Copper clad laminate press glue flow detection device and glue flow detection method

Abstract

The present invention discloses a device for detecting glue flow during the pressing of copper clad laminates, which includes a support plate, a reference thermocouple and N glue flow thermocouples; the support plate is formed with a test hole; the N glue flow thermocouples are fixedly mounted on the support plate, the working end of each glue flow thermocouple is located at the test hole, and the cold end is located outside the support plate; when detecting glue flow during the pressing of copper clad laminates, a portion of the support plate is pressed between two adjacent semi-cured sheets at the edge of the stacked semi-cured sheets, and the test hole and the cold end of each glue flow thermocouple are located outside the stacked semi-cured sheets; the working end of the reference thermocouple is placed between two adjacent semi-cured sheets at the edge of the stacked semi-cured sheets, and the cold end is located outside the stacked semi-cured sheets and the support plate. The present invention also discloses a method for detecting glue flow during the pressing of copper clad laminates. The present invention can directly detect glue flow conditions online during the pressing process of the copper clad laminates without adding additional equipment, has no impact on the lamination process, is practical, simple and low in cost.

Description

Technical Field

[0001] The present invention relates to a copper clad laminate production technology, and in particular to a copper clad laminate press-bonding glue flow detection device and a glue flow detection method thereof. Background Art

[0002] Copper-clad laminate (CCL), also known as copper-clad laminate (CCL), is a prepreg made of a reinforcing material impregnated with resin and then baked at high temperature to form a solid. After slicing, one or more prepregs are laminated together, covered with copper foil on one or both sides, and then hot-pressed. It is primarily used in the manufacture of printed circuit boards (PCBs). Multiple PCBs and prepregs are pressed together to form a multilayer circuit board.

[0003] The resin in the prepreg is not highly cross-linked and will remelt during the hot pressing process. In a vacuum laminator, due to the vacuum and press pressure, the melted adhesive expel air from the interior during the lamination process. Simultaneously, the adhesive will flow out the edges of the prepreg. Therefore, the copper foil should be slightly larger than the prepreg. The resin continues to cross-link during the hot pressing process and eventually solidifies. This phenomenon of adhesive flowing out the edges of the prepreg during lamination is called glue bleed.

[0004] Glue flow is a normal phenomenon, but it should be avoided in excess. Excessive glue flow can cause voids to appear at the edges of a copper-clad laminate, known as glue deficiency. Excessive glue flow can also cause the thickness of the copper-clad laminate's edges to be significantly lower than the center, degrading its quality. Even more seriously, glue flow can flow onto the mirror-finished steel sheet, severely impacting production efficiency and product quality.

[0005] Controlling adhesive flow is a critical parameter during the lamination of copper-clad laminates, especially those with thicker thicknesses, and directly determines the quality of the lamination. Currently, copper-clad laminates are typically pressed using vacuum hot presses, which prevent direct observation of adhesive flow. Furthermore, the heating rate and timing of pressurization during the lamination process directly affect the extent of adhesive flow. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to be able to directly detect the glue flow condition online during the copper clad laminate pressing process without adding additional equipment, having no impact on the lamination process, being practical, simple and low-cost.

[0007] In order to solve the above technical problems, the present invention provides a copper clad laminate press-bonded adhesive flow detection device, which includes a support plate 3, a reference thermocouple 1 and N adhesive flow thermocouples 2, where N is a positive integer;

[0008] The support plate 3 is formed with a test hole 31;

[0009] The N glue-flow thermocouples 2 are fixedly mounted on the support plate 3 , with the working end of each glue-flow thermocouple 2 located at the test hole 31 and the cold end located outside the support plate 3 ;

[0010] When detecting the glue flow of the copper clad laminate, a portion of the support sheet 3 is pressed between two adjacent semi-cured sheets 4 at the edge of the stacked semi-cured sheets, and the test hole 31 and the cold ends of each glue flow thermocouple 2 are located outside the stacked semi-cured sheets; the working end of the reference thermocouple 1 is placed between two adjacent semi-cured sheets 4 at the edge of the stacked semi-cured sheets, and the cold end is located outside the stacked semi-cured sheets and the support sheet 3.

