Test device and test method for the peel strength of an insulation material from a copper foil

Abstract

This application relates to a testing apparatus and method for testing the peel strength between insulating materials and copper foil. The testing apparatus includes a cutting fixture, a cutting blade, and a peel strength testing device. The cutting fixture has several test strip frames. The cutting blade includes a housing and a blade installed inside the housing. During cutting, the cutting fixture presses against a flexible copper foil substrate. The flexible copper foil substrate includes an insulating material layer and a copper foil layer pressed onto the insulating material layer. The blade adheres to the inner wall of the test strip frames to cut the copper foil layer on the flexible copper foil substrate, obtaining a copper foil test strip. The peel strength testing device is used to peel the copper foil test strip from the insulating material layer, thereby measuring the peel strength between the copper foil layer and the insulating material layer. This testing apparatus can accurately measure the peel strength between the insulating material and the copper foil, improving testing efficiency.

Description

Technical Field

[0001] This application relates to testing technology for flexible copper foil, specifically to a testing device and method for testing the peel strength between insulating materials and copper foil. Background Technology

[0002] Currently, peel strength testing between the insulating material and copper foil in FCCL (Flexible Copper Foil) substrates typically requires circuit fabrication. The fabrication process involves: FCCL material cutting, dry film lamination, circuit exposure, circuit development, and circuit etching. This wet process easily generates water contamination, making it unacceptable to conduct such processes within factory premises in areas with strict pollution control measures. When peel strength testing between the insulating material and copper foil is required, outsourcing is necessary, which is not only costly but also time-consuming, severely impacting product manufacturing and R&D progress. Summary of the Invention

[0003] To overcome the above-mentioned defects, this application provides a testing device for the peel strength of insulating material and copper foil. During the peel strength test of the insulating material layer and copper foil layer using this testing device, no pollution is generated, so there is no need to outsource the testing and the testing efficiency is improved.

[0004] The technical solution adopted by this application to solve its technical problem is:

[0005] A testing device for the peel strength of insulating material to copper foil includes a cutting fixture, a cutting blade, and a peel strength testing device. The cutting fixture has several test strip frames. The cutting blade includes a housing and a blade installed inside the housing. During cutting, the cutting fixture is pressed onto a flexible copper foil substrate. The flexible copper foil substrate includes an insulating material layer and a copper foil layer pressed onto the insulating material layer. The blade adheres to the inner sidewall of the test strip frames to cut the copper foil layer on the flexible copper foil substrate to obtain a copper foil test strip. The peel strength testing device is used to peel the copper foil test strip off the insulating material layer, thereby measuring the peel strength between the copper foil layer and the insulating material layer.

[0006] Optionally, the cutting fixture is a square cutting fixture made of stainless steel, with a thickness of 2-5 mm, a length of 200-220 mm, and a width of 60-100 mm, and the peel strength testing equipment is a universal testing machine.

[0007] Optionally, the test frame is a hollow structure formed on the cutting fixture, and the test frame is a rectangular structure. The test frame includes a first test frame and a second test frame. The cutting fixture is provided with a plurality of parallel first test frames and a plurality of parallel second test frames. The width of the first test frame is 2.5±0.5mm and the length is 160-200mm. The width of the second test frame is 5±0.5mm and the length is 160-200mm.

[0008] Optionally, the spacing between two adjacent test frames is 5-10 mm, the upper surface of the test frame is ground flat, the upper surface of the cutting fixture has two parallel long sides and two parallel short sides, the distance of the long side from the nearest test frame is 5-10 mm, and the distance of the short side from the nearest test frame is greater than or equal to 10 mm.

