Pure FR4 Rigid-Flex
The Pure FR4 rigid-flex is a variant where the flexible section is replaced with thin FR4. It remains flexible enough for installation but offers greater robustness and bend resistance than semi-flex.

Pure FR4 Rigid-Flex Technology | Design and Manufacturing Benefits | Application Areas | Material Properties | Quality Standards

Pure FR4 Rigid-Flex PCBs – Reliable Integration of Rigid and Flexible Areas

A variation of normal rigid-flexible printed circuits

Starrflex Leiterplatte

is the "pure-FR4-rigid-flex". Here we ahve a standard rigid-flex with the same manufacturing process, except that the flexible part is replaced by a very thin FR4 core. This PCB is then still flexible enough for installations and performs better than semi-flex in this regard. This "pure-FR4-rigid-flex" allows smaller bending radius than semi-flex PCBs.

What are the advantages of pure-FR4-rigid-flex?

The big advantage compared to standard rigid-flex PCBs is the absence of Polyimide. This means that the whole board has a far lesser hygroscopic (absorbs less humidity) tendency, which is critical for some applications. Although the manufacturing process is almost identical to standard rigid-flexible boards, they are also slighty cheaper. This is due to the fact that pure FR4 stack-ups are easier to laminate than hybrid-stack-ups.

Roughly the following characteristics apply:

dynamic bending performanceflex-to-install bending performancecosts
semi-flex none fair $
pure-FR4-rigid-flex none good $$$$
rigid-flex good very good $$$$$

Bitte fragen Sie Pure-FR4-Starrflex Leiterplatten per E-Mail an.

Climate-neutral operation
since 2021
  • CO2 neutral through compensation
  • Circuit boards – green on the outside, also on the inside
Member of the Fachverband Elektronik-Design
  • Expertise through active exchange
  • Expertise through training and further education
ISO tested by the most renowned auditor in Germany
  • ISO 9001:2015 Quality Management
  • ISO 14001:2015 Environmental Management
UL approvals for various types of circuit boards
  • UL for rigid FR4 PCBs
  • UL for flexible circuit boards
  • UL for aluminum IMS boards