阅读说明：本技术 一种提高线路板丝印阻焊效率的方法 (Method for improving solder mask printing efficiency of circuit board ) 是由 寻瑞平 戴勇 杨勇 汪广明 于 2019-08-26 设计创作，主要内容包括：本发明涉及印制电路板技术领域,具体为一种提高线路板丝印阻焊效率的方法。本发明通过在PCB生产板的第二表面丝印阻焊油墨时配合使用设置有支撑块的丝印辅助板,在第一表面上丝印阻焊油墨后即可马上在第二表面进行丝印,无需静置等待第一表面上的阻焊油墨干燥以及预烤后再进行第二表面的丝印,不仅可节省第一次静置和预烤的时间,提高生产效率,还可避免第二表面上的铜面裸露在湿暖的空气中导致氧化而引入品质隐患,同时还可使两表面上的阻焊油墨所受预烤的影响因素一致,有利于后续显影工序的控制,显影出精度更高的阻焊层。(The invention relates to the technical field of printed circuit boards, in particular to a method for improving the solder mask efficiency of a circuit board in screen printing. According to the invention, the screen printing auxiliary plate provided with the supporting block is used in cooperation with the screen printing auxiliary plate when the solder resist ink is screen-printed on the second surface of the PCB production board, screen printing can be immediately carried out on the second surface after the solder resist ink is screen-printed on the first surface, standing waiting for drying of the solder resist ink on the first surface and pre-baking are not needed, so that the time for first standing and pre-baking can be saved, the production efficiency is improved, the hidden quality trouble caused by oxidation due to the fact that the copper surface on the second surface is exposed in humid and warm air can be avoided, meanwhile, the influence factors of pre-baking on the solder resist ink on the two surfaces can be consistent, the control of the subsequent developing process is facilitated, and the solder resist layer with higher precision can be developed.)

1. A method for improving the silk-screen solder mask efficiency of a circuit board is characterized in that solder mask ink is silk-screen printed on a PCB production board, and the PCB production board is divided into the following areas: a board edge area, a unit board area, and a molding line area for isolating each unit board area; positioning holes are respectively arranged in the plate edge areas at the four corners of the PCB production plate; the method for silk-screen solder mask is characterized by comprising the following steps:

s1, solder resist ink is printed on the first surface of the PCB production board in a silk-screen mode;

s2, placing the PCB production board on a screen printing auxiliary board, wherein the first surface of the PCB production board faces downwards and is opposite to the screen printing auxiliary board, and screen printing solder resist ink on the second surface of the PCB production board;

areas which correspond to the board edge areas, the unit board areas and the forming line areas of the PCB production board one by one are divided on the screen printing auxiliary board, and supporting blocks are arranged on the board edge areas at three corners of the screen printing auxiliary board and at positions corresponding to the positioning holes;

s3, standing the PCB production board until the solder resist ink on the first surface and the second surface is dry and does not flow, and then sequentially carrying out pre-baking, alignment exposure and development treatment on the PCB production board to complete the manufacture of the solder resist layer on the PCB production board.

2. The method for improving the screen printing solder mask efficiency of the circuit board as claimed in claim 1, wherein a plurality of supporting blocks are arranged on the forming line area of the screen printing auxiliary board.

3. The method for improving the screen printing solder mask efficiency of the circuit board as claimed in claim 2, wherein the distance between two adjacent support blocks on the molding line area is 40 mm.

4. The method for improving the silk-screen solder mask efficiency of the circuit board as claimed in claim 1, wherein the board edge area of the PCB production board is provided with a routing vacancy, and a support block is arranged on the board edge area of the silk-screen auxiliary board and at a position corresponding to the routing vacancy.

5. The method for improving the screen printing solder mask efficiency of the circuit board as claimed in claim 1, wherein the board edge area of the PCB production board is provided with non-metallized hole sites, and the board edge area of the screen printing auxiliary board is provided with support blocks at positions corresponding to the non-metallized hole sites.

6. The method for improving the silk-screen solder mask efficiency of the circuit board as claimed in claim 1, wherein the PCB production board is provided with non-silk-screen positions on the board edge area, and support blocks are provided on the board edge area of the silk-screen auxiliary board and at positions corresponding to the non-silk-screen positions.

7. The method for improving the screen printing solder mask efficiency of the circuit board as claimed in claim 1, wherein a support block is provided on the unit board area of the screen printing auxiliary board, and the position of the support block is staggered with the position corresponding to the circuit provided on the PCB production board.

8. The method for improving the screen printing solder mask efficiency of the circuit board according to any one of claims 1 to 7, wherein the supporting block is covered with a solder mask ink layer formed by solder mask ink.

9. The method for improving the screen printing solder mask efficiency of the circuit board as claimed in claim 8, wherein the supporting block is adhered to the screen printing auxiliary board by an adhesive tape.

10. The method for improving the screen printing solder mask efficiency of the circuit board as claimed in claim 8, wherein the supporting block is composed of a flat plate and protruding pins protruding from the surface of the flat plate.

Technical Field

The invention relates to the technical field of printed circuit boards, in particular to a method for improving the solder mask efficiency of a circuit board in screen printing.

