KR20180036693A - Roughened copper foil, copper clad laminate and printed wiring board - Google Patents

Abstract

Even in the case of fine unevenness of low light intensity suitable for formation of a fine pitch circuit and high frequency use, it is excellent not only in adhesiveness to resin but also in frictional resistance. Therefore, even after rubbing against a certain object in the production of a copper clad laminate or production of a printed wiring board, A roughened copper foil which can stably exhibit excellent adhesion with copper foil is provided. The roughened copper foil of the present invention has a roughened surface having fine irregularities composed of acicular crystals and / or tabular crystals on at least one side. The roughened surface has a maximum height Sz measured in accordance with ISO 25178 of 1.5 m or less and an arithmetic mean Spc of an acid peak measured in accordance with ISO 25178 of 1300 mm ^-1 or less.

Description

Roughened copper foil, copper clad laminate and printed wiring board

The present invention relates to a roughened copper foil, a copper clad laminate, and a printed wiring board.

As a printed wiring board copper foil suitable for formation of a fine pitch circuit, a roughened copper foil having a fine unevenness formed as a roughened surface through an oxidation treatment and a reduction treatment (hereinafter also referred to as a redox treatment) .

For example, Patent Document 1 (International Patent Publication No. 2014/126193) discloses a surface treatment copper having a surface-roughed surface layer formed of acicular or plate-like fine irregularities made of a copper composite compound having a maximum length of 500 nm or less . Patent Document 2 (International Publication No. 2015/040998) discloses a surface roughening treatment layer having fine unevenness formed of a needle-like or plate-like convex portion of a size of a maximum length of 500 nm or less made of a copper composite compound, There is disclosed a copper foil having at least one surface of a treatment layer with a silane coupling agent treatment layer on its surface. According to the roughened copper foil of these documents, good adhesion between the copper foil and the insulating resin base material can be obtained due to the anchor effect of the fine unevenness of the roughed surface treatment layer, and the fine pitch circuit with a good etching factor It is said that it is possible to form. All of the roughened surface treatment layers having fine unevenness disclosed in Patent Documents 1 and 2 are formed through a redox treatment after pretreatment such as alkali degreasing. The fine unevenness thus formed has a peculiar shape composed of an acicular crystal and / or a plate-like crystal of a copper complex compound. The roughened surface provided with such fine concavities and convexities is a surface Is roughly finer than the cotton-treated surface or the roughened surface provided with the concavities and convexities by etching.

On the other hand, with the recent enhancement of the functions of portable electronic devices and the like, signal frequency is being increased in order to perform high-speed processing of a large amount of information, and a printed wiring board suitable for high frequency applications is required. In such a high-frequency printed wiring board, it is desired to reduce the transmission loss in order to enable high-frequency signals to be transmitted without degrading the quality. The printed wiring board has a copper foil and an insulating resin base material processed into a wiring pattern. The transmission loss is mainly composed of a conductor loss caused by the copper foil and a dielectric loss caused by the insulating resin base. Further, the conductor loss can be further increased by the skin effect of the copper foil, which becomes more remarkable as the frequency becomes higher. For this reason, in order to reduce the transmission loss in high-frequency applications, a copper foil capable of reducing the conductor loss is required and a low-luminance copper foil is required. In this respect, in Patent Document 2, it is said that the copper foil having the roughed surface treatment layer described above is suitable as a high-frequency circuit forming material.

International Publication No. 2014/126193 International Publication No. 2015/040998

However, the fine irregularities formed by the oxidation-reduction treatment are not satisfactory because of friction between the copper foils (for example, when copper foil is pulled out from the roll state) or friction with other members (for example, So that the shape is easily deteriorated. This is because the fine irregularities as described above are composed of needle-like crystals and / or plate-like crystals of a copper complex compound, so that the needle-like crystals and / or the plate-like crystals may be broken or sometimes collapsed. The fine irregularities thus rubbed to deteriorate the shape not only impairs the appearance of the roughened copper foil but also reduces the anchor effect on the insulating resin base due to the fine irregularities. For this reason, there is a concern that the yield may be lowered due to poor appearance or degradation of performance (in particular, adhesion to resin).

