JP2017185671A - Laminate film having substrate with cured layer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminate film that is less likely to cause cracks in an end portion in a TD direction (width direction) while the film is coated with a cured layer.SOLUTION: The laminate film is to be suitably used generally as a substrate for an electrode substrate film of a touch panel, and the laminate film comprises: a resin film 101 made of a super-birefringence resin film in which at least one surface of the film is coated with a cured layer, preferably consisting of an antiglare layer, and a tensile strength in the MD direction is preferably 100 MPa or less; and a multilayer film 102 which is formed on at least a surface on the cured layer coating side of the resin film 101 and which comprises, for example, a metal absorption layer 103 as a first layer, a metal layer 104 as a second layer and a second metal absorption layer 105 as a third layer. Both ends in the TD direction of the resin film 101, preferably in a width range of 1 mm or more and 10 mm or less, are free of the cured layer coating.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a laminate film in which a laminate film is formed on at least one surface of a resin substrate, and particularly to a laminate film in which a laminate film is formed on a resin substrate having a cured layer having an antiglare function.

  In recent years, a technique for installing a “touch panel” on the surface of a flat panel display (FPD) included in electronic devices such as mobile phones, portable electronic document devices, vending machines, car navigation systems, etc. has begun to spread. The “touch panel” can be roughly classified into a resistance type and a capacitance type. The “resistance type” touch panel has a transparent substrate made of a resin film and an X coordinate (or Y coordinate) provided on the substrate. ) A main part is composed of a detection electrode sheet, a Y-coordinate (or X-coordinate) detection electrode sheet, and an insulator spacer provided between these sheets.

  These X-coordinate detection electrode sheet and Y-coordinate detection electrode sheet are usually separated by an insulator spacer, but when pressed with a pen or the like, the two coordinate detection electrode sheets are in electrical contact with each other at that portion. As a result, the position (X coordinate, Y coordinate) touched by the pen can be detected, and if the pen is moved, the coordinates are recognized each time, and finally a character can be input. ing.

  On the other hand, the “capacitance type” touch panel has an X-coordinate (or Y-coordinate) detection electrode sheet and a Y-coordinate (or X-coordinate) detection electrode sheet laminated on an insulating sheet, and further glass on It has a structure in which an insulator such as is arranged. When a finger is brought close to an insulator such as glass, the capacitance of the X coordinate detection electrode and the Y coordinate detection electrode in the vicinity thereof changes, so that the position can be detected.

  As a conductive material for an electrode having a predetermined circuit pattern in the electrode sheet (also referred to as an electrode substrate film), a transparent conductive material such as ITO (indium oxide-tin oxide) as disclosed in Patent Document 1 has been conventionally used. Membranes are widely used. In addition, with an increase in the size of a touch panel, a metal film having a mesh structure made of a thin metal wire as disclosed in Patent Document 2, Patent Document 3, and the like has begun to be used.

  When the above transparent conductive film is compared with a thin metal wire (metal film), the transparent conductive film has an advantage that the circuit pattern such as an electrode is hardly visually recognized because of its excellent transparency in the visible wavelength region. Since the electric resistance value is higher than that of (metal film), there is a disadvantage that is not suitable for increasing the size of the touch panel and increasing the response speed. On the other hand, metal thin wires (metal films) are suitable for increasing the size of touch panels and increasing the response speed because of their low electrical resistance, but they have high reflectivity in the visible wavelength region, so they are processed into a fine mesh structure. However, the circuit pattern may be visually recognized under high-intensity illumination, which has the disadvantage of reducing the product value.

  Therefore, in Patent Document 4 and Patent Document 5, a metal oxide is formed between a transparent substrate made of a resin film and a metal film of the metal thin wire in order to make use of the characteristics of the metal thin wire (metal film) having a low electric resistance value. A method of reducing the reflection of metal fine wires (metal film) observed from the transparent substrate side through a metal absorption layer (also referred to as a blackened film) made of is disclosed.

  In the production of an electrode sheet provided with a metal absorption layer made of this metal oxide, it is usually reacted on the surface of a continuously conveyed long resin film from the viewpoint of increasing the efficiency of film formation of the metal oxide. After a metal absorption layer is continuously formed by reactive sputtering using a metal target (metal material) in an inert gas atmosphere, sputtering is performed using a metal target (metal material) such as copper in an inert gas atmosphere. Thus, a metal layer is continuously formed on the metal absorption layer, thereby producing a laminate film that becomes a base material of the electrode substrate film. Then, the laminated film composed of the metal absorption layer and the metal layer is etched with an etching solution such as a cupric chloride aqueous solution or a ferric chloride aqueous solution, so that an electrode is formed on the laminated film (metal absorption layer and metal layer). A circuit pattern such as the above is patterned.

  Therefore, the laminate film as the base material of the electrode substrate film has a characteristic that the metal absorption layer and the metal layer constituting the laminate film are easily etched by an etching solution such as a cupric chloride aqueous solution or a ferric chloride aqueous solution. Therefore, it is required that a circuit pattern such as an electrode patterned by the etching has a characteristic that it is difficult to be seen under high luminance illumination. Note that the metal layer is laminated as necessary by using a wet plating method such as electrolytic plating. Moreover, the said laminated film is also formed into a film on both surfaces by performing the same process on the surface and back surface of a long resin film.

