Moldy vinyl?

[DesireeM]

So this issue is very rare to me but this is the 2nd time I've seen it in the 8 years I've been working in this industry so I wanted to see if anyone knows what is going on and if it's something we've done or that can be avoided...

There is a discoloration/mold that seems to affect only the vinyl on a couple signs we produced years ago. I'm not sure if it started right away or how long it took for the mold to get to the point it's at once the customer contacts us but both of these jobs have the same thing going on - it may not even be mold but that's all I can guess.

In the attached photos the 2 signs from the same 4-year-old job have the black discoloration. They were eco-solvent printed on cast vinyl, laminated and applied to ACP using a flat bed application table. The one with a frame is also ACP - the customer did not want to repair/refurbish the sign box.

The third photo is a close up of the most recent job that has this same mold/discoloration. It was done over 10 years ago so I'm not sure what grade of vinyl was used but it is printed on transparent vinyl, lamianted and applied to a white acrylic sign face for a backlit box. As you can see there is no mold where the frame was covering the vinyl and the mold did not affect the acrylic.

Any thoughts, comments, advice?

 

[Solventinkjet]

Looks like a 10 year old sign to me. I don't know of any vinyl combination that claims to be able to last over 10 years. Time for a new sign! I have a large sign outside of my building that was printed and laminated about 8 years ago. It looks very similar what yours does. With ours it's more sun damage than anything. I'm not sure if what you are seeing is actually mold but if it is, it's probably from water seeping in between the vinyl and laminate through the years. Either way, 10 years for a printed sign is past it's due date.

 

[DesireeM]

Looks like a 10 year old sign to me. I don't know of any vinyl combination that claims to be able to last over 10 years. Time for a new sign! I have a large sign outside of my building that was printed and laminated about 8 years ago. It looks very similar what yours does. With ours it's more sun damage than anything. I'm not sure if what you are seeing is actually mold but if it is, it's probably from water seeping in between the vinyl and laminate through the years. Either way, 10 years for a printed sign is past it's due date.

Yes, they have all been replaced. The sign from the third picture is the only one that was around 10 years old. The other two photos are signs that were no more than 4 years old though so I can't deduce that it's simply an "old sign" problem. We replace old sign faces and vinyl constantly with varying ages but only in these two cases in the last 8 years have I seen this discoloration. I just feel like there's more to it than age but maybe it's just a random environmental thing where these mold spores are in the air and just happen to find these signs in particular.

 

[letterman7]

That's not mold - that's material failure. More specifically, the adhesive layer. JBurton is right - for an ecosolvent, outgassing is extremely important before running it through a laminator. That said, that sign must have had (still have) some significant sun exposure to cook it that bad. I didn't think your climate got that much exposure

 

[2B]

we have seen similar with certain laminations
specifically the Oracal 210G.

The other point is if vinyl is compatible with the lamination
We tested some private labels with the 210G Cal laminations and depending on the combination they would show the discolorization sooner than if the vinyl & lamination was from the same company

 

[chester215]

My first thought is if it is mold are there lawn sprinklers around, soaking it daily?

 

[DesireeM]

That's not mold - that's material failure. More specifically, the adhesive layer. JBurton is right - for an ecosolvent, outgassing is extremely important before running it through a laminator. That said, that sign must have had (still have) some significant sun exposure to cook it that bad. I didn't think your climate got that much exposure

So when you say it's an adhesive failure do you mean the adhesive is seeping through to the front of the vinyl and turned it black? Because none of the vinyl was separating or peeling from the ACP surface. It was still very firmly stuck to the substrate. And the discoloration is only on the front of the vinyl - the adhesive was not discolored. (It's hard to tell on the last photo because it is transparent vinyl but the black is only on the front. The other two signs were printed on opaque vinyl and the adhesive side was unaffected.)

I'm not saying it's not an outgassing issue but wouldn't there be a trend in that regard if that was a cause? I can't guarantee that all of our prints over the years have had sufficient enough time to outgas BUT I can say this - we create thousands of vinyl graphics per year and don't put a big priority on outgassing - some graphics sit for a couple days, some for a few hours, some more or less than that and I have not seen vinyl failures to a concerning extent - including outdoor, vehicle wraps, reflectives...whatever it is. I can count on one hand how many of our graphics have had mysterious failures so from our point of view there's no correlation.

