JP3910623B1 - Manufacturing method of electrolytic copper foil, electrolytic copper foil obtained by the manufacturing method, surface-treated electrolytic copper foil obtained using the electrolytic copper foil, copper-clad laminate and printed wiring using the surface-treated electrolytic copper foil Board - Google Patents

Abstract

The present invention provides an electrolytic copper foil having a lower profile and gloss than a low profile electrolytic copper foil that has been supplied to the market.
In order to solve the above problems, the electrolytic copper foil has an ultra-low profile with a surface roughness (Rzjis) of less than 1.0 μm on the surface of the deposited surface regardless of the thickness, and The electrolytic copper foil having a glossiness [Gs (60 °)] of 400 or more is used. This electrolytic copper foil is obtained by adding 3-mercapto-1-propanesulfonic acid and / or bis (3-sulfopropyl) disulfide, a quaternary ammonium salt polymer having a cyclic structure, and chlorine to obtain a sulfuric acid-based copper. It is obtained by electrolysis using an electrolytic solution.
[Selection] Figure 1

Description

The present invention is a method for producing an electrolytic copper foil, an electrolytic copper foil obtained by the production method, a surface-treated electrolytic copper foil obtained by using the electrolytic copper foil, and a copper-clad laminate using the surface-treated electrolytic copper foil The present invention relates to a board and a printed wiring board. In particular, the present invention relates to an electrolytic copper foil having a low profile and high gloss on the surface of the electrolytic copper foil bonded to the insulating layer constituting material.

  Since copper metal is a good electrical conductor, is relatively inexpensive and easy to handle, electrolytic copper foil is widely used as a basic material for printed wiring boards. In addition, electronic and electrical devices in which printed wiring boards are frequently used are required to be so-called light and thin, such as miniaturization and weight reduction. Conventionally, in order to realize such a light, thin and small electronic and electrical device, it is necessary to make the signal circuit a wiring with a fine pitch as much as possible, and manufacturers etc. adopt etching using thinner copper foil. In order to cope with this problem, the setting time of over-etching when forming the wiring is shortened and the etching factor of the wiring to be formed is improved.

  In addition, electronic and electrical devices that are reduced in size and weight are also demanded to be highly functional. Therefore, in order to secure a component mounting area as large as possible within a limited board area due to the spread of the surface mounting method, it has been necessary to take measures to improve the etching factor of the wiring of the printed wiring board. For this purpose, tape automated bonding (TAB) substrates and chip-on-film (COF) substrates, which are so-called interposer substrates that directly mount IC chips and the like, have low profile electrolysis that is more than the usual printed wiring board applications. Copper foil has been sought. Note that the profile is the adhesive surface that is the bonding interface with the insulating layer forming material in the standard for copper foil for printed wiring boards (in the present application, the term “bonding surface” will be unified without using the “bonding interface”) The surface roughness Rzjis is defined by a value measured in the TD direction in accordance with JIS B 0601-2001, and the low profile means that the surface roughness Rzjis of the bonded surface is small.

  In order to solve such a problem, Patent Document 1 discloses that the surface roughness Rz of the deposited surface of the untreated electrolytic copper foil is equal to or smaller than the surface roughness Rz of the glossy surface of the untreated electrolytic copper foil. A surface-treated electrolytic copper foil is disclosed in which a roughening treatment is performed on the deposited surface to form an adhesive surface. For the production of the untreated electrolytic copper foil, an electrolytic solution to which a compound having a mercapto group, chloride ions, a low molecular weight glue having a molecular weight of 10,000 or less and a high molecular weight polysaccharide are added is used. Specifically, the compound having a mercapto group is 3-mercapto 1-propanesulfonate, the molecular weight of the low molecular weight glue is 3000 or less, and the high molecular polysaccharide is hydroxyethyl cellulose.

  Moreover, in patent document 2, in the manufacturing method of the electrolytic copper foil by electrolysis of a sulfuric acid acidic copper plating solution, the sulfuric acid copper plating solution containing the copolymer of a diallyl dialkyl ammonium salt and sulfur dioxide is used. A method for producing an electrolytic copper foil is disclosed. The sulfuric acid copper plating solution preferably contains polyethylene glycol, chlorine and 3-mercapto-1-sulfonic acid. And the precipitation surface roughness used as an adhesive surface with an insulation base material is small, and it is supposed that the low profile whose 10-point average roughness Rz is about 1.0 micrometer +/- 0.5 micrometer will be obtained in the 10-micrometer-thick electrolytic copper foil.

  And when an electrolytic copper foil is manufactured using these manufacturing methods, a low profile precipitation surface is surely formed, and the conventional low profile electrolytic copper foil has good characteristics.

JP 9-143785 A JP 2004-35918 A

  On the other hand, the clock frequency of a personal computer, which is representative of electronic or electric equipment, has increased, and the calculation speed has been dramatically increased. Conventionally, it is not limited to mere data processing, which is the original role as a computer, and a function of using the computer itself in the same manner as an AV device is added. That is, not only a music playback function but also a DVD recording / playback function, a TV image recording function, a videophone function, and the like are added one after another.

  That is, it is not sufficient for a monitor of a personal computer to satisfy a simple data monitoring function, and an image quality that can withstand long-time viewing is required even if an image such as a movie is displayed. And it is demanded to supply such quality monitors at low cost and in large quantities. A liquid crystal monitor is often used for the current monitor, and the tape automated bonding (TAB) substrate or the chip on film (COF) substrate is generally used to mount the driver element of the liquid crystal panel. It is. In order to achieve a high-definition monitor, it is required to form a finer circuit on the driver board to meet the increase in the number of scanning lines. As the panel size increases, efforts have been made to reduce the product dimensions by reducing the width of the outer edge as much as possible. In order to dispose the driver on the back surface, it is necessary to fold and install the TAB substrate or the COF substrate, and from the beginning, the flexibility is also required to be good. In the COF, unlike the TAB, a finer bonding lead portion is lined with a film. Therefore, it is disadvantageous in terms of flexibility compared to TAB without a film, and it is effective to prevent disconnection by using a material having better flexibility than before.

  On the other hand, in-vehicle electronic circuits have to cope with large currents due to the spread of hybridization and the development of fuel cell vehicles. Although it is estimated that the conductor thickness required for in-vehicle use will exceed 200 μm in the future, it is used as a flexible wiring board from the viewpoint of space saving. In order to apply such a thick copper foil to a flexible substrate, it is essential that the adhesive surface roughness of the copper foil is small, and rolled copper foil is also being considered as it cannot be handled by conventional electrolytic copper foil. . That is, in the case of the conventional electrolytic copper foil, the roughness of the adhesive surface with the base material increases as the thickness increases.

  Moreover, when using as a negative electrode electrical power collector for lithium ion batteries, it is preferable to use copper foil with a smooth surface. That is, when applying an active material on a copper foil, a copper foil with a smooth surface should be used as a current collector in order to apply the active material-containing slurry onto the copper foil with a uniform coating thickness. Is advantageous. And since the said negative electrode active material repeats expansion and contraction at the time of charging / discharging, the dimensional change of the copper foil as a current collection material is also large, and the phenomenon that copper foil expansion and contraction behavior cannot follow the expansion and contraction occurs. Therefore, the mechanical properties of the copper foil as a current collector are required to have a good balance between tensile strength and elongation rate in order to withstand repeated expansion and contraction behavior. Further, when a capacitor dielectric layer is formed on a copper foil by a sol-gel method, it is also advantageous to use a copper foil having a smooth surface.

  As described above, the market for electrolytic copper foil has been expanded from the use of printed wiring boards. As a result, it is clear that there is a need for an electrolytic copper foil that has a lower profile at a thickness of 450 μm or less and a good bendability compared to the low profile electrolytic copper foil for printed wiring boards that has been supplied to the market. It became.

  From the above background, as a result of earnest research, the present inventors have come up with a method for producing a low profile electrolytic copper foil having productivity comparable to that of conventional electrolytic copper foil production technology.

Manufacturing method of electrolytic copper foil according to the present invention: The manufacturing method of the electrolytic copper foil according to the present invention is to manufacture an electrolytic copper foil by stripping copper deposited on the cathode surface by an electrolytic method using a sulfuric acid-based copper electrolyte. The sulfuric acid-based copper electrolyte is 3-mercapto-1-propanesulfonic acid (hereinafter referred to as “MPS” in the present application) or bis (3-sulfopropyl) disulfide (hereinafter referred to as “SPS” in the present application). A diallyldimethylammonium chloride polymer (hereinafter referred to as “DDAC” in the present application ), which is a quaternary ammonium salt polymer having a cyclic structure, and chlorine. Is.

  In the manufacturing method of the electrolytic copper foil which concerns on this invention, it is preferable that the sum total density | concentration of MPS and / or SPS in the said sulfuric acid type copper electrolyte solution is 0.5 ppm-100 ppm.

  In the method for producing an electrolytic copper foil according to the present invention, the concentration of the quaternary ammonium salt polymer having a cyclic structure in the sulfuric acid-based copper electrolyte is preferably 1 ppm to 150 ppm.

