Weird bricking problem on Stone Paper

[Wheels]

We ran a job on Stone Paper (made from Calcium Carbonate rather than pulp). The normal description of this is that the job bricked but with a twist. Sheet 1 is stuck to sheet 2. Sheet 2 is Not stuck to sheet 3. Sheet 3 is stuck to sheet 4. Sheet 4 is Not stuck to sheet 5. And so on. Job was run sheetfed on 29" press. The job is a map and it is impossible to fan the paper to break it apart and get it to feed through the folder. I am totally stumped as to how/why this happened. Has anyone seen anything like this on traditional paper or other? Thanks

 

[turbotom1052]

Sounds to me like the paper was sheeted off of multiple rolls with one of the rolls being defective. This would account for the some good and some bad you describe.

 

[Wheels]

Thanks Turbotom. That is the only logical conclusion I can come up with. I can't wrap my head around any other cause.

 

[turbotom1052]

the pattern that it follows would be a good indicator of just how many rolls.

 

[D Ink Man]

Good job turbotom1052 sir on the probable cause.

Now perhaps we can take it to another level for treatment. Let's just say that this stock, maybe CCN, is a stock that you are married to. You have to use it, no other choice.

Now Wheels if you submit just a bit more information, a thorough diagnosis and remedy can be given.

Without going into all other consumables, let's concentrate on 3 things. 1) Ink coverage 2) Ink type; spot or process and what exact brand of ink you are using. Do not leave any details out. If you can, take a photo of the label('s) on the containers and post them. 3) Fountain Solution recipe.

We all know the probable WHY now, let's see if we can find a remedial solution. That is the part of the fun.

D Ink Man

 

[Alois Senefelder]

Gentlemen,

Just to "muddy the waters" ! The multiple reels (rolls) that are used for the Sheeting Machine. ALL originate from ONE - 4/7 meter wide reel (roll) ,

these are then sequential used for sheeting, this eliminates variation.

Regards, Alois

 

[Wheels]

Alois Senefelder - Even though the multiple rolls come from one original roll, the every-other-sheet different results sure make it seem like there is a difference between the rolls used at the sheeter. I don't know enough about the intricacies of the paper making process, but would you rule out some sort of defect or inconsistency that shows up because of the sheeting mix? I'd love to learn more.

As a side note, I ran a job on the same stock a week prior. The job ran well and folded well and we did not have this "bricking" issue. However there was a dramatic difference in the opacity of every other sheet on that run. You could see through the paper, every other sheet. So, this is the second job where I am getting completely different results on the odd numbered sheets than the even numbered sheets. Fortunately on the first job, it was only cosmetic. On this second job, the sheets sticking together has made it impossible to get it through the bindery.

 

[Alois Senefelder]

Hello Wheels,

We need to know more facts about this Paper - 1) Matt or Gloss coated ? 2) The GSM ? 3) This is crucial ! -- Who manufactured the paper and where it was made ???

Also, answer the questions that D Ink Man raised about INK.


Regards, Alois

 

[Wheels]

D Ink Man - I will assemble the chemistry details on Monday for you. Alois Senefelder - I will compile paper specs on Monday for you. Both will be posted for your observations. Thanks

 

[turbotom1052]

something I'm curious about.... Did you run this job on a press with closed loop color control? I recall you talking about the variations in papers opacity. If there was a lot of variation in papers opacity from sheet to sheet, that could have made for color control through closed loop inking to be a big challenge. The scanning densitometer reads a sheet with very low opacity. The software tells the inker give me more ink. The next sheet pulled for a scan has a high level of opacity. The software tells the press less ink. You get where I'm going with this???

 

[Wheels]

@turbotom - Job ran on a 3 year old Komori 29" press with Spectrophotometer and ink adjustment. The opacity issue was on a job we ran a week earlier, so opacity wasn't a noticeable factor in this job. I understand where you are going with the question.

However adjustment of the ink density should not impact the first sheet, not the 2nd, but then impact the 3rd sheet. In the first job, it was easy to visually see that every other sheet was different (but it didn't impact production). In this case, I can't visually see a difference between sheets, but after running the job, every other sheet is sticking to the sheet before it.

