TWI568894B - Black surface treatment of copper foil and copper foil with carrier foil - Google Patents

Description

Blackened surface treated copper foil and copper foil with carrier foil

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

In recent years, touch panels have been used in operation units of various electric appliances such as mobile phones and mobile data terminals. The touch panel is an electronic component in which an input device capable of detecting a contact position such as a fingertip or a pen tip is combined on a screen of a display panel such as a liquid crystal display device, and the operation sequence of the user is viewed from the screen while the input operation is easy. From the point of view, convenience is high. The touch panel has various types such as a resistive film type or a capacitive type depending on the structure and the detection method.

In particular, the capacitive touch panel is capable of grasping the change in capacitance between the fingertip and the conductive film to detect the position. The use of the finger only allows the finger to be close to the surface of the panel to generate an electrostatic bond, which can achieve the performance of the cursor before the contact. Or operation. There are two types of capacitive type: surface type and projection type. As shown in FIG. 1 , the projection type capacitive touch panel 10 is formed by laminating two transparent electrode layers 12 and 12 ′ each patterned in the x-axis direction and the y-axis direction so as to sandwich the insulating layer 14 . Detected by changes in capacitance between electrodes By measuring the position of the touch, multi-point detection can be performed with high precision, so mobile devices such as smart phones are often used. Further, in Fig. 1, the laminate of the transparent electrode layer 12 / the insulating layer 14 / the transparent electrode layer 12' is sandwiched by the glass substrate 16 and the protective cover 18.

In recent years, it has been proposed in the literature to process copper foil into stripe-like or mesh-shaped copper wiring in a capacitive touch panel to replace the ITO (indium tin oxide) transparent electrode which has been widely used in the past. Since such a copper wiring has a lower electric resistance than the ITO transparent electrode, it is possible to realize a touch panel having higher sensitivity and excellent stability during operation. For example, Patent Document 1 (JP-A-2013-206315) discloses a touch panel sensor having a stripe-like or mesh-shaped copper wiring in a portion required for see-through of the front and back surfaces of the film. In the touch panel sensor of Patent Document 1, the copper wiring is blackened by the oxide film on the viewing side, and the copper wiring is reduced by the copper wiring, which is caused by the specular reflection of the metal. By reflecting, when the touch panel sensor is mounted on the display, the contrast can be suppressed from being lowered. In addition, the formation of the stripe-like or mesh-shaped copper wiring is performed by photolithography and etching of the copper foil by laminating the copper foil to the film, and then viewing the copper wiring. The side is treated with an alkali solution for blackening.

On the other hand, it is also known that a copper foil which is subjected to blackening or browning treatment can be used as a copper foil for shielding electromagnetic waves for electromagnetic waves on the front panel of a plasma display. For example, Patent Document 2 (WO2007/007870) discloses a surface-treated copper foil provided with a nickel-based blackened surface or a cobalt-based blackened surface on the surface of an untreated copper foil. In addition, Patent Document 3 (Japan Special Japanese Laid-Open Patent Publication No. 2005-187913 discloses a browned surface-treated copper foil having a brown surface formed by multi-stage copper plating.

[Previous Technical Literature] [Patent Document]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2013-206315

[Patent Document 2] International Publication No. 2007/007870

[Patent Document 3] Japanese Patent Laid-Open Publication No. 2005-187913

Incidentally, if a surface-treated copper foil which has been previously blackened or browned as disclosed in the cited document 2 or the cited document 3 can be used as a wiring material for a touch panel sensor, it is possible to eliminate the need for additional blackening treatment. . On the other hand, the copper wiring such as the stripe shape of Patent Document 1 is formed by etching away the copper foil. Therefore, in order to make the image displayed on the touch panel such as a liquid crystal display device clear, the focus is on securing the film (for example, The resin film of a PET film or the like) is transparent at the place where the copper foil is etched. This is because when the copper foil is etched, the surface of the film inherits the surface profile of the surface roughness of the copper foil, etc., so the transparency of the film (hereinafter referred to as the transparency of the film after the copper foil etching) is significantly affected by the surface profile of the copper foil. influences. In the surface-treated copper foil described in Patent Document 2, the transparency of the film is excellent after the copper foil is etched, but a nickel-based blackening treatment or a cobalt-based method which is less soluble in copper than the copper in the copper etching solution is applied. Blackening treatment, so line deviation occurs during etching, or copper etching solution is contaminated and difficult To control the liquid concentration. In addition, the surface-treated copper foil described in the patent document 3 does not contain a dissimilar metal which is a main cause of the etching on the surface of the browning treatment. Therefore, in the etching such as the blackening treatment of Patent Document 2, the line deviation is less likely to occur. However, in the multi-stage coking plating, the transparency of the film after the copper foil etching is deteriorated, so that the backlight portion is scattered, and the image of the liquid crystal display portion is hardly presented.

The inventors of the present invention have found that the copper foil is blackened by the use of fine roughening of copper particles, whereby the unevenness and the slope of the treated surface are reduced, and the stripe for processing into a touch panel is bonded to the resin film. In the case of the mesh wiring, the transparency of the film after the copper foil etching can be improved, and black which is required to reduce the visibility of the stripe or the mesh wiring can be realized.

