Local exposure-free device of PCB (printed circuit board)

Abstract

The utility model relates to the technical field of PCB circuit boards, and provides a local non-exposure device of a PCB circuit board, comprising: a shading mechanism, the shading mechanism comprising a film, the film comprising a light blocking area, the light blocking area being capable of blocking a local part of the PCB circuit board and forming a non-exposure area; the partition light source emits light rays to the PCB, the partition light source can control local opening and closing of the light-emitting face, and the area, not irradiated by the light rays, of the PCB forms a non-exposed area; wherein the non-exposed area formed by the shading mechanism and the non-exposed area formed by the partition light source coincide with each other, the vertical distance from the shading mechanism to the PCB is smaller than the vertical distance from the partition light source to the PCB, and the shading mechanism and the partition light source selectively work. Due to the fact that the non-exposed area is arranged, the dry film fragments cannot be irradiated by light, the non-cured dry film fragments can be easily dissolved by the developing solution even if the dry film fragments fly to other pattern positions, and the PCB cannot be bad.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of circuit board manufacturing, and particularly relates to a partial non-exposed light device for PCB circuit board. BACKGROUND

[0002] In the production process of a PCB circuit board, the irradiation of ultraviolet light is needed to make some areas of dry film solidify so as to be developed and remove the un-solidified dry film, and then form a circuit, which is called exposure.

[0003] As shown in the figure, Figure 1 The exposure irradiation principle in the processing of a PCB circuit board is shown, light 1 will be screened by a light shielding piece 5 on the irradiation path, only part of the light 1 is allowed to pass through, and the passing light 1 will act on the dry film 4, and the copper layer and the substrate 6 are below the dry film 4, and the copper layer can also be divided into a processed copper layer 2 and an unprocessed copper layer 3.

[0004] In the processing of a PCB circuit board, mechanical rolling will be experienced, thereby producing dry film fragments, if the dry film fragments are not irradiated by light, they will be easily dissolved in development, and will not have a negative impact in the subsequent process. If some dry film fragments are irradiated by light, they are not easy to be dissolved, and the parts below the dry film fragments that should be dissolved cannot be eroded by the developing solution, thereby possibly causing a defective phenomenon of the PCB circuit board product. CONTENT OF THE INVENTION

[0005] The present application is made in view of the above-mentioned prior art. The purpose of the present application is to provide a partial non-exposed light device for a PCB circuit board.

[0006] The technical solution adopted by the present application comprises: a light shielding mechanism, the light shielding mechanism comprises a film, the film comprises a light blocking area, the light blocking area can shield part of a PCB circuit board and form a non-exposed light area; a partitioned light source, the partitioned light source emits light to the PCB circuit board, the partitioned light source can control the opening and closing of part of the light emitting surface, and the area of the PCB circuit board that is not irradiated by the light forms the non-exposed light area; wherein the non-exposed light area formed by the light shielding mechanism and the non-exposed light area formed by the partitioned light source overlap with each other, the vertical distance from the light shielding mechanism to the PCB circuit board is less than the vertical distance from the partitioned light source to the PCB circuit board, and the light shielding mechanism and the partitioned light source selectively work.

[0007] As a further improvement of the present application, the film is divided into a light blocking area and a light transmitting area, the light blocking area can prevent the light from passing through, and the light transmitting area allows the light to pass through.

[0008] As a further improvement of the present application, the light-emitting state of the partitioned light source is divided into a light-off area and a light-emitting area, the position of which can be dynamically changed, the light-off area does not emit light, and the light-emitting area emits ultraviolet light.

[0009] As a further improvement of the present application, the PCB circuit board edge has an exposed edge that is not covered by the dry film, and one or more of the plurality of light-exposed areas is an edge light-exposed area that overlaps with the exposed edge.

[0010] As a further improvement of the present application, the width of the light-exposed area is greater than the width of the exposed edge.

[0011] As a further improvement of the present application, the edge light-exposed area is independently two, the profile of the two independent edge light-exposed areas is rectangular, and the two edge light-exposed areas are symmetrically arranged on both sides of the PCB circuit board.