  Furthermore, in the manufacturing method of the electrolytic copper foil which concerns on this invention, it is preferable that the chlorine concentration in the said sulfuric-type copper electrolyte solution is 5 ppm-120 ppm.

Electrolytic copper foil according to the present invention: The electrolytic copper foil according to the present invention is an electrolytic copper foil produced by the method for producing an electrolytic copper foil.

Surface-treated electrolytic copper foil according to the present invention: The surface-treated electrolytic copper foil according to the present invention is obtained by performing at least one of rust prevention treatment and silane coupling agent treatment on the surface of the above-described electrolytic copper foil.

  And it is preferable that the surface roughness (Rzjis) of an adhesive surface with the insulating-layer constituent material of the surface treatment electrolytic copper foil which concerns on this invention is 1.5 micrometers or less.

  Moreover, it is preferable to use a surface with the glossiness [Gs (60 °)] of 250 or more as an adhesive surface with the insulating layer constituting material of the surface-treated electrolytic copper foil according to the present invention.

  Furthermore, in the surface-treated electrolytic copper foil according to the present invention, it is also preferable to subject the surface-treated electrolytic copper foil to a bonding surface side with the insulating layer constituting material.

  And it is preferable to use the deposition surface of the said electrolytic copper foil for the adhesive surface with the insulating-layer constituent material of the surface treatment electrolytic copper foil which concerns on this invention.

Copper-clad laminate according to the present invention: The copper-clad laminate according to the present invention is obtained by bonding the surface-treated electrolytic copper foil and the insulating layer constituting material. And when the said insulating-layer constituent material which comprises the copper clad laminated board which concerns on this invention contains frame | skeleton material, it becomes a rigid copper clad laminated board. On the other hand, when the insulating layer constituting material constituting the copper clad laminate according to the present invention is a flexible material having flexibility, it becomes a flexible copper clad laminate.

Printed wiring board according to the present invention: By using the surface-treated electrolytic copper foil according to the present invention, a copper-clad laminate can be obtained, and by etching the copper-clad laminate, the printed wiring according to the present invention is obtained. A board is obtained. That is, a rigid printed wiring board can be obtained by using the above-mentioned rigid copper clad laminate. And a flexible printed wiring board is obtained by using the above-mentioned flexible copper clad laminated board.

The method for producing an electrolytic copper foil according to the present invention includes a DDAC polymer that is a quaternary ammonium salt polymer having a cyclic structure and at least one selected from MPS or SPS in the sulfuric acid copper electrolytic solution as an electrolytic solution, and chlorine. Is included. And the electrolytic copper foil obtained by this manufacturing method is provided with a more favorable low profile characteristic compared with the low profile electrolytic copper foil currently supplied to the market. As a result, in the method for producing an electrolytic copper foil according to the present invention, as the thickness of the produced electrolytic copper foil increases, the profile reduction becomes more prominent. This tendency is a property opposite to that of a conventional electrolytic copper foil that has a higher profile as the thickness increases.

  In addition, when this electrolytic copper foil is actually supplied to the market, various surface treatments are applied to prevent oxidation by the air atmosphere and to improve the adhesion to the base material. Supplied as copper foil. By using the electrolytic copper foil according to the present invention, as long as such a surface treatment is appropriately performed, even if the surface treatment is performed, the low profile electrolytic copper foil subjected to the surface treatment distributed in the market is used. Low profile exceeding can be achieved.

  Therefore, when the surface-treated electrolytic copper foil according to the present invention is used for a copper-clad laminate, the insulating layer located between the conductor layers composed of the surface-treated electrolytic copper foil according to the present invention has excellent thickness uniformity, and a thin insulating layer Even if the layer is used, the insulation reliability between layers is dramatically improved without causing a short circuit. In particular, if a uniform roughening treatment is performed, it is suitable for a copper clad laminate for high frequency.

  Furthermore, the printed wiring board obtained by etching the copper-clad laminate according to the present invention can reduce the profile of the surface-treated electrolytic copper foil according to the present invention used for the copper-clad laminate. Therefore, it is suitable for forming a fine pitch circuit.

[Mode of manufacturing electrolytic copper foil according to the present invention]
Before explaining the method for producing an electrolytic copper foil according to the present invention , a general method for producing an electrolytic copper foil will be described so that the explanation can be easily understood. The “electrolytic copper foil” according to the present invention is a state in which no surface treatment is performed, and is sometimes referred to as “untreated copper foil”, “deposited foil” or the like. In the present specification, this is simply referred to as “electrolytic copper foil”. In general, a continuous production method is adopted for the production of the electrolytic copper foil, and a drum-shaped rotating cathode and a lead-based anode or a dimensionally stable anode (DSA) arranged opposite to each other along the shape of the rotating cathode. ) And a sulfuric acid-based copper electrolytic solution is allowed to flow between them and copper is deposited on the surface of the rotating cathode using an electrolytic reaction, and the deposited copper is continuously peeled off from the rotating cathode as a foil. . The electrolytic copper foil obtained in this way is in the form of a roll wound up with a constant width. Therefore, the direction of rotation of the rotating cathode (the length direction of the web) is set to MD ( Machine Direction), the width direction perpendicular to MD is referred to as TD (Transverse Direction).

  The surface shape of the electrolytic copper foil that has been peeled off from the state in contact with the rotating cathode is a transfer of the shape of the polished rotating cathode surface, and this surface is called a “glossy surface” because it has gloss. I have done it. On the other hand, the surface shape on the side that was the precipitation side usually shows a mountain-shaped uneven shape because the crystal growth rate of precipitated copper differs for each crystal surface, and this side is referred to as a “deposition surface”. . In general, the roughness of the precipitation surface is greater than the roughness of the glossy surface, and when the electrolytic copper foil is subjected to surface treatment, the precipitation surface side is often subjected to a roughening treatment. It becomes a bonding surface with the insulating layer constituting material when the tension laminate is manufactured. Accordingly, the smaller the surface roughness of the bonded surface, the better the low profile surface-treated electrolytic copper foil.

  In this way, the electrolytic copper foil is subjected to surface treatments such as roughening treatment and oxidation prevention to reinforce the adhesive strength with the insulating layer constituent material by mechanical anchor effect, and the electrolytic copper foil that circulates in the market is Although it is completed, it may be used without roughening depending on the application. Subsequently, the manufacturing method of the electrolytic copper foil which concerns on this invention below is demonstrated.

The method for producing an electrolytic copper foil according to the present invention is a method for producing an electrolytic copper foil by stripping copper deposited on the cathode surface by an electrolytic method using a sulfuric acid-based copper electrolytic solution, the sulfuric acid-based copper electrolysis The liquid is characterized in that it contains at least one selected from MPS or SPS and a DDAC polymer which is a quaternary ammonium salt polymer having a cyclic structure and chlorine. By using the sulfuric acid-based copper electrolytic solution having this composition, the low profile electrolytic copper foil according to the present invention can be stably produced. Furthermore, by optimizing the electrolysis conditions, an electrolytic copper foil having a gloss [Gs (60 °)] exceeding 700 can be obtained. And the copper concentration in this sulfuric acid system copper electrolytic solution is 40 g / l-120 g / l, and a more preferred range is 50 g / l-80 g / l. The free sulfuric acid concentration in the sulfuric acid-based copper electrolyte is 60 g / l to 220 g / l, and a more preferable range is 80 g / l to 150 g / l.

The combined concentration of MPS and / or SPS in the sulfuric acid-based copper electrolyte according to the present invention is preferably 0.5 ppm to 100 ppm, more preferably 0.5 ppm to 50 ppm, and still more preferably 1 ppm to 30 ppm. When the concentration of MPS and / or SPS is less than 0.5 ppm, the deposited surface of the electrolytic copper foil becomes rough, making it difficult to obtain a low profile electrolytic copper foil. On the other hand, even if the concentration of MPS and / or SPS exceeds 100 ppm, the effect of smoothing the deposited surface of the obtained electrolytic copper foil is not improved, and only the cost of waste liquid treatment is increased. In addition, MPS and / or SPS referred to in the present invention are used in the meaning including each salt, and the stated value of concentration is sodium 3-mercapto-1-propanesulfonate as a sodium salt (the present application) (Hereinafter referred to as “MPS-Na”). And MPS takes an SPS structure by dimerizing in the sulfuric acid system copper electrolyte concerning the present invention. Therefore, the concentration of MPS or SPS means that 3-mercapto-1-propanesulfonic acid alone or salts such as MPS-Na, as well as those added as SPS and MPS as polymerized into SPS after being added to the electrolyte. The concentration also includes the modified product . The structural formula of MPS is shown as chemical formula 1, and the structural formula of SPS is shown as chemical formula 2 below. From the comparison of these structural formulas, it can be seen that the SPS structure is a dimer of MPS.

The quaternary ammonium salt polymer having a cyclic structure in the sulfuric acid-based copper electrolyte according to the present invention preferably has a concentration of 1 ppm to 150 ppm, more preferably 10 ppm to 120 ppm, and still more preferably 15 ppm to 40 ppm. is there. Here, various quaternary ammonium salt polymers having a cyclic structure can be used . However, considering the effect of forming a low profile precipitation surface, it is most preferable to use a DDAC polymer. DDAC forms a cyclic structure when taking a polymer structure, and a part of the cyclic structure is composed of a quaternary ammonium nitrogen atom. The DDAC polymer is considered to be a compound in which the cyclic structure is a 4-membered ring to a 7-membered ring or a mixture thereof, and among these polymers, a compound having a 5-membered ring structure is representative. The following is shown as chemical formula 3. As can be clearly understood from the chemical formula 3, the DDAC polymer has a polymer structure of a dimer or higher .