Therefore, an object of the present invention is to provide a blackened surface-treated copper foil which can improve the transparency of a film after etching of a copper foil in the case where the resin film is bonded to a stripe or mesh wiring for a touch panel, and It is a black that is very much needed to reduce the visibility of stripes or mesh wiring, and is suitable for the use of electrode materials for touch panels. Further, 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 an aspect of the present invention, there is provided a blackened surface-treated copper foil which has a blackened surface-treated copper foil having a blackened treated surface by using a fine roughening of copper particles, and the aforementioned treatment surface is based on JIS B 0601 (2001), the measured root mean square slope R Δq of the roughness curve is 25 or less, and according to JIS Z 8729 The luminance L* of the L*a*b* chromaticity system measured by (2004) and JIS Z 8722 (2009) is 30 or less.

According to another aspect of the present invention, a copper foil with a carrier foil comprising a carrier foil, a release layer provided on the carrier foil, and a surface provided on the release layer with the treatment surface outside is provided. The invention has a blackened surface treated copper foil.

10‧‧‧Projected capacitive touch panel

12, 12'‧‧‧ transparent electrode layer

14‧‧‧Insulation

16‧‧‧ glass substrate

18‧‧‧ protective cover

24‧‧‧film

22, 22'‧‧‧ copper wiring

22a, 22a’‧‧‧ blackened surface

FIG. 1 is a view 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.

FIG. 2B is a view showing another example of the copper wiring for the touch panel.

Blackened surface treated copper foil

The copper foil of the present invention is a blackened surface treated copper foil. The blackened surface-treated copper foil has a treated surface which is blackened by the use of fine roughening of copper particles. By using the fine roughening of the copper particles to be blackened, the roughness of the roughness curve of the treated surface is small, and the uneven slope is particularly small. The treatment surface having a small unevenness slope can be defined by a square root mean square slope RΔq of a roughness curve measured in accordance with JIS B 0601 (2001) of 25 or less. By reducing the slope of the unevenness, that is, RΔq, it is processed into a resin film (for example, a PET film) to form a stripe for a touch panel or In the case of the mesh wiring, the transparency of the film after the copper foil etching can be remarkably improved. As described above, in order to vividly display an image displayed on a touch panel such as a liquid crystal display device, the focus is on ensuring the transparency of the film after the copper foil is etched, and by using the blackened surface-treated copper foil of the present invention, The transparency of this film. Moreover, the blackened surface-treated copper foil can achieve black which is highly desirable for reducing the visibility of the stripe or the mesh wiring, and this characteristic can be obtained by L* measured in accordance with JIS Z 8729 (2004) and JIS Z 8722 (2009). The brightness L* of the a*b* chromaticity system is specified to be 30 or less. As described above, the copper wiring has a specular reflection characteristic of the metal itself, and the reflectance is high. As described above, the luminance is L* by the blackening, and the displayed image can be displayed when the touch panel sensor is mounted on the display. Bright. According to the present invention, it is possible to provide a blackened surface-treated copper foil which can improve the transparency of the film after etching of the copper foil in the case of being processed into a stripe or mesh wiring for a touch panel by being bonded to a resin film. And it can achieve black that is very much needed to reduce the visibility of stripes or mesh wiring.

Therefore, the blackened surface-treated copper foil of the present invention is preferably used for a wiring material for a touch panel inductor, and the electric resistance is lower than that of an ITO transparent electrode widely used in a touch panel sensor, and is a better alternative material. When the blackened surface-treated copper foil of the present invention is used for a wiring material for a touch panel sensor, as shown in FIG. 2A, in the structure in which the copper wiring 22 and the film 24 are laminated, it is preferable to use The blackened treatment surface 22a is disposed toward the viewing side (the side of the film 24 in Fig. 2A). Further, as shown in Fig. 2B, the copper wirings 22, 22' may be laminated on both sides of the film 24. In this case, at least the upper copper wiring 22' should be The blackened processing surface 22a' is disposed so as to face the viewing side (the side of the wiring 22' with respect to the film 24 in FIG. 2B), and the blackened copper wirings 22, 22' may be blackened. The treatment surfaces 22a, 22a' are oriented towards the viewing side. 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 viewing side.

The blackened surface-treated copper foil of the present invention has a blackened treated surface by using fine roughening of copper particles. As described above, since the blackened surface of the present invention is composed of copper particles, it is excellent in etching property. Further, it is possible to solve the problem that the nickel-based blackening treatment or the cobalt-based blackening treatment which is less soluble in copper in the copper etching solution than in the copper etching liquid, which causes the line deviation or the copper etching liquid to be contaminated, and the liquid is difficult to control. Concentration of these shortcomings. Therefore, the copper particles are preferably composed of copper and unavoidable impurities. The particle diameter of the copper particles is not particularly limited. This is because the particle size of the copper particles is reflected in the surface root mean square slope R Δq of the roughness curve, the average height Rc of the roughness curve element, the arithmetic mean roughness Ra, etc., as long as the evaluation by these parameters is sufficient. . Nevertheless, it is considered that the particle diameter of the copper particles is preferably from 10 nm to 250 nm. The shape of the copper particles is not particularly limited, and is preferably slightly spherical from the viewpoint of effectively preventing chipping.