[0009] Optionally, the flexible copper foil substrate is a single-layer copper foil substrate or a double-layer copper foil substrate. When the flexible copper foil substrate is a single-layer copper foil substrate, the flexible copper foil substrate includes a copper foil layer and an insulating material layer that are pressed together, or the flexible copper foil substrate includes a copper foil layer, an adhesive layer, and an insulating material layer that are sequentially bonded together. When the flexible copper foil substrate is a double-layer copper foil substrate, the flexible copper foil substrate includes a copper foil layer, an insulating material layer, and a copper foil layer that are sequentially bonded together, or the flexible copper foil substrate includes a copper foil layer, an adhesive layer, an insulating material layer, an adhesive layer, and a copper foil layer that are sequentially bonded together.

[0010] Optionally, the blade is mounted obliquely inside the housing, with the lower end of the blade extending out of the housing. A roller is mounted on the housing, and the roller is connected to a first motor that can drive the roller to rotate. The first motor is mounted inside the housing.

[0011] Optionally, the blade is adjustablely mounted in the housing via a knob connected to a second motor, which can rotate the knob to adjust the pressure of the blade, and the blade forms an angle of 30±5° with the lower surface of the housing.

[0012] This application also provides a method for testing the peel strength between insulating materials and copper foil, specifically including the following steps:

[0013] Step 1: Place the cutting fixture on the copper foil layer of the flexible copper foil substrate to be cut, with the copper foil test strip exposed at the test strip frame on the cutting fixture;

[0014] Step 2: Place the cutting blade on the cutting fixture and make the blade fit against the inner side wall of a test frame, with the lower end of the blade inserted into the copper foil layer;

[0015] Step 3: Start the cutting blade. The cutting blade moves in a straight line along the flexible copper foil substrate. The blade cuts through the copper foil layer it passes through. Adjust the position of the cutting blade so that the blade cuts through the copper foil test strip in the test strip frame in sequence.

[0016] Step 4: Take out the cut flexible copper foil substrate and bend it repeatedly at 90-180° along the cut line of the copper foil layer until the cut line of the copper foil layer is completely broken. At this time, the copper foil test strip of the same size as the test strip frame is separated from the main copper foil layer around its perimeter.

[0017] Step 5: Use a peel strength tester to peel the copper foil test strip off the insulating material layer to obtain the peel strength between the copper foil layer and the insulating material layer.

[0018] Optionally, in step 3, before starting the cutting tool, the cutting pressure of the blade is set to 5-35g. The cutting tool moves backward along the soft copper foil substrate. After the copper foil test strip is cut open around its perimeter, a diagonal line is cut at any end of the copper foil test strip using the blade.

[0019] Optionally, the cutting pressure is determined according to the thickness of the copper foil layer. When the thickness of the copper foil layer is 9±1μm, the cutting pressure is set to 7±1g; when the thickness of the copper foil layer is 12±1μm, the cutting pressure is set to 10±1g; when the thickness of the copper foil layer is 18±1μm, the cutting pressure is set to 15±1g; and when the thickness of the copper foil layer is 35±1μm, the cutting pressure is set to 30±1g.

[0020] The beneficial effects of this application are as follows: The testing device in this application includes a cutting fixture, a cutting blade, and a peel strength testing device. The cutting fixture is used to precisely control the size of the cut copper foil test strip and assists in the accurate positioning of the cutting blade. The cutting blade cuts the copper foil layer without cutting the insulating material layer, thereby obtaining a copper foil test strip that is disconnected from the main copper foil layer on all four sides. Finally, the peel strength testing device is used to peel the copper foil test strip from the insulating material layer to obtain the peel strength between the copper foil layer and the insulating material layer. Therefore, the entire testing process adopts a physical method and will not generate any pollution, especially water pollution, which is very environmentally friendly. Any company can complete the test internally, thereby saving testing costs and testing time, and facilitating the rapid advancement of product research and development and production processes. Attached Figure Description

[0021] Figure 1 This is a top view of the cutting fixture in this application;

[0022] Figure 2 This is a front view of the cutting fixture in this application;

[0023] Figure 3 This is a schematic diagram of the cutting fixture placed on a flexible copper foil substrate in this application;

[0024] Figure 4 This is a side view of the cutting tool in this application;

[0025] Figure 5 This is a top view of the cutting tool in this application;

