JP2014095679A - Copper foil surface state evaluation device, copper foil surface state evaluation program, computer readable recording medium having the same recorded and copper foil surface state evaluation method - Google Patents

Abstract

The surface state of a copper foil is efficiently and accurately evaluated.
After the surface-treated surface side of the surface-treated copper foil is bonded to at least one surface of the transparent substrate, the surface-treated copper foil is removed by etching, and a mark present under the transparent substrate is An imaging means for taking an image through a transparent substrate, and an observation point-lightness graph making means for preparing an observation point-lightness graph by measuring the brightness at each observation point along a direction perpendicular to the direction in which the observed mark extends. And a copper foil surface state evaluation means for evaluating the visibility of the transparent substrate using a brightness curve generated from an end portion of the mark to a portion without the mark, and evaluating a surface state of the copper foil. It is an evaluation apparatus for the surface state of the foil, and the copper surface state evaluation means is a difference ΔB (ΔB = Bt−) between the top average value Bt and the bottom average value Bb of the brightness curve generated from the end of the mark to the portion where there is no mark. B The evaluation apparatus which evaluates the visibility of the said transparent base material using b), and evaluates the surface state of copper foil.
[Selection] Figure 1

Description

  The present invention relates to a copper foil surface state evaluation apparatus, a copper foil surface state evaluation program, a computer-readable recording medium on which the program is recorded, and a copper foil surface state evaluation method.

  In a small electronic device such as a smartphone or a tablet PC, a flexible printed wiring board (hereinafter referred to as FPC) is adopted because of easy wiring and light weight. In recent years, with the enhancement of functions of these electronic devices, the signal transmission speed has been increased, and impedance matching has become an important factor in FPC. As a measure for impedance matching with respect to an increase in signal capacity, a resin insulation layer (for example, polyimide) serving as a base of an FPC has been increased in thickness. On the other hand, processing such as bonding to a liquid crystal substrate and mounting of an IC chip is performed on the FPC, but the alignment at this time is the resin insulation remaining after etching the copper foil in the laminate of the copper foil and the resin insulating layer Since it is performed through a positioning pattern that is visible through the layer, the visibility of the resin insulating layer and the surface state of the copper foil laminated on the resin insulating layer that affects the resin insulating layer are important.

  As a method for evaluating the visibility of such a resin insulating layer, in Patent Document 1, an image taken through a resin insulating layer with a CCD camera is observed and evaluated. In Patent Document 2, it is evaluated whether or not a test pattern is distorted in an image taken by a CCD camera from an angle of 30 ° with respect to the horizontal plane of the resin insulating layer to be evaluated.

JP 2003-309336 A JP 2006-001056 A

However, in the case of simply observing an image by observing with a CCD camera as in Patent Document 1, there is a limit to the accuracy of the visibility evaluation. In reality, it is impossible to determine whether or not the provided mark can be visually recognized through the transparent base material, which is problematic in terms of manufacturing cost. The same applies to a method of evaluating whether or not a test pattern is distorted in the image as in Patent Document 2. And if the precision of visibility evaluation is low in this way, the precision of the evaluation of the surface state of the copper foil laminated | stacked on a resin insulating layer will also become low.
The present invention relates to a copper foil surface state evaluation apparatus capable of efficiently and accurately evaluating the surface state of a copper foil, a copper foil surface state evaluation program, a computer-readable recording medium on which the program is recorded, and A method for evaluating the surface state of a copper foil is provided.

  As a result of intensive studies, the present inventors have bonded the surface-treated surface side of the surface-treated copper foil to at least one surface of the transparent substrate, and then removed the surface-treated copper foil by etching. The mark existing under the transparent base material after removing the copper foil by etching is photographed through the transparent base material, and the brightness near the mark end portion drawn in the observation point-lightness graph obtained from the image of the mark part. Focusing on the magnitude of the change in the curve and evaluating the magnitude of the change in the brightness curve, the visibility of the transparent substrate can be improved without being affected by the type of transparent substrate and the thickness of the transparent substrate. It was found that the surface state of the copper foil laminated on the transparent substrate can be efficiently and accurately evaluated.

  The present invention completed on the basis of the above knowledge, in one aspect, after the surface-treated surface side of the surface-treated copper foil is bonded to at least one surface of the transparent substrate, the surface-treated copper foil is removed by etching. And the imaging means for photographing the mark existing under the transparent base material after the surface-treated copper foil is removed by etching through the transparent base material, and the image obtained by the photographing were observed An observation point-lightness graph preparation means for measuring the lightness of each observation point along a direction perpendicular to the direction in which the mark extends to create an observation point-lightness graph, and an end of the mark in the observation point-lightness graph To evaluate the visibility of the transparent substrate using a brightness curve generated over the portion without the mark, and evaluate the surface state of the copper foil based on the visibility evaluation result A copper foil surface state evaluation device comprising a foil surface state evaluation means, wherein the copper foil surface state evaluation means includes a top average value Bt of a brightness curve generated from an end portion of the mark to a portion without the mark, and An evaluation device for the surface state of a copper foil that evaluates visibility using a difference ΔB (ΔB = Bt−Bb) from the bottom average value Bb and evaluates the surface state of the copper foil based on the evaluation result of the visibility It is.

In one embodiment of the copper foil surface state evaluation apparatus according to the present invention, the copper foil surface state evaluation means includes a top average value Bt and a bottom average value of a brightness curve generated from an end portion of the mark to a portion without the mark. A value ΔB (ΔB = Bt−Bb) with respect to Bb and a value indicating a position of an intersection closest to the mark among intersections of the brightness curve and Bt in the observation point-brightness graph, In the depth range from the intersection with Bt to 0.1 ΔB with reference to Bt, when the value indicating the position of the intersection closest to the mark among the intersections of the lightness curve and 0.1 ΔB is t2, the following Sv defined by equation (1);
Sv = (ΔB × 0.1) / (t1-t2) (1)
Is used to evaluate the visibility, and the surface state of the copper foil is evaluated based on the visibility evaluation result.

  In another embodiment, the copper foil surface state evaluation apparatus according to the present invention further includes smoothing processing means for reducing variations in brightness of an image obtained by photographing by the photographing means, and the observation point-lightness graph is provided. A production means creates an observation point-lightness graph using the lightness after the smoothing process.

  In still another embodiment of the copper foil surface state evaluation apparatus according to the present invention, a line-shaped mark printed on a printed material laid under the transparent substrate is a mark present under the transparent substrate. The observation point-lightness graph preparation means measures and observes the lightness at each observation point along the direction perpendicular to the direction in which the observed line-shaped mark extends with respect to the image obtained by the photographing. Create a spot-lightness graph.

  In yet another embodiment of the copper foil surface state evaluation apparatus according to the present invention, in the visibility evaluation by the copper foil surface state evaluation means, the case where ΔB (ΔB = Bt−Bb) is 40 or more is good. Is determined.

  In another embodiment, the copper foil surface state evaluation apparatus according to the present invention is preferable in the case where ΔB (ΔB = Bt−Bb) is 50 or more in the visibility evaluation by the copper foil surface state evaluation means. Is determined.

  In yet another embodiment, the copper foil surface state evaluation apparatus according to the present invention determines that the Sv is 3.5 or higher in the visibility evaluation by the copper foil surface state evaluation means.

  In yet another embodiment, the copper foil surface state evaluation apparatus according to the present invention determines that the case where the Sv is 3.9 or more is good.

  In yet another embodiment, the copper foil surface state evaluation apparatus according to the present invention determines that the Sv is 5.0 or more as good.

  In another aspect, the present invention is a program for causing a computer to function as the copper foil surface state evaluation apparatus of the present invention.

  In still another aspect of the present invention, there is provided a computer-readable recording medium in which the evaluation program for the surface condition of the copper foil of the present invention is recorded.

  In yet another aspect of the present invention, after the surface-treated surface side of the surface-treated copper foil is bonded to at least one surface of the transparent substrate, the surface-treated copper foil is removed by etching. The mark existing under the transparent base material after removing the foil by etching is photographed through the transparent base material, and the image obtained by the photographing is in a direction perpendicular to the direction in which the observed mark extends. A lightness at each observation point is measured to produce an observation point-lightness graph. In the observation point-lightness graph, the transparent substrate is formed using a lightness curve generated from an end of the mark to a portion without the mark. Is a copper foil surface state evaluation method for evaluating the surface state of the copper foil based on the visibility evaluation result. The visibility of the transparent substrate is evaluated using the difference ΔB (ΔB = Bt−Bb) between the top average value Bt and the bottom average value Bb of the brightness curve generated from the part to the part where the mark is not present, It is the evaluation method of the surface state of copper foil which evaluates the surface state of copper foil based on the evaluation result of the visibility of material.

  According to the present invention, the surface state of the copper foil is efficiently and accurately evaluated.

It is a schematic diagram of the evaluation apparatus of the surface state of the copper foil which concerns on embodiment of this invention. It is a flowchart of the evaluation method of the surface state of the copper foil which concerns on embodiment of this invention. It is a schematic diagram which defines Bt and Bb in case a mark width is about 1.3 mm. It is a schematic diagram which defines Bt and Bb in case a mark width is about 0.3 mm. It is a schematic diagram which defines t1, t2, and Sv. It is a schematic diagram showing the structure of the imaging | photography means and the measuring method of a lightness curve in the case of evaluation of the lightness curve in case the width | variety of a mark is 0.1-0.4 mm. It is a schematic diagram showing the structure of the imaging | photography means and the measuring method of a brightness curve in the case of evaluation of the brightness curve in case the width | variety of a mark is 1.0-2.0 mm.