And it is preferable that the density | concentration in this sulfuric acid type | system | group copper electrolyte solution of this DDAC polymer is 1 ppm-150 ppm, More preferably, it is 10 ppm-120 ppm, More preferably, it is 15 ppm-40 ppm. When the concentration of the DDAC polymer in the sulfuric acid-based copper electrolyte is less than 1 ppm, the deposition surface of electrodeposited copper becomes rough no matter how high the MPS or SPS concentration is, and a low profile electrolytic copper foil can be obtained. It becomes difficult. On the other hand, when the concentration of the DDAC polymer in the sulfuric acid-based copper electrolyte exceeds 150 ppm , the copper deposition state becomes unstable, and it becomes difficult to obtain a low profile electrolytic copper foil.

Furthermore, the chlorine concentration in the sulfuric acid-based copper electrolyte is preferably 5 ppm to 120 ppm, more preferably 10 ppm to 60 ppm. When the chlorine concentration is less than 5 ppm, the deposited surface of the electrolytic copper foil becomes rough and the low profile cannot be maintained. On the other hand, even if the chlorine concentration exceeds 120 ppm , the deposited surface of the electrolytic copper foil becomes rough, the electrodeposition state is not stable, and a low profile deposited surface cannot be formed.

As described above, the component balance of MPS and / or SPS, DDAC polymer and chlorine in the sulfuric acid-based copper electrolytic solution is the most important, and if these quantitative balances deviate from the above range, as a result, electrolytic copper The deposited surface of the foil becomes rough and the low profile cannot be maintained.

And when manufacturing an electrolytic copper foil using the said sulfuric acid system copper electrolyte solution, it electrolyzes using the cathode and insoluble anode whose surface roughness was adjusted to the predetermined range . At this time the liquid temperature is 20 ° C. to 60 ° C., more preferably between 40 ° C. to 55 ° C., a current density of ^{15A / dm 2 ~90A / dm 2} , more preferably to ^50A / dm ^{2 ~70A} / dm 2 preferable.

And in the case of the manufacturing method of the electrolytic copper foil which concerns on this invention, in order to acquire the characteristic calculated | required by the said electrolytic copper foil stably, the cathode surface state at the time of manufacturing should also be managed. Referring to JIS C 6515, which is a standard for electrolytic copper foil for printed wiring boards, the surface roughness (Rzjis) of the glossy surface required for the electrolytic copper foil is specified to be a maximum of 2.4 μm. When a rotating cathode drum made of titanium (Ti) is used as a cathode for producing this electrolytic copper foil, the appearance change and the metal phase change due to surface oxidation occur during continuous use. Therefore, mechanical work such as periodic surface polishing and polishing or cutting depending on the state is required. Such mechanical machining of the cathode surface is carried out while rotating the cathode, so that a streak pattern is inevitably generated in the circumferential direction. For this reason, it is difficult to maintain the surface roughness (Rzjis) of the glossy surface in a small state , and the standard value is based on the premise that there is no problem in terms of cost and printed wiring board production. Is allowed.

In the case of the conventional electrolytic copper foil, the precipitation surface roughness tends to increase as the thickness increases. As another factor, when a cathode drum having a surface roughness higher than the upper limit level of the standard value is used, the roughness of the deposited surface of the obtained electrolytic copper foil is affected by the surface shape of the cathode. There is a tendency to grow. On the other hand, when the above copper sulfate electrolyte is used, it becomes difficult to be influenced by the shape of the cathode surface in the process of growing the film thickness while filling the unevenness of the cathode surface, and a flat deposition surface can be formed. Become. In other words, compared to the conventional copper electrolyte used for the production of electrolytic copper foil, the production of an electrolytic copper foil using the above-mentioned copper sulfate-based electrolytic solution is less affected by the shape of the cathode surface and the use of a cathode with a rough surface Is also possible.

For example, in the case of producing an electrolytic copper foil having a thickness of less than 20 μm, when the precipitation surface roughness (Rzjis) of the obtained electrolytic copper foil is less than 1.0 μm, the surface of the glossy surface of the electrolytic copper foil Roughness (Rzjis) is less than 2.0 μm, and using a cathode in a surface state such that glossiness [Gs (60 °)] is 70 or more, the mechanical properties and surface in the TD direction and MD direction are used. This is preferable from the viewpoint of reducing the difference in characteristics. More preferably, a cathode having a surface state such that the surface roughness (Rzjis) of the glossy surface of the electrolytic copper foil is less than 1.7 μm and the glossiness [Gs (60 °)] is 100 or more is used. Is preferable from the same viewpoint.

[Form of electrolytic copper foil according to the present invention]
The electrolytic copper foil which concerns on this invention was manufactured by the manufacturing method of the said electrolytic copper foil. Various characteristics of the electrolytic copper foil obtained by this manufacturing method will be described below.

  The electrolytic copper foil according to the present invention has the characteristics that the surface roughness (Rzjis) on the deposition surface side is less than 1.0 μm and the glossiness [Gs (60 °)] is 400 or more. More preferably, the surface roughness (Rzjis) is less than 0.6 μm, and the glossiness [Gs (60 °)] is 600 or more. First, the glossiness will be described. Here, the glossiness of [Gs (60 °)] is obtained by measuring the intensity of light bounced at a reflection angle of 60 ° by irradiating the surface of the electrolytic copper foil with measurement light at an incident angle of 60 °. The incident angle referred to here is 0 ° in the direction perpendicular to the light irradiation surface. According to JIS Z 8741-1997, five specular gloss measurement methods having different incident angles are described, and an optimal incident angle should be selected according to the gloss of the sample. In particular, it is said that by setting the incident angle to 60 °, it is possible to measure a wide range of samples from low gloss samples to high gloss samples. Therefore, 60 ° is mainly used for the glossiness measurement of the electrolytic copper foil according to the present invention.

  In general, the surface roughness Rzjis has been used as a parameter for evaluating the smoothness of the deposited surface of the electrolytic copper foil. However, with Rzjis alone, only the unevenness information in the height direction can be obtained, and information such as the unevenness period and waviness cannot be obtained. Since the glossiness is a parameter reflecting both information, it can be comprehensively determined by using Rzjis in combination with various parameters such as surface roughness period, waviness, and uniformity within the surface. .

  In the case of the electrolytic copper foil according to the present invention, the condition that the surface roughness (Rzjis) on the deposition surface side is less than 1.0 μm and the glossiness [Gs (60 °)] of the deposition surface is 400 or more. Meet. That is, there has been no electrolytic copper foil that can guarantee quality in such a range and can be supplied to the market. And by using the manufacturing method mentioned later appropriately, it is possible to provide an electrolytic copper foil having a precipitation surface with a surface roughness (Rzjis) of less than 0.6 μm and a glossiness [Gs (60 °)] of 700 or more. Become. Here, the upper limit value of the glossiness is not defined, but it is determined empirically that the upper limit is about 780 in [Gs (60 °)]. In addition, the glossiness in this invention was measured based on JIS Z8741-1997 which is a measuring method of glossiness using the Nippon Denshoku Industries Co., Ltd. gloss meter VG-2000 type.

  The thickness of the electrolytic copper foil referred to here is not limited. This is because, as the thickness increases, the roughness of the precipitation surface decreases, and the glossiness tends to increase. If the upper limit is determined, it is intended for an electrolytic copper foil having a thickness of 450 μm or less, which is the limit that can be profitable even if the electrolytic copper foil is manufactured industrially.

  Further, the lower limit value of the surface roughness (Rzjis) on the precipitation surface side is not limited here. Although it depends on the sensitivity of the measuring instrument, the lower limit of the surface roughness is empirically about 0.1 μm. However, in actual measurement, variation is observed, and the lower limit of the measurement value that can be guaranteed is considered to be about 0.2 μm.

  In the electrolytic copper foil according to the present invention, the glossiness [Gs (60 °)] on the deposition surface side is divided into TD glossiness measured in the width direction and MD glossiness measured in the flow direction. When this ratio ([TD glossiness] / [MD glossiness]) is taken, it is in the range of 0.9 to 1.1. That is, the difference between the width direction and the flow direction is very small.

  That is, it is a general idea that the electrolytic copper foil has different mechanical characteristics in the width direction (TD) and the flow direction (MD) due to the influence of polishing stripes on the surface of the rotating drum as the cathode. However, the electrolytic copper foil according to the present invention has a more uniform and smooth deposition surface side surface regardless of the thickness, and the glossiness [Gs (60 °)] as its appearance is [TD glossiness] / [MD The value of [Glossiness] is 0.9 to 1.1, the change width is as small as 10% or less, and the variation in the surface shape between the TD direction and the MD direction of the electrolytic copper foil according to the present invention is extremely small. is doing.

