KR20170028968A - Blackened surface treated copper foil and copper foil with carrier foil - Google Patents

Abstract

There is provided a blackened surface treated copper foil having a treated surface blackened by fine roughening using copper particles. The blackened surface-treated copper foil is a blackened surface-treated copper foil having a square-root-mean-square slope R? Q of a roughness curve measured in accordance with JIS B 0601 (2001) of 25 or less and satisfying JIS Z 8729 (2004) and JIS Z 8722 (2009), wherein the lightness L * of the L * a * b * colorimetric system is 30 or less. According to the present invention, it is possible to increase the film transparency after the copper foil etching when the resin film is applied to a stripe or mesh-like wiring for a touch panel in a state of being laminated to a resin film, It is possible to provide a blackened surface-treated copper foil capable of realizing black.

Description

TECHNICAL FIELD [0001] The present invention relates to a blackened surface-treated copper foil and a copper foil with a carrier foil,

The present invention relates to a blackened surface-treated copper foil and a copper foil with a carrier.

2. Description of the Related Art In recent years, touch panels have been employed in various electronic apparatuses such as mobile phones and portable information terminals. The touch panel is an electronic component that is combined with an input device for detecting a contact position of a fingertip or a pen tip on a display surface of a display panel such as a liquid crystal display device. The convenience is high. There are various types of touch panel, such as a resistance film type and a capacitance type, depending on the difference in structure and detection method.

Particularly, the capacitive touch panel detects the position by capturing a change in capacitance between the fingertip and the conductive film. By taking advantage of the fact that the finger comes close to the surface of the panel to cause electrostatic coupling, It is possible to express or manipulate the cursor before. There are two types of electrostatic capacity type, surface type and projection type. 1, the projection type electrostatic capacitive touch panel 10 has two layers of transparent electrode layers 12 and 12 'patterned in the x-axis direction and the y-axis direction, respectively, with an insulating layer 14 interposed therebetween And detects the touched position from a change in capacitance between the electrodes. Since the touched position can be detected with high precision, it is employed in a portable device such as a smart phone. 1, a laminate of the transparent electrode layer 12 / the insulating layer 14 / the transparent electrode layer 12 'is sandwiched between the glass substrate 16 and the protective cover 18.

In recent years, it has been proposed to use a copper foil in the form of a stripe-shaped or mesh-like copper wiring instead of the ITO (indium tin oxide) transparent electrode which has been widely used in the capacitive touch panel. Such a copper wiring is lower in resistance than the ITO transparent electrode, and therefore, a touch panel having higher sensitivity and excellent operation stability can be realized. For example, Patent Document 1 (Japanese Patent Application Laid-Open No. 2013-206315) discloses a touch panel sensor provided with stripe-shaped or mesh-like copper wirings at each of portions where the film surface and back surface are required to be viewed. In the touch panel sensor of Patent Document 1, the copper wiring is originally made of an oxide film to blacken the surface of the copper wiring on which the copper wiring is to be visually recognized, So that the lowering of the contrast when the touch panel sensor is mounted on the display is suppressed. The formation of the stripe-like or mesh-like copper wiring is performed by patterning by photolithography and etching removal of the copper foil on the laminate obtained by laminating the copper foil on the film. Thereafter, The blackening treatment is performed using the chemical solution.

On the other hand, as a copper foil used for an electromagnetic shielding conductive mesh for a plasma display front panel, a copper foil subjected to blackening or browning treatment is known. For example, Patent Document 2 (WO2007 / 007870) discloses a surface-treated copper foil having a nickel-based blackened surface or a cobalt-based blackened surface on the surface of an untreated copper foil. Patent Document 3 (Japanese Patent Laid-Open No. 2005-187913) discloses a brown surface treated copper foil having a brown surface formed by copper plating performed in multiple steps.

Japanese Patent Application Laid-Open No. 2013-206315 International Publication No. 2007/007870 Japanese Patent Application Laid-Open No. 2005-187913

However, if it is possible to use a surface-treated copper foil that has previously been blackened or browned as described in the reference 2 or the reference document 3 as a wiring material for a touch panel sensor, it is not necessary to perform the blackening treatment separately. On the other hand, since the copper wiring such as a striped image as in Patent Document 1 is formed by removing the copper foil by etching, in order to make the image displayed on the touch panel such as the liquid crystal display device clear, (For example, a resin film such as a PET film) becomes important, and the transparency of the film at the portion where the copper foil is etched (hereinafter referred to as the transparency of the film after the copper foil etching) Because the surface profile such as the surface roughness of the copper foil is transferred to the surface of the film and therefore greatly depends on the surface profile of the copper foil. In view of this, the surface-treated copper foil described in Patent Document 2 is excellent in transparency of the film after the copper foil etching, but since the nickel-based blackening treatment or the cobalt blackening treatment, which is more difficult to dissolve than copper than the copper etching solution, Line irregularity occurs at the time of etching or the copper etching solution becomes dirty and it becomes difficult to control the liquid concentration. In addition, the surface-treated copper foil described in Patent Document 3 does not include a heterogeneous metal which is an etch inhibiting factor on the surface to be subjected to the browning treatment, so that unevenness in line at the time of etching such as the blackening treatment in Patent Document 2 is unlikely to occur, Since the transparency of the film after the copper foil etching is deteriorated by the multi-step baking plating, the backlight is scattered, and the image on the liquid crystal display part is hard to be seen clearly.

