electrode part, and the transparent conductive film (right side) which has a patterned electrode part electrically connected to the Y direction.
FIG. 2 is a diagram schematically showing the transparent conductive laminate of the present invention formed by bonding two transparent conductive films of FIG. 1 with a transparent pressure-sensitive adhesive layer, wherein A is a plan view, B is a line BB sectional view in A, and C is A It is an enlarged view of the part enclosed by circle C in the figure.
FIG. 3 shows a touch panel of the present invention (however, the drawing wirings are not shown in the figure) formed by bonding the transparent conductive laminate and the glass of FIG. 2 to each other with a transparent pressure-sensitive adhesive layer.
4 is a diagram schematically showing another example of the transparent conductive film according to the present invention, where A is a sectional view of the transparent conductive film, and B is an enlarged view of a portion surrounded by circle B in A. FIG.
5 is a view schematically showing a transparent conductive film (transparent conductive film containing a conductive material in the first and third layers) according to the prior art, wherein A is a sectional view of the transparent conductive film, and B is a third layer ( (Most outermost layer) is an enlarged view of a portion partially removed by etching, and a portion enclosed by a circle, the arrow in the enlarged view indicates the flow of electricity, and C is a partial removal of all of the first to third layers by etching. The state which formed the electrode part of a pattern form is shown.

As shown in A of FIG. 1, the transparent conductive film 5 of the present invention has at least a cerium oxide layer 2, a transparent low refractive index layer 3, and a transparent conductive layer 4 on the transparent film substrate 1. ) Has a stacked structure sequentially. The transparent film base material 1 and the three layers 2-4 are one transparent conductive film, and may have transparency of about 80% or more (preferably 85% or more) of the total light transmittance.

In addition, in the transparent conductive film of this invention, a refractive index means the refractive index with respect to the light of wavelength 550nm, and can measure it by a spectral reflection spectrum measurement. In addition, the thickness of each layer means a physical thickness and can be measured by a fluorescent X-ray analyzer.

Although the transparent film base material 1 used for the transparent conductive film of this invention can use transparent plastic films, such as a polyethylene terephthalate film, a polyethylene naphthalate film, a polypropylene film, an acrylic film, a polycarbonate film, and a fluorine film, Among them, polyethylene terephthalate films are preferred in terms of heat resistance and the like.

As shown in FIG. 4, the transparent hard coat layer 10 made of resin may be formed on one side or both sides of the transparent plastic film 9 (FIG. 4 shows the hard coat layer formed on both sides of the transparent plastic film). An example is shown). Thus, the hard coat layer formed on one side or both sides is also included in the transparent film substrate 1 according to the present invention.

By forming the hard coating layer on the surface of the transparent plastic film, it is possible to fill in the defects inherent in the transparent plastic film and to improve the slipperiness and surface strength of the surface of the transparent film substrate on which the hard coating layer is formed. Scratches can be prevented from occurring in the film base material. In particular, in the case where the hard coat layer is formed on the transparent plastic film surface on the transparent conductive layer side, in addition to the above point, the conductivity of the transparent conductive film of the present invention can be further stabilized.

The resin used for the hard coating layer is preferably a hard coating layer of 2H or more of pencil hardness, transparent resins such as melamine resin, ultraviolet curable acrylic resin, urethane resin, and the like, and the thickness is preferably 1 to 7 µm. .

In addition, when the hard coating layer is formed, an interference fringe may be generated. In this case, an interference prevention layer made of a resin and high refractive index fine particles or the like between the transparent plastic film and the hard coating layer (thickness of about 10 to 50 nm, preferably Is preferably about 20 to 30 nm). As said resin, acrylic resin, polyester resin, etc. can be used, for example, As said high refractive index microparticles | fine-particles, the microparticles which consist of titanium oxide, zirconium oxide, etc. can be used, for example.

Thus, it is also included in the transparent film substrate according to the present invention to have an interference prevention layer between the transparent plastic film and the hard coating layer.

10-300 micrometers is preferable, as for the thickness of the transparent film base material 1, 50-260 micrometers is more preferable, 50 micrometers-200 micrometers are especially preferable.

When thickness is thinner than 10 micrometers, especially when it uses for a touchscreen, since the strength of a plastic film is not enough when inputting with a finger, a pen, etc., the deformation | transformation of a transparent conductive film becomes large too much, and the transparent conductive layer 4 It is not preferable because cracks occur, and as a result, surface resistivity becomes unstable. Further, curling occurs in the transparent conductive film, and as a result, workability deteriorates in post-working such as bonding the transparent conductive film to the touch panel, which is not preferable.

On the other hand, when the thickness is thicker than 300 µm, when used in a resistive touch panel, when the input using a finger or a pen, etc., a load is applied to the transparent conductive film by contacting the transparent conductive film to be applied. There is a problem that must be done. Moreover, since the cost of a transparent conductive film rises, it is unpreferable.

The cerium oxide layer 2 formed on the transparent conductive film of this invention is a layer closest to the transparent film base material 1 among three layers 2-4. The cerium oxide layer 2 is a transparent high refractive index layer, and its refractive index is 1.7 or more and less than about 2.5 (more preferably 2.0 to 2.2), and the refractive index is higher than that of the adjacent transparent low refractive index layer 3. Thus, it is thought that transparency is improved by laminating | stacking two layers 2 and 3 in which the refractive indexes of light differ from each other. In particular, the difference in refractive index between the cerium oxide layer 2 and the transparent low refractive index layer 3 is preferably 0.2 or more. Moreover, by using the said cerium oxide layer, compared with the case where transparent high refractive index layers other than a cerium oxide layer are used, the reinforcement of yellowishness at the time of overlapping two transparent conductive films is suppressed.

The thickness of the cerium oxide layer 2 is preferably 5 nm to 200 nm. If the thickness is less than 5 nm, the characteristics as the transparent high refractive index layer are not sufficiently exhibited, and the difference in refractive index with the transparent low refractive index layer 3 becomes small, and serves as a transparent high refractive index layer (by being used together with the transparent low refractive index layer). It is not preferable to increase transparency) because it cannot be achieved sufficiently. On the other hand, if it exceeds 200 nm, cracks are likely to occur due to film stress, which is not preferable.

