JP2015206616A - Rolled copper foil and manufacturing method of rolled copper foil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a copper-clad laminate and a copper foil having predetermined folding flexural resistance or more by allowing folding flexural resistance estimation to be executed.SOLUTION: The number of folding times of a rolled copper foil is three or more when repeatedly performing : folding in which the rolled copper foil 22 protruded from the edge 11 is folded toward the other main surface 13 of the plate-like member 10 after a rolled copper foil 22 having a resin layer 21 is mounted on one main surface 12 of a plate-like member 10 having a linear edge 11 so that a part of the rolled copper foil 22 is protruded from the edge; adhesion in which the rolled copper foil 22 is adhered to the plate-like member 10 until a total of the thickness of the plate-like member 11, the rolled copper foil 22, and the resin layer 22 at a place where the rolled copper foil 22 exists on both main surfaces 12, 13 of the plate-like member 10 reaches a predetermined value; and folding in which a step of bringing the rolled copper foil 22 brought into contact with the other main surface 13 and a step of folding the rolled copper foil 22 toward one main surface 12 are repeatedly performed until breakage occurrence is recognized.

Description

  The present invention relates to a rolled copper foil and a method for producing the rolled copper foil.

  As a circuit for driving an electronic device such as a digital camera or a mobile phone, a flexible printed circuit (FPC) or a chip of flexible circuit (COF) is used. The FPC and COF are formed by using a copper clad laminate (CCL: Copper Clad Laminate) in which a copper foil is laminated on one or both sides of a resin layer, and forming a circuit pattern (copper wiring) on the copper foil.

  In order to reduce the size and increase the functionality of such an electronic device, a method is adopted in which the FPC is folded and accommodated in a narrow space in the case. For example, in the case of a COF used around a liquid crystal display, the COF on which the copper wiring is formed is folded back to the back side of the liquid crystal substrate in order to make the bezel (so-called “frame”) thin.

  However, there is a problem that when FPC or COF is bent, a large deformation load is applied to the copper foil portion, and the copper foil portion is easily broken. Thus, as a copper foil having a CCL configuration, a rolled copper foil that specifies that the number of times of bending until the copper foil breaks when the 180-degree contact bending is performed is four or more (for example, a patent) Reference 1).

Japanese Patent No. 5124039

  However, in the 180-degree contact bending method described in Patent Document 1, it is important as a test to repeat folding and folding at the same fold position, but in actuality, folding and folding at the same fold position are important. It is difficult to repeat. If the position of the fold is shifted, the number of times until the break as test data increases, the reproducibility as data also deteriorates, and the bending resistance evaluation as CCL may not always be appropriate.

  An object of the present invention is to provide a rolled copper foil that solves the above-described problems and has improved reliability.

  According to one aspect of the present invention, a rolled copper foil provided with a resin layer, the rolled copper foil and the plate-like member on one main surface of a plate-like member having a straight edge at least partially. The rolled copper foil is placed and fixed so that a part of the rolled copper foil protrudes from the edge, and then the rolled copper foil protruding from the edge is placed on the other side of the plate-like member. Folding along the plate member toward the main surface, and the plate member, the rolled copper foil, and the resin layer at the location where the rolled copper foil is present on both main surfaces of the plate member The measured value obtained by measuring the total thickness is a value obtained by doubling the measured value when the thickness of the rolled copper foil and the thickness of the resin layer are individually measured, and the thickness of the plate-like member. Until the rolled copper foil is equal to the total value of the measured values when measured independently. Adhering closely and confirming the presence or absence of breakage of the rolled copper foil located on the side of the plate-like member, if the occurrence of breakage is not observed, so that the rolled copper foil becomes flat, When the rolled copper foil in contact with the other main surface is turned back toward the one main surface and the rolled copper foil is folded back until the occurrence of breakage is observed, until the occurrence of breakage is recognized There is provided a rolled copper foil in which the rolled copper foil is bent a predetermined number of times or more.

  According to another aspect of the present invention, the rolled copper foil provided with a resin layer is in contact with the plate-like member on one main surface of the plate-like member having a straight edge at least partially, and from the edge A placement step of placing and fixing the rolled copper foil so that a part of the rolled copper foil protrudes, and the rolled copper foil protruding from the edge toward the other main surface of the plate-like member Bending along the plate member, and the total thickness of the plate member, the rolled copper foil, and the resin layer at the location where the rolled copper foil is present on both main surfaces of the plate member The measured value obtained by measuring the thickness is a value obtained by doubling the measured value when the thickness of the rolled copper foil and the thickness of the resin layer are individually measured, and the thickness of the plate-like member alone. The rolled copper foil is brought into close contact with the plate-like member until it becomes equal to the total value of the measured value when measured. A step of attaching, a step of confirming whether or not the rolled copper foil located on the side surface of the plate member is broken, and the rolled copper in contact with the other main surface so that the rolled copper foil becomes flat A folding step of folding the rolled copper foil with the foil facing the one main surface, and when the occurrence of breakage is not recognized in the confirmation step, the folding step is performed after the folding step is performed. And the manufacturing method of the rolled copper foil which has the evaluation process which repeats the said contact process and the said confirmation process until the said fracture | rupture generation | occurrence | production is recognized is provided.

  According to the present invention, the reliability of the rolled copper foil can be improved.