JP 2003-151358 A JP 2011-018194 A JP 2013-0669261 A JP 2014-142462 A JP 2013-225276 A

By the way, in the laminated structure in which the laminated films 2 patterned on both surfaces of the transparent substrate 1 made of a PET film are provided as shown in FIG. 1, the laminated film 2 is counted from the transparent substrate 1 side as the first layer. In the case of comprising the metal absorption layer 3 by the sputtering method of the eye, the metal layer 4 by the sputtering method and the wet plating method of the second layer, and the second metal absorption layer 5 by the sputtering method of the third layer, the transparent substrate 1 The regular reflection R ₂ of the third metal absorption layer 5 on the front side has a lower reflectance than the regular reflection R ₁ of the first metal absorption layer 3 on the back side. This is because the third-layer metal absorption layer 5 is formed on the second-layer metal layer 4 by a wet plating method having a rough surface, so that the reflected light is easily scattered. Thus, even if the first layer and the third metal absorption layer are formed by sputtering using the same material under the same film formation conditions, the first layer metal on the back side to be observed through the transparent substrate. There was a problem that the reflection of the absorption layer was conspicuous.

  In addition, when a PET film is used as the transparent substrate of the electrode substrate film, there is a problem that rainbow unevenness occurs due to its birefringence, or that it becomes dark when used with polarized sunglasses. As a countermeasure against this, in recent years, a super birefringent film has been adopted as a transparent substrate. However, the super birefringent film has a feature that the breaking strength in the MD direction (length direction) due to the manufacturing method is small, and it is easy to tear in the TD direction (width direction).

  Furthermore, in order to suppress the above-mentioned problem that the reflection of the first metal absorption layer on the back surface side is conspicuous, anti-glare coating treatment is applied to the surface of the resin film to increase the diffuse reflection by forming innumerable irregularities on the surface. There are things to do. However, when a super-birefringent film is used for the transparent substrate and antiglare coating treatment is applied to at least one surface thereof, as shown in FIG. 2, cracks C are formed at the end of the super-birefringent film 6 in the TD direction (width direction). May occur easily.

  The present invention has been made in view of the above-described conventional problems, and in a laminate film formed by forming a laminated film on a resin film such as a super birefringent film, an anti-glare coat is formed on one or both surfaces of the resin film. Even if it gives, it aims at providing the laminated body film which a crack is hard to produce in the edge part of the TD direction (width direction).

  In order to achieve the above object, the laminate film of the present invention is composed of a resin film having at least one surface coated with a cured layer, and a laminate film formed on at least the surface of the cured layer coated side of the resin film. The laminated film is characterized in that both ends of the resin film in the TD direction are not covered with the cured layer.

  According to the present invention, it is possible to suppress the problem of breakage and cracks that are likely to occur when the laminated film is conveyed by roll-to-roll.

It is sectional drawing which showed typically the mode of reflection of the reflected light of the conventional laminated structure which has the laminated film by which patterning was carried out on both surfaces of the resin film. It is the top view which showed typically the crack generation state of the conventional super birefringent resin film with which the anti-glare layer was apply | coated. It is sectional drawing which showed the method of measuring the haze value of a to-be-measured object. It is sectional drawing explaining the influence which the size of the filler of an anti-glare layer has on a haze value. It is sectional drawing explaining the mode of the crack generation by the bending of the resin substrate provided with the anti-glare layer. It is a front view of the coating apparatus of the anti-glare layer used suitably when producing the laminated body film of one specific example of this invention. It is sectional drawing which showed typically the mode of reflection of the reflected light of the laminated structure of one specific example of this invention which has the laminated film patterned on both surfaces of the resin film by which the anti-glare process was carried out. It is a front view of the vacuum film-forming apparatus used suitably in the case of preparation of the laminated body film of one specific example of this invention. The laminate film of one specific example of the present invention having a first metal absorption layer and a second metal layer counted from the transparent substrate side on both sides of a transparent substrate made of a resin film coated with an antiglare layer It is typical sectional drawing. It is typical sectional drawing of the laminated body film of the other specific example of this invention which has the metal layer laminated | stacked with the wet film-forming method on the metal layer of FIG. FIG. 11 is a schematic cross-sectional view of a laminate film of still another specific example of the present invention in which a second metal absorption layer is formed as a third layer on the thickened metal layer of FIG. 10. FIG. 12 is a schematic cross-sectional view of an electrode substrate film having metal laminated thin wires obtained by patterning the laminate film of FIG. 11 on both surfaces of a transparent substrate.

  Hereinafter, a specific example of the laminate film according to the present invention will be described in detail. The laminate film of one specific example of the present invention is composed of a transparent substrate made of a resin film having an anti-glare coating treatment on the back surface and a laminate film provided on both surfaces of the transparent substrate, and each laminate film is The first metal absorption layer, the second metal layer, and the third metal absorption layer are counted from the transparent substrate side.

