Manufacturing method of PCB large copper surface character

Abstract

The invention discloses a manufacturing method of a PCB large copper surface character. The method comprises the following steps: preparing a solder mask layer on a production board, and then, carrying out first pickling treatment on the production board; performing silk-screen printing of first surface character ink on the copper surface of one surface of the production board, and pre-curing thefirst surface character ink through pre-baking; carrying out second pickling treatment on the production plate; and performing silk-screen printing of second surface character ink on the copper surface of the other surface of the production board, and thoroughly curing the first surface character ink and the second surface character ink through baking. According to the method, the character manufacturing process is optimized, and before characters are manufactured on the large copper surface, the pickling process is added, so that the copper surface oxide layer obtained after high-temperatureboard baking is removed, the copper surface roughness is increased, the combination area of the copper surface and character ink is increased, and the problem of character dropping of the large coppersurface is solved.

Description

technical field [0001] The invention relates to the technical field of printed circuit board production, in particular to a method for producing PCB large copper-faced characters. Background technique [0002] The character process in the PCB production process refers to the transfer of a type of character ink to the circuit board surface by screen printing for the identification and installation of subsequent components and the provision of information such as production cycle and UL logo. Character ink production The principle is relatively simple, but due to various requirements in the actual production process, it is not easy to operate. Most of the character inks are mimeographed on the solder mask layer, and some PCBs need to design printed characters on the large copper surface due to special structural requirements. Existing character production technology mainly contains: [0003] 1. Conventional process: screen printing characters on the first side → post-baking ...

AI Technical Summary

Problems solved by technology

[0006] Among the above, the copper surface is easily oxidized after the conventional process of method 1 is baked at high temperature, which seriously affects the bonding force between the character ink and the copper surface. It is easy to intrude into the bottom layer of the characters when processing the copper surface, causing the characters to fall off, causing some characters to be unclear and affecting subsequent stickers and logos, etc., resulting in the failure of character production

[0007] The patented technology 201020530989.4 of method 2 lays solder resist ink under the character ink, and utilizes the characteristic that the bonding force between the character ink and the solder resist ink is better than that of the copper surface, avoiding the direct contact between the character ink and the copper surface, and improving the character during surface treatment. The defect that it is easy to fall off after being treated with liquid medicine. The disadvantage is that the alignment between the character ink and the solder resist ink is difficult, and it is very easy to expose the solder resist ink below, or shift to the copper surface, which increases the difficulty of the process and affects the appearance of the finished product. In addition, This process also needs to consider the problem that the oxidation of the copper surface affects the bonding force between the solder resist ink and the copper surface

[0008] The patent 201621071187.5 of method 3 grooves on the copper surface. This method is beneficial to improve the bonding force between the solder resist ink and the copper surface, and further optimize the stability of the character ink. The disadvantage is also that the alignment between the character ink and the solder resist ink is difficult, which increases the process. Difficulty, in addition, slotting on the copper surface will affect the integrity of the large copper surface and affect its functionality, and some customers do not agree to slotting