The inventors of the present invention found that the arithmetical mean value Spc of the peak of acid measured in accordance with ISO 25178 and having a maximum height Sz measured in accordance with ISO 25178 of not more than 1.5 탆 is controlled by controlling the shape of the fine irregularities formed through the oxidation- ¹ or less, the fine irregularities having low light intensity suitable for formation of fine pitch circuits and high-frequency applications are excellent in not only adhesion to resin but also excellent friction resistance. Therefore, in the production of a copper clad laminate or production of a printed wiring board It was found that even after rubbing against an object, excellent adhesion with the resin can be stably exhibited.

Accordingly, an object of the present invention is to provide a resin composition which is excellent in not only adhesion to a resin but also resistance to abrasion, in spite of fine irregularities of low light intensity suitable for fine pitch circuit formation and high frequency use, Which is capable of stably exhibiting excellent adhesion with a resin even after rubbing against an object.

According to one aspect of the present invention, there is provided a roughened copper foil having at least one roughened surface having fine irregularities composed of needle-like crystals and / or plate-like crystals on at least one side thereof, And the arithmetic average spc of the peak of acidity measured in accordance with ISO 25178 is 1300 mm < ^-1 > or less.

According to another aspect of the present invention, there is provided a copper clad laminate having the roughened copper foil of the above aspect.

According to another aspect of the present invention, there is provided a printed wiring board having the roughened copper foil of the above aspect.

Justice

Definitions of terms and parameters used to specify the present invention are as follows.

In the present specification, the "maximum height Sz" is a parameter indicating the distance from the highest point to the lowest point of the surface, which is measured in accordance with ISO 25178. The maximum height Sz can be calculated by measuring a surface profile of a predetermined measurement area (for example, a two-dimensional area of 22500 mu m ² ) on the roughened surface with a commercially available laser microscope.

In the present specification, the "arithmetic mean curve Spc of the peak of acid" is a parameter indicating the arithmetic mean of the main curvature of the peak of acid in the positive region, which is measured in accordance with ISO 25178. [ A small value indicates that the point of contact with another object is rounded. On the other hand, a large value indicates that the point of contact with another object is sharp. Simply stated, the arithmetic mean curve Spc of the peak of the acid can be regarded as a parameter indicating the roundness of the lump, which can be measured with a laser microscope. The arithmetic mean curve Spc of the peak of the acid can be calculated by measuring a surface profile of a predetermined measuring area (for example, a two-dimensional area of 100 mu m ² ) on the roughened surface with a commercially available laser microscope.

In this specification, the term " electrode surface " of the electrolytic copper foil refers to the side of the electrolytic copper foil that was in contact with the cathode during the production of the electrolytic copper foil.

In the present specification, the term " precipitated surface " of the electrolytic copper foil refers to a surface on the side where electrolytic copper is precipitated at the time of producing the electrolytic copper foil, i.e., a surface on the side not in contact with the cathode.

Roughening treatment of copper foil

The copper foil of the present invention is a roughened copper foil. The roughened copper foil has a roughened surface on at least one side. The roughened surface includes fine irregularities composed of acicular crystals and / or plate-like crystals. These fine irregularities can be formed through oxidation-reduction treatment. Typically, acicular crystals and / (E.g., lawn-like shape) in a substantially vertical and / or oblique direction with respect to the copper foil. The surface to be roughened has a maximum height Sz measured in accordance with ISO 25178 of 1.5 m or less and an arithmetic mean Spc of an acid peak measured according to ISO 25178 is 1300 mm ^-1 or less. By controlling the shape of the fine concavities and convexities formed through oxidation-reduction processing as described above and setting the maximum height Sz to 1.5 m or less and the arithmetic mean curve Spc of the acid peak to be 1300 mm ^-1 or less, It is possible to stably provide excellent adhesion with the resin even after being rubbed on an object in the processing of a copper clad laminate or in the production of a printed wiring board It becomes possible to exercise it. In particular, as defined above, the arithmetic mean curve Spc of the peak of acid is a parameter indicating the degree of roundness of the horn, and the smaller the value, the more rounded the point of contact with another object. Therefore, it is considered that the above excellent frictional resistance is caused by the fact that the needle-like crystal and / or the plate-like crystal is not easily broken or collapsed by making the Spc to be 1300 mm ^-1 or less. That is, as described above, the fine irregularities formed by the conventional oxidation-reduction treatment are susceptible to deterioration in shape due to friction between copper foils and friction with other members, resulting in deterioration of appearance and deterioration of performance (in particular, There is a concern that the yield may be lowered due to the reduction in the surface roughness of the copper foil. However, such a technical problem can be solved by the roughened copper foil of the present invention.