  The material of the resin film is not particularly limited. For example, polyethylene terephthalate (PET), polyether sulfone (PES), polyarylate (PAR), polycarbonate (PC), polyolefin (PO), triacetyl cellulose (TAC), and norbornene It can select from resin materials, such as. When norbornene is selected as the resin material, representative examples include ZEONOR (trade name) manufactured by ZEON Corporation and ARTON (trade name) manufactured by JSR Corporation. In addition, since the electrode substrate film produced from the laminate film according to the present invention is mainly used for “touch panel”, among the above resin materials, those having excellent transparency in the visible wavelength region are desirable. Further, when a super birefringent film having a tensile strength (conforming to JIS K 7127) in the MD direction (length direction) of about 100 MPa or less is used, a remarkable effect is exhibited.

  The laminate film of one specific example of the present invention is a composite having a structure in which the back surface of the resin film is covered with an antiglare layer. Thereby, in the electrode substrate film obtained by patterning processing such as etching on the laminate film, the first layer formed on the back surface of the resin film subjected to the anti-glare treatment is wet. Since the film is formed on the rough surface in the same manner as the third layer formed on the second layer formed by the plating method, when the circuit pattern on the back side is viewed from the front side, the resin film Since the scattering of incident light through the surface increases as in the front surface side, the specular reflection component on the back surface side can be reduced as in the front surface side.

  As described above, the antiglare layer formed as a hard coat layer (cured layer) harder than the resin film on at least one surface of the transparent substrate made of the resin film has a layer thickness appropriately set according to desired optical characteristics. However, in general, the layer thickness is preferably 0.5 μm or more and 30 μm or less, and more preferably equal to or more than 10 μm or less as the particle diameter used. This antiglare layer is composed of resin and fine particles. As the resin, an ultraviolet curable urethane resin or acrylic resin is preferably used. An inorganic sol such as a silica sol having a particle size of 500 nm or less may be added to the antiglare layer, whereby the hardness of the antiglare layer can be controlled.

  The particle diameter of the fine particles contained in the antiglare layer is preferably in the range of 0.5 to 20 μm and within twice the thickness of the resin layer. The fine particles are preferably blended at a ratio of 1 to 50 parts by mass with respect to 100 parts by mass of the resin. The specific particle size of the fine particles and the blending ratio are appropriately determined in consideration of the desired surface roughness Ra and haze value of the antiglare layer. In general, the surface roughness Ra of the antiglare layer is preferably 0.1 μm or more in order to lower the reflectance of the laminated film (metal absorption layer). As will be described later, the haze value is preferably low. However, when the surface roughness Ra of the antiglare layer is set to 0.1 μm or more, the haze value is 2.5% even if the fine particles contained in the antiglare layer are arbitrarily selected. That's it.

  As the above fine particles, inorganic fine particles or organic fine particles can be used. The inorganic fine particles can be selected from silicon oxide fine particles, titanium oxide fine particles, aluminum oxide fine particles, zinc oxide fine particles, tin oxide fine particles, calcium carbonate fine particles, barium sulfate fine particles, talc fine particles, kaolin fine particles, calcium sulfate fine particles, etc. Organic fine particles include polymethyl methacrylate resin powder (PMMA fine particles), silicone resin powder, polystyrene resin powder, polycarbonate resin powder, acrylic styrene resin powder, benzoguanamine resin powder, melamine resin powder, polyolefin resin powder, polyester resin powder, It can be selected from polyamide resin powder, polyimide resin powder, polyfluorinated ethylene resin powder, and the like.

As an evaluation method of the above antiglare treatment, there is a haze measurement method (JISK7136). This method is a haze value that is the ratio of the scattered light transmittance measured without blocking the transmitted light to the total light transmittance measured by blocking the transmitted light of the integrating sphere with the measurement object fixed by the diffuser plate. It is something to evaluate. Specifically, referring to the schematic diagram of the haze measurement method shown in FIG. 3, the test piece s of the PET film (transparent substrate) subjected to the antiglare treatment is fixed to the light incident side of the integrating sphere h and the integrating sphere The other end side opening of h is closed by the diffusion plate i, the light j is made incident, and the light reflected in the integrating sphere h by multiple reflection is measured by a light receiver k provided below the integrating sphere. Measure the “transmittance” T ₀ . Next, the other end side opening of the integrating sphere h is not closed by the diffuser plate i, and the light j is again incident in the same manner, and the light reflected in the integrating sphere h is reflected (however, the light transmitted through the opening). Is not included) and the “scattered light transmittance” T ₁ is measured by the light receiver k. And haze value (%) is calculated | required from the following formula 1.

[Formula 1]
Haze value = (T ₁ / T ₀ ) × 100

  In the laminated film of one specific example of the present invention, the haze value of the antiglare layer provided on one side of the transparent substrate is desirably 10% or less. This is because when the haze value of the antiglare layer exceeds 10%, the image of the flat panel display observed through the touch panel may be clouded to deteriorate visibility (transmittance). In particular, when the laminated film of the laminate film is etched and patterned into an electrode substrate film, an image of the flat panel display is observed through the antiglare layer on the transparent substrate from which the laminated film has been removed by etching. Therefore, the haze value of the antiglare layer provided on the transparent substrate is desirably 10% or less.