It is a schematic sectional drawing of a copper clad laminated board provided with the rolled copper foil concerning one Embodiment of this invention. It is a flowchart which shows the manufacturing process of a copper clad laminated board provided with the rolled copper foil concerning one Embodiment of this invention. It is explanatory drawing of the evaluation method of a copper clad laminated board provided with the rolled copper foil concerning embodiment of this invention, (a) shows a longitudinal cross-sectional schematic diagram, (b) shows a plane schematic diagram. It is explanatory drawing of the evaluation method of the rolled copper foil concerning embodiment of this invention. It is explanatory drawing of the evaluation method of the rolled copper foil concerning embodiment of this invention. It is explanatory drawing of the evaluation method of the rolled copper foil concerning one Example of this invention. It is explanatory drawing of the evaluation method of the rolled copper foil concerning one Example of this invention. It is explanatory drawing of the evaluation method of the rolled copper foil concerning one Example of this invention. It is an image which shows the bending part of the rolled copper foil concerning one Example of this invention. It is an image which shows the bending part of the rolled copper foil concerning one Example of invention. It is an image which shows the bending part of the rolled copper foil concerning one Example of invention. It is an image which shows the bending part of the rolled copper foil concerning one Example of invention.

<One Embodiment of the Present Invention>
(1) Configuration of rolled copper foil and copper clad laminate A rolled copper foil and copper clad laminate 20 according to an embodiment of the present invention will be described below with reference to FIG. FIG. 1 is a schematic cross-sectional view of a copper clad laminate 20 including a rolled copper foil 22 according to this embodiment.

  As shown in FIG. 1, the copper clad laminate 20 according to this embodiment includes a rolled copper foil 22. The rolled copper foil 22 is made of, for example, tough pitch copper (JIS H3100 C1100) or oxygen-free copper (JIS H3100 C1020). The rolled copper foil 22 is formed to have a thickness of, for example, 5 μm or more and 35 μm or less.

  A roughened layer 23 is provided on the main surface of the rolled copper foil 22 on which a resin layer 21 described later is provided. The roughening treatment layer 23 is a layer for forming irregularities on the surface of the rolled copper foil 22 and improving the adhesion between the rolled copper foil 22 and the resin layer 21 by an anchor effect. That is, since the roughening layer 23 can be bitten into the resin layer 21, the mechanical adhesive strength between the rolled copper foil 22 and the resin layer 21 can be improved. The roughening layer 23 is made of, for example, copper (Cu), an alloy of copper and nickel (Cu—Ni alloy), an alloy of copper and cobalt (Cu—Co alloy) (plated particles), or the like.

  The copper-clad laminate 20 includes two rolled copper foils 22a and 22b, and a resin layer 21 is provided between the rolled copper foil 22a and the rolled copper foil 22b. That is, the rolled copper foils 22a and 22b are provided on both main surfaces of the resin layer 21, respectively. The rolled copper foils 22a and 22b are provided such that the roughening treatment layer 23 and the resin layer 21 are in contact with each other. The resin layer 21 is formed of a polyimide (PI) film, a polyester film such as polyethylene terephthalate (PET), or the like. The resin layer 21 is formed to have a thickness of, for example, 10 μm or more and 60 μm or less.

(2) Manufacturing Method of Rolled Copper Foil and Copper Clad Laminate Next, an embodiment of a manufacturing method of the rolled copper foil 22 and the copper clad laminate 20 according to the present embodiment will be described with reference to FIGS. To do. FIG. 2 is a flow diagram showing a manufacturing process of the rolled copper foil and the copper clad laminate provided with the rolled copper foil according to the present embodiment. 3-5 is explanatory drawing of the evaluation method of a copper clad laminated board provided with the rolled copper foil concerning this embodiment, respectively.

(Casting process (S11))
As shown in FIG. 2, first, for example, tough pitch copper or oxygen-free copper is melted by, for example, a high-frequency melting furnace to form a molten copper. The molten copper is poured into a mold and cooled to cast (ingot) a predetermined shape ingot.

(Hot rolling process (S12))
After the casting step (S11) is completed, the ingot is heated to a predetermined temperature (for example, 950 ° C.) and subjected to hot rolling to form a hot rolled material having a predetermined thickness (for example, 12 mm).

(Primary cold rolling / primary annealing treatment step (S13))
After the hot rolling step (S12) is completed, the primary cold rolling treatment and the primary annealing treatment are alternately repeated a predetermined number of times on the hot rolled material, and a predetermined thickness (for example, 0.1 mm to 1 mm). The first cold rolled material is formed.

(Secondary annealing treatment step (S14))
After the primary cold rolling / primary annealing treatment step (S13) is completed, the primary cold rolling material is subjected to a secondary annealing treatment to form a secondary annealing material.

(Rolled copper foil forming step (S15))
After the secondary annealing treatment step (S14) is finished, the secondary annealing material is subjected to secondary cold rolling treatment (final cold rolling treatment, finish rolling treatment), and a predetermined thickness (for example, 5 μm or more and 35 μm or less). A rolled copper foil 22 is formed. As the secondary cold rolling treatment, for example, using a rolling roll, rolling in the secondary cold rolling treatment without changing the length of the secondary annealing material in the direction orthogonal to the rolling direction (the width direction of the secondary annealing material). The process of reducing the thickness of the secondary annealing material is performed a plurality of times while increasing the length of the secondary annealing material in the direction (that is, extending the secondary annealing material in the rolling direction).