The maximum height Sz on the roughened surface is 1.5 탆 or less, preferably 1.2 탆 or less, and more preferably 1.0 탆 or less. If Sz is within this range, it is more suitable for fine pitch circuit formation and high frequency use. Particularly, such a low luminance can reduce the skin effect of the copper foil, which is a problem in high frequency signal transmission, and reduce the conductor loss caused by the copper foil, thereby significantly reducing the transmission loss of the high frequency signal. The lower limit value of Sz is not particularly limited, but from the viewpoint of improving the adhesion with the resin, Sz is preferably at least 0.1 mu m, more preferably at least 0.2 mu m, even more preferably at least 0.3 mu m.

The arithmetic mean of the Song Spc acid vertex of the surface roughening treatment is 1300㎜ ^-1 or less, preferably 1200㎜ ^-1 or less, more preferably 1000㎜ ^-1 or less. In the case of Spc in these ranges, it is possible to obtain a rounded lump shape which is less likely to be rubbed, so that the friction resistance can be improved. The lower limit of Spc is not particularly limited, a 100㎜ ^-1 or more, more preferably from 200㎜ ^-1, more preferably at least 300㎜ ^-1.

As described above, the fine irregularities on the roughed surface are composed of acicular crystals and / or plate crystals. The height of the needle-like crystal and / or the plate-like crystal (that is, the height measured in the vertical direction from the root of the needle-like crystal and / or the plate-like crystal) is preferably 50 to 400 nm, more preferably 100 to 400 nm, And preferably 150 to 350 nm.

The thickness of the roughened copper foil of the present invention is not particularly limited, but is preferably 0.1 to 35 mu m, more preferably 0.5 to 18 mu m. The surface roughening treatment copper foil of the present invention is not limited to the roughening treatment of the surface of a conventional copper foil but may be a roughening treatment of the copper foil surface of the copper foil with a carrier.

Manufacturing method

The roughened copper foil according to the present invention may be produced by any method, but it is preferably produced by redox treatment. Hereinafter, an example of a preferred method for producing a roughened copper foil according to the present invention will be described. This preferred manufacturing method includes a step of preparing a copper foil having a surface having a maximum height Sz of 1.5 m or less and a roughening step (redox treatment) in which the surface is subjected to preliminary treatment, oxidation treatment and reduction treatment in sequence .

(1) Preparation of Copper foil

As the copper foil used for the production of the roughened copper foil, it is possible to use both electrolytic copper foil and rolled copper foil, and more preferably an electrolytic copper foil. Further, the copper foil may be a copper foil without a surface roughening, or it may be a pre-roughened surface. The thickness of the copper foil is not particularly limited, but is preferably 0.1 to 35 mu m, more preferably 0.5 to 18 mu m. When the copper foil is prepared in the form of a copper foil with a carrier, the copper foil is formed by a wet film formation method such as an electroless copper plating method and an electrolytic copper plating method, a dry film formation method such as sputtering and chemical vapor deposition, or a combination thereof It is acceptable.

The surface of the copper foil subjected to the roughening treatment preferably has a maximum height Sz measured according to ISO 25178 of 1.5 m or less, more preferably 1.2 m or less, and further preferably 1.0 m or less. Within the above range, the surface profile required for the roughened copper foil of the present invention, particularly the maximum height Sz of not more than 1.5 mu m, can be easily realized on the roughened surface. The lower limit value of Sz is not particularly limited, but Sz is preferably 0.1 占 퐉 or more, more preferably 0.2 占 퐉 or more, and still more preferably 0.3 占 퐉 or more.

