Graphic Overlays China offer a variety of Membrane Switches, including: Custom Membrane Switches, Membrane Keypads, Membrane Switch Panels, Control Panels, Metal Dome Membrane Switches, Keypad Switches, Membrane Switch Overlays, EL Membrane Switches, LED Membrane Switches, Tactile Membrane Switches and Non-tactile Membrane Switches.
Membrane switches, also called membrane keypads, are built from thin polycarbonate or polyester film and pressure sensitive adhesive.
Membrane switches are manufactured by screen printing the circuit directly onto a plastic substrate with silver or carbon conductive ink. Its simple, versatile, durable, and economical design make it a superior alternative to the mechanical switch.
Components of a Membrane Switch
- A membrane switch typically has the following basic layers
- Graphic overlay with subsurface printed text/graphics
- A polyester or polycarbonate layer with or without embossed keys
- ESD Shielding layer (optional)
- Spacer and/or Dome Retainer
- Polyester printed circuit layer, connector
- Rear adhesive with liner
Membrane Switch Materials
Membrane switches are made up of two flexible printed circuits, physically separated by a spacer. When the button is pressed, holes in the spacer allow the two circuits to contact completing the circuit. The printed top layer is known as the Graphic Overlay. It is normally made of clear polycarbonate or polyester, and reverse printed to protect the image from wear, solvents and abrasion.
Membrane switches, when combined with components such as a tactile dome, graphic overlay, or integrated LEDs or resistors can provide the designer with virtually limitless capabilities to create the ideal custom user interface for their products.
Membrane switches are a thin durable form of momentary switching that is commonly used throughout industry. Membrane switch is made of several layers including soft insulating material and electric material, with free lock and touch feature. It is assembled with the function of switch, front panel, graphic overlays, LCD Transparent windows, imbedded LED, soft circuit panel, male connector and electroluminescent (EL) backlighting.
Membrane Switch Materials: LEXAN Polycarbonate (PC) VS Polyester (PET)
The graphic overlay surface or faceplate material is one of the main considerations in designing a custom membrane switch, with polycarbonate and polyester being the most commonly used materials.
Polycarbonate is clearer, easier to fabricate and print but is less durable in constant use. Polycarbonate is slightly less expensive than polyester but the difference is minimal and not usually a major consideration.
Polyester is more challenging in its manufacturing, but is more durable and has better resistance to environmental conditions.
View our graphic overlays for detailed information on these materials. Polycarbonate Graphic Overlays & Polyester Graphic Overlays.
Applications for Membrane Switches
Membrane switches can be used in a great variety of low-voltage applications, from microprocessor-based systems to data entry pads and digital control panels. Membrane Keypads is widely used in many consumer products as well as many industrial applications like home appliance(microwave ovens and stoves), communication facility, industrial control panels, industry instrumentation, household appliances, retail equipment, consumer products, manufacturing, electronic and medical equipment.
Specification of Membrane Switches
Mechanical
- Actuation Force: Non-tactile 50g to 350g, Tactile 150g to 400g
- Switch Stroke: Non-tactile 0.1 to 0.5mm, Tactile 0.6 to 1.5mm
- Life Expectancy: Non-tactile >5 million actuations, Tactile >1 million actuations
Electrical
- Circuit Rating: 35V(DC), 100mA, 1W
- Operating Voltage: 35 volts maximum
- Operating Current: 10 micro amps to 100 milliamps, resistive
- Operating Power: 1 watt maximum
- Circuit Resistance: 10Ω-500Ω, dependent on size and layout
- Insulation Resistance: 100M ohms at 100V DC
- Dielectric Withstand: 250VRms(50~60Hz 1min)
- Contact Bounce: ≤ 5 milliseconds
Environmental
- Operating Temperature: -20°C to +80°C
- Storage Temperature: -40°C to +85°C
- Humidity: 40°C, 90% to 95% for 240 hours
- Libration: 20G’ Max. (10~20Hz)
Custom Membrane Switches
Membrane Switches custom made to your specific needs and desires. We offer a variety of substrates and special features (Options include surface texture materials, embossing, backlighting (Fiber Optic or Electroluminescent), Embedded LEDs, ESD shielding) can be incorporated to accommodate your branding efforts.
Membrane switches can be tactile or non-tactile, depending on the design. Tactile switches provide a physical “click” when the user pushes it. Non-tactile switches have longer lives, but lack physical feedback to the user.
Different types of front materials, lighting options, shielding options, housings, displays and finishing options give you absolute design freedom on your membrane switch application.
Thickness
125 microns, 175 microns, 250 microns, 380 microns and 500 microns etc. Commonly used is 250 microns thickness.
Color
We can do CMYK Full Color Printing Graphic Overlays with UV Digital Printing Machine or UV Offset Printing Machine.
We can print special ink like gold/silver metallic ink, Holographic Ink, Mirror Silver Ink, Mirror Gold Ink, Chrome Silver Ink, Glow in the Dark and Fluorescent Inks. PMS Color.
Finishes
Clear, velvet and embossed. The more common choice is the velvet finish which is excellent for hiding surface scratches.
Texture or selectively textured finishes can be added to the surface of an graphic overlay.
Back Adhesive
Nitto, 3M9448A, 3M467MP, 3M468MP, 3M9080, 3M200MP, 3M200LSE, 3M300LSE, 3MVHB.
Adhesive or selective adhesive can be added for simple application procedures.
Temperature Ranges
Maximum temperature ranges from 60°C (140°F) to 125°C (257°F).
Windows
Clear Windows for Displays or Indicator Lights, Transparent Windows, Adhesive-free Windows, Tinted Windows.
No MOQ and Fast Turnaround. Small orders Prototyping acceptable.
Looking to use a membrane switch for your application and don’t know where to start?
Contact Graphic Overlays China today to learn more about Custom Membrane Switches or get a free quote now.