[0026] Figure 6 This is one of the overlay diagrams of the flexible copper foil substrate in this application;

[0027] Figure 7 This is the second overlay diagram of the flexible copper foil substrate in this application;

[0028] Figure 8 This is the third overlay diagram of the flexible copper foil substrate in this application;

[0029] Figure 9 This is the fourth overlay diagram of the flexible copper foil substrate in this application;

[0030] In the diagram: 10-Cutting fixture, 11-First test frame, 12-Second test frame, 13-Long side, 14-Short side, 15-Bevel side, 20-Cutting blade, 21-Box, 22-Roller, 23-Blade, 24-Knob, 25-Power switch, 26-Digital display screen, 27-Adjustment key, 28-Start key, 30-Flexible copper foil substrate, 31-Copper foil layer, 32-Insulating material layer, 33-Adhesive layer. Detailed Implementation

[0031] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the embodiments of this application. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0032] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such uses of the terms can be interchanged where appropriate so that the embodiments of this application described herein can be implemented, for example, in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0033] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0034] Example: Figure 1-9 As shown, a testing device for the peel strength of insulating material to copper foil includes a cutting fixture 10, a cutting blade 20, and a peel strength testing device. The cutting fixture 10 is provided with a plurality of test strip frames. The cutting blade 20 includes a housing 21 and a blade 23 installed in the housing 21. During cutting, the cutting fixture 10 is pressed onto a flexible copper foil substrate 30. The flexible copper foil substrate 30 includes an insulating material layer 32 and a copper foil layer 31 pressed onto the insulating material layer 32. The blade 23 adheres to the inner sidewall of the test strip frame to cut the copper foil layer 31 on the flexible copper foil substrate 30 to obtain a copper foil test strip. The peel strength testing device is used to peel the copper foil test strip off the insulating material layer 32, thereby measuring the peel strength between the copper foil layer 31 and the insulating material layer 32.

[0035] The number of test frames on the cutting fixture 10 can be set as needed. The test frames are hollow structures, and their size is similar to that of the copper foil test strip to be peeled off. When the cutting fixture 10 is placed on the soft copper foil substrate 30, the copper foil test strip is exposed at the test frame. Then, the copper foil test strip is cut out along the inner wall of the test frame using the blade 23. By controlling the cutting force of the blade 23, only the surface copper foil layer 31 is cut without cutting the insulating material layer 32. To ensure that the insulating material layer 32 is not cut, the copper foil layer 31 can be partially cut off at all four sides during cutting. After cutting, the copper foil layer can be repeatedly bent at 90-180° along the cutting line to completely break the copper foil test strip at the cutting line. At this time, the copper foil test strip of the same size as the test frame is separated from the main copper foil layer at all four sides. Finally, the peel strength test equipment is used to peel the copper foil test strip off the insulating material layer 32, thereby obtaining the peel strength between the copper foil layer 31 and the insulating material layer 32. In this application, a cutting fixture 10 is used to precisely control the size of the cut copper foil test strip. A cutting blade 20 is used to cut the copper foil layer without cutting the insulating material layer, resulting in a copper foil test strip with broken edges. Finally, a peel strength test device is used to peel the copper foil test strip to obtain the peel strength between the copper foil layer and the insulating material layer. Therefore, the entire testing process uses physical methods without the use of any chemical agents, and will not produce any pollution, especially water pollution, making it very environmentally friendly. The test can be completed internally by the company, saving testing costs and time.

[0036] like Figure 1-2 As shown, the cutting fixture 10 is a square cutting fixture made of stainless steel. The cutting fixture 10 has a thickness of 2-5 mm, a length of 200-220 mm, and a width of 60-100 mm. The peel strength testing equipment is a universal testing machine. The cutting fixture 10 is made of stainless steel with smooth surfaces on both the top and bottom, making it easy to manufacture and durable. The peel strength testing equipment uses a universal testing machine commonly used in the field, so no additional equipment is needed. The universal testing machine is existing technology and will not be described in detail here.

