JPH07235744A - Increased high-temperature elongation copper foil for printing circuit and its manufacture - Google Patents

Abstract

PURPOSE:To develop a high-temperature elongation copper foil for printing circuits, which is less liable to break on a copper-clad laminate. CONSTITUTION:The copper foil has a glossy surface having a Vickers hardness of 65 or more on its glossy surface side after the manufacture of a copper-clad laminate, and the roughness on its glossy side is decreased to less than a central line average roughness of 0.15mum. Intrusion of foreign matters into the copper foil is suppressed by raising the surface hardness of the glossy surface after the manufacture of a copper-clad laminate, and catching foreign matter is lessened and mutual catching by the peaks of the glossy surface of the copper foil is also lessened. For increasing the hardness on the glossy side after the manufacture of a copper-clad laminate, there are methods of fitting a layer hard to recrystallize on the glossy side, performing alloy printing, performing plating so as to make an alloy with copper by diffusion by heat generated at the time of the manufacture of the copper-clad laminate, etc. For decreasing the roughness on the glossy side, there are methods of fining the polishing of a drum for manufacturing raw foil, plating copper or zinc on the glossy side of performing etching, etc.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-temperature and high-strength copper foil for printed circuits and a method for manufacturing the same, and more particularly, to prevent breakage of the copper foil during and after the manufacturing process of a copper clad laminate. , High-temperature stretched copper foil for printed circuits with increased hardness after production of the copper-clad laminate on the glossy side, and also reduced surface roughness in addition to the smoothness after production of the copper-clad laminate The present invention relates to an enhanced high temperature stretched copper foil for printed circuits and a method for manufacturing the same.

[0002]

2. Description of the Related Art Copper and copper alloy foils (hereinafter referred to as copper foils)
Contributes greatly to the development of the electrical and electronic related industries,
In particular, it is indispensable as a printed circuit material. Copper foil for printed circuits is generally manufactured by laminating and adhering to a substrate such as a synthetic resin board or a film via an adhesive under high temperature and high pressure without using an adhesive to produce a copper clad laminate, and then the purpose After printing the necessary circuit to form the circuit, an etching process for removing unnecessary parts is performed. Finally, the required elements are soldered to form various printed circuit boards for electronic devices. Quality requirements for a copper foil for a printed circuit board are different between a surface (roughened surface) bonded to a resin substrate and a non-bonded surface (glossy surface), and many methods have been proposed for each.

As a method of manufacturing a copper clad laminate, a hot pressing method or a continuous method has recently been adopted. For example, taking the production of a paper-based phenolic resin copper-clad laminate by a hot pressing method as an example, a prepreg is produced by synthesizing a phenolic resin, impregnating a paper-based resin with a phenolic resin and drying, and finally, A predetermined number of prepregs and copper foil are combined, thermocompression molding is performed by a multi-stage press, stripping and edge cutting are performed, and the next step is sent. In the case of the continuous method, single-sided copper-clad laminates and double-sided copper-clad laminates are manufactured. For example, in the case of a paper-based polyester resin copper-clad laminate, a base paper is fed out from a plurality of roll-shaped base papers, and a plurality of resin-impregnated papers are laminated by a roll pair through a paper treatment and a resin impregnation step, respectively. It Next, the copper foil that has undergone the adhesive application step, and in the case of one side, the copper foil and the carrier are laminated. The product thickness is controlled in this laminating and laminating process. Next, it is sent to a curing furnace, where a curing reaction of the resin occurs and the resin is cured. After curing, the product is subjected to regular length cutting, after-curing and polishing of the end face, and further visual inspection and characteristic inspection to obtain a product. Roll-shaped raw materials such as base paper, copper foil and carrier are successively connected to new rolls and continuously operated. The difference between one side and both sides is that in the case of one side,
The carrier film is fed from below, the carrier is peeled off after resin curing, and wound up, whereas in the case of both sides, the copper foil is also fed from below through the adhesive application step, and the other steps are also on one side. Both sides are the same. In addition, the glass-epoxy resin substrate and the like are manufactured in the same process.