Further preferred cerium oxide layer 2 has a thickness of 10 nm to 50 nm.

Cerium oxide (cerium oxide) is represented by Ce0 ₂ in the theoretical compositional formula, and in the present invention, the element ratio of Ce and O is preferably 1: 2. However, the element ratio of Ce and O does not necessarily have to be strictly 1: 2, and the element ratio of Ce and O is somewhat larger or smaller (specifically, in the composition formula CeOx, x is 1.6 to 2.1). It is also included in the cerium oxide used in the transparent conductive film of the present invention. In the present specification, CeO ₂ (1.6 ≦ x ≦ 2.1) is represented by CeO ₂ .

The transparent low refractive index layer 3 formed on the transparent conductive film of the present invention is formed between the cerium oxide layer 2 and the transparent conductive layer 4, and serves to improve the transparency of the transparent conductive film of the present invention. will be.

In order to play the said role, it is preferable that refractive index is 1.4 or more and less than 1.7 (more preferably 1.4-1.5), and it is preferable that thickness is 5-200 nm.

If the thickness is less than 5 nm, the characteristics as the transparent low refractive index layer are not sufficiently exhibited, and the difference in refractive index with the cerium oxide layer 2 becomes small, and serves as the transparent low refractive index layer (transparency by use with the transparent high refractive index layer). It is not preferable because it will not be possible to achieve sufficiently.

On the other hand, if it exceeds 200 nm, cracks are likely to occur due to film stress, which is not preferable. The thickness of the more preferable transparent low refractive index layer is 10 nm-50 nm.

The transparent low refractive index layer 3 is not particularly limited as long as it is a transparent layer that satisfies the range of the refractive index and the thickness. Inorganic compounds such as an inorganic oxide thin film layer such as a silicon oxide (Si0 ₂ ) thin film layer and a magnesium fluoride (MgF ₂ ) thin film layer A thin film layer made of a resin such as a thin film layer, a fluorine resin or a silicone resin can be used.

In particular, it is preferable to make the transparent low refractive index layer 3 a silicon oxide thin film layer from the point of heat resistance and moisture heat resistance.

In addition, silicon oxide, but the (silicon oxide) is in the theoretical formula is expressed as SiO _2, be Si and O source is strictly one consumption: need not 2, in the range satisfying the above refractive index, the Si and O It is also included in the silicon oxide used for the transparent conductive film of this invention that element ratio becomes a little big or becomes small (specifically, x should be in the range of 1.6-2.1 in composition formula SiOx). In the present specification, SiO ₂ (1.6 ≦ x ≦ 2.1) is represented as SiO ₂ .

In addition, if the transparent low refractive index layer 3 is made of an electrically insulating material (the inorganic oxide thin film layer, the inorganic compound thin film layer, the resin thin film layer, etc.), the layer to be etched and removed when forming the patterned electrode portion is transparent. Since only the conductive layer is used, the time and cost required for etching can be reduced. That is, in the transparent conductive film of the present invention, since the layer closest to the transparent film base material 1 is the cerium oxide layer 2 having electrical insulation properties, the transparent low refractive index layer 3 also includes an electrical insulation material. The layer which needs formation of the patterned electrode part becomes only the transparent conductive layer 4. However, the present invention is not limited to the transparent low refractive index layer and the electrical insulation used in the present invention, and may be a conductive polymer such as polythiophene-based, polyaceylene-based, polyaniline-based, polypyrrole-based, or the like within the range satisfying the refractive index. It may be a conductive resin thin film layer in which transparent conductive fine particles such as ITO or tin oxide are mixed in the resin. When a transparent low refractive index layer has electroconductivity, when forming a patterned electrode part, it is necessary to also remove this layer by etching.

The transparent conductive layer 4 formed on the transparent conductive film of the present invention is a layer formed on the outermost layer of the transparent conductive film. The transparent conductive layer 4 is made of a thin film of transparent conductive metal oxide, and serves to impart conductivity to the transparent conductive film of the present invention. To do.

As a transparent conductive metal oxide thin film used for the transparent conductive layer 4, conventional transparent conductive films, such as an indium oxide thin film, a tin oxide thin film, a zinc oxide thin film, a cadmium oxide thin film, and a thin film (ITO thin film) doped with indium oxide (ITO thin film) The conductive metal oxide thin film used as the transparent conductive layer of can be used.

Especially, the ITO thin film which is excellent in electroconductivity is especially preferable.

The transparent conductive layer 4 plays a role of determining most of the surface resistivity of the transparent conductive film of the present invention. The surface resistivity is preferably about 5 to 1000 Ω / □, more preferably 200 Ω / □ or less. .

Moreover, the thickness of the transparent conductive layer 4 should just be the thickness which has the said surface resistivity, and although it depends also on the kind of metal oxide thin film layer to be used, about 10 nm-500 nm are preferable.

If the thickness is thinner than 10 nm, the surface resistivity tends to be difficult to be stabilized, which is not preferable because the desired conductivity cannot be obtained stably.

On the other hand, when the thickness is thicker than 500 nm, cracks may occur in the transparent conductive layer 4 due to the film stress, and the conductivity may deteriorate, which is not preferable.

The thickness of the more preferable transparent conductive layer 4 is 15 nm-100 nm.

As a method for forming the cerium oxide layer 2, the transparent low refractive index layer 3, or the transparent conductive layer 4, a conventionally known forming method can be used, and a vapor deposition method such as vacuum deposition, sputtering deposition, electron beam deposition, CVD, Coating methods such as a sol-gel method and the like can be used.

In particular, when the transparent low refractive index layer 3 is a silicon oxide layer, by the CVD method, it is possible to further lower the b * value of the portion where the electrode portions overlap each other in the touch panel.