The treated surface of the blackened surface-treated copper foil of the present invention has a root mean square slope R?q of a roughness curve of 25 or less. R Δq is a square root of the local slope dZ/dx in the reference length l of the roughness curve measured according to JIS B 0601 (2001), and is defined according to the following formula.

In this manner, R Δq is a parameter for averaging the unevenness, and clearly indicates the presence or absence of the tumor on the treated surface. That is, if RΔq is too high, it means that the nodules or the irregularities are too large, and the transparency of the film after the copper foil etching is deteriorated. In this regard, when RΔq is 25 or less, the nodules or irregularities on the treated surface become small, and thus the transparency of the film after copper foil etching is improved. A suitable RΔq is 3 to 25, more preferably 3 to 10, particularly preferably 3 to 8, and most preferably 4 to 7. In 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 be blackened by the nodules.

The treated surface of the blackened surface-treated copper foil of the present invention has a brightness L* of 30 or less, preferably 20, in accordance with JIS Z 8729 (2004) and JIS Z 8722 (2009). Hereinafter, it is preferably 15 or less, more preferably 13 or less. The lower limit value is not particularly limited, and is, for example, 0.5 or more. The lower the brightness L* value, the darker the color, and the higher the value, the whiter it is. In this case, when the resin film is processed into a stripe or mesh wiring for a touch panel in the above range, the visibility of the stripe or the mesh wiring can be more effectively reduced. As a result, when the touch panel sensor is mounted on the display, the displayed image can be made sharp.

The treated surface of the blackened surface-treated copper foil of the present invention is measured in accordance with JIS Z 8701 (1999) and JIS Z 8722 (2009). The Y value of the XYZ chromaticity system is preferably 10 or less, preferably 5 or less. The lower limit value is not particularly limited, but is usually 0.5 or more. The Y value is called the visual reflectance and is a parameter that simultaneously represents green and reflectance. In particular, from the viewpoint that the reflectance is lowered, as a result, it is possible to effectively prevent or suppress the reflection of the sensor of the display unit and to observe the phenomenon of white appearance, the Y value is preferably 10 or less.

The treated surface of the blackened surface-treated copper foil of the present invention preferably has an a* value of 4 or less in accordance with the L*a*b* chromaticity system measured in accordance with JIS Z 8729 (2004) and JIS Z 8722 (2009). It is -5 to 3, more preferably -3 to 2. The higher the a* value of the L*a*b* chromaticity system, the more reddish the hue, and the tendency for the naked eye to be seen in red. In this regard, in the use of the wiring material for the touch panel sensor, if the a* value is in the range as described above, it is considered to be more suitable from the viewpoint that the red color is not emphasized and the wiring becomes less noticeable. Tone.

The treated surface of the blackened surface-treated copper foil of the present invention has an average height Rc of 0.1 to 1.0 μm, preferably 0.1 to 0.8 μm, more preferably 01, as measured by JIS B 0601 (2001). ~0.5μm, particularly preferably 0.2~0.4μm. In the case where the resin film is processed into a stripe or mesh wiring for a touch panel in the above range, the circuit is not easily peeled off, and the linearity of the circuit pattern can be easily realized.

The treated surface of the blackened surface-treated copper foil of the present invention preferably has an arithmetic mean roughness Ra of from 010 to 0.35 μm, preferably from 0.15 to 0.25 μm, more preferably from 0.20 to 0.25 μm, measured according to JIS B 0601 (2001). . If it is in the above range, the film is not easily peeled off when the resin film is processed into a stripe or mesh wiring for a touch panel. It is also easy to realize the linearity of the circuit pattern.

In the blackened surface-treated copper foil of the present invention, the blackened surface-treated copper foil is bonded to one side of a polyethylene terephthalate resin (PET) film having a thickness of 100 μm by the treatment surface side, and then removed by etching. In the case of a copper foil, the residual polyethylene terephthalate resin film preferably has a haze value of 60% or less, preferably 50% or less, more preferably 45% or less, and particularly preferably 20%. Hereinafter, the optimum is 10% or less. The lower limit value is not particularly limited, and is, for example, 1% or more. The haze value means the degree of blurring, so the low haze value as described above means high transparency. Therefore, the blackened surface-treated copper foil having such a structure can improve the transparency of the film after the copper foil etching in the case where the resin film is bonded to the stripe or mesh wiring for the touch panel. Further, the haze value was obtained by subjecting a blackened surface-treated copper foil to a PET film (thickness: 100 μm) by thermocompression bonding to prepare a copper-clad laminate, and then etching the surface-treated copper foil to remove commercially available haze. The haze value (Haze: unit %) of three films at 23 ° C was measured for the residual PET film according to JIS K 7136 (2000) and determined according to JIS K 7136 (2000). The average value is sufficient.

