JP2014058704A - Rolled copper foil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rolled copper foil stably providing flexibility.SOLUTION: When a crystal orientation in an RD direction is displayed with a stereo triangle after heating at 200°C for 0.5 hours, 36 boxes are displayed by dividing the stereo triangle display by 5 degrees with ω and ψ respectively, a [001] direction is set as a box number 1 and thereafter box numbers are increased with increasing ω and ψ, then the box number of a [111] direction is set as 36, where ψ is an angle between the [100] direction and the RD direction of the sample, ω is a value obtained by tanω=tanλ tanψ, λ is an angle between the [001] direction and an ND direction of the sample, a rolled copper foil satisfies an average strength Iof the box number 1 of 20 or more, any average strength I, Iand Iof crystal orientations corresponding the box numbers 7, 11 and 16 of 1.5 or less, 1.0 or less, and 0.5 or less respectively.

Description

  The present invention relates to a rolled copper foil used for, for example, a flexible printed circuit (FPC) and suitable for a copper-clad laminate.

  A flexible wiring board (FPC) is formed by laminating a resin layer and a copper foil, and is preferably used for repeated bent portions. As copper foil used for such FPC, rolled copper foil excellent in flexibility is widely used. As a method for improving the flexibility of the rolled copper foil, a technique for developing a cubic texture after recrystallization annealing has been reported (Patent Document 1). Further, as a method of developing a cube texture after recrystallization annealing, the final cold rolling degree and rolling conditions are specified (Patent Document 2), or the cube orientation is left after the final cold rolling (Patent Document 3). ).

Japanese Patent No. 3009383 JP 2009-185376 A JP 2010-150597 A

However, the conventional method for developing a cube texture is to adjust the degree of final cold rolling, so that the thickness of the copper foil material during annealing before final cold rolling where the cube texture grows depends on the thickness of the final product. Therefore, there is a problem that productivity is reduced because it is necessary to perform cold rolling under special conditions.
Conventionally, the degree of development of the cubic texture has been evaluated using the X-ray diffraction average intensity of the {200} plane of the copper foil surface. However, since the stress when the copper foil is actually deformed by bending is in the in-plane direction of the copper foil, particularly the longitudinal direction of the material, it is the in-plane that directly affects the flexibility of the copper foil. The crystal orientation in the rolling direction (RD direction). Therefore, in order to improve the flexibility of the copper foil, it is important to orient the crystal in the RD direction.

  That is, this invention is made | formed in order to solve said subject, and it aims at provision of the rolled copper foil which can obtain the outstanding flexibility stably.

  As a result of various studies, the present inventors have found that excellent bending properties can be obtained when there are many [001] orientations of the copper foil in the RD direction.

That is, the rolled copper foil of the present invention displays the crystal orientation in the RD direction in stereo triangles after heating at 200 ° C. for 0.5 hours, and the stereo triangle display is divided into 36 boxes by dividing each of the stereo triangles by ω and ψ. , The [001] azimuth is box number 1, the box number is increased as ω is larger and ψ is larger, and the [111] direction is box number 36 (where ψ is [ 100] direction and the RD direction of the sample, ω is a value obtained by tan ω = tan λ · tan ψ, and λ is the [001] direction and the ND direction of the sample (direction perpendicular to the rolling surface) preparative angle) is, and the average intensity _{I 1} of the box number 1 is 20 or more, and an average intensity _I 7 crystal orientation corresponding to the box number _{7,11,16, I 11,} I _16, respectively 1. Hereinafter, 1.0, satisfies either of 0.5 or less.

In the rolled copper foil of the present invention, the crystal orientation in the RD direction is displayed in stereo triangle, and this stereo triangle display is divided by 5 degrees each at ω and ψ to display 36 boxes, and the [001] orientation is displayed. When the box number is 1, and ω is larger and ψ is larger and the box number is larger and the [111] orientation is the box number 36 (where ψ is the [100] orientation and the RD of the sample) Ω is a value obtained by tan ω = tan λ · tan ψ, λ is an angle formed by the [001] orientation and the ND direction of the sample) and the average intensity I ₁ of box number ₁ is 20 or more. In addition, the average intensities I ₇ , I ₁₁ , and I _{16 of} crystal orientations corresponding to the box numbers ₇ , ₁₁ , and ₁₆ satisfy 1.5 or less, 1.0 or less, and 0.5 or less, respectively.

