Anti-welding procedue of PCB

Abstract

The invention provides an improved solder mask structure to prevent the variation of electrical character and comprises: the step of coating the resin, making a steel plate with a large hole on the portion to be exposed, the resin is coated on the contact portion to be exposed and totally covers the contact portion; the step of covering mask, making a steel plate for coverage on which a hole in a designed size is opened, and covering the steel plate for coverage on the coated resign; the step of ultraviolet radiation, after ultraviolet radiation, the resin on the portion of opening hole is solidified; the step of spraying insulation finish, spraying the insulation finish on the PCB, and then solidifying it; the step of removing the insulation finish and resin, removing the insulation finish and resin on contact portion to be exposed using dull polish or sand blast; after washing, the contact portion is kept an exposing state, and other portion of the PCB is covered by the insulation finish.

Description

technical field [0001] The invention belongs to an auxiliary manufacturing method for circuit board manufacturing, in particular to a PCB solder-proof process. Background technique [0002] In the existing PCB solder mask process, usually after the printed circuit is completed, the film corresponding to the circuit is exposed to make a mesh body, and then coated with ink printing on the part of the PCB other than the exposed contacts. [0003] This existing PCB solder mask process has the following disadvantages: [0004] 1. More consumables are used, and the manufacturing time is longer, which increases the cost. [0005] 2. Ink coating is thick and thin, which is easy to produce impedance changes and affect electrical characteristics. [0006] 3. Because the ink is required to be evenly coated, more sophisticated equipment is required, which increases investment and production costs. [0007] 4. Since the existing manufacturing process is image transfer technology, more...

AI Technical Summary

Problems solved by technology

[0004] 1. More consumables are used, and the manufacturing time is longer, which increases the cost

[0005] 2. The thick and thin ink coating is uneven, which is prone to impedance changes and affects electrical characteristics

[0006] 3. Because the ink is required to be coated evenly, it is necessary to use more sophisticated equipment, which increases investment and production costs

[0007] 4. Since the existing process is image transfer technology, more equipment is used and the process is longer

[0008] 5. Since the film used is quite sensitive to the ambient temperature, there will be a difference in size with the change of the ambient humidity, and the stability is low

[0009] In addition, the existing solder mask structure is monotonous in color, lacks change and is easy to scratch, which is not ideal

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