During the production of a copper-clad laminate, strain inside the insulating layer due to movement of the resin such as curing shrinkage when the resin-impregnated base material serves as an insulating layer or thermal expansion of the resin, and the accompanying distortion of the printed circuit board. It is known that a copper foil having a high elongation at high temperature may be used to suppress the occurrence of warpage and twist.
For example, according to the description in JP-A-5-243698,
"The metal foil used in the conventional method for continuously producing a metal foil-clad laminate has a small elongation at high temperature. For example, the elongation at 180 ° C is about 1 to 8%. When the material becomes an insulating layer, it cannot follow the movement of the resin such as curing shrinkage and thermal expansion of the resin, so that distortion easily occurs inside the insulating layer, which causes the metal foil-clad laminate to warp or twist. In particular, in a metal foil-clad laminated sheet that is continuously manufactured using a long metal foil, the metal foil is always pulled and integrated during the manufacturing process so that the elongation is small and the relaxation margin is small, so the warpage is more remarkable. In addition, in the case of a double-sided metal foil-clad laminate,
If only one side of the metal foil is removed, the warp due to the distortion of the insulating layer and the twist becomes large. Further, due to the strain inside the insulating layer, there is a problem that the dimensional change rate becomes large when the metal foil is removed. "Providing a metal foil-clad laminate and a method for producing the same, which is capable of producing a metal foil-clad laminate having a small amount of warp and twist, which is further excellent in dimensional stability." As 150
It describes to use a metal foil having an elongation of 10 to 50% at a temperature of ℃ to 200 ℃.

In the case of copper foil, tensile at 180 ° C .: Tensile strength 10
-20 kg / mm ² , elongation: 10-50%, for example S
A high temperature stretched copper foil called TCS foil (manufactured by Nikko Gould Foil Co., Ltd.) has been obtained.

[0006]

The high-temperature and high-strength copper foil of this type is recrystallized by the heat applied during the production of the copper-clad laminate, and its hardness is lowered. Therefore, in the conventional high-temperature and high-strength copper foil for printed circuits, after the copper-clad laminate is manufactured, when the copper-clad laminate moves due to vibration during loading and conveying, foreign matter such as resin powder generated during cutting is mixed. Moreover, the surface of the copper foil is easily caught in the copper foil and is likely to break into the copper foil. Further, in the case of a double-sided copper-clad laminate, similar tearing of the copper foil was likely to occur even if the mountains on the glossy side were caught.

The present invention aims to solve the above-mentioned drawbacks. That is, an object of the present invention is to develop a high-temperature stretchable copper foil for a printed circuit, which can suppress the occurrence of breakage of the copper foil after manufacturing the copper-clad laminate.

[0008]

Means for Solving the Problems As a result of intensive studies made by the present inventors in order to solve the above-mentioned drawbacks, as a result, the surface exposed after the production of the copper-clad laminate, that is, the surface after the production of the copper-clad laminate on the gloss side By increasing the hardness to a Vickers hardness of 65 or more, it is possible to prevent the intrusion of foreign matter such as mixed resin powder,
It is possible to prevent the copper foil from breaking, and at first glance it looks smooth, but there is still roughness on the surface, which is the cause of foreign matter such as resin powder being caught or between the mountains on the glossy side. Also, the roughness on the glossy side of the high-temperature and high-strength copper foil is expressed by the center line average roughness Ra, Ra: 0.15.
It has been found that such a catch can be drastically reduced and the occurrence of tearing of the copper foil can be suppressed by reducing the thickness to less than or equal to μm. Based on this finding, the present invention
(1) High-temperature and high-strength copper foil, wherein the high-temperature and high-strength copper foil is provided with a glossy surface having a Vickers hardness of 65 or more on the glossy side after the copper-clad laminate is manufactured. In the stretched copper foil and (2) high-temperature and high-temperature stretched copper foil, the high-temperature and high-strength stretched copper foil has a roughness on a glossy surface side as a center line average roughness Ra.
The printed circuit is characterized by having a Ra of 0.15 μm or less to make it smooth, and at the same time, having a glossy surface with a Vickers hardness of 65 or more on the glossy side after the production of the copper clad laminate. Provide high temperature stretched copper foil. Furthermore,
The present invention also provides a layer on the glossy side of the high-temperature stretched copper foil that is difficult to recrystallize due to heat during the production of the copper-clad laminate, or performs alloy plating on the glossy side of the high-temperature stretched copper foil, or The Vickers hardness on the glossy side of the high-temperature stretched copper foil is 65 after the copper-clad laminate is produced by plating the glossy side of the high-temperature stretched copper foil so that it is diffused by heat during the production of the copper-clad laminate to form an alloy with copper.
Also provided is a method for producing a high-temperature stretched copper foil for a printed circuit, which has a glossy surface as described above.