This is because when the silicon oxide layer is formed by the CVD method, the cerium oxide layer 2 on the silicon oxide layer side is oxidized, so that the degree of oxidation of the cerium oxide layer 2 is higher on the silicon oxide layer side than on the transparent film substrate side, As a result, it is considered that the total light transmittance of the cerium oxide layer 2 becomes high.

In addition, in order to use the transparent conductive film of the present invention in a capacitive touch panel, a lead-out wiring may be formed. The lead-out wiring is a thin wire shown as symbol 8 in FIG. 1C, which is made of metal, and is usually provided only at the outer peripheral portion of the transparent conductive film. The lead-out wiring is conventionally formed by patterning a transparent conductive layer and then printing silver paste (screen printing, etc.), but in recent years, it has recently been formed on both ends of a transparent conductive film on the left side of FIG. In order to narrow the width | variety of the drawing wiring 8, the method of forming a finer drawing wiring by forming a thin film of copper or copper alloy on a transparent conductive layer, and then etching is adopted.

For example, as a method of forming a drawing wiring made of copper by etching, a copper layer is laminated on the entire surface by a sputtering deposition method on a transparent conductive layer, and a resist material is applied thereon in the shape of the drawing wiring, and the resist The copper layer in the portion where the material is not applied is removed by etching, and only the copper layer in the portion where the resist material is applied is left, and then the resist material is removed to remove lead wiring made of copper on the transparent conductive layer. And a method of forming the compound. Withdrawal wiring generally requires a surface resistance of less than 0.4Ω / □. In order to achieve the surface resistance value of 0.4 ohms / square or less in copper lead-out wiring, it is preferable to make thickness of copper 100 nm or more.

Moreover, in order to use the transparent conductive film of this invention for a capacitive touch panel, at least the transparent conductive layer 4 can also be formed as a patterned electrode part electrically connected to the X direction or the Y direction.

Moreover, in order to make it possible to use not only a touch panel but also for transparent electrodes, such as a solar cell and organic EL, you may form the circuit which made the transparent conductive layer 4 into a circuit at least.

As a method of forming a patterned electrode part and a circuit, the etching using a chemical | medical agent or a laser, and the method of using a water-soluble resin layer are mentioned.

For example, in the method of forming a patterned electrode portion by etching, the cerium oxide layer 2, the transparent low refractive index layer 3, and the transparent conductive layer 4 are sequentially formed on the entire surface on a transparent film substrate. After that, a resist material is applied onto the transparent conductive layer 4 in the form of a patterned electrode portion and treated with an etching solution (solutions such as ferric chloride solution, iodic acid solution, hydrochloric acid, agate, and oxalic acid solution). For the portion (where the non-electrode portion) is not coated, only the transparent conductive layer 4 is removed (that is, the cerium oxide layer 2 and the transparent low refractive index layer 3 remain). The above-mentioned three layers (2 to 4) are left in the part (part to be an electrode part) to which the resist material is applied. Subsequently, by removing the resist material, the cerium oxide layer 2 and the transparent low refractive index layer 3 are formed on the entire surface on the transparent film base material, and the pattern shape of the transparent conductive layer 4 is formed thereon. The transparent conductive film of the present invention having an electrode portion may be manufactured.

Moreover, since the transparent conductive film which concerns on this invention has three layers on a transparent film base material, although it is common to the transparent conductive film of patent document 1 and patent document 2, the Example of patent document 1 and patent document 2 In the transparent conductive film described in the above, since the ITO, which is a conductive material, is contained in the layer (first layer) closest to the film base material, only the outermost layer (the third layer; the conductive layer) of the transparent conductive film is etched. Energized through (see FIG. 5B). Therefore, although it is necessary to remove all from the 1st layer to the 3rd layer (refer FIG. 5C), the transparent conductive film of this invention needs a special etching technique and costs are needed to remove it to the 1st layer. In the first layer, since the first layer is made of cerium oxide having no conductivity, it is not necessary to remove the entire layer by etching, and the formation of the patterned electrode portion by etching can be performed in a short time and low cost. In particular, when the second layer of low refractive index layer 3 is made of a material having electrical insulation such as SiO ₂ , only the third layer of transparent conductive layer 4 may be etched and removed. Formation of the electrode portion can be performed further in a short time and low cost.

Moreover, as a method of forming a patterned electrode part using a water-soluble resin layer, for example, a water-soluble resin layer is formed in the one side of a transparent film base material (part to become a non-electrode part) other than the part which forms an electrode part, From there, the cerium oxide layer 2, the transparent low refractive index layer 3, and the transparent conductive layer 4 are sequentially formed on the entire surface, and then immersed in water, such as the water-soluble resin layer and the water-soluble water. The method of removing the said 3 layers 2-4 on a ground layer and leaving the said 3 layers 2-4 of the part (part to become an electrode part) in which the water-soluble resin layer is not formed is mentioned. Also by this method, the transparent conductive film of this invention provided with the patterned electrode part which consists of a cerium oxide layer 2, the transparent low refractive index layer 3, and the transparent conductive layer 4 on the single side | surface of a transparent film base material can be manufactured. Can be.

In addition, in the transparent conductive film of the present invention, not only the film in which the three layers (2 to 4) are laminated on the entire surface on one side of the transparent film base material, but also as described above, the patterned electrode portion is formed, or the lead-out wiring. This is also included.

The transparent conductive film of the present invention in which the lead-out wiring and the patterned electrode portion are formed is particularly suitable when two sheets are used as a transparent conductive laminate. Such a transparent conductive laminate has a non-conductive treatment surface (that is, a surface on the transparent film substrate 1 side) of an upper transparent conductive film, and a conductive treatment surface (that is, a transparent conductive layer 4 side of a lower transparent conductive film). It can manufacture by laminating | stacking so that the surface of ()) may face and adhering by a transparent adhesive layer.