(Roughening treatment layer forming step (S16))
After the rolled copper foil forming step (S15) is completed, the surface of the rolled copper foil 22 on which the resin layer 21 is to be formed is roughened to form the roughened layer 23 on the rolled copper foil 22. To do. A roughening process is a process which performs the electroplating (electrolytic plating) process, for example, and forms the layer which consists of a plating particle (roughening grain) of a predetermined | prescribed average particle diameter.

(Resin layer forming step (S17))
After the roughening treatment layer forming step (S16) is completed, the resin layer 21 is formed on the rolled copper foil 22. First, a resin film such as a polyimide (PI) film as the resin layer 21 or a polyester film such as polyethylene terephthalate (PET) is prepared. Then, the rolled copper foils 22a and 22b are placed on both main surfaces of the resin layer 21 so that the resin layer 21 having a predetermined thickness (for example, 10 μm or more and 60 μm or less) and the roughening treatment layer 23 are in contact with each other, The rolled copper foils 22a and 22b and the resin layer 21 are bonded together. As a method of bonding the rolled copper foils 22a and 22b and the resin layer 21, respectively, for example, a method of bonding using an adhesive can be used. After bonding the rolled copper foils 22a and 22b and the resin layer 21 respectively, the rolled copper foils 22a and 22b are subjected to a recrystallization annealing treatment, and the copper having the rolled copper foils 22a and 22b provided on both surfaces of the resin layer 21 A tension laminate (double-sided CCL) 20 is formed.

(Evaluation process (S20))
When the resin layer forming step (S17) is completed, the rolled copper foil 22 (copper-clad laminate 20) including the resin layer 21 is cut into a predetermined shape (for example, 5 mm in width and 90 mm in length), and bending evaluation is performed on the rolled copper foil 22. Do.

[Placing step (S21)]
First, as shown in FIGS. 3 (a) and 3 (b), one main surface 12 of a plate-like member (spacer) 10 having a straight edge 11 at least partially and having a predetermined thickness (for example, 0.02 mm). The copper clad laminate 20 is placed on the top. At this time, the copper-clad laminate is such that the plate-like member 10 and the rolled copper foil 22 (rolled copper foil 22a) are in contact with each other, and a part of the copper-clad laminate 20 protrudes from the straight edge 11 of the plate-like member 10. 20 is placed on the plate member 10. And the copper clad laminated board 20 mounted on the plate-shaped member 10 is fixed, for example with an adhesive tape.

[Bending process (S22)]
When the placing step (S21) is completed, the copper clad laminate 20 protruding from the straight edge 11 is directed along the plate member 10 toward the other main surface 13 of the plate member 10, as shown in FIG. And bend. And the rolled copper foil 22 (rolled copper foil 22a) is made to contact on the other main surface 13 of the plate-shaped member 10, as shown in FIG.

[Adherence Step (S23)]
When the bending step (S22) is completed, the plate member 10 and the copper clad laminate 20 (rolled copper foil 22a) are formed so that no gap is formed between the plate member 10 and the rolled copper foil 22 (rolled copper foil 22a). ). Specifically, first, the plate-like member 10 and the copper-clad laminate 20 (the rolled copper foil 22 and the resin layer 21 in the place where the copper-clad laminate 20 exists on both main surfaces 12 and 13 of the plate-like member 10. ) And a total thickness (hereinafter also referred to simply as “total thickness”) using a thickness measuring device (for example, a micrometer). And this total thickness is a measured value t ₁ when the thickness of the rolled copper foil 22 and the thickness of the resin layer 21 are each measured independently (when the thickness of the copper clad laminate 20 is measured alone). Until the total value (2t ₁ + t ₂ ) of the value obtained by doubling the value (2t ₁ ) and the measured value t ₂ when the thickness of the plate-like member 10 is independently measured is equal to The copper clad laminate 20 (rolled copper foil 22a) is brought into close contact with the plate member 10 using For example, using a micrometer that can numerically control the distance between the thickness measurement units, the plate member 10 and the copper clad laminate 20 are brought into close contact until the scale of the micrometer reaches 2t ₁ + t ₂ . In addition, the single thickness of the rolled copper foil 22, the single thickness of the resin layer 21, and the single thickness of the plate member 10 can each be measured by a thickness measuring device.

[Confirmation step (S24)]
When the adhesion step (S23) is completed, the bent portion of the rolled copper foil 22 is observed by, for example, an optical microscope (optical lens 4 times) to confirm whether or not the bent portion is broken. That is, it is confirmed whether or not the rolled copper foil 22 located on the side surface 14 of the plate-like member 10 is broken. For example, when cracks (cracks or cracks) or the like are recognized on the surface of the bent portion of the rolled copper foil 22, “break” is set, and when no cracks are found, “no break” is set.

[Folding step (S25)]
When the occurrence of breakage is not recognized in the confirmation step (S24) (that is, it is determined that “no breakage”), the copper clad laminate 20 is flattened (that is, until the state shown in FIG. 3 is reached). A rolled copper foil 22 (that is, a copper clad laminate 20 located on the other main surface 13 side of the plate-like member 10) in contact with the other main surface 13 of the plate-shaped member 10 is directed to one main surface 12 with a jig ( For example, it is folded using a micrometer.