[0012] As a further improvement of the present application, the partitioned light source is connected with an electric control module, the electric control module controls the position change of the light-off area and the light-emitting area; and the light shielding mechanism includes an electric actuator that drives the film to change the position relative to the PCB circuit board.

[0013] As a further improvement of the present application, the light-blocking area is a black light-resistant carbon-based ink area of the film.

[0014] As a further improvement of the present application, the partitioned light source is a UV LED surface light source, which includes a plurality of arrayed independent light areas, each of which has a square profile with a side length not greater than 100 μm.

[0015] The PCB circuit board of the present application has the following advantages:

[0016] By increasing the light-exposed area, that is, locally modifying the entire exposure area, the dry film is not in contact with light and does not react with light, so it will not be cured. Dry film fragments are often caused by mechanical twisting action in the production process of PCB circuit board. If the light-exposed area is not specially set, the dry film fragments will be cured by light and will not be dissolved in the developer. If the dry film fragments fly to other positions of the PCB circuit board, such as covering a certain key position, it will hinder the developer from entering this position, thereby causing product defects. Because the light-exposed area is set, the dry film fragments will not be irradiated by light, and the uncured dry film fragments will be easily dissolved in the developer even if they fly to other pattern positions, and will not cause defects in the PCB circuit board.

[0017] The unexposed area can be generated in two ways, one is the light blocking area of the film, which is physical shielding, and there is no requirement for the control of the light source. The other is to let the sub-area light source some local light and some local not light, the part not illuminated by light, the dry film also will not be cured. The results of the two ways are basically the same.

[0018] The two ways can be used independently or in combination, which increases the flexibility of operation.

[0019] Because the light shielding mechanism and the sub-area light source can be selectively operated, it can adapt to different types of PCB circuit boards and different processing needs, and has strong adaptability. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments, the drawings of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application, and other drawings can also be obtained according to these drawings without creative labor for those skilled in the art.

[0021] Figure 1 is a schematic diagram of an embodiment of the exposure irradiation of the PCB circuit board;

[0022] Figure 2 is a schematic diagram of a first embodiment of the local unexposed device of the PCB circuit board of the present application;

[0023] Figure 3 is a schematic diagram of a second embodiment of the local unexposed device of the PCB circuit board of the present application;

[0024] Figure 4 is a schematic diagram of an embodiment of the PCB circuit board;

[0025] Figure 5 is a schematic diagram of the PCB circuit board of an embodiment of the local unexposed device of the PCB circuit board of the present application;

[0026] Figure 6 is a schematic diagram of the effect change of the PCB circuit board of an embodiment of the local unexposed device of the PCB circuit board of the present application.

[0027] BRIEF DESCRIPTION OF DRAWINGS

[0028] 1 - light; 2 - treated copper layer; 3 - untreated copper layer; 4 - dry film; 5 - light shielding device; 6 - substrate; 7 - PCB circuit board; 701 - exposed edge; 8 - exposed area; 9 - unexposed area; 10 - dry film fragment; 11 - partition light source; 1101 - light-off area; 1102 - light-on area; 12 - film; 1201 - light-blocking area; 1202 - light-transmitting area; L1 - exposed width. DETAILED DESCRIPTION

[0029] The exemplary embodiments of the present application will be described hereinafter with reference to the accompanying drawings. It is to be understood that the specific description is only for the purpose of teaching the skilled in the art how to implement the present application, and is not intended to exhaust all possible ways of the present application, nor to limit the scope of the present application.

[0030] Reference Figure 2 , Figure 3 The embodiments of the present application provide a device for locally unexposing a PCB circuit board. The device comprises a light shielding mechanism and a partition light source 11. As shown in Figure 2 , the light shielding mechanism comprises a film 12, and the film 12 comprises a light-blocking area 1201, which can shield a part of the PCB circuit board 7 and form an unexposed area 9. As shown in Figure 3 , the partition light source 11 emits light 1 to the PCB circuit board 7, and the partition light source 11 can control the local closing of the light-emitting surface, the locally closed light-emitting surface does not emit light 1, and the area of the PCB circuit board 7 not irradiated by the light 1 also forms an unexposed area 9. The unexposed area 9 formed by the light shielding mechanism and the unexposed area 9 formed by the partition light source 11 coincide with each other. The distance from the light shielding mechanism to the PCB circuit board 7 is less than the distance from the partition light source 11 to the PCB circuit board 7. The light shielding mechanism and the partition light source 11 selectively operate according to the needs of the production of the PCB circuit board 7, that is, the light shielding mechanism can be used to form the unexposed area 9, or the partition light source 11 can be used to form the unexposed area 9. The two are used alternatively to form the unexposed area 9, or even the two are used simultaneously to form the unexposed area 9.