As a transparent adhesive used for a transparent adhesive layer, the normal transparent adhesive used in order to adhere | attach a transparent conductive film in the said field can be used. For example, it is transparent adhesives, such as an acrylic adhesive and a polyether adhesive. It is preferable that a transparent adhesive layer is formed so that it may become a uniform layer interposed between two transparent conductive films. In order to form a uniform layer, it is preferable to transfer the transparent adhesive layer to a transparent conductive film by using a commercially available high-transparent adhesive (0CA) transfer sheet in which a uniform transparent adhesive layer is formed between two plastic sheets. desirable.

As the touch panel of the present invention, a capacitive touch panel using the transparent conductive laminate is particularly preferable, and the capacitive touch panel is, for example, a transparent adhesive layer in which a glass substrate and the transparent conductive laminate are described. By connecting the lead-out wiring and the terminal and connecting the touch panel control driver (semiconductor, etc.) through the flexible printed wiring.

The transparent conductive film of the present invention is not less than +2.5 when not only overlapped with two sheets to form a transparent conductive laminate, but also when the transparent conductive laminate is arranged on a glass substrate like an actual capacitive touch panel. The * value (the lower limit is not particularly limited, but generally -3.0) can be achieved. In addition, b * value can be measured with a color difference meter.

As described above, in the case where the transparent conductive film of the present invention is used in a capacitive touch panel, it is necessary to adhere the other transparent conductive film or the glass substrate by the transparent adhesive layer. In the case of low adhesiveness (adhesiveness) between the transparent film base material / cerium oxide layer / transparent low refractive index layer / transparent conductive layer which comprise a transparent conductive film, there exists a problem that peeling becomes easy to occur.

In particular, when the lead-out wiring is made of copper, since the adhesiveness with the transparent adhesive is high, as a result, the transparent conductive film is strongly adhered to other members, resulting in peeling in the transparent conductive film (particularly, the transparent film base material and cerium oxide). Peeling between layers) easily occurs.

In order to solve this problem, it is necessary to improve the adhesiveness between the transparent film base material and the cerium oxide layer, but in the present invention, as shown in FIG. 4, the polyester is formed between the transparent film base material 1 and the cerium oxide layer 2. By forming the system anchor coating layer 11, the adhesiveness between a transparent film base material and a cerium oxide layer can be improved, maintaining the total light transmittance and b * value in a desired range.

In the case of forming the polyester anchor coating layer, it is more preferable that the transparent film base material has a hard coating layer on at least the side of the side on which the cerium oxide layer is formed. In other words, it is more preferable to form the polyester anchor coating layer on the hard coating layer.

The polyester anchor coating layer can be formed by curing, for example, a hydroxyl group-containing polyester resin with a curing agent reacting with a hydroxyl group. Examples of the hydroxyl group-containing polyester resin include polyester polyols, and examples of the curing agent include polyisocyanates and / or polyisocyanate prepolymers.

Although the adhesion between the transparent film base material and the cerium oxide layer is estimated to be lowered by moisture, the polyester-based anchor coating layer formed by curing the polyester polyol and the polyisocyanate and / or polyisocyanate prepolymer has excellent water resistance. Therefore, stable adhesion can be achieved without changing over time. Moreover, since it is excellent in heat resistance, it is hard to be influenced by the heat which generate | occur | produces in each film forming process (formation process of a cerium oxide layer, a transparent low-refractive-index layer, and a transparent conductive layer) performed after polyester-type anchor coating layer formation (whitening resulting from heat) Hard to crack or).

Moreover, as an example of a preferable polyisocyanate and / or polyisocyanate prepolymer, IPDI type, XDI type, HDI type polyisocyanate and / or polyisocyanate prepolymer are mentioned. By using these, the polyester anchor coating layer which is hard to yellow can be formed. Here, IPDI system means isophorone diisocyanate and its modified form, XDI system means xylylene diisocyanate and its modified form, and HDI system means hexamethylene diisocyanate and its modified form. Examples of the modified form include trimethylolpropane (TMP) adducts, isocyanurate bodies, biuret bodies, and allophanate bodies.

The thickness of the polyester anchor coating layer is preferably 5 to 100 nm. If the thickness exceeds 100 nm, there is a fear that the b * value of the transparent conductive film (or transparent conductive laminate or touch panel) cannot be maintained in a desired range. On the other hand, if it is less than 5 nm, the adhesiveness of a transparent film base material and a cerium oxide layer cannot fully be improved.

Moreover, the transparent conductive film of this invention can also be used for touch panels other than a capacitance type, For example, when it is set as a resistive touch panel, the transparent conductive layer formed in the glass surface, and the transparent conductive of this invention By interposing a dot spacer and forming a lead-out wiring at the end, between the transparent conductive layers of the film facing each other, or between two transparent conductive films of the present invention arranged so as to face each other. Can be configured. The transparent conductive film used at this time may be a patterned electrode part or may not be formed.

Example

Hereinafter, although an Example is used and this invention is demonstrated in detail, this invention is not limited to an Example.

[ Example  1] Transparent conductive film (transparent film base / CeO ₂ layer/ SiO ₂ layer( CVD ) / ITO Manufacture of layers)

On both sides of the 125-micrometer-thick polyethylene terephthalate film (transparent plastic film), the transparent hard coat layer of thickness 2micrometer which consists of acrylic resin was formed by the reverse coating method, and the double-sided hard coat film (transparent film base material) was produced.

Next, a CeO ₂ thin film layer (transparent high refractive index layer refractive index: 2.1), which is a cerium oxide layer having a thickness of 17 nm, was formed on one side of the double-sided hard coat film by vacuum deposition using Ce as a raw material.

Next, hexamethyldisiloxane was used as a raw material and oxygen gas was used as a reaction gas, and a 40 nm-thick SiO ₂ thin film layer (transparent low refractive index layer refractive index: 1.5) was formed by chemical vapor deposition (CVD).

Next, an ITO thin film layer (transparent conductive layer) having a thickness of 30 nm was formed by sputtering deposition using ITO as a raw material, to prepare a transparent conductive film of the present invention.

