A light strip made of a bowl-hole double-sided circuit board and a manufacturing method thereof

Abstract

The present invention relates to a lamp strip made of a double-sided circuit board with a bowl hole and a manufacturing method. Specifically, a single-sided copper-clad plate is etched to produce a front circuit, a solder resist is made, and then glue is applied on the back to form an intermediate glue layer. A mold is used to punch holes at places where bowl holes are required. Another single-sided circuit board is used as a back circuit. The back circuit board is aligned and attached to the glue-coated surface of the front circuit board with existing holes to produce a double-sided circuit board with a bowl hole. LED lamps are welded to the circuit board to produce a lamp strip of the double-sided circuit board with a bowl hole. The present invention is characterized in that the front solder resist layer, the front circuit layer and the intermediate insulating layer of part or all of the bowl holes are holes formed by pasting together, and the front circuit layer is not exposed when viewed from a top view, thereby solving the problems of poor appearance caused by the bowl hole not having multiple steps and poor soldering caused by chaotic tin flow during soldering.

Description

Technical Field

[0001] The invention relates to the field of circuit boards, and in particular to a light strip made of a bowl-hole double-sided circuit board and a manufacturing method thereof. Background Art

[0002] Usually, light strips are made with traditional double-sided circuit boards. The conduction of the double-sided circuit is generally achieved by drilling or punching through holes on the double-sided copper-clad board, and then using a copper electroplating process to form a conductive layer on the inner wall of the through hole on the double-sided circuit board to conduct electricity on the double-sided circuit. This causes serious pollution to the environment due to the need for electroplating.

[0003] The inventor has previously invented a series of patents for double-sided circuit boards with bowl holes, for example: Patent No.: 200920260552.0, Patent Name: Double-sided Circuit Board, Patent No.: 200920215983.5, Patent Name: Double-sided Circuit Board with Components, Patent No.: 201020514646.9, Patent Name: Double-sided Circuit Board Circuit Board and Combined Pads thereof, etc., all of which are made by processing holes at the positions where the double-sided circuit needs to be turned on before solder masking on the front single-sided board, and then making front solder masking, resulting in uneven front solder masking and the middle insulating layer at the hole wall, forming multiple steps between the front solder masking, the front copper, the middle insulating layer and the bottom of the bowl hole, resulting in poor appearance and inability to make high-end light strip products. At the same time, the front copper at the bowl hole is exposed when viewed from above, and when soldering, the copper at the bottom of the hole and the front copper expand due to the surface after the tin melts, resulting in chaotic tin flow, resulting in poor solder connection.

[0004] In order to overcome the above defects and shortcomings, the present invention covers the front copper with a front solder resist at the bowl hole, coats the back with glue, and then punches or drills holes at the same time, and then presses the back circuit together with the glue layer. The bowl-shaped bottom of the bowl hole is the back copper, and the front copper is not exposed from a top-down perspective, thereby solving the problem of poor appearance of multiple steps at the bowl hole and the poor soldering caused by the front circuit copper and the back circuit copper competing for tin during soldering. Summary of the invention

[0005] The present invention relates to a lamp strip made of a double-sided circuit board with a bowl hole and a manufacturing method. Specifically, a single-sided copper-clad plate is etched to produce a front circuit, a solder resist is made, and then glue is applied on the back to form an intermediate glue layer. A mold is used to punch holes at places where bowl holes are required. Another single-sided circuit board is used as a back circuit. The back circuit board is aligned and attached to the glue-coated surface of the front circuit board with existing holes to produce a double-sided circuit board with a bowl hole. LED lamps are welded to the circuit board to produce a lamp strip of the double-sided circuit board with a bowl hole. The present invention is characterized in that the front solder resist layer, the front circuit layer and the intermediate insulating layer of part or all of the bowl holes are holes formed by pasting together, and the front circuit layer is not exposed when viewed from a top view, thereby solving the problems of poor appearance caused by the bowl hole not having multiple steps and poor soldering caused by chaotic tin flow during soldering.

