Membrane Switch FAQ

Descriptions for some common questions in the design of membrane switch, such as the graphic design,
circuit design, keys type, ,...etc, This can be more suitable for JRPanel manufacturing capability.

METAL DOME ( USED AS KEYS)

In the membrane switch, the metal domes are used as the upper circuit layer, when pressing, the circuit is connected to the lower circuit, which
plays as a role of the switching function. It is made of ultra-thin stainless steel ( 0.05mm - 0. 1mm thickness ), and stamped by 5~7 processes such
as die ( ultra-cryogenic processing ) and optical grinding. It is flexible and can be pressed more than one million times. It is mainly used in membrane
switches. It has four advantages: strong continuity, stable rebound, excellent feel, and long life.

 

The usage of metal dome:

1. With the aid of the conductivity of the metal, connect the two pole contacts of the switch.

2. With the rebound of the metal dome, it can provide tactile feedback to the operator.

 

According to the shape, there are mainly 3 kinds: Circle dome, Triangle dome and Four-legs dome. JRPanel uses the stainless steel Four-legs dome.
The available specifications are 8.4, 10, 12, 14, 16mm in our site. The choice of metal dome should be larger rather than small. When possible, it is
better to use larger metal dome, but It also needs to be considered suitable for the actual product.The metal dome size of 10-12mm is generally
recommended, which is more suitable for actual finger pressing.

Five size are available
Rebounding Force 280g

  • 8.4
  • 10
  • 12
  • 14
  • 16
mm
DIE PRESSING ( KEYS TYPE)

Another type of membrane switch button, it is an embossed silver pad in the circuit layer by the "embossing" process, the silver pad of the button as the upper circuit is pressed into a fixed spherical crown shape with a mold, so that the button position of the entire switch has a guiding effect, and the material has a certain elasticity which is generated after the deformation by embossing. Also the button will rebound after being pressed, so that the button has a good touch feeling. The operator can obviously feel the closing of the switch.

 

 

 

It is also contact with the lower circuit to achieve circuit conduction through pressing. The convexity of the die-pressing needs to use the mold, especially for the batch order, which convexity mold needs to be specially customized. This can greatly improve the production efficiency and the stability of the product quality.

 

The size of the die-pressing can be designed to be 5mm-11mm, JRPanel recommended size is 8-10mm. The button size will be more suitable for finger pressing.

CABLE SPACING OF TAIL CABLE (CONNECTOR)

1.0mm pitch tail reinforcement (partial enlarged view)

2.54mm
Female Housing Terminal
2.54mm Male Terminal
(No housing)
2.54mm Female Terminal
(No housing)
2.54mm Cable
No Terminal
1.0mm Pitch
1.27mm Pitch
LED COLORS & DESIGN DESCRIPTION

According to the design requirements, LEDs can be mounted on the circuit of the membrane switch, and the LED light can indicate the function of product operation and button selection. JRPanel can provide a variety of high-quality LED colors, ( Package: 1206 ), SMD Type, the recommended diameter of LED window is about 3-4mm.

 

Monochrome LED Colors: Red, Yellow, Blue, Emerald-Green, Yellow-Green

Bi-Color LED: Red + Emerald-Green

RGB LED:Red + Emerald-Green + Blue

Reminder: Please be sure to indicate the LED color and the directions of LED ( the polarities (+/-) in the design drawings . (Following is an example picture, please refer to the actual product)

(Monochromatic LED) Package 1206

  • Monochrome LED
Bi-Color LED

Emerald-Green
+Red

Pic 2 Bi-Color LED & Circuit Design Refer

RGB LED

Emerald-Green
+Blue
+Red

Pic 3 RGB LED & Circuit Design Refer

3M ADHESIVE TYPE & DESCRIPTION

- 3M GENUINE QUALITY ASSURANCE -

3M Adhesive Type #
Substrate Thickness Color Temp. Range Adhesion

3M55236

- Cheapest -
Non-woven cottonpaper adhesive 0.12mm Translucent 90°C (LT) ~ 120°C (ST) 11.5N/10mm
General used double-sided tapewith durability, Good temperature resistance and strong adhesion,
Recommended for regular indoor use. ( Couldn't be repeated used that the glue will be broken )

3M9448A

Non-woven cottonpaper adhesive 0.15mm Translucent 70℃(LT)~150℃(ST) 14N/10mm
Good initial viscosity and easy die cutting. For plastic, rubber, rough surfaces, All have good adhesion;
Good adhesion at high temperatures ( Couldn't be repeated used that the glue will be broken )

3M467MP

- Thinnest -
Substrate-free pure adhesive 0.05mm Transparent 149℃(LT)~204℃(ST) 5.5N/10mm
Excellent bonding effect, Can prevent shedding and excellent waterproof , Good process-ability, Better holding power, The product is resistant to high temperature, super sticky and no residual glue. ( Couldn't be repeated used)