The inventors of the present invention have found that by making the copper foil black by fine roughening using copper particles and thereby reducing the unevenness and the inclination of the processed surface, the copper foil can be stuck to the resin film to form stripe or mesh- It is possible to realize transparency of the film after the copper foil etching and to realize a preferable black color sufficient to reduce the visibility of the stripe or mesh wiring.

Therefore, an object of the present invention is to provide a resin film which is capable of enhancing film transparency after copper foil etching when processed into stripe or mesh-like wiring for a touch panel in a state of being laminated to a resin film and also reducing visibility of stripe or mesh- Which is suitable for use as an electrode material for a touch panel, which is capable of realizing a preferable black color sufficient for forming a blackened surface. Another object of the present invention is to provide a copper foil with a carrier foil having such a blackened surface-treated copper foil.

According to one aspect of the present invention, there is provided a blackened surface-treated copper foil having a treated surface blackened by fine-graining using copper particles,

The surface to be treated has a surface roughness R? Q of 25 or less, which is measured in accordance with JIS Z 8729 (2004) and JIS Z 8722 (2009), measured in accordance with JIS B 0601 (2001) And the lightness L * of the L * a * b * color system is 30 or less.

According to another aspect of the present invention, there is provided a carrier foil comprising a carrier foil, a release layer provided on the carrier foil, and a blackened surface-treated copper foil of the present invention provided on the release layer, An attached copper foil is provided.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a diagram showing a general configuration of a projection type capacitive touch panel. Fig.
2A is a view showing an example of a copper wiring for a touch panel;
2B is a view showing another example of a copper wiring for a touch panel;

Blackening  Surface treatment copper

The copper foil of the present invention is a blackened surface-treated copper foil. This blackened surface-treated copper foil has a treated surface blackened by micro-coarsening using copper particles. The roughness curve of the treated surface is characterized by small irregularities due to blackening by micro-coarsening using copper particles, and in particular, the irregularities have a small slope. The surface to be processed having a small inclination of this unevenness is defined by the fact that the root-mean-square slope R? Q of the roughness curve measured in accordance with JIS B 0601 (2001) is 25 or less. When the inclination of the concavities and convexities, that is, the R? Q is small, it is possible to significantly increase the transparency of the film after the copper foil etching in a case where it is applied to a resin film (for example, a PET film) have. As described above, in order to clearly display an image displayed on a touch panel such as a liquid crystal display device, it is important to secure transparency of the film after the copper foil etching. However, by using the blackened surface-treated copper foil of the present invention, Can be realized. This blackened surface-treated copper foil is capable of realizing a preferable black color sufficient to reduce the visibility of the stripe or mesh-like wiring. This characteristic can be obtained by measuring the L value measured in accordance with JIS Z 8729 (2004) and JIS Z 8722 (2009) * a * b * It is stipulated that the lightness L * of the colorimetric system is 30 or less. As described above, although the copper wiring inherently has high reflectance due to specular mirror reflection peculiar to the metal, the display image can be made clear when mounted on a display as a touch panel sensor by making the lightness to the brightness L * as described above . Thus, according to the present invention, in the case where the resin film is processed into stripe or mesh-like wiring for a touch panel in a laminated state, the film transparency after the copper foil etching can be increased and the visibility of the stripe or mesh wiring can be reduced There is provided a blackened surface-treated copper foil capable of realizing a sufficient preferable black color.

Therefore, the blackened surface-treated copper foil of the present invention is preferably used as a wiring material for a touch panel sensor and is a better substitute material having lower resistance than the ITO transparent electrode widely used in conventional touch panel sensors. 2A, when the blackened surface-treated copper foil of the present invention is used as a wiring material for a touch panel sensor, in a configuration in which the copper wiring 22 and the film 24 are laminated, It is preferable to dispose the processing surface 22a on the side of the film 24 facing the blackened processing surface 22a. 2B, copper wirings 22 and 22 'may be laminated on both sides of the film 24, but in this case, at least the upper copper wiring 22' It is preferable to dispose on the blackened treatment surface 22a 'on the side of the wiring 22' with respect to the film 24 and to treat the side where the copper wirings 22 and 22 ' But may be directed to the surfaces 22a and 22a '. In any of the configurations of Figs. 2A and 2B, the copper wiring may have a blackened processing surface on the side opposite to the side to be visually recognized.

The blackened surface-treated copper foil of the present invention has a treated surface blackened by micro-coarsening using copper particles. Thus, the blackened treatment surface of the present invention is composed of copper particles, and therefore has excellent etching properties. That is, the nickel-based blackening treatment or the cobalt blackening treatment, which is more difficult to dissolve than copper than the copper etching solution as disclosed in Patent Document 2, may cause unevenness in etching at the time of etching or contaminate the copper etching solution, It is difficult to control, but such drawbacks are solved. Therefore, it is preferable that the copper particles are made of copper and inevitable impurities. The particle size of the copper particles is not particularly limited. This is because the particle size of the copper particles is reflected in the surface property parameters such as the root-mean-square slope R? Q of the roughness curve, the average height Rc of the roughness curve elements, and the arithmetic mean roughness Ra. Above all, the particle size of the copper particles is preferably 10 nm to 250 nm. The shape of the copper particles is not particularly limited, but from the viewpoint of effectively preventing the powder from falling off, the shape of the copper particles is preferably substantially spherical.

