Shenzhen Blue Spectrum Rick Technology Co., Ltd. Ultraviolet curing process has been used in circuit board coating industry for more than 25 years. It has a large number of R&D teams, carefully designed customized products, and has achieved coating and curing in various fields. Ultraviolet UV LED curing technology is used to make the production faster, more convenient, more environmentally friendly and efficient.
Liquid photoresist (commonly known as green oil) is a kind of protective coating, which is applied to printed circuit boards (PCBs) without welding on the circuit and substrate, or used as solder resistance. The purpose is to form a long-term protection of the line graphics.
The main components of liquid photo-imaging solder-resistant ink include epoxy resin and acrylic resin with photosensitive properties, such as propylene glycol epoxy resin, phenolic epoxy resin, mesophenol epoxy resin and ethyl aminocarbonate, etc., photoinitiator, such as thioanthrone, benzophenone, carbonyl compound, ketone, amine organic metal compound, etc. Fillers, such as silica powder; hardeners, such as aromatic lipids, anhydrides, imidatives; solvents, such as ether esters; defoamers, etc. The coating method generally uses screen leak printing, which is similar to wet film.
Its functions are as follows:
(1) Preventing physical disconnection of conductor circuits;
(2) In welding process, to prevent short circuit caused by bridge connection;
(3) Only the parts that must be welded should be welded to avoid waste of solder.
(4) Reducing copper pollution to welding tank;
(5) To prevent deterioration and corrosion of insulation caused by external environmental factors such as dust and moisture;
(6) High insulation makes it possible to densify the circuit.
Solder Mask, English, has many colors, such as red, blue, green, purple, white, black and so on. Because green is the most commonly used, many people also call it green oil. Welding resistance green oil is a common term in mainland China, while in Taiwan it is called welding resistance. Personally, I think this term is more appropriate.
Weld resistance ink is sticky before use. Through printing, pre-drying, alignment, exposure, development, post-curing and other operation processes, it will be necessary to expose all the welding or assembly positions of the end-users, without the need to weld or assemble the base material, copper foil positions all covered with welding resistance ink, such a layer of resistance. The welding layer has excellent acid and alkali resistance, solvent resistance and high temperature resistance.
The solder barrier layer has several functions on PCB board:
1. Cover the substrates between lines to prevent short-circuit between lines.
2. Cover all conductive lines that do not need to be welded to prevent oxidation of copper layer, and connect conductive lines to short circuit in the process of surface treatment.
3. Prevent tin short-circuit between conductive lines and pads during reflow soldering, wave soldering and manual soldering in client.