JPWO2013176133A1 - Surface-treated copper foil, laminate using the same, printed wiring board, electronic device, and method for producing printed wiring board - Google Patents

Abstract

Provided are a surface-treated copper foil that adheres well to a resin and is excellent in the transparency of a resin after the copper foil is removed by etching, and a laminate using the same. The surface-treated copper foil is a 50 μm thick polyimide from the surface of the roughened surface (the following ΔB (PI) is 20 or more and 33 or less before being bonded to the copper foil). In a direction perpendicular to the direction in which the observed line-shaped mark extends in an image taken with a CCD camera over the polyimide substrate, which is a printed product printed with a line-shaped mark laid under the exposed polyimide substrate The difference ΔB between the top average value Bt and the bottom average value Bb of the lightness curve generated from the end of the mark to the portion where no mark is drawn in the observation point-lightness graph in which the lightness at each observation point is measured along 20 or more, ΔB / ΔB (PI) is 0.7 or more, and the slope of the lightness curve in the depth range of 0.4ΔB to 0.6ΔB with reference to Bt is 65 to 87.

Description

  The present invention relates to a surface-treated copper foil and a method for producing a laminate, a printed wiring board, an electronic device and a printed wiring board using the surface-treated copper foil, and in particular, the transparency of the remaining resin after etching the copper foil is required. In particular, the present invention relates to a surface-treated copper foil suitable for various fields, a laminated board using the copper foil, a printed wiring board, an electronic device, and a method for producing a printed wiring board.

  In a small electronic device such as a smartphone or a tablet PC, a flexible printed wiring board (hereinafter referred to as FPC) is adopted because of easy wiring and light weight. In recent years, with the enhancement of functions of these electronic devices, the signal transmission speed has been increased, and impedance matching has become an important factor in FPC. As a measure for impedance matching with respect to an increase in signal capacity, a resin insulation layer (for example, polyimide) serving as a base of an FPC has been increased in thickness. On the other hand, processing such as bonding to a liquid crystal substrate and mounting of an IC chip is performed on the FPC, but the alignment at this time is the resin insulation remaining after etching the copper foil in the laminate of the copper foil and the resin insulating layer The visibility of the resin insulation layer is important because it is performed through a positioning pattern that is visible through the layer.

  Moreover, the copper clad laminated board which is a laminated board of copper foil and a resin insulating layer can also be manufactured even if it uses the rolled copper foil by which roughening plating was given to the surface. This rolled copper foil usually uses tough pitch copper (oxygen content of 100 to 500 ppm by weight) or oxygen-free copper (oxygen content of 10 ppm by weight or less) as a raw material, and after hot rolling these ingots, It is manufactured by repeating cold rolling and annealing to a thickness.

As such a technique, for example, in Patent Document 1, a polyimide film and a low-roughness copper foil are laminated, and a light transmittance at a wavelength of 600 nm of the film after copper foil etching is 40% or more, a haze value. An invention relating to a copper clad laminate having (HAZE) of 30% or less and an adhesive strength of 500 N / m or more is disclosed.
Further, Patent Document 2 has an insulating layer in which a conductive layer made of electrolytic copper foil is laminated, and the light transmittance of the insulating layer in the etching region when the circuit is formed by etching the conductive layer is 50% or more. In a flexible printed wiring board for chip-on-flex (COF), the electrolytic copper foil has a rust-proofing layer made of a nickel-zinc alloy on an adhesive surface bonded to an insulating layer, and the surface roughness (Rz) of the adhesive surface ) Is 0.05 to 1.5 μm, and the specular gloss at an incident angle of 60 ° is 250 or more, and an invention relating to a flexible printed wiring board for COF is disclosed.
Moreover, in patent document 3, in the processing method of the copper foil for printed circuits, after the roughening process by copper-cobalt-nickel alloy plating on the surface of copper foil, a cobalt-nickel alloy plating layer is formed, and also zinc-nickel An invention relating to a method for treating a copper foil for printed circuit, characterized by forming an alloy plating layer is disclosed.

JP 2004-98659 A WO2003 / 096776 Japanese Patent No. 2849059

In Patent Document 1, a low-roughness copper foil obtained by improving adhesion with an organic treatment agent after blackening treatment or plating treatment is broken due to fatigue in applications where flexibility is required for a copper-clad laminate. May be inferior in resin transparency.
Moreover, in patent document 2, the roughening process is not made and the adhesive strength of copper foil and resin is low and inadequate in uses other than the flexible printed wiring board for COF.
Furthermore, in the processing method described in Patent Document 3, Cu-Co-Ni fine processing on the copper foil was possible, but the resin after bonding the copper foil with the resin and removing it by etching was excellent. Transparency is not realized.
The present invention provides a surface-treated copper foil that adheres well to a resin and is excellent in the transparency of a resin after the copper foil is removed by etching, and a laminate using the same.

  As a result of intensive studies, the inventors have placed a printed matter with a mark on the polyimide substrate from which the copper foil has been bonded and removed, and the mark portion taken by the CCD camera through the polyimide substrate. Paying attention to the slope of the brightness curve near the mark edge drawn in the observation point-brightness graph obtained from the image of the image, controlling the slope of the brightness curve affects the resin transparency after the copper foil is etched away Found to affect.

  The present invention completed on the basis of the above knowledge is, in one aspect, a surface-treated copper foil in which roughened particles are formed on at least one surface by a roughening treatment, and the copper foil is roughened on the surface side of the roughened surface. To 50 μm thick polyimide (polyimide having the following ΔB (PI) of 20 to 33 for the polyimide before being laminated to the copper foil) after bonding to both sides of the substrate, the copper foil on both sides is removed by etching, When the printed matter on which a line-shaped mark is printed is laid under the exposed polyimide substrate and the printed matter is photographed with a CCD camera through the polyimide substrate, the line observed for the image obtained by the photographing is observed. In the observation point-brightness graph produced by measuring the brightness at each observation point along the direction perpendicular to the direction in which the mark is extended, the edge of the mark The difference ΔB (ΔB = Bt−Bb) between the top average value Bt and the bottom average value Bb of the brightness curve generated from the part to the part where the mark is not drawn is 20 or more, and the ratio is ΔB / ΔB (PI) Is a surface-treated copper foil in which the slope (angle) k1 of the lightness curve in the depth range of 0.4 ΔB to 0.6 ΔB with respect to Bt is 65 ° or more and 87 ° or less.

  In another aspect, the present invention is a laminated plate configured by laminating the surface-treated copper foil of the present invention and a resin substrate.

  In yet another aspect, the present invention is a printed wiring board using the surface-treated copper foil of the present invention.

  In still another aspect, the present invention is an electronic device using the printed wiring board of the present invention.

  In yet another aspect, the present invention is a method of manufacturing a printed wiring board in which two or more printed wiring boards are connected by connecting two or more printed wiring boards of the present invention.

  In yet another aspect, the present invention includes a step of connecting at least one printed wiring board of the present invention and another printed wiring board of the present invention or a printed wiring board not corresponding to the printed wiring board of the present invention. This is a method of manufacturing a printed wiring board in which two or more printed wiring boards are connected.