  And further speaking, the fact that there is no difference in appearance between the TD direction and the MD direction means that uniform electrolysis has been achieved and that the crystal structure is uniform. That is, it means that mechanical property differences such as tensile strength and elongation in the TD direction and MD direction are also reduced. Thus, it is preferable that the difference in mechanical characteristics between the TD direction and the MD direction is small because the influence on the dimensional change rate of the substrate and the linearity of the circuit due to the directionality of the copper foil when manufacturing the printed wiring board is reduced. . Incidentally, in the case of a rolled copper foil that can be said to be a representative copper foil with a smooth surface, it is widely known that the mechanical properties in the TD direction and the MD direction differ due to the processing method. As a result, the rate of dimensional change is large in the film carrier tape market, thin rigid printed wiring boards, and the like, which are the applications envisaged by the present invention, and the evaluation of being unsuitable for fine pattern applications is almost firmly established.

  Further, by using [Gs (20 °)] and [Gs (60 °)] as the glossiness, the difference from the conventional low profile electrolytic copper foil can be grasped more clearly. Specifically, as for the electrolytic copper foil which concerns on this invention, the said precipitation surface side can be provided with the relationship of glossiness [Gs (20 degrees)]> glossiness [Gs (60 degrees)]. If it is the same material, it is expected that it is sufficient to select one incident angle and evaluate the glossiness, but even with the same material, the reflectivity varies depending on the incident angle, so if the incident angle changes The spatial distribution of the reflected light changes according to the surface irregularities of the surface to be measured, resulting in a difference in glossiness. Based on this fact, as a result of studies by the present inventors, it has been found from experience that there is the following tendency. That is, in the case of an electrolytic copper foil having high gloss and low surface roughness, there is a relationship of gloss [Gs (20 °)]> gloss [Gs (60 °)]> gloss [Gs (85 °)]. In the case of an electrolytic copper foil with low gloss and low surface roughness, the relationship of gloss [Gs (60 °)]> gloss [Gs (20 °)]> gloss [Gs (85 °)] Is established. Further, in the case of an electrolytic copper foil having a dull and low surface roughness, there is a relationship of gloss [Gs (85 °)]> gloss [Gs (60 °)]> gloss [Gs (20 °)]. To establish. As can be seen from the above, it is meaningful to evaluate the smoothness based on the relationship with the measured glossiness at different incident angles in addition to the absolute value of the glossiness at a constant incident angle.

  And in the case of the electrolytic copper foil which concerns on this invention, the surface state of the glossy surface is also important. The glossy surface is required to have a level of surface roughness (Rzjis) and glossiness [Gs (60 °)] close to the deposited surface of the electrolytic copper foil according to the present invention. That is, in the electrolytic copper foil according to the present invention, the glossy surface side preferably has a surface roughness (Rzjis) of less than 2.0 μm and a glossiness [Gs (60 °)] of 70 or more. . More preferably, the surface roughness (Rzjis) is less than 1.7 μm and the glossiness [Gs (60 °)] is 100 or more. Although the upper limit of the glossiness [Gs (60 °)] of the glossy surface is not specified, it is empirically about 500. That is, in order to obtain the surface state of the precipitation surface described so far, it is preferable to form the surface state described here on the glossy surface. If this condition is not satisfied, a difference in the surface state in the TD direction and the MD direction tends to occur, and mechanical characteristics such as tensile strength and elongation in the TD direction and MD direction also tend to occur. The surface state of the glossy surface is a transfer of the surface state of the cathode, which is the electrodeposited surface, and is determined by the surface state of the cathode. Therefore, when manufacturing a thin electrolytic copper foil, the cathode surface is required to have a surface roughness (Rzjis) of less than 2.0 μm.

As the mechanical properties of the electrolytic copper foil according to the present invention, the tensile strength in a normal state is 33 kgf / mm ² or more, and the elongation is 5% or more. And after heating (180 degreeC x 60 minutes, air atmosphere), it is preferable that tensile strength is 30 kgf / mm < ² > or more and elongation rate is 8% or more.

And in this invention, by optimizing manufacturing conditions, normal tensile strength is 38 kgf / mm ² or more, and tensile strength after heating (180 ° C. × 60 minutes, air atmosphere) is 33 kgf / mm ² or more. It can be said to have more excellent mechanical properties. Therefore, this good mechanical property not only can withstand bending use of flexible printed wiring boards, but also for current collector applications that constitute negative electrodes such as lithium ion secondary batteries that undergo expansion and contraction behavior. Is also suitable.

[Form of surface-treated electrolytic copper foil according to the present invention]
The surface-treated electrolytic copper foil according to the present invention provides a surface-treated electrolytic copper foil obtained by performing at least one of rust prevention treatment and silane coupling agent treatment on the surface of the above-described electrolytic copper foil. This antirust treatment layer is for preventing the surface of the electrolytic copper foil from being oxidatively corroded so as not to hinder the manufacturing process of the copper clad laminate and the printed wiring board. And it is recommended that it is the structure which improves if possible, without inhibiting adhesiveness with an insulating-layer constituent material. The method used for the rust prevention treatment is suitable for the intended use even if either organic rust prevention using benzotriazole, imidazole, etc., or inorganic rust prevention using zinc, chromate, zinc alloy, etc., or a combination of both is used. If so, there is no problem.

  And a silane coupling agent process is a process for improving the adhesiveness with an insulating-layer constituent material chemically after a rust prevention process is complete | finished.

Next, a method for forming a rust prevention treatment layer will be described. In the case of organic rust prevention, it becomes possible to form a solution of an organic rust prevention agent by employing techniques such as dip coating, showering coating, and electrodeposition. In the case of inorganic rust prevention, a method of electrolytically depositing a rust-preventive element on the surface of the electrolytic copper foil, other so-called substitution deposition methods, and the like can be used. For example, when the zinc rust prevention treatment is performed, a zinc pyrophosphate plating bath, a zinc cyanide plating bath, a zinc sulfate plating bath, or the like can be used. For example, in the case of a zinc pyrophosphate plating bath, the concentrations are 5 g / l to 30 g / l zinc, 50 g / l to 500 g / l potassium pyrophosphate, liquid temperature 20 ° C. to 50 ° C., pH 9 to 12, and current density 0.3A. / Dm ^{2 to} 10 A / dm ² .

  And the silane coupling agent used for the said silane coupling agent process does not require limitation in particular, Considering properties, such as an insulating-layer constituent material to be used, and the plating solution used at a printed wiring board manufacturing process, it is an epoxy type. A silane coupling agent, an amino silane coupling agent, a mercapto silane coupling agent, and the like can be arbitrarily selected and used. And a silane coupling agent process can employ | adopt methods, such as dip coating, showering application | coating, and an electrodeposition method, for the solution of a silane coupling agent.

  More specifically, vinyl trimethoxy silane, vinyl phenyl trimethoxy lane, γ-methacryloxypropyl trimethoxy silane, γ-glycol are mainly used for the same coupling agent as used for prepreg glass cloth for printed wiring boards. Sidoxypropyltrimethoxysilane, 4-glycidylbutyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-β (aminoethyl) γ-aminopropyltrimethoxysilane, N-3- (4- (3-aminopropoxy) ) Putoxy) propyl-3-aminopropyltrimethoxysilane, imidazole silane, triazine silane, γ-mercaptopropyltrimethoxysilane and the like can be used.

  And it is preferable that the surface roughness (Rzjis) of the adhesive surface with the insulating-layer constituent material of the said surface treatment electrolytic copper foil is a low profile of 1.5 micrometers or less. By adjusting the surface roughness within this range, a surface-treated copper foil suitable for fine pitch circuit formation is obtained.

  Moreover, it is also preferable that the glossiness [Gs (60 °)] of the adhesion surface between the surface-treated electrolytic copper foil and the insulating layer constituting material is 250 or more. The surface treatment forms a rust-preventive coating or a silane coupling agent coating, so even if the surface roughness change is not detected, the light reflectance may vary in the comparison before and after the surface treatment. Conceivable. Therefore, although the absolute value of the glossiness may fluctuate after the surface treatment, if the glossiness [Gs (60 °)] obtained on the adhesive surface of the surface-treated electrolytic copper foil is maintained at 250 or more, the surface-treated film Can be determined to be formed with an appropriate thickness.

  It is also preferable that the surface of the surface-treated electrolytic copper foil that has been subjected to a roughening treatment is bonded to the insulating layer constituting material. For the roughening treatment, a publicly-known technique can be applied, and it is sufficient to perform the minimum necessary roughening treatment in combination with the rust prevention technique. However, in the formation of fine pitch wiring that is less than 25 μm pitch in which the surface-treated electrolytic copper foil according to the present invention is preferably used, the rough etching treatment is not performed, and the required overetching time setting accuracy is achieved. It is preferable for raising.

  And as a method of performing a roughening process, either a fine metal particle is made to adhere and form on the surface of electrolytic copper foil, or a roughened surface is formed by the etching method, and any method is employ | adopted. Here, as the former method of depositing and forming fine metal particles, a method of depositing and forming copper fine particles on the surface will be exemplified. This roughening treatment step includes a step of depositing and adhering fine copper particles on the surface of the electrolytic copper foil, and a covering plating step for preventing the fine copper particles from falling off.