[0006] According to the present invention, a method for manufacturing a light strip made of a bowl-hole double-sided circuit board is provided. Specifically, after etching a single-sided copper-clad board to produce a front circuit, a front solder resist is made, and at the position where the bowl hole needs to be made, the solder resist layer is partially covered or completely covered, and then glue is applied to the back to form an intermediate glue layer, and holes are engraved with a laser, or holes are drilled with a drilling machine, or holes are punched with a mold. The holes simultaneously penetrate the front solder resist layer, the front circuit layer, the intermediate insulating layer and the intermediate glue layer. According to the design, another single-sided circuit board is manufactured as the back circuit, and the back circuit board is aligned and attached to the glue-coated surface of the front circuit board with a hole, with the metal of the back circuit facing the glue surface. After pressing, the intermediate glue layer overflows to the bottom of the bowl hole. The overflow is greater than 0mm and less than or equal to 0.8mm. The glue is cured by heating to make a bowl-hole double-sided circuit board. The LED lamp is soldered to the circuit board to make a light strip of the bowl-hole double-sided circuit board. At the position where the hole is located, the hole and the back circuit at the bottom of the hole form a bowl hole, and the back circuit exposed at the bottom of the bowl hole forms a bowl hole pad. The front solder mask layer and the middle insulating layer of part or all of the bowl holes are flush with the hole wall. The front circuit copper of part or all of the bowl holes is at the bowl hole and is not exposed from a top-down perspective. The back circuit metal is exposed at the bottom of the bowl hole when viewed from the front top-down perspective. The glue layer overflows on the metal at the bottom of the hole when viewed from the front top-down perspective. The overflow is greater than 0mm and less than or equal to 0.8mm.

[0007] According to the present invention, there is also provided a light strip made of a bowl-hole double-sided circuit board, comprising: a front solder resist layer; a front circuit layer; an intermediate insulating layer; an intermediate glue layer; a back circuit layer; a back insulating layer; a bowl hole; and components containing LEDs are welded on the front side; characterized in that the bottom of the bowl hole is the back circuit layer, and the front solder resist of part or all of the bowl holes covers the front circuit metal at the bowl hole, and when viewed from the front, the back circuit metal of the bowl bottom is exposed from the front to form a bowl hole solder pad, and the front circuit metal is not exposed at part or all of the bowl holes when viewed from the front. The front circuit layer metal is exposed or not exposed when viewed from the side of the hole wall, and there is an intermediate glue layer overflowing on the back circuit layer at the bottom of the bowl hole, and the overflow amount is greater than 0mm and less than or equal to 0.8mm, and the front solder resist layer and the intermediate insulating layer of part or all of the bowl holes are flush at the hole wall, and the LED is welded on the front circuit to form an LED light strip.

[0008] According to a preferred embodiment of the present invention, the light strip made of the bowl-hole double-sided circuit board is characterized in that, in the back circuit layer and the back insulating layer, at the position where the bowl hole is set, it is already recessed when viewed from the back of the circuit board, and when viewed from the front of the circuit board, the back circuit in the bowl hole has bulged upward, and the pads formed by the back circuit in the bowl hole are close to the same plane as the pads of the front circuit, and the pad surface on the front circuit is used as the reference plane of the plane, and the upper and lower ranges of the pad surface formed by the back circuit in the bowl hole and the reference plane are lower than the reference plane and not lower than 0.5 mm, and higher than the reference plane and not higher than 0.5 mm.

[0009] According to a preferred embodiment of the present invention, the light strip made of the bowl-hole double-sided circuit board is characterized in that the front solder resist layer is an ink solder resist layer or a cover film solder resist layer.

[0010] According to a preferred embodiment of the present invention, the light strip made of the bowl-hole double-sided circuit board is characterized in that the covering film solder resist layer is a PI film or a PET film.

[0011] According to a preferred embodiment of the present invention, the light strip made of the bowl-hole double-sided circuit board is characterized in that the bowl-hole pads are pads for welding components, pads for connecting boards, and pads for welding power lines.