(Copper foil surface state evaluation device, copper foil surface state evaluation method, copper foil surface state evaluation program, and recording medium)
FIG. 1 is a schematic diagram of a copper foil surface state evaluation apparatus 10 according to an embodiment of the present invention. The copper foil surface state evaluation apparatus 10 according to the embodiment of the present invention includes a photographing unit 11 that photographs the mark 16 existing under the transparent base material 17 provided on the stage 15 through the transparent base material 17. , A computer 12 that performs various processes based on image signals from the imaging means 11, a display means 13 that displays predetermined images and the like based on various signals from the computer 12, a transparent substrate 17 on the stage, and a mark 16 is provided with illumination means 14 for irradiating light. The transparent substrate 17 is not particularly limited, and may be a resin substrate such as glass or polyimide as long as it is transparent. In the present invention, the term “transparent” includes light transparency. The mark in the present invention may be a mark printed on a printed matter such as paper, or may be a copper wiring, and may take any form as long as it is a mark serving as a mark. The mark may be a printed material, a metal, an inorganic material, an organic material, or any mark. If the mark is in the form of a line, it is easy to create an observation point-lightness graph by measuring the lightness of each observation point along the direction crossing the observed mark for an image obtained by photographing. .

  The flexible printed wiring board (FPC) is subjected to processing such as bonding to a liquid crystal substrate and mounting of an IC chip. The alignment at this time is the resin insulation layer that remains after etching the copper foil of the copper-clad laminate. The visibility of the resin insulating layer is important because it is performed through a positioning pattern that is visible through the screen. And evaluation of the surface state of the copper foil which affects the visibility of such a resin insulation layer is needed. In the present invention, for the efficient and accurate visibility evaluation of such a resin insulating layer and the evaluation of the surface state of the copper foil, in the present invention, at least one surface is subjected to a surface treatment such as a roughening treatment. After the surface-treated metal foil is bonded to at least one surface of the transparent substrate from the surface side subjected to the surface treatment such as the roughening treatment, the metal foil is removed by etching. Although the said metal foil is not specifically limited, Copper foil, aluminum foil, nickel foil, copper alloy foil, nickel alloy foil, aluminum alloy foil, stainless steel foil, iron foil, iron alloy foil, etc. can be used.

  The imaging means 11 includes an imaging device, an image processing unit configured with an image processing circuit to which an output of the imaging device is input, a control unit configured with a control circuit that controls the image processing unit, a lens, and the like. Equipped with an optical system. As the photographing means 11, for example, a CCD camera or the like can be used. The photographing means 11 photographs the mark 16 existing under the transparent base material 17 provided on the stage 15 through the transparent base material 17 and acquires an image.

  The computer 12 performs various processes based on the image signal from the imaging unit 11. The computer 12 measures the lightness of each observation point along the direction perpendicular to the direction in which the observed mark 16 extends with respect to the image signal from the image pickup means 11, and creates an observation point-lightness graph. In the production means and the observation point-brightness graph, the visibility of the transparent substrate 17 is evaluated using a brightness curve generated from the end portion of the mark 16 to the portion where the mark 16 is not present, and copper is evaluated based on the visibility evaluation result. And a copper foil surface state evaluating means for evaluating the surface state of the foil.

  The computer 12 further includes smoothing processing means for reducing variations in lightness of the image obtained by photographing by the photographing means 11, and the observation point-lightness graph creating means uses the lightness after the smoothing processing to observe point-lightness. A graph may be created.

  Further, the mark 16 present under the transparent base material 17 is a line-shaped mark 16 printed on a printed material laid under the transparent base material 17, and the observation point-lightness graph preparation means is obtained by photographing. For the obtained image, the brightness at each observation point may be measured along the direction perpendicular to the direction in which the observed line-shaped mark 16 extends to create an observation point-lightness graph.

  The computer 12 includes a memory as storage means. In this memory, the digitized image from the imaging means 11, observation point-brightness graph preparation formula, visibility evaluation formula, copper foil surface condition evaluation formula, evaluation value at each stage, etc. are recorded in a computer-readable manner. (So-called preservation).

  Based on various signals from the computer 12, the display unit 13 displays a predetermined image, a numerical value, and the like such as an observation point-lightness graph, a visibility evaluation result, and a copper foil surface state evaluation result.

Next, the copper foil surface state evaluation method using the copper foil surface state evaluation apparatus 10 according to the above embodiment will be described with reference to the flowchart shown in FIG. The flow chart shown in FIG. 2 is an embodiment of the copper foil surface state evaluation method using the copper foil surface state evaluation apparatus 10 according to the present invention, and the copper foil surface state evaluation apparatus of the present invention. The evaluation method that can be realized in 10 is not limited to that shown in the flowchart of FIG. In particular, the visibility may not be evaluated by both measured values of ΔB and Sv, and the visibility may be evaluated only by ΔB. Further, although the smoothing process is performed on the image obtained by photographing in FIG. 2 before creating the observation point-lightness graph, the present invention is not limited to this, for example, after creating the observation point-lightness graph. You may go.
In the copper foil surface state evaluation method using the copper foil surface state evaluation apparatus 10, first, a surface-treated metal foil having at least one surface subjected to a surface treatment such as a roughening treatment is treated with a roughening treatment or the like. A transparent base material 17 prepared by removing the metal foil by etching after being bonded to at least one surface of the transparent base material from the surface-treated surface side is prepared. Next, the mark 16 existing under the transparent base material 17 is photographed by the photographing means 11 through the transparent base material 17. The signal of the image photographed by the photographing means 11 is sent to the computer 12. The observation point-lightness graph creating means of the computer 12 measures the lightness of each observation point along the direction perpendicular to the direction in which the observed mark 16 extends with respect to the image signal from the image pickup means 11, and the observation point-lightness graph. Is made. The surface condition evaluation means for the copper foil of the computer 12 evaluates the visibility of the transparent substrate 17 by the brightness curve generated from the end of the mark 16 to the portion without the mark 16 in the observation point-lightness graph. Based on the evaluation result, the surface state of the surface-treated metal foil that has been bonded to the transparent substrate 17 is evaluated. Conventionally, unless actually produced on the production line, it was impossible to determine whether or not the marks provided for alignment etc. could be seen through the transparent base material, and there was a problem in terms of production cost . However, if the copper foil surface state evaluation apparatus 10 according to the present invention is used, the above-described configuration easily and efficiently evaluates the visibility of the transparent substrate 17 even in the laboratory alone, thereby efficiently and accurately. It becomes possible to evaluate the surface state of the copper foil. For example, when the evaluation result of the visibility of the transparent substrate 17 is good, it can be evaluated that the surface state of the copper foil is good as it is.

  The copper foil surface state evaluation means of the computer 12 uses the difference ΔB (ΔB = Bt−Bb) between the top average value Bt and the bottom average value Bb of the brightness curve generated from the end of the mark 16 to the portion where the mark 16 is not present. The visibility is evaluated, and the surface state of the copper foil is evaluated using the evaluation result.

Moreover, the surface condition evaluation means of the copper foil of the computer 12 is the difference ΔB (ΔB = Bt−Bb) between the top average value Bt and the bottom average value Bb of the brightness curve generated from the end of the mark 16 to the portion where the mark 16 is not present. In the observation point-lightness graph, the value indicating the position of the intersection closest to the mark 16 among the intersections of the lightness curve and Bt (the value on the horizontal axis of the observation point-lightness graph) is t1, and the lightness curve In the depth range from the intersection with Bt to 0.1 ΔB with reference to Bt, a value indicating the position of the intersection closest to the mark among the intersections of the lightness curve and 0.1 ΔB (the side of the observation point-lightness graph) When the value of the axis is t2, Sv defined by the following equation (1):
Sv = (ΔB × 0.1) / (t1-t2) (1)
Visibility may be evaluated using, and the surface state of the copper foil may be evaluated using this evaluation result.
In the observation position-lightness graph described above, the horizontal axis indicates position information (pixel × 0.1), and the vertical axis indicates the value of brightness (gradation).
According to such a configuration, it is possible to easily and efficiently evaluate the visibility of the transparent base material 17 easily and efficiently even in the laboratory alone, and using this evaluation result, the copper foil can be easily and efficiently used only in the laboratory. The surface state of the film can be evaluated.

The computer 12 further includes smoothing processing means for reducing variations in lightness of the image obtained by photographing by the photographing means 11, and the observation point-lightness graph creating means uses the lightness after the smoothing processing to observe point-lightness. It is preferable to create a graph. Since smoothing processing by the smoothing processing means is performed on the data (original waveform) including lightness noise obtained from the image obtained by the photographing by the photographing means 11, the variation in the lightness is reduced. The visibility of the material 17 can be more accurately evaluated. The smoothing processing by the smoothing processing means can be performed by various smoothing programs. For example, smoothing processing by a second-third order polynomial fitting method, smoothing processing by Fourier transform, or smoothing processing by a moving average method is used. be able to. The smoothing process may be performed using various known smoothing programs. Further, the smoothing process of the brightness data may be performed for both the portion with the mark 16 and the portion without the mark 16, may be performed for the portion with the mark 16, may be performed on the portion without the mark 16, or may be performed partially. May be.
Note that an image obtained by photographing by the photographing unit 11 may be prepared in advance for an observation point-lightness graph of data (original waveform) including the lightness noise before performing the lightness smoothing process.

Moreover, in the visibility evaluation by the surface state evaluation means of the copper foil, when evaluating the visibility based only on the above ΔB value, the top average value of the brightness curve generated from the end of the mark 16 to the portion without the mark 16 When the difference ΔB between Bt and the bottom average value Bb is 40 or more, the visibility and the surface state of the copper foil may be determined to be good.
Furthermore, when the visibility is evaluated based on the ΔB value and the Sv value in the visibility evaluation by the surface state evaluation means of the copper foil, the top of the brightness curve generated from the end portion of the mark 16 to the portion where the mark 16 is not present. The difference ΔB between the average value Bt and the bottom average value Bb is 40 or more. In the observation point-lightness graph, a value indicating the position of the intersection closest to the mark among the intersections of the lightness curve and Bt (the observation point− In the depth range from the intersection of the lightness curve and Bt to 0.1 ΔB with reference to Bt, the value of the horizontal axis of the lightness graph is t1, and the mark 16 is the most in the intersection of the lightness curve and 0.1ΔB. When the value indicating the position of the closest intersection (the value of the horizontal axis of the observation point-lightness graph) is t2, it is determined that the visibility and the surface state of the copper foil are good when Sv is 3.5 or more. May be.
When Sv is 3.9 or more, preferably 4.5 or more, preferably 5.0 or more, more preferably 5.5 or more, it is more preferable to determine that the visibility and the surface state of the copper foil are good. . The upper limit of Sv is not particularly limited, but is, for example, 70 or less, 30 or less, 15 or less, or 10 or less.
When ΔB (ΔB = Bt−Bb) is 50 or more, it is preferable to determine that the visibility and the surface state of the copper foil are good, and when it is 60 or more, the visibility and the surface state of the copper foil are good. It is more preferable to judge. The upper limit of ΔB is not particularly limited, but is, for example, 100 or less, 80 or less, or 70 or less. According to such an evaluation, the visibility of the transparent base material 17 can be efficiently and accurately evaluated, and the evaluation of the surface state of the copper foil can be performed efficiently and accurately using this evaluation result. be able to.

