Graphic overlay, Membrane Switch Board

Graphic overlay, Membrane Switch Board

The graphic overlay is a polyester or polycarbonate foil. Most of the cases it is screen printed on the back by different colours, sometimes embossed and in case of matt foils at the transparent parts (for example display) it is vitrified or has a coloured transparent window. This foil has very good physical and chemical features.The graphic overlay can be a product itself! With or without adhesive foil. The membrane switch board can be determinated according to the following three components:The membrane switch board can be determinated according to the following three components: Graphic overlay, Base material, Connecting elements.

Circuit boards

Flexible Circuit boards

The production of flexible circuit boards was introduced after technologic experiments that had been finished at the end of 2002. In the first step we spezialized on the single sided flex PCB. In the 360.000 EUR investment that we did by the end of 2002 we already took the technologies needed for the production of flexible PCBs into consideration. From the beginning of 2003 we have started the manufacturing of double sided flex PCB using polyimid base material. By the middle of 2004 all process development relating to the production of flexible multilayer and rigid-flexible combination PCBs will be completed. The introduction of flexible PCBs using different types of metal conductor material is also planned for the end of this year.

Flexible circuit board

Flexible circuit board covered by copper foil

We use polyimid or polyester base material, as base foil for the production of flexible PCB. In case of polyimid the width of raw material is expected to be 25-50 micron, in case of polyester 50-125 micron. The copper thickness can be between 18 and 35 micron. The production technology is similar to the traditional rigid PCB manufacturing. The most important thing is to avoid that the whole surface of the created circuit has the tin, tin-lead or gold plating. The cover on the copper can make the PCB panel brittle with losing its flexibility. Of course we use this technology on the pad and connectors. There is a possibility to create circuit, we can fix the components by soldering. In case of PET we should use smaller soldering surface (IC, resistance etc…) because the basic material can not bear the long soldering process, the base foil wrinkles. End mechanic process can happen by simple cutting, "stanz" or laser cutting.

Flexible circuit created on PET based material

Flexible circuit created on PET based material with conductive ink

We use this type of flexible circuit board typically for production of membrane switch board. We screen print the conductive layer to the heat stabilized foil and then we cure at the suitable tempreture.There is possibility to create circuits, which it is possible to fix the components by conductive ink on.

Rigid-flex combinated printed circuits

Rigid-flex combinated printed circuits

The flexible printed circuits have been used only in special areas in the past. Parallel to the miniaturization of the components the demand for the compaction of construction method appeared in case of some equipments (cell phones, digital cameras etc.), which was possible by using the rigid-flexible circuits. The application of these circuits has strongly enlarged the security of service of the equipments and helped this technology to become popular in the automotive industry. 

Aluminum supported printed circuits

Aluminum supported printed circuits

The aluminum supported printed circuits (Thermal Clad, Insulated Metal Substrate (IMS®)) area of use are generally such a place where during operation a large amount of heat is generated in the components: Power transformers, power LED applications, solid state relay applications, motor controllers.