[0012] According to a preferred embodiment of the present invention, the light strip made of the bowl-hole double-sided circuit board is characterized in that, on the soldering pad of the welding component provided with the bowl hole, part of the soldering feet of the component are soldered to the back circuit through the bowl hole, and the other part of the soldering feet are soldered to the front circuit, so that the front circuit and the back circuit are connected through the component.

[0013] According to a preferred embodiment of the present invention, the light strip made of the bowl-hole double-sided circuit board is characterized in that on the welding power line pad provided with the bowl hole, the power line is welded to the back circuit through the bowl hole.

[0014] According to a preferred embodiment of the present invention, the light strip made of the bowl-hole double-sided circuit board is characterized in that when multiple circuit boards are welded together on the connecting plate pad with the bowl holes, they are connected by welding to the back circuit through the bowl holes.

[0015] The details of one or more embodiments of the invention are set forth in the accompanying drawings and the detailed description below. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The features, objects and advantages of the present invention will become more apparent by reading this specification in conjunction with the following drawings, a brief description of which is as follows.

[0017] Figure 1This is a plan view of the front circuit after etching the single-sided flexible copper-clad laminate.

[0018] Figure 2 This is a plan view of the front circuit after printing the front solder mask.

[0019] Figure 3 This is a plan view of a single-sided circuit board after punching holes on the front circuit.

[0020] Figure 4 For Figure 3 ” Schematic diagram of the cross section at 1.3c.

[0021] Figure 5 This is a plan view of the back side circuit.

[0022] Figure 6 This is a plan view of a bowl-hole double-sided circuit board.

[0023] Figure 7 This is a cross-sectional diagram of a bowl-hole double-sided circuit board at the bowl hole 1.3c position.

[0024] Figure 8 This is a cross-sectional schematic diagram of a bowl-hole double-sided circuit board at the bowl hole 1.3a position.

[0025] Fig. 9 This is a schematic cross-sectional view of a bowl-hole double-sided circuit board at the bowl hole 1.3b position.

[0026] Fig.10 It is a cross-sectional schematic diagram showing that the back circuit layer and the back insulation layer bulge upward at the bowl hole 1.3c.

[0027] Fig.11 This is a plan view of the bare light strip after the SMT patch is soldered to the LED light. DETAILED DESCRIPTION

[0028] The present invention will be described in detail below by taking preferred embodiments as examples.

[0029] However, those skilled in the art should understand that the following descriptions are merely examples and descriptions of some preferred embodiments and do not impose any limitations on the claims of the present invention.

[0030] 1. Production of bowl hole double-sided circuit board

[0031] Using the traditional circuit board manufacturing process, the single-sided flexible copper clad board is made into a front circuit 1 (such as Figure 1 As shown), the solder mask 2 is printed on the front circuit 1, exposing the solder pads 1.2 for soldering components and the solder pads 1.1 for soldering power lines, and then the characters are printed on the screen to make a single-sided circuit board (as shown). Figure 2 As shown), then glue is applied on the back of the single-sided circuit board, that is, the middle insulating layer 3, to form the middle glue layer 4, and then holes 1.3a, 1.3b and 1.3c are punched out at the positions where the bowl holes need to be set in the double-layer circuit using the designed mold on the punching machine, and the holes penetrate the front solder mask 2, the front circuit 1, the middle insulating layer 3 and the middle glue layer 4 (as shown). Figure 3 , Figure 4 shown).

[0032] The conventional circuit board manufacturing process is used to make a single-sided flexible copper-clad board through the processes of screen printing circuit anti-corrosion ink, baking and curing, etching, and film stripping to produce a back circuit 5 (such as Figure 5 (shown)

[0033] The metal surface of the back circuit 5 is aligned and attached to the middle glue layer 4 of the punched single-sided circuit board, and pressed together to form bowl holes at holes 1.3a, 1.3b and 1.3c. The bottom of the bowl hole is the back circuit 5. Looking down at the bottom of the bowl from the front, the metal of the back circuit is exposed from the front. At the bottom of the bowl hole, the glue overflowed from the middle glue layer 4 due to pressing is on the back circuit 5, and the overflow amount is greater than 0 to 0.8 mm (such as Figure 6 , Figure 7 , Figure 8 , Fig. 9 shown).