  After the folding process (S25) is finished, the folding process (S22), the adhesion process (S23), the confirmation process (S24), and the folding process (S25) are repeated until occurrence of breakage is recognized in the confirmation process (S24). .

[Bending Count Calculation Step (S26)]
When breakage is recognized in the confirmation step (S24) (that is, it is determined that there is a break), the number of bendings performed until the occurrence of breakage in the rolled copper foil 22 (rolled copper foil 22b) is calculated. To do. For example, the number of bending processes (S22) performed until the occurrence of breakage in the rolled copper foil 22 is recognized is calculated.

(3) Effects According to the Present Embodiment According to the present embodiment, one or a plurality of effects described below are exhibited.

(A) In this embodiment, according to the evaluation method of the rolled copper foil 22, bending and folding are repeatedly performed at the same location of the rolled copper foil 20. Therefore, the reliability of the evaluation result can be improved.

  For example, when the thickness of the rolled copper foil 22 is 6 μm, the number of bendings is 2 or more. When the thickness of the rolled copper foil 22 is 9 μm, the number of bendings is 3 or more. When the thickness of the rolled copper foil 22 is 12 μm, the number of bendings is 4 or more. When the thickness of the rolled copper foil 22 is 18 μm, the number of bendings is 5 or more.

(B) In this embodiment, the rolled copper foil 22 is evaluated by fixing the rolled copper foil 22 (copper-clad laminate 20) on the plate member 10 with, for example, an adhesive tape. Thereby, when the rolled copper foil 22 (copper-clad laminate 20) is bent or folded, the position of the rolled copper foil 22 (copper-clad laminate 20) can be suppressed from shifting on the plate-like member 10. Therefore, the effect (a) can be further obtained.

(C) In this embodiment, in the rolled copper foil forming step, the secondary cold rolling process is performed as a secondary cold rolling process without changing the length of the secondary annealing material in the direction orthogonal to the rolling direction. The process of reducing the thickness of the secondary annealing material is performed a plurality of times while increasing the length of the secondary annealing material in the direction (that is, extending the secondary annealing material in the rolling direction). Thereby, the orientation degree of the crystal structure with respect to the rolling direction by the secondary cold rolling treatment can be increased. When the folding and folding of the rolled copper foil are repeated, microscopic strains are concentrated and accumulated at the locations where the crystal structure is not oriented. By increasing the degree of orientation of the crystal structure, it is possible to delay the accumulation of strain in the rolled copper foil. As a result, the bending resistance of the rolled copper foil can be improved. That is, the occurrence of breakage of the rolled copper foil 22 can be suppressed. Therefore, when the bendability is evaluated by the evaluation method (a), the number of bendings until the rolled copper foil is ruptured can be made a predetermined number or more.

  For example, when the thickness of the rolled copper foil 22 is 6 μm, the number of bendings can be made 2 times or more. When the thickness of the rolled copper foil 22 is 9 μm, the number of bending can be increased to 3 times or more. When the thickness of the rolled copper foil 22 is 12 μm, the number of bendings can be increased to 4 times or more. When the thickness of the rolled copper foil 22 is 18 μm, the number of bending can be made 5 times or more.

(Other embodiments)
As mentioned above, although one Embodiment of this invention was described concretely, this invention is not limited to the above-mentioned embodiment, In the range which does not deviate from the summary, it can change suitably.

  In the above-described embodiment, the copper clad laminate 20 in which the rolled copper foil 22 is provided on both surfaces of the resin layer 21 has been described. However, the present invention is not limited to this. For example, the copper clad laminated board (single-sided CCL) 20 by which the rolled copper foil 22 was provided in any main surface of the resin layer 21 may be sufficient. In this case, when performing an evaluation process (S20), the copper clad laminated board 20 is made into the plate-shaped member 10 so that the rolled copper foil 22 may become an outer side (namely, the resin layer 21 and the plate-shaped member 10 may contact | connect). It is better to place it on top. Moreover, not a copper clad laminated board but a rolled copper foil single-piece | unit may be sufficient.

  In addition, when setting it as CCL structure, about the thickness of the resin layer 21 and the thickness of the plate-shaped member 10, it is not limited to the value mentioned above. When the thickness of the resin layer 21 and the thickness of the plate-like member 10 are thinner than 0.2 mm, the number of times of bending until the fracture is recognized in the rolled copper foil 22 is reduced as compared with the above-described embodiment. Like the form, the reliability of the rolled copper foil 22 can be improved.

  In the above-described embodiment, the case where the roughening treatment layer 23 is provided on the rolled copper foil 22 has been described, but the roughening treatment layer 23 may not be provided.

Moreover, in the above-mentioned embodiment, although the bonding of the rolled copper foil 22 and the resin layer 21 was performed using the adhesive agent, it is not limited to this. For example, bonding may be performed by bonding the rolled copper foil 22 and the resin layer 21 under high temperature and high pressure without using an adhesive. Moreover, in the above-mentioned embodiment, although the resin film was used as the resin layer 21, it is not limited to this. For example, after applying a polyimide precursor onto the rolled copper foil 22 (roughening layer 23), the polyimide precursor is dried and cured to form the resin layer 21, thereby forming the rolled copper foil 22 and the resin layer 21. And may be pasted together.

