Manufacturing method of copper clad laminate

Abstract

To provide a manufacturing method for obtaining a copper clad laminate with a slight flare.SOLUTION: The manufacturing method for a copper clad laminate includes cutting a raw copper clad laminate into a first cut processed product, a hollow part, and a second cut processed product with a gang-cut type cutter unit. A preferred draw-out angle of the hollow part is -20° to 0°. A preferred take-up tension of the first cut processed product is 30 to 60 N. A preferred draw-out angle of the first cut processed product is 0° to 6°. Since the copper clad laminate is cut with a gang-cut type cutter unit, a copper clad laminate with slight flare can be obtained.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a method for producing a copper clad laminate, and more particularly to a method for cutting a wide copper clad laminate to obtain a copper clad laminate having a desired width. [Background technology]

[0002] Flexible printed wiring boards, which have wiring patterns formed on the surface of a resin film, are used in electronic devices such as liquid crystal panels, laptops, digital cameras, and mobile phones. Flexible printed wiring boards are obtained by forming wiring patterns on copper-clad laminates using methods such as semi-additive and subtractive processes.

[0003] Copper-clad laminates are manufactured in a wide state, and then cut into narrower widths using a slitter to facilitate wiring processing. In this process, the edges of the copper-clad laminate after cutting may become wavy (also known as flared) (Patent Documents 1 and 2). Flared edges are particularly likely to occur when the copper-clad laminate is thin and easily stretched.

[0004] One of the causes of flaring is burrs that form on the cut edges. If copper-clad laminate is wound into a roll while burrs remain, the burrs on the edges will accumulate and become high edges. This can cause wrinkles in long rolls. It can also make the roll less transportable, reducing production efficiency. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 10-64527 [Patent Document 2] Japanese Patent Application Laid-Open No. 2013-10718 Summary of the Invention [Problem to be solved by the invention]

[0006] In view of the above circumstances, an object of the present invention is to provide a manufacturing method that can produce a copper-clad laminate with small flare. [Means for solving the problem]

[0007] The method for producing a copper clad laminate of the present invention is characterized in that a raw copper clad laminate is cut into a first cut product, a hollowed portion, and a second cut product using a gang cut type cutter unit. [Effects of the Invention]

[0008] According to the present invention, the copper clad laminate is cut by a gang cut type cutter unit, so that a copper clad laminate with small flare can be obtained. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a cross-sectional view of a copper-clad laminate. [Figure 2] FIG. [Figure 3] 10 is an explanatory diagram of the pull-out angle of the first cut product and the pull-out angle of the hollowed-out portion. FIG. [Figure 4] FIG. DETAILED DESCRIPTION OF THE INVENTION

[0010] Next, an embodiment of the present invention will be described with reference to the drawings. As shown in Fig. 1, the copper clad laminate 1 comprises a base film 10 and a copper layer 20 formed on the surface of the base film 10. The copper layer 20 may be formed on only one side of the base film 10 as shown in Fig. 1, or the copper layer 20 may be formed on both sides of the base film 10.

[0011] A resin film such as a polyimide film or a liquid crystal polymer (LCP) film can be used as the base film 10. The copper layer 20 is made up of a metal layer 21 formed by a dry film formation method such as sputtering, and a copper plating film 22 formed by electrolytic plating. The metal layer 21 and the copper plating film 22 are laminated in this order on the surface of the base film 10.

[0012] The metal layer 21 is made of a metal underlayer 21a and a copper thin film layer 21b. The metal underlayer 21a and the copper thin film layer 21b are laminated in this order on the surface of the base film 10. The metal underlayer 21a is generally made of nickel, chromium, or a nickel-chromium alloy. The metal underlayer 21a is not necessary. The copper thin film layer 21b may be formed on the surface of the base film 10 via the metal underlayer 21a, or may be formed directly on the surface of the base film 10 without the metal underlayer 21a.

[0013] Although not particularly limited, the thickness of the base film 10 is generally 10 to 40 μm. The thickness of the underlying metal layer 21a is generally 5 to 50 nm, and the thickness of the copper thin film layer 21b is generally 50 to 400 nm. The thickness of the copper plating film 22 is generally 8 to 12 μm in the case of a copper clad laminate 1 processed by a subtractive method, and generally 0.1 to 5 μm in the case of a copper clad laminate 1 processed by a semi-additive method.