Moreover, each said layer was formed in the whole surface on the single side | surface of a transparent film base material (double-sided hard coat film).

[ Example  2] Transparent conductive film (transparent film base / CeO ₂ layer/ SiO ₂ layer( Sputtering ) / ITO Manufacture of layers)

In the same manner as in Example 1, except that a SiO ₂ thin film layer having a thickness of 40 nm was formed by sputtering deposition instead of the CVD method of Example 1 using Si as a raw material, argon gas as a process gas, and oxygen gas as a reaction gas. On one side of the transparent film base material (double-sided hard coat film), a CeO ₂ layer (transparent high refractive index layer refractive index: 2.1), a SiO ₂ thin film layer (transparent low refractive index layer refractive index: 1.5), and an ITO layer (transparent conductive layer) A transparent conductive film of the present invention formed sequentially was prepared.

The process gas is a gas for producing a plasma used for sputtering (colliding the raw materials), and the reaction gas is a gas for reacting with the sputtered raw material.

[ Comparative example  1] Transparent conductive film (transparent film base / ITO layer/ SiO ₂ layer( Sputtering ) / ITO Manufacture of layers)

The transparent conductive film (1st layer is an ITO layer) which has the structure similar to the transparent conductive film disclosed by patent document 1 was manufactured. Specifically, an ITO thin film layer (transparent high refractive index layer refractive index: 2.1) having a thickness of 17 nm was formed on one side of the double-sided hard coat film produced in the same manner as in Example 1 by sputtering deposition using ITO as a raw material.

Next, a 40 nm-thick SiO ₂ thin film layer (transparent low refractive index layer refractive index: 1.5) was formed in the same manner as in Example 2, and then an ITO thin film layer (transparent conductive layer) having a thickness of 13 nm was obtained in the same manner as in Example 1. To form a transparent conductive film of Comparative Example 1.

[ Comparative example  2] Transparent conductive film (transparent film base / SiOx layer/ SiO ₂ layer( Sputtering ) / ITO Manufacture of layers)

Instead of the CeO ₂ layer of Example 2, a 25 nm thick Si0x thin film layer (transparent high refractive index layer refractive index: 1.75) was formed by sputtering deposition using Si as a raw material, argon gas as a process gas, and oxygen gas as a reaction gas. A transparent conductive film of Comparative Example 2 was obtained in the same manner as in Example 2 except for the above.

[ Comparative example  3] Transparent conductive film (transparent film base / ZnS layer/ SiO ₂ layer( Sputtering ) / ITO Manufacture of layers)

A ZnS thin film layer (transparent high refractive index layer refractive index: 2.1) having a thickness of 36 nm was formed by vacuum deposition using ZnS as a raw material instead of the CeO ₂ layer of Example 2, and compared in the same manner as in Example 2. The transparent conductive film of Example 3 was obtained.

[Measurement of Physical Properties]

The surface resistivity, total light transmittance, and b * value of the transparent conductive films obtained in Examples 1 and 2 and Comparative Examples 1-3 were measured. Surface resistivity is described by Mitsubisi Chemical Corporation. Products were measured using Loresta-GP MCP-T600, and the total light transmittance was measured using NIPPON DENSHOKU INDUSTRIES CO., LTD. Product Haze Meter Measured using NDH 2000, b * value is DENSHOKU INDUSTRIES CO., LTD. It was measured using the product SpeCtre Color Meter SQ2000.

Moreover, in order to investigate whether the adhesiveness between each layer formed in the transparent conductive film has a practical problem, the tape adhesiveness was investigated by the following method. First, after the cellophane tape is brought into close contact with the transparent conductive layer (ITO layer), the cellophane tape is peeled and confirmed, and no layer of transparent high refractive index layer, transparent low refractive index layer or transparent conductive layer is peeled off from the transparent conductive film. The case evaluated the case where any one of the transparent high refractive index layer, the transparent low refractive index layer, and the transparent conductive layer peeled from (circle) and a transparent conductive film.

Moreover, when the transparent conductive laminated body and the touchscreen were manufactured using the transparent conductive film obtained in Examples 1 and 2 and Comparative Examples 1-3, the b * value of the part which overlaps with an electrode part, and the whole whole In order to grasp | ascertain the value of a light transmittance, the laminated body which overlaps the whole surface of an electrode part (that is, laminated | stacked two transparent conductive films which do not form a patterned electrode part), and the panel which has the said laminated body are manufactured. The b * value and the total light transmittance were measured.

First, the laminated body was manufactured by sticking two transparent conductive films with the transparent adhesive layer with respect to each of the transparent conductive films obtained in Examples 1 and 2 and Comparative Examples 1-3. The transparent pressure-sensitive adhesive layer is formed by transferring to one transparent conductive film using a high-transparent pressure-sensitive adhesive transfer tape (Sumitomo 3M Limited. Part No. 8146-4) having a uniform acrylic transparent pressure-sensitive adhesive layer formed between two plastic sheets. did. Moreover, this laminated body is adhere | attached so that the nonelectroconductive process surface (surface of the transparent film base side) of the upper transparent conductive film may face, and the electroconductive process surface (surface of the ITO layer side) of the lower transparent conductive film.

About the laminated body which consists of two transparent conductive films obtained in this way, the total light transmittance and b * value were measured similarly to the above.

Moreover, the panel which has a structure which laminated | stacked the said laminated body on the colorless transparent plate-shaped glass of thickness 2mm was formed. Glass and the said laminated body were adhere | attached using the said acrylic transparent adhesive layer. About the panel which consists of the said laminated body and glass obtained in this way, total light transmittance and b * value were measured similarly to the above. Table 1 shows the measurement results.

The laminated body and the panel are transparent conductive laminates shown in B of FIG. 2 except that the patterned electrode portions formed of the transparent conductive layer are not formed (the transparent conductive layer is formed on the entire surface). It has the same structure as the touch panel shown in FIG.

