Straight after the meeting with Luke we ventured back to college excited to experiment with the technique Luke had shared with us to create a scratch overlay, it basically allows us to print over designs but scratch away to reveal a design, just like a scratch card.
First of all we mixed together an metallic printing ink using binder and silver metallic flakes, unfortunately they'd run out of silver so we had to use a pearl silver that was a lot lighter and more translucent than the silver flakes.
We then add a small amount of washing up liquid to the mixture to make it easier to scratch off (Luke didn't go too much into the technical details of the washing up liquid). We just used the bog standard ordinary liquid they have in the print room.
It changes the viscosity of the ink to a runnier mixture but without affecting the translucency of it. This aids the printing and scratching process but not so much the drying process because it takes a lot longer due to the oils and viscosity.
For the scratch offs to work we have to print on to a highly gloss none absorbent surface so that it can be scratched off without leaving a mark underneath. We used this clear gloss adhesive sheets we purchased from a craft store that are thin enough they're only really noticeable when the light shines on them as you can see below.
We proceeded to mask off the gloss so that none of the ink would actually go on our paper and leave an unscratchable silver box around the scratched off area, but because of the viscosity of the ink we couldn't be sure there would be no bleeding.
As a double precaution we masked off the screen as well, this wasn't perfectly masked but masked enough that the ink would just run over the masking tape and not the surround paper, because it was our first time and experiment, it was all a learning process for us so we were delving into the unknown even though we'd screen printed before.
We used a blank screen as we were just experimenting and printing in block colours so exposing a screen would be a waste of time and effort.
as you can see only the mask and gloss sheet is revealed through the screen
These two images just illustrate the printing process which is pretty standard printing so there wasn't too much to document. What I did notice was because of the washing up liquid, pulling the screen was a lot easier and because of the fact we were printing onto gloss we couldn't pull too many times or else there would be large amounts of surface ink.