If it was a humidity issue, a static issue, a stacking/weight issue, an ink issue, or a chemistry issue, my contention is that it would impact every sheet, not every other sheet.

 

[turbotom1052]

sorry I confused the opacity issue with the blocking issue. I still stand by my original suggestion of a bad roll when sheeting. Do you know if the paper was a direct mill purchase, or was it purchased through a paper merchant who upon delivery to them in roll form converted it to sheets for sale to you?

 

[Alois Senefelder]

Gentlemen,

Credit to "turbotom" for the possibility of a "Rogue" Paper Merchant and the Sheeting, I forgot, after so many years in which the companies I worked for WE only ever bought

direct from the Paper Mill under contract, Millions of Meters !!!!

Regards, Alois

 

[Wheels]

D Ink Man Alois Senefelder
The stock is: Stone Paper Solutions RP120 Micron Text. (approx .0047" thick) The paper is made from calcium carbonate, recycled concrete and a small amount of high density polyethelyene. I believe the mill is offshore, sheeted and then shipped to North America.

Ink is: Hostmann/Huber CMYK. Image attached.
Fountain Solution is a two part solution: Flint Group Supreme 8168 (2part/gal) and Fuji ARS ML (1 part/gal)

Job is CMYK. Medium coverage with a couple of 2" blue bars. The sticking is happening mostly where this heavy coverage is. Normal powder was used on the job. In hindsight, I would have used much more powder.

 

[Alois Senefelder]

Hello Wheels,


Do try and be "Sensible" with your description of the "Substrate" !!!! ..... no such paper exists that you describe, NOW show us a Label from a ream or pallet of paper.

Regards, Alois


PS, was any UCR/GCR done by the Pre Press regarding the Halftone Colour Separations ???????

 

[D Ink Man]

I am assuming no aqueous or other overcoat was applied on job.

If you can take each sheet subject and place a drop (preferably a microliter drop) of fount on no coverage area (blank), see if you see any difference in the time the drop takes to completely dive into the substrate. If you see a significant difference after a couple of tests, you may have fodder to go after your paper supplier. Don't know.

Also, that H/S ink is a common ink used in the field. Only thing further would be to know the VOC level on it.

Spray powder is a very good point. Monday morning quarterbacking I would say not to increase the amount of your application; rather increase the micron size of your powder from say a 35 to maybe 45 or 55 and cut back slightly on the feed.

Other than that, this advice is the best I can think of, up to now.

D

 

[AP90]

Hello Wheels,


Do try and be "Sensible" with your description of the "Substrate" !!!! ..... no such paper exists that you describe, NOW show us a Label from a ream or pallet of paper.

Regards, Alois


PS, was any UCR/GCR done by the Pre Press regarding the Halftone Colour Separations ???????

Actually this paper very much exist. Ill even post the link to the website, which I found in 2 seconds by copying and pasting what he said the stock was into Google.

http://www.stonepaper.co.nz/about-rockstock

 

[Alois Senefelder]

Hello AP90,


Well what can say - BUT how wrong can I be - sorry, never ever heard about this so called PAPER,

now I'm going to hang my head in shame !!!!!


Regards, Alois


PS - I think they have a nerve even to call it PAPER - WHEN it is a Laminate Product !!!!!


PPS - I await the "Hue and Cry"

 

[Wheels]

Alois Senefelder - Here is the skid label.

 

[turbotom1052]

Considering all the problems associated with calcium buildup in presses rollers, its beyond me why anyone would want to tempt fate, by printing a substrate which is composed mainly, of the very substance that gives us so much trouble. Perhaps there may be some day when this new fangled printing substrate will have its place in modern offset printing, but I doubt that this is the day. Id say the rest of the various consumables industries need to release products that will work with this new stuff before we even attempt to use this with any regularity. I suspect that the release of consumables to include inks, fountain solutions, roller washes etc. are a ways off, if even on the consumable manufacturers radar.