[0009]

[Function] Since the surface hardness of the high-temperature-stretched copper foil for printed circuits on the glossy side of the copper-clad laminate is increased to 65 or more in terms of Vickers hardness, foreign matter such as resin powder is prevented from penetrating into the copper foil. The occurrence of breakage of the copper foil is suppressed, and further, the roughness on the glossy side of the high-temperature stretched copper foil for printed circuits is expressed by the center line average roughness Ra, and Ra is reduced to 0.15 μm or less. Even if foreign matter such as resin powder enters, it is less likely to get caught and acts like a roller, making it difficult to bite into the copper foil. In addition, there is less chance of catching between the shiny surfaces of the copper foil. Therefore, the occurrence of breakage of the copper foil is suppressed. To increase the hardness of the glossy side after the copper-clad laminate is manufactured, attach a layer on the glossy side that is not easily recrystallized by the heat during the production of the copper-clad laminate, or apply alloy plating to the glossy side. There are several methods, including plating the side to diffuse with the heat during manufacture of the copper clad laminate to form an alloy with copper. In addition, in order to reduce the roughness of the glossy side of the printed circuit copper foil, the polishing of the electrolytic copper foil raw foil manufacturing drum should be done finely, the glossy side should be plated, the glossy side should be etched, etc. There are several ways to include.

[0010]

DETAILED DESCRIPTION OF THE INVENTION The copper foil used in the present invention is a high temperature stretched copper foil. High-temperature stretched copper foil is 180
Tensile strength at 10 ° C: Tensile strength 10 to ²⁰ kg / mm ² , elongation: 10
It is characterized by ˜50%, and examples thereof include STCS foil manufactured by Nikko Gould Foil Co., Ltd.

Although the present invention pertains to the glossy surface of the high-temperature and high-strength copper foil, the roughened surface of the copper foil will be described for reference. Usually, on the surface of the copper foil that is bonded to the resin substrate, that is, the roughened surface, for the purpose of improving the peeling strength of the copper foil after lamination, the surface of the copper foil after degreasing, for example, is made of copper Roughening treatment is performed to perform electrodeposition in the form of strips. Such copper kinky electrodeposition is easily brought about by so-called burn electrodeposition. As an example of the copper roughening treatment, for example, the following conditions can be adopted. [Doaraka processing conditions] _{Cu: 5~50g / l H 2 SO} 4: 10~100g / l As: 0.01~5g / l liquid temperature: room temperature _{~50 ℃ D k: 5~80A / dm} 2 hours : 1 to 30 seconds

After the roughening treatment, thin copper plating is performed as a cover layer for preventing the particles from falling off. For example, the following conditions can be adopted. [Cover thin copper layer plating conditions] _{Cu: 30~100g / l H 2 SO} 4: 10~200g / l liquid temperature: room temperature _{~75 ℃ D k: 5~60A / dm} 2 Time: 1-30 seconds

It is preferable to perform a treatment for forming a single metal layer or an alloy layer of one or more selected from Cu, Cr, Ni, Fe, Co and Zn on the roughened surface. Examples of alloy plating include Cu-Ni and Cu-C.
o, Cu-Ni-Co, Cu-Zn and others (for details, see Japanese Examined Patent Publication No. 56-9028, Japanese Patent Laid-Open No. Sho 5-9).
4-13971, JP-A-2-292895, JP-A-2-292894, JP-B-51-35711, JP-B-54-6701 and the like). Such treat treatment serves as a determinant and barrier to the final properties of the copper foil.