For the average intensities I ₁ , I ₇ , I ₁₁ , I ₁₆ , (I ₇ / I ₁ ) × 100 (%) is 8 or less, and (I ₁₁ / I ₁ ) × 100 (%), (I ₁₆ / I ₁ ) × 100 (%) preferably satisfies 5 or less and 3 or less, respectively.
It is preferable that I ₇ , I ₁₁ , and I ₁₆ satisfy all of 1.5 or less, 1.0 or less, and 0.5 or less, respectively.
In the state before the final cold rolling and after the recrystallization annealing, the stereo triangle is displayed, and the box is displayed, and the average intensities of the crystal orientations corresponding to the box numbers 1, 7, 11, and 16 are set as I _1b , I _7b , I _11b , I _16b and when the final cold rolling degree is η (where η = Ln {(thickness before final cold rolling) / (thickness after final cold rolling)}), (I _7b / I _1b / η) × 100 (%) is preferably 1 or more and 4 or less.
It is preferable that (I _11b / I _1b / η) × 100 (%) and (I _16b / I _1b / η) × 100 (%) satisfy either 6 or less and 4 or less, respectively.
It is preferable that η ≧ 2.3.
The copper clad laminate of the present invention comprises the copper foil and a resin.

  According to the present invention, a rolled copper foil having excellent flexibility can be obtained stably.

It is a figure which shows the example which stereo-projected the stereogram of the reverse pole figure of the three-dimensional crystal orientation of a texture, and displayed it. It is a figure which shows the example which divided | segmented and displayed the stereo triangle display in 36 boxes. It is a figure which shows the method of measuring a bending fatigue life with a bending test apparatus.

  Hereinafter, the rolled copper foil which concerns on embodiment of this invention is demonstrated. The rolled copper foil according to the embodiment of the present invention is suitable for a battery current collector, a tab, and the like because it has excellent flexibility and exhibits high resistance to repeated deformation.

<Ingredient composition>
As the component composition of the copper foil, tough pitch copper (TPC) standardized to JIS-H3100 (C1100) or oxygen-free copper (OFC) of JIS-H3100 (C1020) can be suitably used. Further, Sn as an additive element may be contained in an amount of 10 to 500 ppm by mass, and / or Ag may be contained in an amount of 10 to 500 ppm by mass, and the balance may be the tough pitch copper or oxygen-free copper.
Further, as an additive element, at least one element selected from the group consisting of Sn, Ag, In, Ti, Zn, Zr, Fe, P, Ni, Si, Te, Cr, Nb, B, and V is 10 to 500 mass in total. It may contain ppm, and the balance may be the tough pitch copper or oxygen-free copper.
In addition, since the rolled copper foil used for FPC is requested | required of flexibility, the thickness of a rolled copper foil has preferable 20 micrometers or less. The lower limit of the thickness of the rolled copper foil is not particularly limited, but is preferably 4 μm or more, more preferably 5 μm or more in consideration of manufacturability.

<Crystal orientation of rolled copper foil>
The rolled copper foil according to the embodiment of the present invention displays the crystal orientation in the RD direction as a stereo triangle after heating at 200 ° C. for 0.5 hours, and this stereo triangle display is divided into 36 parts each by 5 degrees by ω and ψ. When the [001] direction is set to box number 1, the ω is increased and ψ is increased so that the box number increases, and the [111] direction is set to box number 36.
And the average intensity _{I 1} of the box number 1 is 20 or more, and an average intensity _I 7 of a corresponding crystal orientations respectively box number _{7,11,16, I 11,} I ₁₆ of 1.5 or less, respectively, 1.0 Or 0.5 or less.
Here, the RD direction is the rolling direction of the copper foil. Ψ is an angle formed by the [100] orientation and the RD direction of the sample, ω is a value obtained by tan ω = tan λ · tan ψ, and λ is an angle formed by the [001] orientation and the ND direction of the sample. By specifying the two angles ω and ψ, the crystal orientation relative to the material can be specified.
In addition, when joining copper foil with a resin film and making it CCL (copper clad laminated board), heat is added to copper foil. Then, the crystal orientation of copper foil is measured in the state which heated copper foil on the heat processing conditions (200 degreeC for 30 minutes) imitating the temperature history provided to copper foil in a CCL manufacturing process.

