Graphic Overlay For Capacitive Touch Buttons on a PCB

Projects General Guidance
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I have purchased a capacitive touch panel from Sparkfun SparkFun Capacitive Touch Keypad - MPR121 - SEN-12017 - SparkFun Electronics and would like to find a plastic sheet that I could print with a laser or inkjet printer to use as an overlay for this panel. Ideally, the sheet would have an adhesive on the back side, otherwise I would use glue that is acceptable to that application. The overlay would have outlines and identifiers for the tough pads.

I have googled and looked on ebay and have been unable to find an appropriate material. I imagine there is sheet material out there that is appropriate but I am probably not using the correct search terms. So any help here would be great.

Thanks
wade

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Look up "water slide decal". It's an extremely thin type of clear plastic that uses a water soluble adhesive.

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Thank you for the two responses, I appreciate them.

I should have included in my original post that I need a solid sheet not a transparent one as I want the solid color of the sheet to fully cover up the PCB. In addition I should have included that this is for an outside un protected location for water soluble glue might not work the best.

Thanks Again,
wade

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I need a solid sheet not a transparent one

Cover the entire sheet with ink. (i.e. set a background color before you print).

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Well... inkjet printable vinyl sticker with a laminating clear sheet applied might be what you need. You need to make sure and get an inkjet printable vinyl that is compatible with your printer. IE, compatible with water based inkjet inks.

Make sure the ink is fully dry before laminating. It will seem dry to the touch, but in fact it may take a week to really fully dry. Pigmented inks will last a -lot- longer in the sun than dye inks. Both of these tips are from personal experience.

That is one of the ways that I make overlays for touchpanels.

I don't see a country....

http://www.papilio.com/inkjet%20waterproof%20adhesive%20film%20media.html

Note that they recommend Epson Durabrite, because it is pigmented ink, and lamination to increase the outdoor life. Lamination also completely removes the problem of the graphics wearing off due to handling.

http://www.justforcrafters.com/store/pc/viewPrd.asp?idproduct=1542

Also note that not all inkjet printable vinyl is suited to hot lamination, and may require cold lamination, such as the one above. Even with the vinyl made for hot lamination, I keep the temperature down and use thin 1.5mil laminate, unless it is something that is going to take a lot of abuse.

You may also find it as inkjet bumpersticker. Craft stores that sell supplies for the CriCut should carry the CriCut inkjet printable vinyl stickers, too.

I hope this helps. One of the features of this is that LEDs shine right through it.

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Why not put the graphic underneath the touch sensor? (I presume it is transparemt)

...R

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The touch sensor is a PCB with copper pads on it.

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polymorph:
Well... inkjet printable vinyl sticker with a laminating clear sheet applied might be what you need. You need to make sure and get an inkjet printable vinyl that is compatible with your printer. IE, compatible with water based inkjet inks.

http://www.papilio.com/inkjet%20waterproof%20adhesive%20film%20media.html

This is exactly the route I decided to try I ordered the vinyl and clear oversheet from papilio, I placed the order about an hour before your post. I will keep people aware of the progress.

Thanks to all who read and to those that responded with ideas.

wade

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pcbmaking.com would be the best option for printed circuit board. It designs professional PCB at cheaper price. You can place your order instantly and get free shipping. Its easy way to get your job done! Good luck!
PCB DESIGN

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What does that have to do with graphic overlays?