[0037] like Figure 1 As shown, the test frame is a hollow structure formed on the cutting fixture 10, and the test frame is a rectangular structure. The test frame includes a first test frame 11 and a second test frame 12. The cutting fixture 10 is provided with a plurality of parallel first test frames 11 and a plurality of parallel second test frames 12. The width of the first test frame 11 is 2.5±0.5mm and the length is 160-200mm. The width of the second test frame 11 is 5±0.5mm and the length is 160-200mm. Figure 1The cutting fixture 10 has three parallel first test frames 11 and three parallel second test frames 12. Of course, different numbers of first test frames 11 and second test frames 12 can be designed according to the actual situation. Optionally, the width of the first test frame 11 is 2.5mm and the width of the second test frame 12 is 5mm. That is, copper foil test strips with widths of 2.5mm and 5mm are cut out by the cutting fixture 10. These two specifications of copper foil test strips are suitable for this physical peeling method.

[0038] The spacing between two adjacent test frames is 5-10 mm. The upper surface of each test frame is ground smooth. The upper surface of the cutting fixture 10 has two parallel long sides 13 and two parallel short sides 14. The distance between the long side 13 and the nearest test frame is 5-10 mm, and the distance between the short side 14 and the nearest test frame is greater than or equal to 10 mm. The upper surface of the test frames is ground smooth to prevent cuts to operators. Figure 1 As shown in the figure, the X direction is the length direction of the cutting fixture 10, the Y direction is the width direction of the cutting fixture 10, the so-called long side 13 refers to the two sides along the length direction of the cutting fixture 10, and the so-called short side 14 refers to the two sides along the width direction of the cutting fixture 10. There are blank spaces around the cutting fixture 10, and there are certain blank spaces between two adjacent test frames to ensure that the strength of the cutting fixture 10 meets the usage requirements.

[0039] The flexible copper foil substrate 30 can be a single-layer copper foil substrate or a double-layer copper foil substrate. When the flexible copper foil substrate 30 is a single-layer copper foil substrate, such as... Figure 6 As shown, the flexible copper foil substrate 30 includes a copper foil layer 31 and an insulating material layer 32 laminated together, or as shown in the figure. Figure 7 As shown, the flexible copper foil substrate 30 includes a copper foil layer 31, an adhesive layer 33, and an insulating material layer 32 sequentially bonded together; when the flexible copper foil substrate 30 is a double-layer copper foil substrate, as... Figure 8 As shown, the flexible copper foil substrate 30 includes a copper foil layer 31, an insulating material layer 32, and a copper foil layer 31 sequentially bonded together, or as shown in the figure. Figure 9As shown, the flexible copper foil substrate 30 includes a copper foil layer 31, an adhesive layer 33, an insulating material layer 32, an adhesive layer 33, and a copper foil layer 31 that are sequentially bonded together. Optionally, the adhesive layer 33 is a polypropylene thermosetting adhesive layer (AD layer), an epoxy resin thermosetting adhesive layer, or a polyurethane adhesive layer, and the insulating material layer 32 is one of a polyimide layer, a polyethylene terephthalate (PET) layer, a polyaniline (PAn) layer, a polyethylene naphthalate (PEN) layer, a triacetine (TAc) layer, a liquid crystal polymer (LCP) layer, and a polycarbonate (PC) resin layer. Preferably, it is a polyimide layer or a polyethylene terephthalate (PET) layer. That is, this testing device can meet the testing needs of both single-layer and double-layer copper foil substrates; it can meet the testing needs of both adhesive-coated and non-adhesive-coated copper foils.

[0040] like Figure 4 and 5 As shown, the blade 23 is installed obliquely inside the housing 21, with its lower end extending out of the housing 21. A roller 22 is mounted on the housing 21, connected to a first motor that drives the roller 22 to roll. The first motor is installed inside the housing 21. In use, the blade 23 is placed against the inner wall of the test strip frame, with its lower end piercing the copper foil layer 31. Then, the first motor drives the roller to move linearly along the cutting fixture 10, and the blade 23 cuts through the copper foil layer.