  The haze value of the transparent substrate subjected to the antiglare treatment is mainly determined by the particle size (particle size) and density (particle density) of the fine particles 9 included in the antiglare layer 8 on the transparent substrate 7 as shown in FIG. The haze value increases as the particle size of the fine particles 9 increases and the particle density increases. In the case where fine particles 9A having an excessively large particle size are employed as shown in the upper diagram of FIG. 4, when the metal film is formed by patterning the laminated film, the metal mesh is touched (circuit pattern of the mesh structure). It is necessary to be careful since a gap may be generated when the metal mesh is bonded to another film or the like in a subsequent process of manufacturing as a touch panel having a touch panel.

  In addition, the metal mesh is not only used in a planar form, but may be used in a curved form or folded or opened. The coating agent used for the anti-glare layer is generally of a type having a surface hardness (conforming to JIS K5600-5-4 1999) of 2H or higher after curing (in a usable state), as shown in the left side of FIG. When the hardened layer 8 is formed on the transparent substrate 7 with a hard coating agent, it may break during bending.

  Therefore, in order to make it difficult to break as shown in the right side view of FIG. 5, it is preferable to form a soft hardened layer 8 having a pencil hardness of about HB to H on the transparent substrate 7 after curing (in a usable state). In this case, if the scratch hardness (pencil hardness) of the anti-glare layer in accordance with JIS K5600-5-4 1999 satisfies the condition of H or less, “mechanical properties of coating film” defined in JIS K5600-5-1 1999- In “bending resistance (cylindrical mandrel method)”, a mandrel diameter of 2 mmφ or less can be realized.

  The laminate film of one specific example of the present invention exposes the surface of the transparent substrate at both ends in the TD direction of the transparent substrate. That is, the antiglare layer is not covered at both ends in the width direction of the transparent substrate. Thereby, when a laminated body film is conveyed or handled by a roll-to-roll system etc., problems, such as a fracture | rupture and a crack, do not arise easily. Rolls with various diameters are used for roll-to-roll conveyance, but the holding angle (the angle at which the film contacts the outer peripheral surface of the roll) that causes breakage or cracking is 90 ° or more. Some rolls have a diameter of about 70 mm. In this case, the width of the portion of the transparent substrate that is not covered with the antiglare layer at each end in the TD direction is preferably 1 mm or more and 10 mm or less. If this width is less than 1 mm, it becomes difficult to obtain the effect of suppressing breakage and cracking. On the other hand, if the width exceeds 10 mm, the amount of useless transparent substrates increases, which may be disadvantageous in cost.

  The antiglare layer can be formed on the transparent substrate by a general gravure coating method. For example, it can apply | coat with the coating apparatus 30 of the gravure coat system shown in FIG. The apparatus 30 is provided such that a gravure roll 32 having a rotating shaft extending in the horizontal direction is partially immersed in a solution-like antiglare agent A stored in a storage tank 31. The anti-glare agent A having a certain thickness adheres to the outer peripheral surface by rotating at a predetermined rotational speed.

A pair of blades 33 is provided at a position where the outer peripheral surface of the gravure roll 32 comes out of the liquid surface by rotation. The tip portions of the pair of blades 33 are in contact with both end portions of the outer peripheral surface of the gravure roll 32, and the anti-glare agent A adhering to both end portions of the outer peripheral surface is removed so as to escape outward in the axial direction. . Thereafter, the anti-glare agent A can be applied to the surface of the long resin film F ₀ by sandwiching the long resin film F ₀ before coating conveyed by roll-to-roll between the gravure roll 32 and the sub roll 34. At that time, since the anti-glare agent A at both ends of the outer peripheral surface of the gravure roll 32 is removed by the pair of blades 33 as described above, the long resin film F ₀ has anti-glare only in the region excluding both ends. Agent A can be applied.

  The long resin film coated with the antiglare agent can be dried or cured as necessary to obtain a resin film coated with an antiglare layer composed of a cured layer. The resin film coated with the anti-glare layer is subjected to patterning on both surfaces of the transparent substrate 101 subjected to anti-glare treatment as shown in FIG. 7 by performing a sputtering film forming process, a wet plating process, and a patterning process by etching. Thus, a laminated structure provided with the laminated film 102 can be obtained.

The laminated film 102 of this laminated structure includes a metal absorption layer 103 by a first layer sputtering method counted from the transparent substrate 101 side, a metal layer 104 by a second layer sputtering method and a wet plating method, and a third layer. It consists of a second metal absorption layer 105 formed by the sputtering method of the first layer, and the regular reflection R1 of the _first metal absorption layer 103 on the back surface side through the transparent substrate 101 is changed to the second metal of the third layer on the front surface side. The specular reflection R ₂ of the absorption layer 105 can be made substantially equal. Therefore, it becomes possible to make the reflection of the first metal absorption layer on the back surface side observed through the transparent substrate 101 inconspicuous.

