Reducing drying times on uncoated stocks

[Colin Gilham]

Hi all,

Increasingly it seems we're being required to produce everything with lower than ever turnaround times - I'm sure everyone knows the feeling - and, more and more, that includes uncoated stocks.

The question is how to reduce drying times with our regular setup?

We've been using hard-drying inks which are great but they're expensive and mean an ink change every time they're used so long term, it's not a viable solution.

We use Druckfarben's Eco Perfecta Intense range with Bottcher S3006 fount & 5% alcohol on Komoris - a 528 and 1028P, both with IR dryers that are currently out of commission due to what we consider to be uneconomical repair.

So far I've had thrown up - adding driers, adding a small amount of varnish to the ink, using IR drying, coarser screen ruling (not sure about that one at all - won't affect solids). None of these suggestions are met with universal agreement, opinion is based on experience so you get a different idea whoever you speak to.

Generally speaking we're not unhappy with the drying times, they're good across the board, if there's anything we can do for uncoated stocks it would be great.

Anyone have any ideas?

 

[Asures]

Many people have a strong confusion between "Rub / Scuff Resistance" and "Drying."

If you are looking for better dry times on uncoated stock, certainly a Hard Dry version of ink isn't going to help. Hard Dry inks, similar to high solid inks, will give you a better cure and bonding once the ink is dry thoughout all levels of ink on the sheet. Hard Dry Inks actually dry slower than standard inks.

Adding dryers to the ink will speed up the oxidation process but won't help with rub or scuff if that is your problem. I'm saying that because someone is bound to suggest a drying additive to add.

You might want to talk to your ink supplier and see if they can give you a "High Rub Resistant" or a "High Slip" ink for those specific applications. In summary, they will add additional waxes to the ink that will allow the sheets to be handled without the fear of scuffing in a shorter time ratio. The inks set as well or as fast as a standard ink, just have better rub. This ink should not be used if you are going to foil stamp, laminate, or UV coat the job, after being printed. Those particular waxes are generally not going to be finish friendly.

Again, it's a special ink that you might not want to inventory or spend the money on. With ink being 3% maximum of the entire job, what's another 25% higher price on the ink if it works and saves face in front of your client..

Good Luck!

 

[Greg_Firestone]

Just curious if you're running any type of ink saving software. The reason I ask is less ink on a page should result in faster drying times.

- Greg

 

[Brer]

We were having the same trouble along with some drying and picking issues on our gloss stock. We were using Gans Bengal line. After talking with our sales guy we switched to their Eco-sure line. We can turn jobs faster and have less scuffing on our uncoated stock. I would talk with your ink salesman.

 

[Frank Giese]

You mentioned that you are "required to produce everything with lower than ever turnaround times" and that you want to reduce ink drying time.

On average what is your required turnaround times. I am trying to establish how significant the ink drying time is in the total time (From order receival to delivery)

 

[TonyD]

Take a look at the newest Cougar swatch book from Domtar (we printed it over a year ago so you may have the latest copy). If you look on the back cover of your book and see that it was NOT printed on a Komori, then you've got the old version. Anyway, the ink we used to print the book is called Truetone Hi-Def and it is made by a company called Alpha Technologies. The person you'll want to speak with is Jeff Thompson 1-630-886-4378. You can tell him Tony Drummond from Classic Color sent you. He may be able to help you with this issue and also open your eyes up to a really cool product. The ink has a wide gamut and also reduces typical dot gains that you see with conventional processes.

 

[Colin Gilham]

Thanks to all for the input so far.

I suppose I'm referring more to drying than scuff/rub. The ink on the sheet feels tacky and is very susceptible to marking and setting off under the guillotine clamp. At the same time though even when dry to touch it's prone to scuffing on post processes.

We do have ink saving software but not using it on every job; it's something that will help for some applications so I'll definitely look at using it more.

Regarding turnaround time we could be looking at anything as low as 3-6 hours after coming off press.

Upwards and onwards!!!

 

[Brer]

That's a quick turnaround for an uncoated sheet. Good luck. Let us know if you find anything that will work.