Now, in the glossy surface to which the present invention relates, first, a raw foil which is hard to be recrystallized during the production of the copper-clad laminate is produced by a treatment for increasing the hardness of the glossy surface after the production of the copper-clad laminate. It is foiled. In order to increase or maintain the Vickers hardness of 65 or more, preferably 70 or more, particularly 75 or more, on the glossy side after the production of the copper-clad laminate, (1) alloy plating is applied to the glossy side ( 2) The shiny side is plated to form an alloy with copper by diffusing due to the heat during the production of the copper clad laminate, or (3) The gloss side is less likely to be recrystallized by the heat during the production of the copper clad laminate. Several methods are possible, such as layering. Here are specific examples of each:

(1) When alloy plating is applied: Plating metal: Alloy plating such as Cu-Zn and Cu-Ni is applied. An example of Cu-Zn plating conditions is shown below. [Cu-Zn plating conditions] Cu: 40 to 80 g / l Zn: 0.5 to 5.5 g / l NaCN: 10 to 30 g / l NaOH: 40 to 100 g / l Temperature: 60 to 80 ° C _Dk : 1 to 10 A / dm ² hours: 1 to 10 seconds

(2) When plating is performed so as to diffuse by heat to form an alloy with copper: Zn, S as plating metals
n, Zn-Ni, Zn-Co, etc. are plated. Specific examples of plating conditions in the case of Zn plating are given below: [Zn plating] Zn: 15 to 70 g / l pH: 2.5 to 4.5 Temperature: 40 to 60 ° C. _Dk : 0.05 to 2 A / dm ² hours: 1 to 10 seconds

(3) Add a layer that is not easily recrystallized. For example, an anode is added in the initial stage of the raw foil forming process to form a low D _k foil, and then the operation is performed under normal operating conditions. Since the electrodeposition stress is low, an electrodeposition film that is difficult to recrystallize is formed.

Further, if necessary, a surface roughness reducing treatment for further improving the smoothness of the glossy surface may be performed before the plating for increasing the hardness after the production of the copper-clad laminate or after the raw foil making. Can be given. To reduce the catching and suppress the occurrence of tearing of the copper foil, the center line average roughness Ra:
It is necessary to reduce the thickness to 0.15 μm or less. This is done, for example, by copper plating or zinc plating or by etching. Examples of conditions for copper plating and zinc plating are given below. [Cu plating conditions] _{Cu: 30~100g / l H 2 SO} 4: 10~200g / l Temperature: room temperature _{~75 ℃ D k: 0.5~60A / dm} 2 Time: 1-30 sec [Zn plating conditions] Zn: 15 to 70 g / l pH: 2.5 to 4.5 g / l Temperature: 40 to 60 ° C. _Dk : 0.05 to ^{2 A} / dm ² hours: 1 to 10 seconds Adhesion amount is usually 0.01 to 20 mg / Dm ² , preferably 0.05 to 10 mg / dm ² , especially 0.5 to 5 mg /
dm ² . By this copper plating, the pits in the range of 0.1 to 0.3 μm scattered on the original shiny surface of the copper foil are completely disappeared, and the entire surface is covered with fine copper or zinc produced by the plating operation. It was confirmed by a scanning electron microscope (SEM) image at a magnification of 000.

Etching is also useful as a surface roughness reducing treatment for further improving the smoothness of the glossy surface. In this etching, the kind of etching bath, method, etc. are not particularly limited. The etching method is roughly classified into a dry method (blasting, ion irradiation) and a wet method (chemical method, electrochemical method), but chemical etching is the most convenient in terms of accuracy and economy. The type of etching bath is also not particularly limited, but an ammonium persulfate aqueous solution, a sulfuric acid-hydrogen peroxide aqueous solution, and the like, which are well known as etching solutions for copper materials and the like, are suitable. The etching amount is
It suffices if sufficient smoothness can be created, and it depends on the concentration of the etching solution, the bath temperature, the time, the stirring state, and the like. In general,
An etching amount of 0.01 to 2.5 μm is sufficient. The concentration of ammonium persulfate, bath temperature, time, and stirring conditions for this purpose are not uniquely determined, but the concentration of ammonium persulfate: 1
The etching amount was 0.0 under the conditions of 0 g / l, bath temperature: 25 ° C., linear liquid stirring speed: 1 m / sec, and etching time: 5 sec.
It becomes 3 μm. The etching solution is H ₂ O ₂ / H ₂ SO ₄ /
When the H ₂ O ratio (wt%) = 20.7 / 2.6 / 76.7, good results were obtained with an etching amount of about 2 μm.

In addition, it is recommended to finely grind the drum on which copper is electrodeposited during the production of copper foil. By changing the normal # 400 polishing belt finish to the # 1000 polishing belt finish, the surface of the high-temperature stretched copper foil can be smoothed.

It is also possible to achieve smoothing of the glossy surface at the same time by adjusting the electrolytic conditions during the plating for increasing the hardness of the glossy surface after the copper clad laminate is manufactured.