[0014] Using a roll-to-roll sputtering device and plating device, a copper layer 20 can be formed on the surface of a long strip of base film 10. This results in a long strip of copper-clad laminate 1. The long strip of copper-clad laminate 1 is cut longitudinally by a cutting device to a desired width. When the copper-clad laminate 1 is cut, the edges after cutting may become wavy (flare). In particular, if the copper-clad laminate is thin (for example, 10 to 15 μm thick) and easily stretches, flare is likely to occur when it is cut.

[0015] Next, the cutting device AA will be described. As shown in Figure 2, the cutting device AA has a supply device 31. A raw roll of copper-clad laminate is attached to the supply device 31. The raw roll is a wide copper-clad laminate (hereinafter referred to as raw roll 1W) before cutting that is wound into a roll. The supply device 31 pays out the raw roll 1W from the raw roll. The raw roll 1W is transported along a transport path determined by various rollers and supplied to the cutter unit 40.

[0016] The cutter unit 40 cuts the raw web 1W into three strips: the first cut product 1A, the hollowed-out portion 1M, and the second cut product 1B. Both edges of the raw web 1W may be cut. That is, the raw web 1W may be cut into five strips. The first cut product 1A, the hollowed-out portion 1M, and the second cut product 1B are all narrow copper-clad laminates after cutting. The hollowed-out portion 1M is the portion between the first cut product 1A and the second cut product 1B. The widths of the first cut product 1A and the second cut product 1B are not particularly limited, but are 240 to 260 mm. The width of the hollowed-out portion 1M is not particularly limited, but is 3 to 10 mm. For example, a 570 mm wide raw web 1W is cut to obtain a 250 mm wide first cut product 1A, a 5 mm wide hollowed-out portion 1M, and a 250 mm wide second cut product 1B.

[0017] Immediately after the cutter unit 40, there are arranged a first roller 32 around which the first cut workpiece 1A is wound, a hollowing roller 33 around which the hollowed portion 1M is wound, and a second roller 34 around which the second cut workpiece 1B is wound. These rollers 32, 33, 34 determine the angles at which the first cut workpiece 1A, the hollowed portion 1M, and the second cut workpiece 1B are pulled out from the cutter unit 40. Conversely, these pull-out angles can be adjusted by the arrangement of the rollers 32, 33, 34.

[0018] As shown in Fig. 3, in this specification, an extension line (usually a horizontal line) of the conveyance direction of the raw web 1W is set as a reference line, and the angle between the pull-out direction of the first cut product 1A pulled out from the cutter unit 40 and the reference line is set as a pull-out angle α of the first cut product 1A. Also, the pull-out direction of the first cut product 1A is set as a reference line, and the angle between the pull-out direction of the hollow portion 1M pulled out from the cutter unit 40 and the reference line is set as a pull-out angle β of the hollow portion 1M. Note that for both angles α and β, a positive value is used when the pull-out direction is downward from the reference line (clockwise in Fig. 3), and a negative value is used when the pull-out direction is upward from the reference line (counterclockwise in Fig. 3).

[0019] As shown in Fig. 2, the first cut product 1A is wound around a first roller 32, then transported along a transport path determined by various rollers, and supplied to a first winding section 35. The first winding section 35 winds the first cut product 1A into a roll. Similarly, the second cut product 1B is wound around a second roller 34, then transported along a transport path determined by various rollers, and supplied to a second winding section 36. The second winding section 36 winds the second cut product 1B into a roll.

[0020] A drive roller 37 and a driven roller 38 are disposed downstream of the hollowing roller 33. The hollowed portion 1M is sandwiched between the drive roller 37 and the driven roller 38 and is transported by the drive of the drive roller 37. The hollowed portion 1M is collected in a collection tank or the like.