The surface to be treated of the blackened surface-treated copper foil of the present invention has a root-mean-square slope R? Q of the roughness curve of 25 or less. R? Q is a square mean square root of the local slope dZ / dx in the reference length l of the roughness curve measured in accordance with JIS B 0601 (2001)

. RΔq is a parameter obtained by averaging the slope of the irregularities and clearly indicates whether or not the ridges on the treated surface are present. That is, when R? Q is too high, it means that the ridges and irregularities are excessively large, and the transparency of the film after copper foil etching deteriorates. In this respect, when R? Q is 25 or less, the ridges and irregularities on the treated surface become smaller, so that the transparency of the film after the copper foil etching is improved. The preferable R? Q is 3 to 25, more preferably 3 to 10, particularly preferably 3 to 8, and most preferably 4 to 7. With such a range, the transparency of the film after the copper foil etching can be further improved, and the amount of fine roughening can be reduced to some extent to blacken by ridges.

The treated surface of the blackened surface-treated copper foil of the present invention has a lightness L * of the L * a * b * colorimetric system measured according to JIS Z 8729 (2004) and JIS Z 8722 (2009) 20 or less, more preferably 15 or less, further preferably 13 or less. The lower limit value is not particularly limited, but is, for example, 0.5 or more. The lightness L * means that the lower the value, the darker the appearance. The higher the value, the more whiter it means. In this respect, in the above range, visibility of the stripe or mesh-shaped wiring can be more effectively reduced when the resin film is applied to the stripe for the touch panel or the mesh-like wiring. As a result, a display image can be made clear when mounted on a display as a touch panel sensor.

The treated surface of the blackened surface-treated copper foil of the present invention preferably has a Y value of 10 or less, more preferably 5 or less, of the XYZ colorimetric system measured in accordance with JIS Z 8701 (1999) and JIS Z 8722 (2009) . The lower limit value is not particularly limited, but is typically 0.5 or more. The Y value is called a luminous reflectance (luminous reflectance), and is a parameter having both green and reflectance. Particularly, when the Y value is 10 or less, it is preferable that the reflectance is lowered and the phenomenon that the sensor of the display unit reflects and looks white can be effectively avoided or suppressed.

The treated surface of the blackened surface-treated copper foil of the present invention preferably has an a * value of 4 or less in the L * a * b * colorimetric system measured in accordance with JIS Z 8729 (2004) and JIS Z 8722 (2009) Preferably -5 to 3, more preferably -3 to 2. The a * value of the L * a * b * color system means that the higher the value is the hue with a reddish hue, the hue with redness tends to be conspicuous in human eyes. In this regard, in the use of the wiring material for the touch panel sensor, when the a * value is in the range as described above, the redness is not emphasized and the wiring becomes less conspicuous.

The surface to be treated of the blackened surface-treated copper foil of the present invention preferably has an average height Rc of roughness curved elements measured according to JIS B 0601 (2001) of 0.1 to 1.0 m, more preferably 0.1 to 0.8 m, More preferably 0.1 to 0.5 占 퐉, and particularly preferably 0.2 to 0.4 占 퐉. If the thickness is within the above-mentioned range, peeling of the circuit is unlikely to occur, and the linearity of the circuit pattern can be easily realized when the resin film is processed into stripe or mesh-like wiring for the touch panel.

The treated surface of the blackened surface-treated copper foil of the present invention preferably has an arithmetic average roughness Ra measured according to JIS B 0601 (2001) of 0.10 to 0.35 탆, more preferably 0.15 to 0.25 탆, Lt; / RTI > If the thickness is within the above-mentioned range, peeling of the circuit is unlikely to occur, and the linearity of the circuit pattern can be easily realized when the resin film is processed into stripe or mesh-like wiring for the touch panel.

When the blackened surface-treated copper foil of the present invention is produced by bonding a blackened surface-treated copper foil to one side of a polyethylene terephthalate resin (PET) film having a thickness of 100 mu m on the side of the treated surface and then removing the copper foil by etching, It is preferable that the remaining polyethylene terephthalate resin film has a haze value of 60% or less, more preferably 50% or less, more preferably 45% or less, particularly preferably 20% or less, 10% or less. The lower limit value is not particularly limited, but is, for example, 1% or more. Since the haze value means opacity, the low haze value as described above means high transparency. Therefore, when the blackened surface-treated copper foil having such a configuration is processed into stripe or mesh-like wiring for a touch panel by being laminated to a resin film, transparency of the film after copper foil etching can be increased. The haze value was obtained by thermocompression bonding a blackened surface treated copper foil and a PET film (thickness: 100 mu m) to produce a copper clad laminate, etching the surface treated copper foil, removing the remaining PET film, The haze value (Haze: unit%) of the film at 23 占 폚 was measured at three points in accordance with JIS K 7136 (2000) using a haze meter (for example, NDH5000 manufactured by Nippon Denshoku Kogyo K.K.) , And calculating the average value.

The thickness of the blackened surface-treated copper foil of the present invention is not particularly limited, but is preferably 0.1 to 18 탆, more preferably 0.5 to 10 탆, more preferably 0.5 to 7 탆, particularly preferably 0.5 to 5 탆 , And most preferably 0.5 to 3 탆. The blackened surface-treated copper foil of the present invention is not limited to the one obtained by blackening the surface of a conventional copper foil but may be one obtained by blackening the surface of the copper foil of the copper foil with a carrier foil.