On top of that - the two signs I have photos of were part of a group of signs we made for that property. There were 4 more signs produced on the same material and printed at the same time, installed at the same time which are in great shape even now. No discoloration.

 

[DesireeM]

My first thought is if it is mold are there lawn sprinklers around, soaking it daily?

Would be a good guess but there are no sprinklers on the property. And the third image is from a backlit sign that is above a strip mall entrance.

 

[DesireeM]

we have seen similar with certain laminations
specifically the Oracal 210G.

The other point is if vinyl is compatible with the lamination
We tested some private labels with the 210G Cal laminations and depending on the combination they would show the discolorization sooner than if the vinyl & lamination was from the same company

This could be something....but there are 4 other signs we made for the same job. Same vinyl, laminate, printing, install on the same property, same day and they are all fine.

 

[letterman7]

So when you say it's an adhesive failure do you mean the adhesive is seeping through to the front of the vinyl and turned it black? Because none of the vinyl was separating or peeling from the ACP surface. It was still very firmly stuck to the substrate. And the discoloration is only on the front of the vinyl - the adhesive was not discolored. (It's hard to tell on the last photo because it is transparent vinyl but the black is only on the front. The other two signs were printed on opaque vinyl and the adhesive side was unaffected.)

I'm not saying it's not an outgassing issue but wouldn't there be a trend in that regard if that was a cause? I can't guarantee that all of our prints over the years have had sufficient enough time to outgas BUT I can say this - we create thousands of vinyl graphics per year and don't put a big priority on outgassing - some graphics sit for a couple days, some for a few hours, some more or less than that and I have not seen vinyl failures to a concerning extent - including outdoor, vehicle wraps, reflectives...whatever it is. I can count on one hand how many of our graphics have had mysterious failures so from our point of view there's no correlation.

On top of that - the two signs I have photos of were part of a group of signs we made for that property. There were 4 more signs produced on the same material and printed at the same time, installed at the same time which are in great shape even now. No discoloration.

No, not seeping, but actually failing. Top layer first, and generally you won't see it once peeled oddly enough. Years ago when Avery was having it's issues I had dozens of police cars with reflective showing these exact properties, and it was the top layer of the vinyl (the "color" part) failing from the bottom layer. But when I peeled it off it still came off in one piece.

Odd that other signs you've produced at the same time haven't had the same issues. Are they all pointing in the same direction (i.e. same amount of daylight and weather exposure)? Is it possible (if you have employees) that someone grabbed the wrong laminate for those few that are failing?

 

[DesireeM]

No, not seeping, but actually failing. Top layer first, and generally you won't see it once peeled oddly enough. Years ago when Avery was having it's issues I had dozens of police cars with reflective showing these exact properties, and it was the top layer of the vinyl (the "color" part) failing from the bottom layer. But when I peeled it off it still came off in one piece.

Odd that other signs you've produced at the same time haven't had the same issues. Are they all pointing in the same direction (i.e. same amount of daylight and weather exposure)? Is it possible (if you have employees) that someone grabbed the wrong laminate for those few that are failing?

I see what you're saying. I'm not sure if those two in particular have more direct sun exposure. As far as the laminate - it could be a factor but again I have no way to know for sure if that happened. I would think if that was the case I would have seen this issue more often as I'm sure it's happened more than twice over the years where lams were mixed with other vinyls accidentally. It's really just boggling me because it could be a number of things but it's so rare that it seems like it should be a rare action that preceded the vinyl failure. But moisture, weather exposure, incorrect vinyl/lam combination, not enough outgassing are all factors that I would think happen more than twice in 8 years.

Perhaps it's just a "perfect storm" type of thing...where the shop error plus the weather/moisture etc combines to create this type of failure.

 

[equippaint]

Is it possible that it has very little sun exposure rather than too much? Mold can stain surfaces and if there's no sun to dry off the morning dew you will have a problem.
Is that sign using a dead tree as a post?

 

[Snydo]

My guess is the area that was flooded with blue ink was not sufficiently cured before lamination. That is a prime example of laminate that has reached the end of its life cycle. What all the big vinyl manufacturers fail to tell you is that 4 or 5 years of minimum life expectancy is based on being mounted to unprinted stock in a vertical position, once you add ink, especially ink that has not completely dryed all bets are off as you are essentially changing the chemistry of their product.

