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geekhack Community => Keyboards => Topic started by: timw4mail on Sun, 09 August 2009, 10:43:15

Title: PTFE Keys?
Post by: timw4mail on Sun, 09 August 2009, 10:43:15

So I've been randomly looking around at different plastics...and I came across
Polytetrafluoroethylene (PTFE)

As described here (http://www.dynalabcorp.com/technical_info_ptfe.asp) PTFE has a high resistance to all know solvents, acids, and oxidizing agents, and is highly resistant to UV weakening.

It would seem that PTFE would be the perfect plastic for keyboard keys, if you overcame it's one weakness for this application: It has one of the lowest know friction coefficients, its very slippery.

While I don't know how well it accepts dye, its high melting point would guarantee no melted keys.

Do you think PTFE has ever been used for keycaps?

Edit:
PTFE is also known as Teflon.

Title: PTFE Keys?
Post by: molto on Sun, 09 August 2009, 10:51:17

PTFE is also very soft, so the keys would be highly susceptible to scratching. It is further relatively heavy and expensive, feels like wax and is self-lubricating.
I don't understand why PTFE has caught your eye because there are many plastics with high chemical resistance.

Title: PTFE Keys?
Post by: timw4mail on Sun, 09 August 2009, 10:58:58

Quote from: molto;108400

PTFE is also very soft, so the keys would be highly susceptible to scratches. It is also relatively heavy and expensive.
I don't understand why PTFE has caught your eye because there are many plastics with high chemical resistance.

But none to the degree of PTFE. I never claimed it was practical, just was kind of contemplating it.

Title: PTFE Keys?
Post by: keyb_gr on Sun, 09 August 2009, 11:08:04

Teflon is used for mouse feet just because it has very low friction. You'd have a hard time trying to make it stick on keyswitch stems. And yes, it is pretty soft, which is why teflon coated pans (another application exploting the low friction) don't last forever.

Title: PTFE Keys?
Post by: huha on Sun, 09 August 2009, 14:32:42

PTFE is relatively expensive. Also, what good is chemical and UV resistance for keycaps? The only property you'll want for keycaps is durability, i.e. some resistance to acids to resist being dissolved by sweat (but most plastics happen to have this property anyway) and very hard material so it's not ablated by constant and repeated movement.

Better plastics are POM and PBT; they're quite hard and therefore not very prone to becoming shiny and losing texture.
Incidentally, Cherry use them for their keycaps.

-huha