Blackening  Manufacturing method of surface-treated copper foil

An example of a preferred method of producing a blackened surface-treated copper foil according to the present invention will be described. However, the blackened surface-treated copper foil according to the present invention is not limited to the method described below, and as long as fine- It may be manufactured by various methods.

(1) Preparation of copper foil

As the copper foil to be used in the production of blackened surface-treated copper foil, both electrolytic copper foil and rolled copper foil can be used. In addition, the copper foil may be a copper foil without coarsening, or it may have been subjected to preliminary harmonization. The thickness of the copper foil is not particularly limited, but is preferably 0.1 to 18 占 퐉, more preferably 0.5 to 10 占 퐉, still more preferably 0.5 to 7 占 퐉, particularly preferably 0.5 to 5 占 퐉, 3 mu m. When the copper foil is prepared in the form of a copper foil with a carrier foil, the copper foil may be formed by a wet film forming method such as an electroless copper plating method and an electrolytic copper plating method, a dry film forming method such as sputtering and chemical vapor deposition, do.

The surface roughness of the copper foil to be finely roughened by the copper particles is preferably not more than 2.0 占 퐉, more preferably not more than 1.2 占 퐉, and even more preferably not more than 0.8 占 퐉. The lower limit value is not particularly limited, but is, for example, 0.1 mu m or more. Within this range, it is possible to reduce the slope of the concave-convex portion defined by the root-mean-square slope R? Q of the roughness curve when the fine particles are coarsely grained by the copper particles, It is possible to significantly increase the transparency of the film after the copper foil etching. The " maximum height difference (Wmax) of the waving needle " means the maximum difference in height difference (Wmax) in the waveform data extracted by filtering the waveform data along the wavy needle from the information about the concavity and convexity of the surface of the sample obtained by using the three- For example, zygo New View 5032 (manufactured by Zygo Co., Ltd.) is used as a measuring instrument, and analysis software is used as the measurement result of Metro Pro Ver. 8.0.2 is used and the low-frequency filter is set to 11 mu m.

(2) Black harmony

And at least one of the surfaces of the copper foil is blackened by fine coarsening using copper particles. This black hatching is performed by electrolysis using a copper electrolytic solution for black coloring. The preferred copper electrolytic solution for black plating is an electrolytic solution having a copper concentration of 10 to 20 g / l, a free sulfuric acid concentration of 30 to 100 g / l, and a chlorine concentration of 20 to 100 ppm. Here, when the copper concentration is less than 10 g / L, the electrodeposition rate of the copper particles is slowed, and the industrially required productivity can not be satisfied, which is not preferable. On the other hand, when the copper concentration exceeds 20 g / L, it is not preferable because it is close to the smoothing plating condition and becomes difficult to harmonize with black due to the current density to be described later. If the concentration of the free sulfuric acid deviates from this concentration range in relation to the copper concentration, it is not preferable because the electric conductivity at the time of electrolysis changes and good black coarsening becomes difficult.

It is preferable to further add an additive to the copper electrolytic solution for black plating to control the fine adjustment. Preferable examples of such additives include a combination of polyethylene glycol and bis (3-sulfopropyl) disulfide, sodium polyacrylate, and the like. For example, polyethylene glycol and bis (3-sulfopropyl) disulfide are preferably added to the copper electrolytic solution for black roasting at a concentration of 10 to 500 ppm, respectively. It is preferable that sodium polyacrylate is added to the copper electrolytic solution for black coloring at a concentration of 10 to 1000 ppm. By adding the additives alone or in combination (appropriately) in this way, it is possible to inhibit the growth of the needle-shaped particles and form spherical fine roughening particles.

The electrolysis using the copper electrolytic solution for blackening harmonization is preferably carried out under the conditions of a current density of 30 to 100 A / dm ² and a time of ^{2 to 10} seconds in the electrolytic solution having a solution temperature of 20 to 40 캜 by polarizing the copper foil to the negative electrode. If the solution temperature is lower than 20 캜, unevenness tends to occur in the shape of the formed coarse particles, which is not preferable. On the other hand, if the solution temperature exceeds 40 캜, the solution characteristics of the black electrolytic solution for conditioning harm tend to change easily, and stable fine adjustment tends to be impossible, which is not preferable. When the current density is less than 30 A / dm < ^{2 >} , sufficient black coarsening can not be achieved and it is not preferable to make the brightness level L * of the black coarse screen 30 or less difficult. On the other hand, when the current density exceeds 100 A / dm ² , the precipitation rate of fine copper particles becomes excessive, and the shape of the copper particles to be formed is not a good sphere, which is not preferable.

(3) Rust treatment

The copper foil after blackening may be subjected to anti-corrosive treatment as desired. The rust-preventive treatment preferably includes a plating treatment using zinc. The plating treatment using zinc may be either a zinc plating treatment or a zinc alloy plating treatment, and the zinc alloy plating treatment is particularly preferably a zinc-nickel alloy treatment. The zinc-nickel alloy treatment may be a plating treatment containing at least Ni and Zn, and may further include other elements such as Sn, Cr, and Co. The ratio of Ni / Zn in the zinc-nickel alloy plating is preferably 1.2 to 10, more preferably 2 to 7, and still more preferably 2.7 to 4 in mass ratio. Further, it is preferable that the rust-preventive treatment further includes a chromate treatment, and it is more preferable that the chromate treatment is performed on the surface of the plating containing zinc after the plating treatment with zinc. This makes it possible to further improve the rustproofing property. A particularly preferable rust-preventive treatment is a combination of a zinc-nickel alloy plating treatment and a subsequent chromate treatment.