Here, stereo triangle display and box display will be described with reference to FIGS.
As shown in FIG. 1, it is common practice to measure the three-dimensional crystal orientation of a texture by an inverse pole figure method, and further project the inverse pole figure in stereo to display a stereo triangle ((1) PD). Ruer and R. Baro: J. Appl. Cryst., 10 (1977), 458, (2) Shinichi Nagashima, “Three-dimensional analysis of textures by the vector method”, The Japan Institute of Metals, 21 (1982), p842) . In addition, FIG. 1, FIG. 2 quoted from the said literature (2).
Further, as shown in FIG. 2, when the stereo triangle display is divided by 5 degrees each at ω and ψ, 36 boxes are displayed in the triangle. Then, the stereo triangle [001] orientation is set to box number 1, and hereinafter, the box number increases as ω increases (to the right in FIG. 2) and ψ increases (to the top in FIG. 2). Give a serial number. For example, box number 2 is adjacent to box number 1 and ω is 5 degrees larger and ψ is 0 degrees, and box number 3 is the same as box number 2 and ω and ψ is 5 degrees larger. In this way, the [111] orientation of the stereo triangle is set to box number 36. In box number 36, ω = ψ = 45 degrees.

As a result of various studies, the present inventors have found that excellent bending properties can be obtained when there are many [001] orientations of the copper foil in the RD direction. Since box number 1 (the left end of the triangle) in the stereo triangle display represents the [001] orientation of the crystal orientation, if the X-ray intensity (average intensity) in the RD direction in box number 1 is high, the RD direction of the material and the crystal The [001] direction of is approaching. Therefore, the average intensity I ₁ of box number 1 is defined as 20 or more. On the other hand, the upper limit of I ₁ need not be specified, but is 60 or less, for example, 55 or less, for example 50 or less, for example 45 or less.

In addition, the average intensity (X-ray intensity) of the crystal orientation corresponding to each box number is determined by the pole figure measurement when the sample to be measured is X-ray diffracted using the Schulz reflection method, and the X of the pure copper powder sample. Based on the line diffraction measurement, the diffraction intensity at each measurement point of the target sample is divided by the value of the pure copper powder and normalized (referred to as normalized intensity). If the X-ray intensity of a specific box is 1, it is the same as the X-ray diffraction intensity of a random pure copper powder sample having no texture, indicating that there is no accumulation in that direction.
In the present invention, the X-ray intensity of each box is represented by “average intensity”. The “average intensity” is the sum of the normalized intensities at each of a plurality of measurement points included in the area (φ5 ° × ω5 ° area) occupied by the corresponding box divided by the number of measurement points included in the area. Value.

Here, if the ratio of crystal grains having an orientation other than the [001] orientation corresponding to the box number 1 is large, the stress application direction and the slip direction are close to each other at the time of bending, so that slip deformation is unlikely to occur and flexibility is lowered. . In particular, the orientations corresponding to the box numbers 7, 11, and 16 are unlikely to slip.
Therefore, it is necessary that the average intensities I ₇ , I ₁₁ , I _{16 of} the crystal orientations corresponding to the box numbers ₇ , ₁₁ , ₁₆ respectively satisfy one of 1.5 or less, 1.0 or less, or 0.5 or less. It is.

Furthermore, for I ₁ , I ₇ , I ₁₁ , and I ₁₆ , (I ₇ / I ₁ ) × 100 (%) is 8 or less, and (I ₁₁ / I ₁ ) × 100 (%), (I ₁₆ / I ₁ ) × 100 (%) preferably satisfies 5 or less and 3 or less, respectively.
As the values of (I ₇ / I ₁ ), (I ₁₁ / I ₁ ), and (I ₁₆ / I ₁ ) are smaller, the ratio of the [001] orientation that contributes to the flexibility increases and the flexibility is improved. The lower the values of (I ₇ / I ₁ ), (I ₁₁ / I ₁ ), and (I ₁₆ / I ₁ ), the higher the flexibility, but typically these values are 0.1% or more. It is.
A copper foil product that has already been subjected to the above-mentioned “heating at 200 ° C. for 0.5 hour” may be shipped. Therefore, the invention according to claim 2 is intended for a product after shipping that has already been annealed, and even if the product is not further annealed, the crystal orientation in the RD direction is displayed as a stereo triangle, This stereo triangle display is divided by 5 degrees each at ω and ψ to display 36 boxes, the [001] direction is box number 1, and hereinafter, the box number increases as ω increases and ψ increases. as the [111] when the a box number 36 orientation, and the average intensity _{I 1} of the box number 1 is 20 or more, and an average intensity _I 7 of a corresponding crystal orientations respectively box number 7,11,16, I ₁₁ and I ₁₆ satisfy any one of 1.5 or less, 1.0 or less, or 0.5 or less, respectively.