[0011] Preferably, the laminated prepregs are composed of at least 4 prepregs aligned and stacked together;

[0012] A portion of the support sheet 3 and the working end of the reference thermocouple 1 are pressed between two adjacent prepregs 4 in the middle of the edge of the stacked prepregs.

[0013] Preferably, the test hole 31 is rectangular;

[0014] When testing the adhesive flow of the copper clad laminate, the test hole 31 is located on the right side of the prepreg 4 , and the left side of the test hole 31 is parallel to the right side of the prepreg 4 .

[0015] Preferably, the distance from the left side of the test hole 31 to the right side of the prepreg 4 is greater than or equal to 0 and less than or equal to 1 mm.

[0016] Preferably, N is an integer greater than 1, and the distances from the working ends of the respective flow-glue thermocouples 2 to the left side of the test hole 31 are different from each other.

[0017] Preferably, N is an integer greater than 1, and the distance from the working end of each glue-flow thermocouple 2 to the left side of the test hole 31 decreases from front to back.

[0018] Preferably, N is an integer greater than 2, and the distance from the working end of each glue-flowing thermocouple 2 to the left side of the test hole 31 first decreases and then increases from front to back.

[0019] Preferably, when detecting the adhesive flow of the copper clad laminate, the working end of each adhesive flow thermocouple 2 is located between the copper foils covering the upper and lower sides of the laminated prepreg.

[0020] Preferably, the vertical outer diameter of the working end of the glue-flow thermocouple 2 is less than 0.7 mm.

[0021] Preferably, the distance between the working end of the glue-flow thermocouple 2 and the right side of the prepreg 4 is less than 10 mm.

[0022] In order to solve the above technical problems, the present invention provides a method for detecting glue flow of the copper clad laminate press glue flow detection device, comprising the following steps:

[0023] S1. The laminated prepreg and copper foil are placed between the hot pressing plates of a vacuum hot press, with the copper foil covering the upper and lower sides of the laminated prepreg;

[0024] Pressing a portion of the support sheet between two adjacent prepregs at the edge of the laminated prepregs, and positioning the test holes and the cold ends of the thermocouples at the outside of the prepregs;

[0025] The working end of the reference thermocouple is placed between two adjacent prepregs at the edge of the stacked prepregs, and the cold end is located outside the prepregs and the support sheet;

[0026] S2. Measure the distance from the working end of each thermocouple to the edge of the prepreg;

[0027] S3. Start the vacuum hot press to press the prepreg laminate and copper foil;

[0028] S4. Compare the temperatures detected by each glue flow thermocouple and the reference thermocouple. If the temperature detected by the reference thermocouple is greater than the first set value, and the difference between the temperature detected by a glue flow thermocouple and the temperature detected by the reference thermocouple 1 is less than the second set value, then the distance between the working end of the glue flow thermocouple and the edge of the semi-cured sheet is used as the glue flow amount at the glue flow thermocouple.

[0029] Preferably, in step S4, if the temperature detected by the reference thermocouple is greater than the first set value, when the difference between the temperature detected by a glue flow thermocouple and the temperature detected by the reference thermocouple is less than the second set value, this time is recorded as the glue flow start time.

[0030] Preferably, the first set value is 60°C and the second set value is 5°C.

[0031] Preferably, in step S1 , the depths of the support sheet and the reference thermocouple penetrating into the edges of two adjacent prepregs of the stacked prepregs are both less than 10 mm.

[0032] The copper clad laminate pressing glue flow detection device of the present invention can characterize the glue flow situation during the copper clad laminate pressing process by measuring the temperature difference through thermocouples. The glue flow situation can be directly detected online during the copper clad laminate pressing process without adding additional equipment and having no impact on the lamination process. The device is practical, simple and low-cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solution of the present invention, the following briefly introduces the drawings required for use in the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0034] Figure 1It is a structural schematic diagram of an embodiment of a device for detecting adhesive flow during pressing of copper clad laminates according to the present invention;

[0035] Figure 2 It is a schematic diagram of a method for detecting glue flow of a copper clad laminate pressing glue flow detection device of the present invention.

[0036] Description of the accompanying drawings:

[0037] 3 support sheets; 31 test holes; 1 reference thermocouple; 2 flow thermocouples; 4 prepregs. DETAILED DESCRIPTION

[0038] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without creative work are within the scope of protection of the present invention.