Example 1
After casting a tough pitch copper ingot, a hot rolled material having a thickness of 12 mm was obtained by hot rolling. Subsequently, a primary cold rolled material was produced by repeating a primary cold rolling process and a primary annealing process on the hot rolled material. The obtained primary cold-rolled material is 0.1 mm thick × 600 mm wide × 10 m long. A secondary annealing treatment was performed on the primary cold-rolled material to produce a secondary annealed material. And the secondary cold rolling process was performed to the secondary annealing material. Specifically, using the rolling roll, without changing the length of the secondary annealing material in the direction orthogonal to the rolling direction, while extending the secondary annealing material in the rolling direction, the thickness of the secondary annealing material is reduced. The process was repeated 12 times. This produced the rolled copper foil of the shape of thickness 17micrometer x width 600mm x length 50m.

  A roughened layer was formed on one main surface of the rolled copper foil to form a roughened layer, and a surface-treated copper foil having a thickness of 18 μm was produced. Hereinafter, the rolled copper foil on which the roughened layer is formed is referred to as a surface-treated copper foil. After that, a surface-treated copper foil is bonded to both sides of a polyimide resin with a thickness of 25 μm, and a recrystallized annealing treatment is performed on the surface-treated copper foil (rolled copper foil) to form a double-sided copper-clad laminate (double-sided CCL). Produced.

(Evaluation method)
In order to evaluate the bending resistance of the rolled copper foil, 5 pieces were cut out from the double-sided CCL to a width of 5 mm and a length of 90 mm, and these were designated as samples n1 to n5, respectively. For example, as shown in FIG. 6, a plate-like member having a thickness of 0.2 mm was fixed to a CCL having a thickness t ₁ (mm) with an adhesive tape. Then, for example, as shown in FIG. 7, the CCL was bent using a micrometer so that the gap = t ₂ + 2 × t ₁ . And the bending part (fold) of rolled copper foil was observed with the optical microscope, and the presence or absence of the fracture | rupture generation | occurrence | production of rolled copper foil was observed. Then, as shown in FIG. 8, the rolled copper foil (CCL) was folded using a micrometer until the state shown in FIG. 6 was obtained.

  By repeating this operation, the number of times of bending until the fracture occurred in the bent portion of the rolled copper foil was measured. FIG. 9 shows an image obtained by observing the bent portion of the sample n1 with the number of bendings 3 times with an optical microscope, and FIG. 10 shows an image obtained by observing the bent portion with the sample n1 with the number of folding times 4 times with the optical microscope. FIG. 11 shows an image obtained by observing the bent portion of the sample n1 with the folding number of 5 times with an optical microscope, and FIG. 12 shows an image obtained by observing the bent portion of the sample n1 with the number of folding times of 6 with the optical microscope. From FIG. 9 to FIG. 12, it can be confirmed that the rolled copper foil is broken from the fifth folding. Therefore, the number of bendings until the fracture occurred in the rolled copper foil was determined to be 5 times. Such measurement evaluation was performed with five samples.

  In Table 1, the frequency | count of bending until a fracture | rupture generate | occur | produces in the rolled copper foil of Example 1 is shown. As shown in Table 1, the average number of times of bending is 5.6 times, the variation in measurement is less than ± 1, the measurement accuracy is also satisfactory, the number of times of bending is 5 times or more, and the copper foil thickness is 18 μm. It was judged that it was a rolled copper foil that was favorable for bending FPC.

(Example 2)
A secondary cold rolling treatment was performed on the secondary annealed material produced in the same manner as in Example 1. Specifically, using a rolling roll, the process of reducing the thickness of the secondary annealing material was repeated 14 times while extending the secondary annealing material in the rolling direction. This produced the rolled copper foil of the shape of thickness 11micrometer x width 600mm x length 50m. A roughened layer was formed on one main surface of the rolled copper foil to form a roughened layer, and a surface-treated copper foil having a thickness of 12 μm was produced. And double-sided CCL was produced.

  A bending test was performed in the same manner as in Example 1. Table 1 shows the number of bendings until breakage occurs in the rolled copper foil of Example 2. As shown in Table 1, the average number of bendings is 4.6 times, the variation in measurement is about ± 1, the measurement accuracy is satisfactory, the bending resistance is 4 times or more, and the copper foil thickness is 12 μm. It was judged that it was a good rolled copper foil for use in bending FPC.

(Example 3)
Secondary cold rolling treatment was performed on the secondary annealed material produced in the same manner as in Example 1. Specifically, as the secondary cold rolling process, by using a rolling roll, the process of reducing the thickness of the secondary annealing material while repeating the secondary annealing material in the rolling direction is repeated 16 times. It was. This produced the rolled copper foil of the shape of thickness 8micrometer x width 600mm x length 50m. A roughened layer was formed on one main surface of the rolled copper foil to form a roughened layer, thereby producing a surface-treated copper foil having a thickness of 9 μm. And double-sided CCL was produced.

  A bending test was carried out in the same manner as in Example 1. Table 1 shows the number of times of bending until breakage occurs in the rolled copper foil of Example 3. As shown in Table 1, the average number of bendings is 3.6 times, the measurement variation is about ± 1, the measurement accuracy is satisfactory, the bending resistance is 3 times or more, and the copper foil thickness is 9 μm. It was judged that it was a good rolled copper foil for use in bending FPC.