[0041] The blade 23 is adjustablely mounted inside the housing 21 via a knob 24. The knob 24 is connected to a second motor, and the second motor can rotate the knob 24 to adjust the pressure of the blade 23. The blade 23 forms an angle of 30±5° with the lower surface of the housing 21. Optionally, as... Figure 4 As shown, when the blade 23 contacts the copper foil layer 31, the angle α between the blade 23 and the copper foil layer 31 is 30°, so that the blade 23 can apply appropriate force to the copper foil layer 31; the second motor is also electrically connected to a force sensor, such as Figure 5As shown, the housing 21 is equipped with a power switch 25, a digital display screen 26, an adjustment key 27, and a start key 28. The power switch 25 is used to turn on the power to the cutting blade 20. The adjustment key 27 is used to adjust the pressure of the blade 23. The set pressure is displayed on the digital display screen 26. The start key 28 is used to start the cutting blade 20. The control center PLC controls the second motor to work according to the set pressure. The second motor rotates the knob 24 to clamp or release the blade 23, so that the blade 23 receives the appropriate pressure to cut the copper foil, just enough to cut the copper foil, but without cutting the insulating material layer 32.

[0042] The testing method of this testing device specifically includes the following steps:

[0043] Step 1: As Figure 3 As shown, the cutting fixture 10 is placed on the copper foil layer 31 of the soft copper foil substrate 30 to be cut, and the copper foil test strip is exposed at the test strip frame on the cutting fixture 10. Figure 3 The diagram shows three narrow copper foil test strips, each 160 mm long and 2.5 mm wide, and three wide copper foil test strips, each 160 mm long and 5 mm wide. During cutting, only a portion of the copper foil test strips can be cut as needed. The cutting fixture 10 can accurately and quickly position the cutting line, improving cutting efficiency and accuracy.

[0044] Step 2: As Figure 4 As shown, the cutting tool 20 is placed on the cutting fixture 10, and the blade 23 is attached to an inner wall of a test strip frame. The lower end of the blade 23 is inserted into the copper foil layer 31. The lower end of the blade 23 pierces the surface of the copper foil layer 31, and the copper foil layer 31 in contact with the blade 23 is cut by the running process of the cutting tool 20. Of course, the copper foil test strip can also be cut by manually holding the blade 23 along the inner wall of the test strip frame, or by using a commonly used laser cutting machine.

[0045] Step 3: Start the cutting blade 20. The cutting blade 20 moves linearly along the flexible copper foil substrate 30. The blade 23 cuts through the copper foil layer it passes through. Adjust the position of the cutting blade 20 so that the blade 23 cuts through the copper foil test strip within the test strip frame sequentially. In this embodiment, a first motor is used to drive the roller 22 to run, thereby driving the blade 23 to run. Figure 4 As shown, the lower end of the blade 23 forms an angle α of about 30° with the copper foil layer. The first motor drives the roller 22 to move backward, which makes it easier for the blade 23 to cut the copper foil. Of course, the box 21 can also be pushed manually.

[0046] Step 4: Take out the cut flexible copper foil substrate 30 and bend it repeatedly at 90-180° along the cut line of the copper foil layer to completely break the copper foil layer at the cut line. At this time, the copper foil test strip of the same size as the test strip frame is separated from the main copper foil layer. In order to prevent the insulation material layer 32 from being cut and seriously affecting the test results, the blade 23 will not completely cut the copper foil layer during the cutting process. After cutting, the copper foil test strip is completely separated from the main copper foil layer by repeatedly bending the copper foil test strip.

[0047] Step 5: Use a peel strength testing device to peel the copper foil test strip from the insulating material layer 32, thereby obtaining the peel strength between the copper foil layer 31 and the insulating material layer 32. In this embodiment, a universal testing machine is used for the glass strength testing device. By cutting a diagonal line at one end of the copper foil test strip to peel it open, the peeled copper foil test strip is connected to the universal testing machine, and the universal testing machine is used to peel the copper foil test strip from the insulating material layer, thereby obtaining the peel strength between the two.