The thickness of the blackened surface-treated copper foil of the present invention is not particularly limited, but is preferably 0.1 to 18 μm, preferably 0.5 to 10 μm, more preferably 0.5 to 7 μm, particularly preferably 0.5 to 5 μm, and most preferably 0.5 to 3 μm. Further, the blackened surface-treated copper foil of the present invention is not limited to a copper foil which is roughened to the surface of a normal copper foil, and the surface of the copper foil of the copper foil with a carrier foil may be blackened.

Method for producing blackened surface treated copper foil

An example of a suitable method for producing a blackened surface-treated copper foil of the present invention will be described. However, the blackened surface-treated copper foil of the present invention is not limited to the method described below, and as long as fine graining using copper particles is performed, Items made by various methods are acceptable.

(1) Preparation of copper foil

As the copper foil used for producing the blackened surface-treated copper foil, both an electrolytic copper foil and a rolled copper foil can be used. Further, the copper foil may be a copper foil which is not roughened or a copper foil which is pre-roughened. The thickness of the copper foil is not particularly limited, and is preferably 0.1 to 18 μm, more preferably 0.5 to 10 μm, still more preferably 0.5 to 7 μm, particularly preferably 0.5 to 5 μm, and most preferably 0.5 to 3 μm. When the copper foil is prepared in the form of a copper foil with a carrier foil, the copper foil can be dried by a wet film formation method such as electroless copper plating or copper plating, sputtering, or chemical vapor deposition. A film method or a combination of these is formed.

The maximum height difference (Wmax) of the surface roughness of the copper foil which is finely roughened by the copper particles is preferably 2.0 μm or less, preferably 1.2 μm or less, more preferably 0.8 μm or less. The lower limit value is not particularly limited, and is, for example, 0.1 μm or more. When it is in the above range, when the copper particles are finely roughened, the slope of the unevenness defined by the root mean square slope RΔq of the roughness curve can be reduced, and the film can be processed into a touch panel by bonding to a resin film (for example, a PET film). In the case of stripe or mesh wiring, the transparency of the film after copper foil etching can be remarkably improved. In addition, "the maximum height difference of the undulation (Wmax) is the maximum value of the waveform in the waveform data obtained by filtering the waveform data associated with the undulation by the information obtained by using the three-dimensional surface structure analysis microscope. For example, the measurement machine uses zygo New View 5032 (manufactured by Zygo Co., Ltd.), the analysis software uses Metro Pro Ver. 8.0.2, and the low frequency filter is measured under the condition of 11 μm.

(2) Black roughening

At least one surface of the copper foil is blackened by using fine roughening of the copper particles. This black roughening is performed by electrolysis using a copper electrolytic solution for black roughening. A suitable copper electrolytic solution for black roughening 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 speed of the copper particles becomes slow, and the industrially required productivity is not satisfied, which is not suitable. On the other hand, when the copper concentration exceeds 20 g/L, it is close to the current density described later, and it is close to the conditions of smooth plating, and it is difficult to achieve black roughening, which is not suitable. Further, the concentration of free sulfuric acid is related to the concentration of copper. When the concentration is out of this concentration range, the electrification characteristics at the time of electrolysis change, and it is difficult to achieve good black roughening, which is not suitable.

In the copper electrolytic solution for black roughening, it is preferable to further add an additive to control fine roughening. Suitable examples of such an additive 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 The materials should be added to the black electrolytic copper electrolytic solution at a concentration of 10 to 500 ppm. The sodium polyacrylate is preferably added to the black electrolytic copper electrolytic solution at a concentration of 10 to 1000 ppm. In this manner, by adding the additives singly or appropriately, it is possible to suppress the growth of the acicular particles and form the spherical fine roughened particles.

The electrolysis of the copper electrolytic solution for black roughening is preferably carried out by polarizing the copper foil into a cathode in an electrolyte having a solution temperature of 20 to 40 ° C, and performing the current density of 30 to 100 A/dm ² for 2 to 10 sec. . If the solution temperature is less than 20 ° C, the shape of the formed roughened particles tends to vary, which is not suitable. On the other hand, when the temperature of the solution exceeds 40° C., the solution properties of the copper electrolytic solution for black roughening tend to change, and there is a tendency that the fine roughening tends not to be stabilized, which is not preferable. In addition, when the current density is less than 30 A/dm ² , the black roughening cannot be sufficiently performed, and the luminance L* of the black rough surface is hardly set to 30 or less, which is not suitable. On the other hand, when the current density exceeds 100 A/dm ² , the deposition rate of the fine copper particles is too fast, and the shape of the formed copper particles cannot be a good spherical body, which is not suitable.

(3) Anti-rust treatment

According to the demand, the black roughened copper foil can also be subjected to rustproof treatment. The rustproof treatment is preferably an electroplating treatment involving the use of zinc. The zinc plating treatment can be either zinc plating treatment or zinc alloy plating treatment, and zinc alloy plating treatment is particularly preferable for zinc-nickel alloy treatment. The zinc-nickel alloy treatment may be performed by plating treatment containing at least Ni and Zn, and may further contain Other elements such as Sn, Cr, Co, and the like. The Ni/Zn adhesion ratio in the zinc-nickel alloy plating is preferably 1.2 to 10, preferably 2 to 7, more preferably 2.7 to 4 in terms of mass ratio. Further, the rustproof treatment preferably further includes a chromate treatment which is preferably carried out on the surface of the zinc-containing plating after the plating treatment using zinc. Thereby, the rust prevention property can be further improved. A particularly suitable rust-preventing treatment is a combination of a zinc-nickel alloy plating treatment followed by a subsequent chromate treatment.