Example 4
The secondary annealing material produced in the same manner as in Example 1 was repeated 18 times using a rolling roll and extending the secondary annealing material in the rolling direction while reducing the thickness of the secondary annealing material. It was. Thereby, a rolled copper foil having a shape of thickness 5.5 μm × width 600 mm × length 50 m was produced. A roughened layer was formed on one main surface of the rolled copper foil to form a roughened layer, and a surface-treated copper foil having a thickness of 6 μm was produced. And double-sided CCL was produced.

  A bending test was carried out in the same manner as in Example 1. Table 1 shows the number of bendings until breakage occurs in the rolled copper foil of Example 4. As shown in Table 1, the average number of bendings is 3.0 times, the measurement variation is about ± 1, the measurement accuracy is satisfactory, the bending resistance is 2 times or more, and the copper foil thickness is 6 μm. It was judged that it was a good rolled copper foil for use in bending FPC.

(Comparative Example 1)
A secondary cold rolling process was performed on a secondary annealed material having a thickness of 0.1 mm, a width of 600 mm, and a length of 500 mm produced in the same manner as in Example 1, using a rolling roll. As the secondary cold rolling treatment, rolling processing (hereinafter also referred to as “WD processing”) in which the length in the direction (width direction) orthogonal to the rolling direction of the secondary annealing material is increased, and rolling of the secondary annealing material are performed. The rolling process in which the length in the direction becomes longer (hereinafter also referred to as “TD process”) was alternately repeated, and a total of 12 rolling processes were performed. Thereby, a rolled copper foil having a thickness of 17 μm was produced. A roughened layer was formed on any main surface of the rolled copper foil to form a roughened layer, thereby producing a surface-treated copper foil having a thickness of 18 μm. And double-sided CCL was produced.

  A bending test was carried out in the same manner as in Example 1. Table 1 shows the number of times that the rolled copper foil of Comparative Example 1 is bent until breakage occurs. As shown in Table 1, the average number of bendings was 4.6 times, the measurement variation was about ± 1, and the measurement accuracy was judged to be satisfactory, but the bending resistance was less than 4 times, and CCL It was judged that the copper foil had a problem in bending resistance. This is presumed to be because the rolling process was performed alternately with the WD process and the TD process.

(Comparative Example 1b)
A double-sided CCL was produced using the rolled copper foil produced in Comparative Example 1 described above. In the folding test, the plate-like member and the CCL are not fixed with the adhesive tape, but the method of repeating folding and folding at the same fold by hand causes breakage in the rolled copper foil with 5 samples. The number of bending until was examined.

  As shown in Table 1, the average number of bendings was 6.6 times, and the measurement variation was about 2 ± times. As described above, when the test is performed without fixing the CCL and the plate-like member, not only the measurement variation increases, but also the measurement value itself increases. This is presumed to be because the plate-like member and the copper foil are not fixed when the folding and the folding are repeated, so that the position of the fold is shifted each time the folding is performed. Although this copper foil is the same as that of Comparative Example 1 and is regarded as defective as a quality, such a test method is judged as a non-defective product, which indicates that there is a problem in measurement.

(Comparative Example 2)
A secondary cold rolling process was performed on a secondary annealed material having a thickness of 0.1 mm, a width of 600 mm, and a length of 500 mm produced in the same manner as in Example 1, using a rolling roll. As the secondary cold rolling treatment, WD processing and TD processing were alternately performed repeatedly, and a total of 14 rolling processes were performed. Thereby, a rolled copper foil having a thickness of 11 μm was produced. In the same manner as in Example 2, a roughened layer was formed on any main surface of the rolled copper foil to form a roughened layer, and a surface-treated copper foil having a thickness of 12 μm was produced. And double-sided CCL was produced.

  A bending test was carried out in the same manner as in Example 1. Table 1 shows the number of bendings until the rolled copper foil of Comparative Example 2 breaks. As shown in Table 1, the average number of bendings was 3.6 times, the measurement variation was about ± 1 time, and it was judged that the measurement accuracy was satisfactory, but the bending resistance was less than 4 times, and CCL It was judged that the copper foil had a problem in bending resistance. This is considered to be an inappropriate manufacturing method in which the rolling process is alternately performed by the WD process and the TD process.

(Comparative Example 3)
A secondary cold rolling process was performed on a secondary annealed material having a thickness of 0.1 mm, a width of 600 mm, and a length of 500 mm produced in the same manner as in Example 1, using a rolling roll. As the secondary cold rolling treatment, WD processing and TD processing were alternately performed repeatedly, and a total of 16 rolling operations were performed. As a result, a rolled copper foil having a thickness of 8 μm was produced. In the same manner as in Example 3, a roughened layer was formed on any main surface of the rolled copper foil to form a roughened layer, and a surface-treated copper foil having a thickness of 9 μm was produced. And double-sided CCL was produced.

  A bending test was carried out in the same manner as in Example 1. Table 1 shows the number of bendings until the breakage occurs in the rolled copper foil of Comparative Example 3. As shown in Table 1, the average number of bendings was 2.6 times, the measurement variation was about ± 1, and the measurement accuracy was judged to be satisfactory, but the bending resistance was less than 3 times, and CCL It was judged that the copper foil had a problem in bending resistance. This is presumably because rolling WD processing and TD processing were performed alternately.