3M468MP

Substrate-free pure adhesive 0.13mm Transparent 149℃(LT)~232℃(ST) 8.5N/10mm
The thickened type of 3M467MP, Excellent bonding effect,Can prevent falling off with waterproof performance, Good process-ability, good temperature resistance, and good adhesion;The release paper is polymer-coated waterproof kraft paper, Will not wrinkle in high humidity environment, good temperature resistance.( Couldn't be repeated used)

3M300LSE

Best
Waterproof
Substrate-free pure adhesive 0.17mm Transparent 93℃(LT)~149℃(ST) 9N/10mm
Excellent waterproof performance, Good temperature resistance Strong holding power; High physical and chemical stability, It can insulate humid gas and have a sealing effect, Solvent resistance, Anti-ultraviolet rays, Resistant to rapid temperature changes. Good die-cutting process-ability.Provides excellent adhesion to surfaces such as glass, plastic, polypropylene, powder spray paint and oil pollution.

JRPANEL FIRMLY SELECTED 3M IMPORTED GENUINE ADHESIVE!

ADHESIVE USE GUIDE

  • 1 Avoid touching the rubber surface
    ( glue parts ) with your fingers.
  • 2 Keep the adhesive surface dry
  • 3 Keep the adhesive surface clean
    (Oil-free, no dust, no lubricant separating agent)
  • 4 Apply appropriate pressure
  • 5 Avoid distortion of parts to be glued
    (Note that the parts match each other well)
ESD TYPE

For the 2.54mm pitch terminal, it is ok to do with 3 types ESD : A, B, C.

For the 1mm/1.27mm pitch, it only can do with Type A.

2.54mm Pitch with terminal
Type A
ESD Separate Tail
Type B
ESD tail be combined into cable connector.
( Use common GND line )
Type C
ESD tail be combined into cable connector.
( Not use common GND line )
1mm/1.27mm Pitch
Type A
ESD Separate Tail
The use of ESD layer:

In order to prevent the surface of the membrane switch from being charged with static electricity, JRPanel can add a layer of conductive adhesive or an independent shielding layer to the membrane switch and lead out the ground line. The main principle is to use electromagnetic shielding to shield space electromagnetic interference, thereby reducing and eliminating electromagnetic interference from space. After adding the electrostatic shielding layer, the overall structure of the membrane switch will become thicker, which is not suitable for products with higher thinness requirements;

 

There are three types of lead design for electrostatic nets:

you can choose the appropriate type according to actual needs. When placing an order, please note the required type.

EMBOSSED TYPES OF KEY / BUTTON

For membrane switch and Graphic overlay, there usually will do embossing for the keys, which can help the operator to quickly determine the position of the button, make the button feeling better, and also make the product more design and three-dimensional.

The key embossing is to do embossed for the key area with a drum press on the graphic layer. This method has strict temperature and pressure requirements based on the natural and convex-concave characteristics of the material.

 

It has the following advantages: (1) Improve the decorative effect of the appearance of the membrane switch. (2) The operator's sense of touch is relatively sensitive. (3) The range of the key body is accurately given. (4) Improve the recognition speed.

 

JRPanel provides a variety of embossing types, which can reach customer's requirements with different types of keys. Circle Embossed, Flat- Embossed Key, Edge- Embossed, Key Shape Embossed, Flat- Key ( No embossed ).

 

Following are 2 reminds: 1. The default key type is the circle embossed ( the first on the left) ), If need to do with other kinds embossed type, kindly pls noted in the remarks or drawings when placing the order. 2. when designing embossing, please design the corner of rounded corners, It couldn't do not sharp corners ( this will break the graphic layer )

  • Circle Embossed

  • Flat-Embossed Key

  • Edge-Embossed

  • Key-Shape Embossed

  • Flat-Key
    (No embossed)

MATERIAL SURFACE TYPE ( GLOSSY / MATTE )

Graphic Layer Material:

It is mainly choose PC/PET material.

 

According to its surface type,
it can be divided into:

① Matte surface ( translucent film )

② Glossy surface ( transparent film )

If you need a smooth window, other surface matte,
JRPanel can also provides an option:
"Glossy window with Matte surface"
This can achieve the window glossy and the
effect of other surface matte.

Surface Effect Matte Material

Glossy Material with Matte oil covered

Comparison of Colorless Glossy Transparent Window & Colorless Matte Translucent Window

Distance 20mm - Display Effect

Colorless Glossy Transparent Window

Colorless Matte Translucent Window

No distance - Display Effect

Colorless Glossy Transparent Window

Colorless Matte Translucent Window

For the Graphic layer material, it is to be selected according to the actual use and environment.
LCD display, choose glossy surface;
Digital Tube, it is recommended to use matte surface.
The LED window can be glossy surface or matte surface. But matte surface is recommended, the effect is better, not very dazzling.
MEMBRANE SWITCH THICKNESS

The total thickness of the product depends on the thickness of the material & the type of adhesive, etc. These can be selected by the customer when placing the order. You can check the thickness of the material and adhesive on JRPanel online quoting page conveniently. Quote Now

