The original material of the circuit board is copper clad board. The substrate is a resin plate with copper on both sides. Now the most commonly used plate code is FR-4. FR-4 is mainly used in computer, communication equipment and other grades of electronic products. Requirements for the plate: one is the flame resistance, two is the Tg point, the three is the dielectric constant. Circuit board must be resistant to burn, can not be burned at a certain temperature, can only be softened.
2, copper foil
The wire conductor copper foil is formed on the substrate, the manufacturing process of copper foil has two kinds of methods: rolling and electrolysis.
PP is an indispensable material in the production of circuit boards, it is the role of the layer of bonding agent. In brief, the substrate in the B-stage is called the PP. PP specification is the thickness and the amount of plastic (resin).
4, dry film
The photosensitive film is referred to as the dry film, the main ingredient is a resin material sensitive to specific spectral and photochemical reaction. The utility dry film has three layers, and the photosensitive layer is clamped between the upper and the lower two layers of the protective action of the plastic film. According to the chemical characteristics of photographic materials, there are two kinds of dry film, photo polymerization type and light decomposition type. The photo polymerization type dry film can harden under the special spectrum of light, and the water soluble substance is changed into water insoluble, and the light is just the opposite.
5, anti welding paint
The solder resist is actually a solder resist, it is a liquid photosensitive material that does not have affinity to the liquid solder. It is the same as the photosensitive dry film. When in use, the solder resist is also mixed with the stiffening agent in the use. Solder resist ink. The color we usually see on the circuit board is actually the color of the paint.
We say that the film is similar to the photographic film, is the use of photographic materials to record the image of the material. Customers will be designed to the circuit board to the circuit board factory, the CAM center of the station will be the output of the line, but not through the common printer, but the light. The role of the negative in the circuit board factory is important, all the use of image transfer principle, to do the things on the substrate, the first to become negative.