(Comparative Example 4)
A secondary cold rolling process was performed on a secondary annealed material having a thickness of 0.1 mm, a width of 600 mm, and a length of 500 mm produced in the same manner as in Example 1, using a rolling roll. As the secondary cold rolling treatment, WD processing and TD processing were alternately performed repeatedly, and a total of 18 rolling operations were performed. This produced the rolled copper foil of thickness 5.5 micrometers. In the same manner as in Example 4, a roughened layer was formed on any main surface of the rolled copper foil to form a roughened layer, thereby producing a surface-treated copper foil having a thickness of 6 μm. And double-sided CCL was produced.

  A bending test was carried out in the same manner as in Example 1. In Table 1, the frequency | count of bending until a fracture | rupture generate | occur | produces in the rolled copper foil of the comparative example 4 is shown. As shown in Table 1, the average number of bendings was 1.6 times, the measurement variation was about ± 1, and the measurement accuracy was judged to be satisfactory, but the bending resistance was less than 2 times, and CCL It was judged that the copper foil had a problem in bending resistance. This is presumed to be because the rolling process was performed alternately with the WD process and the TD process.

<Preferred embodiment of the present invention>
Hereinafter, preferred embodiments of the present invention will be additionally described.

[Appendix 1]
According to one aspect of the invention,
A rolled copper foil provided with a resin layer,
The rolled copper foil and the plate-like member are in contact with one main surface of the plate-like member having a straight edge at least partially, and the rolled copper foil protrudes from the edge, After placing and fixing the rolled copper foil,
Bending the rolled copper foil protruding from the edge toward the other main surface of the plate-like member along the plate-like member;
The measured value obtained by measuring the total thickness of the plate member, the rolled copper foil, and the resin layer at the location where the rolled copper foil is present on both main surfaces of the plate member is the rolled copper foil. Is equal to the value obtained by doubling the measured value when the thickness of the resin layer and the thickness of the resin layer are individually measured, and the total value of the measured values when the thickness of the plate-like member is independently measured. Until the contact, close contact the rolled copper foil to the plate member,
Check the presence or absence of breakage of the rolled copper foil located on the side surface of the plate-like member, and if the occurrence of breakage is not observed, the other main surface and the other main surface so that the rolled copper foil becomes flat Folding back the rolled copper foil with the rolled copper foil in contact with the one main surface;
When repeated until the occurrence of breakage is observed,
There is provided a rolled copper foil in which the rolled copper foil is bent a predetermined number of times or more until the occurrence of breakage is recognized.

[Appendix 2]
The rolled copper foil of Appendix 1, preferably,
The rolled copper foil is formed to have a thickness of 5 μm or more and 35 μm or less.

[Appendix 3]
The rolled copper foil of Appendix 1, preferably,
When the thickness of the rolled copper foil is 9 μm, the number of bending is 3 or more.

[Appendix 4]
The rolled copper foil of Appendix 1, preferably,
When the thickness of the rolled copper foil is 12 μm, the number of bendings is 4 times or more.

[Appendix 5]
The rolled copper foil of Appendix 1, preferably,
When the thickness of the rolled copper foil is 18 μm, the number of bendings is 5 or more.

[Appendix 6]
According to another aspect of the invention,
A process of forming a primary cold rolled material by performing a primary cold rolling process and a primary annealing process a predetermined number of times on a hot rolled material formed by performing a hot rolling process on a copper ingot, and the primary cold rolling By performing a secondary annealing treatment on the material to form a secondary annealing material, and a secondary cold rolling treatment on the secondary annealing material to form a rolled copper foil. Manufactured,
Without changing the length of the secondary annealing material in the direction orthogonal to the rolling direction, the secondary annealing material is extended in the rolling direction of the secondary cold rolling process, and the thickness of the secondary annealing material is reduced. A rolled copper foil formed by performing the secondary cold rolling process a plurality of times is provided.

[Appendix 7]
The rolled copper foil according to any one of appendices 1 to 6, preferably,
On the surface of the rolled copper foil on which the resin layer is provided, a roughening treatment layer formed of a plurality of plating particles is provided.

[Appendix 8]
According to yet another aspect of the invention,
The rolled copper foil provided with a resin layer is in contact with the plate-like member on one main surface of the plate-like member having at least a straight edge, and a part of the rolled copper foil protrudes from the edge. A mounting step of mounting and fixing the rolled copper foil;
Bending the rolled copper foil protruding from the edge along the plate member toward the other main surface of the plate member;
The measured value obtained by measuring the total thickness of the plate member, the rolled copper foil, and the resin layer at the location where the rolled copper foil is present on both main surfaces of the plate member is the rolled copper foil. The total value of the value obtained by doubling the measured value when the thickness of the resin layer and the thickness of the resin layer are individually measured, and the measured value when the thickness of the plate-like member is independently measured Until the rolled copper foil is in close contact with the plate-like member until equal to
A confirmation step for confirming the presence or absence of breakage of the rolled copper foil located on the side surface of the plate-like member;
A folding step of folding back the rolled copper foil with the rolled copper foil in contact with the other main surface facing the one main surface, so that the rolled copper foil becomes flat,
When the occurrence of breakage is not recognized in the confirmation step, after the folding step, the bending step, the adhesion step, and the confirmation step are repeated until the breakage is recognized. A method for producing a rolled copper foil having a process is provided.