After that, a heat resistant oxidation treatment is applied if necessary. For the heat resistant oxidation treatment, any known method can be used. For example, Zn plating is a typical example. The electrolysis conditions are listed below. [Zn plating conditions] _{ZnSO 4 · 7H 2 O: 50~350g} / l pH ( sulfate): 2.5 to 4.5 Liquid _{temperature: 40~60 ℃ D k: 0.05~0.4A /} dm 2 hours : 10 to 30 seconds The Zn deposition amount is generally 15 to 1500 μg / dm ² , and preferably 15 to 400 μg / dm ² .

In addition to the above, thermal oxidation resistance (discoloration such as oxidation under the conditions of 100 ° C. or more × 30 minutes, preferably 200 ° C. or more × 30 minutes, particularly preferably 240 ° C. or more × 30 minutes in the atmosphere is prevented. Zn and Ni, Co,
A Zn alloy plating treatment of one or more kinds of metals selected from V, W, Mo, Sn, Cr and the like has been proposed and achieved.

Taking the Zn-Ni alloy treatment as an example, this preferably uses a Zn-Ni electroplating bath, preferably of a composition of 50-97 wt% Zn and 3-50 wt% Ni. Zn-Ni alloy layer 100-500μ
It is carried out so as to form a very thin film with an adhesion amount of g / dm ² . If the amount of Ni is less than 3% by weight, the required improvement in thermal oxidation resistance cannot be obtained. On the other hand, when the amount of Ni exceeds 50% by weight, the solder wettability deteriorates and the thermal oxidation resistance also deteriorates. Adhesion amount of Zn-Ni alloy layer is 100 μg / dm
^If it is less than ² , the improvement of the thermal oxidation resistance cannot be obtained. The other 50
When it exceeds 0 μg / dm ² , conductivity is deteriorated due to diffusion of Zn and the like. The Zn-Ni alloy layer enhances the thermal oxidation resistance of the glossy surface of the copper foil and does not impair other properties such as solder wettability and resist adhesion. The adhered amount is made thin as described above so that the appearance is not so different from the copper color. The same applies to the Zn-Co alloy treatment.

Compositions and examples of conditions of the Zn-Ni plating bath and the Zn-Co plating bath are as follows: [Zn-Ni (or Zn-Co) plating bath conditions] Zn: 5 to 50 g / l Ni (or Co): 1 to 50 g / l pH: 2.5 to 4 Temperature: 30 to 60 ° C. Current density: 0.5 to 5 A / dm ² Plating time: 0.1 to 10 seconds

Thereafter, a Cr-based rust preventive treatment is applied to the heat-resistant oxidation-treated layer or the glossy surface without the heat-resistant oxidation-treated layer. The Cr-based anticorrosion layer is formed by (1) a single film treatment of chromium oxide, (2) mixed film treatment of chromium oxide and zinc and / or zinc oxide, or (3) a combination thereof. This is a rust preventive layer mainly composed of chromium oxide.

Regarding the single coating of chromium oxide,
Either immersion chromate or electrolytic chromate may be used. When weather resistance is required, electrolytic chromate is preferable. The conditions of immersion chromate or electrolytic chromate follow the conditions established in the art. For example, examples of conditions for immersion chromate and electrolytic chromate treatment are as follows: (A) Immersion chromate treatment: K ₂ Cr ₂ O ₇ : 0.5 to 1.5 g / l pH: 1.4 to 5.0 Temperature: 20 to 60 ° C. Time: 3 to 10 seconds (B) Electrolytic chromate treatment: K ₂ Cr ₂ O ₇ : 0.2 to 20 g / l (Na ₂ Cr ₂ O ₇ , CrO ₃ ) acid: phosphoric acid, sulfuric acid , Organic acid pH: 1.0 to 3.5 Liquid temperature: 20 to 40 ° C. D _k : 0.1 to 0.5 A / dm
² hours: 10 to 60 seconds Cr adhesion amount is 50 μg / dm ² or less, preferably 15
˜30 μg / dm ² .