In the step of depositing and adhering fine copper particles on the surface of the electrolytic copper foil, the condition of burnt plating is adopted as the electrolysis condition. Therefore, the solution concentration used in the step of depositing and adhering fine copper particles is generally low so that the burn plating conditions can be easily created. The burn plating conditions are not particularly limited, and are determined in consideration of the characteristics of the production line. For example, if a copper sulfate-based solution is used, the concentration of copper is 5 to 20 g / l, free sulfuric acid is 50 to 200 g / l, and other additives as necessary (α-naphthoquinoline, dextrin, glue, thiourea, etc.), For example, the liquid temperature is 15 to 40 ° C. and the current density is 10 to 50 A / dm ² .

The covering plating process for preventing the fine copper grains from falling off is a process for uniformly depositing copper so as to cover the fine copper grains under smooth plating conditions. Therefore, here, a copper electrolyte similar to that used in the above-described electrolytic copper foil manufacturing process can be used as a source of copper ions. The smooth plating conditions are not particularly limited and are determined in consideration of the characteristics of the production line. For example, if a copper sulfate-based solution is used, the concentration is 50 to 80 g / l copper, free sulfuric acid 50 to 150 g / l, liquid temperature 40 to 50 ° C., and current density 10 to 50 A / dm ^2. is there.

  And it is said that it is preferable that the adhesion surface with the insulating-layer constituent material of the said surface treatment electrolytic copper foil is a deposition surface side. As described above, it is difficult to eliminate the difference between the TD direction and the MD direction on the glossy surface side because the surface shape of the cathode drum is a transferred shape. For this reason, in order to minimize the variation in the linearity of the wiring end surface that occurs when the shape of the bonding surface is TD / MD and has directionality, it is preferable that the deposition surface side be the bonding surface.

[Form of copper clad laminate according to the present invention]
The present invention provides a copper clad laminate obtained by laminating the surface-treated electrolytic copper foil with an insulating layer constituting material. As for the production method of these copper clad laminates, conventional roll laminating method and casting method can be used as long as they are flexible copper clad laminates, and hot press method and continuous laminating are used for rigid copper clad laminates. It is possible to manufacture using a method. The flexible copper-clad laminate and the rigid copper-clad laminate referred to in the present invention are concepts including all of a single-sided copper-clad laminate, a double-sided copper-clad laminate, and a multilayer copper-clad laminate. Here, in the case of a multilayer copper-clad laminate, the surface-treated copper foil according to the present invention is used for the outer layer, and the inner layer includes an inner layer core material having an inner layer circuit. In the explanation of the following copper-clad laminate, these are not explained separately. This is because it becomes a duplicate.

  The present invention provides a rigid copper clad laminate in which the insulating layer constituting material contains a skeleton material. Most of the skeletal materials used in conventional rigid copper clad laminates are glass woven fabrics or glass nonwoven fabrics, and the roughness of the copper foil bonding surface affects the interlayer insulation at a level exceeding 10 μm. In the following, it has been reported that the migration resistance due to the direct contact between the glass fiber, which is a skeleton material, and the circuit can be a problem. And it has been said that there is no need to make it a problem if the level is 5 μm. However, recently, for example, BGA and CSP, which are package substrates on which electronic components are directly mounted, require a fine pattern of a level that has never existed before, and the surface is flat, for example, aramid fibers thinner than glass fibers are used as a skeleton material. We are trying to make it. When a component with a high clock frequency is mounted, the signal transmission characteristics in the high frequency range cannot be satisfied particularly when the linearity and cross-sectional shape of the circuit are far from the ideal state. Therefore, the copper-clad laminate according to the present invention is suitable not only for fine patterns but also for manufacturing printed wiring boards having a high-frequency signal transmission circuit.

  The present invention also provides a flexible copper clad laminate in which the insulating layer constituting material is constituted by a flexible material having flexibility. The flexible copper-clad laminate has been divided into its use by the flexibility and light weight of the above-mentioned rigid copper-clad laminate, and the insulating layer constituent material is for weight reduction and high flexibility. Thinning is attempted. At the same time, the conductor layer is also required to be thin, and electrolytic copper foil is the main material. And, in order to ensure insulation reliability in thin films, especially for multilayer flexible substrates, a low profile of 1/10 or less of the insulating layer thickness is required for the adhesive surface. Rzjis = about 5 μm was the upper limit of use. However, the flexible copper clad laminate using the electrolytic copper foil of the present invention can ensure insulation reliability even if the film thickness is further reduced. And it is excellent in the flexibility compared with the flexible copper clad laminated board using the conventional low profile electrolytic copper foil, It is a copper clad laminated board which improved the reliability also in this point.

  Here, the manufacturing method of a rigid copper clad laminated board and a flexible copper clad laminated board is illustrated concretely. When manufacturing rigid copper clad laminates or flexible copper clad laminates, surface treatment electrolytic copper foil according to the present invention, rigid insulation layer forming material such as FR-4 class prepreg, or flexible insulation layer such as polyimide resin film Using the forming material and the end plate, a desired lay-up state is formed and press-molded between 170 ° C. and 200 ° C. hot.

  On the other hand, in the case of a flexible copper-clad laminate, it is possible to adopt the roll laminating method or the casting method as described above. This roll laminating method is a method in which a roll of surface-treated copper foil according to the present invention and a resin film roll such as a polyimide resin film or a PET film are thermocompression-bonded by the pressure of a heating roll in the Roll to Roll method. is there. And the casting method means that the surface-treated copper foil is formed by forming a resin composition film that is converted into a polyimide resin by heating such as polyamic acid on the surface of the surface-treated copper foil according to the present invention, and causing a condensation reaction by heating. A polyimide resin film is directly formed on the surface of the film.

[Form of printed wiring board according to the present invention]
And this invention provides the rigid printed wiring board characterized by being obtained using the said rigid copper clad laminated board. As described above, not only the subtractive method but also the pattern plating / flash etching method can be used for the production of the printed wiring board using the copper-clad laminate using the electrolytic copper foil having a smooth adhesive surface according to the present invention. In either case, since the setting of the overetching time can be shortened, the end face of the obtained circuit is more linear and the cross section is closer to a rectangle. Therefore, it is excellent in insulation reliability between circuits with fine patterns, and at the same time has excellent signal transmission characteristics in the high frequency region that flows near the circuit surface due to the skin effect, and it is also difficult to generate noise such as crosstalk. It is a printed wiring board with excellent reliability.

  Moreover, this invention provides the flexible printed wiring board characterized by using the said flexible copper clad laminated board. For the production of the printed wiring board, the pattern plating / flash etching method as well as the subtractive method as well as the above-mentioned rigid printed wiring board can be used. In both cases, the setting of the overetching time can be shortened. The end face of the resulting circuit is more linear and the cross section is more rectangular. Therefore, it is a highly reliable printed wiring board that has excellent signal transmission characteristics in the high frequency range and that does not easily generate noise such as crosstalk. At the same time, it has excellent insulation reliability and flexibility. The film carrier that can be directly mounted can demonstrate its superiority.

  Here, an example of a general processing method in the case of processing into a printed wiring board using either the above-mentioned rigid copper-clad laminate or flexible copper-clad laminate (hereinafter simply referred to as “copper-clad laminate”). , Just in case. First, an etching resist layer is formed on the surface of the copper clad laminate, and the etching circuit pattern is exposed and developed to form an etching resist pattern. At this time, a photosensitive resin such as a dry film or a liquid resist is used for the etching resist layer. In addition, UV exposure is generally used for exposure, and an etching resist pattern forming method based on a conventional method can be employed.

  Then, the electrolytic copper foil is etched into a circuit shape using a copper etchant, and the etching resist is removed to form a desired circuit shape on the surface of the rigid base material or the flexible base material. Regarding the etching solution at this time, all copper etching solutions such as an acidic copper etching solution and an alkaline copper etching solution can be used.

  As described above, the copper-clad laminate referred to in the present invention is described as a concept including all of a single-sided copper-clad laminate, a double-sided copper-clad laminate, and a multilayer copper-clad laminate having an internal circuit inside. Therefore, in the case of double-sided copper-clad laminates and multilayer copper-clad laminates, it may be necessary to ensure electrical continuity between the layers. In such a case, shape formation of through holes, via holes, etc. by a regular method is required. After that, a conduction plating process for obtaining interlayer conduction is performed. In general, this conductive plating treatment is an activation treatment using a palladium catalyst to perform a copper electroless plating, and then a film thickness is grown by electrolytic copper plating.

  When the copper etching is completed, the substrate is sufficiently washed with water, dried, and subjected to other rust-proofing treatment as necessary to obtain a rigid printed wiring board or a flexible printed wiring board.

  In consideration of the fact that the surface shape of the cathode is not affected in the examples and the comparative examples, a titanium plate electrode whose surface was polished with No. 2000 polishing paper and the surface roughness was adjusted to 0.85 μm with Rzjis was used. .