  The film formation of the laminated film on the long resin film covered with the antiglare layer can be suitably performed by a roll-to-roll film forming apparatus 10 as shown in FIG. The film forming apparatus 10 shown in FIG. 8 is also called a sputtering web coater, and conveys a long resin film F coated with a curing agent from the unwinding roll 12 to the take-up roll 16 to the winding roll 24 by a roll-to-roll method. A conveying means for carrying out the process, a film forming means for continuously and efficiently carrying out sputtering film formation on the surface when the long resin film F is wound around the outer peripheral surface of the can roll 16, and a vacuum chamber 11 for accommodating these means; Consists mainly of.

More specifically, the vacuum chamber 11 incorporates various devices (not shown) such as a dry pump, a turbo molecular pump, a cryocoil, and the like. After the pressure is reduced to about ^-4 Pa, the pressure can be adjusted to about 0.1 to 10 Pa by introducing a sputtering gas. A known gas such as argon is used as the sputtering gas, and a gas such as oxygen is further added depending on the purpose. The shape and material of the vacuum chamber 11 are not particularly limited as long as they can withstand such a reduced pressure state, and various types can be used. A partition plate 10a is provided in the vacuum chamber in order to isolate the space for sputtering film formation from the space in which the transport roll group is provided.

  In the conveyance path from the unwinding roll 12 to the can roll 16, a free roll 13 that guides the long resin film F, and a tension sensor roll 14 that measures the tension of the long resin film F upstream of the can roll 16. In addition, a motor-driven front feed roll 15 that adjusts the peripheral speed of the can roll 16 so as to bring the long resin film F fed into the can roll 16 into close contact with the outer peripheral surface of the can roll 16 is arranged in this order.

  The can roll 16 has a coolant whose temperature is adjusted outside the vacuum chamber 11 circulated therein, and can be cooled when the long resin film F wound around the outer peripheral surface is subjected to a process with a heat load by a film forming means. It is like that. Similarly to the above, the transport path from the can roll 16 to the take-up roll 24 is a motor driven post-feed roll 21 that adjusts the peripheral speed of the can roll 16 and the long resin film F downstream of the can roll 16. A tension sensor roll 22 for measuring the tension of the ink and a free roll 23 for guiding the long resin film F are arranged in this order.

  In the unwinding roll 12 and the winding roll 24, the tension balance of the long resin film F is maintained by torque control using a powder clutch or the like. The long resin film F unwound from the unwinding roll 12 by the rotation of the motor-driven can roll 16 and the motor-driven front feed roll 15 and the rear feed roll 21 that rotate in conjunction with the rotation of the motor-driven can roll 16 is described above. After being transported along a transport path defined by a group of rolls such as a can roll 16, it is wound up by a winding roll 24.

  Four magnetron sputtering cathodes 17, 18, 19, and 20 are formed as film forming means along the conveyance path of the can roll 16 at a position facing the region where the long resin film F is wound on the outer peripheral surface of the can roll 16. A pair of gas discharge pipes 25a and 25b, 26a and 26b, 27a and 27b, and 28a and 28b that are capable of discharging reactive gas are provided in the vicinity. Note that when the above-described metal absorption layer or metal layer is formed by sputtering using a plate-like target, nodules (growth of foreign matter) may occur on the target. When this becomes a problem, it is preferable to use a cylindrical rotary target that generates no nodules and has high target use efficiency.

  Of the four magnetron sputtering cathodes 17 to 20 described above, for example, a target for forming a metal absorption layer is provided on the target of the first two cathodes 17 to 18 and a target for the metal layer is provided on the remaining two cathodes 19 to 20. By providing, a metal absorption layer and a metal layer made of a metal oxide can be continuously formed on one surface of the long resin film F.

  And when forming a metal absorption layer and a metal layer continuously on the other surface of the long resin film F, the roll of the long resin film F after film formation is removed from the winding roll 24 and wound. A film can be formed in the same manner by attaching to the unwinding roll 12 and rotating the unwinding roll 12 in the direction of the white arrow as shown in FIG. Thereby, the laminated body substrate of the laminated structure with few dispersion | variation in quality which can be used suitably for the base material of electrode substrate films, such as for touch panels, can be produced.

  In general, when a metal oxide target is used as a target for forming a metal absorption layer, the film forming speed is slow and not suitable for mass production. Therefore, a Ni-based metal target (metal material) capable of high-speed film formation is used. A reactive film-forming method such as reactive sputtering introduced while controlling a reactive gas containing oxygen is performed. In addition, since the metal absorption layer becomes transparent when the oxidation of the metal oxide constituting the metal absorption layer formed by the reactive film formation method proceeds excessively, the oxidation level is suppressed to such a level that it becomes a blackened film visually. Is desirable. When the metal absorption layer is formed by the reactive film formation method, each metal element forms a non-stoichiometric compound with oxygen atoms, and the non-stoichiometric oxide is visually black.

  As a method of controlling the reactive gas, (1) a method of releasing a reactive gas at a constant flow rate, (2) a method of releasing a reactive gas so as to keep the pressure in the vacuum chamber constant, ( 3) Method of releasing reactive gas so that the impedance of the sputtering cathode is constant (impedance control), and (4) Method of releasing reactive gas so that the plasma intensity of sputtering is constant (plasma emission control). The following four methods are known. In addition to the sputtering method using the magnetron sputtering cathodes 17 to 20 as shown in FIG. 8, the reactive film formation method includes dry plating methods such as ion beam sputtering, vacuum deposition, ion plating, and CVD.