  In still another aspect, the present invention is an electronic apparatus using one or more printed wiring boards to which at least one printed wiring board of the present invention is connected.

  In still another aspect, the present invention is a method for manufacturing a printed wiring board, comprising at least a step of connecting the printed wiring board of the present invention and a component.

  In yet another aspect of the present invention, the step of connecting at least one printed wiring board of the present invention to another printed wiring board of the present invention or a printed wiring board not corresponding to the printed wiring board of the present invention, and And manufacturing a printed wiring board having two or more printed wiring boards connected, comprising at least a step of connecting the printed wiring board of the present invention or two or more of the printed wiring boards of the present invention and a component. Is the method.

  ADVANTAGE OF THE INVENTION According to this invention, the surface-treated copper foil excellent in transparency of resin after adhere | attaching resin favorably and removing copper foil by an etching, and a laminated board using the same can be provided.

It is a schematic diagram which defines Bt and Bb. It is a schematic diagram which defines k1 and k2. It is a schematic diagram showing the structure of an imaging device and the measuring method of the inclination of a lightness curve in the case of evaluation of the lightness curve inclination. It is a SEM observation photograph of the copper foil surface of (a) comparative example 1 in the case of Rz evaluation. It is a SEM observation photograph of the copper foil surface of (b) comparative example 2 in the case of Rz evaluation. It is a SEM observation photograph on the surface of copper foil of (c) comparative example 3 in the case of Rz evaluation. It is a SEM observation photograph on the surface of copper foil of (d) comparative example 4 in the case of Rz evaluation. (E) It is a SEM observation photograph of the copper foil surface of Example 1 in the case of Rz evaluation. (F) It is a SEM observation photograph of the copper foil surface of Example 2 in the case of Rz evaluation.

[Form and manufacturing method of surface-treated copper foil]
The copper foil used in the present invention is useful for a copper foil used by making a laminate by bonding to a resin substrate and removing it by etching.
The copper foil used in the present invention may be either an electrolytic copper foil or a rolled copper foil. Usually, the surface of the copper foil that adheres to the resin substrate, that is, the roughened surface, has a fist-like electric surface on the surface of the copper foil after degreasing in order to improve the peel strength of the copper foil after lamination. A roughening process is carried out to wear. Although the electrolytic copper foil has irregularities at the time of manufacture, the irregularities are further increased by enhancing the convex portions of the electrolytic copper foil by roughening treatment. In the present invention, this roughening treatment can be performed by copper-cobalt-nickel alloy plating, copper-nickel-phosphorus alloy plating, or the like. Ordinary copper plating or the like may be performed as a pretreatment before roughening, and ordinary copper plating or the like may be performed as a finishing treatment after roughening in order to prevent electrodeposits from dropping off. The content of treatment may be somewhat different between the rolled copper foil and the electrolytic copper foil. In the present invention, including such pretreatment and finishing treatment, known treatments related to copper foil roughening are included as necessary, and are collectively referred to as roughening treatment.
The rolled copper foil according to the present invention includes a copper alloy foil containing one or more elements such as Ag, Sn, In, Ti, Zn, Zr, Fe, P, Ni, Si, Te, Cr, Nb, V, and B. Is also included. When the concentration of the above elements increases (for example, 10% by mass or more in total), the conductivity may decrease. The conductivity of the rolled copper foil is preferably 50% IACS or more, more preferably 60% IACS or more, and still more preferably 80% IACS or more.

Copper as roughening treatment - cobalt - nickel alloy plating, by electrolytic plating, coating weight is to be the 15~40mg / dm ² of copper -100~3000μg / dm ² of cobalt -100~1500μg / dm ² of nickel It can be carried out so as to form a ternary alloy layer. If the amount of deposited Co is less than 100 μg / dm ² , the heat resistance may deteriorate and the etching property may deteriorate. When the amount of Co deposition exceeds 3000 μg / dm ² , it is not preferable when the influence of magnetism must be taken into account, etching spots may occur, and acid resistance and chemical resistance may deteriorate. If the Ni adhesion amount is less than 100 μg / dm ² , the heat resistance may deteriorate. On the other hand, when the Ni adhesion amount exceeds 1500 μg / dm ² , the etching residue may increase. A preferable Co adhesion amount is 1000 to 2500 μg / dm ² , and a preferable nickel adhesion amount is 500 to 1200 μg / dm ² . Here, the etching stain means that Co remains without being dissolved when etched with copper chloride, and the etching residue means that Ni remains without being dissolved when alkaline etching is performed with ammonium chloride. It means that.

An example of a general bath and plating conditions for forming such a ternary copper-cobalt-nickel alloy plating is as follows:
Plating bath composition: Cu 10-20 g / L, Co 1-10 g / L, Ni 1-10 g / L
pH: 1-4
Temperature: 30-50 ° C
Current density D _k : 20 to 30 A / dm ²
Plating time: 1 to 5 seconds Note that the surface-treated copper foil according to one embodiment of the present invention is subjected to a roughening treatment under conditions where the plating time is shorter than before and the current density is increased. By performing the roughening treatment under a condition in which the plating time is shortened and the current density is increased as compared with the conventional case, finer roughened particles are formed on the surface of the copper foil.

After the roughening treatment, a cobalt-nickel alloy plating layer of nickel having an adhesion amount of 200 to 3000 μg / dm ² and cobalt-100 to 700 μg / dm ² can be formed on the roughened surface. This treatment can be regarded as a kind of rust prevention treatment in a broad sense. This cobalt-nickel alloy plating layer needs to be performed to such an extent that the adhesive strength between the copper foil and the substrate is not substantially reduced. If the amount of cobalt adhesion is less than 200 μg / dm ² , the heat-resistant peel strength is lowered, and the oxidation resistance and chemical resistance may be deteriorated. As another reason, if the amount of cobalt is small, the treated surface becomes reddish, which is not preferable. When the amount of cobalt deposition exceeds 3000 μg / dm ² , it is not preferable when the influence of magnetism must be taken into account, and etching spots may occur, and acid resistance and chemical resistance may deteriorate. A preferable cobalt adhesion amount is 500 to 2500 μg / dm ² . On the other hand, when the nickel adhesion amount is less than 100 μg / dm ² , the heat-resistant peel strength is lowered, and the oxidation resistance and chemical resistance may be deteriorated. When nickel exceeds 1300 microgram / dm < ² >, alkali etching property will worsen. A preferable nickel adhesion amount is 200 to 1200 μg / dm ² .

An example of the conditions for cobalt-nickel alloy plating is as follows:
Plating bath composition: Co 1-20 g / L, Ni 1-20 g / L
pH: 1.5-3.5
Temperature: 30-80 ° C
Current density D _k : 1.0 to 20.0 A / dm ²
Plating time: 0.5-4 seconds

According to the present invention, a zinc plating layer having an adhesion amount of 30 to 250 μg / dm ² is further formed on the cobalt-nickel alloy plating. If the zinc adhesion amount is less than 30 μg / dm ² , the heat deterioration rate improving effect may be lost. On the other hand, when the zinc adhesion amount exceeds 250 μg / dm ² , the hydrochloric acid deterioration rate may be extremely deteriorated. Preferably, the zinc adhesion amount is 30 to 240 μg / dm ² , more preferably 80 to 220 μg / dm ² .