 

[DerbyCitySignGuy]

That looks like UV damage, probably not mold.

Check out this picture and see the similarities. Had this same issue come a couple years ago (had never seen it before). You can see the screw hole covers, which were just laminated white vinyl, are undamaged, where as the printed and laminated vinyl is toast.

It's probably some combination of everything that was mentioned in this thread (end of life of the vinyl, too much sun, not properly outgassed) that caused your issue.

I've seen this A LOT more often since the time this picture was taken. Can only imagine why.

 

[DerbyCitySignGuy]

I started seeing it around the time a couple of print shops popped up around me claiming to be sign companies...

I think that's a big part of it. There are a lot of people on the forums who are "outgassing-deniers" and it's a big conspiracy for some reason. I have no earthly idea what that reason might be, there doesn't really seem to be any gain for 3M or Avery (or whoever) to ask you to wait for outgassing, but people still think it's a conspiracy.

I will say that material failures seem to be a lot more common than they used to be. Even just five years ago, we didn't seem to have the same amount of issues that we're currently seeing, especially with some of the "budget" materials. Still doesn't excuse laziness or ignorance, but I can give people the benefit of the doubt.

 

[Jester1167]

My guess is the UV rays from the sun. Do the failed signs consistently face the south? (They look like 2 sided signs) I have seen this on lots of signs in Florida and my initial thoughts were cheap material.

 

[KMC]

I have seen this happen to signs up here in sunny southern alberta, but mainly on the ones which face south and get the most sun
we find that it usually starts to happen around the 4 year mark and then gets worse quite fast
its a UV issue burning the ink under the laminate and then spreading making it black it, it happens with both solvent and latex ink
we advise our clients the typical life span of the matching vinyl and laminate and advise that its an "up to X amount of years" it is not going to last as long at any angle facing up and facing south etc

 

[unclebun]

I have seen this happen to signs up here in sunny southern alberta, but mainly on the ones which face south and get the most sun
we find that it usually starts to happen around the 4 year mark and then gets worse quite fast
its a UV issue burning the ink under the laminate and then spreading making it black it, it happens with both solvent and latex ink
we advise our clients the typical life span of the matching vinyl and laminate and advise that its an "up to X amount of years" it is not going to last as long at any angle facing up and facing south etc

This is the answer. It's just the sun burning up the sign. An important point to remember in deciding whether to print or to use cut vinyl to make a sign. Even calendared cut vinyl ages more gracefully than sunburned digital prints. They either turn black like this or disappear to white (especially when unlaminated).

 

[equippaint]

I think that's a big part of it. There are a lot of people on the forums who are "outgassing-deniers" and it's a big conspiracy for some reason. I have no earthly idea what that reason might be, there doesn't really seem to be any gain for 3M or Avery (or whoever) to ask you to wait for outgassing, but people still think it's a conspiracy.

I will say that material failures seem to be a lot more common than they used to be. Even just five years ago, we didn't seem to have the same amount of issues that we're currently seeing, especially with some of the "budget" materials. Still doesn't excuse laziness or ignorance, but I can give people the benefit of the doubt.

I'm not being an "outgassing denier" here but don't you think you would have seen more of this in years past when most everyone was running solvent printers? If outgassing were the culprit, you would think that we should be seeing less and less now as eco-solvent ink formulations have changed to a faster dry time and latex and UV is more prevalent.

 

[DerbyCitySignGuy]

I'm not being an "outgassing denier" here but don't you think you would have seen more of this in years past when most everyone was running solvent printers? If outgassing were the culprit, you would think that we should be seeing less and less now as eco-solvent ink formulations have changed to a faster dry time and latex and UV is more prevalent.

No, we've always outgassed and continue to outgas. Very, very rarely do we skip outgassing. It's been cropping up a lot more frequently, which I suspect might have something to do with the composition of the materials more than anything else. I'm not sure what goes on in other shops, but I know that in our shop, that sign was the first time I'd ever seen that issue.

I also wasn't trying to imply that outgassing is the sole reason for this. It's one of the many corners people can cut.

Like I said initially, this looks more like straight up UV damage. Could be other contributing factors. I'm not a chemical engineer.