  With the film forming apparatus 10 described above, for example, a laminated film composed of the metal absorption layer 51 and the metal layer 52 can be formed on both surfaces of the transparent substrate 50 subjected to the antiglare treatment as shown in FIG. The metal absorption layer 51 is made of Cu, Ni, or Ni containing at least one element selected from the group consisting of Ti, Al, V, W, Ta, Si, Cr, Ag, Mo, Cu, and Zn. It is preferable to comprise a non-stoichiometric metal oxide layer obtained by film formation by a reactive film formation method in a reactive gas atmosphere containing oxygen using an added Ni-based alloy. In the case of a Ni-based alloy, a Ni—Cu alloy is preferable.

  On the other hand, the metal layer 52 can be formed in a general inert gas atmosphere, and the constituent material thereof is not particularly limited as long as it is a metal having a low electric resistance value. , Al, V, W, Ta, Si, Cr, Ag-based Cu alloy with one or more elements added, or Ag alone, or Ag with Ti, Al, V, W, Ta, Si, Cr And Ag-based alloys to which one or more elements selected from Cu are added. Among these, Cu alone is desirable from the viewpoint of circuit pattern workability and resistance.

  The film thickness of the metal absorption layer 51 is preferably about 15 to 30 nm. Since the thickness of the metal layer affects the electrical characteristics, it is not determined only by optical requirements, but it is preferable to set the thickness to a level at which transmitted light cannot be measured. On the other hand, the thickness of the metal layer 52 is preferably 50 to 5000 nm, and more preferably 3 μm (3000 nm) or less from the viewpoint of workability for processing the metal layer into a wiring pattern. In addition, when thickening a metal layer, you may form into a film using wet plating methods, such as an electroplating method, on the metal layer 52 by said dry-type plating method. That is, as shown in FIG. 10, after the metal absorption layer 51 and the metal layer 52 are formed on both surfaces of the antiglare transparent substrate 50 by a dry plating method, the metal layer 53 is formed on the metal layer 52 by a wet plating method. May be formed. The metal layer 53 formed by this dry plating method preferably has a film thickness of 15 μm or less.

  A second metal absorption layer may be further formed on the metal layer 53. That is, as shown in FIG. 11, after forming the metal absorption layer 51 having a film thickness of, for example, 15 to 30 nm and the metal layer 52 having a film thickness of, for example, 50 to 1000 nm on both surfaces of the transparent substrate 50 that has been subjected to the antiglare treatment. Alternatively, the metal layer 53 may be formed by a wet plating method, and the second metal absorption layer 54 having a film thickness of, for example, 15 to 30 nm may be formed on the metal layer 53 by a dry plating method. This second metal absorption layer is selected from Cu simple substance, Ni simple substance, or Ni, Ti, Al, V, W, Ta, Si, Cr, Ag, Mo, Cu, Zn similarly to the metal absorption layer 51. It is obtained by forming a film by a reactive film formation method in a reactive gas atmosphere containing oxygen using a metal material made of a Ni-based alloy to which elements of more than one species are added.

  By forming a metal absorption layer on both sides of the metal layer thickened by the dry plating method and the wet plating method in this way, when the electrode substrate film produced using this laminate substrate is incorporated into the touch panel, it is made of metal. The circuit pattern having a mesh structure composed of the laminated thin wires can be made difficult to see by reflection. Even when an electrode substrate film is produced using a laminate substrate obtained by forming a metal absorption layer and a metal layer only on one side of a transparent substrate made of a long resin film, it is difficult to see a circuit pattern from the transparent substrate. can do. Further, the optical constant (refractive index, extinction coefficient) at each wavelength of the metal absorption layer is greatly influenced by the degree of reaction, that is, the degree of oxidation, and is not determined only by a metal material made of a Ni-based alloy. In the case of a Ni—Cu alloy, depending on the mixing ratio of Ni and Cu, a metal absorption layer that is visually recognized as a black film even if a method that does not use a reactive film formation method (that is, a film formation method that does not use a reactive gas). May be deposited.

  An electrode substrate film can be obtained by patterning the laminated film of the laminate film produced above to form a metal laminated thin wire having a line width of, for example, 20 μm or less. Specifically, an electrode substrate film as shown in FIG. 12 can be obtained by patterning the laminated film of the laminate film shown in FIG. 11 by an etching process or the like. The electrode substrate film shown in FIG. 12 has a circuit pattern having a mesh structure made of, for example, metal multi-layer thin wires having a line width of 20 μm or less provided on both surfaces of the anti-glare transparent substrate 50. The thin line is composed of a first metal absorption layer 51a, a second metal layer 52a, 53a, and a third metal absorption layer 54a as counted from the transparent substrate 50 side.