An example of the galvanizing conditions is as follows:
Plating bath composition: Zn 100 to 300 g / L
pH: 3-4
Temperature: 50-60 ° C
Current density D _k : 0.1 to 0.5 A / dm ²
Plating time: 1-3 seconds

  A zinc alloy plating layer such as zinc-nickel alloy plating may be formed instead of the zinc plating layer, and a rust prevention layer may be formed on the outermost surface by chromate treatment or application of a silane coupling agent. Good.

[Surface roughness Rz]
In the surface-treated copper foil of the present invention, it is preferable that roughened particles are formed on the surface of the copper foil by a roughening treatment, and that the average roughness Rz of TD on the roughened surface is 0.20 to 0.80 μm. . With such a configuration, the peel strength is increased and the resin is satisfactorily bonded to the resin, and the transparency of the resin after the copper foil is removed by etching is increased. As a result, alignment and the like when mounting an IC chip through a positioning pattern that is visible through the resin can be made easier. When the average roughness Rz of TD is less than 0.20 μm, there is a concern about manufacturing costs for producing an ultra-smooth surface. On the other hand, if the average roughness Rz of TD is more than 0.80 μm, the unevenness of the resin surface after the copper foil is removed by etching may increase, resulting in a problem that the transparency of the resin becomes poor. There is a fear. The average TD roughness Rz of the roughened surface is more preferably 0.30 to 0.70 μm, still more preferably 0.35 to 0.60 μm, still more preferably 0.35 to 0.55 μm, and Even more preferred is 35 to 0.50 μm.
In addition, when the surface-treated copper foil of this invention is used for the use which needs to make Rz small, the average roughness Rz of TD of the roughening surface of the surface-treated copper foil of this invention is 0.20. To 0.70 μm is preferable, 0.25 to 0.60 μm is more preferable, 0.30 to 0.60 μm is still more preferable, 0.30 to 0.55 μm is still more preferable, and 0.30 to 0.50 μm is more preferable. Even more preferred.

[Glossiness]
The glossiness at an incident angle of 60 degrees in the rolling direction (MD) of the roughened surface of the surface-treated copper foil greatly affects the transparency of the resin. That is, the greater the glossiness of the roughened surface, the better the transparency of the resin described above. For this reason, the surface-treated copper foil of the present invention preferably has a roughened surface having a glossiness of 76 to 350%, preferably 80 to 350%, more preferably 90 to 300%, It is still more preferable that it is 90 to 250%, and it is still more preferable that it is 100 to 250%.

Here, in order to further improve the visibility effect of the present invention, the TD roughness (Rz) and glossiness of the surface of the copper foil before the surface treatment on the treatment side may be controlled. Specifically, the surface roughness (Rz) of TD of the copper foil before the surface treatment is preferably 0.30 to 0.80 μm, more preferably 0.30 to 0.50 μm, and the rolling direction (MD) The glossiness at an incident angle of 60 degrees is preferably 350 to 800%, more preferably 500 to 800%, and if the current density is made higher than the conventional roughening treatment and the roughening treatment time is shortened, The glossiness at an incident angle of 60 degrees in the rolling direction (MD) of the surface-treated copper foil after the surface treatment is 90 to 350%. Such a copper foil can be produced by adjusting the oil film equivalent of rolling oil (high gloss rolling), or by chemical polishing such as chemical etching or electrolytic polishing in a phosphoric acid solution. Thus, it is easy to control the surface roughness (Rz) and the surface area of the copper foil after the treatment by setting the TD surface roughness (Rz) and the glossiness of the copper foil before the treatment within the above range. Can do.
When the surface roughness (Rz) of the copper foil after the surface treatment is desired to be smaller (for example, Rz = 0.20 μm), the TD roughness (Rz) of the treated side surface of the copper foil before the surface treatment is set. 0.18 to 0.80 μm, preferably 0.25 to 0.50 μm, and the glossiness at an incident angle of 60 degrees in the rolling direction (MD) is 350 to 800%, preferably 500 to 800%, The current density is made higher than that of the conventional roughening treatment, and the roughening treatment time is shortened.
Further, the copper foil before the roughening treatment preferably has an MD 60 degree gloss of 500 to 800%, more preferably 501 to 800%, and even more preferably 510 to 750%. . If the 60 degree glossiness of MD of the copper foil before the roughening treatment is less than 500%, the transparency of the resin may be poorer than the case of 500% or more. The problem that it becomes difficult may arise.
High gloss rolling can be performed by setting the oil film equivalent defined by the following formula to 13000 or more and 24000 or less. When the surface roughness (Rz) of the copper foil after the surface treatment is desired to be smaller (for example, Rz = 0.20 μm), the oil film equivalent defined by the following formula is set to 12000 to 24000 for high gloss rolling. To do.
Oil film equivalent = {(rolling oil viscosity [cSt]) × (sheet feeding speed [mpm] + roll peripheral speed [mpm])} / {(roll biting angle [rad]) × (yield stress of material [kg / mm ² ])}
The rolling oil viscosity [cSt] is a kinematic viscosity at 40 ° C.
In order to make the oil film equivalent 12000 or more and 24000 or less, a known method such as using a low viscosity rolling oil or slowing a sheet passing speed may be used.
Chemical polishing is performed over a long period of time using an etching solution such as sulfuric acid-hydrogen peroxide-water system or ammonia-hydrogen peroxide-water system at a concentration lower than usual.

  The ratio C (C = (60 degree gloss of MD) / (60 degree gloss of TD)) of the 60 degree gloss of MD and 60 degree gloss of TD on the roughened surface is 0.80 to 1. 40 is preferred. If the ratio C between the 60 ° glossiness of MD and the 60 ° glossiness of TD on the roughened surface is less than 0.80, the transparency of the resin may be lower than when the ratio C is 0.80 or more. . Further, if the ratio C is more than 1.40, the transparency of the resin may be lower than when the ratio C is 1.40 or less. The ratio C is more preferably 0.90 to 1.35, and even more preferably 1.00 to 1.30.

