What are the important raw materials of PCB PCB

Circuit board will appear in almost every type of electronic equipment, it is the carrier of all electronic equipment, computer inside is filled with PCB figure, small to home appliances in everyday life, big to on-board electronic devices, but in the process of PCB manufacturing need what material?Here is a brief analysis:

1, the substrate

The original material of the circuit board is copper clad substrate, or substrate.The base plate is a resin board with copper on both sides.The most commonly used plate code is fr-4.Fr-4 is mainly used for electronic products such as computer and communication equipment.The requirement of plate: one is flame resistance, two is Tg point, and three is dielectric constant.The circuit board must be resistant to combustion and can not be burned at certain temperature.

2, copper foil,

Copper foil is a conductor forming a conductor on a substrate, and there are two ways to make copper foil: calendering and electrolysis.

3, PP.

PP is an indispensable raw material in the production of circuit board, and its function is the adhesives between layers.In short, the substrate in the b-stage is called the PP.The specification of PP is the thickness and the amount of glue (resin).

4, dry film

Photosensitive dry film, or dry film, is mainly composed of a kind of resin material which has photochemical reaction to specific spectral sensitivity.The practical dry film has three layers, and the photosensitive layer is sandwiched between two layers of protective plastic film.According to the chemical characteristics of the photosensitive material, there are two types of dry film, photopolymerization and photodecomposition.Photopolymerized dry membranes harden in light of specific spectra, from water-soluble substances to water insoluble, while photodecomposition is the opposite.

5. Anti-welding paint

In fact is a kind of resistance welding paint flux, is to have affinity liquid solder is not a kind of liquid photosensitive material, it and photosensitive dry film, under the light of the specific spectrum will change and hardening.When used, it should be used with the hardener in the anti-welding paint.Anti - welding paint is also called ink.The color of the circuit board we usually see is actually the color of the anti-welding paint.

6, film

The film we talk about is similar to the photographic film, which is used to record images with photographic materials.The customer will send the designed circuit diagram to the circuit board factory, which will output the wiring diagram from the workstation of the CAM center, but not through the common printer, but the drawing machine.The film is very important in the circuit board factory, all the use of the principle of image transfer, to achieve the substrate, all must first become a negative.