  Thus, it can use for a touch panel by making the electrode (wiring) pattern of an electrode substrate film into stripe form or a grid | lattice form, and the metal lamination | stacking thin wire in this case is maintaining the laminated structure of the said laminated body film. Therefore, even under high-luminance illumination, circuit patterns such as electrodes provided on the transparent substrate are extremely difficult to visually recognize. That is, when reactive sputtering film formation is performed in a reactive gas atmosphere obtained by adding oxygen to argon, a black film is obtained as a metal absorption layer, so that it becomes possible to suppress the reflectance of light when irradiated, Therefore, a circuit pattern such as an electrode obtained by etching the metal absorption layer is hardly visible under high-intensity illumination. Furthermore, as described above, since the anti-glare layer having a haze value of 10% or less is preferably provided on the transparent substrate made of a resin film, the visibility of the flat display panel is adversely affected when the image of the flat display panel is observed through the electrode substrate film. It becomes difficult to exert.

  A known subtractive method can be used as a method for forming the electrode substrate film by patterning the laminate substrate. In the subtractive method, a photoresist film is formed on the laminate film surface of the laminate substrate, and exposure and development processes are performed so that the photoresist film remains at a position where an electrode pattern is to be formed, and the laminate film exposed from the photoresist film. In this method, the portion is removed by chemical etching to form an electrode pattern. As an etching solution for the above chemical etching, an aqueous solution of ferric chloride or an aqueous solution of cupric chloride can be used.

  As mentioned above, although the laminated body film of one specific example of this invention was demonstrated, the use of a laminated body film is not limited to the electrode substrate film for touch panels, It can use also for a flexible wiring board. When the multilayer substrate is used as a flexible wiring substrate, the multilayer film has a multilayer structure in which each of both surfaces is at least two layers. For example, the first layer is Ni, Ti, Al, V, W, Ta , Si, Cr, Ag, Mo, Cu, and a nickel alloy layer to which one or more elements selected from the group consisting of Zn are added, and the second layer is composed of a metal layer made of a copper layer Is preferred. In addition to the resin film constituting the transparent substrate used in the laminate film for the electric substrate film, a colored film can be used as the long resin film when transparency is not required. For example, a resin film such as a polyimide film can be used.

  First, a super birefringent film (model number: Cosmo Shine SRF film) having a thickness of 50 μm, a width of 600 mm, and a length of 1200 m made by Toyobo was prepared, and both sides thereof were coated with an antiglare layer except for both ends in the width direction. A gravure coating type coating apparatus 30 as shown in FIG. 6 was used for coating. Specifically, an antiglare coating agent A in which a silica diameter filler having a diameter of 1 μm was dispersed in a UV curable acrylic resin so that the gravure roll 32 was partially immersed was stored in the storage tank 31.

Next, the gravure roll 32 is rotated while adjusting the rotation speed so that the anti-glare coating agent A having a film thickness of about 1 μm is applied to the long resin film F _{0 made} of a super birefringent film, and the anti-glare coating is applied to the outer peripheral surface thereof. Agent A was deposited. At the same time, the anti-glare coating agent A adhering to both ends of the outer peripheral surface of the gravure roll 32 is removed with a pair of blades 33, and both ends in the width direction of the long resin film F ₀ are each 3 mm from the edge. The anti-glare coating agent A was not applied in the band region. Then, the long resin film F ₀ conveyed by roll-to-roll is sandwiched between the gravure roll 32 on which the anti-glare coating agent A adheres to the outer peripheral surface and the sub-roll 34 rotating in the opposite direction, thereby anti-glare coating. It was transferred as the agent a to the surface of the long resin film F _0.

After the formation of the antiglare layer is cured by this way a dry anti-glare coating agent A was applied to the long resin film F _0, was also formed antiglare layer on the other surface in the same manner. A laminated film was formed on both sides of the obtained super-birefringent film after coating using a film forming apparatus (sputtering web coater) 10 as shown in FIG. The pencil hardness of the antiglare layer was intermediate between HB and H.

  A stainless steel cylindrical member having an outer diameter of 600 mm and a width of 750 mm was used for the can roll 16 of the film forming apparatus 10, and the outer peripheral surface thereof was subjected to hard chrome plating. The front feed roll 15 and the rear feed roll 21 were each made of a stainless steel cylindrical member having an outer diameter of 150 mm and a width of 750 mm, and the surfaces thereof were also plated with hard chrome. The magnetron sputtering cathodes 17 and 18 were attached with a Ni—Cu target for the metal absorption layer, and the magnetron sputtering cathodes 19 and 20 were attached with a Cu target for the metal layer.

The super birefringent film covered with the above-mentioned cured layer was set on the unwinding roll 12, and its tip was wound around the winding roll 24 through various roll groups. The temperature of the refrigerant circulating in the can roll 16 was controlled at 0 ° C. In this state, the inside of the vacuum chamber 11 was evacuated to 5 Pa by a plurality of dry pumps, and then evacuated to 3 × 10 ⁻³ Pa using a plurality of turbo molecular pumps and a cryocoil. Then, the coated super birefringent film was conveyed at 2 m / min to perform sputtering film formation.