[0039] The terms "first", "second" and similar words used in this application do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprises" and similar words mean that the elements or objects preceding the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right", "front", "back" and the like are only used to indicate relative position relationships. When the absolute position of the object being described changes, the relative position relationship may also change accordingly.

[0040] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0041] Example 1

[0042] like Figure 1 As shown, the copper clad laminate press glue flow detection device includes a support plate 3, a reference thermocouple 1 and N glue flow thermocouples 2, where N is a positive integer;

[0043] The support plate 3 is formed with a test hole 31;

[0044] The N glue-flow thermocouples 2 are fixedly mounted on the support plate 3 , with the working end (also called the measuring end) of each glue-flow thermocouple 2 being located at the test hole 31 , and the cold end (also called the compensation end) being located outside the support plate 3 ;

[0045] When detecting the glue flow of the copper clad laminate, a portion of the support sheet 3 is pressed between two adjacent semi-cured sheets 4 at the edge of the stacked semi-cured sheets, and the test hole 31 and the cold ends of each glue flow thermocouple 2 are located outside the stacked semi-cured sheets; the working end of the reference thermocouple 1 is placed between two adjacent semi-cured sheets 4 at the edge of the stacked semi-cured sheets, and the cold end is located outside the stacked semi-cured sheets and the support sheet 3.

[0046] The copper-clad laminate press-bond adhesive flow detection device of Example 1 includes a support plate 3, a reference thermocouple 1, and an adhesive flow thermocouple 2. The adhesive flow thermocouple 2 is fixed to the support plate 3, which has a test hole 31. The working end of the adhesive flow thermocouple 2 is located in the area of ​​the test hole 31 and its position is fixed relative to the test hole 31. When using this copper-clad laminate press-bond adhesive flow detection device for testing, the support plate 3 is inserted and fixed between two adjacent prepregs 4 of the laminate, and the test hole 31 and the cold end of each adhesive flow thermocouple 2 are located outside the prepreg 4. The distance from the working end of each adhesive flow thermocouple 2 to the edge of the prepreg 4 is measured. During the copper clad laminate lamination process, the temperature measured by the glue-flow thermocouple 2 when there is no glue flow is the temperature of the current space. When the glue flows to the test hole 31 area and contacts the working end of the glue-flow thermocouple 2, the temperature measured by the glue-flow thermocouple 2 is the temperature of the glue flow. The working end of the reference thermocouple 1 near the support sheet 3 is directly inserted between two adjacent prepregs at the edge of the laminated prepreg to measure the temperature in the laminated prepreg. Figure 2 As shown, the temperatures detected by each glue flow thermocouple 2 and the reference thermocouple 1 are compared. When the temperature detected by a glue flow thermocouple 2 is significantly different from the temperature detected by the reference thermocouple 1, it indicates that the glue flow has not yet reached the working end of the glue flow thermocouple 2. When the temperatures detected by the two are close, the distance from the working end of the glue flow thermocouple 2 to the edge of the prepreg 4 can be used to represent the amount of glue flow.

[0047] The copper clad laminate pressing glue flow detection device of embodiment 1 can characterize the glue flow situation during the copper clad laminate pressing process by measuring the temperature difference through thermocouples. The cutting process after the copper clad laminate is pressed will cut off the reference thermocouple 1 and the support sheet 3 located at the edge of the stacked semi-cured sheet. The glue flow situation can be directly detected online during the copper clad laminate pressing process without adding additional equipment and having no impact on the lamination process. It is practical, simple and low-cost.

[0048] Example 2

[0049] Based on the copper clad laminate press flow detection device of embodiment 1, the stacked prepregs are composed of at least four prepregs aligned and stacked together;

[0050] A portion of the support sheet 3 and the working end of the reference thermocouple 1 are pressed between two adjacent prepregs 4 in the middle of the edge of the stacked prepregs.

[0051] Example 3

[0052] Based on the copper clad laminate press-bond adhesive flow detection device of embodiment 1, the test hole 31 is rectangular;

[0053] When testing the adhesive flow of the copper clad laminate, the test hole 31 is located on the right side of the prepreg 4 , and the left side of the test hole 31 is parallel to the right side of the prepreg 4 .