Background

In the field of circuit board production, circuit board resistance welding refers to coating resistance welding ink on circuits and base materials of which the surfaces are not required to be welded to form a protective layer for preventing bridging among the circuits during welding and serving as a protective layer for providing a permanent electrical environment and resisting chemical corrosion, and meanwhile, circuit board resistance welding also plays a role in beautifying the appearance. The circuit board solder mask is generally completed by screen printing and then by alignment exposure and development, and is also called screen printing solder mask. Except for a traditional single-sided board, the front side and the back side of a double-sided board and a multilayer board both need silk-screen solder resist, the flow of silk-screen solder resist generally includes that firstly, silk-screen solder resist ink is printed on one surface of a production board with the two sides being pretreated, the solder resist ink from the production board to the board surface is kept static and is pre-baked after being preliminarily dried, then, the silk-screen solder resist ink is printed on the other surface of the production board, the solder resist ink is kept static and is pre-baked again after being preliminarily dried until being on the surface, and then, a needed solder resist layer is formed on the production board through counterpoint. According to the silk-screen solder mask flow, after silk-screen solder mask ink is printed on one surface, silk screen printing can be carried out on the other surface only through standing and pre-baking, in the standing and pre-baking processes, the copper surface of the other surface which is subjected to pretreatment is exposed in humid and warm air and is easy to oxidize, so that potential quality hazards can be introduced, and on the other hand, the standing and pre-baking processes can cause production process congestion and the production efficiency is low.

Disclosure of Invention

The invention provides a method for improving the silk-screen solder mask efficiency of a circuit board by only carrying out one-time standing and pre-baking treatment, aiming at the problems that the existing silk-screen solder mask method of the double-sided circuit board needs two standing and pre-baking procedures, has low efficiency and leads to potential quality hazards because the copper surface on one side of the non-silk-screen solder mask ink is easy to oxidize.

In order to achieve the purpose, the invention adopts the following technical scheme.

A method for improving the silk-screen solder mask efficiency of a circuit board is characterized in that solder mask ink is silk-screen printed on a PCB production board, and the PCB production board is divided into the following areas: a board edge area, a unit board area, and a molding line area for isolating each unit board area; positioning holes are respectively formed in the plate edge areas at the four corners of the PCB production plate; the method for silk-screen solder resist comprises the following steps:

s1, solder resist ink is printed on the first surface of the PCB production board in a silk-screen mode;

s2, placing the PCB production board on a screen printing auxiliary board, wherein the first surface of the PCB production board faces downwards and is opposite to the screen printing auxiliary board, and screen printing solder resist ink on the second surface of the PCB production board;

areas which correspond to the board edge areas, the unit board areas and the forming line areas of the PCB production board one by one are divided on the screen printing auxiliary board, and supporting blocks are arranged on the board edge areas at three corners of the screen printing auxiliary board and at positions corresponding to the positioning holes;

s3, standing the PCB production board until the solder resist ink on the first surface and the second surface is dry and does not flow, and then sequentially carrying out pre-baking, alignment exposure and development treatment on the PCB production board to complete the manufacture of the solder resist layer on the PCB production board.

Preferably, a plurality of supporting blocks are arranged on the forming line area of the silk-screen auxiliary plate.

More preferably, the interval between two adjacent supporting blocks on the forming line area is 40 mm.

Preferably, the board edge area of the PCB production board is provided with a routing vacancy, and the board edge area of the screen printing auxiliary board is provided with a supporting block at a position corresponding to the routing vacancy.

Preferably, the PCB production board is provided with non-metallized hole sites on the board edge area, and the screen printing auxiliary board is provided with support blocks on the board edge area and at positions corresponding to the non-metallized hole sites.

Preferably, the PCB production board is provided with a non-silk-screen printing position on a board edge area, and a support block is arranged on the board edge area of the silk-screen printing auxiliary board and at a position corresponding to the non-silk-screen printing position.

Preferably, the unit board area of the screen printing auxiliary board is provided with a supporting block, and the position of the supporting block is staggered with the position corresponding to the circuit arranged on the PCB production board.

Preferably, in the method for improving the solder mask printing efficiency of the circuit board, the solder mask ink layer formed by the solder mask ink covers the supporting block in the screen printing auxiliary board.

Preferably, the supporting block is adhered to the screen printing auxiliary plate through an adhesive tape.

Preferably, the supporting block is composed of a flat plate and a convex nail protruding from the surface of the flat plate.

Preferably, the silk screen auxiliary board is 20mm larger than the single side of the PCB production board.

Compared with the prior art, the invention has the beneficial effects that:

according to the invention, the screen printing auxiliary plate provided with the supporting block is used in cooperation with the screen printing auxiliary plate when the solder resist ink is screen-printed on the second surface of the PCB production board, screen printing can be immediately carried out on the second surface after the solder resist ink is screen-printed on the first surface, standing waiting for drying of the solder resist ink on the first surface and pre-baking are not needed, so that the time for first standing and pre-baking can be saved, the production efficiency is improved, the hidden quality trouble caused by oxidation due to the fact that the copper surface on the second surface is exposed in humid and warm air can be avoided, meanwhile, the influence factors of pre-baking on the solder resist ink on the two surfaces can be consistent, the control of the subsequent developing process is facilitated, and the solder resist layer with higher precision can be developed. In addition, the support block of the silk screen auxiliary board is adhered to the silk screen auxiliary board through the sticky tape, the support block can be conveniently and quickly detached or adjusted to change the position, when the pressing condition exists between the circuit on the PCB production board and the support block, the support block and the circuit can be staggered by finely adjusting the position of the support block, so that the silk screen solder mask is efficiently and smoothly carried out, and the silk screen auxiliary board can be suitable for the production of circuit boards in different batches by adjusting and changing the position of the support block.

Drawings

FIG. 1 is a schematic view of a PCB production board according to an embodiment;

FIG. 2 is a schematic structural diagram of the silk-screen auxiliary plate in the embodiment;

fig. 3 is a schematic view of a support block having a bolt provided at a non-central position.

Detailed Description

In order to more fully understand the technical contents of the present invention, the technical solutions of the present invention will be further described and illustrated with reference to the following specific embodiments.