As can be seen from Table 1, the b * values of the transparent conductive films of Examples 1 and 2 and Comparative Examples 1 to 3 were +2.5 or less, respectively.

However, when two sheets were laminated | stacked and the laminated body was comprised, b * value exceeded +2.5 in the transparent conductive films of Comparative Example 1 and Comparative Example 2. Although the transparent conductive film of the comparative example 3 was able to achieve the b * value of +2.5 or less, tape adhesiveness was bad and it could not be used practically.

Moreover, when the panel which laminated two transparent conductive films on the glass was comprised, the b * value of the panel using the transparent conductive film of Comparative Examples 1-3 exceeded +2.5 significantly, and it showed strong yellow taste.

On the other hand, even when the transparent conductive film of this invention of Example 1 and Example 2 was laminated | stacked two sheets and the laminated body was comprised, even if it laminated | stacked two transparent conductive films on glass and comprised a panel, a b * value It was possible to maintain +2.5 or less, thereby achieving desired colorless transparency.

In the case where the transparent conductive film is in the form of a touch panel, it is preferable that the total light transmittance of 85% or more can be achieved. However, all the panels using the transparent conductive films of Examples 1 and 2 satisfy this criterion. I was. In contrast, the total light transmittance of the panel using the transparent conductive film of Comparative Example 3 did not reach 85%.

In addition, the second layer as compared to the transparent conductive film of the second embodiment formed as in Example 1, the sputtering deposition to form a SiO ₂ layer is a (transparent low refractive index layer) by the CVD method, as shown in Table 1, transparent conductive In the case of a film or a laminated body, the b * value was smaller in Example 2, but in the case of a panel, the reversal phenomenon that b * value was smaller in Example 1 was observed. In addition, the total light transmittance of Example 1 was higher than Example 2 in either of the transparent conductive film laminate and the panel. Several additional tests were conducted on this, and the SiO ₂ layer formed by the CVD method was compared with the SiO ₂ layer formed by the sputtering deposition method. However, in the same manner as in the above example, the SiO ₂ layer was formed by the CVD method. When the panel was formed, the total light transmittance was high and the b * value was low. These results it was found that from, Si0 ₂ layer that the transparent conductive film side of a (transparent low refractive index layer) formed by the CVD method is suitable for a touch panel of the electrostatic capacitance method.

Considering the cause of the difference in the method of forming the Si0 ₂ layer affecting the total light transmittance and the b * value, forming the SiO ₂ layer by the CVD method rather than the sputter deposition method, the surface of the SiO ₂ layer side of the CeO ₂ layer is oxidized. As a result, the degree of oxidation is increased, and as a result, the inclination of the degree of oxidation occurs in the CeO ₂ oxide layer (the oxidation degree of the CeO ₂ layer is higher on the SiO ₂ layer side than on the transparent film base side). It is considered that it contributes to the improvement of light transmittance and b * value.

[By etching Pattern  Formation of Electrode Part]

About the transparent conductive films manufactured in Example 1 and Comparative Example 1, the patterned electrode part electrically connected to the X or Y direction was formed by the etching method.

[ Example  3]

First, a resist material (kansai Paint Co., Ltd. AresSPR) was patterned on the transparent conductive film (transparent film substrate / CeO ₂ layer / SiO ₂ layer (CVD) / ITO layer) of the present invention prepared in Example 1. It was applied to the shape of the electrode portion of the phase, wet etching treatment was performed at 40 ° C. for 70 seconds using an aqueous 2% hydrochloric acid solution as an etching solution, and only the ITO layer was removed for the portion where the resist material was not applied, and the CeO ₂ layer / SiO ₂ layer was removed. Was left and the CeO ₂ layer / SiO ₂ layer / ITO layer remained on the portion to which the resist material was applied. After that, by removing the resist material with a 2% aqueous sodium hydroxide solution, a CeO ₂ layer / SiO ₂ layer is formed on the entire surface on a transparent film substrate, and a pattern made of an ITO layer electrically connected to the X direction thereon. The transparent conductive film of this invention in which the upper electrode part was formed was manufactured.

The portions other than the patterned electrode portions are non-electrode portions composed of CeO ₂ layers / Si0 ₂ layers.

In the transparent conductive film of Example 1, since the CeO ₂ layer and the SiO ₂ layer are insulated together, only the ITO layer, which is the third layer (the outermost layer), is removed by etching, so that the transparent conductive film having a patterned electrode part having desired characteristics is formed. Film was obtained.

Moreover, similarly to the above, the transparent conductive film of this invention in which the pattern-shaped electrode part electrically connected to the Y direction was also manufactured.

[ Comparative example  4]

The transparent conductive film (transparent film base material / ITO layer / SiO ₂ layer / ITO layer) manufactured by the comparative example 1 was used instead of the transparent conductive film of this invention manufactured in Example 1, and is the same as Example 3 make it to prepare a comparison of the electrical layers formed of ITO / SiO ₂ layer / additional electrode on the pattern comprising the ITO layer connected to the X direction, for example, a transparent conductive film 4.

The portions other than the patterned electrode portions are non-electrode portions in which neither the ITO layer / SiO ₂ layer / ITO layer remains (see FIG. 5C).

Moreover, similarly to the above, the transparent conductive film of the comparative example 4 which provided the pattern-shaped electrode part electrically connected to the Y direction was also manufactured.

Moreover, when etching the transparent conductive film manufactured by the comparative example 1, when only the ITO layer which is 3rd layer (outermost layer) was etched and removed, the problem of passing electricity through the 1st layer ITO layer generate | occur | produced (FIG. 5) See arrows in partial enlarged view of B). For this reason, in order to obtain the transparent conductive film with the patterned electrode part which has a desired characteristic, it was necessary to etch and remove all the layers from 1st layer to 3rd layer. However, since the SiO ₂ layer of the _second layer is difficult to remove by etching, it is necessary to use a special etching method such as laser etching in order to remove the first layer, compared with the case where only the third layer is removed by etching. It required more cost and time.