[Slope of brightness curve]
The surface-treated copper foil of the present invention is bonded to both surfaces of a substrate having a thickness of 50 μm from the surface of the roughened surface (polyimide having the following ΔB (PI) of 20 to 33 for the polyimide before being bonded to the copper foil). Then, the copper foil on both sides is removed by etching, and the printed matter on which the line-shaped mark is printed is laid under the exposed polyimide substrate, and when the printed matter is photographed with a CCD camera through the polyimide substrate, In the observation point-lightness graph prepared by measuring the brightness of each observation point along the direction perpendicular to the direction in which the observed line-shaped mark extends, the mark is drawn from the end of the mark. The difference ΔB (ΔB = Bt−Bb) between the top average value Bt and the bottom average value Bb of the lightness curve generated over the part that is not present is 20 or more, and ΔB / The ratio of ΔB (PI) is 0.7 or more, and the slope k1 of the brightness curve in the depth range of 0.4ΔB to 0.6ΔB with reference to Bt is 65 ° or more and 87 ° or less.
Here, “the top average value Bt of the lightness curve”, “the bottom average value Bb of the lightness curve”, “the slope k1 of the lightness curve”, and “the slope k2 of the lightness curve” described later will be described with reference to the drawings. .
FIG. 1 shows a schematic diagram defining Bt and Bb. The “mark” in FIG. 1 indicates a line-like mark (width of about 1.3 mm) of the printed matter observed in an image obtained by photographing with the CCD camera. A curve drawn so as to overlap the mark indicates a lightness curve generated from the end of the mark to a portion where no mark is drawn in the observation point-lightness graph. As shown in FIG. 1, the “top average value Bt of the lightness curve” is an average of lightness values measured at 5 points (a total of 10 points on both sides) at 30 μm intervals from a position 100 μm away from the end positions on both sides of the mark Indicates the value. The “bottom average value Bb of the lightness curve” indicates an average value of lightness when 11 positions are measured at intervals of 100 μm from a position inside 100 μm from the end position of the mark.
FIG. 2 shows a schematic diagram defining k1 and k2. “Brightness curve slope (angle) k1” is 0.4 ΔB to 0.6 ΔB based on Bt [ΔB is the difference between the top average value Bt and the bottom average value Bb of the lightness curve (ΔB = Bt−Bb)] The inclination (angle) of the lightness curve in the depth range is shown (k1 (°) = tan ⁻¹ (b (gradation) / a (pixel))). One pixel on the horizontal axis corresponds to a length of 10 μm. Then, the ratio of the length of one pixel to one gradation in the lightness curve graph is 3.5: 5 (the length of one pixel in the lightness curve graph: the length of one gradation in the lightness curve graph = 3. The value of k1 (°) was calculated in the lightness curve graph of 5: 5). Further, k1 is measured on both sides of the mark and adopts a value with a small inclination (angle). “Inclination (angle) k2 of the lightness curve” indicates the inclination (angle) of the lightness curve in the depth range from the intersection of the lightness curve and Bt to 0.1 ΔB with reference to Bt (k2 (°) = tan ^{− 1} (d (gradation) / c (pixel))). One pixel on the horizontal axis corresponds to a length of 10 μm. Then, the ratio of the length of one pixel to one gradation in the lightness curve graph is 3.5: 5 (the length of one pixel in the lightness curve graph: the length of one gradation in the lightness curve graph = 3. The value of k1 (°) was calculated in the lightness curve graph of 5: 5). Also, k2 is measured on both sides of the mark, and a value with a small inclination (angle) is adopted. Further, when the shape of the lightness curve is unstable and there are a plurality of the “intersections between the lightness curve and Bt”, the intersection closest to the mark is adopted.
ΔB (PI) represents the difference between the top average value Bt and the bottom average value Bb of the brightness curve for the polyimide before being bonded to the copper foil.
In the image taken by the CCD camera, the brightness is high at the portion where the mark is not attached, but the brightness decreases as soon as the end of the mark is reached. If the visibility of the polyimide substrate is good, such a lowered state of brightness is clearly observed. On the other hand, if the visibility of the polyimide substrate is poor, the lightness does not suddenly drop from “high” to “low” in the vicinity of the mark end, but the state of decline is slow and the state of lightness decline is unclear. End up.
Based on such knowledge, the present invention is based on such a polyimide substrate from which the surface-treated copper foil of the present invention is bonded and removed, and a mark printed matter is placed under the polyimide substrate and photographed with a CCD camera over the polyimide substrate. The inclination of the lightness curve near the mark end portion drawn in the observation point-lightness graph obtained from the image is controlled. More specifically, the difference ΔB (ΔB = Bt−Bb) between the top average value Bt and the bottom average value Bb of the lightness curve is set to 20 or more, the ratio of ΔB / ΔB (PI) is set to 0.7 or more, and Bt Is controlled so that the slope (angle) k1 of the brightness curve in the depth range of 0.4ΔB to 0.6ΔB is 65 ° or more and 87 ° or less. According to such a configuration, the discriminating power of the mark over the polyimide by the CCD camera is improved. For this reason, it is possible to produce a polyimide substrate with excellent visibility, and the positioning accuracy by marking when performing a predetermined treatment on the polyimide substrate in an electronic substrate manufacturing process or the like is improved, thereby improving the yield. can get. ΔB is preferably 28 or more, and k1 is preferably 75 ° or more and 87 ° or less. The upper limit of ΔB is not particularly limited, but is, for example, 100 or less, 60 or less, or 50 or less, or 40 or less. The upper limit of k1 is preferably 87 ° or less, more preferably 85 ° or less, and even more preferably 83 ° or less. When k1 exceeds 87 °, the peel strength may be reduced. The upper limit of ΔB / ΔB (PI) need not be specified, but is, for example, 1.70 or less, or 1.50 or less, or 1.40 or less.

  Further, in an observation point-lightness graph prepared from an image obtained by photographing, the slope k2 of the lightness curve in a depth range from the intersection of the lightness curve and Bt to 0.1 ΔB with respect to Bt is 30 ° or more. Is preferred. According to such a configuration, the boundary between the mark and the non-mark portion becomes clearer, the positioning accuracy is improved, the error due to the mark image recognition is reduced, and the alignment can be performed more accurately. k2 is more preferably 40 ° or more. The upper limit of k2 is not particularly limited, but is, for example, 87 ° or less, alternatively 82 ° or less, alternatively 77 ° or less, or 72 ° or less.

[Particle surface area]
The ratio A / B between the surface area A of the roughened particles and the area B obtained when the roughened particles are viewed in plan from the copper foil surface side greatly affects the transparency of the resin. That is, if the surface roughness Rz is the same, the smaller the ratio A / B, the better the transparency of the resin. For this reason, as for the surface-treated copper foil of this invention, it is preferable that the said ratio A / B is 1.90-2.40, and it is more preferable that it is 2.00-2.20.

  By controlling the current density and the plating time during particle formation, the particle morphology and formation density are determined, and the surface roughness Rz, glossiness, and particle area ratio A / B can be controlled.

  As described above, the ratio A / B between the surface area A of the roughened particles and the area B obtained when the roughened particles are viewed in plan view from the copper foil surface side is controlled to 1.90 to 2.40. The roughness of the roughened surface is controlled to 0.30 to 0.80 μm to eliminate extremely rough portions, while the glossiness of the roughened surface is increased. It can be as high as 80 to 350%. By performing such control, in the surface-treated copper foil of the present invention, the particle size of the roughened particles on the roughened surface can be reduced. The particle size of the roughened particles affects the resin transparency after the copper foil is removed by etching, but such control means that the particle size of the roughened particles is reduced within an appropriate range. Therefore, the resin transparency after removing the copper foil by etching becomes better, and the peel strength becomes better.

