Most pad printing, isn't, apparently

[Daniel Beardsmore]

Interesting …

http://www.keysourcechina.com/seven-tec ... nting.html

According to this page:

"Pad print is usually used in some high end keyboards"
"Screen printing is the most widely used printing technology in keycap printing. Similar to pad printing, it can also print various colors. To keep the letters from being scratching, uv coating will be added on top of letters."

Then, according to EliteKeyboards:

http://www.elitekeyboards.com/products. ... 104_grn_tw

"Tampo pad printed legends offer better durability than lasered or silkscreen printed legends that come stock on many mechanical keyboards." (Tampo is another name for pad printing)


This apparently explains what I've been wondering about for so long: why do you have decal-look and non-decal-look pad printing? Why do some better laptops have the non-coated printing?

"Decal look" is coated silk-screened—which explains why the lettering is completely flat on the keycap—and the thick, raised printing that Filco use (along with high-end Dell machines, Fujitsu, vintage Nan Tan keyboards and others) is genuine pad printing (it's thick, raised ink).


Can anyone here corroborate this? Does this all seem reasonable and plausible?


(Annoyingly, the page has a different definition of the various laser approaches compared to western companies' terminology.)

[daedalus]

I thought that the non-coated ones were less durable? (See the printing on the black Model M13s, and the minor shitstorm that occured over the printing on Filco keys many years back on Geekhack)

[BlueBär]

Just fyi, Lego uses Tampo Pad printing.

[JesuswasaZombie]

So the decal looking legends are really just screen printing that's been coated? huh.

[Daniel Beardsmore]

I thought that the non-coated ones were less durable? (See the printing on the black Model M13s, and the minor shitstorm that occured over the printing on Filco keys many years back on Geekhack)

That's my perception too — the pad-printed (non-decal) ones are actually pretty durable.

However, we got a laptop in today, where the UV coating was more durable than the keycaps themselves. Seriously. HP Compaq laptop, with the writing standing up untouched on heavily worn-down keycaps. I am not sure what they made the keycaps out of — putty? The wear looks like the final keyboard (the M8 one) on this page, just more severe:

http://atariage.com/forums/topic/105170 ... nts/page-2

The keyboard also has an extra column of keys on the left, ,rsmomh yjsy \i lrr[ yu[omh ;olr yjod :(

[Daniel Beardsmore]

I put this past Robin at Cherry, who disagrees and considers that it's all one printing process.

Now, I looked up pad printing, and there is no silk screen involved.

Moar data needed!

[metalliqaz]

That screen printing with UV coat is used on my cheap-o Dell Quietkey that I bought in college and used for years. It still looks new. I guess they can make it durable as all getout.

[Daniel Beardsmore]

As I understand it, it's owner-dependent. A combination of usage factors (skin oil, typing style etc) contribute to how well the lettering lasts, or how fast it wears. By and large, pad printing lasts for years, but it lacks any guarantee that the lettering won't wear off.

Still no further to determining the truth of these assertions. I'm going to e-mail EK and see if they can find some sources for that information.

[dorkvader]

All plastics will wear, and therefore, no legends guarantee the lettering won't wear out.

Cue image of that medical transcriptionist keyboard (keytronic, I think?) with some keycaps worn through to the stems.

I, myself, have a model M whose legends are starting to fade.

In the long-run, legends are ultimately a losing battle. All you can do is adopt a hard plastic that won't wear as fast (dye-sublimated PBT is an acceptable choice) or adopt a technique that ensures by the time the legend wears, the keycap is useless (double-shot injection molding). All the rest (etching, engraving, printing, etc) is functionally the same with respect to such guarantees, even if they may vary somewhat by timescale.

Nevertheless, I am certainly interested to learn more about this process.

[Daniel Beardsmore]

If you manage to wear doubleshot through far enough that the legend is destroyed, I think you have bigger problems, like possibly sandpaper for skin. You may want to seek medical advice.

[Daniel Beardsmore]

Officially debunked. Finally heard back from EK — the silk-screening mentioned refers to limited batches of aftermarket keys such as Esc and WASD, not to whole keyboards, apparently. Also, none of Devlin, QWERkeys and Signature Plastics are aware of anyone using silk-screen printing for keycaps.

Melissa also pointed out a mistake on that Key Source China page that was lifted verbatim from our wiki without any intercepting grey matter realising that our description of double-shot moulding was a little off (the two plastics aren't "fused together"!)