(2) roughening treatment (redox treatment)

In this way, it is preferable to carry out the roughening process by the wet process which sequentially performs the pretreatment, the oxidation treatment and the reduction treatment on the surface of the copper foil having the low Sz. Particularly, a copper compound containing copper oxide (copper oxide) is formed on the surface of the copper foil by performing oxidation treatment on the surface of the copper foil by a wet process using a solution. Thereafter, the copper compound is subjected to a reduction treatment to convert a part of the copper oxide into copper oxide (copper oxide), whereby an acicular crystal composed of a copper complex compound containing copper oxide and copper oxide and / The irregularities can be formed on the surface of the copper foil. Here, the fine unevenness is formed by a copper compound containing copper oxide as a main component in the step of oxidizing the surface of the copper foil by the wet process. When the copper compound is subjected to the reduction treatment, a part of the copper oxide is converted to copper oxide while maintaining the shape of the fine irregularities formed by the copper compound, and the copper complex compound containing copper oxide and copper oxide . As described above, after the surface of the copper foil is subjected to an appropriate oxidation treatment by a wet method and then subjected to a reduction treatment, fine irregularities of nm order can be formed.

(2a) Preliminary processing

Prior to the oxidation treatment, the copper foil is preferably subjected to pretreatment such as degreasing. In this pretreatment, it is preferable that the copper foil is immersed in an aqueous solution of sodium hydroxide to be subjected to alkali degreasing treatment, followed by washing with water. A preferable aqueous sodium hydroxide solution has a NaOH concentration of 20 to 60 g / L and a liquid temperature of 30 to 60 DEG C, and a preferable immersion time is 2 seconds to 5 minutes. It is also preferable that the copper foil subjected to alkali degreasing treatment is dipped in an aqueous solution of sulfuric acid and then washed with water. The preferred sulfuric acid aqueous solution has a sulfuric acid concentration of 1 to 20 mass% and a liquid temperature of 20 to 50 占 폚, and the preferable immersing time is 2 seconds to 5 minutes.

(2b) oxidation treatment

The copper foil subjected to the preliminary treatment is subjected to an oxidation treatment using an alkali solution such as a sodium hydroxide solution. By oxidizing the surface of the copper foil with an alkali solution, fine irregularities composed of acicular crystals and / or plate crystals made of a copper complex compound containing copper oxide as a main component can be formed on the surface of the copper foil. At this time, the temperature of the alkali solution is preferably 60 to 85 캜, and the pH of the alkali solution is preferably 10 to 14. From the viewpoint of oxidation, the alkali solution preferably contains chlorate, chlorite, hypochlorite and perchlorate, and the concentration thereof is preferably 100 to 500 g / L. The oxidation treatment is preferably performed by immersing the electrolytic copper foil in an alkali solution, and the immersion time (that is, the oxidation time) is preferably 10 seconds to 20 minutes, more preferably 30 seconds to 10 minutes.

It is preferable that the alkali solution used for the oxidation treatment further includes an oxidation inhibitor. That is, when the surface of the copper foil is oxidized by the alkali solution, the convex portion may excessively grow to exceed the desired length, making it difficult to form the desired fine irregularities. Therefore, in order to form the fine irregularities, it is preferable to use an alkali solution containing an oxidation inhibitor capable of inhibiting oxidation on the copper foil surface. Examples of preferred oxidation inhibitors include amino silane coupling agents. An amino-based silane coupling agent in the alkali solution is adsorbed on the surface of the copper foil by performing an oxidation treatment on the surface of the copper foil by using an alkali solution containing an amino-based silane coupling agent to oxidize the copper foil surface Can be suppressed. As a result, it is possible to inhibit the growth of needle-like crystals and / or plate-like crystals of copper oxide, and to form a favorable roughened surface with extremely fine irregularities. Specific examples of the amino silane coupling agent include N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, 3- Aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1,3-dimethyl-butylidene) propylamine, N-phenyl- And particularly preferably N-2- (aminoethyl) -3-aminopropyltrimethoxysilane. All of these are dissolved in the alkaline solution, stably maintained in the alkaline solution, and exhibit the effect of inhibiting oxidation of the surface of the copper foil described above. The preferred concentration of the amino-based silane coupling agent (for example, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane) in the alkali solution is 0.01 to 20 g / L, 20 g / L.