Here, “top average value Bt of the lightness curve”, “bottom average value Bb of the lightness curve”, and “t1”, “t2”, and “Sv” described later will be described with reference to the drawings. For the “bottom average value Bb of the lightness curve”, the width of the mark is increased (for example, the width of the mark is 0.7 mm or more, for example, 0.8 mm or more, for example, 5 mm or less, 4 mm or less, for example, about 1.3 mm). And the mark width is reduced (for example, the mark width is 0.01 mm or more, 0.05 mm or more, 0.1 mm or more, 0.8 mm or less, 0.7 mm or less, 0.00 mm or less). Since the definition is different from that of 6 mm or less, for example, 0.3 mm, each case will be described.
FIG. 3 is a schematic diagram for defining Bt and Bb when the mark width is increased (about 1.3 mm). The “mark” in FIG. 3 indicates a line-like mark (width of about 1.3 mm) of the printed matter observed in the image obtained by photographing with the CCD camera. A curve drawn so as to overlap the mark indicates a brightness curve generated from the end of the mark to a portion without the mark in the observation point-lightness graph. As shown in FIG. 3, the “top average value Bt of the brightness curve” is the average of the brightness when measured at 5 locations (total 10 locations on both sides) at 30 μm intervals from the positions 100 μm away from the end positions on both sides of the mark. Indicates the value. The “bottom average value Bb of the lightness curve” indicates an average value of lightness when 11 positions are measured at intervals of 100 μm from a position inside 100 μm from the end position of the mark. Note that the interval between observation points for measuring the average value of the brightness can be appropriately selected in the range of 1 μm to 500 μm depending on the shape of the brightness curve. In order to avoid the bias of the observation points, it is preferable that the intervals between the observation points are substantially equal or equal. Note that the intervals between the observation points do not have to be substantially equal and may not be equal. Further, it is considered that the wider the measurement interval, the more the influence of a specific observation point can be eliminated and the error due to the observation point can be reduced.
FIGS. 4A and 4B are schematic diagrams for defining Bt and Bb when the mark width is about 0.3 mm. When the width of the mark is about 0.3 mm, the bottom is the same as in the case of a V-shaped brightness curve as shown in FIG. 4A and the case of about 1.3 mm as shown in FIG. May result in a lightness curve having In any case, the “top average value Bt of the lightness curve” is 5 locations at intervals of 30 μm from the positions 50 μm away from the end positions on both sides of the mark, as in the case where the mark width is about 1.3 mm ( The average value of the brightness when measured at 10 locations on both sides). On the other hand, the “bottom average value Bb of the lightness curve” indicates the minimum value of lightness at the tip of the V-shaped valley when the lightness curve is V-shaped as shown in FIG. When it has the bottom of (b), the value of the center part of about 0.3 mm is shown. Note that the interval between observation points for measuring the average value of the brightness can be appropriately selected in the range of 1 μm to 500 μm depending on the shape of the brightness curve. In order to avoid the bias of the observation points, it is preferable that the intervals between the observation points are substantially equal or equal. Note that the intervals between the observation points may not be substantially equal, and may not be equal. Further, it is considered that the wider the measurement interval, the more the influence of a specific observation point can be eliminated and the error due to the observation point can be reduced.
FIG. 5 is a schematic diagram for defining t1, t2, and Sv. “T1 (pixel × 0.1)” is a value indicating an intersection point closest to the line-shaped mark among intersection points of the lightness curve and Bt and a position of the intersection point (value on the horizontal axis of the observation point-lightness graph) ). “T2 (pixel × 0.1)” is the line-shaped mark among the intersections of the lightness curve and 0.1ΔB in the depth range from the intersection of the lightness curve and Bt to 0.1ΔB with reference to Bt. And the value (the value on the horizontal axis of the observation point-brightness graph) indicating the position of the intersection closest to. At this time, regarding the slope of the brightness curve indicated by the line connecting t1 and t2, Sv (gradation / pixel × 0.1) calculated by 0.1 ΔB in the y-axis direction and (t1−t2) in the x-axis direction. ). One pixel on the horizontal axis corresponds to a length of 10 μm. Further, Sv is measured on both sides of the mark, and a small value is adopted. Further, when the shape of the lightness curve is unstable and there are a plurality of the “intersections between the lightness curve and Bt”, the intersection closest to the mark is adopted.
In the image taken by the photographing means 11, the lightness is high in a portion where no mark is attached, but the lightness is lowered as soon as the mark end is reached. If the visibility of the transparent substrate 17 is good, such a lowered state of brightness is clearly observed. On the other hand, if the visibility of the transparent substrate 17 is poor, the lightness does not suddenly drop from “high” to “low” in the vicinity of the end of the mark, but the state of decline is moderate and the state of lightness decline is reduced. It will be unclear.
Based on such knowledge, the present invention places an observation mark obtained from the image of the mark portion taken by the photographing means 11 through the transparent base material 17, for example, with a printed matter with a mark placed under the transparent base material 17. -The brightness curve near the edge of the mark drawn in the brightness graph is controlled. More specifically, the difference ΔB (ΔB = Bt−Bb) between the top average value Bt and the bottom average value Bb of the lightness curve is set to 40 or more, and in the observation point-lightness graph, among the intersections of the lightness curve and Bt, Depth range from the intersection of the lightness curve and Bt to 0.1 ΔB on the basis of Bt, where t1 is the value indicating the position of the intersection closest to the line mark (value on the horizontal axis of the observation point-lightness graph) , When the value indicating the position of the intersection closest to the mark among the intersections of the lightness curve and 0.1 ΔB (the value of the observation point—the horizontal axis of the lightness graph) is t2, By evaluating the defined Sv, it is possible to accurately evaluate the visibility of the transparent substrate, and it is possible to efficiently and more accurately evaluate the surface state of the copper foil using this evaluation result. It is preferable to determine that the visibility and the surface state of the copper foil are good when Sv is 3.5 or more. When Sv is 3.9 or more, preferably 4.5 or more, preferably 5.0 or more, more preferably 5.5 or more, it is more preferable to determine that the visibility and the surface state of the copper foil are good. . Further, when ΔB is preferably 50 or more, it is more preferable to determine that the visibility and the surface state of the copper foil are good, and preferably, when ΔB is 60 or more, the visibility and the surface state of the copper foil are determined to be good. Good. The upper limit of ΔB is not particularly limited, but is, for example, 100 or less, 80 or less, or 70 or less. The upper limit of Sv is not particularly limited, but is, for example, 70 or less, 30 or less, 15 or less, or 10 or less. According to such a configuration, the boundary between the mark and the non-mark portion becomes clearer, the positioning accuracy is improved, the error due to the mark image recognition is reduced, and the alignment can be performed more accurately. Therefore, when the values of Sv and ΔB are within the range of the values of Sv and ΔB described above, it may be determined that the surface state of the copper foil is good.

  In addition, by causing the computer to execute the processing procedure as described above, the visibility of the transparent substrate can be efficiently and accurately evaluated, and the surface of the copper foil can be efficiently and accurately evaluated using the evaluation result. A state assessment can be performed.

  Furthermore, by using this program recorded on a recording medium such as an optical or magnetic disk so that it can be read by a computer, this program can be realized on other computers, and the same effects as the above-described processing procedure can be obtained. .

As Examples A1 to 30 and Examples B1 to 14, various copper foils were prepared, and plating treatment was performed on one surface under the conditions described in Table 1 as a roughening treatment.
After performing the above-mentioned roughening plating process, the plating process for the following heat-resistant layer and rust prevention layer formation was performed about Example A1-10, 12-27, Example B3, 4, 6, 9-15. .
The conditions for forming the heat-resistant layer 1 are shown below.
Liquid composition: Nickel 5-20 g / L, cobalt 1-8 g / L
pH: 2-3
Liquid temperature: 40-60 degreeC
Current density: 5 to 20 A / dm ²
Coulomb amount: 10-20 As / dm ²
A heat-resistant layer 2 was formed on the copper foil provided with the heat-resistant layer 1. For Examples B5, 7, and 8, the rough plating treatment was not performed, and the heat-resistant layer 2 was directly formed on the prepared copper foil. The conditions for forming the heat-resistant layer 2 are shown below.
Liquid composition: nickel 2-30 g / L, zinc 2-30 g / L
pH: 3-4
Liquid temperature: 30-50 degreeC
Current density: 1 to ^{2 A} / dm ²
Coulomb amount: 1-2 As / dm ²
On the copper foil which gave the said heat-resistant layers 1 and 2, the antirust layer was further formed. The conditions for forming the rust preventive layer are shown below.
Liquid composition: potassium dichromate 1-10 g / L, zinc 0-5 g / L
pH: 3-4
Liquid temperature: 50-60 degreeC
Current density: 0 to ^{2 A} / dm ² (for immersion chromate treatment)
Coulomb amount: 0 to ^{2 As} / dm ² (for immersion chromate treatment)
On the copper foil which gave the said heat-resistant layers 1 and 2 and a rust prevention layer, the weathering layer was further formed. The formation conditions are shown below.
As a silane coupling agent having an amino group, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane (Example A17, 24-27), N-2- (aminoethyl) -3-aminopropyltri Ethoxysilane (Examples A1 to 16), N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane (Examples A18, 28, 29), 3-aminopropyltrimethoxysilane (Example A19), 3 -Aminopropyltriethoxysilane (Examples A20, 21), 3-triethoxysilyl-N- (1,3-dimethyl-butylidene) propylamine (Example A22), N-phenyl-3-aminopropyltrimethoxysilane In (Example A23), coating and drying were performed to form a weather-resistant layer. These silane coupling agents can be used in combination of two or more. Similarly, in Examples B1 to 15, coating and drying were performed with N-2- (aminoethyl) -3-aminopropyltrimethoxysilane to form a weather resistant layer.

