Rigid winding combination plate

Abstract

The invention provides a rigid-winding combined board. The rigid-winding combined board comprises a rigid board layer and flexible board layers which are located below the rigid board layer and sequentially arranged in a stacked mode. The hard board layer is provided with a slot, the soft board layer is provided with a slot, the width of the slot is smaller than that of the slot, the slots of the adjacent soft board layers are arranged in a staggered manner, and the slots of the soft board layers are gradually reduced from top to bottom in the height direction; the axes of the slots and the slots coincide in the projection direction, step parts are formed between the slots of the adjacent soft board layers, and the step parts protrude inwards relative to the upper soft board layer; the open seam is formed in the hard board layer, the size of the opening in the hard board layer is reduced, overflowing glue on the upper layer of the hard board layer is prevented from entering the open seam, the open grooves of the adjacent soft board layers are arranged in a staggered mode, the open grooves of the different soft board layers do not interfere with each other, and the situation that glue adhesion occurs between the adjacent soft board layers in the laser uncovering process is avoided; the overflowing glue flows on the surface of the step part by forming the step part to interfere the flowing of the overflowing glue, so that the flowing of the overflowing glue to the lower soft board layer is reduced.

Description

Technical Field

[0001] This invention relates to the field of printed circuit board technology, and in particular to a rigid-wound bonding board. Background Technology

[0002] Rigid-flex PCBs, also known as flexible PCBs, are composed of rigid PCBs and flexible PCBs selectively laminated together, resulting in a compact structure with conductive connections formed by metallized vias. Rigid-flex PCBs combine the regularity and toughness of conventional rigid PCBs with the flexibility and suppleness of flexible PCBs, allowing for movement, bending, folding, and twisting, and enabling three-dimensional wiring, thus significantly saving installation space for electronic components.

[0003] Opening the window and removing the cover is a core process in the production of rigid-flex PVC panels, such as... Figure 1 As shown, the existing windowing method involves pre-cutting a slit in the flexible area of ​​the flexible core board, making a window on the PP sheet at the corresponding position of the flexible area, and then pressing the rigid core board, PP and flexible core board together before opening the cover. This method will result in inconsistent stacking positions of multiple flexible core boards. After pressing, excess glue will fill the slit, making it difficult to open the cover.

[0004] Chinese patent application number 202010435286.1, published on September 18, 2020, discloses a method for preparing a rigid-flexible bonded plate with blind grooves. The method involves milling blind groove positions on the flexible plate, the rigid plate, and the prepreg; the rigid plate, prepreg, and flexible plate are stacked and pressed together in an alternating manner. The rigid-flexible bonded plate has blind grooves on the top rigid plate, and the dimensions of these blind grooves are larger than those on the lower prepreg and flexible plates. This allows the adhesive from the top layer to easily enter the bottom of the blind grooves during pressing. However, because adhesive overflows to both sides during pressing, this rigid-flexible bonded plate only uses the blind grooves in the flexible area to prevent adhesive overflow, resulting in a small amount of overflow that can flow into the blind grooves, affecting subsequent capping. Secondly, there is a significant height difference between the blind slot and non-blind slot positions in the rigid-flex plate, which can cause cracks in the rigid plate during lamination, leading to damage to the inner layer circuitry and affecting the sealing performance of the rigid-flex plate. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a rigid-wound bonding plate, wherein a slit is provided in the rigid plate layer, the width of the slit is smaller than the width of the slot, thereby reducing the size of the opening on the rigid plate layer and preventing excess adhesive from the upper layer of the rigid plate layer from entering the slit.

[0006] To solve the above-mentioned technical problems, the technical solution used in this invention is as follows:

[0007] The present invention discloses a rigid-wound composite plate, comprising a rigid plate layer and a flexible plate layer stacked sequentially below the rigid plate layer; the rigid plate layer has a slit, and the flexible plate layer has a slot, the width of the slit being smaller than the width of the slot, the slots of adjacent flexible plate layers being staggered, and the slots of the flexible plate layers gradually decreasing in size from top to bottom along the height direction; the axes of the slit and the slot coincide in the projection direction, and a step is formed between the slots of adjacent flexible plate layers, the step protruding inward relative to the upper flexible plate layer.

[0008] Preferably, the side spacing of the slots in adjacent flexible board layers is set at equal intervals.

[0009] Preferably, the side of the lower groove is spaced 100 μm from the side of the upper groove.