(2c) Reduction treatment

The copper foil subjected to the oxidation treatment (hereinafter referred to as oxidation-treated copper foil) is subjected to a reduction treatment using a reducing treatment liquid. By converting a part of the copper oxide into copper oxide (copper oxide) by reduction treatment, fine irregularities composed of acicular crystals and / or plate crystals composed of a copper complex compound containing copper oxide and copper oxide are formed on the surface of the copper foil As shown in Fig. This reduction processing is performed, but the reduction by contacting the treatment liquid for the oxidation treatment of copper foil, wherein the reducing treatment to form a raised the amount of dissolved oxygen is, 1300㎜ ^-1 or less of the acid peak of the arithmetic mean of the Song Spc roughening treated surface of the liquid . By increasing the amount of dissolved oxygen, it is considered that the oxidation effect by the dissolved oxygen and the reducing power by the reducing agent can be balanced, thereby realizing the Spc. Examples of the method for increasing the amount of dissolved oxygen in the reducing treatment liquid include a method of immersing the oxidized copper foil while stirring the reducing treatment liquid and a method of spraying the reducing treatment liquid to the oxidized copper foil with a shower. Particularly preferably, the reduction treatment liquid is sprayed by a shower in that a preferable Spc can be realized easily. In this case, the time for spraying the reduction treatment liquid with a shower may be short, about 2 to 60 seconds, Preferably 5 to 30 seconds. The preferred reducing treatment liquid is an aqueous solution of dimethylamine borane, and the aqueous solution preferably contains dimethylamine borane at a concentration of 10 to 40 g / L. The aqueous solution of dimethylamine borane is preferably adjusted to pH 12-14 using sodium carbonate and sodium hydroxide. The temperature of the aqueous solution at this time is not particularly limited and may be room temperature. The copper foil thus subjected to the reduction treatment is preferably washed with water and dried.

(3) Rust treatment

The copper foil after the roughening treatment may be subjected to a rust-preventive treatment to form a rust-preventive layer. Examples of the rust-preventive layer include an inorganic rust-preventive layer using an inorganic component, an organic rust-preventive layer using an organic component, and combinations thereof. Preferred inorganic rust-preventive layers include one or more elements such as zinc, tin, nickel, cobalt, molybdenum, tungsten, titanium, and chromium. The preferred organic rust preventive layer comprises a triazole compound, more preferably a benzotriazole, a carboxybenzotriazole, a methylbenzotriazole, an aminotriazole, a nitrobenzotriazole, a hydroxybenzotriazole, a chlorobenzotriazole Sol, ethylbenzotriazole, naphthotriazole, or any combination thereof.

(4) Treatment with silane coupling agent

The copper foil after the roughening treatment may be subjected to a silane coupling agent treatment to form a silane coupling agent layer. As a result, it is possible to improve the moisture resistance, chemical resistance, adhesion with the adhesive, and the like. The silane coupling agent layer can be formed by appropriately diluting a silane coupling agent, applying it, and drying it. Examples of the silane coupling agent include epoxy functional silane coupling agents such as 4-glycidylbutyltrimethoxysilane and 3-glycidoxypropyltrimethoxysilane, or 3-aminopropyltriethoxysilane, N-2 ( Aminopropyltrimethoxysilane, N-3- (4- (3-aminopropoxy) butoxy) propyl-3-aminopropyltrimethoxysilane, N-phenyl- Amino functional silane coupling agents such as trimethyl silane, amino silane coupling agents such as trimethyl silane, amino silane coupling agents such as trimethyl silane, amino silane coupling agents such as trimethyl silane, A coupling agent or an acrylic functional silane coupling agent such as 3-methacryloxypropyltrimethoxysilane, or an imidazole functional silane coupling agent such as imidazole silane, or a triazine functional silane coupling agent such as triazinilane .

Further, the above-mentioned rust-proofing treatment and the silane coupling agent treatment as described above may be performed.