(4) Treatment with silane coupling agent

The copper foil may be treated with a silane coupling agent to form a silane coupling agent layer, if desired. As a result, it is possible to improve the moisture resistance, chemical resistance, adhesion with the adhesive, and the like. The silane coupling agent layer can be formed by applying a silane coupling agent with dilution and drying. Examples of the silane coupling agent include epoxy functional silane coupling agents such as 4-glycidylbutyltrimethoxysilane and? -Glycidoxypropyltrimethoxysilane, or? -Aminopropyltriethoxysilane, N-? ( Aminopropyltrimethoxysilane, N-3- (4- (3-aminopropoxy) butoxy) propyl-3-aminopropyltrimethoxysilane, N-phenyl- An amino functional silane coupling agent such as silane coupling agent, an amino functional silane coupling agent such as silane coupling agent, an amino functional silane coupling agent such as silane coupling agent, or a silane coupling agent such as a mercapto functional silane coupling agent such as γ-mercaptopropyltrimethoxysilane or an olefin functional silane coupling agent such as vinyltrimethoxysilane or vinylphenyltrimethoxysilane Or an acryl functional silane coupling agent such as γ-methacryloxypropyltrimethoxysilane, or an imidazole functional silane coupling agent such as imidazole silane, or a triazine functional silane coupling agent such as triazinilane .

Carrier foil  Attached copper foil

The blackened surface-treated copper foil of the present invention can be provided in the form of a copper foil with a carrier foil. Particularly, when a narrower circuit pattern width or a height of a copper wiring is set to 5 mu m or less in order to sharpen a display image when mounted on a display as a touch panel sensor, a thin copper foil is used, It is preferable to use a copper foil with a carrier. In this case, the copper foil with a carrier foil comprises a carrier foil, a release layer provided on the carrier foil, and a blackened surface-treated copper foil of the present invention provided on the release layer with the blackened surface outward. Above all, a known layer structure can be employed for the copper foil with a carrier foil, except that the blackened surface-treated copper foil of the present invention is used.

The carrier foil is a foil for supporting the blackened surface-treated copper foil to improve its handling property. Examples of the carrier foil include an aluminum foil, a copper foil, and a resin film having a metal coating on the surface, and is preferably a copper foil. The copper foil may be either a rolled copper foil or an electrolytic copper foil. The thickness of the carrier foil is typically 200 占 퐉 or less, and preferably 18 占 퐉 to 200 占 퐉.

The release layer is a layer having a function of weakening the peeling strength of the carrier foil to ensure the stability of the strength and suppressing mutual diffusion that may occur between the carrier foil and the copper foil at the time of press molding at a high temperature. The release layer is generally formed on one side of the carrier foil, but it may be formed on both sides. The peeling layer may be either an organic peeling layer or an inorganic peeling layer. Examples of the organic component used in the organic release layer include a nitrogen-containing organic compound, a sulfur-containing organic compound, and a carboxylic acid. Examples of the nitrogen-containing organic compound include a triazole compound and an imidazole compound, and among them, a triazole compound is preferable in view of easy stability of peelability. Examples of triazole compounds include 1,2,3-benzotriazole, carboxybenzotriazole, N ', N'-bis (benzotriazolylmethyl) urea, 1H-1,2,4- -1H-1,2,4-triazole, and the like. Examples of the sulfur-containing organic compound include mercaptobenzothiazole, thiocyanuric acid, 2-benzimidazole thiol and the like. Examples of the carboxylic acid include monocarboxylic acid and dicarboxylic acid. On the other hand, examples of the inorganic component used in the inorganic release layer include Ni, Mo, Co, Cr, Fe, Ti, W, P, Zn and a chromate treatment film. The release layer may be formed by bringing the release layer component-containing solution into contact with at least one surface of the carrier foil and fixing the release layer component to the surface of the carrier foil. The carrier foil may be brought into contact with the solution containing the release layer component by immersion in the release layer component-containing solution, spraying of the solution containing the release layer component, dropping of the solution containing the release layer component, and the like. The peeling layer component may be fixed to the surface of the carrier foil by drying the solution containing the peeling layer component, electrodeposition of the peeling layer component in the solution containing the releasing layer component, and the like. The thickness of the release layer is typically 1 nm to 1 占 퐉, preferably 5 nm to 500 nm.

As the blackened surface-treated copper foil, the aforementioned blackened surface-treated copper foil of the present invention is used. The blackened surface-treated copper foil of the present invention is a copper foil subjected to micro-coarsening (blackening) using copper particles. In the procedure, copper layers are first formed on the surface of the release layer as copper foil and then at least micro- . Details of the fine harmony (blackening) are as described above. It is preferable that the copper foil is formed in the form of an ultra-thin copper foil in order to take advantage of the copper foil with a carrier. The thickness of the ultra-thin copper foil is preferably from 0.1 mu m to 7 mu m, more preferably from 0.5 mu m to 5 mu m, and still more preferably from 0.5 mu m to 3 mu m.

Another functional layer may be provided between the peeling layer and the copper foil. An example of such another functional layer is an auxiliary metal layer. The auxiliary metal layer is preferably made of nickel and / or cobalt. The thickness of the auxiliary metal layer is preferably 0.001 to 3 mu m.

[Example]

The present invention will be described more specifically by the following examples.

Example 1 : Blackened surface treated copper foil

The production and evaluation of the blackened surface treated copper foil were carried out as follows.