In addition, the rolled copper foil was manufactured as follows. After manufacturing the copper ingot of the composition shown in Table 2 and performing hot rolling, annealing and cold rolling of a continuous annealing line at 300 to 800 ° C. were repeated to obtain a rolled sheet having a thickness of 1 to 2 mm. This rolled sheet was annealed in a continuous annealing line at 300 to 800 ° C. and recrystallized, and finally cold-rolled to the thickness shown in Table 2 to obtain a copper foil. “Tough pitch copper” in the “Type” column of Table 2 indicates tough pitch copper standardized in JIS H3100 C1100, and “Oxygen-free copper” indicates oxygen-free copper standardized in JIS H3100 C1020. “Tough pitch copper + Ag: 100 ppm” means that 100 mass ppm of Ag is added to tough pitch copper.
The electrolytic copper foil used was an electrolytic copper foil HLP foil manufactured by JX Nippon Mining & Metals. When electrolytic polishing or chemical polishing was performed, the plate thickness after electrolytic polishing or chemical polishing was described.
Table 2 lists the points of the copper foil preparation process before the surface treatment. “High gloss rolling” means that the final cold rolling (cold rolling after the final recrystallization annealing) was performed at the value of the oil film equivalent. “Normal rolling” means that the final cold rolling (cold rolling after the final recrystallization annealing) was performed at the oil film equivalent value described. “Chemical polishing” and “electropolishing” mean the following conditions.
“Chemical polishing” was performed using an etching solution of 1 to 3% by mass of H ₂ SO ₄ , 0.05 to 0.15% by mass of H ₂ O ₂ , and the remaining water, and the polishing time was 1 hour.
“Electropolishing” is a condition of phosphoric acid 67% + sulfuric acid 10% + water 23%, voltage 10 V / cm ² , and the time shown in Table 2 (when electropolishing for 10 seconds, the polishing amount is 1 to 2 μm. ).

About each sample of the Example produced as mentioned above, various evaluation was performed as follows using the evaluation apparatus of the surface state of the copper foil of the structure similar to what was shown in FIG.
(1) Lightness curve A copper foil was bonded to both sides of a polyimide film (Kaneka thickness 25 μm, 50 μm, Toray DuPont thickness 50 μm), and the copper foil was removed by etching (ferric chloride aqueous solution) to prepare a sample film. . Subsequently, a printed material on which a line-shaped black mark was printed was laid under the sample film, and the printed material was photographed with a CCD camera through the sample film. The width of the mark used here was 0.1 to 0.4 mm. Next, in the observation point-brightness graph prepared by measuring the lightness of each observation point along the direction perpendicular to the direction in which the observed line-shaped mark extends, for an image obtained by photographing with a computer, The brightness curve generated from the end of the mark to the portion without the mark, and ΔB and t1, t2, and Sv were measured. FIG. 6 is a schematic diagram showing the configuration of the photographing means used at this time and the measurement method of the brightness curve.
ΔB, t1, t2, and Sv were measured by the following photographing means as shown in FIG. One pixel on the horizontal axis corresponds to a length of 10 μm.
The photographing means includes a CCD camera, a stage (white) on which a polyimide substrate is placed with a marked paper underneath, an illumination power source for irradiating light onto the photographing portion of the polyimide substrate, and a paper with a mark to be photographed. A transporter (not shown) for transporting the evaluation polyimide substrate placed below onto the stage is provided. The main specifications of the photographing means are as follows:
・ Photographing means: Nireco Corporation sheet inspection device Mujken
CCD camera: 8192 pixels (160 MHz), 1024 gradation digital (10 bits)
・ Power supply for lighting: High frequency lighting power supply (power supply unit x 2)
・ Lighting: Fluorescent lamp (30W)
For the lightness shown in FIG. 6, 0 means “black”, lightness 255 means “white”, and the gray level from “black” to “white” (black and white shading, gray scale) Is divided into 256 gradations for display.
In addition, since the used mark width was as small as 0.1 to 0.4 mm, the produced brightness curve has a V shape as shown in FIG. 4A or a bottom as shown in FIG. It became V type which has.

(2) Evaluation of visibility (resin transparency) and surface condition of copper foil;
The copper foil was bonded to both surfaces of a polyimide film (Kaneka thickness 25 μm, 50 μm, Toray DuPont thickness 50 μm), and the copper foil was removed by etching (ferric chloride aqueous solution) to prepare a sample film. In addition, about the copper foil which performed the roughening process, the surface which roughened the copper foil was bonded together to the above-mentioned polyimide film, and the above-mentioned sample film was produced. A printed material (black circle with a diameter of 6 cm) was attached to one surface of the obtained resin layer, and the visibility of the printed material was judged from the opposite surface through the resin layer. “◎” indicates that the outline of the black circle of the printed material is clear when the length is 90% or more of the circumference, and “Clear” indicates that the outline of the black circle is clear when the length is 80% or more and less than 90% of the circumference. “O” (passed above), a black circle with a clear outline of 0 to less than 80% of the circumference and a broken outline were evaluated as “x” (failed). And the evaluation of the said visibility was made into evaluation of the copper foil surface state as it is.

(3) Yield The copper foil was bonded to both sides of a polyimide film (Kaneka thickness 25 μm, 50 μm, Toray DuPont thickness 50 μm), the copper foil was etched (ferric chloride aqueous solution), and L / S was 30 μm / 30 μm. An FPC with a circuit width of was prepared. In addition, about the copper foil which performed the roughening process, the surface which roughened the copper foil was bonded together to the above-mentioned polyimide film. After that, an attempt was made to detect a 20 μm × 20 μm square mark with a CCD camera through polyimide. “◎” when 9 times or more out of 10 times can be detected, “◯” when 7 to 8 times can be detected, “△” when 6 times can be detected, and when 5 times or less can be detected. Is “×”.
The conditions and evaluation of each test are shown in Tables 1-5.

(Evaluation results)
With respect to the polyimide base materials of the examples, the visibility could be easily and accurately evaluated at the laboratory level without actually producing them on the production line. The copper foil surface condition is evaluated by applying the visibility evaluations “◎”, “O” (passed above), and “×” (failed) as they are in the table. Could be easily and accurately evaluated.
Moreover, when the same test as the said Example was done using the mark with a width | variety as large as 1.0-2.0 mm instead of the said example, the figure with the bottom part shown in FIG. 3 as a lightness curve was obtained. FIG. 7 is a schematic diagram showing the configuration of the photographing unit and the measurement method of the brightness curve when evaluating the brightness curve when the mark width is 1.0 to 2.0 mm. In this case as well, the same results as in the above example were obtained, and as in the above example, the visibility of the polyimide base material was evaluated easily and accurately at the laboratory level without actually manufacturing it on the manufacturing line. As a result, the surface state of the copper foil could be easily and accurately evaluated.

DESCRIPTION OF SYMBOLS 10 Copper foil surface state evaluation apparatus 11 Imaging | photography means 12 Computer (Observation point-lightness graph preparation means, copper foil surface state evaluation means, smoothing processing means)
13 Display means 14 Illumination means 15 Stage 16 Mark 17 Transparent substrate

  The present invention relates to a copper foil surface state evaluation apparatus, a copper foil surface state evaluation program, a computer-readable recording medium on which the program is recorded, and a copper foil surface state evaluation method.

  In a small electronic device such as a smartphone or a tablet PC, a flexible printed wiring board (hereinafter referred to as FPC) is adopted because of easy wiring and light weight. In recent years, with the enhancement of functions of these electronic devices, the signal transmission speed has been increased, and impedance matching has become an important factor in FPC. As a measure for impedance matching with respect to an increase in signal capacity, a resin insulation layer (for example, polyimide) serving as a base of an FPC has been increased in thickness. On the other hand, processing such as bonding to a liquid crystal substrate and mounting of an IC chip is performed on the FPC, but the alignment at this time is the resin insulation remaining after etching the copper foil in the laminate of the copper foil and the resin insulating layer Since it is performed through a positioning pattern that is visible through the layer, the visibility of the resin insulating layer and the surface state of the copper foil laminated on the resin insulating layer that affects the resin insulating layer are important.

  As a method for evaluating the visibility of such a resin insulating layer, in Patent Document 1, an image taken through a resin insulating layer with a CCD camera is observed and evaluated. In Patent Document 2, it is evaluated whether or not a test pattern is distorted in an image taken by a CCD camera from an angle of 30 ° with respect to the horizontal plane of the resin insulating layer to be evaluated.

JP 2003-309336 A JP 2006-001056 A

However, in the case of simply observing an image by observing with a CCD camera as in Patent Document 1, there is a limit to the accuracy of the visibility evaluation. In reality, it is impossible to determine whether or not the provided mark can be visually recognized through the transparent base material, which is problematic in terms of manufacturing cost. The same applies to a method of evaluating whether or not a test pattern is distorted in the image as in Patent Document 2. And if the precision of visibility evaluation is low in this way, the precision of the evaluation of the surface state of the copper foil laminated | stacked on a resin insulating layer will also become low.
The present invention relates to a copper foil surface state evaluation apparatus capable of efficiently and accurately evaluating the surface state of a copper foil, a copper foil surface state evaluation program, a computer-readable recording medium on which the program is recorded, and A method for evaluating the surface state of a copper foil is provided.

  As a result of intensive studies, the present inventors have bonded the surface-treated surface side of the surface-treated copper foil to at least one surface of the transparent substrate, and then removed the surface-treated copper foil by etching. The mark existing under the transparent base material after removing the copper foil by etching is photographed through the transparent base material, and the brightness near the mark end portion drawn in the observation point-lightness graph obtained from the image of the mark part. Focusing on the magnitude of the change in the curve and evaluating the magnitude of the change in the brightness curve, the visibility of the transparent substrate can be improved without being affected by the type of transparent substrate and the thickness of the transparent substrate. It was found that the surface state of the copper foil laminated on the transparent substrate can be efficiently and accurately evaluated.