[Etching factor]
When the value of the etching factor when forming a circuit using copper foil is large, the bottom of the circuit that occurs during etching is reduced, so that the space between the circuits can be narrowed. Therefore, a larger etching factor is preferable because it is suitable for forming a circuit with a fine pattern. In the surface-treated copper foil of the present invention, for example, the etching factor is preferably 1.8 or more, preferably 2.0 or more, preferably 2.2 or more, and 2.3 or more. Preferably, it is 2.4 or more.
In the printed wiring board or copper-clad laminate, the above-mentioned particle area ratio (A / B), glossiness, and surface roughness Rz are obtained for the copper circuit or copper foil surface by dissolving and removing the resin. Can be measured.

[Transmission loss]
When the transmission loss is small, attenuation of the signal when performing signal transmission at a high frequency is suppressed, so that a stable signal transmission can be performed in a circuit that transmits the signal at a high frequency. Therefore, a smaller transmission loss value is preferable because it is suitable for use in a circuit for transmitting a signal at a high frequency. After bonding the surface-treated copper foil to a commercially available liquid crystal polymer resin (Vecstar CTZ-50 μm manufactured by Kuraray Co., Ltd.), a microstrip line is formed by etching so that the characteristic impedance is 50Ω, and a network manufactured by HP When the transmission coefficient was measured using the analyzer HP8720C and the transmission loss at a frequency of 20 GHz was determined, the transmission loss at a frequency of 20 GHz is preferably less than 5.0 dB / 10 cm, more preferably less than 4.1 dB / 10 cm. Even more preferred is less than 0.7 dB / 10 cm.

The surface-treated copper foil of the present invention can be bonded to a resin substrate from the roughened surface side to produce a laminate. The resin substrate is not particularly limited as long as it has characteristics applicable to a printed wiring board or the like. For example, a paper base phenol resin, a paper base epoxy resin, a synthetic fiber cloth base epoxy resin for rigid PWB Glass cloth / paper composite base material epoxy resin, glass cloth / glass nonwoven fabric composite base material epoxy resin and glass cloth base material epoxy resin, etc. are used, polyester film, polyimide film, liquid crystal polymer (LCP) film, fluorine for FPC Resin etc. can be used. In addition, when a liquid crystal polymer (LCP) film or a fluororesin film is used, the peel strength between the film and the surface-treated copper foil tends to be smaller than when a polyimide film is used. Therefore, when a liquid crystal polymer (LCP) film or a fluororesin film is used, the surface-treated copper foil is etched to form a copper circuit, and then the copper circuit is covered with a cover lay to cover the film and the copper The circuit is difficult to peel off, and peeling of the film and the copper circuit due to a decrease in peel strength can be prevented.
Resins with good dielectric properties (low dielectric loss tangent (for example, dielectric loss tangent is 0.008 or less) and / or low relative dielectric constant (for example, 3 or less when the signal frequency is 25 GHz)) or low dielectric resin (Resin having a small relative dielectric constant (for example, 3 or less when the signal frequency is 25 GHz)) has a small dielectric loss. Therefore, copper-clad laminates, printed wiring boards, and printed circuit boards using a resin, low dielectric resin or low dielectric loss resin with good dielectric properties and the surface-treated copper foil according to the present invention are high frequency circuits (signals at high frequencies). Suitable for transmission circuit). Here, the low dielectric loss resin refers to a resin having a dielectric loss smaller than that of polyimide conventionally used for a copper clad laminate. Further, the surface-treated copper foil according to the present invention has a small surface roughness Rz and a high glossiness, so that the surface is smooth and suitable for high-frequency circuit applications. Examples of the resin having good dielectric characteristics, the low dielectric resin, or the low dielectric loss resin include a liquid crystal polymer (LCP) film and a fluororesin film.
In addition, the surface-treated copper foil of this invention can be used suitably for all the uses. For example, it can be used for printed wiring boards, printed circuit boards, printed wiring boards for high frequency circuits, printed circuit boards, semiconductor package substrates, secondary batteries, capacitor electrodes, and the like.

  In the case of the rigid PWB, a prepreg is prepared by impregnating a base material such as a glass cloth with a resin and curing the resin to a semi-cured state. It can be carried out by superposing a copper foil on the prepreg from the opposite surface of the coating layer and heating and pressing. In the case of FPC, it is laminated on a copper foil under high temperature and high pressure without using an adhesive on a substrate such as a polyimide film, or a polyimide precursor is applied, dried, cured, etc. A laminated board can be manufactured by performing.

  The laminate of the present invention can be used for various printed wiring boards (PWB) and is not particularly limited. For example, from the viewpoint of the number of layers of the conductor pattern, the single-sided PWB, the double-sided PWB, and the multilayer PWB (3 It is applicable to rigid PWB, flexible PWB (FPC), and rigid flex PWB from the viewpoint of the type of insulating substrate material.

[Lamination board and printed wiring board positioning method using the same]
A method for positioning the laminate of the surface-treated copper foil and the resin substrate of the present invention will be described. First, a laminate of a surface-treated copper foil and a resin substrate is prepared. As a specific example of the laminate of the surface-treated copper foil and the resin substrate according to the present invention, at least one of a main substrate, an attached circuit substrate, and a resin substrate such as polyimide used for electrically connecting them. In an electronic device composed of a flexible printed circuit board with copper wiring formed on the surface, a laminated board manufactured by accurately positioning the flexible printed circuit board and crimping it to the wiring ends of the main circuit board and the attached circuit board Is mentioned. That is, in this case, the laminate is a laminate in which the wiring end portions of the flexible printed circuit board and the main body substrate are bonded together by pressure bonding, or the wiring edge portions of the flexible printed circuit board and the circuit board are bonded together by pressure bonding. Laminated board. The laminated board has a mark formed of a part of the copper wiring and a separate material. The position of the mark is not particularly limited as long as it can be photographed by photographing means such as a CCD camera through the resin constituting the laminated plate. Here, the mark refers to a mark used to detect, position, or align the position of a laminated board, printed wiring board, or the like.

  In the laminated plate thus prepared, when the above-described mark is photographed by the photographing means through the resin, the position of the mark can be detected satisfactorily. And the position of the said mark can be detected in this way, and based on the position of the said detected mark, the positioning of the laminated board of surface-treated copper foil and a resin substrate can be performed favorably. Similarly, when a printed wiring board is used as the laminated board, the photographing means can detect the position of the mark well by such a positioning method, and the printed wiring board can be positioned more accurately.