<Manufacture of rolled copper foil>
The rolled copper foil according to the embodiment of the present invention can be manufactured by hot rolling an ingot, and after repeating cold rolling and annealing, cold rolling before annealing, recrystallization annealing, and final cold rolling. it can.
In general, in the copper foil manufacturing process, the degree of workability of the final cold rolling process is high, so even if the structure before the final cold rolling is controlled, the effect tends not to remain sufficiently until after the final cold rolling. Therefore, by managing both the structure before the final cold rolling and the workability of the final cold rolling, the crystal orientation is obtained in the copper foil after heating at 200 ° C. for 0.5 hours, and sufficient flexibility is obtained. can get.
In this case, when the sample before the final cold rolling and after the recrystallization annealing is displayed in the above stereo triangle and box display, the average intensity of the crystal orientations corresponding to the box numbers 1, 7, 11 and 16 is expressed as I _1b. , I _7b , I _11b , I _16b, and recrystallization annealing conditions and final cold rolling before final cold rolling so that (I _7b / I _1b / η) × 100 (%) is 1 or more and 4 or less. It is desirable to select the degree. (I _7b / I _1b / η) × 100 (%) is more preferably 1 or more and 3 or less. However, η = Ln {(thickness before final cold rolling) / (thickness after final cold rolling)}.
When (I _7b / I _1b / η) × 100 (%) exceeds 4, the above crystal orientation cannot be obtained in the copper foil heated at 200 ° C. for 0.5 hours after the final cold rolling, and sufficient flexibility is obtained. It may not be obtained. The lower the value of (I _7b / I _1b / η) × 100 (%), the higher the flexibility, but practically it is a value of 1% or more.

Further, the final cold rolling is performed so that (I _11b / I _1b / η) × 100 (%) and (I _16b / I _1b / η) × 100 (%) satisfy 6 or less and 4 or less, respectively. It is desirable to select the previous recrystallization annealing conditions and the final cold rolling degree. It is more preferable that (I _11b / I _1b / η) × 100 (%) is 1 or more and 5 or less. (I _16b / I _1b / η) × 100 (%) is more preferably 1 or more and 3 or less.
In order to control (I _7b / I _1b / η) × 100 (%) to 1 or more and 4 or less in the sample before the final cold rolling and after the recrystallization annealing, the recrystallization annealing before the final cold rolling is performed. In this case, it is preferable that the heating rate is 5 to 50 ° C./s. If the heating rate is too high, the crystal orientation becomes random, and (I _7b / I _1b / η) × 100 (%) increases. If the rate of temperature increase is too slow, the productivity is lowered.
In the sample before the final cold rolling and after the recrystallization annealing, (I _11b / I _1b / η) × 100 (%) and (I _16b / I _1b / η) × 100 (%) were 6 respectively. Hereinafter, in order to control to satisfy any of 4 or less, it is preferable that the temperature increase rate at the time of recrystallization annealing before the final cold rolling is 5 to 45 ° C./s. If the rate of temperature rise is too high, I _11b / I _1b / η) × 100 (%) and (I _16b / I _1b / η) × 100 (%) increase. If the rate of temperature increase is too slow, the productivity is lowered.

The workability η of the final cold rolling is preferably 2.3 or more. If η is less than 2.3, it is difficult for I ₁ , I ₇ , I ₁₁ , and I ₁₆ to satisfy the above relationship.

  First, a copper ingot having the composition shown in Table 1 was manufactured and hot-rolled to a thickness of 10 mm. Thereafter, cold rolling and annealing were repeated, and then cold rolling before annealing to a predetermined thickness, followed by recrystallization annealing in an annealing furnace set at a temperature of 700 to 800 ° C. Furthermore, the final cold rolling was performed at a workability (η) shown in Table 2 to obtain a copper foil having a thickness shown in Table 1. Table 1 shows the rate of temperature increase during recrystallization annealing.