(4) decane coupling agent treatment

The copper foil may be subjected to a decane coupling agent treatment according to requirements, and a decane coupling agent layer may also be formed. Thereby, moisture resistance, chemical resistance, adhesion to an adhesive, etc. can be improved. The decane coupling agent layer can be formed by appropriately diluting, coating, and drying the decane coupling agent. Examples of the decane coupling agent include an epoxy functional decane coupling agent such as 4-glycidylbutyltrimethoxy decane or γ-glycidoxypropyltrimethoxy decane, or γ-aminopropyl hydride. Ethoxy decane, N-β (aminoethyl) γ-aminopropyltrimethoxydecane, N-3-(4-(3-aminopropoxy)butoxy)propyl-3-amine-propyl An amino functional decane coupling agent such as a methoxymethoxy decane or an N-phenyl propyl propyl trimethoxy decane, or a thiol functional decane coupling agent such as γ-mercaptopropyltrimethoxy decane or a vinyl trimethyl An olefin functional decane coupling agent such as oxydecane or vinylphenyltrimethoxy decane, or an acrylic functional decane coupling agent such as γ-methacryloxypropyltrimethoxydecane or an imidazolium or the like An imidazole-functional decane coupling agent or a triazine-functional decane coupling agent such as triazine decane.

Copper foil with carrier 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. In particular, when the image of the display when the touch panel sensor is mounted on the display is sharp, and the circuit pattern width is set to be narrow or the height of the copper wiring is set to 5 μm or less, it is necessary to use a thin copper foil. Therefore, it is preferable to use a copper foil with a carrier from the viewpoint of operability improvement. In this case, the copper foil with a carrier foil is provided with a carrier foil, a peeling layer provided on the carrier foil, and the blackened surface-treated copper foil of the present invention provided on the peeling layer so that the blackened surface is outside. Made. Of course, the copper foil with a carrier foil may be formed of a well-known layer in addition to the blackened surface-treated copper foil of the present invention.

The carrier foil is a foil used to support the blackened surface-treated copper foil to improve its operability. Examples of the carrier foil include an aluminum foil, a copper foil, a resin film whose surface is metal-coated, and the like, and are preferably a copper foil. The copper foil may be any of a rolled copper foil and an electrolytic copper foil. The thickness of the carrier foil is usually 200 μm or less, preferably 18 μm to 200 μm.

The release layer is a layer having a function of reducing the peel strength of the carrier foil and ensuring the strength, and further suppressing the mutual diffusion between the carrier foil and the copper foil during the calender molding at a high temperature. The release layer is generally formed on one side of the carrier foil, and may be formed on both sides. The release layer may be either an organic release layer or an inorganic release 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. Nitrogen-containing organication Examples of the compound include a triazole compound, an imidazole compound, and the like, and are particularly preferably a triazole compound from the viewpoint of easy removability. Examples of the triazole compound include 1,2,3-benzotriazole, carboxybenzotriazole, N', N'-bis(benzotriazolmethyl)urea, and 1H-1,2,4- Triazole and 3-amino-1H-1,2,4-triazole and the like. Examples of the sulfur-containing organic compound include mercaptobenzothiazole, trimeric thiocyanate, 2-benzimidazolethiol, and the like. Examples of the carboxylic acid include a monocarboxylic acid, a dicarboxylic acid, and the like. 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. Further, the formation of the release layer may be carried out by bringing at least one surface of the carrier foil into contact with a solution containing the release layer component, and fixing the release layer component to the surface of the carrier foil or the like. The contact between the carrier foil and the solution containing the release layer component may be carried out by dipping in a solution containing the release layer component, spraying of a solution containing the release layer component, dripping of a solution containing the release layer component, or the like. Further, the fixing of the peeling layer component on the surface of the carrier foil may be carried out by drying of the solution containing the peeling layer component, electrodeposition of the peeling layer component in the solution containing the peeling layer component, or the like. The thickness of the release layer is usually from 1 nm to 1 μm, preferably from 5 nm to 500 nm.

The blackened surface-treated copper foil is the blackened surface-treated copper foil of the present invention described above. The blackened surface-treated copper foil of the present invention is a product which is subjected to fine roughening (blackening) using copper particles in the order of first forming a copper layer as a copper foil on the surface of the peeling layer, and then at least finely roughening ( Black)). The details of the fine roughening (blackening) are as described above. In addition, the copper foil is preferably an advantage of being able to exhibit a copper foil with a carrier. It is constructed in the form of an extremely thin copper foil. A suitable thickness of the ultra-thin copper foil is from 0.1 μm to 7 μm, preferably from 0.5 μm to 5 μm, more preferably from 0.5 μm to 3 μm.

Other functional layers may also be provided between the release layer and the copper foil. Examples of such other functional layers include an auxiliary metal layer. The auxiliary metal layer is preferably composed of nickel and/or cobalt. The thickness of the auxiliary metal layer should be set at 0.001 to 3 μm.

