Cirlex® is an all-polyimide adhesiveless lamination product made from Kapton®. Lohmann says this sheet material is ideal for replacing ceramics and high performance plastics in some applications, or as an expedient project upgrade. Because the new material offers design flexibility it can be used in applications where cast resins or laminated constructions using adhesives just won’t work, and offers the additional advantages of being chemically inert and abrasion resistant too.
Cirlex® provides design engineers with greater structural strength than alternatives due to its monolithic polyimide construction, with no adhesive weak points, and is also resistant to all known organic solvents. Coupled with excellent mechanical integrity and a dielectric strength of 2790v/mil, the new material is a true high performance option for electronics designers and is available from Lohmann Technologies in a usable choice of sheet sizes. Interestingly, for flexible circuits, Cirlex® can also be specified with metallized layers on a single side, two sides, or even embedded into the material itself effectively making it into a ‘clad’ laminate.
Offering a unique combination of multiple layers of Kapton® and available in thicknesses from 0.15mm to more than 3mm (in .0254mm increments), this latest addition to the armoury of the electronics engineer opens up significant new opportunities for enhanced thermal insulation, heat management and electrical isolation.
Further, unlike many alternative materials, Lohmann’s new Cirlex® laminate maintains exceptional tolerances when subjected to standard manufacturing operations and processes including laser cutting, CNC drilling and machining and in some cases, stamping as well as chemical etching.
Lohmann observes that traditional laminates are notoriously unreliable at temperatures which exceed the Glass Transition (Tg) of the adhesives used in their construction, and as standard, Cirlex® operates at -269° Celsius to +351° Celsius. Cirlex® laminated with copper or other foils has a top operating temperature of 220° Celsius. Furthermore, the material provides a standard flammability rating of UL 94V-0, and also meets NASA Standard S-311-P-841 General Specification for thermofoil heater in all-polyimide space applications, which may be a matter of some gravity to Earthbound electronics engineers.
Lohmann’s Electronics Industry Sales Manager Colin Theaker says “In layman’s terms one might refer to Cirlex® as a supercharged version of Kapton®. This addition to an already extensive portfolio of bonding, sealing, and thermal management solutions from Lohmann is at the top end of the technology spectrum, so much so that many of the applications in which it is already being used are Classified. However, we can say that great use is being made of it in the aerospace and defence sectors, as well as in mass production applications in the wider electronics sector, together with medical and automotive projects. Typical uses include flex circuits, medical diagnostic equipment, high power busbars, and spacecraft, just to name a few”.
