Choosing the right membrane switch can be a challenge. There are so many questions, like:
- Which material should I use if I need certain graphics printed on my switch?
- Which coatings should I apply on switches made for outdoor use?
- What’s the most efficient membrane switch design for my product?
We’re going to answer all of these questions—and many more—in this guide:
Types of membrane switches
Broadly speaking, membrane switches can be grouped into two categories: Tactical and non-tactile.
Tactile membrane switches
Tactile membrane switches offer tactile feedback in response to being activated by finger or actuator. This tactile feedback improves the user experience in scenarios where other types of feedback are limited or where it’s critical to confirm that the switch has been pressed.
In other words, tactile membrane switches are used when other types of feedback (auditory and visual) are insufficient or unacceptable as forms of feedback. Some tactile membrane switches will feature auditory, visual, and tactile cues.
These membrane switches are common throughout a number of industries. Some of the industries that put a high value on tactile feedback include:
- Consumer electronics
They’re also essential in any hazardous environment where it’s imperative to confirm that a switch has been activated or deactivated.
Our tactical membrane switches are built using metal dome arrays; these small arrays (8 mm to 20 mm) offer up to 1 million+ use cycles. In most circumstances, they’ll outlast the other parts of the product you’re building.
Non-tactile membrane switches
Non-tactile membrane switches are simply membrane switches without tactile feedback. They offer feedback in other ways (such as auditory and visual feedback).
These membrane switches are more affordable than their tactile cousins. Their design is comparatively simple, and a slightly sleeker profile can be achieved by omitting metal domes. As such, they are often preferred when:
- The membrane switch must be extremely thin
- The OEM is trying to limit the cost of parts
Non-tactile switches are used in almost every industry, from agriculture to transportation.
Which overlay material is best for my application?
Graphic overlays play two important roles in the overall construction of a membrane switch:
- They protect the underlying components of the switch from damage and contamination from dust, moisture, UV rays, and other risks.
- They provide a surface on which graphics can be applied. These graphics can be critical to the use of the membrane switch (icons and instructions) and supply branding and aesthetic appeal (logos, colors, and the like).
There are a number of different materials that can be used for graphic overlays. Below, we’ll detail two of the most common: Polyester and polycarbonate.
Polyester for membrane switch overlays
Polyester (PET) carries a number of advantages for graphic overlay applications. These advantages include:
- Robustness and chemical resistance
- A long lifecycle (1 million+ uses)
- Excellent clarity
- Lightweight and flexible
- Fatigue resistant
- Abrasion resistant
The combination of durability and flexibility makes polyester an excellent choice for consumer electronics, medical devices, and other devices that are used frequently.
While polyester is the more difficult material to print, emboss and die cut vs polycarbonate, an experienced ISO 9001 supplier will have the necessary manufacturing experience and process control systems in place to deliver quality polyester overlays.
Hard coating can also be added to enhance the strength and durability of a polyester overlay. Appearance-wise, polyester overlays can offer consistently textured, glossed surface, brushed surface, and antimicrobial coatings.
Polycarbonate for membrane switch overlays
Polycarbonate (PC) is generally recommended for applications with lower flex requirements, as the material has an expected life of 100,000 actuations. General Label suggests using Polycarbonate in non embossed overlays as embossing will shorten life cycle
PC offers several visual and production advantages. The material is easier to print on (including color matching) and die-cut than PET. Polycarbonate comes in a broader range of thicknesses, texture, and finishes. So, if aesthetics are more important to your application than durability, polycarbonate would be a good lower cost option to polyester.
Polycarbonate can be flame resistant which may be important in certain industries. Typical UL rating on flame resistant PC is 94 V-0
Choosing the right material for your project
There are a wide variety of considerations, including where the final product will be used, how often you expect the membrane switch to be utilized over the life of the product, the complexity of the graphics, and more.
Generally, polyester will be the choice for projects with large, complex graphics and for projects where over a million uses can be expected. Polycarbonate, on the other hand, is commonly used for products that will be used outdoors and for OEMs looking to limit costs.
It’s important to remember that a wide variety of coatings can be utilized to improve and customize any materials used for your graphic overlay. Display windows, selective texturing, and other features can also be integrated.
Questions you need to ask
How big does the switch need to be?
We can create a variety of sizes and shapes, and there are a variety of techniques that can be used to reduce the size of a membrane switch. For example, a printed circuit layer can be designed with a matrix layout to reduce its size. Small, side-fired modern LED lights can also be employed to reduce thickness, maintaining your membrane switch’s sleek profile.
Where will the switch be used?
The environment your final product will be used in plays an important role in the design of the membrane switch. Membrane switches used outdoors, for example, will need to be built using UV-protected material and coatings. Other membrane switches may need to be designed to protect against electrostatic discharge (ESD). Talk to us about the typical environment your product will be used in!
What industry-specific considerations need to be applied?
Many industries rely on ingress protection to keep their equipment running and to keep users safe. This is especially common in the medical industry. We offer switches built in clean rooms with up to IP67 protection.
Do you need any form of backlighting?
Backlighting helps users interact with your product even in low-light scenarios—it’s key in building products from consumer electronics to military equipment. Our sleek, low-profile LEDs offer backlighting without dramatically increasing the profile of your membrane switch.
Is tactile feedback required?
Where tactile feedback is required, stainless steel dome arrays can be used. These domes are thin, durable, and offer easy-to-detect tactile feedback. A tactile membrane switch doesn’t require a lot of force to activate, but the tactile feedback confirms that the membrane switch has been activated (or deactivated). This makes them a great choice for many medical devices made for consumers.
Are there any shielding requirements?
ESD shielding, UV shielding, shielding against corrosion and chemicals—there’s almost no end to the number of protective coatings we can apply to a membrane switch.
Is a bezel or back plate involved?
When bezels or back plates are involved, it’s usually easiest to add as a part of the membrane switch manufacturing process. Let us know in advance!
Choose the right membrane switch with General Label
Need a membrane switch? Call us—we’ll help you avoid bulky switches by creating an efficient membrane switch with a sleek, perfectly-fitted profile. Your final membrane switch design will be perfect for your product—we guarantee it.