The treatment of a mixture of chromium oxide and zinc / zinc oxide is carried out by electroplating zinc or zinc oxide and chromium oxide by electroplating using a plating bath containing zinc salt or zinc oxide and chromate. This is a treatment for coating the rust preventive layer of the zinc-chromium group mixture, which is called electrolytic zinc-chromium treatment. The plating bath is typically K ₂ Cr ₂ O ₇ ,
At least one dichromate such as Na ₂ Cr ₂ O ₇ or CrO ₃ and a water-soluble zinc salt such as ZnO or ZnSO
₄ - at least one 7H ₂ O, etc., a mixed aqueous solution of alkali hydroxide is used. Typical plating bath compositions and examples of electrolysis conditions are as follows: (C) Electrolytic zinc / chromium treatment K ₂ Cr ₂ O ₇ (Na ₂ Cr ₂ O ₇ or CrO ₃ ): 2 to 10 g / l NaOH or KOH: 10 to 50 g / l ZnO or _{ZnSO 4 · 7H 2 O: 0.05~10g} / l pH: 7~13 bath temperature: 20 to 80 ° C. current density: 0.05~5A / dm ² Time: 5 30 seconds Anode: Pt-Ti plate, stainless steel plate, etc. Chromium oxide is required to have a chromium amount of 15 μg / dm ² or more, and zinc is required to have a coating amount of 30 μg / dm ² or more. The rough surface side and the glossy surface side may have different thicknesses.
Such rust prevention method is disclosed in Japanese Examined Patent Publication Sho 58-7077, 61-3.
3908, 62-14040 and the like. Combinations of chromium oxide alone coating and chromium oxide and zinc / zinc oxide mixture coating are also effective.

Finally, if necessary, a silane treatment for applying a silane coupling agent to at least the roughened surface of the rust-preventive layer is performed for the main purpose of improving the adhesive force between the copper foil and the resin substrate. The coating method may be spraying of a silane coupling agent solution, coating with a coater, dipping, pouring, or the like. For example, Japanese Examined Patent Publication No. 60-15654 describes that the adhesion between the copper foil and the resin substrate is improved by subjecting the rough surface side of the copper foil to a chromate treatment and then a silane coupling agent treatment. . For details, refer to this.

Inorganic fibers such as glass, paper and the like are used as the base material for producing the copper clad laminate, and phenol resin, epoxy resin, polyimide resin, unsaturated polyester resin and the like are used as the impregnating resin. . As mentioned at the beginning, the hot press method and the recent continuous method have been adopted as the method for producing a copper clad laminate. For example, in the case of producing a paper-based phenolic resin copper-clad laminate by a hot pressing method, a prepreg is produced by impregnating a paper-based phenolic resin and drying, and combining a predetermined amount of prepreg and a copper foil, Alternately combined with stainless steel mirror plate, apply cushioning material to the outside of the plate and insert it between the hot plates of the multi-stage press to perform thermo-compression molding. The pressing conditions are about 160 ° C x 100-150 for phenol resin.
kg / cm ² , and in the case of an epoxy resin or a polyimide resin, it is about 180 to 260 ° C. × 25 to 80 kg / cm ² . After heating, it is cooled, and then the plate is removed and the edges are trimmed. In the case of the continuous method, single-sided copper-clad laminates and double-sided copper-clad laminates are manufactured. For example, in the case of a paper-based polyester resin copper-clad laminate, a base paper is fed out from a plurality of roll-shaped base papers, and a plurality of resin-impregnated papers are laminated by a roll pair through a paper treatment and a resin impregnation step, respectively. It Next, the copper foil that has undergone the adhesive application step, and in the case of one side, the copper foil and the carrier are laminated. The product thickness is controlled in this laminating and laminating process. Next, it is sent to a curing oven to cure the resin. After curing the resin, the carrier is peeled off and wound up. After curing, the product is subjected to fixed length cutting, after-curing and polishing of the end face, and then a product after a certain amount of inspection is obtained. In the case of both sides, the copper foil is fed from the lower side through the adhesive applying step and is treated in the same manner. Other, glass-
Epoxy resin substrates and the like are manufactured in the same process. The curing temperature and curing time of the long strip-shaped laminate can be selected depending on the type of resin, but the curing is pressureless to 20 kg / cm ² .