[First Implementation Group]
In the first working group, Examples 1 to 8 were performed. In Examples 1 to 8, the sulfuric acid-based copper electrolyte was a copper sulfate solution having a copper concentration of 80 g / l, a free sulfuric acid concentration of 140 g / l, and the MPS concentration and DDAC polymer (Table 1). A solution adjusted to a concentration and a chlorine concentration was used. In Example 9, SPS, which is a dimer of MPS, was used as an alternative to MPS.

The electrolytic copper foil was prepared by using DSA as an anode and electrolyzing at a liquid temperature of 50 ° C. and a current density of 60 A / dm ² to obtain nine types of electrolytic copper foils having a thickness of 12 μm and 210 μm. The mechanical properties of the copper foil were evaluated by limiting to the 12 μm electrolytic copper foil. The results are shown in Table 2.

Next, the both sides of the electrolytic copper foil were subjected to rust prevention treatment, and here, inorganic rust prevention under the conditions described below was adopted. Using a zinc sulfate bath, a free sulfuric acid concentration of 70 g / l, a zinc concentration of 20 g / l, a liquid temperature of 40 ° C., a current density of 15 A / dm ² were applied, and a zinc rust prevention treatment was performed.

Further, in the case of this example, a chromate layer was formed by electrolysis on the zinc rust preventive layer. The electrolysis conditions at this time were chromic acid concentration 5.0 g / l, pH 11.5, liquid temperature 35 ° C., current density 8 A / dm ² , and electrolysis time 5 seconds.

  When the rust prevention treatment was completed as described above, the silane coupling agent was adsorbed on the rust prevention treatment layer on the deposition surface side immediately in the silane coupling agent treatment tank after washing with water. The solution composition at this time was such that the concentration of γ-glycidoxypropyltrimethoxysilane was 5 g / l using pure water as a solvent. The solution was adsorbed by spraying with a shower ring.

  When the silane coupling agent treatment was completed, water was finally diffused by an electric heater to obtain nine types of surface-treated electrolytic copper foil. In addition, according to the crystal structure analysis of the obtained electrolytic copper foil, the average crystal particle diameter is the average crystal particle diameter of the electrolytic copper foil having a low profile due to the fine crystallization used in the conventional film carrier tape. The presence of twins was also confirmed. Surface roughness (Rzjis) and glossiness [Gs (20 °)], [Gs (60 °)] and [Gs (85 °)] of the deposited surface of the electrolytic copper foil obtained from the above, and surface-treated electrolytic copper Table 3 shows the surface roughness (Rzjis) and glossiness [Gs (60 °)] of the deposited surface of the foil.

[Second implementation group]
Here, Examples 10 to 14 were used, and as the sulfuric acid-based copper electrolyte, the copper concentration was 80 g / l, the free sulfuric acid concentration was 140 g / l, and the SPS concentrations shown in Table 4, DDAC polymer (Unisense manufactured by Senka Co., Ltd.) FPA100L) A solution adjusted to a concentration and a chlorine concentration was used.

The electrolytic copper foil was prepared by using DSA as an anode, electrolyzing at a liquid temperature of 50 ° C., and a current density of 60 A / dm ^{2. In} Example 10, two types of electrolytic copper foils having a thickness of 12 μm and 70 μm were used in Examples 11 to 11. In Example 14, four types of electrolytic copper foils having a thickness of 12 μm were obtained.

And the normal state of 12 μm and 70 μm electrolytic copper foil obtained in Example 10 and 180 ° C. × 60 min. Table 5 shows the tensile strength and elongation after heating. The normal tensile strength of the 12 μm electrolytic copper foil was 35.5 kgf / mm ² , the elongation was 11.5%, and 180 ° C. × 60 min. Good mechanical properties such as a tensile strength after heating of 33.2 kgf / mm ² and an elongation of 11.2% are at a level that can sufficiently withstand bending use of a flexible printed wiring board.

  When the folding resistance of the 12 μm electrolytic copper foil alone is evaluated by the MIT method, it can withstand a bending test of 1200 to 1350 times in a normal state and 800 to 900 times even after heating. The folding resistance test by the MIT method uses a film folding fatigue tester with tank (product number: 549) manufactured by Toyo Seiki Seisakusho as an MIT folding apparatus, with a bending radius of 0.8 mm, a load of 0.5 kgf, and a sample size of 15 mm. * Implemented at 150 mm. This value is about 600 times in a normal state when a general-purpose electrolytic copper foil that has been used for flexible printed wiring boards is evaluated under the same conditions, and about 500 times after heating. Thus, the folding endurance is approximately doubled. It can be inferred that this difference is due to the fact that the surface is smooth, so that cracks that trigger breakage are less likely to occur.

  Then, the electrolytic copper foil obtained above was immersed in a dilute sulfuric acid solution having a concentration of 150 g / l and a liquid temperature of 30 ° C. for 30 seconds to remove deposits and surface oxide film, and washed with water. In the 12 μm electrolytic copper foil and the 70 μm electrolytic copper foil obtained in Example 10, a total of four types of surface-treated electrolytic copper foil subjected to roughening treatment and two types of surface-treated electrolytic copper foil not subjected to roughening treatment were used. Created.

Among the above, the 12 μm electrolytic copper foil and the 70 μm electrolytic copper foil to be subjected to the roughening treatment are subjected to a fine copper particle on the deposition surface as a step of forming fine copper grains on the deposition surface of the electrolytic copper foil when the pickling treatment is completed. A step of depositing and adhering the grains and a covering plating step for preventing the fine copper grains from falling off were performed. In the former process of depositing fine copper particles, a copper sulfate-based solution, which has a copper concentration of 15 g / l, a free sulfuric acid concentration of 100 g / l, a liquid temperature of 25 ° C., and a current density of 30 A / dm ² for 5 seconds. Electrolyzed.

When fine copper grains were adhered and formed on the deposition surface, copper was uniformly deposited so as to cover the fine copper grains under smooth plating conditions as a covering plating process for preventing the fine copper grains from falling off. Here, the smooth plating conditions were a copper sulfate solution, a copper concentration of 60 g / l, a free sulfuric acid concentration of 100 g / l, a liquid temperature of 45 ° C., and a current density of 45 A / dm ² , and electrolysis was performed for 5 seconds.

In this example, both surfaces of all the obtained electrolytic copper foils were subjected to rust prevention treatment. Here, inorganic rust prevention under the conditions described below was adopted. Using a zinc sulfate bath, a free sulfuric acid concentration of 70 g / l, a zinc concentration of 20 g / l, a liquid temperature of 40 ° C., a current density of 15 A / dm ² were applied, and a zinc rust prevention treatment was performed.

A chromate layer was further formed on the zinc rust preventive layer by electrolysis. The electrolysis conditions at this time were chromic acid concentration 5.0 g / l, pH 11.5, liquid temperature 35 ° C., current density 8 A / dm ² , and electrolysis time 5 seconds.

  When the rust prevention treatment was completed as described above, the silane coupling agent was adsorbed on the rust prevention treatment layer on the deposition surface side immediately in the silane coupling agent treatment tank after washing with water. The solution composition at this time was such that the concentration of γ-glycidoxypropyltrimethoxysilane was 5 g / l using pure water as a solvent. The solution was adsorbed by spraying with a shower ring. When the silane coupling agent treatment was completed, water was finally diffused by an electric heater to obtain six types of surface-treated electrolytic copper foil including one type of roughened foil.

  Surface roughness (Rzjis) and glossiness [Gs (60 °)] on the glossy surface side of the electrolytic copper foils obtained from Examples 10 to 14 above, surface roughness (Rzjis) and glossiness on the deposition surface side [Gs (20 °)], [Gs (60 °)] and [Gs (85 °)], and surface roughness (Rzjis) and glossiness [Gs of the precipitation surface of the surface-treated foil obtained in Example 10 (60 °)], the surface roughness (Rzjis) of the roughened surface of the roughened foil is shown in Table 6.

Comparative example

[Comparative Example 1]
This comparative example is a trace experiment of Example 1 described in Patent Document 2. As a sulfuric acid-based copper electrolyte, a basic solution was prepared by dissolving copper sulfate (reagent) and sulfuric acid (reagent) in pure water to obtain a copper sulfate (pentahydrate equivalent) concentration of 280 g / l and a free sulfuric acid concentration of 90 g / l. . A copolymer of diallyldialkylammonium salt and sulfur dioxide (manufactured by Nitto Boseki Co., Ltd., trade name PAS-A-5, weight average molecular weight 4000) concentration 4 ppm, polyethylene glycol (average molecular weight 1000) concentration 10 ppm, MPS-Na The sulfuric acid acidic copper plating solution was adjusted to a concentration of 1 ppm and further adjusted to a chlorine concentration of 20 ppm using sodium chloride.

Then, a lead plate was used for the anode, and the above electrolytic solution was electrolyzed at a liquid temperature of 40 ° C. and a current density of 50 A / dm ² to obtain electrolytic copper foils having thicknesses of 12 μm and 210 μm. The mechanical properties of this electrolytic copper foil are shown in Table 2, and the surface roughness (Rzjis) and glossiness [Gs (60 °)] of the deposition surface are shown in Table 3 together with examples.