[0034] At the bowl hole 1.3c, from the cross-section, the hole wall is the front solder mask 2, the front circuit 1, the middle insulating layer 3 and the middle glue layer 4, and the front solder mask 2 is flush with the front circuit 1 and the middle insulating layer 3 at the hole wall (such as Figure 7 shown).

[0035] At the bowl hole 1.3a, from the cross-section, the hole wall is the front circuit 1, the middle insulating layer 3 and the middle rubber layer 4, and the front circuit 1 and the middle insulating layer 3 are flush at the hole wall (such as Figure 8 shown).

[0036] At the bowl hole 1.3b, from the cross-section, the hole wall is the front solder resist 2, the middle insulating layer 3 and the middle glue layer 4, and the front solder resist 2 and the middle insulating layer 3 are flush at the hole wall (such as Fig. 9 shown).

[0037] Then, it is baked and cured, OSP anti-oxidation surface treated, formed and FQC processed to make a bowl hole double-sided circuit board (such as Figure 6 , Figure 7 , Figure 8 , Fig. 9 shown).

[0038] like Fig.10As shown, the back circuit 5 and the back insulating layer 6 protrude toward the front circuit 1 at the position of the bowl hole 1.3c, and the back circuit 5 in the bowl hole 1.3c forms a soldering pad, with the soldering pad surface on the front circuit as the reference plane of the plane, that is, the position of the reference line 7.1. The upper and lower ranges of the soldering pad surface formed by the back circuit in the bowl hole and the reference plane are: downwardly lower than the reference plane, not lower than the reference plane by 0.5mm, that is, the position of the reference line 7.3, and upwardly higher than the reference plane, not higher than the reference plane by 0.5mm, that is, the position of the reference line 7.2.

[0039] 2. SMT patch

[0040] Using the traditional SMT patch process, on the solder paste printer, use a steel mesh to print the solder paste on the component pads 1.2 of the circuit board, then mount the LED lamp beads 8 and the resistor 9 on the solder paste printed pads 1.2, and then solder the EED lamp beads 8 and the resistor 9 to the circuit board through reflow soldering to make a bowl hole double-sided circuit board LED light strip (such as Fig.11 shown).

[0041] The present invention applies glue to the back side after the front side solder resist is applied to cover the front side copper at the bowl hole, and then punches or drills holes at the same time, and then the back side circuit is glued and pressed together through the glue layer, so that the bowl-shaped bottom of the bowl hole is the back side copper, and the front side copper is not exposed when viewed from a top view, thereby solving the problem of poor appearance of multiple steps at the bowl hole and poor soldering caused by the front side circuit copper and the back side circuit copper competing for tin during soldering.

[0042] The present invention is described in detail above by combining the accompanying drawings with a specific embodiment of a light strip made of a bowl-hole double-sided circuit board and a manufacturing method. However, those skilled in the art should understand that the above description is only an example to illustrate and describe some specific implementation methods, and does not limit the scope of the present invention, especially the scope of the claims.

