How a membrane switch
works and is constructed
Eine Folientastatur besteht aus mehreren Folien- und Klebeschichten.
The standard structure of our flexible keyboards always consists of 6 individual layers.
Frontfolie: Sie besteht aus einer widerstandsfähigen Polyesterfolie, die mit einem individuellen Design im Digital- oder Siebdruck bedruckt wird.
Kleber: Die Klebeschicht verbindet die Frontfolie (Dekorfolie) mit der Haltefolie.
Haltefolie: Sie fixiert die Schnappscheibe auf der Leiterbahnfolie und hält diese dauerhaft an ihrer Position, um Funktionsausfälle zu vermeiden.
Spacer foil: The spacer foil optimally compensates for the height of the contact springs and connects the retaining foil with the conductor track foil.
Conductor track foil: This layer forms the electrical function of the membrane switch. The conductor tracks are printed with silver conductive paste according to an individual circuit diagram and fitted with contact springs and LEDs. The use of a printed circuit board is also possible as an option.
Adhesive: The final adhesive layer enables the membrane switch to be easily and securely integrated into the customer’s application. As an option, we can also supply the membrane switch pre-assembled on a carrier plate or already integrated into an enclosure.
More information about membrane switches in the Induux Wiki.
Your membrane switch. Your scope of performance.
From the flexible membrane switch to the integrated HMI solution:
Sie bestimmen, welche Funktionenen und Komponenten Ihre Anwendung benötigt.
We combine the right technologies and, on request, also handle the integration.
2. Expand your membrane switch
Embossing + doming
Keys with embossing or applied key caps (doming) provide optimal finger guidance and even enable blind operation. The raised areas can be individually designed and achieved at heights of up to 1 mm.
Lighting
Our key illumination in a wide range of colors impresses with its high brightness and long service life. Illuminated membrane switches can be flexibly realized on printed circuit board or on PCB.
Touchscreen + display
Hybrid HMIs, such as membrane switches with touchscreen or display, offer users proven key operation combined with modern touch functionality. The touchscreen/display is bonded to the membrane switch assembly using an adhesive frame or full-surface OCA bonding.
Housing + carrier
Membrane switches can be mounted on an individual carrier plate or housing for better stability. This protects electronic components and facilitates installation in the customer’s application.
Safety Features
An integrated EMC shield protects the membrane switch from electromagnetic interference. For safety-critical applications, membrane switches with dual-contact technology enable two clearly distinguishable switching points with different actuation forces.
Seals + Protection
Precisely dispensed seals protect membrane switches from water and dirt. UV-stabilized polyester films are suitable for outdoor use. Antimicrobial films provide additional protection against bacterial contamination in hygienically demanding areas such as medical technology.
3. Complete solution tailored to your requirements
You receive a 360° worry-free package: one solution, one point of contact!
We take care of the time-consuming coordination of many individual components and services for you.
You define the scope!
Operating unit
Buttons, touch, printed electronics, or a combination of multiple technologies.
Housing
Standard housing or a custom housing solution made of plastic or metal
Electronics
Custom-populated PCBs and LED technology for button backlighting.
Software
Intelligent user guidance or protocols for smooth data transmission
Connectivity
Custom interfaces and IoT connectivity for value-added HMIs
Design + Development
Quality + Sustainability
Typische Einsatzgebiete
of membrane switches
Medical technology:
Device operation with disinfectable surfaces and tactile feedback
Mechanical engineering:
Machine controls with haptic keys for glove and blind operation
Semiconductor industry:
EMC-protected, cleanroom-compatible operation with tactile feedback
Mobility:
Robuste beleuchtete Folientastaturen zur Steuerung von Zusatzfunktionen in Sonderfahrzeugen
Technical data for membrane switches
All technical data may vary depending on the customer-specific design.
Conductive and contact materials
Gold, silver, copper, carbon
Maximum switching voltage
AC 25 V / DC 42 V
Maximum switching current
100 mA
Maximum switching power
1.0 W
Service life
Min. 1 million switching cycles
Actuation force without contact element
2 – 5 N
Actuation force with contact element
2.5 – 4 N
IP protection class
up to IP69K
Operating temperature
-40 °C to 70 °C
Design films
Polyester, matte, glossy, and anti-glare
Circuit layout
Key arrangement in matrix, common control line, or with electronics according to circuit diagram
Embossing
Surface or frame embossing, standard height 0.3 mm (up to 0.7 mm possible)
GT-Doming
Custom shapes, standard height approx. 1 mm
FAQ:
Frequently asked questions about membrane switches
Membrane switches offer a high degree of customization. Size, shape, print, surfaces, lighting, connection options can be
can be freely customized. Transparent windows for displays, integrated LEDs or embossed key surfaces are also possible. So
creates an input system that fits perfectly into the design and functionality of your product.
Design:
The top layer of the membrane switch, the front foil, is screen printed. A wide range of RAL-classic colors is available for this purpose,
Pantone or HKS to choose from. Special colors according to the customer CI, a disappearing effect or a metal look with reflection are possible.
also possible.
Mechanics:
The size and shape of the membrane switch is fully adapted to the design of the device. Button sizes and positions, installation and
Fastening options and even tolerance specifications can be customized.
Electronics:
In addition to the snap domes for the buttons, LEDs can also be integrated for individual lighting. The circuit diagram and the
Connection (cable, plug, number of poles) of the membrane switch can also be customized. An integrated electronics assembly on a
Printed circuit board is possible.
Haptics:
In addition to different surface textures on the front foil, additional embossing (surfaces, frames, symbols) or GT domes can also be added to the front foil.
Improve user-friendliness.
Membrane switches consist of several resistant polyester layers. Depending on the structure and material, they achieve several
million actuation cycles per button. The closed surface provides reliable protection against mechanical wear, dust and dirt and
ensures constant functionality over many years.
Yes, membrane switches are particularly resistant to environmental influences due to their closed surface. Depending on
The products can be manufactured to protection classes such as IP65 or higher and are therefore resistant to dust and moisture. The used
Polyester films are also resistant to many cleaning agents and disinfectants. Membrane switches are therefore also suitable for
Ideal for hygienic environments, such as food or medical technology.
Yes, membrane switches can be designed to work reliably outdoors. UV-resistant
and temperature-resistant materials are used. In addition, protection types and temperature suitability can be individually adapted so that
the keyboards remain reliably functional at operating temperatures of – 40 °C to 70 °C. Sufficient edge bonding, special
Adhesives or additional seals make a membrane switch ready for outdoor use.
GT technology is a process developed by Hoffmann + Krippner to produce a dome-shaped, high-gloss plastic material with a high gloss finish.
onto a film surface. GT stands for casting technology. The GT domes are mainly applied to key surfaces,
to improve tactility and enable optimum finger guidance (for blind operation). The plastic mass is extremely
Resistant to mechanical influences. Pressure marks caused by hard objects can “heal” without leaving any residue.
Hoffmann + Krippner has been developing and producing customized membrane switches “Made in Germany” for decades. Customers benefit
from a unique combination of many years of experience, state-of-the-art production technology and individual advice. Every keyboard
is precisely tailored to the requirements of the application – from design and feel to material selection and special protection and
Hygiene functions. Thanks to our in-house development and production expertise, we can guarantee the highest quality, short distances and
guarantee reliable series production.
Folientastatur oder Touch – welche
technology suits my project?
Touch systems offer individually customizable user interfaces and enable a modern, intuitive user experience.
Membrane switches impress with durable,
reliable technology featuring clear tactile feedback and
manageable acquisition costs.
Start your project!
New development or redesign?
We are your partner from prototype to series production.