how do I print opaque black background for backlit signs

dasigndr

New Member
Hello All,
I am thinking this has probably been addressed but I can't find anything on it.

I often need to print a backlit sign (typically onto vinyl and then mounted to plexi face) with a black background.
The other graphic can occasionally be text copy or even a full color image and at times a gradient image that flows into the OPAQUE black background.

I am running Onyx poster shop 11.1.2.103
and am printing with my latex HP110

what settings should I be using/adjusting to get the OPAQUE BLACK background?

I have tried so many and can't get it completely opaque black.

HELP!!!
 

MikePro

Member
the term you would be looking for is dual-layer printing for illuminated prints: same image printed, applied with a white diffuser between, will illuminate/blockout as designed. done via clear print mounted on white trans substrate with mirror-printed image applied to backside OR white trans. print applied laminated onto clear print and mounted/applied to transluscent substrate OR having a flatbed printer that prints white, white allows you to layer your print (image>whitelayer>image) on one surface.

else, yeah...if you want to just print black in one layer, just make a really dense black with 100K and 20-30CMY depending on your ink limits. but then your gradient will look washed-out into a hard-line of your black when illuminated.
 

P Wagner

Member
Hello All,
I am thinking this has probably been addressed but I can't find anything on it.

I often need to print a backlit sign (typically onto vinyl and then mounted to plexi face) with a black background.
The other graphic can occasionally be text copy or even a full color image and at times a gradient image that flows into the OPAQUE black background.

I am running Onyx poster shop 11.1.2.103
and am printing with my latex HP110

what settings should I be using/adjusting to get the OPAQUE BLACK background?

I have tried so many and can't get it completely opaque black.
HELP!!!

Good suggestions in this thread.

The issue is getting enough ink onto the media to remain opaque when backlit. That has everything to do with the amount of ink being deposited (ink density) in the print mode being used. Standard print modes for frontlit opaque medias are typically in the 100 percent density range, but for backlit applications, 150 percent ink or higher are required. It also depends on whether the media is translucent white or clear.

There is a Media Preset for the Latex 110 on the HP Media Locator for 3M 8150C that uses 150 percent ink density:
https://www.printos.com/ml/#/medialocator

There are other media presets that offer higher ink densities as well.
 

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Dan360

Member
That would be a lot of steps. Easiest thing to do is to get a profile from the media locator and tune it to your material.
 

JBurton

Signtologist
I usually plot black to lay over the black areas if I want a true opaque black. Depending on the sign, this can cost more than the print, but you can tell the difference between a true opaque next to a printed layered opaque black when lit.
 

unclebun

Active Member
You can increase ink limits and ink density or double strike all you want and light will still come through it. A double layer print is better, but if it has to truly block all light you need to plotter cut black vinyl and apply it to the backside of the face.
 

Andy D

Active Member
Putting enough ink down to make it truly opaque is problematic & could cause vinyl and/or lamination failure.
As @JBurton said, print - laminate - mount - apply black cut vinyl -or-
Print one layer normally and another of only the black.
 
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It's also good to manage expectations with your client - if they're expecting a true opaque black-out, printing can really only go so far unless you're either layering the print or using cut vinyl made for that purpose. The layering is super helpful for gradients or other complex printed logos. It's also one of my least favourite projects :p

Back when I had just started in this shop, the team had to re-do a large black sign because even though it was printed at like 100/50/50/50 and all the "right" settings, it wasn't opaque enough for our client (understandably - it wasn't really that opaque). Shop thought it would save work by just printing instead of plotting, but here we were doing it a second time.
 
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JBurton

Signtologist
It's also one of my least favourite projects :p
If you are trying to float a clear print over another print (Yes the better way is trans white over clear for less saturation during daylight hours, but loading the printer twice substantially increases the already extra costly face), make sure to stretch the first print a little as you are sticking it. The second layer will always be bigger than the first, and it's really impossible to get it to line up once stretched. Also, laminate both prints so they are both stretched on the laminator. We double layer everything that is lit, and unless it is a particular color the client needs, we just opt for two layers of clear on the face rather than one mirror on the back or a trans white over the clear. Makes colors rich and satisfies most clients.
Also good point, some folks can live with a dirty brown set of lettering when lit, others expect a full black background after dark so their lettering really pops, it's all about figuring it out before it leaves sales and enters production.
 
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