Mutoh UH ink outdoor durability

[Gary Wiant]

I'm wondering what type of outdoor durability everyone is finding with their Mutoh UH inks, specifically on aluminum signs with the XPJ661 UF.

I live the Northwestern Pennsylvania for climate information

 

[garyroy]

Outside printer ink durability is a rabbit hole.
Have you ever driven down an interstate and seen a field full of 45-degree panels facing the sun?
When you look back you see hundreds of 1 ft sq paint samples in hundreds of different colors. That's the paint company's trying
to determine the outdoor life of their paint. They leave them out there for years and then compare it to original swatches to test fading and durability.
Maybe a more modern test now would be using 24 hour indoor UV lighting to accelerate the process to weeks, not years.

Trying to figure out which printer ink, on what material, with which laminate (or not), in which environment, facing in what direction, for what period of time,
under what weather conditions, is a fool's errand. How could anyone ever do it. By the time it's figured out for your particular location and situation, the
company comes out with a different printer with a different ink set.

It's funny but a customer will go out to dinner with their mate and in laws. They'll spend $400 on a really nice dinner.
Ask that same customer to pay $400 for a sign that will advertise their business and make them thousands, may tens of thousands of dollars over a period of
many years, and they throw themselves on the ground and have a hissy fit: go figure.

Sorry to say, when the sign wears out, it wears out, whether it's from sun, rain, or any other variable. The customer just has to buck up and buy another one.
Same with printers, same with cars, same with shoelaces. In some cases, they last really long, in other cases they wear out quickly.
From what I've read "Outside durability is 3 to 5 years"

 

[Gary Wiant]

Ok thank you 3-5 years is what I was looking for

Gary

 

[Joe House]

Only slightly related, but be aware that Mutoh has let its distributors know that they will only guarantee ink with 2 months shelf life left on their UH21 and VJ-US11 inks. So, distributors will have to reduce their stock levels on the shelf and you may be getting ink that needs to be used faster than you expect - or possibly faster than you can use it.
I can't think how this will affect outdoor durability, but I've seen it play heck with clogging nozzles.

Good Luck

 

[chrisphilipps]

The Mutoh UV ink isn't rated for 3 to 5 years, that is their eco-solvent inks. Depending on the ink type and the material used, 6 months to 1.5 years is the all you would get.

 

[Ronny Axelsson]

I started making some print samples with VJ-626UF when I first bought it three years ago, to see how colors would fade over time.
These were put on a wall facing south, but I suspect my conditions here in southern Sweden can't be compared to Pennsylvania (should be more like Spain or Italy I guess).
Anyway, my tests shows that colors have faded but areas covered with laminate (you may need a laminate with special adhesive to adhere to the UV ink) or with varnish still look good after three years.

Instead, the real problem with UV inks (Mutoh, or in general?) is that there seems to be some kind of over curing when exposed to sunshine (UV light and/or heat?).
Some of my tests objects were vinyl stickers, and it didn't take more than a couple of months before stickers covered with ink started to curl and eventually more or less fell of the test panels (painted aluminium sheets).
The UH21 ink also became very "crisp" and the vinyl would break when folded. This friability is something I have seen also with stickers stored indoors over time.
I know the UH21 ink isn't really suitable for soft or stretchable materials but this was much worse than I would have expected.

Some of my tests were also printed directly on prepainted aluminium, and I could see small cracks all over the surface over time in areas covered with ink.
My guess is that this is due to expansion of the aluminium sheet when exposed to heat, where the ink isn't flexible enough to stretch along with it.

About six months ago, I switched to the more flexible US11 ink set, to see if I could broaden the area of use for the printer.
The ink is indeed more flexible but not as scratch resistant as the rigid UH21, and it is less durable against solvents.
I have seen curling starting to appear after some months, especially on stickers with yellow ink along the edges.
A layer of varnish seems to hold back the effect a little, but I'm not yet sure how much.

So, in short, my experience tells me that the colors are as good as solvent inks when it comes to fading, maybe even a little bit better because of the thicker ink layer.
Varnish, which is quite easy to add when using an UV printer, will extend the outdoor durability.
The rigid ink becomes too hard to use on soft or stretchable materials and the flexible ink may be a better choice in some situations, but unfortunately it isn't possible to switch back and forth between rigid and flexible ink sets.