(1) Production of electrolytic copper foil

A sulfuric acid copper sulfate solution having the composition shown below was used as the copper electrolytic solution, and a rotating electrode made of titanium having a surface roughness Ra of 0.20 占 퐉 was used as a negative electrode. DSA (dimensionally stable positive electrode)占 폚 and a current density of 55 A / dm ² to obtain an electrolytic copper foil having a thickness of 12 占 퐉. The maximum height difference (Wmax) of the wafers on the deposition face of the electrolytic copper foil was 0.8 mu m and the maximum height difference (Wmax) of the wafers on the electrode surface was 1.5 mu m.

<Composition of Sulfuric Acid Sulfuric Acid Solution>

- Copper concentration: 80g / ℓ

- Free sulfuric acid concentration: 140 g / l

Bis (3-sulfopropyl) disulfide concentration: 30 mg / l

- diallyldimethylammonium chloride Polymer concentration: 50 mg / l

- Chlorine concentration: 40 mg / l

&Lt; Difference in maximum height of waved needle (Wmax)) >

As a measuring instrument, zygo New View 5032 (manufactured by Zygo Corporation) was used, Metro Pro Ver.8.0.2 was used as analysis software, and a low-frequency filter was used under the condition of 11 μm to measure the maximum height difference (Wmax) did. At this time, the surface to be measured of the surface-treated copper foil was adhered and fixed to the sample table, and the visual field of 108 占 퐉 144 占 퐉 was selected from 6 points within a range of 1 cm square of the sample piece. The average value of the maximum height difference (Wmax) of the obtained wormhole was adopted as a representative value.

(2) Black harmony

The copper electrolytic solution for black coloring having the composition shown below was used for the electrode surface and the deposition surface of the above-mentioned electrolytic copper foil and on the precipitation surface side under conditions of a solution temperature of 30 캜, a current density of 50 A / dm ² , And black coarsening was carried out.

&Lt; Composition of copper electrolytic solution for black coloring &

- Copper concentration: 13g / ℓ

- Free sulfuric acid concentration: 70 g / l

- Chlorine concentration: 35 mg / l

- Polyethylene glycol concentration: 100 ppm

Bis (3-sulfopropyl) disulfide concentration: 100 ppm

(3) Rust treatment

Both sides of the electrolytic copper foil after blackening were subjected to anti-corrosive treatment comprising an inorganic anti-corrosive treatment and a chromate treatment. First, as an inorganic anti-corrosive treatment, the fatigue acid bath (浴) the use, potassium pyrophosphate concentration of 80g / ℓ, a zinc concentration of 0.2g / ℓ, the nickel concentration of 2g / ℓ, a liquid temperature of 40 ℃, zinc at a current density of 0.5A / dm ² - Nickel alloy rust prevention treatment was performed. Next, as a chromate treatment, a chromate layer was further formed on the zinc-nickel alloy rust-preventive treatment. The chromate treatment was carried out at a chromic acid concentration of 1 g / l, a pH of 11, a solution temperature of 25 캜, and a current density of 1 A / dm ² .

(4) Treatment with silane coupling agent

The copper foil subjected to the rust-preventive treatment was washed with water and then immediately subjected to a silane coupling agent treatment to adsorb a silane coupling agent on the rust-preventive treatment layer of the black roughed surface. This silane coupling agent treatment was carried out by using pure water as a solvent and using a solution having a 3-aminopropyltrimethoxysilane concentration of 3 g / l and spraying the solution onto a black rough surface by showering and adsorbing the solution. After the adsorption of the silane coupling agent, moisture was finally evaporated by an electric heater to obtain a blackened surface-treated copper foil having a thickness of 12 탆.

(5) Evaluation

The obtained blackened surface-treated copper foil was evaluated for various properties as follows.

&Lt; Surface Property Parameters (R? Q, Rc and Ra)>

The surface property parameters R? Q, Rc and Ra of the surface-treated copper foil were measured according to JIS B 0601 (2001) using a laser microscope (OLS4100, manufactured by Olympus Corporation) as an optical measuring device. This measurement was carried out in the width direction of the copper foil with an evaluation length of 642 탆. Here, the width direction of the copper foil corresponds to the width direction (TD direction) of the rotating cathode in manufacturing the electrolytic copper foil.

<Brightness L *, chromaticity a * and Y value>

The Y value was defined as JIS Z (chromaticity a *) in accordance with JIS Z 8729 (2004) and JIS Z 8722 (2009) using a spectrocolorimeter (SE6000 manufactured by Nihon Denshoku Kogyo K.K.) 8701 (1999) and JIS Z 8722 (2009).

<Haze value (Haze)>

A surface-treated copper foil and a PET film (thickness: 100 mu m) were thermally bonded to produce a copper clad laminate. Thereafter, the surface-treated copper foil was removed by etching, and the remaining PET film was laminated to a film at 23 占 폚 according to JIS K 7136 (2000) using a haze meter (NDH5000, manufactured by Nippon Denshoku Chemical Co., Ltd.) (Haze: unit%) at three points, and the average value thereof was determined.

Example 2

A blackened surface-treated copper foil was produced and evaluated in the same manner as in Example 1, except that the black coarsening was conducted on the electrode surface side of the copper foil.

Example 3

The production and evaluation of a copper foil with a carrier foil having a blackened surface-treated copper foil were carried out as follows.