[0048] In step 3, before activating the cutting tool 20, the cutting pressure of the blade 23 is set to 5-35g. The cutting tool 20 moves backward along the flexible copper foil substrate 30. After the copper foil test strip is cut open around its perimeter, the blade 23 is used to cut a diagonal line at any end of the copper foil test strip. Figure 1 As shown, a diagonal line is cut along the bevel 15 on the cutting fixture 10, so that the copper foil at the bevel angle curls up along the diagonal line, making it easier to tear the copper foil test strip.

[0049] Optionally, the cutting pressure is determined based on the thickness of the copper foil layer 31. When the thickness of the copper foil layer is 9±1μm, the cutting pressure is set to 7±1g; when the thickness is 12±1μm, the cutting pressure is set to 10±1g; when the thickness is 18±1μm, the cutting pressure is set to 15±1g; and when the thickness is 35±1μm, the cutting pressure is set to 30±1g. Experimental verification shows that setting corresponding pressure values ​​for copper foil layers of different thicknesses allows for the cutting of the copper foil layer without cutting the insulating material layer 32, thereby improving the accuracy and reliability of the test results. During setting, the operator uses the adjustment key 27 to set a suitable pressure. The set pressure value is displayed on the digital display screen. The PLC controls the second motor to rotate the knob 24 to clamp or release the blade 23 based on the set pressure value, thus ensuring that the blade 23 receives the appropriate pressure for cutting the copper foil.

[0050] It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the scope of protection of this application. Therefore, the scope of protection of this patent application shall be determined by the appended claims.

Claims

1. A device for testing the peel strength of an insulation material from a copper foil, characterized by: The device includes a cutting fixture (10), a cutting blade (20), and a peel strength testing device. The cutting fixture (10) is provided with several test strip frames. The cutting blade (20) includes a housing (21) and a blade (23) installed in the housing (21). During cutting, the cutting fixture (10) is pressed onto a flexible copper foil substrate (30). The flexible copper foil substrate (30) includes an insulating material layer (32) and a copper foil layer (31) pressed onto the insulating material layer (32). The blade (23) adheres to the inner sidewall of the test strip frame and cuts the copper foil layer (31) on the flexible copper foil substrate (30) to obtain a copper foil test strip. The peel strength testing device is used to peel the copper foil test strip off the insulating material layer (32) to measure the peel strength between the copper foil layer (31) and the insulating material layer (32). The blade (23) is installed obliquely inside the housing (21), and the lower end of the blade (23) extends out of the housing (21). A roller (22) is installed on the housing (21). The roller (22) is connected to a first motor, and the first motor can drive the roller (22) to roll. The first motor is installed inside the housing (21). The blade (23) is adjustablely installed inside the housing (21) via a knob (24). The knob (24) is connected to a second motor, and the second motor can rotate the knob (24) to adjust the pressure of the blade (23). The second motor is electrically connected to a force sensor. When cutting the copper foil layer (31) with the blade (23), the blade (23) forms an angle of 30±5° with the lower surface of the box (21), and the cutting pressure of the blade (23) is set to 5-35g; During the cutting process, the blade (23) will not completely cut the copper foil layer (31). After cutting, it will be repeatedly bent at 90-180° along the cutting line of the copper foil layer (31) to completely break the copper foil layer (31) at the cutting line.

2. The testing device for the peel strength of insulating material to copper foil according to claim 1, characterized in that: The cutting fixture (10) is a square cutting fixture made of stainless steel. The cutting fixture (10) has a thickness of 2-5 mm, a length of 200-220 mm, and a width of 60-100 mm. The peel strength testing equipment is a universal testing machine.