  The present invention completed on the basis of the above knowledge, in one aspect, after the surface-treated surface side of the surface-treated copper foil is bonded to at least one surface of the transparent substrate, the surface-treated copper foil is removed by etching. And the imaging means for photographing the mark existing under the transparent base material after the surface-treated copper foil is removed by etching through the transparent base material, and the image obtained by the photographing were observed An observation point-lightness graph preparation means for measuring the lightness of each observation point along a direction perpendicular to the direction in which the mark extends to create an observation point-lightness graph, and an end of the mark in the observation point-lightness graph To evaluate the visibility of the transparent substrate using a brightness curve generated over the portion without the mark, and evaluate the surface state of the copper foil based on the visibility evaluation result A copper foil surface state evaluation device comprising a foil surface state evaluation means, wherein the copper foil surface state evaluation means includes a top average value Bt of a brightness curve generated from an end portion of the mark to a portion without the mark, and An evaluation device for the surface state of a copper foil that evaluates visibility using a difference ΔB (ΔB = Bt−Bb) from the bottom average value Bb and evaluates the surface state of the copper foil based on the evaluation result of the visibility It is.

In one embodiment of the copper foil surface state evaluation apparatus according to the present invention, the copper foil surface state evaluation means includes a top average value Bt and a bottom average value of a brightness curve generated from an end portion of the mark to a portion without the mark. A value ΔB (ΔB = Bt−Bb) with respect to Bb and a value indicating a position of an intersection closest to the mark among intersections of the brightness curve and Bt in the observation point-brightness graph, In the depth range from the intersection with Bt to 0.1 ΔB with reference to Bt, when the value indicating the position of the intersection closest to the mark among the intersections of the lightness curve and 0.1 ΔB is t2, the following Sv defined by equation (1);
Sv = (ΔB × 0.1) / (t1-t2) (1)
Is used to evaluate the visibility, and the surface state of the copper foil is evaluated based on the visibility evaluation result.

  In another embodiment, the copper foil surface state evaluation apparatus according to the present invention further includes smoothing processing means for reducing variations in brightness of an image obtained by photographing by the photographing means, and the observation point-lightness graph is provided. A production means creates an observation point-lightness graph using the lightness after the smoothing process.

  In still another embodiment of the copper foil surface state evaluation apparatus according to the present invention, a line-shaped mark printed on a printed material laid under the transparent substrate is a mark present under the transparent substrate. The observation point-lightness graph preparation means measures and observes the lightness at each observation point along the direction perpendicular to the direction in which the observed line-shaped mark extends with respect to the image obtained by the photographing. Create a spot-lightness graph.

  In yet another embodiment of the copper foil surface state evaluation apparatus according to the present invention, in the visibility evaluation by the copper foil surface state evaluation means, the case where ΔB (ΔB = Bt−Bb) is 40 or more is good. Is determined.

  In another embodiment, the copper foil surface state evaluation apparatus according to the present invention is preferable in the case where ΔB (ΔB = Bt−Bb) is 50 or more in the visibility evaluation by the copper foil surface state evaluation means. Is determined.

  In yet another embodiment, the copper foil surface state evaluation apparatus according to the present invention determines that the Sv is 3.5 or higher in the visibility evaluation by the copper foil surface state evaluation means.

  In yet another embodiment, the copper foil surface state evaluation apparatus according to the present invention determines that the case where the Sv is 3.9 or more is good.

  In yet another embodiment, the copper foil surface state evaluation apparatus according to the present invention determines that the Sv is 5.0 or more as good.

  In another aspect, the present invention is a program for causing a computer to function as the copper foil surface state evaluation apparatus of the present invention.

  In still another aspect of the present invention, there is provided a computer-readable recording medium in which the evaluation program for the surface condition of the copper foil of the present invention is recorded.

  In yet another aspect of the present invention, after the surface-treated surface side of the surface-treated copper foil is bonded to at least one surface of the transparent substrate, the surface-treated copper foil is removed by etching. The mark existing under the transparent base material after removing the foil by etching is photographed through the transparent base material, and the image obtained by the photographing is in a direction perpendicular to the direction in which the observed mark extends. A lightness at each observation point is measured to produce an observation point-lightness graph. In the observation point-lightness graph, the transparent substrate is formed using a lightness curve generated from an end of the mark to a portion without the mark. Is a copper foil surface state evaluation method for evaluating the surface state of the copper foil based on the visibility evaluation result. The visibility of the transparent substrate is evaluated using the difference ΔB (ΔB = Bt−Bb) between the top average value Bt and the bottom average value Bb of the brightness curve generated from the part to the part where the mark is not present, It is the evaluation method of the surface state of copper foil which evaluates the surface state of copper foil based on the evaluation result of the visibility of material.

In one embodiment of the copper foil surface state evaluation method according to the present invention, the copper foil surface state evaluation is performed by measuring the top average value Bt and the bottom average value Bb of a brightness curve generated from an end portion of the mark to a portion without the mark. ΔB (ΔB = Bt−Bb) and the observation point-brightness graph, among the intersections of the lightness curve and Bt, the value indicating the position of the closest point to the mark is t1, and the lightness curve and Bt When the value indicating the position of the intersection closest to the mark among the intersections of the lightness curve and 0.1ΔB in the depth range from the intersection to Bt to 0.1ΔB is t2 1) Sv defined by the equation;
Sv = (ΔB × 0.1) / (t1-t2) (1)
Is used to evaluate the visibility of the transparent substrate, and the surface state of the copper foil is evaluated based on the evaluation result of the visibility of the transparent substrate.

In another embodiment of the method for evaluating the surface state of the copper foil of the present invention, the mark present under the transparent substrate is a line-shaped mark, and the observation point-lightness graph is obtained by the photographing. The image is produced by measuring the brightness at each observation point along the direction perpendicular to the direction in which the observed line-shaped mark extends.

In another embodiment, the evaluation method for the surface state of the copper foil of the present invention determines that the ΔB (ΔB = Bt−Bb) is 40 or more in the visibility evaluation as good.

In another embodiment of the method for evaluating the surface state of the copper foil of the present invention, in the visibility evaluation, the case where ΔB (ΔB = Bt−Bb) is 50 or more is determined to be good.

In another embodiment, the evaluation method of the surface state of the copper foil of the present invention determines that the case where the Sv is 3.5 or more in the visibility evaluation is good.

In another embodiment of the method for evaluating the surface state of the copper foil of the present invention, in the visibility evaluation, the case where the Sv is 3.9 or more is determined to be good.

In another embodiment, the evaluation method of the surface state of the copper foil of the present invention determines that the case where the Sv is 5.0 or more in the visibility evaluation is good.

  According to the present invention, the surface state of the copper foil is efficiently and accurately evaluated.

It is a schematic diagram of the evaluation apparatus of the surface state of the copper foil which concerns on embodiment of this invention. It is a flowchart of the evaluation method of the surface state of the copper foil which concerns on embodiment of this invention. It is a schematic diagram which defines Bt and Bb in case a mark width is about 1.3 mm. It is a schematic diagram which defines Bt and Bb in case a mark width is about 0.3 mm. It is a schematic diagram which defines t1, t2, and Sv. It is a schematic diagram showing the structure of the imaging | photography means and the measuring method of a lightness curve in the case of evaluation of the lightness curve in case the width | variety of a mark is 0.1-0.4 mm. It is a schematic diagram showing the structure of the imaging | photography means and the measuring method of a brightness curve in the case of evaluation of the brightness curve in case the width | variety of a mark is 1.0-2.0 mm.

(Copper foil surface state evaluation device, copper foil surface state evaluation method, copper foil surface state evaluation program, and recording medium)
FIG. 1 is a schematic diagram of a copper foil surface state evaluation apparatus 10 according to an embodiment of the present invention. The copper foil surface state evaluation apparatus 10 according to the embodiment of the present invention includes a photographing unit 11 that photographs the mark 16 existing under the transparent base material 17 provided on the stage 15 through the transparent base material 17. , A computer 12 that performs various processes based on image signals from the imaging means 11, a display means 13 that displays predetermined images and the like based on various signals from the computer 12, a transparent substrate 17 on the stage, and a mark 16 is provided with illumination means 14 for irradiating light. The transparent substrate 17 is not particularly limited, and may be a resin substrate such as glass or polyimide as long as it is transparent. In the present invention, the term “transparent” includes light transparency. The mark in the present invention may be a mark printed on a printed matter such as paper, or may be a copper wiring, and may take any form as long as it is a mark serving as a mark. The mark may be a printed material, a metal, an inorganic material, an organic material, or any mark. If the mark is in the form of a line, it is easy to create an observation point-lightness graph by measuring the lightness of each observation point along the direction crossing the observed mark for an image obtained by photographing. .

  The flexible printed wiring board (FPC) is subjected to processing such as bonding to a liquid crystal substrate and mounting of an IC chip. The alignment at this time is the resin insulation layer that remains after etching the copper foil of the copper-clad laminate. The visibility of the resin insulating layer is important because it is performed through a positioning pattern that is visible through the screen. And evaluation of the surface state of the copper foil which affects the visibility of such a resin insulation layer is needed. In the present invention, for the efficient and accurate visibility evaluation of such a resin insulating layer and the evaluation of the surface state of the copper foil, in the present invention, at least one surface is subjected to a surface treatment such as a roughening treatment. After the surface-treated metal foil is bonded to at least one surface of the transparent substrate from the surface side subjected to the surface treatment such as the roughening treatment, the metal foil is removed by etching. Although the said metal foil is not specifically limited, Copper foil, aluminum foil, nickel foil, copper alloy foil, nickel alloy foil, aluminum alloy foil, stainless steel foil, iron foil, iron alloy foil, etc. can be used.

  The imaging means 11 includes an imaging device, an image processing unit configured with an image processing circuit to which an output of the imaging device is input, a control unit configured with a control circuit that controls the image processing unit, a lens, and the like. Equipped with an optical system. As the photographing means 11, for example, a CCD camera or the like can be used. The photographing means 11 photographs the mark 16 existing under the transparent base material 17 provided on the stage 15 through the transparent base material 17 and acquires an image.