[0010] Preferably, a first PP layer is provided between the rigid board layer and the flexible board layer; and a second PP layer is provided on the surface of the rigid board layer away from the flexible board layer.

[0011] Preferably, a surface metal layer is provided on the surface of the second PP layer away from the rigid plate layer.

[0012] Preferably, the flexible board layer includes a flexible copper-clad laminate and a cover film; the cover film is disposed on the surface of the flexible copper-clad laminate.

[0013] Preferably, a pure adhesive layer is provided between adjacent flexible board layers.

[0014] Preferably, a recessed receiving groove is provided in the rigid area of ​​the flexible plate layer.

[0015] Preferably, the sum of the heights of the flexible regions of the multi-layer flexible board is H1, and the sum of the heights of the rigid regions of the multi-layer flexible board is H2; the height difference between H1 and H2 is in the range of 0-100μm.

[0016] Compared to existing technologies, the advantages of the rigid-wound bonding plate described in this invention are mainly reflected in the following aspects: Each flexible board layer has a slot, facilitating easy capping; slots are provided in the rigid board layer, reducing the opening size and preventing excess adhesive from the upper layer of the rigid board layer from entering the slots. The slots of adjacent flexible board layers are staggered, preventing interference between slots of different flexible board layers and avoiding adhesive adhesion between adjacent flexible board layers during laser capping; the axes of the slots and multiple slots coincide in the projection direction, achieving alignment between the slots and multiple slots. By forming a stepped portion that interferes with the flow of excess adhesive, when the rigid-wound bonding plate is pressed, the adhesive on the surface of the flexible board layer overflows and flows on the surface of the stepped portion, reducing the amount of excess adhesive flowing to the lower flexible board layers.

[0017] By setting equally spaced slots on the sides, it is convenient to pre-groove on the flexible board layer; this also facilitates the processing of the slots in each flexible board layer. A first PP layer and a second PP layer are used to bond the surface metal layer.

[0018] The invention utilizes a receiving groove to accommodate excess adhesive, further reducing its flow to the lower flexible board layer. Simultaneously, the receiving groove, in conjunction with the stepped portion, blocks excess adhesive flowing to both sides during the lamination of the flexible board layer, increasing the amount of adhesive blocked. This invention forms a stepped portion and a receiving groove to accommodate excess adhesive during the lamination of the rigid-wound bonded plate. When the rigid-wound bonded plate is laminated, some excess adhesive from both sides of the flexible board layer surface flows to the stepped portion, while some flows into the receiving groove. This significantly reduces the amount of adhesive blocked, preventing excess adhesive from directly entering the groove. Attached Figure Description

[0019] The above and other objects, features, and advantages of the invention will become clearer through a more detailed description of the preferred embodiments illustrated in the accompanying drawings. The same reference numerals denote the same parts throughout the drawings, and the drawings are not intentionally drawn to scale with actual dimensions; the focus is on illustrating the gist of the invention.

[0020] Figure 1 This is a schematic diagram of a rigid-flexible composite plate in the prior art.

[0021] Figure 2 This is a top view of the slit opening in the rigid plate layer in Embodiment 1 of the present invention.

[0022] Figure 3 This is a schematic diagram of the slotted stacked multilayer flexible board in Embodiment 1 of the present invention.

[0023] Figure 4 This is a schematic diagram of the rigid board layer and the flexible board layer stacked in Embodiment 1 of the present invention.

[0024] Figure 5 for Figure 4 A magnified view of A in the middle.

[0025] Figure 6 This is a schematic diagram illustrating the separation of the rigid board layer and the flexible board layer in Embodiment 1 of the present invention.

[0026] Figure 7 This is a schematic diagram of a flexible board layer in Embodiment 1 of the present invention.

[0027] Figure 8 This is a schematic diagram of a flexible board layer in Embodiment 2 of the present invention.

[0028] Figure 9 This is a schematic diagram illustrating the separation of the rigid board layer and the flexible board layer in Embodiment 2 of the present invention.

[0029] Reference numerals: Rigid layer 1, slot 10; Flexible layer 2, groove 20, step 21, rigid area 201, flexible area 202, receiving groove 22, flexible copper clad laminate 23, cover film 24; Pure adhesive layer 3; First PP layer 4; Second PP layer 5; Surface metal layer 6. Detailed Implementation

[0030] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand the present invention and implement it. However, the embodiments are not intended to limit the present invention. In this embodiment, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the present invention and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the present invention.