[Appendix 9]
According to yet another aspect of the invention,
A process of forming a primary cold rolled material by performing a primary cold rolling process and a primary annealing process a predetermined number of times on a hot rolled material formed by performing a hot rolling process on a copper ingot;
A step of subjecting the primary cold-rolled material to a secondary annealing treatment to form a secondary annealing material;
The secondary annealing material has a step of performing a secondary cold rolling process to form a rolled copper foil,
In the secondary cold rolling process, without changing the length of the secondary annealing material in the direction orthogonal to the rolling direction, while extending the secondary annealing material in the rolling direction of the secondary cold rolling process, A method for producing a rolled copper foil is provided in which the treatment for reducing the thickness of the secondary annealing material is performed a plurality of times.

[Appendix 10]
According to yet another aspect of the invention,
The rolled copper foil provided with a resin layer and the plate-like member are in contact with one main surface of the plate-like member having at least a straight edge, and a part of the rolled copper foil protrudes from the edge. A mounting step of mounting and fixing the rolled copper foil;
Bending the rolled copper foil protruding from the edge along the plate member toward the other main surface of the plate member;
The measured value obtained by measuring the total thickness of the plate member, the rolled copper foil, and the resin layer at the location where the rolled copper foil is present on both main surfaces of the plate member is the rolled copper foil. The total value of the value obtained by doubling the measured value when the thickness of the resin layer and the thickness of the resin layer are individually measured, and the measured value when the thickness of the plate-like member is independently measured Until the rolled copper foil is in close contact with the plate-like member until equal to
A confirmation step for confirming the presence or absence of breakage of the rolled copper foil located on the side surface of the plate-like member;
Folding the rolled copper foil until the rolled copper foil is flattened, with the rolled copper foil in contact with the other principal surface facing the one principal surface,
When the occurrence of breakage is not recognized in the confirmation step, after performing the folding step, the rolling step, the adhesion step, and the confirmation step are repeatedly performed until the occurrence of breakage is recognized. A method for evaluating copper foil is provided.

[Appendix 11]
According to yet another aspect of the invention,
The rolled copper foil according to any one of appendices 1 to 7,
There is provided a copper clad laminate comprising a resin layer provided on any main surface of the rolled copper foil.

DESCRIPTION OF SYMBOLS 10 Plate-shaped member 11 Straight edge 12 One surface 13 of plate-shaped member The other surface 20 of a plate-shaped member 20 Copper-clad laminate 21 Resin layer 22 (22a, 22b) Rolled copper foil

Claims (5)

A rolled copper foil provided with a resin layer,
The rolled copper foil and the plate-like member are in contact with one main surface of the plate-like member having a straight edge at least partially, and the rolled copper foil protrudes from the edge, After placing and fixing the rolled copper foil,
Bending the rolled copper foil protruding from the edge toward the other main surface of the plate-like member along the plate-like member;
The measured value obtained by measuring the total thickness of the plate member, the rolled copper foil, and the resin layer at the location where the rolled copper foil is present on both main surfaces of the plate member is the rolled copper foil. Is equal to the value obtained by doubling the measured value when the thickness of the resin layer and the thickness of the resin layer are individually measured, and the total value of the measured values when the thickness of the plate-like member is independently measured. Until the contact, close contact the rolled copper foil to the plate member,
Check the presence or absence of breakage of the rolled copper foil located on the side surface of the plate-like member, and if the occurrence of breakage is not observed, the other main surface and the other main surface so that the rolled copper foil becomes flat Folding back the rolled copper foil with the rolled copper foil in contact with the one main surface;
When repeated until the occurrence of breakage is observed,
A rolled copper foil in which the rolled copper foil is bent a predetermined number of times or more until the occurrence of breakage is recognized. 2. The rolled copper foil according to claim 1, wherein when the thickness of the rolled copper foil is 9 μm, the number of bending times is 3 or more. 2. The rolled copper foil according to claim 1, wherein when the rolled copper foil has a thickness of 12 μm, the number of bendings is 4 or more. 2. The rolled copper foil according to claim 1, wherein when the rolled copper foil has a thickness of 18 μm, the number of bendings is 5 or more. The rolled copper foil provided with a resin layer is in contact with the plate-like member on one main surface of the plate-like member having at least a straight edge, and a part of the rolled copper foil protrudes from the edge. A mounting step of mounting and fixing the rolled copper foil;
Bending the rolled copper foil protruding from the edge along the plate member toward the other main surface of the plate member;
The measured value obtained by measuring the total thickness of the plate member, the rolled copper foil, and the resin layer at the location where the rolled copper foil is present on both main surfaces of the plate member is the rolled copper foil. The total value of the value obtained by doubling the measured value when the thickness of the resin layer and the thickness of the resin layer are individually measured, and the measured value when the thickness of the plate-like member is independently measured Until the rolled copper foil is in close contact with the plate-like member until equal to
A confirmation step for confirming the presence or absence of breakage of the rolled copper foil located on the side surface of the plate-like member;
A folding step of folding back the rolled copper foil with the rolled copper foil in contact with the other main surface facing the one main surface, so that the rolled copper foil becomes flat,
When the occurrence of breakage is not recognized in the confirmation step, after the folding step, the bending step, the adhesion step, and the confirmation step are repeated until the breakage is recognized. The manufacturing method of the rolled copper foil which has a process.