[Examples]

The invention is further illustrated 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

The copper electrolyte is a sulfuric acid acidic copper sulfate solution having the composition shown below, the cathode is a titanium rotating electrode having a surface roughness Ra of 0.20 μm, and the anode is a DSA (size stable anode) at a solution temperature of 45 ° C and a current density of 55 A/ electrolysis, the electrolytic copper foil having a thickness of 12μm in dm ^2.

The maximum height difference (Wmax) of the undulation of the deposition surface of this electrolytic copper foil was 0.8 μm, and the maximum height difference (Wmax) of the undulation of the electrode surface was 1.5 μm.

<Composition of sulfuric acid acidic copper sulfate solution>

- Copper concentration: 80g//L

- Free sulfuric acid concentration: 140g/L

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

- Diallyldimethylammonium chloride polymer concentration: 50mg/L

- Chlorine concentration: 40mg/L

<Maximum height difference (Wmax) of undulation>

The measuring machine was zygo New View 5032 (manufactured by Zygo Co., Ltd.), the analysis software was Metro Pro Ver. 8.0.2, and the low frequency filter was used under the condition of 11 μm to measure the maximum height difference (Wmax) of the undulation. In this case, the surface to be measured and the sample holder of the surface-treated copper foil are adhered to each other and fixed. In the range of 1 cm square of the sample piece, 6 points are selected from the field of view of 108 μm × 144 μm, and the measurement points are measured from 6 places. The average value of the maximum height difference (Wmax) of the obtained undulation is taken as a representative value.

(2) Black roughening

In the electrode surface and the deposition surface of the electrodeposited copper foil, the copper electrolytic solution for black roughening having the following composition was used for the deposition surface side, and the solution temperature was 30 ° C, the current density was 50 A/dm ² , and the time was 4 sec. Under electrolysis, black roughening is performed.

<Composition of copper electrolytic solution for black roughening>

- Copper concentration: 13g/L

- Free sulfuric acid concentration: 70g/L

- Chlorine concentration: 35mg/L

- Polyethylene glycol concentration: 100ppm

- Bis(3-sulfopropyl) disulfide concentration: 100 ppm

(3) Anti-rust treatment

The rust-preventing treatment consisting of inorganic rust-proof treatment and chromate treatment is performed on both surfaces of the blackened roughened electrodeposited copper foil. First, zinc is used in the inorganic rust-preventing treatment using a pyrophosphoric acid bath, a potassium pyrophosphate concentration of 80 g/L, a zinc concentration of 0.2 g/L, a nickel concentration of 2 g/L, a liquid temperature of 40 ° C, and a current density of 0.5 A/dm ² . - Nickel alloy anti-rust treatment. Next, the chromate treatment is to further form a chromate layer after the zinc-nickel alloy anti-rust treatment. This chromate treatment was carried out under the conditions of a chromic acid concentration of 1 g/L, a pH of 11, a solution temperature of 25 ° C, and a current density of 1 A/dm ² .

(4) decane coupling agent treatment

The copper foil subjected to the above rust-preventing treatment was washed with water, and immediately subjected to a decane coupling agent treatment to adsorb the decane coupling agent to the rust-preventing treatment layer of the black roughened surface. The decane coupling agent is treated by applying a solution having a concentration of 3-aminopropyltrimethoxydecane of 3 g/L in a solvent of pure water to a black roughened surface by a showerhead. . After the adsorption of the decane coupling agent, the water was finally evaporated by an electric heater to obtain a blackened surface-treated copper foil having a thickness of 12 μm.

(5) Evaluation

With respect to the obtained blackened surface-treated copper foil, various characteristics were evaluated as described below.

<Surface characteristic parameters (RΔq, Rc, and Ra)>

The optical measuring apparatus was subjected to a laser microscope (OLS 4100, manufactured by Olympus), and surface characteristic parameters RΔq, Rc and Ra of the surface-treated copper foil were measured in accordance with JIS B 0601 (2001). In this measurement, the evaluation length was set to 642 μm, and the measurement was performed in the width direction of the copper foil. Here, the width direction of the copper foil corresponds to the width direction (TD direction) of the rotating cathode at the time of production of the electrolytic copper foil.

<Luminance L*, Chroma a* and Y value>

Luminance L* and chromaticity a* were measured in accordance with JIS Z 8729 (2004) and JIS Z 8722 (2009) using a spectrophotometer (SE6000, manufactured by Nippon Denshoku Industries Co., Ltd.) in accordance with JIS Z 8701 (1999) and JIS. Z 8722 (2009) measures the Y value.

<Haze value>

A surface-treated copper foil and a PET film (thickness: 100 μm) were thermocompression bonded to form a copper-clad laminate. Then, the surface-treated copper foil was removed by etching, and a residual haze meter was used, and a haze meter (NDH5000, manufactured by Nippon Denshoku Industries Co., Ltd.) was used, and three places were measured at 23 ° C according to JIS K 7136 (2000). Haze value of the film (Haze: single Bit %), find the average.