  At the time of sputtering film formation, in the magnetron sputtering cathodes 17 and 18 for forming the metal absorption layer, argon gas is 500 sccm and oxygen gas is 50 sccm from the gas release pipes 25 a and 26 a and b disposed in the vicinity thereof. The power was controlled so that a Ni—Cu oxide layer having a thickness of 30 nm was obtained. On the other hand, in the magnetron sputtering cathodes 19 and 20 for forming a metal layer (copper layer), argon gas is introduced at a flow rate of 500 sccm from the gas discharge pipes 27 a and b and 28 a and b disposed in the vicinity thereof, Power control was performed so that a Cu layer having a thickness of 80 nm was obtained on the Ni—Cu oxide layer.

  After sputtering film formation was completed on one side of the super birefringent film, the atmosphere was introduced into the vacuum chamber 11, and the wound super birefringent film was removed from the take-up roll 24 and set on the unwind roll 12. A sputtering film was also formed on the other surface in the same manner. After the sputtering film formation on both sides is completed, a film is formed on both surfaces by electroplating so that the copper thickness becomes 1 μm, and the film thickness of 30 nm is formed on both surfaces by the same method as described above using the film formation apparatus 10 again. Two metal absorption layers were formed by sputtering.

For comparison, a laminated film was formed on both sides in the same manner as described above except that the pair of blades 33 of the coating apparatus 30 was removed and the entire surface of the super birefringent film F ₀ was covered with the antiglare layer. In this way, a laminated film composed of the first Ni-Cu oxide film, the second Cu film, and the third Ni-Cu oxide film is laminated on both surfaces of the super birefringent film. The laminate films of the examples and comparative examples were prepared. Then, patterning was performed on these both laminated films using a ferric chloride aqueous solution as an etching solution, and electrode substrate films were produced.

  When the electrode substrate films of these examples and comparative examples were visually confirmed, the anti-glare layer was formed on the entire surface of the super-birefringent film, so that impacts such as tension fluctuations were applied. Cracks that seem to have occurred at both ends. On the other hand, in the electrode substrate film of the example, no anti-glare layer was formed on both ends of the super birefringent film, so no crack was found. Thus, it is presumed that the occurrence of cracks was suppressed because the surface hardness was slightly reduced by covering the entire surface without covering the antiglare layer but excluding both ends. In the electrode substrate film of this example, the electrode on the back side through the transparent substrate was hardly visible under high-intensity illumination. Therefore, it turned out that it can utilize suitably as a "touch panel" installed in the surface of FPD (flat panel display).

A Anti-glare coating agent C Crack F ₀ Long resin film before coating of ₀ cured layer F Long resin film coated with cured layer s Test piece h Integrating sphere i Diffuser plate j Light k Receiver T ₀ Total light transmittance T ₁ Scattered light transmission Rate R ₁ Regular reflection of metal absorption layer through transparent substrate R ₂ Regular reflection of second metal absorption layer 1, 101 Transparent substrate 2, 102 Laminated film 3, 103 Metal absorption layer 4, 104 Metal layer 5, 105 Second metal Absorbing layer 6 Super birefringent film 7 Transparent substrate 8 Anti-glare layer 9, 9A Fine particle 10 Film forming apparatus 11 Vacuum chamber 12 Unwinding roll 13, 23 Free roll 14, 22 Tension sensor roll 15 Front feed roll 16 Can roll 17, 18, 19, 20 Magnetron sputtering cathode 21 Rear feed roll 24 Winding roll 25a / b, 26a / b, 27a / b 28a · b Gas release pipe 30 Coating device 31 Storage tank 32 Gravure roll 33 Blade 34 Sub roll 50 Resin film (transparent substrate)
51 Metal absorption layer 52 Metal layer (copper layer) formed by dry film-forming method
53 Metal layer (copper layer) formed by wet film formation method
54 Second metal absorption layer 51a Patterned metal absorption layer 52a Patterned metal layer (copper layer) formed by dry deposition method
53a Metal layer (copper layer) formed by wet film-forming method patterned
54a Patterned second metal absorption layer

Claims (6)

  A laminate film composed of a resin film having at least one surface coated with a cured layer, and a laminated film formed on at least the surface of the resin film on the cured layer coating side, the TD direction of the resin film A laminated film characterized in that the cured layer is not covered at both ends of the film.   The laminate film according to claim 1, wherein the cured layer is harder than the resin film and softer than a pencil hardness H.   The laminate film according to claim 1 or 2, wherein the hardened layer is an antiglare layer.   The width | variety of the part which is not coat | covered with the said hardened layer is 1 mm or more and 10 mm or less, The laminated body film of any one of Claims 1-3 characterized by the above-mentioned.   The laminate film according to any one of claims 1 to 4, wherein the resin film is a super-birefringent resin film having a tensile strength in the MD direction of 100 MPa or less. The laminated film includes a first metal absorption layer, a second metal layer and a third metal absorption layer counted from the resin film side, and the metal absorption layer and the second metal. The absorption layer is made of Ni or Cu, or a metal made of Ni-based alloy to which one or more elements selected from Ti, Al, V, W, Ta, Si, Cr, Ag, Mo, Cu, and Zn are added. The laminate according to any one of claims 1 to 5, wherein the laminate is a non-stoichiometric metal oxide layer formed by a reactive film formation method using a reactive gas containing a material and oxygen. Body film.

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