Tie Laminates

The roughened copper foil of the present invention is preferably used for producing a copper-clad laminate for a printed wiring board. That is, according to a preferred embodiment of the present invention, there is provided a copper clad laminate provided with the roughened copper foil or a copper clad laminate obtained using the roughened copper foil. The copper clad laminate comprises the roughened copper foil of the present invention and a resin layer formed in close contact with the roughened surface of the roughened copper foil. The roughened copper foil may be provided on one side of the resin layer or on both sides. The resin layer comprises a resin, preferably an insulating resin. The resin layer is preferably a prepreg and / or a resin sheet. The term "prepreg" is a collective term for a composite material obtained by impregnating a base material such as a synthetic resin plate, a glass plate, a glass woven fabric, a glass nonwoven fabric, or paper with a synthetic resin. Preferable examples of the insulating resin include an epoxy resin, a cyanate resin, a bismaleimide triazine resin (BT resin), a polyphenylene ether resin, a phenol resin, and the like. Examples of the insulating resin constituting the resin sheet include insulating resins such as epoxy resin, polyimide resin and polyester resin. Further, the resin layer may contain filler particles composed of various inorganic particles such as silica and alumina from the viewpoint of improving the insulating property and the like. The thickness of the resin layer is not particularly limited, but is preferably 1 to 1000 占 퐉, more preferably 2 to 400 占 퐉, and still more preferably 3 to 200 占 퐉. The resin layer may be composed of a plurality of layers. A resin layer such as a prepreg and / or a resin sheet may be provided in the roughened copper foil through a primer resin layer previously coated on the copper foil surface.

print Wiring board

The roughened copper foil of the present invention is preferably used for producing a printed wiring board. That is, according to a preferred embodiment of the present invention, there is provided a printed wiring board having the roughened copper foil or a printed wiring board obtained using the roughened copper foil. The printed wiring board according to this embodiment comprises a layer structure in which a resin layer and a copper layer are stacked in this order. The resin layer is as described above for the copper clad laminate. In any case, a known layer structure can be employed for the printed wiring board. As specific examples of the printed wiring board, a single-sided or double-sided printed wiring board formed by bonding a roughened surface-treated copper foil of the present invention to one side or both sides of a prepreg and then curing it, and a multilayer printed wiring board . As another specific example, a flexible printed wiring board, a COF, a TAB tape, or the like that forms a circuit by forming the roughened copper foil of the present invention on a resin film may be used. As another specific example, a copper foil (RCC) with a resin coated with the resin layer described above is formed on the roughened copper foil of the present invention, the resin layer is laminated on the above-mentioned printed board as an insulating adhesive layer, The processed copper foil may be a build-up wiring board in which a circuit is formed by a modulated semi-additive (MSAP) method, a subtractive method or the like as all or a part of the wiring layer, or a semi-additive ) Method, and a direct build-up wafer in which a lamination of a resin-coated copper foil and a circuit formation are alternately repeated on a semiconductor integrated circuit.

Example

The present invention will be described more specifically with reference to the following examples.

Examples 1-10

The roughened copper foil of the present invention was produced as follows.

(1) Production of electrolytic copper foil

A solution temperature of 45 캜 and a current density of 55 A / dm < 2 > (current density of 55 A / dm 2) was used as a copper electrolyte, a sulfuric acid- ² to obtain an electrolytic copper foil having a thickness of 12 탆. The maximum height Sz of the precipitated surface and the electrode surface of the electrolytic copper foil was measured by the method described later. The Sz of the precipitated surface was 0.8 mu m and the Sz of the electrode surface was 1.2 mu m.

<Composition of Sulfuric Acid Sulfuric Acid Solution>

- Copper concentration: 80g / L

- sulfuric acid concentration: 260 g / L

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

- diallyldimethylammonium chloride Polymer concentration: 50 mg / L

- Chlorine concentration: 40 mg / L

(2) roughening treatment (redox treatment)

(Oxidation-reduction treatment) was performed on the electrode surface side (Examples 1 to 5) or the precipitation surface side (Examples 6 to 10) of the obtained electrolytic copper foil by the following three-step process. That is, the preliminary treatment, the oxidation treatment and the reduction treatment shown below were performed in this order.