From the above results, it has been demonstrated that the transparent conductive film of the present invention has the advantage that the formation of the patterned electrode portion by etching can be performed in a short time and at low cost.

[Transparent Challenge Of the laminate  Produce]

[ Example  4]

The transparent adhesive film of the present invention in which the patterned electrode parts electrically connected to the X direction prepared in Example 3 and the transparent conductive film of the present invention in which the patterned electrode parts electrically connected to the Y direction were formed. The transparent conductive laminated body of this invention was manufactured by sticking with the transparent adhesive layer which was transferred and formed using the tape (refer FIG. 2). Although lamination | stacking did not overlap as much as possible mutually between the electrode parts formed in each transparent conductive film, the part which overlapped slightly between electrode parts generate | occur | produced in the structure of a transparent conductive laminated body. In addition, as shown in FIG. 2B, this transparent conductive laminated body has a non-conductive process surface (surface on the transparent film base material 1 side) of the upper transparent conductive film, and the conductive process surface (ITO) of the lower transparent conductive film. It adhere | attaches so that the surface of the layer 4 side) may face.

[ Comparative example  5]

The comparative example was carried out similarly to Example 4 except having used the transparent conductive film with a patterned electrode part manufactured by the comparative example 4 instead of the transparent conductive film of the present invention with the patterned electrode part manufactured in Example 3. 5 transparent conductive laminated bodies were manufactured.

When the transparent conductive laminate of the present invention prepared in Example 4 and the transparent conductive laminate produced in Comparative Example 5 were visually compared, the transparent conductive laminate prepared in Comparative Example 5 had a portion where the electrode portions overlap each other. It was clearly confirmed that it had a yellow taste.

On the other hand, in the transparent conductive laminate of the present invention prepared in Example 4, the yellow taste of the portion where the electrode portions overlap with each other is almost unnoticeable to the naked eye, and its presence was not known at all.

[Capacitance method Touch panel  Produce]

[ Example  5]

The colorless transparent plate-shaped glass having a thickness of 2 mm and the transparent conductive layer surface (conductive processing surface) of the transparent conductive laminate of the present invention are transferred using the high-transparent pressure-sensitive adhesive transfer tape, and bonded with the formed transparent adhesive layer, The lead-out wiring and the terminal were connected, the touch panel control driver was connected via the flexible printed wiring, and the capacitive touch panel of the present invention was manufactured. The transparent conductive laminate had the same configuration as the transparent conductive laminate prepared in Example 4 except that the drawing wirings were formed in each transparent conductive film.

The lead-out wiring was formed of Ag or Cu.

In the case of forming the lead-out wiring made of Ag, the same treatment as in Example 3 was carried out, and after the transparent conductive film having a patterned electrode portion made of the ITO layer was produced, it was formed by screen printing using Ag paste.

In the case of forming a drawing wiring made of Cu, a 120 nm thick Cu layer is laminated on the entire surface by sputtering deposition on the ITO layer, and a resist material (kansai Paint Co., Ltd. AresSPR) is formed thereon. By using a 5% copper chloride aqueous solution as the etching solution for Cu, and wet etching at 40 ° C. for 60 seconds to remove only the Cu layer where the resist material was not applied, thereby applying the resist material. About the part, the Cu layer remained. After that, the resist material was removed with an aqueous 2% sodium hydroxide solution, thereby producing a drawing wiring made of Cu on the ITO layer. After the lead-out wiring was formed, the same treatment as in Example 3 was performed to produce a transparent conductive film having a patterned electrode portion formed of an ITO layer.

[ Comparative example  6]

Instead of using the transparent conductive laminate of the present invention, the transparent conductive laminate of Comparative Example (except that the above-mentioned outgoing wiring is formed, has the same configuration as the transparent conductive laminate manufactured in Comparative Example 5). In the same manner as in Example 5, the capacitive touch panel of Comparative Example 6 was manufactured.

The capacitive touch panel of the present invention prepared in Example 5 and the capacitive touch panel manufactured in Comparative Example 6 were visually compared. It was clearly confirmed that the parts where the parts overlap with each other have a yellow taste.

On the other hand, in the capacitive touch panel of the present invention manufactured in Example 5, the yellow taste of the portion where the electrode portions overlap each other is hardly felt by the naked eye, and its presence was not known at all.

[Transparent film base / CeO ₂ Review of Adhesion of Layers]

In the case of manufacturing a capacitive touch panel, when the lead-out wiring is made of Ag, interlayer peeling (transparent film base material / CeO ₂ layer / transparent low refractive index layer / transparent conductive layer) which is a practical problem for the transparent conductive film Although no peeling occurred between one was observed, a tendency of peeling easily occurred between the transparent film base material and the CeO ₂ layer was observed when the lead-out wiring was made of Cu. This is because the lead-out wiring made of Cu has higher adhesiveness with the transparent adhesive than the lead-out wiring made of Ag, so that the surface of the transparent conductive film is firmly adhered to another member (star transparent conductive film or glass). result, to the separation between the adhesiveness (cohesiveness) a lower transparent film base material and the CeO ₂ layer generated from the transparent conductive film is considered to be easier.

In order to improve the adhesion between the transparent film substrate and the CeO ₂ layer, first, the surface of the transparent film substrate was modified (introduced with hydroxyl groups) by corona discharge, ion beam irradiation, and plasma treatment, but which surface processing method was used. If also, compared with a case has not been subjected to surface treatment, the result was that the adhesion of the transparent film base material and the CeO ₂ layer decreases.

Since the adhesion between the transparent film substrate and the CeO ₂ layer was rather deteriorated due to the introduction of hydroxyl groups, and the tendency to improve the adhesion was observed when the transparent conductive film was heat treated (140 ° C. for 10 minutes). The adhesiveness of the CeO ₂ layer is considered to be lowered by moisture.

Next, a transparent film was examined for the formation of the anchor coating layer on the substrate, and improving the adhesion between the transparent film substrate and the CeO ₂ layer. The results are shown in Table 2.