CUSTOM MEMBRANE SWITCH STRUCTURES
For the membrane switch, commonly has 6-layers structure, see following picture shown:
JRPanel can also support the customization of other special layers, such as 3-layers (Graphic layer, Spacer, Adhesive),..etc . Kindly pls note when ordering.
  • Graphic Overlay
  • Upper Adhesive
  • Upper Circuit
  • The Spacer
  • Lower Circuit
  • Back Adhesive
NOTES ON GRAPHIC DESIGN OF GRAPHIC LAYER
Main design specifications for Graphic overlay

In the membrane switch, the design of the graphic overlay is mainly graphic design, because JRPanel use the silkscreen printing to make the graphic overlay. In the graphic design, the minimum process capability of the actual silkscreen printing process must be considered.
In order to be more suitable for factory production and improve the speed of product completion. When designing the drawing of the graphic overlay, please refer to the following parameters:

Outline tolerance: ±0.2mm【Outline do Lower tolerance as default; Cutout do upper tolerance as default 】 Key border line ≥0.3mm
(Adjacenting Color border ≥ 0.5mm)
Min.Text/pattern line width: ≥0.2mm Embossed key spacing ≥2mm
Min.Silver track width ≥0.5mm Safety distance between outline /cutout to silver track: ≥0.7mm
Max. Panel size: 800*400mm Tail-exit to the edge: ≥0.7mm
Better not design to close to edge. If requirement of waterproof, it need ≥5mm
Embossing height 0.3~0.8mm
About Add Edge Border【Generally choose a dark color】

JRPanel uses silkscreen printing to produce patterns and texts of the membrane switch & graphic overlay. When designing, there will encounter adjacent colors. In the following two situations, it need to consider drawing borders to make the product more suitable for silkscreen printing and obtain better screen printing effects.
(1) When two colors and multiple colors are adjacent to each other, they may be misaligned or shifted because they are printed separately.
It needs to add a dark outline to cover the uneven edges.
(2) Sometimes the colors are mixed when the colors are adjacent to each other, there will be a mixed-color between the 2 colors.
So it also need to add a dark stroke to cover the color line.

① adjacenting colors may be misaligned
It need to add a edge border to cover the uneven edges.
②Some adjacenting colors may be mixed
It need to add an edge border to cover the mixed line.
Light background: Because the light background needs to be printed one more time in order to get a good graphic effect, additional charges are required. For details, please check at link with : Light Background Description

<20% Gray, It need choose the "Light Color Background", as it need do 2 times printing for this color.

10% Gray

>=20% Gray, It doesn't need choose the "Light Color Background"

10% Gray
Color Numbers: JRPanel can make according to Pantone Formula Guide ( Solid Coated & Solid Uncoated ), RAL-K7 CLASSIC,CMYK (May have much difference) and sample (this color is the closest). Please note the Pantone color numbers or CMYK value in the design, and better to send us the samples if have high requirement for the colors ( that be more closest to previous products.)
For the Pantone color numbers, it can be tracked on the Pantone website.
You can check and find the PANTONE numbers in website: https://www.pantone.com/color-finder
ABOUT SILKSCREEN PRINTING

Silkscreen printing refers to the use of a silkscreen frame as the base, and use the method of film exposure to make a screen printing plate with graphics. When printing, the ink can be printed on the substrate through the fine holes of the screen. For the non-graphic area, the fine holes of the screen are blocked, then the ink cannot pass through the screen. Finally, it will print the graphic of customer needed on the substrate material, such as PC / PET. This is the basic principle of silkscreen printing. During printing, firstly, Pouring the ink on one end of the screen printing plate, then applying a certain pressure to the ink portion on the screen printing plate with a scraper, and moving at a constant speed toward the other end of the screen printing plate. The ink is moved by the scraper from the graphic during the movement part of the mesh is squeezed onto the substrate to produce the graphic design that the customer needs

Advantages of silkscreen printing:

Silkscreen Printing

Screen printing with exquisite
Patterns and text

Graphic Overlay

Thickness≤1mm
PET/PC Colorless Film

ABOUT WHITE AND WHITE TRANSLUCENT

In the design of membrane switches/graphic overlay , some customers will design white semi-transparent windows and white patterns & characters in 1 design, but only submit one color when ordering. This calculation is not correct. For white color, it is printed with conventional white ink, and For white semi-transparent color, it need to blend white ink and varnish into a white semi-transparent ink, which can be finally achieve a semi-transparent effect when printing. So the two inks are different and need to be printed separately. Therefore, when calculating the number of colors, it cannot be counted as 1color, but 2 colors. Hope this can be clearly for customer to understand this.

 

In the membrane switch design, if there is an LED design below, the LED window is designed to be white translucent, which can weaken the LED light and make the LED light relatively soft.

 

Metal Dome Die Pressing ( keys type) Cable Spacing Of Tail Cable LED Colors & Design Description 3M Adhesive Type Description ESD Type Embossed Types of Key / Button Material Surface Type ( Glossy 1 Matte) Membrane Switch Thickness Custom Membrane Switch Structures Notes on Graphic Design of Graphic layer About Silkscreen Printing About White and White Translucent TOP