FPC flexible circuit boards are characterized by lightness, thinness and shortness, so they are also the best choice for most intelligent electronic products. Flexible circuit boards are also prone to operations such as bends, folds, and scars during use. They have low mechanical strength and are easy to crack. Therefore, the purpose of the stiffener is to strengthen the mechanical strength of the FPC flexible circuit board, and to facilitate the installation of parts on the PCB surface. There are many types of stiffener films used in the flexible circuit board. There are PET, PI, adhesive, metal or resin reinforced board and so on.
1. The main process of FPC flexible circuit board reinforcement board
PCB production process: cutting (copper foil protective film reinforcement board PSA) - drilling (copper foil protective film reinforcement board PSA) - black holes or PTH - sticking dry film - film alignment - exposure - development - copper plating -Remove dry film-Chemical cleaning-Apply dry film-Film alignment-Exposure-Development-etch Text - Baking - Surface Treatment - PSA Pasting - Splitting - Lead Punching - Electrical Inspection - Punching Shape - FQC (Full Inspection) - OQC - Packaging - Shipment
Second, the reinforcement board fits
1. Hot-pressurized reinforcing plate: At a certain temperature, the thermo-hardening glue of the reinforcing plate film begins to melt, so that the reinforcing plate film sticks to the product, and the reinforcing plate is positioned.
2. Pressure sensitive reinforcement board: without heating, the reinforcement board can be glued to the product.
Third, the reinforcement board is pressed together
1. Hot-compressive reinforcement board: Use high temperature to melt the heat-hardening glue of the reinforcement board film, and use appropriate pressure or vacuum to make the reinforcement board film tightly fit on the flexible circuit board.
2. Flexible circuit board pressure sensitive reinforcement board: no heating is required, and the product is pressed by a cold press
Four, maturation
For the hot-pressurized reinforcing plate: the pressure during pressing is small and the time is short. The thermo-hardening glue of the reinforcing plate is not completely aged. It needs to be baked at high temperature for a long time to completely aging the glue and increase the reinforcing plate and products. The adhesion.
Fifth, the introduction of flexible circuit board PCB equipment
Refrigerator: store the reinforcing plate film that needs to be refrigerated
Pre-attachment machine (C/F laminating machine): laminating hot-pressurized reinforcing plate film
Manual laminating fixture: laminating cold-pressurized reinforcing plate film
Vacuum machine: laminating the finished product of the hot-pressurized reinforcing plate
80 ton fast press: laminating the finished products of PI thinner hot-compressive reinforcing plate
Cold press: press the cold-compressible reinforcing plate
Oven: Baking the finished product of the hot-pressurized reinforcing plate
Six, FPC flexible circuit board use fixture introduction
Pre-sticking fixture:
Location PIN:
Seven, Stiffener Film
Reinforcement board film: The mechanical strength of the reinforcement board FPC flexible circuit board, which is convenient for surface mounting operations. Common thicknesses are 5mil and 9mil.
Adhesive: It is a kind of thermosetting adhesive or pressure sensitive adhesive, and the thickness is determined according to customer requirements.
Release paper: Avoid the adhesive sticking to foreign objects before pressing.
Store the reinforcing plate film that needs to be refrigerated according to the requirements on the material card
Refrigeration temperature: 1~9 degree Celsius, shelf life under refrigeration conditions is 3 months
The flexible circuit board reinforcement board material can not be stored for more than 8 hours at room temperature