<Crystal orientation>
After the copper foil obtained by the final cold rolling was recrystallized by heating at 200 ° C. for 0.5 hour, using an X-ray diffractometer (RINT-2500: manufactured by Rigaku Corporation), (111), ( 200), (311) plane positive electrode point measurement (X-ray reflection average intensity) was performed. The obtained measurement result was converted into a reverse pole expression using Standard ODF (manufactured by Norm Engineering Co., Ltd.). The converted inverse pole data was converted into stereo triangle display in the RD direction (box notation divided into 36 within this triangle) using InverseDisp (manufactured by Helpertex) which is analysis support software.
The measurement conditions of X-ray diffraction are incident X-ray source: Co, acceleration voltage: 30 kV, tube current: 100 mA, divergence slit: 0.5 degree, scattering slit: 4 mm, light receiving slit: 4 mm, divergence longitudinal limiting slit: 1. It was 2 mm. Moreover, it normalized using the value (X-ray reflection average intensity) of the pure copper powder which performed the X-ray diffraction on the same conditions. In addition, the X-ray intensity of each box was represented by “average intensity”. The “average intensity” is the sum of the normalized intensities at each of a plurality of measurement points included in the area (φ5 ° × ω5 ° area) occupied by the corresponding box divided by the number of measurement points included in the area. Value.
Moreover, it measured similarly by the above-mentioned method also about the sample after the recrystallization annealing in the annealing furnace set to the temperature of 700-800 degreeC before the last cold rolling.

<Flexibility>
After the copper foil sample obtained by final cold rolling was recrystallized by heating at 200 ° C. for 0.5 hour, the bending fatigue life was measured by a bending test apparatus shown in FIG. This apparatus has a structure in which a vibration transmitting member 3 is coupled to an oscillation driver 4, and a copper foil 1 to be tested is fixed to the apparatus at a total of four points including a screw 2 part indicated by an arrow and a tip part of 3. Is done. When the vibration part 3 is driven up and down, the intermediate part of the copper foil 1 is bent into a hairpin shape with a predetermined radius of curvature r. In this test, the number of times until breakage when bending was repeated under the following conditions was determined.
The test conditions are as follows: Specimen width: 12.7 mm, Specimen length: 200 mm, Specimen sampling direction: Collected so that the length direction of the specimen is parallel to the rolling direction, curvature radius r : 1.5 mm, vibration stroke: 20 mm, vibration speed: 1000 times / min.
Further, the flexibility was evaluated according to the following criteria. If evaluation is (double-circle), (circle), or (triangle | delta), flexibility is favorable.
◎: The number of bendings is 200,000 times or more and the flexibility is the best. ○: The number of bendings is 100,000 or more and less than 200,000 times, and the flexibility is good. △: The number of bendings is 50,000 or more and less than 100,000. , Excellent flexibility ×: less than 50,000 times of bending, poor flexibility

The obtained results are shown in Tables 1 and 2.
Here, “TPC” in the composition column in Table 1 represents tough pitch copper (TPC) standardized to JIS-H3100 (C1100), and “OFC” represents oxygen-free copper (OFC) standardized to JIS-H3100 (C1020). Represents. Therefore, for example, “190 ppmAg-TPC” in the composition column in Table 1 means a composition in which 190 mass ppm of Ag is added to tough pitch copper (TPC) standardized to JIS-H3100 (C1100). In addition, “100 ppm Sn—OFC” in the composition column of Table 1 means a composition in which 100 mass ppm of Sn is added to oxygen-free copper (OFC) specified in JIS-H3100 (C1020).
In Tables 1 and 2, values such as (I ₇ / I ₁ ) are represented in% (that is, (I ₇ / I ₁ ) × 100).

As it is evident from Table 1, and the average intensity _{I 1} of the box number 1 is 20 or more, and one of each box number 7,11,16 average intensity _I 7 of a corresponding crystal _orientation, I _{11, I 16} In each of the examples in which the values were 1.5 or less, 1.0 or less, and 0.5 or less, the flexibility was excellent.

As is apparent from Table 1, any of the average intensities I ₇ , I ₁₁ , I ₁₆ of the crystal orientations corresponding to the box numbers ₇ , ₁₁ , ₁₆ is 1.5, 1.0, 0.5, respectively. In Examples 2, 10, 13, 14, 19, 21, and 23 that exceeded the range, the flexibility was slightly lowered as compared with the other examples, but there was no practical problem.
As is clear from Table 2, (I _7b / I _1b / η) × 100 (%) was 1 or more and 4 or less in all Examples. In each of the examples except Examples 13 and 14, (I _11b / I _1b / η) × 100 (%) and (I _16b / I _1b / η) × 100 (%) are 6 or less, Both below 4 were satisfied.