  The computer 12 performs various processes based on the image signal from the imaging unit 11. The computer 12 measures the lightness of each observation point along the direction perpendicular to the direction in which the observed mark 16 extends with respect to the image signal from the image pickup means 11, and creates an observation point-lightness graph. In the production means and the observation point-brightness graph, the visibility of the transparent substrate 17 is evaluated using a brightness curve generated from the end portion of the mark 16 to the portion where the mark 16 is not present, and copper is evaluated based on the visibility evaluation result. And a copper foil surface state evaluating means for evaluating the surface state of the foil.

  The computer 12 further includes smoothing processing means for reducing variations in lightness of the image obtained by photographing by the photographing means 11, and the observation point-lightness graph creating means uses the lightness after the smoothing processing to observe point-lightness. A graph may be created.

  Further, the mark 16 present under the transparent base material 17 is a line-shaped mark 16 printed on a printed material laid under the transparent base material 17, and the observation point-lightness graph preparation means is obtained by photographing. For the obtained image, the brightness at each observation point may be measured along the direction perpendicular to the direction in which the observed line-shaped mark 16 extends to create an observation point-lightness graph.

  The computer 12 includes a memory as storage means. In this memory, the digitized image from the imaging means 11, observation point-brightness graph preparation formula, visibility evaluation formula, copper foil surface condition evaluation formula, evaluation value at each stage, etc. are recorded in a computer-readable manner. (So-called preservation).

  Based on various signals from the computer 12, the display unit 13 displays a predetermined image, a numerical value, and the like such as an observation point-lightness graph, a visibility evaluation result, and a copper foil surface state evaluation result.

Next, the copper foil surface state evaluation method using the copper foil surface state evaluation apparatus 10 according to the above embodiment will be described with reference to the flowchart shown in FIG. The flow chart shown in FIG. 2 is an embodiment of the copper foil surface state evaluation method using the copper foil surface state evaluation apparatus 10 according to the present invention, and the copper foil surface state evaluation apparatus of the present invention. The evaluation method that can be realized in 10 is not limited to that shown in the flowchart of FIG. In particular, the visibility may not be evaluated by both measured values of ΔB and Sv, and the visibility may be evaluated only by ΔB. Further, although the smoothing process is performed on the image obtained by photographing in FIG. 2 before creating the observation point-lightness graph, the present invention is not limited to this, for example, after creating the observation point-lightness graph. You may go.
In the copper foil surface state evaluation method using the copper foil surface state evaluation apparatus 10, first, a surface-treated metal foil having at least one surface subjected to a surface treatment such as a roughening treatment is treated with a roughening treatment or the like. A transparent base material 17 prepared by removing the metal foil by etching after being bonded to at least one surface of the transparent base material from the surface-treated surface side is prepared. Next, the mark 16 existing under the transparent base material 17 is photographed by the photographing means 11 through the transparent base material 17. The signal of the image photographed by the photographing means 11 is sent to the computer 12. The observation point-lightness graph creating means of the computer 12 measures the lightness of each observation point along the direction perpendicular to the direction in which the observed mark 16 extends with respect to the image signal from the image pickup means 11, and the observation point-lightness graph. Is made. The surface condition evaluation means for the copper foil of the computer 12 evaluates the visibility of the transparent substrate 17 by the brightness curve generated from the end of the mark 16 to the portion without the mark 16 in the observation point-lightness graph. Based on the evaluation result, the surface state of the surface-treated metal foil that has been bonded to the transparent substrate 17 is evaluated. Conventionally, unless actually produced on the production line, it was impossible to determine whether or not the marks provided for alignment etc. could be seen through the transparent base material, and there was a problem in terms of production cost . However, if the copper foil surface state evaluation apparatus 10 according to the present invention is used, the above-described configuration easily and efficiently evaluates the visibility of the transparent substrate 17 even in the laboratory alone, thereby efficiently and accurately. It becomes possible to evaluate the surface state of the copper foil. For example, when the evaluation result of the visibility of the transparent substrate 17 is good, it can be evaluated that the surface state of the copper foil is good as it is.

  The copper foil surface state evaluation means of the computer 12 uses the difference ΔB (ΔB = Bt−Bb) between the top average value Bt and the bottom average value Bb of the brightness curve generated from the end of the mark 16 to the portion where the mark 16 is not present. The visibility is evaluated, and the surface state of the copper foil is evaluated using the evaluation result.

Moreover, the surface condition evaluation means of the copper foil of the computer 12 is the difference ΔB (ΔB = Bt−Bb) between the top average value Bt and the bottom average value Bb of the brightness curve generated from the end of the mark 16 to the portion where the mark 16 is not present. In the observation point-lightness graph, the value indicating the position of the intersection closest to the mark 16 among the intersections of the lightness curve and Bt (the value on the horizontal axis of the observation point-lightness graph) is t1, and the lightness curve In the depth range from the intersection with Bt to 0.1 ΔB with reference to Bt, a value indicating the position of the intersection closest to the mark among the intersections of the lightness curve and 0.1 ΔB (the side of the observation point-lightness graph) When the value of the axis is t2, Sv defined by the following equation (1):
Sv = (ΔB × 0.1) / (t1-t2) (1)
Visibility may be evaluated using, and the surface state of the copper foil may be evaluated using this evaluation result.
In the observation position-lightness graph described above, the horizontal axis indicates position information (pixel × 0.1), and the vertical axis indicates the value of brightness (gradation).
According to such a configuration, it is possible to easily and efficiently evaluate the visibility of the transparent base material 17 easily and efficiently even in the laboratory alone, and using this evaluation result, the copper foil can be easily and efficiently used only in the laboratory. The surface state of the film can be evaluated.

The computer 12 further includes smoothing processing means for reducing variations in lightness of the image obtained by photographing by the photographing means 11, and the observation point-lightness graph creating means uses the lightness after the smoothing processing to observe point-lightness. It is preferable to create a graph. Since smoothing processing by the smoothing processing means is performed on the data (original waveform) including lightness noise obtained from the image obtained by the photographing by the photographing means 11, the variation in the lightness is reduced. The visibility of the material 17 can be more accurately evaluated. The smoothing processing by the smoothing processing means can be performed by various smoothing programs. For example, smoothing processing by a second-third order polynomial fitting method, smoothing processing by Fourier transform, or smoothing processing by a moving average method is used. be able to. The smoothing process may be performed using various known smoothing programs. Further, the smoothing process of the brightness data may be performed for both the portion with the mark 16 and the portion without the mark 16, may be performed for the portion with the mark 16, may be performed on the portion without the mark 16, or may be performed partially. May be.
Note that an image obtained by photographing by the photographing unit 11 may be prepared in advance for an observation point-lightness graph of data (original waveform) including the lightness noise before performing the lightness smoothing process.

Moreover, in the visibility evaluation by the surface state evaluation means of the copper foil, when evaluating the visibility based only on the above ΔB value, the top average value of the brightness curve generated from the end of the mark 16 to the portion without the mark 16 When the difference ΔB between Bt and the bottom average value Bb is 40 or more, the visibility and the surface state of the copper foil may be determined to be good.
Furthermore, when the visibility is evaluated based on the ΔB value and the Sv value in the visibility evaluation by the surface state evaluation means of the copper foil, the top of the brightness curve generated from the end portion of the mark 16 to the portion where the mark 16 is not present. The difference ΔB between the average value Bt and the bottom average value Bb is 40 or more. In the observation point-lightness graph, a value indicating the position of the intersection closest to the mark among the intersections of the lightness curve and Bt (the observation point− In the depth range from the intersection of the lightness curve and Bt to 0.1 ΔB with reference to Bt, the value of the horizontal axis of the lightness graph is t1, and the mark 16 is the most in the intersection of the lightness curve and 0.1ΔB. When the value indicating the position of the closest intersection (the value of the horizontal axis of the observation point-lightness graph) is t2, it is determined that the visibility and the surface state of the copper foil are good when Sv is 3.5 or more. May be.
When Sv is 3.9 or more, preferably 4.5 or more, preferably 5.0 or more, more preferably 5.5 or more, it is more preferable to determine that the visibility and the surface state of the copper foil are good. . The upper limit of Sv is not particularly limited, but is, for example, 70 or less, 30 or less, 15 or less, or 10 or less.
When ΔB (ΔB = Bt−Bb) is 50 or more, it is preferable to determine that the visibility and the surface state of the copper foil are good, and when it is 60 or more, the visibility and the surface state of the copper foil are good. It is more preferable to judge. The upper limit of ΔB is not particularly limited, but is, for example, 100 or less, 80 or less, or 70 or less. According to such an evaluation, the visibility of the transparent base material 17 can be efficiently and accurately evaluated, and the evaluation of the surface state of the copper foil can be performed efficiently and accurately using this evaluation result. be able to.