(1) Production of carrier foil

A sulfuric acid copper sulfate solution having the composition shown below was used as the copper electrolytic solution, and a rotating electrode made of titanium having a surface roughness Ra of 0.20 占 퐉 was used as a negative electrode. DSA (dimensionally stable positive electrode)占 폚 and a current density of 55 A / dm ² to obtain an electrolytic copper foil having a thickness of 12 占 퐉 as a carrier foil.

<Composition of Sulfuric Acid Sulfuric Acid Solution>

- Copper concentration: 80g / ℓ

- Free sulfuric acid concentration: 140 g / l

Bis (3-sulfopropyl) disulfide concentration: 30 mg / l

- diallyldimethylammonium chloride Polymer concentration: 50 mg / l

- Chlorine concentration: 40 mg / l

(2) Organic peeling layer formation

The electrode surface side of the pickling copper foil for carrier was immersed in a CBTA aqueous solution containing CBTA (carboxybenzotriazole) of 1000 ppm by weight, sulfuric acid of 150 g / l and copper of 10 g / l for 30 seconds at a liquid temperature of 30 ° C And the CBTA component was adsorbed on the electrode surface of the carrier foil. Thus, a CBTA layer was formed as an organic release layer on the surface of the glossy surface of the copper foil for a carrier.

(3) Formation of auxiliary metal layer

The copper foil for carriers in which the organic release layer was formed was immersed in a solution containing 20 g / l of nickel and 300 g / l of nickel prepared using nickel sulfate and having a liquid temperature of 45 캜, a pH of 3, and a current density of 5 A / dm ² , Nickel of an amount corresponding to 0.002 占 퐉 in thickness was adhered onto the organic release layer. Thus, a nickel layer was formed as an auxiliary metal layer on the organic peeling layer.

(4) Formation of ultra-thin copper foil

The copper foil for carrier in which the auxiliary metal layer was formed was immersed in an acidic copper sulfate solution and was electrolyzed for 60 seconds under a smooth plating condition of a current density of 8 A / dm ² to form an ultra-thin copper foil having a thickness of 3 탆 on the auxiliary metal layer. The maximum height difference (Wmax) of the wormhole on the precipitation surface of this ultra-thin copper foil was 1.1 mu m.

(5) Black harmony

The electrolytic solution for black plating for black coarse copper having the composition shown below was used for the precipitation surface of the ultra-thin copper foil described above, and electrolytic treatment was carried out under the conditions of a solution temperature of 30 캜 and a current density of 50 A / dm ^{2 for 4} sec.

&Lt; Composition of copper electrolytic solution for black coloring &

- Copper concentration: 13g / ℓ

- Free sulfuric acid concentration: 70 g / l

- Chlorine concentration: 35 mg / l

- Sodium polyacrylate concentration: 400 ppm

(6) Rust treatment

Both sides of the ultra-thin copper foil with a carrier foil after blackening were subjected to anti-rust treatment by an anti-rust treatment and a chromate treatment. First, as an inorganic anti-corrosive treatment, exhaustion of the acid bath used, potassium pyrophosphate concentration of 80g / ℓ, a zinc concentration of 0.2g / ℓ, the nickel concentration of 2g / ℓ, a liquid temperature of 40 ℃, zinc at a current density of 0.5A / dm ² - nickel alloy Anti-rust treatment was carried out. Next, as a chromate treatment, a chromate layer was further formed on the zinc-nickel alloy rust-preventive treatment. The chromate treatment was carried out at a chromic acid concentration of 1 g / l, a pH of 11, a solution temperature of 25 캜, and a current density of 1 A / dm ² .

(7) Treatment with silane coupling agent

The copper foil subjected to the rust-preventive treatment was washed with water and then immediately subjected to a silane coupling agent treatment to adsorb a silane coupling agent on the rust-preventive treatment layer of the black roughed surface. This silane coupling agent treatment was carried out by using pure water as a solvent and using a solution having a 3-aminopropyltrimethoxysilane concentration of 3 g / l and spraying the solution onto a black rough surface by showering and adsorbing the solution. After adsorption of the silane coupling agent, water was finally evaporated by an electric heater to obtain a copper foil with a carrier foil having a blackened surface treated ultra thin copper foil with a thickness of 3 mu m.

(8) Evaluation

The obtained copper foil with a carrier foil having a blackened surface-treated copper foil was evaluated for various properties in the same manner as in Example 1.

Example 4 (comparative)

A brownish surface-treated copper foil was produced and evaluated in the same manner as in Example 1, except that the browning treatment described below was performed on the electrode surface side of the electrolytic copper foil instead of black hiding.

<Browning Treatment>

First, an electrolytic copper foil (prepared in Example 1 (1)) which had not undergone the roughening treatment was immersed in a dilute sulfuric acid solution having a sulfuric acid concentration of 150 g / l and a solution temperature of 30 占 폚 for 30 seconds to purify the surface. The thus-purified electrolytic copper foil was subjected to a browning treatment by performing the following steps (a) to (e) in this order.