[0031] In an embodiment, as shown in Figure 2 , the film 12 is divided into a light-blocking area 1201 and a light-transmitting area 1202, the light-blocking area 1201 can prevent the light 1 from passing through, and the light-transmitting area 1202 can allow the light 1 to pass through.

[0032] In an embodiment, as shown in Figure 3 , according to the light-emitting state of the partition light source 11, the partition light source 11 is divided into a light-off area 1101 and a light-on area 1102, the light-off area 1101 does not emit light, and the light-on area 1102 emits ultraviolet light. Figure 3 Compared with Figure 2 , Figure 3The arrows used to indicate the light rays 1 are fewer.

[0033] There are two ways to form the unexposed area 9, one is physical shielding, that is, a patterned film 12 can be used to block part of the light 1 from passing through and acting on the dry film 4. The other is to control the local on-off of the partition light source 11, and the local partition light source 11 that is turned off will not emit ultraviolet light. From the result point of view, it plays almost the same role as physical shielding.

[0034] In an embodiment, as shown in Figure 4 , Figure 5 The PCB circuit board 7 has an exposed edge 701 that is not covered by the dry film 4, and one or more of the plurality of unexposed areas 9 overlap with the exposed edge 701 to form an edge unexposed area.

[0035] The beneficial effects of the above embodiment are that the film 12 providing the unexposed area 9 has a large enough area to facilitate full adhesion to the PCB circuit board 7, and the area of the edge of the PCB circuit board 7 is also utilized.

[0036] In an embodiment, as shown in Figure 5 The width of the unexposed area 9 is greater than the width of the exposed edge 701.

[0037] The beneficial effects of the above embodiment are that the unexposed area 9 has a relatively large area, which ensures complete coverage of the specified parts.

[0038] In an embodiment, as shown in Figure 5 The edge unexposed area is independent of two, the profiles of the two independent edge unexposed areas are rectangular, and the two edge unexposed areas are symmetrically arranged on both sides of the PCB circuit board 7. The width of the exposed edge 701 is the exposed width L1, and the width of the unexposed area 9 is greater than the exposed width L1.

[0039] The beneficial effects of the above embodiment are that the dry film 4 will form dry film fragments 10 after breaking, and the areas on the PCB circuit board 7 that are easily affected by the dry film fragments 10 are set as unexposed areas 9, thereby greatly reducing the negative effects of the dry film fragments 10 on the entire PCB circuit board 7.

[0040] As shown in Figure 6 , Figure 6 The upper half of Figure 6 The lower half of Figure 6The change from the upper half to the lower half essentially alters the area exposed to light. Thus, even if the dry film 4 is damaged by external force, the dry film fragments 10 in the unexposed area 9 are not exposed to light and can still dissolve in the developer, eliminating the negative impacts of subsequently cured dry film fragments 10.

[0041] Figure 4 and Figure 5 In order to make it easier to distinguish, two different textures are used to fill the same position on the PCB circuit board 7 to distinguish the exposed area 8 and the non-exposed area 9. Figure 4 The final effect is as follows Figure 6 As shown in the upper part, Figure 5 The final effect is as follows Figure 6 As shown in the lower half, it can achieve a zero-defect effect.

[0042] In one embodiment, the partitioned light source 11 is signal-connected to an electronic control module, which controls the positional changes of the light-blocking area 1101 and the light-emitting area 1102. The light-blocking mechanism includes an electric actuator that drives the film 12 to change its relative position with the PCB circuit board 7.

[0043] The beneficial effects of using the above embodiments are: the electronic control module can improve the degree of freedom in changing the light-emitting and dark (non-light-emitting) areas of the zoned light source 11; and the electric actuator improves the efficiency of the film film 12 position transfer and attachment, thereby enhancing the level of automation.