[0054] Preferably, the distance from the left side of the test hole 31 to the right side of the prepreg 4 is greater than or equal to 0 and less than or equal to 1 mm.

[0055] Preferably, N is an integer greater than 1, and the distances from the working ends of the respective flow-glue thermocouples 2 to the left side of the test hole 31 are different from each other.

[0056] Preferably, N is an integer greater than 1, and the distance from the working end of each glue-flow thermocouple 2 to the left side of the test hole 31 decreases from front to back.

[0057] Preferably, N is an integer greater than 2, and the distance from the working end of each glue-flowing thermocouple 2 to the left side of the test hole 31 first decreases and then increases from front to back.

[0058] Example 4

[0059] Based on the copper clad laminate press adhesive flow detection device of embodiment 3, when detecting the copper clad laminate press adhesive flow, the working end of each adhesive flow thermocouple 2 is located between the copper foils covering the upper and lower sides of the laminated prepregs.

[0060] Preferably, the vertical outer diameter of the working end of the glue-flow thermocouple 2 is less than 0.7 mm.

[0061] Preferably, the distance between the working end of the glue-flow thermocouple 2 and the right side of the prepreg 4 is less than 10 mm.

[0062] Example 5

[0063] The method for detecting adhesive flow of the copper clad laminate press adhesive flow detection device of the first to fourth embodiments includes the following steps:

[0064] S1. The laminated prepreg and copper foil are placed between the hot pressing plates of a vacuum hot press, with the copper foil covering the upper and lower sides of the laminated prepreg;

[0065] Press a portion of the support sheet 3 between two adjacent prepregs 4 at the edge of the laminated prepregs, and ensure that the test holes 31 and the cold ends of each thermocouple 2 are located outside the prepregs 4;

[0066] The working end of the reference thermocouple 1 is placed between two adjacent prepregs 4 at the edge of the stacked prepregs, and the cold end is located outside the prepreg 4 and the support sheet 3;

[0067] S2. Measure the distance from the working end of each flow thermocouple 2 to the edge of the prepreg 4;

[0068] S3. Start the vacuum hot press to press the prepreg laminate and copper foil;

[0069] S4. Figure 2 As shown, the temperatures detected by each glue flow thermocouple 2 and the reference thermocouple 1 are compared. If the temperature detected by the reference thermocouple 1 is greater than the first set value, and the difference between the temperature detected by a glue flow thermocouple 2 and the temperature detected by the reference thermocouple 1 is less than the second set value, the distance between the working end of the glue flow thermocouple 2 and the edge of the prepreg is used as the glue flow amount at the glue flow thermocouple 2.

[0070] Preferably, in step S4, if the temperature detected by the reference thermocouple 1 is greater than the first set value, when the temperature difference between the temperature detected by the glue flow thermocouple 2 and the temperature detected by the reference thermocouple 1 is less than the second set value, this time is recorded as the glue flow start time.

[0071] Preferably, the first set value is 60°C and the second set value is 5°C.

[0072] Preferably, in step S1 , the depth of the support sheet 3 and the reference thermocouple 1 penetrating into the edges of two adjacent prepregs 4 of the stacked prepregs is less than 10 mm.

[0073] The glue flow detection method of the copper clad laminate pressing glue flow detection device of Example 5 can directly judge the time and amount of glue flow online during the copper clad laminate pressing process, thereby guiding the copper clad laminate pressing process, without adding additional equipment, and has no impact on the lamination process. The method is simple.