<Preliminary treatment>

The electrolytic copper foil obtained in the above (1) was immersed in an aqueous solution of sodium hydroxide having an NaOH concentration of 50 g / L for 1 minute at a liquid temperature of 40 占 폚, subjected to alkaline degreasing treatment, and then washed with water. The electrolytic copper foil subjected to the alkali degreasing treatment was immersed in a sulfuric acid aqueous solution having a sulfuric acid concentration of 5% by mass for 1 minute and then washed with water.

<Oxidation Treatment>

The electrolytic copper foil subjected to the preliminary treatment was subjected to an oxidation treatment. This oxidation treatment was carried out in the same manner as in Example 1 except that the electrolytic copper foil was subjected to hydrolysis at a liquid temperature of 70 DEG C, a pH of 12, a chloric acid concentration of 150 g / L and a concentration of N-2- (aminoethyl) -3-aminopropyltrimethoxysilane of 10 g / Sodium solution by the time immersion described in Table 1. In this manner, fine irregularities composed of needle-like crystals and / or plate-like crystals made of a copper complex compound containing copper oxide as a main component were formed on both surfaces of the electrolytic copper foil.

<Reduction Treatment>

A sample subjected to the oxidation treatment was subjected to reduction treatment. In this reduction treatment, an aqueous solution having a dimethylamine borane concentration of 20 g / L adjusted to pH = 12 by using sodium carbonate and sodium hydroxide was added to the electrode surface side or the precipitation surface side of the electrolytic copper foil having fine irregularities formed by the above- Followed by spraying with a second shower. At this time, the temperature of the aqueous solution was set to room temperature. The sample thus subjected to the reduction treatment was washed with water and dried. By these steps, a part of the copper oxide on one side of the electrolytic copper foil was reduced to be made into a copper oxide and a roughened surface having fine irregularities made of a copper complex compound containing copper oxide and copper oxide. Thus, roughened copper foil having a roughened surface having fine irregularities composed of acicular crystals and / or plate-like crystals on at least one side was obtained.

Example 11 (comparative)

Roughened copper foil was produced in the same manner as in Example 2 except that the adhesion of the aqueous solution in the reduction treatment was carried out by immersing the sample subjected to the oxidation treatment in an aqueous solution instead of using a shower.

Examples 12 and 13 (comparative)

(Example 12) or the electrode surface side (Example 13) of the electrolytic copper foil obtained in the same manner as in (1) of Example 1 was subjected to pretreatment in the same manner as in Example 1 (2) Oxidation treatment and reduction treatment (redox treatment) were carried out to prepare a roughened copper foil.

<Oxidation Treatment>

The electrolytic copper foil was subjected to oxidation treatment. In this oxidation treatment, the electrolytic copper foil was treated with 10 vol% of "PRO BOND 80A OXIDE SOLUTION" which is an oxidation treatment solution manufactured by Rohm and Haas Electronic Materials Co., Ltd. and 20 vol% of "PRO BOND 80B OXIDE SOLUTION" In an aqueous solution for 5 minutes.

<Reduction Treatment>

The electrolytic copper foil subjected to the oxidation treatment was subjected to reduction treatment. In this reduction treatment, the electrolytic copper foil subjected to the oxidation treatment was added with 6.7 vol% of "CIRCUPOSIT PB OXIDE CONVERTER 60C" which is a reduction treatment solution manufactured by Rohm & Haas Electronic Materials Co., Ltd., a liquid temperature 35 containing 1.5 vol% of "CUPOSITZ" Lt; 0 &gt; C for 10 seconds with a shower. The sample thus subjected to the reduction treatment was washed with water and dried.

Examples 14 and 15 (comparative)

The reducing treatment was carried out in the same manner as in Example 12 (Example 14) or Example 13 (Example 15) except that the reduction treatment was carried out by immersing the sample subjected to the oxidation treatment in the aqueous solution for 5 minutes instead of using the shower A cotton-treated copper foil was produced.

evaluation

The roughened copper foil produced in Examples 1 to 15 was subjected to various evaluations described below.

