Terminology
| Actuation Force: |
The force required to collapse the web of a rubber keypad in conjunction with
polydome, metal dome, mechanical switch or rubber only. |
| Air Channel: |
Air path(s) on the bottom of rubber keypads that allows for air passage when rubber is
depressed. |
| Alignment Hole: |
Through hole in rubber keypad that is used to position keypad in enclosure. |
| Base Matte: |
Silicone sheet material that joins all keys on a rubber keypad. Also known as mat. |
| Bezel: |
The faceplate or cover, typically plastic or metal, used to secure a keypad to a
printed circuit board or switch. |
| Bosses: |
Small posts used for positive alignment of rubber keypad in bezels or assemblies. |
| Compression Set: |
The measurement of a material's ability to recover its original size and shape after
compression under prescribed conditions. |
| Conductive Rubber: |
Silicone keypad impregnated/coated with conductive material. |
| Color Matching: |
The visual and electronic analysis of a mixed silicone rubber material compared to a
supplied color sample. |
| Diaphragm / Web: |
The thin hinged area that permits a rubber key to flex. |
| Durometer: |
A measurement range of hardness for silicone rubber. |
| Key Height: |
The measured distance from the bottom of a keypad (base matte) to the top surface of a
key. |
| Legend: |
Printed graphic (symbol, letter or number) on the top of the rubber surface. |
| Life: |
The number of actuations realized before the rubber diaphragm/web ruptures. |
| Reversed-Out Graphics: |
Graphics that allow rubber color or masking color to be seen through top surface
printing on keypad. |
| Positive-image Graphics: |
Single or multi-color printing on top of key surface. |
| Snap Ratio (A-C)/A: |
See graph |
| Stroke / Travel: |
Distance from the contact surface of a rubber part to a surface. |
| Swell: |
The increase in volume of rubber when in contact with petrochemicals for a determined
period. |
| Tactile Feel: |
The response of rubber while depressing. For tactile rubber keypads, it is a critical
function of the diaphragm web geometry. |
| Tear Strength: |
The tear strength is a measure of the resistance of rubber to tear forces. The tear
strength is calculated by dividing the maximum force load by the thickness of the rubber. |
| Wear or abrasion resistance: |
The resistance of a particular ink or coating to manual wearing. The testing process
is usually a Norman tester with the number of cycles legends can perform before wear is
noticeable. |