On the other hand, in Comparative Examples 1 to 3 where I ₁ was less than 20, the flexibility was inferior.
In the case of Comparative Example 4 in which the average strength I ₁ was 20 or more but the average strengths I ₇ , I ₁₁ , and I ₁₆ exceeded 1.5, 1.0, and 0.5, respectively, the flexibility was poor.
In all of Comparative Examples 1 to 4, (I ₇ / I ₁ ) × 100 (%) exceeds 8, and (I ₁₁ / I ₁ ) × 100 (%), (I ₁₆ / I ₁ ) × 100 (%) did not satisfy any of 5 or less and 3 or less, respectively.
Further, in each of Comparative Examples 1 to 4, (I _7b / I _1b / η) × 100 (%) exceeds 4 and (I _11b / I _1b / η) × 100 (%), (I _16b / I _1b / η) × 100 (%) did not satisfy any of 6 or less and 4 or less, respectively.

Claims (8)

After heating at 200 ° C. for 0.5 hour, the crystal orientation in the RD direction is displayed in stereo triangle, and this stereo triangle display is divided by 5 degrees each at ω and ψ to display 36 boxes, and the [001] orientation is displayed. Suppose that box number is 1, and ω is large and ψ is large so that the box number increases, and the [111] orientation is box number 36.
(Where ψ is an angle formed by the [100] direction and the RD direction of the sample, ω is a value obtained by tan ω = tan λ · tan ψ, and λ is an angle formed by the [001] direction and the ND direction of the sample. )
And the average intensity _{I 1} of the box number 1 is 20 or more, and an average intensity _I 7 of a corresponding crystal orientations respectively box number _{7,11,16, I 11,} I ₁₆ of 1.5 or less, respectively, 1.0 , Rolled copper foil satisfying any of 0.5 or less. The crystal orientation in the RD direction is displayed as a stereo triangle, and this stereo triangle display is divided into 5 degrees each by ω and ψ to display 36 boxes, the [001] orientation is box number 1, and ω is large below. , And the larger ψ is, the larger the box number is, and when the [111] orientation is the box number 36,
(Where ψ is an angle formed by the [100] direction and the RD direction of the sample, ω is a value obtained by tan ω = tan λ · tan ψ, and λ is an angle formed by the [001] direction and the ND direction of the sample. )
And the average intensity _{I 1} of the box number 1 is 20 or more, and an average intensity _I 7 of a corresponding crystal orientations respectively box number _{7,11,16, I 11,} I ₁₆ of 1.5 or less, respectively, 1.0 , Rolled copper foil satisfying any of 0.5 or less. For the average intensities I ₁ , I ₇ , I ₁₁ , I ₁₆ , (I ₇ / I ₁ ) × 100 (%) is 8 or less, and (I ₁₁ / I ₁ ) × 100 (%), (I The rolled copper foil according to claim 1 or 2, wherein ₁₆ / I ₁ ) x 100 (%) satisfies 5 or less and 3 or less, respectively. The rolled copper foil according to claim 1, wherein I ₇ , I ₁₁ , and I ₁₆ satisfy all of 1.5 or less, 1.0 or less, and 0.5 or less, respectively. The stereo triangle is displayed in a state before the final cold rolling and after the recrystallization annealing, and the box is displayed,
The average intensities of the crystal orientations corresponding to the box numbers 1, ₇ , ₁₁ , and ₁₆ are I _1b , I _7b , I _11b , and I _16b , respectively, and the final cold rolling work degree is η (where η = Ln {(final (Thickness before cold rolling) / (Thickness after final cold rolling)}), (I _7b / I _1b / η) × 100 (%) is 1 or more and 4 or less. The rolled copper foil as described in any one of these. The rolling according to claim 5, wherein (I _11b / I _1b / η) × 100 (%) and (I _16b / I _1b / η) × 100 (%) satisfy any of 6 or less and 4 or less, respectively. Copper foil. The rolled copper foil according to claim 5, wherein η ≧ 2.3. The copper clad laminated board which consists of copper foil as described in any one of Claims 1-7, and resin.