Important characteristics of FPC base material of non adhesive soft board:
FPC base material
- Heat resistance
The FPC base material of non adhesive soft board has excellent heat resistance due to the absence of adhesives with poor heat resistance, and the long-term use temperature can reach more than 300.
- Dimensional stability
The size change of FPC substrate of non adhesive soft board is relatively small affected by temperature. Even at high temperature (300 ℃), the size change rate is still within 0.1%, but the size change rate of three-layer adhesive soft board is greatly affected by temperature. Good dimensional stability will be of great help to the thin line manufacturing process, and FPC without glue will become the mainstream of the information electronic product market.
- Chemical resistance
The chemical resistance of FPC base material of non adhesive soft board is quite excellent, and the tear resistance has no obvious change over a long period of time, while the three layer adhesive soft board base material has poor chemical resistance due to the poor adhesive, and the tear resistance decreases significantly with time.
Other characteristics of FPC substrate for non adhesive soft board include that it can reduce the thickness of the substrate, which conforms to the trend of light, thin and short. In addition, because the residual amount of chloride ions after etching is low, it reduces the ion mobility, and also reduces the long-term reliability of thin circuits.
Manufacturing method of FPC base material of non adhesive soft board:
FPC base material
With PI film as the substrate, a metal layer is deposited on the PI film by vacuum sputtering, and then the copper thickness is increased by electroplating.
(2) Coating method:
With copper foil as the base material, the synthesized polyamide acid is extruded and coated on the rolled copper foil with a precision die, dried in an oven and then acylated to form a non adhesive soft board FPC base material.
(3) Hot pressing method:
First, a thin layer of thermoplastic PI resin is coated on the PI film as the substrate, and then the thermoplastic PI is hardened at high temperature, and then remelted at high temperature and high pressure. The thickness of copper foil is also difficult to be less than 12.