(a) Basic plating process

A base plating treatment was performed on the electrode side of the electrolytic copper foil to make the surface of the copper foil brown by using a copper sulfate plating solution under baking plating conditions. This base plating treatment was carried out by electrolysis under a baking plating condition of a current density (Ia) of 10 A / dm ² using a copper sulfate solution having a copper concentration of 18 g / l, a free sulfuric acid concentration of 100 g / l and a liquid temperature of 25 캜. As a result, the baking plating performed in this basic plating step only formed nuclei for forming a certain degree of unevenness on the surface of the copper foil, and was an electrodeposited amount of 300 mg / m &lt; 2 &gt;

(b) Additional plating process

The surface of the base plating-treated copper foil thus treated was subjected to a plating treatment once using a copper sulfate plating solution under baking plating conditions. The additional plating was performed using a copper sulfate solution having the same concentration and liquid temperature as in the above step (a). At this time, the current density Ib used in baking plating is set to 1.5 A / dm ² , which is a current density of 15% of Ia, to prevent current concentration on the nucleus formed on the surface of the copper foil in step (a) So that precipitation was prevented. The electrodeposition amount in this additional plating step was set to an electrodeposited amount of 50 mg / m 2 as a converted thickness.

(c) Coating plating treatment process

The copper plating solution thus baked was subjected to plating plating under a smooth plating condition using a copper plating solution. This coated plating was carried out by electrolysis using a copper sulfate solution having a copper concentration of 65 g / l, a free sulfuric acid concentration of 150 g / l and a liquid temperature of 45 캜 under a smooth plating condition of a current density of 15 A / dm ² . Thus, the surface roughened in the steps (a) and (b) was smoothed. The converted thickness of the smooth plating was 4 g / m 2.

(d) Finishing plating process

A copper plating solution was applied to the surface subjected to the smoothing plating treatment in this manner under the baking plating condition to finish the copper plating surface to finish brown, thereby forming very fine copper grains (copper grains) . Formation of this microscopic equivalent was carried out in the same manner as in Example 1 except that 9-phenylacridine was added and the concentration of copper was 13 g / L, 50 g / L of free sulfuric acid, 150 mg / L of 9-phenylacridine, 28 ppm of chlorine, Copper sulfate solution at an electric current density of ²⁴ A / dm ² . The electrodeposition amount in this finish plating treatment step was set to an electrodeposited amount of 300 mg / m 2 as a converted thickness.

(e) Cleaning and drying process

The copper foil subjected to finish plating in this manner was sufficiently washed with pure water for showering, and the copper foil was allowed to stand for 4 seconds in a drying furnace at an ambient temperature of 150 캜 by an electric heater to evaporate the water, A treated copper foil was obtained. The flushing is not limited to this step, and the flushing solution is not carried into the post-processing during the above-described respective steps.

Example 5 (comparative)

Preparation and evaluation of the surface-treated copper foil were carried out in the same manner as in Example 2 except that no black coarsening was carried out.

result

The evaluation results obtained in Examples 1 to 5 were as shown in Table 1.

[Table 1]

From the results shown in Table 1, in Examples 1 to 3 in which the blackened surface-treated copper foil having R? Q of 25 or less and the lightness L * of the L * a * b * colorimetric system was 30 or less, a low haze value was realized And it is understood that the film transparency after the copper foil etching becomes high. In addition, a preferable black color sufficient for reducing the visibility of stripe or mesh wiring is realized. In Examples 1 to 3, the a * values of the L * a * b * color system were all low, indicating a desirable color tone in which the redness was not emphasized (i.e., wiring becomes less conspicuous). Therefore, the blackened surface-treated copper foil of the present invention is extremely suitable for use as a wiring material for a touch panel sensor.

Claims (11)

A blackened surface-treated copper foil having a treated surface blackened by fine roughening using copper particles,
The surface to be treated has a surface roughness R? Q of 25 or less, which is measured in accordance with JIS Z 8729 (2004) and JIS Z 8722 (2009), measured in accordance with JIS B 0601 (2001) L * a * b * Blackened surface treated copper having a lightness L * of the colorimetric system of 30 or less. The method according to claim 1,
Wherein the treated surface is a blackened surface-treated copper foil having a Y value of XYZ color system measured according to JIS Z 8701 (1999) and JIS Z 8722 (2009) of 10 or less. 3. The method according to claim 1 or 2,
Wherein the R? Q is 3 to 10. 4. The method according to any one of claims 1 to 3,
Wherein the treated surface is a blackened surface-treated copper foil having an a * value of an L * a * b * colorimetric system measured according to JIS Z 8729 (2004) and JIS Z 8722 (2009) 5. The method according to any one of claims 1 to 4,
The treated surface is a blackened surface-treated copper having an average height Rc of roughness curved elements measured according to JIS B 0601 (2001) of 0.1 to 1.0 μm. 6. The method according to any one of claims 1 to 5,
Wherein the treated surface has an arithmetic mean roughness Ra measured according to JIS B 0601 (2001) of 0.10 to 0.35 占 퐉. 7. The method according to any one of claims 1 to 6,
Wherein the copper particles are made of copper and inevitable impurities. 8. The method according to any one of claims 1 to 7,
When the blackened surface-treated copper foil is bonded to one side of a polyethylene terephthalate resin film having a thickness of 100 占 퐉 on the side of the treated surface and the copper foil is removed by etching, the remaining polyethylene terephthalate resin film is not more than 60% Blackened surface treated copper foil with haze value. 9. The method according to any one of claims 1 to 8,
A blackened surface-treated copper foil having a thickness of 0.1 to 18 탆. 10. The method according to any one of claims 1 to 9,
Blackened surface treated copper foil used as wiring material for touch panel sensors. A carrier foil comprising a carrier foil, a peel layer provided on the carrier foil, and a blackened surface-treated copper foil according to any one of claims 1 to 10, Attached copper foil.

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