Therefore, when one printed wiring board and another printed wiring board are connected, it is considered that the connection failure is reduced and the yield is improved. In addition, as a method of connecting one printed wiring board and another printed wiring board, connection via soldering or anisotropic conductive film (ACF), anisotropic conductive paste (Anisotropic Conductive Paste, A known connection method such as connection via ACP) or connection via a conductive adhesive can be used. In the present invention, the “printed wiring board” includes a printed wiring board, a printed circuit board, and a printed board on which components are mounted. Also, it is possible to manufacture a printed wiring board in which two or more printed wiring boards are connected by connecting two or more printed wiring boards according to the present invention, and at least one printed wiring board according to the present invention. One printed wiring board of the present invention or a printed wiring board not corresponding to the printed wiring board of the present invention can be connected. Moreover, you may manufacture the printed wiring board which connected two or more printed wiring boards using the surface-treated copper foil of this invention, and connected two or more printed wiring boards. Further, as a production of a printed wiring board in which two or more printed wiring boards are connected, at least one printed wiring board using the surface-treated copper foil of the present invention and another printed wiring board of the present invention or the printed circuit board of the present invention. You may include the process of connecting with the printed wiring board which does not correspond to a wiring board. And an electronic device can also be manufactured using these printed wiring boards.
In the present invention, “copper circuit” includes copper wiring. Furthermore, the printed wiring board of the present invention may be connected to a component to produce a printed wiring board. Further, at least one printed wiring board of the present invention is connected to another printed wiring board of the present invention or a printed wiring board not corresponding to the printed wiring board of the present invention. A printed wiring board in which two or more printed wiring boards are connected may be manufactured by connecting two or more printed wiring boards and components. Here, as “components”, connectors, LCDs (Liquid Crystal Display), electronic components such as glass substrates used in LCDs, ICs (Integrated Circuits), LSIs (Large scale integrated circuits), VLSIs (Very Large scale circuits). ), Electronic components including semiconductor integrated circuits such as ULSI (Ultra-Large Scale Integration) (for example, IC chips, LSI chips, VLSI chips, ULSI chips), components for shielding electronic circuits, and covers on printed wiring boards Examples include parts necessary for fixing.

The positioning method according to the embodiment of the present invention may include a step of moving a laminated board (including a laminated board of copper foil and a resin substrate and a printed wiring board). In the moving process, for example, it may be moved by a conveyor such as a belt conveyor or a chain conveyor, may be moved by a moving device provided with an arm mechanism, or may be moved by floating a laminated plate using gas. It may be moved by a moving means, a moving device or moving means (including a roller or a bearing) that moves a laminated plate by rotating an object such as a substantially cylindrical shape, a moving device or moving means that uses hydraulic pressure as a power source, Moving devices and moving means powered by air pressure, moving devices and moving means powered by motors, gantry moving linear guide stages, gantry moving air guide stages, stacked linear guide stages, linear motor drive stages, etc. It may be moved by a moving device or moving means having a stage. Moreover, you may perform the movement process by a well-known moving means. In the step of moving the laminated plate, the laminated plate can be moved for alignment. Then, it is considered that by performing alignment, connection failure is reduced and yield is improved when one printed wiring board is connected to another printed wiring board or components.
The positioning method according to the embodiment of the present invention may be used for a surface mounter or a chip mounter.
Moreover, the printed wiring board which has the circuit provided on the resin board and the said resin board may be sufficient as the laminated board of the surface treatment copper foil and the resin board which are positioned in this invention. In that case, the mark may be the circuit.

  In the present invention, “positioning” includes “detecting the position of a mark or an object”. In the present invention, “alignment” includes “after detecting the position of a mark or object, moving the mark or object to a predetermined position based on the detected position”.

As Examples 1 to 24 and Comparative Examples 1 to 13, various copper foils were prepared, and plating treatment was performed on one surface under the conditions described in Tables 1 to 8 as a roughening treatment.
After performing the above-mentioned roughening plating treatment, plating treatment for forming the following heat-resistant layer and rust-preventing layer is performed for Examples 1 to 13, 15 to 20, 22 to 24, and Comparative Examples 2, 4, and 7 to 10. went.
The conditions for forming the heat-resistant layer 1 are shown below.
Liquid composition: Nickel 5-20 g / L, cobalt 1-8 g / L
pH: 2-3
Liquid temperature: 40-60 degreeC
Current density: 5 to 20 A / dm ²
Coulomb amount: 10-20 As / dm ²
A heat-resistant layer 2 was formed on the copper foil provided with the heat-resistant layer 1. In Comparative Examples 3, 5, and 6, the rough plating treatment was not performed, and the heat-resistant layer 2 was directly formed on the prepared copper foil. The conditions for forming the heat-resistant layer 2 are shown below.
Liquid composition: nickel 2-30 g / L, zinc 2-30 g / L
pH: 3-4
Liquid temperature: 30-50 degreeC
Current density: 1 to ^{2 A} / dm ²
Coulomb amount: 1-2 As / dm ²
On the copper foil which gave the said heat-resistant layers 1 and 2, the antirust layer was further formed. The conditions for forming the rust preventive layer are shown below.
Liquid composition: potassium dichromate 1-10 g / L, zinc 0-5 g / L
pH: 3-4
Liquid temperature: 50-60 degreeC
Current density: 0 to ^{2 A} / dm ² (for immersion chromate treatment)
Coulomb amount: 0 to ^{2 As} / dm ² (for immersion chromate treatment)
On the copper foil which gave the said heat-resistant layers 1 and 2 and a rust prevention layer, the weathering layer was further formed. The formation conditions are shown below.
As silane coupling agents having amino groups, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane (Example 17), N-2- (aminoethyl) -3-aminopropyltriethoxysilane (implementation) Examples 1-13, 15, 16, 24), N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane (Example 18), 3-aminopropyltrimethoxysilane (Example 19), 3-amino Propyltriethoxysilane (Example 20), 3-triethoxysilyl-N- (1,3-dimethyl-butylidene) propylamine (Example 22), N-phenyl-3-aminopropyltrimethoxysilane (Example 23) ) Was applied and dried to form a weather resistant layer. These silane coupling agents can be used in combination of two or more.

In addition, the rolled copper foil was manufactured as follows. After manufacturing the copper ingot of the composition shown in Table 9 and performing hot rolling, annealing and cold rolling of a continuous annealing line at 300 to 800 ° C. were repeated to obtain a rolled sheet having a thickness of 1 to 2 mm. This rolled plate was annealed and recrystallized in a continuous annealing line at 300 to 800 ° C., and finally cold-rolled to the thickness shown in Table 9 to obtain a copper foil. “Tough pitch copper” in the “Type” column of Table 9 indicates tough pitch copper standardized in JIS H3100 C1100, and “Oxygen-free copper” indicates oxygen-free copper standardized in JIS H3100 C1020. “Tough pitch copper + Ag: 100 ppm” means that 100 mass ppm of Ag is added to tough pitch copper.
The electrolytic copper foil used was an electrolytic copper foil HLP foil manufactured by JX Nippon Mining & Metals. When electrolytic polishing or chemical polishing was performed, the plate thickness after electrolytic polishing or chemical polishing was described.
Table 9 shows the points of the copper foil preparation process before the surface treatment. “High gloss rolling” means that the final cold rolling (cold rolling after the final recrystallization annealing) was performed at the value of the oil film equivalent. “Normal rolling” means that the final cold rolling (cold rolling after the final recrystallization annealing) was performed at the oil film equivalent value described. “Chemical polishing” and “electropolishing” mean the following conditions.
“Chemical polishing” was performed using an etching solution of 1 to 3% by mass of H ₂ SO ₄ , 0.05 to 0.15% by mass of H ₂ O ₂ , and the remaining water, and the polishing time was 1 hour.
“Electropolishing” is a condition of phosphoric acid 67% + sulfuric acid 10% + water 23%, voltage 10 V / cm ² , and the time shown in Table 9 (when electropolishing for 10 seconds, the polishing amount is 1 to 2 μm. ).

