Understanding Interlayers in Printed Circuit Boards and Composites

Interlayer refers to the space or gap between two layers of material, such as between the layers of a multi-layer printed circuit board (PCB) or between the layers of a composite material. Interlayers are often used in PCBs to improve the thermal and mechanical properties of the board, and in composites to enhance the bonding between layers.

In PCBs, interlayers can be made of various materials, such as glass fibers, aramid fibers, or thermosetting resins. These materials help to dissipate heat generated by the electronic components on the board, improve the thermal conductivity of the board, and reduce the risk of delamination or cracking.

In composites, interlayers can be made of materials such as paper, fabric, or thin films. These materials help to distribute stress and strain between the layers of the composite, improve the bonding between layers, and enhance the overall mechanical properties of the composite.

Interlayers can be applied in various ways, depending on the specific application and requirements of the PCB or composite. Some common methods of applying interlayers include:

1. Laminating: Interlayers are laminated onto one or both surfaces of a substrate using a specialized adhesive.
2. Injecting: Interlayers are injected into a mold containing a substrate, where they are bonded to the substrate through heat and pressure.
3. Coating: Interlayers are applied as a thin layer onto a substrate using a coating process such as spraying or brushing.
4. Printing: Interlayers can be printed onto a substrate using a specialized inkjet printer or other printing technology.

Overall, interlayers play an important role in enhancing the performance and properties of PCBs and composites by improving thermal conductivity, mechanical strength, and bonding between layers.