Here, “top average value Bt of the lightness curve”, “bottom average value Bb of the lightness curve”, and “t1”, “t2”, and “Sv” described later will be described with reference to the drawings. For the “bottom average value Bb of the lightness curve”, the width of the mark is increased (for example, the width of the mark is 0.7 mm or more, for example, 0.8 mm or more, for example, 5 mm or less, 4 mm or less, for example, about 1.3 mm). And the mark width is reduced (for example, the mark width is 0.01 mm or more, 0.05 mm or more, 0.1 mm or more, 0.8 mm or less, 0.7 mm or less, 0.00 mm or less). Since the definition is different from that of 6 mm or less, for example, 0.3 mm, each case will be described.
FIG. 3 is a schematic diagram for defining Bt and Bb when the mark width is increased (about 1.3 mm). The “mark” in FIG. 3 indicates a line-like mark (width of about 1.3 mm) of the printed matter observed in the image obtained by photographing with the CCD camera. A curve drawn so as to overlap the mark indicates a brightness curve generated from the end of the mark to a portion without the mark in the observation point-lightness graph. As shown in FIG. 3, the “top average value Bt of the brightness curve” is the average of the brightness when measured at 5 locations (total 10 locations on both sides) at 30 μm intervals from the positions 100 μm away from the end positions on both sides of the mark. Indicates the value. The “bottom average value Bb of the lightness curve” indicates an average value of lightness when 11 positions are measured at intervals of 100 μm from a position inside 100 μm from the end position of the mark. Note that the interval between observation points for measuring the average value of the brightness can be appropriately selected in the range of 1 μm to 500 μm depending on the shape of the brightness curve. In order to avoid the bias of the observation points, it is preferable that the intervals between the observation points are substantially equal or equal. Note that the intervals between the observation points do not have to be substantially equal and may not be equal. Further, it is considered that the wider the measurement interval, the more the influence of a specific observation point can be eliminated and the error due to the observation point can be reduced.
FIGS. 4A and 4B are schematic diagrams for defining Bt and Bb when the mark width is about 0.3 mm. When the width of the mark is about 0.3 mm, the bottom is the same as in the case of a V-shaped brightness curve as shown in FIG. 4A and the case of about 1.3 mm as shown in FIG. May result in a lightness curve having In any case, the “top average value Bt of the lightness curve” is 5 locations at intervals of 30 μm from the positions 50 μm away from the end positions on both sides of the mark, as in the case where the mark width is about 1.3 mm ( The average value of the brightness when measured at 10 locations on both sides). On the other hand, the “bottom average value Bb of the lightness curve” indicates the minimum value of lightness at the tip of the V-shaped valley when the lightness curve is V-shaped as shown in FIG. When it has the bottom of (b), the value of the center part of about 0.3 mm is shown. Note that the interval between observation points for measuring the average value of the brightness can be appropriately selected in the range of 1 μm to 500 μm depending on the shape of the brightness curve. In order to avoid the bias of the observation points, it is preferable that the intervals between the observation points are substantially equal or equal. Note that the intervals between the observation points may not be substantially equal, and may not be equal. Further, it is considered that the wider the measurement interval, the more the influence of a specific observation point can be eliminated and the error due to the observation point can be reduced.
FIG. 5 is a schematic diagram for defining t1, t2, and Sv. “T1 (pixel × 0.1)” is a value indicating an intersection point closest to the line-shaped mark among intersection points of the lightness curve and Bt and a position of the intersection point (value on the horizontal axis of the observation point-lightness graph) ). “T2 (pixel × 0.1)” is the line-shaped mark among the intersections of the lightness curve and 0.1ΔB in the depth range from the intersection of the lightness curve and Bt to 0.1ΔB with reference to Bt. And the value (the value on the horizontal axis of the observation point-brightness graph) indicating the position of the intersection closest to. At this time, regarding the slope of the brightness curve indicated by the line connecting t1 and t2, Sv (gradation / pixel × 0.1) calculated by 0.1 ΔB in the y-axis direction and (t1−t2) in the x-axis direction. ). One pixel on the horizontal axis corresponds to a length of 10 μm. Further, Sv is measured on both sides of the mark, and a small value is adopted. Further, when the shape of the lightness curve is unstable and there are a plurality of the “intersections between the lightness curve and Bt”, the intersection closest to the mark is adopted.
In the image taken by the photographing means 11, the lightness is high in a portion where no mark is attached, but the lightness is lowered as soon as the mark end is reached. If the visibility of the transparent substrate 17 is good, such a lowered state of brightness is clearly observed. On the other hand, if the visibility of the transparent substrate 17 is poor, the lightness does not suddenly drop from “high” to “low” in the vicinity of the end of the mark, but the state of decline is moderate and the state of lightness decline is reduced. It will be unclear.
Based on such knowledge, the present invention places an observation mark obtained from the image of the mark portion taken by the photographing means 11 through the transparent base material 17, for example, with a printed matter with a mark placed under the transparent base material 17. -The brightness curve near the edge of the mark drawn in the brightness graph is controlled. More specifically, the difference ΔB (ΔB = Bt−Bb) between the top average value Bt and the bottom average value Bb of the lightness curve is set to 40 or more, and in the observation point-lightness graph, among the intersections of the lightness curve and Bt, Depth range from the intersection of the lightness curve and Bt to 0.1 ΔB on the basis of Bt, where t1 is the value indicating the position of the intersection closest to the line mark (value on the horizontal axis of the observation point-lightness graph) , When the value indicating the position of the intersection closest to the mark among the intersections of the lightness curve and 0.1 ΔB (the value of the observation point—the horizontal axis of the lightness graph) is t2, By evaluating the defined Sv, it is possible to accurately evaluate the visibility of the transparent substrate, and it is possible to efficiently and more accurately evaluate the surface state of the copper foil using this evaluation result. It is preferable to determine that the visibility and the surface state of the copper foil are good when Sv is 3.5 or more. When Sv is 3.9 or more, preferably 4.5 or more, preferably 5.0 or more, more preferably 5.5 or more, it is more preferable to determine that the visibility and the surface state of the copper foil are good. . Further, when ΔB is preferably 50 or more, it is more preferable to determine that the visibility and the surface state of the copper foil are good, and preferably, when ΔB is 60 or more, the visibility and the surface state of the copper foil are determined to be good. Good. The upper limit of ΔB is not particularly limited, but is, for example, 100 or less, 80 or less, or 70 or less. The upper limit of Sv is not particularly limited, but is, for example, 70 or less, 30 or less, 15 or less, or 10 or less. According to such a configuration, the boundary between the mark and the non-mark portion becomes clearer, the positioning accuracy is improved, the error due to the mark image recognition is reduced, and the alignment can be performed more accurately. Therefore, when the values of Sv and ΔB are within the range of the values of Sv and ΔB described above, it may be determined that the surface state of the copper foil is good.

  In addition, by causing the computer to execute the processing procedure as described above, the visibility of the transparent substrate can be efficiently and accurately evaluated, and the surface of the copper foil can be efficiently and accurately evaluated using the evaluation result. A state assessment can be performed.

  Furthermore, by using this program recorded on a recording medium such as an optical or magnetic disk so that it can be read by a computer, this program can be realized on other computers, and the same effects as the above-described processing procedure can be obtained. .

As Examples A1 to 30 and Examples B1 to 14, various copper foils were prepared, and plating treatment was performed on one surface under the conditions described in Table 1 as a roughening treatment.
After performing the above-mentioned roughening plating process, the plating process for the following heat-resistant layer and rust prevention layer formation was performed about Example A1-10, 12-27, Example B3, 4, 6, 9-15. .
The conditions for forming the heat-resistant layer 1 are shown below.
Liquid composition: Nickel 5-20 g / L, cobalt 1-8 g / L
pH: 2-3
Liquid temperature: 40-60 degreeC
Current density: 5 to 20 A / dm ²
Coulomb amount: 10-20 As / dm ²
A heat-resistant layer 2 was formed on the copper foil provided with the heat-resistant layer 1. For Examples B5, 7, and 8, the rough plating treatment was not performed, and the heat-resistant layer 2 was directly formed on the prepared copper foil. The conditions for forming the heat-resistant layer 2 are shown below.
Liquid composition: nickel 2-30 g / L, zinc 2-30 g / L
pH: 3-4
Liquid temperature: 30-50 degreeC
Current density: 1 to ^{2 A} / dm ²
Coulomb amount: 1-2 As / dm ²
On the copper foil which gave the said heat-resistant layers 1 and 2, the antirust layer was further formed. The conditions for forming the rust preventive layer are shown below.
Liquid composition: potassium dichromate 1-10 g / L, zinc 0-5 g / L
pH: 3-4
Liquid temperature: 50-60 degreeC
Current density: 0 to ^{2 A} / dm ² (for immersion chromate treatment)
Coulomb amount: 0 to ^{2 As} / dm ² (for immersion chromate treatment)
On the copper foil which gave the said heat-resistant layers 1 and 2 and a rust prevention layer, the weathering layer was further formed. The formation conditions are shown below.
As a silane coupling agent having an amino group, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane (Example A17, 24-27), N-2- (aminoethyl) -3-aminopropyltri Ethoxysilane (Examples A1 to 16), N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane (Examples A18, 28, 29), 3-aminopropyltrimethoxysilane (Example A19), 3 -Aminopropyltriethoxysilane (Examples A20, 21), 3-triethoxysilyl-N- (1,3-dimethyl-butylidene) propylamine (Example A22), N-phenyl-3-aminopropyltrimethoxysilane In (Example A23), coating and drying were performed to form a weather-resistant layer. These silane coupling agents can be used in combination of two or more. Similarly, in Examples B1 to 15, coating and drying were performed with N-2- (aminoethyl) -3-aminopropyltrimethoxysilane to form a weather resistant layer.

In addition, the rolled copper foil was manufactured as follows. After manufacturing the copper ingot of the composition shown in Table 2 and performing hot rolling, annealing and cold rolling of a continuous annealing line at 300 to 800 ° C. were repeated to obtain a rolled sheet having a thickness of 1 to 2 mm. This rolled sheet was annealed in a continuous annealing line at 300 to 800 ° C. and recrystallized, and finally cold-rolled to the thickness shown in Table 2 to obtain a copper foil. “Tough pitch copper” in the “Type” column of Table 2 indicates tough pitch copper standardized in JIS H3100 C1100, and “Oxygen-free copper” indicates oxygen-free copper standardized in JIS H3100 C1020. “Tough pitch copper + Ag: 100 ppm” means that 100 mass ppm of Ag is added to tough pitch copper.
The electrolytic copper foil used was an electrolytic copper foil HLP foil manufactured by JX Nippon Mining & Metals. When electrolytic polishing or chemical polishing was performed, the plate thickness after electrolytic polishing or chemical polishing was described.
Table 2 lists the points of the copper foil preparation process before the surface treatment. “High gloss rolling” means that the final cold rolling (cold rolling after the final recrystallization annealing) was performed at the value of the oil film equivalent. “Normal rolling” means that the final cold rolling (cold rolling after the final recrystallization annealing) was performed at the oil film equivalent value described. “Chemical polishing” and “electropolishing” mean the following conditions.
“Chemical polishing” was performed using an etching solution of 1 to 3% by mass of H ₂ SO ₄ , 0.05 to 0.15% by mass of H ₂ O ₂ , and the remaining water, and the polishing time was 1 hour.
“Electropolishing” is a condition of phosphoric acid 67% + sulfuric acid 10% + water 23%, voltage 10 V / cm ² , and the time shown in Table 2 (when electropolishing for 10 seconds, the polishing amount is 1 to 2 μm. ).