[0074] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for detecting glue flow of a copper clad laminate press glue flow detection device, the copper clad laminate press glue flow detection device comprising a support plate (3), a reference thermocouple (1) and N glue flow thermocouples (2), where N is a positive integer; The support plate (3) is formed with a test hole (31); The N glue-flow thermocouples (2) are fixedly mounted on the support plate (3), the working end of each glue-flow thermocouple (2) is located at the test hole (31), and the cold end is located outside the support plate (3); When detecting the glue flow of the copper clad laminate, a portion of the support sheet (3) is pressed between two adjacent prepregs (4) at the edge of the stacked prepregs, and the test hole (31) and the cold ends of each glue flow thermocouple (2) are located outside the stacked prepregs; the working end of the reference thermocouple (1) is placed between the two adjacent prepregs (4) at the edge of the stacked prepregs, and the cold end is located outside the stacked prepregs and the support sheet (3); it is characterized in that The following steps are involved: S1. The laminated prepreg and copper foil are placed between the hot pressing plates of a vacuum hot press, with the copper foil covering the upper and lower sides of the laminated prepreg; Pressing a portion of the support sheet between two adjacent prepregs at the edge of the laminated prepregs, and positioning the test holes and the cold ends of the thermocouples at the outside of the prepregs; The working end of the reference thermocouple is placed between two adjacent prepregs at the edge of the stacked prepregs, and the cold end is located outside the prepregs and the support sheet; S2. Measure the distance from the working end of each thermocouple to the edge of the prepreg; S3. Start the vacuum hot press to press the prepreg laminate and copper foil; S4. Compare the temperatures detected by each glue-flowing thermocouple and the reference thermocouple. If the temperature detected by the reference thermocouple is greater than a first set value, and the difference between the temperature detected by a glue-flowing thermocouple and the temperature detected by the reference thermocouple (1) is less than a second set value, then the distance between the working end of the glue-flowing thermocouple and the edge of the semi-cured sheet is used as the glue flow amount at the glue-flowing thermocouple.

2. The method for detecting glue flow according to claim 1, wherein: In step S4, if the temperature detected by the reference thermocouple is greater than the first set value, when the difference between the temperature detected by a glue flow thermocouple and the temperature detected by the reference thermocouple is less than the second set value, this time is recorded as the glue flow start time.

3. The method for detecting glue flow according to claim 1, wherein: The first setting value is 60°C, and the second setting value is 5°C.

4. The method for detecting glue flow according to claim 1, wherein: In step S1 , the support sheet and the reference thermocouple are inserted into the edges of two adjacent prepregs of the stacked prepregs to a depth of less than 10 mm.

5. The method for detecting adhesive flow of a copper clad laminate press adhesive flow detection device according to claim 1, characterized in that: The laminated prepreg is composed of at least 4 prepregs aligned and stacked together; A portion of the support sheet (3) and the working end of the reference thermocouple (1) are pressed between two adjacent prepregs (4) in the middle of the edges of the stacked prepregs.

6. The method for detecting adhesive flow of a copper clad laminate press adhesive flow detection device according to claim 1, characterized in that: The testing hole (31) is rectangular; When detecting the adhesive flow of the copper clad laminate, the test hole (31) is located on the right side of the prepreg (4), and the left side of the test hole (31) is parallel to the right side of the prepreg (4).

7. The method for detecting adhesive flow of a copper clad laminate press adhesive flow detection device according to claim 6, characterized in that: The distance from the left side of the test hole (31) to the right side of the prepreg (4) is greater than or equal to 0 and less than or equal to 1 mm.

8. The method for detecting adhesive flow of a copper clad laminate press adhesive flow detection device according to claim 6, characterized in that: N is an integer greater than 1, and the distances from the working ends of the respective flow-glue thermocouples (2) to the left side of the test hole (31) are different from each other.

9. The method for detecting adhesive flow of a copper clad laminate press adhesive flow detection device according to claim 6, characterized in that: N is an integer greater than 1, and the distance from the working end of each glue-flowing thermocouple (2) to the left side of the test hole (31) decreases from front to back.

10. The method for detecting adhesive flow of a copper clad laminate press adhesive flow detection device according to claim 6, characterized in that: N is an integer greater than 2, and the distance from the working end of each glue-flowing thermocouple (2) to the left side of the test hole (31) first decreases and then increases from front to back.

11. The method for detecting adhesive flow of a copper clad laminate press adhesive flow detection device according to claim 1, characterized in that: When detecting the glue flow of the copper clad laminate, the working ends of the glue flow thermocouples (2) are located between the copper foils covering the upper and lower sides of the laminated prepreg.

12. The method for detecting adhesive flow of a copper clad laminate press adhesive flow detection device according to claim 11, characterized in that: The vertical outer diameter of the working end of the flow-glue thermocouple (2) is less than 0.7 mm.

13. The method for detecting adhesive flow of a copper clad laminate press adhesive flow detection device according to claim 11, characterized in that: The distance between the working end of the glue-flow thermocouple (2) and the right side of the prepreg (4) is less than 10 mm.

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