Claims

1. A method for manufacturing a light strip made of a bowl-hole double-sided circuit board. Specifically, after etching a single-sided copper-clad board to make a front circuit, a front solder mask is made. At the position where the bowl hole needs to be made, a solder mask layer is partially covered or completely covered. Then, glue is applied to the back to form an intermediate glue layer. Holes are engraved with a laser, or holes are drilled with a drilling machine, or holes are punched with a mold. The holes simultaneously penetrate the front solder mask layer, the front circuit layer, the intermediate insulating layer and the intermediate glue layer. According to the design, another single-sided circuit board is made as the back circuit. The back circuit board is aligned and attached to the glue-coated surface of the front circuit board with a hole, with the metal of the back circuit facing the glue surface. After pressing, the intermediate glue layer overflows to the bottom of the bowl hole, and the overflow The amount is greater than 0mm and less than or equal to 0.8mm. The glue is cured by heating to make a bowl-hole double-sided circuit board. The LED lamp is welded to the circuit board to make a light strip of the bowl-hole double-sided circuit board. At the position where the hole is located, the hole and the back circuit at the bottom of the hole form a bowl hole, and the back circuit exposed at the bottom of the bowl hole forms a bowl hole pad. The front solder mask layer and the middle insulating layer of part or all of the bowl holes are flush with the hole wall. The front circuit copper of part or all of the bowl holes is at the bowl hole and is not exposed when viewed from a top-down perspective. The back circuit metal is exposed at the bottom of the bowl hole when viewed from a front top-down perspective. The glue layer overflows on the metal at the bottom of the hole when viewed from a front top-down perspective. The overflow amount is greater than 0mm and less than or equal to 0.8mm.

2. A light strip made of a bowl-hole double-sided circuit board, comprising: Front solder mask; Front circuit layer; Intermediate insulation layer; Middle glue layer; Back circuit layer; Back insulation layer; Bowl hole; Solder the components including LED on the front side; It is characterized in that the bottom of the bowl hole is the back circuit layer, the front solder resist of part or all of the bowl holes covers the front circuit metal at the bowl hole, and the back circuit metal is exposed from the front of the bottom of the bowl when viewed from the front to form a bowl hole solder pad, and the front circuit metal is not exposed at part or all of the bowl holes when viewed from the front, and the front circuit layer metal is exposed or not exposed when viewed from the side of the hole wall. There is an intermediate glue layer overflowing on the back circuit layer at the bottom of the bowl hole, and the overflow amount is greater than 0mm and less than or equal to 0.8mm. The front solder resist layer and the intermediate insulating layer of part or all of the bowl holes are flush at the hole wall, and the LED is welded on the front circuit to form an LED light strip.

3. The light strip made of a bowl-hole double-sided circuit board according to claim 2, characterized in that: In the back circuit layer and the back insulating layer, at the position where the bowl hole is set, it is already sunken when viewed from the back of the circuit board, and when viewed from the front of the circuit board, the back circuit in the bowl hole has bulged upward, and the pads formed by the back circuit in the bowl hole are close to the same plane as the pads of the front circuit, and the pad surface on the front circuit is used as the reference plane of the plane. The upper and lower ranges of the pad surface formed by the back circuit in the bowl hole and the reference plane are lower than the reference plane and not lower than 0.5 mm, and higher than the reference plane and not higher than 0.5 mm.

4. The light strip made of a bowl-hole double-sided circuit board according to claim 1 or 2, characterized in that: The front solder resist layer is an ink solder resist layer or a cover film solder resist layer.

5. The light strip made of a bowl-hole double-sided circuit board according to claim 4, characterized in that: The cover film solder resist layer is a PI film or a PET film.

6. The light strip made of a bowl-hole double-sided circuit board according to claim 1 or 2, characterized in that: The bowl hole pad is a pad for welding components, a pad for connecting a board, or a pad for welding a power line.

7. The light strip made of a bowl-hole double-sided circuit board according to claim 6, characterized in that: On the soldering pad of a soldering component provided with a bowl hole, part of the soldering feet of the component are soldered to the back circuit through the bowl hole, and the other part of the soldering feet are soldered to the front circuit, so that the front circuit and the back circuit are connected through the component.

8. The light strip made of a bowl-hole double-sided circuit board according to claim 6, characterized in that: On the welding power line pad provided with a bowl hole, the power line is welded to the rear circuit through the bowl hole.

9. The light strip made of a bowl-hole double-sided circuit board according to claim 6, characterized in that: When a plurality of circuit boards are welded and connected to each other on a connecting plate pad provided with a bowl hole, they are welded to the back circuit through the bowl hole for connection.

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