<Maximum height Sz>

The maximum height Sz on the roughened surface of the roughened copper foil was measured according to ISO25178 by the surface property analysis using a laser microscope (VK-X100, manufactured by Kikusui Chemical Co., Ltd.). Specifically, the surface profile of the two-dimensional region having an area of 22500 μm ² on the roughened surface of the roughened copper foil was measured by the laser method. And the average value at the three points in the same sample was adopted as the value of the maximum height Sz. The maximum height Sz of the deposition surface or the electrode surface of the electrolytic copper foil before the roughening treatment in each of the examples described above was also measured in the same manner as described above.

<Arithmetic average song of mountain peak Spc>

The arithmetic mean curve Spc of the peak of acid on the roughened surface of the roughened copper foil was measured according to ISO 25178 by the surface property analysis using a laser microscope (VK-X100, manufactured by Kubu Co., Ltd.) . Specifically, the surface profile of a two-dimensional area having an area of 100 mu m &lt; ² &gt; on the roughened surface of the roughened copper foil was measured by a laser method. The average value obtained when 10 samples were measured for the same sample was adopted as the arithmetic mean curve Spc of the acid peak.

<Friction resistance - Lightness difference before and after the friction test? L>

(ΔL) of the lightness L * (in the L * a * b * colorimetric system) of the roughened surface of the roughened copper foil before and after the friction test to evaluate the abrasion resistance of the roughened copper foil, Were measured. The lightness L * was measured in accordance with JIS Z8722: 2000 using a spectral colorimeter (SE2000 manufactured by Nippon Denshoku Kogyo Co., Ltd.). At this time, a white plate attached to the measuring apparatus was used for calibrating the brightness. This measurement was performed three times for the same region, and the average value of the three measured values was adopted as the value of the brightness L * of the roughened copper foil. Next, as a friction test, a plurality of the roughed surface treated copper foils were laminated, and while applying a load of 5 kgf / cm &lt; 2 &gt; from the resulting laminate, one roughened copper foil . The lightness L * of the roughened surface of the drawn copper-treated copper foil was measured in the same manner as described above. The difference (? L) of the brightness L * before and after the friction test thus obtained was used as an evaluation index of the frictional resistance. Concretely, it was judged that the lightness difference? L before and after the friction test was 10 or less, and &quot; good &quot;

&Lt; Adhesion with resin - Peel strength after friction test >

As the insulating resin base material, two prepregs (MEGTRON4, thickness: 100 mu m, manufactured by Panasonic Corporation) were prepared and laminated. The roughened prepreg was laminated such that the roughened surface of the roughened copper foil subjected to the friction test (drawn out from the laminate while applying a load) was in contact with the prepreg, and using a vacuum press, Pressed at a press pressure of 2.9 MPa, a temperature of 200 캜, and a press time of 90 minutes to prepare a copper clad laminate. Next, a test board having a linear circuit for measuring a peel strength of 3.0 mm in width was formed on the copper-clad laminate by an etching method. The linear circuit thus formed was peeled from the insulating resin base material in accordance with JIS C6481-1996, and the peel strength (kgf / cm) was measured.

result

The evaluation results obtained in Examples 1 to 15 were as shown in Table 1. As shown in Table 1, the roughened copper foils obtained in Examples 1 to 10 satisfying the conditions of the present invention were excellent in resistance to abrasion and adhesion to resin after the friction test.

Claims (7)

Wherein the surface to be roughened is a roughened copper foil having at least one roughened surface having fine irregularities composed of acicular crystals and / or plate-like crystals, wherein the roughened surface has a maximum height Sz measured in accordance with ISO 25178 of 1.5 Mu m or less and an arithmetic mean Spc of an acid peak measured in accordance with ISO 25178 is 1300 mm &lt; ^-1 &gt; or less. The method according to claim 1,
Wherein the acicular phase and / or the plate phase has a height of 50 to 400 nm. 3. The method according to claim 1 or 2,
Wherein the maximum height Sz is 0.2 to 1.0 占 퐉. 4. The method according to any one of claims 1 to 3,
Wherein the arithmetic mean curve Spc of the acid peak is 200 to 1000 mm &lt; ^{-1 &} gt ;. 5. The method according to any one of claims 1 to 4,
Wherein the fine unevenness is formed by oxidation-reduction treatment. A copper clad laminate comprising the roughened copper foil according to any one of claims 1 to 5. A printed wiring board comprising the roughened copper foil according to any one of claims 1 to 5.