Printing recommendations for applying foil on top of UV prints

[HGdesign]

Hello, hope you are all doing well.
I'm printing various projects on a Mimaki UCJV300 series printer and am interested in trying to apply foil on TOP of prints. I am aware that I can simply print over metallic media and just use the opacity of the ink to selectively cover & reveal areas that are metallic. I am already using this technique for some projects and not asking about that. I am specifically interested on the process to selectively apply foil on TOP of a print. I belive the area to be foiled needs to be "under-cured" during printing. This creates different finished effects with the ability to have some areas that are a bit of raised texture to them due to the ink build up and allows for foil on top of media types other than metallics. For example we need to do this on some clear media, and craft papers, etc. where it is not possible to begin with a roll of metallic media.
- I would like to learn more from those of you have tired this approach and understand what techniques and settings need to be used to create various effects.
- I believe the area to be foiled has to be under-cured during the uv process, but was not able to find details on what are the actual recommended machine settings
- I am thinking we will have to pull-back and print the foilable areas, open to suggestions & tips
- Can any of the CMYK, and or WW inks be used for the under-cured foible areas, or does it absolutely require GL ? Curious if you've tried it and seen the results without using GL?
( I currently have LcLmWW on head 2. Plan to switch it to GlGlWW at some point, but have not done that yet)
- Any health concerns with under-cured inks? I belive the inks become safe for handling once cured, but you don't want skin exposure when wet. Curious if you have experience with how "under-cured" it is for this process, and does it cure over time on its own after its foiled
- Any sticky issues where a stack of prints ends up stuck to each other from storage
- I am thinking the foiling is done cold with simply pressure, or does it require heat as well?
Thank you all so much for sharing your experiences!

 

[SlikGRFX]

When commercial printers apply foil to paper they normally print a heat activated resin. The prints then pass through a foiling machine that rolls the foil onto the print with heat and pressure and the foil sticks only to the resin. Never heard of this done with a wide format UV printer but I’m interested to know if it’s possible. Although I can’t imagine how uncured ink would work. Uncured ink is essentially liquid so it would run or bleed and lose detail.

 

[HGdesign]

When commercial printers apply foil to paper they normally print a heat activated resin. The prints then pass through a foiling machine that rolls the foil onto the print with heat and pressure and the foil sticks only to the resin. Never heard of this done with a wide format UV printer but I’m interested to know if it’s possible. Although I can’t imagine how uncured ink would work. Uncured ink is essentially liquid so it would run or bleed and lose detail.

You are correct, but from what I understand, there is an approach to modify the UV lamp settings to partially cure the ink. It is not left in liquid form, but not 100% cured either. My guess is something like 90% cured. The goal is to leave it just tacky enough to be sticky, so it bonds to the foil when it is pressed on. I think it can be pressed cold thru a laminator, but I can't find enough info as to the settings and exact best practices. Hopeful that someone who has successfully done it can help out with the steps needed to achieve it.