Curing or "degassing" before lamination

[joeshaul]

How many of you know how to put gas in your car, maybe even oil, steer it and park it, yet don't have the smallest inkling how the engine runs and the mechanics behind it ?? You drive around and do all kinds of things with your car, but you have no qualms with what makes it run. So...... why do you have to know how this vinyl solvent stuff works if you don't want to follow the rules ??

I've outgas'ed my car before, and it is no myth!

 

[bob]

When I sheet lam a sign face sometimes I'll cut the laminate and then let the vinyl and the laminate sit on the table overnight to get any curl out of it if it's from the end of a roll.

In the morning I can see a ghost image of the print in the laminate release liner from where the print was outgassing. I also see the same thing in longer banner runs when you unroll the banners from the take up reel. You can see how the banner material has stretched from the ink.

The ink solvents DO soften the vinyl and weaken the adhesive bond. This is not a myth.

If the ink turned the vinyl into so much pulsating tapioca and the odor caused anyone near to it to run out into traffic it would not constitute evidence for the existence of 'outgassing' as being posed here in this sandbox.

Or is it the case that any physical phenomenon generated by solvent in on vinyl is what you mean by 'outgassing'? If that's the case then the term has no real meaning.

 

[Jester1167]

Bryce Schaefer, a regional business manager for 3M Graphics Market Center, made a presentation at 2007’s SGIA conference entitled “Understanding the Effects of Ink on Digital Printing.” His presentation materials state, “Virtually all solvent-based inkjet inks contain a very high percentage of solvent (roughly 90%), even so-called ‘eco’- solvent inks. High solvent levels cause the film to swell and/or become soft and gummy, [and the solvents] can migrate to the vinyl’s adhesive and cause graphic failures.” Excessive ink saturation within the media may prove to be the culprit. When using self-adhesive, vinyl films, Schaefer recommends not exceeding a 270% ink-saturation level. Even 300% saturation is excessive.

He described a solvent-migration test that 3M conducted by printing black rectangles on white vinyl. The unprinted white was laminated and used as the control sample. Technicians unrolled the prints and laid them flat on a table to allow solvents to escape. When graphics are tightly rolled (as they arrive off most printers), solvents can only escape from the outer layer. 3M’s technicians laminated the first black rectangle immediately after printing. They followed successive rectangles with incrementally more curing time. After lamination, they installed all pieces, including the control sample. The graphics were allowed to wet out for 72 hours to reach an ultimate bond. As the graphics were removed, 3M measured the pull force (which measures the level of adhesion) required to remove them. The test showed, the longer the prints were allowed to cure, the greater the pull force. It took 20 days of curing for the final sample to achieve the same pull force as the unprinted control sample.

This proves that solvents adversely affect vinyl adhesion. Ironically,poorly cured graphics adhere much more aggressively during installation than the same, unprinted vinyl. How does this happen? The answer is really pretty simple. Most fabricators print on digital media with repositionable adhesives. Typically, you initially place the vinyl by not touching the entire adhesive to the surface. Imagine viewing the adhesive under a microscope.You would see a textured surface. Only the adhesive’s higher points touch the surface initially, which makes initial tack less strong. When you squeegee with pressure, the adhesive flattens and makes full contact. When a repositionable-adhesive vinyl absorbs excess solvents, it becomes very soft. This defeats the film’s workability and allows the adhesive to make full contact. Consequently, although the adhesive has weakened, it acts more aggressively because more of it touches the surface.

I attended that class an there was alot of good information about solvent retention. Below are other manufactures recommendations and data.

http://www.oracal.com/products/_docs/prod-bulletins/3951RA_041807.pdf 24 hours
http://mactac.com/fileadmin/user_upload/Graphic/Technical_Assistance/TA2100DigitalPrinting101.pdf 24 hours
http://www.arlon.com/DownLoadFile.aspx see attached pdf file.

 

[GAC05]

Bryce Schaefer, a regional business manager for 3M Graphics Market Center, made a presentation at 2007’s SGIA conference entitled “Understanding the Effects of Ink on Digital Printing.” His presentation materials state, “Virtually all solvent-based inkjet inks contain a very high percentage of solvent (roughly 90%), even so-called ‘eco’- solvent inks.>>>>>> Blah blah blah....

There you go .... trying to cloud the issue with things like facts, controlled studies from the companies that make these materials.
What forum do you think you are posting on?



wayne k
guam usa

 

[luggnut]

"facts are overrated ... you can use facts to prove anything that's even remotely true"

quote from homer j. simpson

 

[Techman]

Hell yes, at those high levels what the hell would any one think is goona happen. The ink as almost dripping off the vinyl.

I'm not sure about those sat levels because I'm not sure if there is an apples to apples comparison.

However, I have almost never printed at more than 100%. In fact I cannot remember ever printing at more than 100% simply because the ink runs all over the place.

 

[Jester1167]

I don't think I have seen a profile below 180%. On a 4 color machine you have the potential to print 400% (100% of each color). A 6 color machine 600%. Typical profiles are between 180% - 280%. Alot of people use C60 M60 Y60 K100 for good dark black and that's 280%.

 

[ProWraps]

Hell yes, at those high levels what the hell would any one think is goona happen. The ink as almost dripping off the vinyl.

I'm not sure about those sat levels because I'm not sure if there is an apples to apples comparison.

However, I have almost never printed at more than 100%. In fact I cannot remember ever printing at more than 100% simply because the ink runs all over the place.

heh.