[0021] The cutter unit 40 uses a gang cut method. As shown in FIG. 4, at least two upper blades 41, 41 are provided on an upper rotating shaft (not shown). At least two lower blades 42, 42 are provided on a lower rotating shaft (not shown). The two upper blades 41, 41 are arranged at a predetermined distance from each other. The two lower blades 42, 42 are arranged immediately outside the two upper blades 41, 41. The raw web 1W is cut at two positions where the upper blades 41 and the lower blades 42 come into contact. Specifically, the raw web 1W is cut into a central hollow portion 1M and a first cut product 1A and a second cut product 1B on the left and right.

[0022] The upper rotating shaft is provided with a first upper support ring 43A, a central upper support ring 43M, and a second upper support ring 43B. The central upper support ring 43M is disposed between the two upper blades 41, 41. The diameter of the central upper support ring 43M is approximately the same as that of the upper blade 41. The first upper support ring 43A and the second upper support ring 43B are disposed on the left and right of the two upper blades 41, 41. The first upper support ring 43A and the second upper support ring 43B have a smaller diameter than the upper blade 41.

[0023] The lower rotating shaft is provided with a first lower support ring 44A, a central lower support ring 44M, and a second lower support ring 44B. The central lower support ring 44M is disposed between the two lower blades 42, 42. The central lower support ring 44M has a smaller diameter than the lower blade 42. The first lower support ring 44A and the second lower support ring 44B are disposed on the left and right of the two lower blades 42, 42. The diameters of the first lower support ring 44A and the second lower support ring 44B are approximately the same as that of the upper blade 41.

[0024] The first cut product 1A is cut while being sandwiched between the first upper support ring 43A and the first lower support ring 44A. The hollowed portion 1M is cut while being sandwiched between the central upper support ring 43M and the central lower support ring 44M. The second cut product 1B is cut while being sandwiched between the second upper support ring 43B and the second lower support ring 44B.

[0025] Because the cutter unit 40 has such a configuration, the cutting conditions for both end surfaces after cutting are substantially the same, and therefore copper-clad laminates 1A and 1B with small flare can be obtained.

[0026] To obtain cut products 1A and 1B with small flare, it is preferable to set the pull-out angle β of the hollowed portion 1M to -20° to 0°. Also, the winding tension of the cut products 1A and 1B is preferably 30 to 60 N, more preferably 30 to 40 N. Furthermore, it is preferable to set the pull-out angle α of the cut products 1A and 1B to 0° to 6°, more preferably 0° to 4°.

[0027] By cutting the wide copper clad laminate 1W using the cutting device AA having the above configuration, narrow copper clad laminates 1A and 1B can be obtained. The obtained copper clad laminates 1A and 1B have reduced flaring. [Example]

[0028] (Common conditions) A 12.5 μm thick polyimide film was prepared as the base film. The base film was a long strip measuring 570 mm wide. Copper layers were formed on both sides of the base film to obtain a copper-clad laminate. The copper layer consisted of a thin copper layer and a copper plating film. The thin copper layer was formed using a magnetron sputtering device. The copper plating film was formed using a roll-to-roll plating device. The thin copper layer was 100 nm thick, and the copper plating film was 0.4 μm thick. Therefore, the thickness of the copper-clad laminate was 13.5 μm.

[0029] Using the cutting device shown in Figure 2, a 570 mm wide copper clad laminate was cut into a 250 mm wide first cut product, a 5 mm wide hollowed-out section, and a 250 mm wide second cut product. The raw sheet was conveyed at a speed of 10 m / min and fed with a tension of 100 N.

[0030] (Pull-out angle of hollowed section) The pull-out angle β of the hollowed-out portion was changed in the range of -20° to +20°. The winding tension of the first cut product and the second cut product was 30 N. The pull-out angle α of the first cut product was 2°.

[0031] The edge of the hollowed-out portion of the first cut product was visually observed to determine whether or not there was a flare. The results are shown in Table 1. In Table 1, ○ indicates no flare (corresponding to a flare height of less than 100 μm), and × indicates the presence of a flare (corresponding to a flare height of 100 μm or more). [Table 1]

[0032] It was found that flaring can be suppressed by setting the pull-out direction of the hollowed-out part to the same as or higher than the reference line (pull-out direction of the first cut product). It is thought that if the hollowed-out part is cut by pulling it down, it will get caught between the lower blades and promote flaring. This can be suppressed by cutting the hollowed-out part by pulling it up. It was confirmed that in order to suppress flaring, it is preferable to set the pull-out angle β of the hollowed-out part to -20° to 0°.