Various evaluation was performed as follows about each sample of the Example and comparative example which were produced as mentioned above.
(1) Measurement of surface roughness (Rz);
Ten-point average roughness was measured on the roughened surface using a contact roughness meter Surfcorder SE-3C manufactured by Kosaka Laboratory Co., Ltd. in accordance with JIS B0601-1994. Measurement standard length 0.8mm, evaluation length 4mm, cut-off value 0.25mm, feed rate 0.1mm / sec. Perpendicular to rolling direction (in TD, in case of electrolytic copper foil, in foil passing direction) The measurement position was changed 10 times (perpendicularly), and the values for 10 measurements were obtained.
In addition, the surface roughness (Rz) was calculated | required similarly about the copper foil before surface treatment.

(2) Particle area ratio (A / B);
The surface area of the roughened particles was measured by a laser microscope. Using a laser microscope VK8500 manufactured by Keyence Co., Ltd., measuring the three-dimensional surface area A in an area B equivalent to 100 × 100 μm at a magnification of 2000 times the roughened surface (actual data: 9982.52 μm ² ), the three-dimensional surface area A ÷ Setting was performed by a method of setting a two-dimensional surface area B = area ratio (A / B).

(3) Glossiness;
Using Nippon Denshoku Industries Co., Ltd. gloss meter handy gloss meter PG-1 in accordance with JIS Z8741, rolling direction (MD, foil direction in the case of electrolytic copper foil) and direction perpendicular to the rolling direction (TD, In the case of an electrolytic copper foil, the roughened surface was measured at an incident angle of 60 degrees in a direction perpendicular to the direction of threading.
In addition, the glossiness was calculated | required similarly about the copper foil before surface treatment.

(4) The slope of the brightness curve;
The copper foil was bonded to both surfaces of a polyimide film with a thermosetting adhesive for lamination (thickness 50 μm, Upilex manufactured by Ube Industries), and the copper foil was removed by etching (ferric chloride aqueous solution) to prepare a sample film. Subsequently, a printed material on which a line-shaped black mark is printed is laid under the sample film, the printed material is photographed with a CCD camera through the sample film, and the observed line-shaped mark is observed on the image obtained by photographing. In the observation point-lightness graph created by measuring the lightness at each observation point along the direction perpendicular to the direction of extension, the inclination (angle) of the lightness curve that occurs from the end of the mark to the part where the mark is not drawn It was measured. FIG. 3 is a schematic diagram showing the configuration of the photographing apparatus used at this time and the method of measuring the inclination of the brightness curve. Further, ΔB and inclinations k1 and k2 were measured as shown in FIG. One pixel on the horizontal axis corresponds to a length of 10 μm. Then, the ratio of the length of one pixel to one gradation in the lightness curve graph is 3.5: 5 (the length of one pixel in the lightness curve graph: the length of one gradation in the lightness curve graph = 3. The values of k1 and k2 (°) were calculated in a lightness curve graph with 5 (mm): 5 (mm)).
The photographing device has a CCD camera, a stage (white) on which a polyimide substrate is placed with a marked paper underneath, an illumination power source that irradiates light onto the photographing portion of the polyimide substrate, and a paper with a mark to be photographed. A transporter (not shown) for transporting the evaluation polyimide substrate placed below onto the stage is provided. The main specifications of the camera are as follows:
・ Photographing device: Sheet inspection device Mujken manufactured by Nireco Corporation
CCD camera: 8192 pixels (160 MHz), 1024 gradation digital (10 bits)
・ Power supply for lighting: High frequency lighting power supply (power supply unit x 2)
・ Lighting: Fluorescent lamp (30W)
The slope (angle) of the lightness curve is an index indicating the rate of increase (or rate of decrease) in the portion corresponding to the vicinity of the mark end, and in FIG. 3, a predetermined curve in which the lightness is increased (or decreased). It is expressed by “tan ⁻¹ (increased or decreased brightness (y) / observation distance (x))” in the portion.
For the lightness shown in FIG. 3, 0 means “black”, lightness 255 means “white”, and the gray level from “black” to “white” (black and white shading, gray scale) Is divided into 256 gradations for display.

(5) Visibility (resin transparency);
The copper foil was laminated on both sides of a polyimide film with a thermosetting adhesive for lamination (thickness 50 μm, Ube Industries Upilex), and the copper foil was removed by etching (ferric chloride aqueous solution) to prepare a sample film. A printed material (black circle with a diameter of 6 cm) was attached to one surface of the obtained resin layer, and the visibility of the printed material was judged from the opposite surface through the resin layer. “◎” indicates that the outline of the black circle of the printed material is clear when the length is 90% or more of the circumference, and “Clear” indicates that the outline of the black circle is clear when the length is 80% or more and less than 90% of the circumference. “O” (passed above), a black circle with a clear outline of 0 to less than 80% of the circumference and a broken outline were evaluated as “x” (failed).

(6) Peel strength (adhesive strength);
Based on PC-TM-650, the normal peel strength was measured with a tensile tester Autograph 100, and a normal peel strength of 0.7 N / mm or more could be used for laminated substrate applications.

(7) Solder heat resistance evaluation;
The copper foil was bonded to both surfaces of a polyimide film with a thermosetting adhesive for laminating (thickness 50 μm, Upilex manufactured by Ube Industries). About the obtained double-sided laminated board, the test coupon based on JISC6471 was created. The prepared test coupon was exposed to high temperature and high humidity of 85 ° C. and 85% RH for 48 hours, and then floated in a solder bath at 300 ° C. to evaluate solder heat resistance. After the solder heat resistance test, at the interface between the copper foil roughening surface and the polyimide resin adhesion surface, the area where the interface discolored due to blistering in an area of 5% or more of the copper foil area in the test coupon is x (failed), area When the color change was less than 5%, the case was evaluated as ◯, and the case where no color change occurred was evaluated as ◎.

(8) Yield;
The copper foil was bonded to both sides of a polyimide film with a thermosetting adhesive for lamination (thickness 50 μm, Ube Industries Upilex), the copper foil was etched (ferric chloride aqueous solution), and L / S was 30 μm / 30 μm. An FPC with a circuit width was created. After that, an attempt was made to detect a 20 μm × 20 μm square mark with a CCD camera through polyimide. “◎” when 9 times or more out of 10 times can be detected, “◯” when 7 to 8 times can be detected, “△” when 6 times can be detected, and when 5 times or less can be detected. Is “×”.

(9) Circuit shape by etching (fine pattern characteristics);
The copper foil was bonded to both surfaces of a polyimide film with a thermosetting adhesive for laminating (thickness 50 μm, Upilex manufactured by Ube Industries). In order to perform fine pattern circuit formation, it is necessary to make the copper foil thickness the same, and here, a thickness of 12 μm copper foil was used as a reference. That is, when the thickness was thicker than 12 μm, the thickness was reduced to 12 μm by electrolytic polishing. On the other hand, when the thickness was thinner than 12 μm, the thickness was increased to 12 μm by copper plating. For one side of the resulting double-sided laminate, the fine pattern circuit is printed by the photosensitive resist coating and exposure process on the copper foil glossy side of the laminate, and unnecessary portions of the copper foil are etched under the following conditions, A fine pattern circuit having L / S = 20/20 μm was formed. Here, the circuit width was set such that the bottom width of the circuit cross section was 20 μm.
(Etching conditions)
Equipment: Spray type small etching equipment Spray pressure: 0.2 MPa
Etching solution: Ferric chloride aqueous solution (specific gravity 40 Baume)
Liquid temperature: 50 ° C
After forming the fine pattern circuit, the photosensitive resist film was peeled off by dipping in a 45 ° C. NaOH aqueous solution for 1 minute.