Example 2

The production and evaluation of the blackened surface-treated copper foil were carried out in the same manner as in Example 1 except that the electrode surface side of the electrodeposited copper foil was subjected to black roughening.

Example 3

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

(1) Production of carrier foil

In the copper electrolyte, a sulfuric acid acidic copper sulfate solution having the composition shown below was used, a cathode made of titanium having a surface roughness Ra of 0.20 μm was used for the cathode, and a DSA (size stability anode) was used for the anode, and the solution temperature was 45 ° C and the current density was 55 A/ Electrolysis was carried out under the conditions of dm ² to obtain an electrolytic copper foil having a thickness of 12 μm as a carrier foil.

<Composition of sulfuric acid acidic copper sulfate solution>

- Copper concentration: 80g/L

- Free sulfuric acid concentration: 140g/L

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

- Diallyldimethylammonium chloride polymer concentration: 50mg/L

- Chlorine concentration: 40mg/L

(2) Formation of organic peeling layer

The acid-washed carrier was used on the electrode surface side of the copper foil in a CBTA aqueous solution containing 1000 ppm by weight of CBTA (carboxybenzotriazole), 150 g/l of sulfuric acid, and 10 g/l of copper at a liquid temperature of 30 ° C. After immersing for 30 seconds and then picking up, the CBTA component was adsorbed to the electrode face of the carrier foil. In this manner, a CBTA layer was formed as an organic release layer on the surface of the shiny side of the copper foil for carrier.

(3) Formation of auxiliary metal layer

The carrier in which the organic release layer was formed was immersed in a copper foil containing 20 g/l of nickel and 300 g/l of potassium pyrophosphate prepared by using nickel sulfate at a liquid temperature of 45 ° C, a pH of 3, and a current density of 5 A/dm ^{2 .} Under the conditions, nickel corresponding to an adhesion amount of 0.002 μm in thickness was attached to the organic release layer. In this manner, a nickel layer is formed on the organic release layer as an auxiliary metal layer.

(4) Formation of extremely thin copper foil

The carrier which forms the auxiliary metal layer was immersed in an acidic copper sulfate solution with a copper foil, and electrolyzed under smooth plating conditions of a current density of 8 A/dm ² for 60 seconds to form an ultra-thin copper foil having a thickness of 3 μm on the auxiliary metal layer. The maximum height difference (Wmax) of the undulation of the deposition surface of this ultra-thin copper foil was 1.1 μm.

(5) Black roughening

The copper thinning solution for black roughening having the composition shown below was electrolyzed under the conditions of a solution temperature of 30 ° C, a current density of 50 A/dm ² , and a time of 4 sec, and blackening was performed on the deposition surface of the ultra-thin copper foil.

<Composition of copper electrolytic solution for black roughening>

- Copper concentration: 13g/L

- Free sulfuric acid concentration: 70g/L

- Chlorine concentration: 35mg/L

- Sodium polyacrylate concentration: 400ppm

(6) Anti-rust treatment

The rust-preventing treatment consisting of inorganic rust-proof treatment and chromate treatment was performed on both sides of the ultra-thin copper foil with the carrier foil after the black roughening. First, zinc is used in the inorganic rust-preventing treatment using a pyrophosphoric acid bath, a potassium pyrophosphate concentration of 80 g/L, a zinc concentration of 0.2 g/L, a nickel concentration of 2 g/L, a liquid temperature of 40 ° C, and a current density of 0.5 A/dm ² . - Nickel alloy anti-rust treatment. Next, the chromate treatment is to further form a chromate layer after the zinc-nickel alloy anti-rust treatment. This chromate treatment was carried out under the conditions of a chromic acid concentration of 1 g/L, a pH of 11, a solution temperature of 25 ° C, and a current density of 1 A/dm ² .

(7) decane coupling agent treatment

The copper foil subjected to the above rust-preventing treatment was washed with water, and immediately subjected to a decane coupling agent treatment to adsorb the decane coupling agent to the rust-preventing treatment layer of the black roughened surface. The decane coupling agent is treated by using a solution containing pure water as a solvent and a concentration of 3-aminopropyltrimethoxydecane of 3 g/L. The solution is sprayed onto the black roughened surface to carry out an adsorption treatment. After the decane coupling agent was adsorbed, the 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 having a thickness of 3 μm.

(8) Evaluation

Each of the characteristics was evaluated in the same manner as in Example 1 for the copper foil with a carrier foil having the obtained blackened surface-treated copper foil.

Example 4 (comparative)

The production and evaluation of the browned surface-treated copper foil were carried out in the same manner as in Example 1 except that the following browning treatment was carried out on the electrode surface side of the electrodeposited copper foil.

<Browning treatment>

First, an electrolytic copper foil (an article prepared in Example 1 (1)) which was not subjected to the roughening treatment was immersed in a dilute sulfuric acid solution having a sulfuric acid concentration of 150 g/liter and a liquid temperature of 30 ° C for 30 seconds to carry out surface purification. . The browning treatment was carried out by sequentially performing the steps (a) to (e) shown below on the electrolytic copper foil purified in this manner.