About each sample of the Example produced as mentioned above, various evaluation was performed as follows using the evaluation apparatus of the surface state of the copper foil of the structure similar to what was shown in FIG.
(1) Lightness curve A copper foil was bonded to both sides of a polyimide film (Kaneka thickness 25 μm, 50 μm, Toray DuPont thickness 50 μm), and the copper foil was removed by etching (ferric chloride aqueous solution) to prepare a sample film. . Subsequently, a printed material on which a line-shaped black mark was printed was laid under the sample film, and the printed material was photographed with a CCD camera through the sample film. The width of the mark used here was 0.1 to 0.4 mm. Next, in the observation point-brightness graph prepared by measuring the lightness of each observation point along the direction perpendicular to the direction in which the observed line-shaped mark extends, for an image obtained by photographing with a computer, The brightness curve generated from the end of the mark to the portion without the mark, and ΔB and t1, t2, and Sv were measured. FIG. 6 is a schematic diagram showing the configuration of the photographing means used at this time and the measurement method of the brightness curve.
ΔB, t1, t2, and Sv were measured by the following photographing means as shown in FIG. One pixel on the horizontal axis corresponds to a length of 10 μm.
The photographing means includes a CCD camera, a stage (white) on which a polyimide substrate is placed with a marked paper underneath, an illumination power source for irradiating light onto the photographing portion of the polyimide substrate, and a paper with a mark to be photographed. A transporter (not shown) for transporting the evaluation polyimide substrate placed below onto the stage is provided. The main specifications of the photographing means are as follows:
・ Photographing means: Nireco Corporation sheet inspection device Mujken
CCD camera: 8192 pixels (160 MHz), 1024 gradation digital (10 bits)
・ Power supply for lighting: High-frequency lighting power supply (power supply unit x 2)
・ Lighting: Fluorescent lamp (30W)
For the lightness shown in FIG. 6, 0 means “black”, lightness 255 means “white”, and the gray level from “black” to “white” (black and white shading, gray scale) Is divided into 256 gradations for display.
In addition, since the used mark width was as small as 0.1 to 0.4 mm, the produced brightness curve has a V shape as shown in FIG. 4A or a bottom as shown in FIG. It became V type which has.

(2) Evaluation of visibility (resin transparency) and surface condition of copper foil;
The copper foil was bonded to both surfaces of a polyimide film (Kaneka thickness 25 μm, 50 μm, Toray DuPont thickness 50 μm), and the copper foil was removed by etching (ferric chloride aqueous solution) to prepare a sample film. In addition, about the copper foil which performed the roughening process, the surface which roughened the copper foil was bonded together to the above-mentioned polyimide film, and the above-mentioned sample film was produced. A printed material (black circle with a diameter of 6 cm) was attached to one surface of the obtained resin layer, and the visibility of the printed material was judged from the opposite surface through the resin layer. “◎” indicates that the outline of the black circle of the printed material is clear when the length is 90% or more of the circumference, and “Clear” indicates that the outline of the black circle is clear when the length is 80% or more and less than 90% of the circumference. “O” (passed above), a black circle with a clear outline of 0 to less than 80% of the circumference and a broken outline were evaluated as “x” (failed). And the evaluation of the said visibility was made into evaluation of the copper foil surface state as it is.

(3) Yield The copper foil was bonded to both sides of a polyimide film (Kaneka thickness 25 μm, 50 μm, Toray DuPont thickness 50 μm), the copper foil was etched (ferric chloride aqueous solution), and L / S was 30 μm / 30 μm. An FPC with a circuit width of was prepared. In addition, about the copper foil which performed the roughening process, the surface which roughened the copper foil was bonded together to the above-mentioned polyimide film. After that, an attempt was made to detect a 20 μm × 20 μm square mark with a CCD camera through polyimide. “◎” when 9 times or more out of 10 times can be detected, “◯” when 7 to 8 times can be detected, “△” when 6 times can be detected, and when 5 times or less can be detected. Is “×”.
The conditions and evaluation of each test are shown in Tables 1-5.

(Evaluation results)
With respect to the polyimide base materials of the examples, the visibility could be easily and accurately evaluated at the laboratory level without actually producing them on the production line. The copper foil surface condition is evaluated by applying the visibility evaluations “◎”, “O” (passed above), and “×” (failed) as they are in the table. Could be easily and accurately evaluated.
Moreover, when the same test as the said Example was done using the mark with a width | variety as large as 1.0-2.0 mm instead of the said example, the figure with the bottom part shown in FIG. 3 as a lightness curve was obtained. FIG. 7 is a schematic diagram showing the configuration of the photographing unit and the measurement method of the brightness curve when evaluating the brightness curve when the mark width is 1.0 to 2.0 mm. In this case as well, the same results as in the above example were obtained, and as in the above example, the visibility of the polyimide base material was evaluated easily and accurately at the laboratory level without actually manufacturing it on the manufacturing line. As a result, the surface state of the copper foil could be easily and accurately evaluated.

DESCRIPTION OF SYMBOLS 10 Copper foil surface state evaluation apparatus 11 Imaging | photography means 12 Computer (Observation point-lightness graph preparation means, copper foil surface state evaluation means, smoothing processing means)
13 Display means 14 Illumination means 15 Stage 16 Mark 17 Transparent substrate

Claims (12)

After the surface-treated surface side of the surface-treated copper foil is bonded to at least one surface of the transparent substrate, the surface-treated copper foil is removed by etching, and the surface-treated copper foil is removed by etching. Photographing means for photographing the mark existing under the material through the transparent substrate;
With respect to the image obtained by the photographing, an observation point-lightness graph creating means for measuring the lightness of each observation point along a direction perpendicular to the direction in which the observed mark extends, and creating an observation point-lightness graph;
In the observation point-lightness graph, the visibility of the transparent substrate is evaluated using a brightness curve generated from an end of the mark to a portion where the mark is not present, and the surface of the copper foil is evaluated based on the visibility evaluation result. Copper foil surface state evaluation means for evaluating the state,
Is an evaluation device for the surface state of a copper foil provided with
The copper foil surface state evaluation means,
The visibility of the transparent substrate is evaluated by using the difference ΔB (ΔB = Bt−Bb) between the top average value Bt and the bottom average value Bb of the brightness curve generated from the end portion of the mark to the portion without the mark. The evaluation apparatus of the surface state of copper foil which evaluates the surface state of copper foil based on the evaluation result of the visibility of the said transparent base material. The copper foil surface state evaluation means,
A difference ΔB (ΔB = Bt−Bb) between a top average value Bt and a bottom average value Bb of a brightness curve generated from an end portion of the mark to a portion without the mark;
In the observation point-lightness graph, the value indicating the position of the intersection closest to the mark among the intersections of the lightness curve and Bt is t1, and from the intersection of the lightness curve and Bt to 0.1 ΔB based on Bt. Sv defined by the following equation (1) when the value indicating the position of the intersection closest to the mark among the intersections of the lightness curve and 0.1 ΔB in the depth range is t2.
Sv = (ΔB × 0.1) / (t1-t2) (1)
The evaluation apparatus of the surface state of the copper foil of Claim 1 which evaluates the visibility of the said transparent base material using the, and evaluates the surface state of a copper foil based on the evaluation result of the visibility of the said transparent base material. For an image obtained by photographing by the photographing means, further comprising a smoothing processing means for reducing variations in brightness,
The evaluation apparatus of the surface state of the copper foil of Claim 1 or 2 with which the said observation point-lightness graph preparation means produces an observation point-lightness graph using the said lightness after the said smoothing process. The mark present under the transparent substrate is a line-shaped mark printed on a printed material laid under the transparent substrate,
The observation point-lightness graph preparation means measures the lightness of each observation point along the direction perpendicular to the direction in which the observed line-shaped mark extends with respect to the image obtained by the photographing. The evaluation apparatus of the surface state of the copper foil in any one of Claims 1-3 which produces a graph.   In the visibility evaluation by the said copper foil surface state evaluation means, when the said (DELTA) B ((DELTA) B = Bt-Bb) is 40 or more, it determines with the surface state of the copper foil in any one of Claims 1-4 determined favorable. Evaluation device.   The evaluation apparatus of the surface state of the copper foil according to claim 5, wherein in the visibility evaluation by the copper foil surface state evaluation unit, the case where the ΔB (ΔB = Bt−Bb) is 50 or more is determined to be good.   The visibility evaluation apparatus by the said copper foil surface state evaluation means WHEREIN: The evaluation apparatus of the surface state of the copper foil in any one of Claims 2-6 which determines that the case where said Sv becomes 3.5 or more is favorable.   The evaluation apparatus of the copper foil surface state according to claim 7, wherein in the visibility evaluation by the copper foil surface state evaluating means, the case where the Sv is 3.9 or more is determined as good.   The visibility evaluation apparatus by the said copper foil surface state evaluation means WHEREIN: The evaluation apparatus of the copper foil surface state of Claim 8 which determines the case where Sv is 5.0 or more as favorable.   The program for functioning a computer as an evaluation apparatus of the surface state of the copper foil in any one of Claims 1-9.   A computer-readable recording medium on which the program according to claim 10 is recorded. After the surface-treated surface side of the surface-treated copper foil is bonded to at least one surface of the transparent substrate, the surface-treated copper foil is removed by etching, and the surface-treated copper foil is removed by etching. Photograph the mark that exists under the material through the transparent substrate,
For the image obtained by the photographing, an observation point-brightness graph is prepared by measuring the brightness for each observation point along the direction perpendicular to the direction in which the observed mark extends,
In the observation point-lightness graph, the visibility of the transparent substrate is evaluated using a brightness curve generated from the end of the mark to a portion where the mark is not present, and based on the evaluation result of the visibility of the transparent substrate. It is an evaluation method of the surface state of the copper foil for evaluating the surface state of the copper foil,
The copper foil surface state evaluation is
The visibility of the transparent substrate is evaluated by using the difference ΔB (ΔB = Bt−Bb) between the top average value Bt and the bottom average value Bb of the brightness curve generated from the end portion of the mark to the portion without the mark. The evaluation method of the surface state of copper foil which evaluates the surface state of copper foil based on the evaluation result of the visibility of the said transparent base material.