(10) Calculation of etching factor (Ef);
The fine pattern circuit sample obtained above is observed from the top of the circuit at a magnification of 2000 using a scanning electron micrograph S4700 manufactured by Hitachi High-Technologies Corporation. The top width (Wa) of the top of the circuit and the bottom of the circuit The bottom width (Wb) of was measured. The copper foil thickness (T) was 12 μm. The etching factor (Ef) was calculated by the following formula.
Etching factor (Ef) = (2 × T) / (Wb−Wa)

(11) Measurement of transmission loss;
For each sample having a thickness of 18 μm, after bonding with a commercially available liquid crystal polymer resin (Vecstar CTZ-50 μm manufactured by Kuraray Co., Ltd.), a microstrip line is formed by etching so that the characteristic impedance is 50Ω. The transmission coefficient was measured using a network analyzer HP8720C, and the transmission loss at a frequency of 20 GHz and a frequency of 40 GHz was determined. As an evaluation of transmission loss at a frequency of 20 GHz, 未 満 less than 3.7 dB / 10 cm, ◎ 3.7 dB / 10 cm or more and less than 4.1 dB / 10 cm, 、 ４ 4.1 dB / 10 cm or more and less than 5.0 dB / 10 cm, △, 5.0 dB / 10 cm or more was defined as x.
The conditions and evaluation of each test are shown in Tables 1-12.

(Evaluation results)
In Examples 1 to 24, visibility, peel strength, solder heat resistance evaluation and yield were all good.
Comparative Examples 1-2, 4, 7-11, and 13 had poor visibility because one or more values of ΔB, ΔB / ΔB (PI), and k1 were out of the scope of the present invention.
In Comparative Examples 3, 5, 6, and 12, the visibility was excellent, but since the value of k1 exceeded 87 °, the substrate adhesion was poor. In Comparative Examples 1 to 13, the solder heat resistance evaluation was poor.
FIG. 4 shows (a) Comparative Example 1, (b) Comparative Example 2, (c) Comparative Example 3, (d) Comparative Example 4, (e) Example 1, and (f) in the Rz evaluation. The SEM observation photograph of the copper foil surface of Example 2 is shown, respectively.

Claims (21)

A surface-treated copper foil in which roughened particles are formed by roughening treatment on at least one surface,
Etching after bonding the copper foil to both surfaces of a substrate having a thickness of 50 μm from the surface of the roughening treatment (polyimide having the following ΔB (PI) of 20 to 33 for the polyimide before being bonded to the copper foil). To remove the copper foil on both sides,
When a printed matter on which a line-shaped mark is printed is laid under the exposed polyimide substrate, and the printed matter is photographed with a CCD camera through the polyimide substrate,
For the image obtained by the photographing, an observation point-brightness graph prepared by measuring the brightness of each observation point along the direction perpendicular to the direction in which the observed line-shaped mark extends,
A difference ΔB (ΔB = Bt−Bb) between a top average value Bt and a bottom average value Bb of a brightness curve generated from an end portion of the mark to a portion where the mark is not drawn is 20 or more,
The ratio of ΔB / ΔB (PI) is 0.7 or more,
A surface-treated copper foil in which the slope (angle) k1 of the lightness curve in a depth range of 0.4 ΔB to 0.6 ΔB with respect to Bt is 65 ° or more and 87 ° or less.   In the observation point-lightness graph prepared from the image obtained by the photographing, the slope (angle) k2 of the lightness curve in the depth range from the intersection of the lightness curve and Bt to 0.1 ΔB with reference to Bt is 30 °. The surface-treated copper foil of Claim 1 used as the above.   The surface-treated copper foil according to claim 1 or 2, wherein ΔB is 28 or more in an observation point-lightness graph produced from an image obtained by the photographing.   The surface-treated copper foil as described in any one of Claims 1-3 from which the inclination (angle) k1 of the said brightness curve becomes 75 to 87 degree.   The surface-treated copper foil according to any one of claims 2 to 4, wherein an inclination (angle) k2 of the lightness curve is 40 ° or more. The TD average roughness Rz of the roughened surface is 0.20 to 0.80 μm, the 60 degree gloss of MD of the roughened surface is 76 to 350%,
The ratio A / B between the surface area A of the roughened particles and the area B obtained when the roughened particles are viewed in plan from the copper foil surface side is 1.90 to 2.40. The surface-treated copper foil as described in any one of these.   The surface-treated copper foil according to claim 6, wherein the MD has a 60-degree glossiness of 90 to 250%.   The surface-treated copper foil according to claim 6 or 7, wherein the average roughness Rz of the TD is 0.30 to 0.60 µm.   Said A / B is 2.00-2.20, The surface-treated copper foil as described in any one of Claims 6-8.   The ratio C (C = (60 degree gloss of MD) / (60 degree gloss of TD)) of the 60 degree gloss of MD and 60 degree gloss of TD on the roughened surface is 0.80 to 1. The surface-treated copper foil according to any one of claims 6 to 9, which is 40.   The ratio C (C = (60 ° gloss of MD) / (60 ° gloss of TD)) of the 60 ° gloss of MD and 60 ° gloss of TD on the roughened surface is 0.90 to 1. The surface-treated copper foil according to claim 10, which is 35.   The laminated board comprised by laminating | stacking the surface treatment copper foil and resin substrate as described in any one of Claims 1-11.   The printed wiring board using the surface-treated copper foil as described in any one of Claims 1-11.   An electronic device using the printed wiring board according to claim 13.   A method of manufacturing a printed wiring board in which two or more printed wiring boards are connected by connecting two or more printed wiring boards according to claim 13.   Connecting at least one printed wiring board according to claim 13 to another printed wiring board according to claim 13 or a printed wiring board not corresponding to the printed wiring board according to claim 13; A method of manufacturing a printed wiring board in which two or more printed wiring boards are connected.   An electronic device using one or more printed wiring boards in which two or more printed wiring boards according to claim 15 are connected.   An electronic device using one or more printed wiring boards to which two or more printed wiring boards according to claim 16 are connected.   An electronic apparatus using at least one printed wiring board to which at least one printed wiring board according to claim 15 is connected.   A method for manufacturing a printed wiring board, comprising at least a step of connecting the printed wiring board according to claim 13 and a component. Connecting at least one printed wiring board according to claim 13 to another printed wiring board according to claim 13 or a printed wiring board not corresponding to the printed wiring board according to claim 13, and
A printed wiring board having two or more printed wiring boards connected, comprising at least a step of connecting a printed wiring board according to claim 13 or two or more printed wiring boards according to claim 16 and a component. A method of manufacturing a wiring board.

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