(a) Basic plating process steps

On the electrode surface side of the above-mentioned electrodeposited copper foil, a copper sulfate-based plating solution was used, and a base plating treatment for making the surface of the copper foil brown was performed in accordance with the conditions of coking plating. This base plating treatment was carried out by electrolysis under a coking 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/liter, and a liquid temperature of 25 °C. As a result, in the coking plating performed in the basic plating step, only a core for forming a certain degree of irregularities on the surface of the copper foil was formed, and the electrodeposition amount was 300 mg/m ^{2 in} terms of a converted thickness.

(b) Additional plating process steps

For the surface of the copper foil subjected to the basic plating treatment in this manner, a copper sulfate-based plating solution was used, and a plating treatment was performed in accordance with the coking plating conditions. The additional plating treatment at this time is carried out using a copper sulfate solution having the same concentration and liquid temperature as the above step (a). At this time, the current density (Ib) used for the coking plating is set to 15% of the current density Ia to be 1.5 A/dm ² to prevent current concentration in the core formed on the surface of the copper foil in the step (a). And prevent useless abnormal precipitation. The amount of electrodeposition in this additional plating step was determined as the amount of electrodeposition in which the thickness was 50 mg/m ² .

(c) coating plating process steps

For the copper foil surface on which coking plating was carried out in this manner, a copper plating solution was used, and a coating plating treatment was performed in accordance with smooth plating conditions. This coating 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/liter, and a liquid temperature of 45 ° C in a smooth plating condition of a current density of 15 A/dm ² . In this manner, the surfaces roughened in steps (a) and (b) are smoothed. At this time, in terms of the thickness of the plating is smooth 4g / m ^2.

(d) modification plating process steps

With respect to the surface on which the smooth plating treatment was carried out in this manner, a copper plating solution was used, and a surface of the copper foil was subjected to a modified plating treatment in accordance with the coking plating conditions, whereby extremely fine copper particles were adhered and formed. The formation of the ultrafine copper particles is carried out by adding 9-phenyl acridine and having a copper concentration of 13 g/l, a free sulfuric acid of 50 g/l, a 9-phenyl acridine of 150 mg/l, a chlorine concentration of 28 ppm, and a liquid. The copper sulfate solution at a temperature of 35 ° C was carried out under the electrolysis conditions of a current density of 24 A/dm ² . The amount of electrodeposition in this modified plating treatment step was determined as the amount of electrodeposition in which the thickness was 300 mg/m ² .

(e) Washing and drying steps

The copper foil which was subjected to the modified plating in this manner was sufficiently sprayed with pure water, washed, and stored in a drying oven having a gas ambient temperature of 150 ° C for 4 seconds by an electric heater to evaporate water, thereby obtaining The surface treated copper foil of the browned surface. Further, the water washing is not limited to this step, and is suitably carried out between the above steps in such a manner that the solution of the previous step is not brought into the subsequent step.

Example 5 (comparative)

The production and evaluation of the surface-treated copper foil were carried out in the same manner as in Example 2 except that the black roughening was not performed.

result

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

22‧‧‧Bronze wiring

22a‧‧‧Blackened surface

24‧‧‧film

Claims (11)

A blackened surface-treated copper foil having a blackened surface-treated copper foil having a treated surface which is blackened by fine roughening of copper particles, and the aforementioned treated surface is roughened according to JIS B 0601 (2001) The square root mean square slope RΔq of the degree curve is 25 or less, and the luminance L* of the L*a*b* chromaticity system measured according to JIS Z 8729 (2004) and JIS Z 8722 (2009) is 30 or less. The blackened surface-treated copper foil according to claim 1, wherein the Y value of the XYZ chromaticity system measured according to JIS Z 8701 (1999) and JIS Z 8722 (2009) is 10 or less. The blackened surface-treated copper foil according to claim 1, wherein the aforementioned RΔq is 3 to 10. The blackened surface-treated copper foil according to claim 1, wherein the aforesaid treated surface is a* value of the L*a*b* chromaticity system measured according to JIS Z 8729 (2004) and JIS Z 8722 (2009). It is 4 or less. The blackened surface-treated copper foil according to the first aspect of the invention, wherein the average height Rc of the roughness curve element measured according to JIS B 0601 (2001) is 0.1 to 1.0 μm. The blackened surface-treated copper foil according to claim 1, wherein the arithmetic surface roughness Ra measured according to JIS B 0601 (2001) is 0.10 to 0.35 μm. The blackened surface-treated copper foil according to claim 1, wherein the copper particles are composed of copper and unavoidable impurities. The blackened surface-treated copper foil according to the first aspect of the invention, wherein the blackened surface-treated copper foil is attached to one side of a polyethylene terephthalate resin film having a thickness of 100 μm with the aforementioned treated surface side When the copper foil is removed by etching, the residual polyethylene terephthalate resin film has a haze value of 60% or less. The blackened surface-treated copper foil according to the first aspect of the patent application has a thickness of 0.1 to 18 μm. The blackened surface-treated copper foil of claim 1 is used for a wiring material for a touch panel sensor. A copper foil with a carrier foil, comprising: a carrier foil, a release layer provided on the carrier foil, and a coating layer disposed on the release layer on the outer side of the treatment surface, as in any of claims 1 to 10 A blackened surface treated copper foil.