[Comparative Example 2]
In this comparative example, as a sulfuric acid-based copper electrolyte, a solution having a copper concentration of 90 g / l and a free sulfuric acid concentration of 110 g / l was passed through an activated carbon filter for cleaning treatment. Subsequently, an MPS-Na concentration of 1 ppm, a hydroxypolysaccharide concentration of 5 ppm as a high molecular polysaccharide, a low molecular weight glue (number average molecular weight 1560) concentration of 4 ppm, and a chlorine concentration of 30 ppm were added to this solution. Was prepared. The copper electrolyte thus prepared was used, and a DSA electrode was used as the anode, and electrolysis was performed at a liquid temperature of 58 ° C. and a current density of 50 A / dm ² to obtain electrolytic copper foils having thicknesses of 12 μm and 210 μm. Table 2 shows the mechanical properties of this electrolytic copper foil, and Table 3 shows the surface roughness (Rzjis), glossiness, etc. of the deposited surface together with examples.

[Comparative Example 3]
In this comparative example, as the sulfuric acid-based copper electrolyte, a solution having a copper concentration of 80 g / l, a free sulfuric acid concentration of 140 g / l, a DDAC polymer (Unica FPA100L manufactured by Senca Co., Ltd.) and a chlorine concentration of 15 ppm was used. The anode was electrolyzed using a DSA electrode at a liquid temperature of 50 ° C. and a current density of 60 A / dm ² to obtain an electrolytic copper foil having a thickness of 12 μm. Table 2 shows the mechanical properties of this electrolytic copper foil, and Table 3 shows the surface roughness (Rzjis), glossiness, etc. of the deposited surface together with examples.

[Comparative Example 4]
In this comparative example, as the sulfuric acid-based copper electrolyte, the copper concentration was 80 g / l, the free sulfuric acid concentration was 140 g / l, the DDAC polymer (Unisense FPA100L manufactured by Senca Co., Ltd.) concentration, the low molecular weight glue (number average molecular weight 1560) concentration A solution with 6 ppm and a chlorine concentration of 15 ppm was used. The anode was electrolyzed using a DSA electrode at a liquid temperature of 50 ° C. and a current density of 60 A / dm ² to obtain an electrolytic copper foil having a thickness of 12 μm. The mechanical properties of this electrolytic copper foil are shown in Table 2, and the surface roughness (Rzjis) and glossiness [Gs (60 °)] of the deposition surface are shown in Table 3 together with examples.

[Comparative Example 5]
This comparative example is a trace experiment of Example 4 described in Patent Document 2. The basic solution of the sulfuric acid-based copper electrolyte solution was obtained by dissolving copper sulfate (reagent) and sulfuric acid (reagent) in pure water to have a copper sulfate (pentahydrate equivalent) concentration of 280 g / l and a free sulfuric acid concentration of 90 g / l. This is a copolymer of diallyldialkylammonium salt and sulfur dioxide (manufactured by Nitto Boseki Co., Ltd., trade name PAS-A-5, weight average molecular weight 4000) concentration 4 ppm, polyethylene glycol (average molecular weight 1000) concentration 10 ppm, MPS-Na. The concentration was adjusted to 1 ppm, and the chlorine concentration was further adjusted to 20 ppm using sodium chloride.

Then, a lead plate is used for the anode, and the above electrolytic solution is electrolyzed at a liquid temperature of 40 ° C. and a current density of 50 A / dm ² to obtain electrolytic copper foils having thicknesses of 12 μm and 70 μm, and then the same as in Example 10. Thus, two types of surface-treated electrolytic copper foil were obtained. The normal state of this electrolytic copper foil and 180 ° C. × 60 min. Table 5 shows the mechanical properties after heating, and the surface roughness (Rzjis), gloss [Gs (20 °)], [Gs (60 °)] and [Gs (85 °) of the electrolytic copper foil deposition surface. ], Surface roughness (Rzjis) and glossiness [Gs (60 °)] of the precipitation surface after surface treatment, and surface roughness (Rzjis) of the roughened surface of the roughened foil are shown in Table 6.

[Contrast between Example and Comparative Example]
Hereinafter, each comparative example and the example will be compared and the results will be described. In addition, as for the precipitation side of the electrolytic copper foil obtained in the Example, the surface roughness (Rzjis) <1.0 μm, the gloss [Gs (60 °)] ≧ 400, and the TD / MD ratio thereof is 0.9 to 1. .1 and [Gs (20 °)]> [Gs (60 °)]> [Gs (85 °)] The conditions of the present invention are satisfied. As for the mechanical properties, the normal mechanical properties are tensile strength of 33 kgf / mm ² or more and elongation of 5% or more, and the mechanical properties after heating are tensile strength of 30 kgf / mm ² or more and elongation of 8%. The above conditions of the present invention are satisfied.

Comparison between Examples and Comparative Example 1: When the surface roughness (Rzjis) on the deposition surface side of the electrolytic copper foil is compared, the electrolytic copper foil of Comparative Example 1 has a good low profile. However, the surface roughness (Rzjis) of the deposited surface of the 12 μm electrolytic copper foil according to the present invention is 0.30 μm to 0.41 μm, whereas the surface roughness (Rzjis) of the deposited surface of the 12 μm electrolytic copper foil of Comparative Example 1 is 0. The surface roughness (Rzjis) of the deposition surface of the 210 μm electrolytic copper foil according to the present invention is .85 μm, while the surface roughness (Rzjis) of the deposition surface of the 210 μm electrolytic copper foil of Comparative Example 1 is 0.27 μm to 0.34 μm. 0.70 μm. Therefore, although the tendency that a smoother precipitation surface is obtained as the copper foil thickness increases is common, the electrolytic copper foil according to the present invention is superior in the absolute value of smoothness. Further, when the glossiness [Gs (60 °)] is compared, the glossiness [Gs (60 °)] of Comparative Example 1 is in the range of 221 to 283, whereas the glossiness [Gs (60 °)] indicates a completely different range of 603 to 759. From this, it can be said that each of the electrolytic copper foils of the examples has a more flat and nearly precipitated surface compared to the electrolytic copper foil of Comparative Example 1. And as for mechanical properties, the 12 μm electrolytic copper foil of Comparative Example 1 is in a normal state with a tensile strength of 36.2 kgf / mm ² and an elongation of 4.0%, and after heating, a tensile strength of 32.4 kgf / mm ² and an elongation. The rate is 5.6%, and only the tensile strength in the normal state can be said to be equivalent to the electrolytic copper foil of the example.

Comparison between Example and Comparative Example 2: When the surface roughness (Rzjis) on the deposition surface side of the electrolytic copper foil is compared, the electrolytic copper foil of Comparative Example 2 has a good low profile. However, the surface roughness (Rzjis) of the deposition surface of the 12 μm electrolytic copper foil according to the present invention is 0.30 μm to 0.41 μm, whereas the surface roughness (Rzjis) of the deposition surface of the 12 μm electrolytic copper foil of Comparative Example 2 is 0. The surface roughness (Rzjis) of the deposited surface of the 210 μm electrolytic copper foil according to the present invention is 0.27 μm to 0.34 μm, whereas the surface roughness (Rzjis) of the deposited surface of the 210 μm electrolytic copper foil of Comparative Example 2 is 0.83 μm. 1.22 μm. Therefore, in Comparative Example 2, it is considered that it is difficult to obtain a stable and smooth electrolytic copper foil because the smoothness of the deposited surface is impaired by increasing the copper foil thickness. As for mechanical properties, the 12 μm electrolytic copper foil of Comparative Example 2 is in a normal state with a tensile strength of 31.4 kgf / mm ² and an elongation of 3.5%, and after heating, a tensile strength of 26.8 kgf / mm ² and elongation. The rate is 5.8%, and the electrolytic copper foils of the examples are superior.

Comparison between Example and Comparative Example 3 Comparative Example 3 is for observing the effect when MPS or SPS is not present in the copper electrolyte. As is apparent from Table 3, the surface roughness (Rzjis) of the deposited surface of the electrolytic copper foil obtained in Comparative Example 3 in which MPS or the like is not included in the copper electrolyte solution is 3.60 μm, which is a low profile. Has not been achieved. Further, the glossiness [Gs (60 °)] is almost matte and thus shows a very low value of 0.7. The mechanical properties of the 12 μm electrolytic copper foil have a large tensile strength of 40.5 kgf / mm ² , but the elongation is low at 3.6%, and the change due to heating is small. Therefore, it can be said that the electrolytic copper foil according to the present invention is superior in surface roughness and elongation.

Comparison between Example and Comparative Example 4 Comparative Example 4 shows the effect when low molecular weight glue is added to the copper electrolyte instead of MPS. As a result, as clearly shown in Table 3, even when low molecular weight glue is included in the copper electrolyte instead of MPS, the surface roughness (Rzjis) of the deposited surface of the electrolytic copper foil is 3.59 μm. And low profile is not achieved. Further, since the glossiness [Gs (60 °)] is almost matte, it shows a very low value of 1.0. In the mechanical properties, the normal tensile strength is 38.6 kgf / mm ^2, which is the same value as that of the example, but the elongation is as low as 4.0%. It is. Therefore, it can be said that the electrolytic copper foil according to the present invention is superior in surface roughness and elongation.