[0031] It should be noted that when one element is considered to be "connected" to another element, it can be directly connected to and integrated with the other element, or there may be an intervening element present. The terms "mounted," "one end," "the other end," and similar expressions used in this invention are for illustrative purposes only.

[0032] Example 1.

[0033] like Figure 2-7 As shown, a rigid-wound bonding board includes a rigid board layer 1 and a flexible board layer 2 stacked sequentially below the rigid board layer 1. The rigid board layer 1 has a slit 10, and the flexible board layer 2 has a groove 20. Each flexible board layer 2 has a groove 20, and the width of the slit is smaller than the width of the groove, which facilitates opening the cover. The slit 10 in the rigid board layer 1 reduces the size of the opening on the rigid board layer 1 and prevents excess glue from the upper layer of the rigid board layer 1 from entering the slit 10.

[0034] In a preferred embodiment, the rigid board layer 1 has two layers, with the top rigid board layer 1 disposed above the stacked flexible board layer 2 and the bottom rigid board layer 1 disposed below the stacked flexible board layer 2, and the slit 10 disposed in the top rigid board layer 1.

[0035] The slots 20 of adjacent flexible board layers 2 are staggered so that the slots 20 of different flexible board layers 2 will not interfere with each other; the slots 20 of the flexible board layers 2 gradually decrease in size from top to bottom along the height direction; the axis of the slit 10 and the slot 20 coincides in the projection direction, so that the slit 10 and the multiple slots 20 are aligned.

[0036] A step portion 21 is formed between the slots 20 of adjacent flexible board layers 2. The step portion 21 protrudes inward relative to the upper flexible board layer 2. By forming the step portion 21, the flow of excess adhesive is interfered. When the rigid bonding plate is pressed, the adhesive on the surface of the flexible board layer 2 will overflow. The excess adhesive flows on the surface of the step portion 21, reducing the amount of excess adhesive flowing to the lower flexible board layer.

[0037] The side spacing of the slots 20 in the adjacent flexible board layers 2 is equidistant. In a preferred embodiment, the side of the lower slot 20 is 100 μm apart from the side of the upper slot 20. By setting the slots 20 with equidistant side spacing, it is convenient to pre-cut the slots 20 on the flexible board layers 2; it is also convenient to process the slots 20 of each flexible board layer 2.

[0038] Reference Figure 1 As shown, the width D1 of the slit 10 is 20-100 μm; refer to Figure 2 As shown, the outermost slot 20 is the slot 20 corresponding to the top flexible board layer 2, and the width D2 of the top slot is 420-500μm; the middle slot 20 is the slot 20 corresponding to the flexible board layer 2 below the top flexible board layer 2, and the width D3 of the middle slot is 220-300μm; the innermost slot 20 is the slot 20 corresponding to the bottom flexible board layer 2, and the width D4w of the bottom slot is 20-100μm; each side of the lower slot is spaced 100μm from each side of the upper slot.

[0039] A pure adhesive layer 3 is provided between adjacent flexible board layers 2. In a preferred embodiment, the pure adhesive layer 3 is an AD adhesive layer. A first PP layer 4 is provided between the rigid board layer 1 and the flexible board layer 2; a second PP layer 5 is provided on the surface of the rigid board layer 1 away from the flexible board layer 2. A surface metal layer 6 is provided on the surface of the second PP layer 5 away from the rigid board layer 1. The first PP layer 4 and the second PP layer 5 are used to bond the surface metal layer 6.

[0040] The flexible board layer 2 includes a flexible copper-clad laminate 23 and a cover film 24; the cover film 24 is disposed on the surface of the flexible copper-clad laminate 23. In a preferred embodiment, the cover film 24 is a CVL cover film 24.

[0041] The rigid layer 1 is a double-sided CPRE board; preferably a glass fiber board.

[0042] In a preferred embodiment, in the top flexible board layer 2, the cover film 24 disposed near the rigid board layer 1 covers only the rigid area 201 of the flexible copper clad laminate 23, and the first PP layer 4 covers the flexible area 202 of the flexible copper clad laminate 23, and a groove 20 is provided on the first PP layer 4.

[0043] In a preferred embodiment, a pure adhesive layer 3 disposed near the bottom flexible board layer 2 covers the slot 20 of the adjacent flexible board layer 2, thereby preventing adhesive overflow into the flexible area 202 of the bottom flexible board layer 2. Since the pure adhesive layer 3 is an AD adhesive layer, it does not affect subsequent peeling.