[0033] (Winding tension of the first cut product) The winding tension of the first cut product and the second cut product was changed in the range of 30 to 100 N. The pull-out angle β of the hollowed-out portion was set to -10°. The pull-out angle α of the first cut product was set to 2°.

[0034] The edge of the hollowed-out portion of the obtained first cut product was visually observed to determine whether or not there was a flare. The results are shown in Table 2. In Table 2, ○ means no flare (corresponding to a flare height of less than 100 μm), △ means flare within the allowable range (corresponding to a flare height of 100 μm or more but less than 300 μm), and × means flare exceeding the allowable range (corresponding to a flare height of 300 μm or more). [Table 2]

[0035] There is a tendency that the lower the winding tension of the first cut product, the more effectively flaring can be suppressed. It is presumed that lowering the winding tension reduces the stress generated at the end of the cut product, thereby suppressing flaring. It has been confirmed that a winding tension of 30 to 60 N is preferable, and a tension of 30 to 40 N is more preferable, in order to suppress flaring.

[0036] (Pull-out angle of first cut product) The unwinding angle α of the first cut product was changed in the range of 0° to +10°. The winding tension of the first cut product and the second cut product was 30 N. The unwinding angle β of the hollowed portion was set to -10°.

[0037] A test piece measuring 300 mm in length and 156 mm in width was obtained from the resulting first cut product. The flare height of the edge of the hollowed-out portion of the first cut product was then determined using the following procedure. The test piece was placed on a flat plate, and the edge height of the test piece was measured using an optical microscope with a length measurement function in the Z-axis direction. The measurement range was 200 mm from the middle of the edge (300 mm in length) of the test piece, and the edge height was measured at 40 points at 5 mm intervals relative to the surface of the flat plate. The maximum value of the 40 measurement results is shown in Table 3. A flare height of less than 100 μm was evaluated as "○" (no flare), a flare height of 100 μm to less than 300 μm was evaluated as "△" (flare within the acceptable range), and a flare height of 300 μm or more was evaluated as "×" (flare exceeding the acceptable range).

[0038] [Table 3]

[0039] There is a tendency that the shallower the pull-out angle α of the first cut product, the more the flare can be suppressed. It has been confirmed that in order to suppress flare, the pull-out angle α is preferably set to 0° to 6°, and more preferably to 0° to 4°. [Explanation of symbols]

[0040] AA cutting device 1W raw fabric 1A 1st cutting product 1M hollow part 1B 2nd cutting product 31 Feeding device 32 First Roller 33 Hollowing roller 34 Second Roller 35 First winding section 36 Second winding section 40 Cutter unit 41 Upper blade 42 Lower blade

Claims

1. A method for cutting a raw sheet of copper clad laminate into a first cut product, a hollowed-out portion, and a second cut product using a gang cutter unit, an extension line of the conveying direction of the raw web is defined as a first reference line, an angle formed between the pulling-out direction of the first cut product and the first reference line is defined as a pulling-out angle α of the first cut product, and the pulling-out angle α is defined as positive when the pulling-out direction of the first cut product is lower than the first reference line and negative when the pulling-out direction is higher than the first reference line, and the pulling-out angle α is 0° to 6°, a pull-out direction of the first cut product is defined as a second reference line, an angle formed between the pull-out direction of the hollow portion and the second reference line is defined as a pull-out angle β of the hollow portion, and the pull-out angle β is defined as positive when the pull-out direction of the hollow portion is lower than the second reference line and negative when the pull-out angle is higher than the second reference line, and the pull-out angle β is −20° to 0°, The winding tension of the first cut product is 30 to 60 N. A method for producing a copper-clad laminate, comprising:

2. The first cut product has a thickness of 10 to 15 μm and a width of 240 to 260 mm.

2. The method for producing a copper clad laminate according to claim 1.

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