According to the present invention, the copper-clad laminate thus obtained is provided with a layer which is hard to be recrystallized by heat during the production of the copper-clad laminate, or a high-temperature stretched copper foil is provided on the glossy side of the high-temperature stretched copper foil. The shiny side of the foil is alloy-plated, or the shiny side of the high-temperature and high-strength copper foil is plated to form an alloy with copper by diffusing due to the heat generated during the production of the copper-clad laminate. The Vickers hardness on the glossy surface side after the production of the stretched laminated plate is 65 or more, and, together with the smoothness of the glossy surface, the copper foil is unlikely to break during subsequent handling.

[0032]

EXAMPLES The present invention will be described in more detail with reference to Examples and Comparative Examples. The method of evaluating the printed circuit boards obtained in each of the examples and comparative examples is as follows. 1. Hardness measuring device: AKASHI MVK-E Hardness
Tester Load: 25 g Crimping: 15 seconds Average of n = 3 1. Surface roughness measurement device: roughness meter: made by Kosaka; universal surface shape measuring machine (SE3
C) 3. Breaking of copper foil Prepare substrates of 8 cm × 8 cm and 9 cm × 8 cm (hereinafter referred to as substrate A and substrate B, respectively), fix the substrate A below, and place the substrate B with a string on it. in addition,
Place a 15 kg weight. After that, the substrate B is pulled by 50 mm at a constant speed of 50 mm / sec. At this time, the sum of the number of breakages generated in the substrate A and the substrate B (8 cm × 8 cm portion which was in contact at the beginning) is measured.

(Example 1) Cu: 65 g / l, Zn: 4.5 g / l, Na on a glossy surface of a high-temperature and high-strength copper foil (STCS foil: manufactured by Nikko Gould Foil Co., Ltd.) having a thickness of 18 μm
CN: 12 g / l, NaOH: 70 g / l, temperature: 75
Electrolysis was performed at a current density of 8 A / dm ² for 6.3 seconds using an electrolytic solution at a temperature of ℃, and Cu-Zn plating having a thickness of about 0.1 μm was applied. Then, CrO ₃ on the Cu-Zn-plated: 5g
_{/ L, ZnSO 4 · 7H 2} O: 5g / l, NaOH: 2
Electrolysis was carried out for 12 seconds at a current density of 0.6 A / dm ² using an electrolytic zinc / chromium rust preventive solution of 0 g / l, pH = 10, temperature: 60 ° C. This copper foil is heat-treated at 180 ° C. for 30 minutes to adhere it to a glass-epoxy resin substrate, and after manufacturing a copper-clad laminate, the hardness of the glossy surface of the copper foil is measured and the copper foil breakage is evaluated. It was The results are shown in Table 1.

Comparative Example The same procedure as in Example 1 was carried out except that the Cu—Zn plating step in Example 1 was omitted. The results are shown in Table 1.

[0035]

[Table 1]

(Example 2) In Example 1, Cu-Z
Before n-plating, a copper plating solution made of a sulfuric acid-acidified copper sulfate solution was used for electrolytic plating for 2.2 seconds at a current density of 1.0 A / dm ² to smooth the glossy surface. The surface roughness was a center line average roughness of 0.15 μm or less. The result is even better.

[0037]

As described above, according to the present invention, it is possible to suppress the occurrence of breakage of the high temperature stretched copper foil after the copper clad laminate is manufactured.

Claims (3)

[Claims] 1. A printed circuit, comprising a high-temperature and high-strength copper foil having a glossy surface having a Vickers hardness of 65 or more after the copper-clad laminate is produced on the glossy surface side. High-temperature stretched copper foil. 2. A high-temperature and high-strength copper foil, wherein the high-temperature and high-strength copper foil expresses a roughness on a glossy side by a center line average roughness Ra.
a: A high-temperature elongation for a printed circuit characterized by having a glossy surface that is made smooth by reducing the thickness to 0.15 μm or less and at the same time has a Vickers hardness of 65 or more on the glossy side after the copper-clad laminate is manufactured. Copper foil. 3. A high-temperature stretched copper foil is provided with a layer on the glossy side which is not easily recrystallized by heat during the production of a copper-clad laminate, or an alloy plating is applied to the glossy side of the high-temperature stretched copper foil, or The Vickers hardness on the glossy side of the high-temperature stretched copper foil is 65 after the copper-clad laminate is produced by plating the glossy side of the high-temperature stretched copper foil so that it is diffused by heat during the production of the copper-clad laminate to form an alloy with copper.
A method for producing a high-temperature stretched copper foil for a printed circuit, which has a glossy surface as described above.