The truth about outgassing

[PrintItBig]

We have a whole load of 50M rolls of eco solvent prints that need to be outgassed before lamination.

I've read the thread a bit further down the board about unfurling the roles and raising them up so the solvent can effectively fall out of the bottom.

Is this really a necessary step to outgass or is this just to speed up the process?

If we were to simply stand the rolls up on their ends, not raised up, still rolled tightly and leave for 24 hours would this be adequate?

Unfurling a 50M roll is an absolute PITA and then it has to be "refurled" again so it can be laminated. We've got lots of these to do and if we could just leave them rolled standing on their ends it would make life a lot easier.

Would prefer to increase the 24 hour time rather than unfurl.

Please comment.

Thanks.

 

[Bly]

Unless it's for wraps I wouldn't worry about it.

 

[Techman]

The truth is... In y opinion...

I would do a study of the volatility of alcohol based products. That is find our for a fact how fast does the alcohol evaporate.

Alcohol evaporates much faster than ether. How fast does ether evaporate?

Ether Evaporation Rate (BuAc=1):37.5 ... what does that mean? Well it means it evaporates fast. For example. Water is down around .3 So we can see it dries very fast when compared to water.

How fast is alcohol? Some is 8 times faster than ether. Some is over 100 times faster. Since ink is a combination of alcohols as a solvent it would seem the dry rates is averaged out. However, this is not true. It will evaporate out at its own rate according to each variation.

As for outgassing? This is some misused word made up by some technician to explain dry times. Outgassing of prints? 98% of the time it is a myth. Alcohol evaporates out in mere seconds because the amounts laid down are very minute. It takes more than that for the print to enter the take up roll. 2% of the time the solvent is on so heavy it permeates the substrate and actually starts to disolve the plastic. That is not so good. If the ink is that heavy then some setting is wrong.

 

[Jack Knight1979]

For what it's worth.

I print rolls of wrap vinyl a week. While I do wait a day to laminate them, I do not unfurl the roll for "drying". Have I had a problem yet? No.

 

[cmykpro]

I wait 2 hours on every type of eco-solvent print I run and have never had an issue with lam. Going on 12 years now dating back to the early Mutoh days....

 

[PrintItBig]

Unless it's for wraps I wouldn't worry about it.

Thanks.

 

[PrintItBig]

The truth is... In y opinion...

I would do a study of the volatility of alcohol based products. That is find our for a fact how fast does the alcohol evaporate.

Alcohol evaporates much faster than ether. How fast does ether evaporate?

Ether Evaporation Rate (BuAc=1):37.5 ... what does that mean? Well it means it evaporates fast. For example. Water is down around .3 So we can see it dries very fast when compared to water.

How fast is alcohol? Some is 8 times faster than ether. Some is over 100 times faster. Since ink is a combination of alcohols as a solvent it would seem the dry rates is averaged out. However, this is not true. It will evaporate out at its own rate according to each variation.

As for outgassing? This is some misused word made up by some technician to explain dry times. Outgassing of prints? 98% of the time it is a myth. Alcohol evaporates out in mere seconds because the amounts laid down are very minute. It takes more than that for the print to enter the take up roll. 2% of the time the solvent is on so heavy it permeates the substrate and actually starts to disolve the plastic. That is not so good. If the ink is that heavy then some setting is wrong.

So is that a yes to unfurling them or no, not nessesary?

Thanks.

 

[PrintItBig]

For what it's worth.

I print rolls of wrap vinyl a week. While I do wait a day to laminate them, I do not unfurl the roll for "drying". Have I had a problem yet? No.

Thanks. So would you say they could be just left rolled up on printer / take up reel for a day?

 

[PrintItBig]

I wait 2 hours on every type of eco-solvent print I run and have never had an issue with lam. Going on 12 years now dating back to the early Mutoh days....

Do you unfurl them, use a fan or anything like that? Or just leave them on the printer rolled up, wait 2 hours then lam? Thanks.

 

[SightLine]

We have printed literally thousands of rolls. We have always just took the roll off the printer and stand it on end until its time to laminate it. Usually 12 to 24 hours or so. Even when printing full bus wraps which truly use an entire 54" x 50yd roll. Just stand them on end still tightly rolled just as they came off the printer. No problems in 10 years from it.... and we run full solvent inks in our Mimaki (and always have). We actually just removed a wrap from a full size Ford van last week that we printed and installed in July of 2007 (printed on 3M 180C with 3M lam). While far from perfect after nearly 7 years, other than the perf the wrap itself still looked very good and presentable. There was some minor cracking along the top edges but it still removed very cleanly without breaking up and very very little adhesive left behind. This van was never once waxed or kept indoors either.... The paint underneath looked essentially new while the van itself was a ragged out worn out piece of crap by now. The wheels and bumpers looked bad and the interior looks bad but hey - nice paint! lol