The transparent film base material used in Example 6-1 and Example 6-2 forms the transparent hard coat layer of thickness 2micrometer which consists of acrylic resin by the reverse coating method on both surfaces of the 125-micrometer-thick polyethylene terephthalate film. After that, a polyester anchor coating layer having a thickness of 20 nm was formed only on the transparent film base material of Example 6-2 (only one side).

The transparent film base material used in Example 6-3 and Example 6-4 forms the transparent hard coat layer of 2 micrometers in thickness which consists of a urethane type resin by the reverse coating method on both surfaces of the 125-micrometer-thick polyethylene terephthalate film. Thereafter, only the transparent film base material of Example 6-4 was formed with a polyester anchor coating layer having a thickness of 20 nm by the gravure method (only one side).

In addition, the polyester anchor coating layer uses a VM anchor P331S (including polyester polyol and nitrocellulose in a solvent in a weight ratio of 1: 1) by TOYO INK CO., LTD. , Inc. target D-140N (including IPDI-based polyisocyanate prepolymers (adducts of IPDI and TMP) in the solvent), and mixed so that the solid content ratio of the main material and the curing agent is a weight ratio of 1: 1.33, and the mixture It formed by hardening.

About the transparent film base materials of Examples 6-1 to 6-4, the Ce0 ₂ thin film layer, the SiO ₂ thin film layer, and the ITO thin film layer were formed in the same manner as in Example 1 to form the transparent conductive film of the present invention.

Then, about each transparent film, visual evaluation was performed visually, and what was not usable practically by generation | occurrence | production of whitening and a crack was made into x and others.

Moreover, surface resistivity, tape adhesiveness, total light transmittance, and b * value were measured about each transparent film by the method similar to the 1st paragraph of [Measurement of physical properties].

Moreover, the laminated body which consists of two transparent conductive films, and the panel which consists of the said laminated body and glass was manufactured by the method similar to the 2nd and 3rd paragraph of [measurement of a physical property], and the total light transmittance and b * value were measured. .

Moreover, in order to examine the degree of the interlayer peeling in a transparent conductive film at the time of forming the drawout wiring which consists of Cu, a 120-nm-thick Cu layer is laminated | stacked on the surface by the sputter deposition method to the surface of the ITO layer side of each transparent conductive film. And the adhesiveness (adhesiveness) was evaluated by the crosscut method based on JISK5600-5-6 (ISO2409). In addition, in JIS K5600-5-6, the test was conducted at 25 cells, but in this test, in order to examine the adhesion in more detail, the test was conducted at 100 cells, and the Cu layer, the ITO layer, the SiO ₂ layer, and the CeO ₂ layer were (Circle) and 60 or more evaluated (circle) and 30 or more of (circle) and 60 or more of 90 or more of 100 parts which did not peel, and evaluated less than 30 as x. Evaluation ○ The above is a level which is satisfactory practically.

The results are shown in Table 2.

As shown in Table 2, in the case of forming the polyester anchor coating layer (Examples 6-2 and 6-4), compared with the case where no anchor coating layer was formed (Examples 6-1 and 6-3), Crosscut adhesiveness improved. Moreover, total light transmittance became 85% or more and b * value became +2.5 or less for all the transparent conductive films, laminated bodies, and panels.

On the other hand, when the anchor coating layer which consists of epoxy resins was formed, compared with the case where an anchor coating layer was not formed, not only the tendency which total light transmittance and b * value worsened was observed, but also tape adhesiveness and cross cut adhesiveness were observed. A tendency to deteriorate was also observed.

(Industrial availability)

Since the transparent conductive film of the present invention is hardly yellowish even when two sheets are overlapped, even when two transparent conductive films are stacked and used like a capacitive touch panel, the display screen is clearly displayed. We can admit and are very useful.

Moreover, since the formation of the patterned electrode portion by etching is easy, the patterned electrode portion can be formed in a low cost and in a short time.

1, 1 ': transparent film substrate
2: cerium oxide layer
2 ': transparent high refractive index layer containing a conductive material
3, 3 ': transparent low refractive index layer
4, 4 ': transparent conductive layer
4P and 4 ': pattern-shaped electrode part which consists of P transparent conductive layers
4Px: pattern electrode part electrically connected to the X direction which consists of a transparent conductive layer
4Py: pattern-shaped electrode part electrically connected to the Y direction which consists of a transparent conductive layer
5, 5 ': transparent conductive film
6: transparent adhesive layer
7: glass
8: withdrawal wiring
9: clear plastic film
10: hard coat layer
11: polyester anchor coating layer

Claims (10)

A transparent conductive film, wherein a cerium oxide layer, a transparent low refractive index layer having a refractive index of 1.4 or more and less than 1.7 and a transparent conductive layer are sequentially formed on one side of the transparent film substrate. The transparent conductive film of claim 1, wherein the transparent low refractive index layer is a thin film layer made of silicon oxide. The transparent conductive film according to claim 1 or 2, wherein a polyester anchor coating layer is present between the transparent film substrate and the cerium oxide layer. The transparent conductive film according to claim 2 or 3, wherein the thin film layer made of the silicon oxide is formed by chemical vapor deposition (CVD). The transparent conductive film as described in any one of Claims 1-4 whose said transparent conductive layer is a thin film layer which consists of ITO. The thickness of the said cerium oxide layer is 5-200 nm, the thickness of the said transparent low refractive index layer is 5-20 Onm, and the thickness of the said transparent conductive layer is 10-500 nm. Transparent conductive film. The transparent conductive film according to any one of claims 1 to 6, wherein the lead portion and / or the patterned electrode portion are formed. The transparent conductive laminated body formed by laminating | stacking two transparent conductive films as described in any one of Claims 1-6 in which the lead-out wiring and a pattern-shaped electrode part are formed, and sticking with a transparent adhesive layer. The touch panel provided with the transparent conductive film in any one of Claims 1-7. The capacitive touch panel provided with the transparent conductive laminated body of Claim 8.

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