Huge problem after finishing (excessive heat)

they only noticed it after it was packed in boxes to be shipped... it felt like the heat was being generated inside the boxes, and it was increasing.

Didnt the guys in finishing notice any heat and you would have thought that going through a couple of other processes someone would have said something.
 
If the paper is on the alkaline side say 8.00 ph or higher in combination with the acidic fountain solution and with the bio based inks that have a high concentration of mag and cobalt dryers and the sealing varnish you have the perfect storm for heat generation. When anything oxygenates it gives off heat.
In the closed container there is no were for the heat to dissipate and it just increases in temperature. It could quite possible get to the point of self combustion. If there were any caustics in the paper this could also aid in the temperature increase. Caustics and acids combined love to make heat.

This same problem can occur when wet or damp hay, straw or silage is placed in a mow or silo they can self combust.
 
I agree that it sounds like an adverse chemical reaction. However, it might not be the supplies, but, the step-by-step process you used in this specific instance.

You say you are using the same paper, ink, & varnish that you always use, and, this has never happened before.

Think carefully, did the work-flow on this job vary from your normal workflow? What's different about this specific run from your previous runs. Was it a rush? Is it possible the ink wasn't completely dry before you applied the varnish? Were the books compressed tighter into the boxes than normal?
 
It is called an exothermic reaction and I have seen exactly the same thing, no heat at all in the drying process, came in the next morning to find the stack red hot and the ink, which was an overall solid of light blue changed colour to light green, if I had not seen it with my own eyes I wouldn't have believed it, ink reps told us it is the heat given off during the drying process.
 
If the paper is on the alkaline side say 8.00 ph or higher in combination with the acidic fountain solution and with the bio based inks that have a high concentration of mag and cobalt dryers and the sealing varnish you have the perfect storm for heat generation. When anything oxygenates it gives off heat.
In the closed container there is no were for the heat to dissipate and it just increases in temperature. It could quite possible get to the point of self combustion. If there were any caustics in the paper this could also aid in the temperature increase. Caustics and acids combined love to make heat.

This same problem can occur when wet or damp hay, straw or silage is placed in a mow or silo they can self combust.

From memory the Novavit 918 bio doesn't use cobalt as a drier due to the fact its listed as a carcinogen, don't have the msds in front of me so not sure what the substitute is.

What are the reasons alkaline paper would cause such a reaction ? I would assume most paper these days are around that PH or maybe higher.
Frightening thought of what could have happened.
 
Rushed!

Rushed!

Hello fellow Lithographers,

My Opinion,

1) A rushed through put from press to bindery, insufficient time given for

normal oxidation drying of ink, overprint varnish and paper combination.

2) I also think that the WFU (Woodfree Uncoated) text paper played a

signficant role.


Salient Point - All modern commercial uncoated printing papers are

made to be neutral(pH7) or slightly alkaline.



Regards, Alois
 
From wikipedia

Linseed oil

Spontaneous combustion[edit]

Rags soaked with linseed oil stored in a pile are considered a fire hazard because they provide a large surface area for oxidation of the oil, and the oil oxidizes quickly. The oxidation of linseed oil is an exothermic reaction, which accelerates as the temperature of the rags increases. When heat accumulation exceeds the rate of heat dissipation into the environment, the temperature increases and may eventually become hot enough to make the rags spontaneously combust.[32]
In 1991, One Meridian Plaza, a high rise in Philadelphia was severely damaged and three firefighters perished in a fire caused by linseed oil-soaked rags.[33] In 2011, a garage in Sacramento also caught fire due to the spontaneous combustion of linseed oil-soaked rags.[34]


Replace the rags with paper and put them in a box

this link offers much more in-depth info Fire Science Reviews | Full text | Low temperature oxidation of linseed oil: a review

another good link Re: linseed oil (was exothermic/endothermic)

Tung & Linseed Oils

drying oils http://en.wikipedia.org/wiki/Drying_oil
 
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I think you should make contact with Flint Inks and find out how much "drier" they mixed into the batch of ink you are using.
Oxidative drying does cause heat to be generated but as hot as you describe, definitely not.
Does 'airing' the product out help you.
Getting the heat away from it should help.
If there is too much drier the problem
will not go away until the chemical reaction stops.
451 deg F is the ignition point of paper. I don't think you can make it to that temperature but you never know. Good job thinking about the air line guys, I cannot think of a worse scenario than a fire on board especially in a place that's inaccessible like a cargo hold.
 
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Ahhhhh, the many joys of STAY OPEN inks. Try an ink series that actually relies on the oxidative process rather than setting and protective coats. D
 
I saw something similar once, the job was printed, AQ coated, folded and boxed, Upon delivery to the customer the boxes and contents were hot, and the entire job was now bricked (coating).

Samples were sent to some experts, it was discovered that an exothermic chemical reaction caused the problem.
 
Are you sure it was AQ coated and not Varnished? I am questioning because in one of the emails of flint's support they mentioned that AQ coating help resolve the problem.

I saw something similar once, the job was printed, AQ coated, folded and boxed, Upon delivery to the customer the boxes and contents were hot, and the entire job was now bricked (coating).

Samples were sent to some experts, it was discovered that an exothermic chemical reaction caused the problem.
 

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