Comparison between Example and Comparative Example 5: The Example and Comparative Example 5 are compared between 12 μm electrolytic copper foils with reference to the data shown in Table 5 and Table 6 below.

When the surface roughness (Rzjis) on the precipitation surface side is compared, it is 0.30 μm to 0.41 μm in the electrolytic copper foil obtained in the example, and the surface roughness of the precipitation surface in the electrolytic copper foil obtained in Comparative Example 5 The difference (Rzjis) is 1.00 μm, which is obvious. And even if only the glossiness of the precipitation surface side is [Gs (60 °)], the electrolytic copper foil obtained in Comparative Example 5 is in the range of 324 to 383, whereas the electrolysis obtained in Examples is used. In copper foil, it exists in the completely different range of 603-759. That is, compared with the electrolytic copper foil of the comparative example 5, the electrolytic copper foil of an Example is provided with the precipitation surface which is flatter and close | similar to a mirror surface. The normal mechanical properties were as follows: the tensile strength of the electrolytic copper foil of Comparative Example 5 was 37.9 kgf / mm ² , and the elongation was 8.0%. The electrolytic copper foil of Example 10 had a tensile strength of 35.5 kgf / mm ² . mm ² , and the elongation is 11.5%, which is somewhat flexible. And 180 ° C. × 60 min. The mechanical properties after heating were as follows: the tensile strength of the electrolytic copper foil of Comparative Example 5 was 31.6 kgf / mm ² and the elongation was 7.5%. The electrolytic copper foil of Example 10 had a tensile strength of 33.2 kgf / mm ² . mm ² and the elongation percentage are 11.2%, and the electrolytic copper foil according to the present invention is superior. From this result, considering the thermal history when processed into a copper-clad laminate, for example, a flexible printed wiring board using the electrolytic copper foil according to the present invention can be expected to have excellent bending resistance.

  Next, the superiority of using three kinds of glossiness as an index for measuring the surface uniformity was confirmed. When the difference in glossiness is seen with MD as a common direction on the deposition surface of the 12 μm electrolytic foil obtained in the example, it is 824 to 1206 in [Gs (20 °)], 649 to 759 in [Gs (60 °)], and [Gs (85 °)] is 112 to 142, and becomes larger as the incident angle of the measurement light approaches perpendicularly. On the other hand, when the evaluation result when measured in the MD direction on the deposition surface side of the 12 μm electrolytic copper foil obtained in Comparative Example 5 is 126 in [Gs (20 °)], [Gs (60 °). )] Is 383 and [Gs (85 °)] is 117, and [Gs (20 °)] and [Gs (85 °)] are almost equal. Therefore, the deposition surface of the 12 μm electrolytic copper foil obtained in Comparative Example 5 has some characteristic shape.

  Therefore, FIG. 1 shows an SEM photograph of the 12 μm electrolytic copper foil deposited surface obtained in Example 11, and FIG. 2 shows an SEM photograph of the 12 μm electrolytic copper foil deposited surface obtained in Comparative Example 5. As can be seen from FIG. 2, irregularities are observed on the surface of the electrolytic copper foil obtained in Comparative Example 5 although they are small, and there are some abnormal precipitates that cannot be found unless observed at a high magnification. That is, the irregular reflection of light at the uneven portion decreases the glossiness [Gs (20 °)] value and increases the surface roughness (Rzjis). And in FIG. 1 which is the SEM photograph of the electrolytic copper foil which concerns on this invention, clear unevenness | corrugation is not observed and the abnormal precipitation part is not observed. Therefore, the electrolytic copper foil according to the present invention has excellent surface roughness and glossiness.

  Then, comparing the surface-treated electrolytic copper foil subjected to the roughening treatment, in comparison between Example 10 and Comparative Example 5, the value of the surface roughness (Rzjis) by the roughening treatment carried out under the same conditions The increase width is about 0.7 μm, which is almost the same. As can be seen from FIG. 2, the irregularities seen in the shape of the deposited surface of the electrolytic copper foil obtained in Comparative Example 5 have a pitch of about 3 μm but are flat, so that the fine particles obtained by the roughening treatment are respectively It can be assumed that this is because it adheres along the uneven shape. However, since the electrolytic copper foil of Comparative Example 5 has a large surface roughness (Rzjis) of the precipitation surface serving as a base, the surface roughness (Rzjis) of the adhesion surface with the insulating layer constituting material, which is a requirement of the present invention, is 1. It cannot be made 5 μm or less, and the superiority of the electrolytic copper foil according to the present invention is clear.

Comparison of MPS and SPS: In Examples 9 to 14, SPS was used as an alternative to MPS, but the obtained 12 μm electrolytic copper foil had a surface roughness (Rzjis) of the deposited surface of 0.30 μm to 0. 0. 41 [mu] m and glossiness [Gs (60 [deg.])] Are 603 to 759, and it has been confirmed that the same effect as MPS can be obtained even when SPS is used.

  In addition, in the said Example, in the manufacture of the electrolytic copper foil which concerns on this invention, the copper structure of sulfuric acid type copper electrolyte solution made 40 g / l-120 g / l, and the free sulfuric acid density | concentration made about 60 g / l-220 g / l. Although good results have been obtained, the concentration range may be changed according to the intended application. And it does not deny the presence of additives other than the additives described in the above examples, it can further emphasize the effects of the additives, can contribute to quality stabilization during continuous production, etc. If it is confirmed, it may be added arbitrarily.

Deposition surface of the electrolytic copper foil obtained by a manufacturing method as engagement Ru electrolytic copper foil to the present invention is a further low profile compared with low-profile electrodeposited copper foil which has been supplied to the conventional market, roughness of the deposition surface Becomes less than the roughness of the glossy surface, and both surfaces are glossy and smooth. And the copper electrolyte solution used for manufacture of electrolytic foil has a large adaptability with respect to variations in manufacturing conditions and variations in thickness, and is excellent in productivity. Therefore, it is suitable for forming a fine pitch circuit of a tape automated bonding (TAB) substrate and a chip on film (COF) substrate, and further, an electromagnetic wave shielding circuit of a plasma display panel. And since this electrolytic copper foil has the outstanding mechanical characteristic, it is suitable also for the use as a current collection material which comprises negative electrodes, such as a lithium ion secondary battery.

2 is a SEM photograph of a 12 μm electrolytic copper foil deposition surface obtained in Example 11. FIG. 6 is a SEM photograph of a 12 μm electrolytic copper foil deposition surface obtained in Comparative Example 5.

Claims (15)

A method for producing an electrolytic copper foil by peeling off copper deposited on the cathode surface by an electrolytic method using a sulfuric acid-based copper electrolyte,
The sulfuric acid-based copper electrolytic solution is diallyldimethylammonium chloride heavy, which is a quaternary ammonium salt polymer having a cyclic structure and at least one selected from 3-mercapto-1-propanesulfonic acid or bis (3-sulfopropyl) disulfide. A method for producing an electrolytic copper foil, comprising coalescence and chlorine. According to claim 1, wherein the combined concentration of the 3-mercapto-1-propanesulfonic acid and / or bis (3-sulfopropyl) disulfide of the sulfuric acid base copper electrolytic solution is 0.5ppm~100ppm Manufacturing method of electrolytic copper foil. The method for producing an electrolytic copper foil according to claim 1 or 2 , wherein a concentration of the quaternary ammonium salt polymer having a cyclic structure in the sulfuric acid-based copper electrolyte is 1 ppm to 150 ppm. The method for producing an electrolytic copper foil according to any one of claims 1 to 3 , wherein a chlorine concentration in the sulfuric acid-based copper electrolytic solution is 5 ppm to 120 ppm. An electrolytic copper foil manufactured by the manufacturing method according to claim 1 . A surface-treated electrolytic copper foil obtained by performing at least one of rust prevention treatment and silane coupling agent treatment on the surface of the electrolytic copper foil according to claim 5 . The surface-treated electrolytic copper foil according to claim 6 , wherein the surface-treated electrolytic copper foil has a surface roughness (Rzjis) of an adhesion surface with an insulating layer constituting material of 1.5 µm or less. 8. The surface-treated electrolytic copper foil according to claim 6, wherein a glossiness [Gs (60 °)] of an adhesion surface between the surface-treated electrolytic copper foil and the insulating layer constituting material is 250 or more. . The surface-treated electrolytic copper foil according to claim 6 , wherein the surface-treated electrolytic copper foil is subjected to a roughening treatment on an adhesive surface side with the insulating layer constituting material. The surface-treated electrolytic copper foil according to any one of claims 6 to 9 , wherein an adhesive surface of the surface-treated electrolytic copper foil with the insulating layer constituting material is a deposited surface side of the electrolytic copper foil. A copper-clad laminate obtained by bonding the surface-treated electrolytic copper foil according to any one of claims 6 to 9 to an insulating layer constituting material. The rigid copper clad laminate according to claim 11 , wherein the insulating layer constituent material contains a skeleton material. A rigid printed wiring board obtained by using the rigid copper-clad laminate according to claim 12 . The flexible copper clad laminate according to claim 11 , wherein the insulating layer constituting material is made of a flexible material having flexibility. A flexible printed wiring board obtained by using the flexible copper-clad laminate according to claim 14 .