[0044] In one embodiment, the light-blocking area 1201 is a black anti-light carbon-based ink area on the surface of the film 12.

[0045] The beneficial effects of using the above embodiments are: black carbon-based ink can effectively block ultraviolet rays and prevent light from penetrating during exposure, thereby ensuring accurate pattern transfer. The high light-blocking properties of black anti-light carbon-based ink can reduce light scattering, improve imaging accuracy, make the imaging edges sharper, reduce jaggedness and blurring, and thus ensure clear boundaries of the unexposed light area 9.

[0046] In one embodiment, the partitioned light source 11 is a UVLED surface light source, which includes several independent light zones arranged in an array, and the outline of each independent light zone is a square with a side length of no more than 100 μm.

[0047] The beneficial effects of the above-mentioned embodiments are that the UV LED light source can quickly emit high-intensity ultraviolet light, significantly shorten the curing time, and improve the production efficiency. And it can be turned on and off instantly, without the need for preheating or cooling, improving the operation flexibility, suitable for dynamic changes of the light-off area 1101 and the light-emitting area 1102. At the same time, each independent light area is small enough, so the changes and combinations of the light-off area 1101 and the light-emitting area 1102 are rich, and the boundary of the exposed light area 9 can be accurately formed.

[0048] The above-mentioned embodiments are only for illustrating the technical concept and characteristics of the present application, and the purpose is to enable those skilled in the art to understand the content of the present application and implement it, and cannot limit the protection scope of the present application. Any equivalent changes or modifications made according to the spirit and essence of the present application should be covered within the protection scope of the present application.

Claims

1. A device for partially concealing light on a PCB circuit board, characterized in that, include: A light-blocking mechanism, comprising a film, the film including a light-blocking area, the light-blocking area being able to partially block a portion of the PCB circuit board and form a light-free area; A partitioned light source emits light onto the PCB circuit board. The partitioned light source can control the partial opening and closing of the light-emitting surface. The areas of the PCB circuit board that are not illuminated by the light form the light-unexposed areas. The light-shielding area formed by the light-shielding mechanism coincides with the light-shielding area formed by the partitioned light source. The vertical distance from the light-shielding mechanism to the PCB circuit board is less than the vertical distance from the partitioned light source to the PCB circuit board. The light-shielding mechanism and the partitioned light source operate selectively.

2. The PCB circuit board partial light-exposing device according to claim 1, characterized in that: The film is divided into a light-blocking area and a light-transmitting area. The light-blocking area can prevent light from passing through, while the light-transmitting area allows light to pass through.

3. The partial light-exposed device for a PCB circuit board according to claim 1, characterized in that: According to the light emission state of the partitioned light source, the partitioned light source is divided into a closed light zone and a light emission zone whose positions can be dynamically changed. The closed light zone does not emit light, and the light emission zone emits ultraviolet light.

4. The partial light-exposed device for a PCB circuit board according to claim 1, characterized in that: The PCB circuit board has an exposed edge that is not covered by dry film, and one or more of the non-exposed light areas are edge non-exposed light areas that overlap with the exposed edge.

5. The PCB circuit board partial light-exposing device according to claim 4, characterized in that: The width of the non-light-exposed area is greater than the width of the exposed edge.

6. The partial light-exposed device for a PCB circuit board according to claim 4, characterized in that: The two non-light-exposed edge areas are independent, and the outlines of these two independent non-light-exposed edge areas are both rectangular. These two non-light-exposed edge areas are symmetrically arranged on both sides of the PCB circuit board.

7. The partial light-exposed device for a PCB circuit board according to claim 3, characterized in that: The partitioned light source is connected to an electronic control module, which controls the position changes of the closed light area and the light-emitting area. The light-shielding mechanism includes an electric actuator that drives the film to change its relative position with the PCB circuit board.

8. The partial light-exposed device for a PCB circuit board according to claim 2, characterized in that: The light-blocking area is the black anti-light carbon-based ink area of ​​the film.

9. The partial light-exposed device for a PCB circuit board according to claim 3, characterized in that: The partitioned light source is a UVLED surface light source, which includes several independent light zones arranged in an array. The outline of each independent light zone is a square with a side length of no more than 100μm.

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