[0044] In a preferred embodiment, the pure adhesive layer 3 located near the top flexible board layer 2 has a groove 20.

[0045] Example 2.

[0046] like Figure 8 , 9 As shown, a rigid-wound composite plate includes a rigid plate layer 1 and a flexible plate layer 2 stacked sequentially below the rigid plate layer 1; a recessed receiving groove 22 is provided in the rigid region 201 of the flexible plate layer 2. The receiving groove 22 is disposed on a covering film 24; the receiving groove 22 is formed by removing the covering film 24 corresponding to the rigid region 201 of the flexible plate layer 2. The remaining structure is the same as in Embodiment 1.

[0047] By forming the step portion 21 to interfere with the flow of excess adhesive, when the rigid bonding plate is pressed, the adhesive on the surface of the flexible board layer 2 will overflow. The excess adhesive flows on the surface of the step portion 21, reducing the amount of excess adhesive flowing to the lower flexible board layer. The receiving groove 24 is used to contain the excess adhesive, further reducing the amount of excess adhesive flowing to the lower flexible board layer 2; at the same time, the receiving groove 24 cooperates with the step portion 21 to block the excess adhesive flowing to both sides during the pressing of the flexible board layer, increasing the amount of excess adhesive blocked.

[0048] Because the flexible region 202 of the flexible layer 2 has slots, the height of the flexible region 202 is reduced, creating a height difference between the flexible region 202 and the rigid region 201. To prevent the height difference between the flexible region 202 and the rigid region 201 from being too large, which could cause cracks in the surface metal layer 6 during lamination, a receiving groove 22 is provided in the rigid region 201 of the flexible layer 2 to reduce the height of the rigid region 201 in the rigid-wound bonding plate and minimize the height difference between the flexible region 202 and the rigid region 201. Preferably, the depth of the multiple receiving grooves is adjusted according to the depth of the multiple slots.

[0049] In this embodiment, the slot 20 is provided through the flexible board layer 2 along the height direction of the flexible board layer 2, and the covering film 24 corresponding to the rigid area 201 of the flexible board layer 2 is completely removed to form the receiving slot 22.

[0050] In this embodiment, the sum of the heights of the flexible regions 202 of the multilayer flexible board layer 2 is set as H1, and the sum of the heights of the rigid regions 201 of the multilayer flexible board layer 2 is set as H2; the height difference between H1 and H2 is 0-100μm.

[0051] In this specification, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0052] In the description of this specification, the references to terms such as "preferred embodiment," "another embodiment," "other embodiment," or "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0053] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A rigid-wound bonding plate, characterized in that: It includes a rigid board layer and a flexible board layer stacked sequentially below the rigid board layer; the rigid board layer has a slit, and the flexible board layer has a slot, the width of the slit is smaller than the width of the slot, the slots of adjacent flexible board layers are staggered, and the slots of the flexible board layers gradually decrease in size from top to bottom along the height direction; the axes of the slit and the slot coincide in the projection direction, and a step is formed between the slots of adjacent flexible board layers, the step protruding inward relative to the upper flexible board layer.

2. The rigid-wound bonding plate according to claim 1, characterized in that: The side spacing of the slots in adjacent flexible board layers is set at equal intervals.

3. The rigid-wound bonding plate according to claim 2, characterized in that: The side of the lower groove is 100μm away from the side of the upper groove.

4. The rigid-wound bonding plate according to claim 1, characterized in that: A first PP layer is provided between the rigid board layer and the flexible board layer; a second PP layer is provided on the surface of the rigid board layer away from the flexible board layer.

5. The rigid-wound bonding plate according to claim 1, characterized in that: A surface metal layer is provided on the surface of the second PP layer away from the rigid board layer.

6. The rigid-wound bonding plate according to claim 1, characterized in that: The flexible board layer includes a flexible copper-clad laminate and a cover film; the cover film is disposed on the surface of the flexible copper-clad laminate.

7. The rigid-wound bonding plate according to claim 1, characterized in that: A pure adhesive layer is provided between adjacent flexible board layers.

8. The rigid-wound bonding plate according to claim 1, characterized in that: A recessed receiving groove is provided in the rigid area of ​​the flexible board layer.

9. The rigid-wound composite plate according to claim 8, characterized in that: The sum of the heights of the flexible regions of the multi-layer flexible board is H1, and the sum of the heights of the rigid regions of the multi-layer flexible board is H2; the height difference between H1 and H2 ranges from 0 to 100 μm.

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