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The concept of PCB:

　　Circuit boards, generally refer to circuit boards. It can be called printed circuit board or printed circuit board, and its English name is PCB. Its purpose is to miniaturize and visualize circuits. It plays an important role in mass production of fixed circuits and optimizing the layout of electrical appliances. Generally, PCB raw materials are divided into rigid base material and flexible base material.

　　Manufacturing process of PCB:

　　Divide incoming material inspection - tapping - Drilling - sinking copper - plate surface plating - graphic transfer - Graphic plating - etching - resistance welding - character printing - appearance processing - appearance processing - circuit testing - final product inspection - final product warranty - packaging. In actual operation, it is divided into feeding - bulking - washing - degumming - washing - neutralization - washing - etching - washing - pre - Immersion - activation - washing - recovery - washing - Copper carbide - washing - acid - dipping - electroplating - washing - drying - extracting board.

　　Antifoaming Agent plays an important role in PCB cleaning

　　Defoamer is used in PCB cleaning, PCB water treatment, film removal, etching, development and sewage treatment (PCB process). Especially in the dry film process during the production of printed circuit boards, the unexposed dry film is removed by developing. The dry film is a photosensitive insulating resin and the developer is a sodium carbonate solvent. Due to the continuous dissolution of the dry film, the developer will generate a certain amount of foam in the system circulation spray process, and the foam will affect the quality of the development to a certain extent, which will make it inconvenient to produce.

　　Specific features are as follows:

　　1、 Defoaming, anti-foaming ability is strong, simple water is loose, less dosage, does not affect the fundamental nature of the foaming system.

　　2、 Good heat resistance, strong alkali resistance, chemical stability, non-corrosive, non-toxic, no adverse side effects, non-flammable, non-explosive.

　　3、 Its function is comparable to that of imported products, and its price has obvious advantages.

　　Silicon-free defoamers are also used in the industry, which are composed of special ether ester surfactant additives, etc. They have good defoaming and anti-foaming functions, will not form residual tank walls, good washing, will not produce oil slick, floating oil, sticking board and other phenomena, and have no effect on the subsequent processing. Silicon-containing defoamers are suitable for defoaming and anti-foaming under alkaline conditions, because they are emulsified with special emulsifiers and have a wide range of acid and alkali resistance (suitable for PH3-13 environment).

The article originated from Jiangmen single-sided and double-sided circuit boards. http://m.jzfwq.com/