3. The testing device for the peel strength of insulating material to copper foil according to claim 2, characterized in that: The test frame is a hollow structure formed on the cutting fixture (10), and the test frame is a rectangular structure. The test frame includes a first test frame (11) and a second test frame (12). The cutting fixture (10) is provided with a plurality of parallel first test frames (11) and a plurality of parallel second test frames (12). The width of the first test frame (11) is 2.5±0.5mm and the length is 160-200mm. The width of the second test frame (12) is 5±0.5mm and the length is 160-200mm.

4. The testing device for the peel strength of insulating material to copper foil according to claim 2, characterized in that: The spacing between two adjacent test frames is 5-10mm. The upper surface of the test frame is ground flat. The upper surface of the cutting fixture (10) has two parallel long sides (13) and two parallel short sides (14). The distance between the long side (13) and the nearest test frame is 5-10mm. The distance between the short side (14) and the nearest test frame is greater than or equal to 10mm.

5. The testing apparatus for the peel strength of insulating materials to copper foil according to claim 1, characterized in that: The flexible copper foil substrate (30) is a single-layer copper foil substrate or a double-layer copper foil substrate. When the flexible copper foil substrate (30) is a single-layer copper foil substrate, the flexible copper foil substrate (30) includes a copper foil layer (31) and an insulating material layer (32) that are pressed together, or the flexible copper foil substrate (30) includes a copper foil layer (31), an adhesive layer (33), and an insulating material layer (32) that are sequentially bonded together. When the flexible copper foil substrate (30) is a double-layer copper foil substrate, the flexible copper foil substrate (30) includes a copper foil layer (31), an insulating material layer (32), and a copper foil layer (31) that are sequentially bonded together, or the flexible copper foil substrate (30) includes a copper foil layer (31), an adhesive layer (33), an insulating material layer (32), an adhesive layer (33), and a copper foil layer (31) that are sequentially bonded together.

6. A method for testing the peel strength between an insulating material and copper foil, characterized in that: The testing using the testing apparatus according to any one of claims 1-5 specifically includes the following steps: Step 1: Place the cutting fixture (10) on the copper foil layer (31) of the soft copper foil substrate (30) to be cut, with the copper foil test strip exposed at the test strip frame on the cutting fixture (10); Step 2: Place the cutting tool (20) on the cutting fixture (10) and make the blade (23) fit against an inner sidewall of a test frame, with the lower end of the blade (23) inserted into the copper foil layer (31); Step 3: Start the cutting tool (20), the cutting tool (20) moves in a straight line along the flexible copper foil substrate (30), the blade (23) cuts the copper foil layer it passes through, and adjust the position of the cutting tool (20) so that the blade (23) cuts the copper foil test strip in the test strip frame in sequence. Step 4: Take out the cut flexible copper foil substrate (30) and bend it repeatedly at 90-180° along the cut line of the copper foil layer to completely break the cut line of the copper foil layer. At this time, the copper foil test strip of the same size as the test strip frame is separated from the main copper foil layer around its perimeter. Step 5: Use a peel strength tester to peel the copper foil test strip off the insulating material layer (32) to obtain the peel strength between the copper foil layer (31) and the insulating material layer (32).

7. The method for testing the peel strength between insulating material and copper foil according to claim 6, characterized in that: In step 3, before starting the cutting tool (20), the cutting pressure of the blade (23) is set to 5-35g. The cutting tool (20) moves backward along the soft copper foil substrate (30). After the copper foil test strip is cut open around its perimeter, the blade (23) is used to cut a diagonal line at any end of the copper foil test strip.

8. The method for testing the peel strength between insulating material and copper foil according to claim 7, characterized in that: The cutting pressure is determined according to the thickness of the copper foil layer (31). When the thickness of the copper foil layer is 9±1μm, the cutting pressure is set to 7±1g. When the thickness of the copper foil layer is 12±1μm, the cutting pressure is set to 10±1g. When the thickness of the copper foil layer is 18±1μm, the cutting pressure is set to 15±1g. When the thickness of the copper foil layer is 35±1μm, the cutting pressure is set to 30±1g.

Images