 

[Lukas Engqvist]

I would consider talking to customers. Also this is more of a problem if you care tuppence about the environment when choosing products.

As stated Ink saving is one way to do what you can. We usually offer them to use a semi coated paper if they insist on short turn around times.
Airing sheets sometimes helps, but it depends on the print run. If you need to finish the job printing 80% screened varnish may help not to smear colour during finishing, but there is the risk of getting moire on the magenta. (100% varnish will slow deep drying)

Some times the customer has to understand the limits of the real world rather that live in their concept of bullet time. If you look at production there is usually a long process before the job comes to you, and they need to see that sitting at a copywriters desk for two weeks because he is a "creative" will jeopardise the whole production if they expect chemistry to work outside the laws of nature.

Unfortunately this is partly due to an educational system which praises theoretical over practical knowledge.

 

[Cold]

Hello Colin,

When I look at different ink formulations I typically see these generalizations:

Hard Dry Inks - Slowest setting, glossiest, best rub resistance, suitable for synthetic substrates and particular uncoated stocks, such as index stocks.

Quick Setting Inks - Fastest setting, flatter, rub resistance will vary, suitable for all paper stocks, caveat on your dull coats.

"Slower Setting" Inks - Moderate setting, glossier, rub resistance typically better than quick sets, suitable for all paper stocks. A better match for jobs when not coating and dull-coat stocks.

I recommend that you ask your Ink Manufacturer for a good Quick-setting ink with the best rub resistance they can give you. This should allow you to turn your jobs much quicker and is hopefully set hard enough to take the guillotine after 6 hours.


Cold
"The truth I knew yesterday turned out to be my ignorance."

 

[Alois Senefelder]

Printing Inks - Drying OF !

Printing Inks - Drying OF !

Hello Colin and fellow Lithographers,


I suggest you read the PDFs I have posted,

Thread: Printing on Bond, Post: Drying Methods of Printing Ink,

Date: 06/06/2010

Regards, Alois

" From knowledge to competence is a great step --- from ignorance to competence an even greater one"

 

[HeroicKB]

I'm not a printing expert so this could be a terrible idea but....

Depending on the weight of your sheet is a all over aqueous possible?

We've actually done several projects on uncoated sheets (Finch and Cougar) with an all over aqueous coating (not for time reasons) and they've turned out great. We've run into a project on a lighter sheet (100lbs text) that began to warp the page slightly and it required the printer to seek out a low curl aqueous. It was a minor setback and a good learning experience. The piece came out amazing.

I'm told in general aqueous coatings decrease drying time.

This could be a terrible suggestion/thought for you but we've had success with it as a design/functional technique.

 

[D Ink Man]

Recommendation from Experience

Recommendation from Experience

I would recommend Kohl & Madden (Sun Chemical) Liberty Process Inks. These are very unique inks that set and dry fantastically on offset stocks. With heavy coverage (say 300%+) you can turn them around in less than 10 minutes. As for the uniqueness, they actually dry better with the least amount of oxygen introduced. If you print a 4 foot pile, let's say 28 x 40", you will find that the wettest sheet will be the top sheet of the load. Quite incredible but true. However there is one drawback. They are very expensive, 28 -35 usd$ per series. But if you experience instant set and dry, that cost it seems would be captured by the time savings. Give them a try. Let me know your experiences. Thank You. D

 

[Lukew]

Everyone seems to be recomending an ink to use. But very very important is both the Fountain solution and the ink.
Glycols Glycols Glycols --- Rid your fount from these and experience faster drying...
If you use a fountain solution or alcohol substitute that is full of specific glycols don't expect fast drying..
Do a bit of reading on what a lot of uses the mainstreme glycols that are found in most founts are used for in other industries and you will see that they have no place in a fountain solution if you want fast drying.

Sun Chemical in conjunction with Man Roland have apparently develeped a new super fast drying ink that can stay in the duct over night.
SUNLIT Titan,
Claims that it is touch dry in seconds and dry to back up in under 2 minutes. (Doesn't say what uncoated dry times are like though)

You guys in the USA are lucky enough that you have a company there that has built a fountain solutin & ink to work in harmony to give added ink mileage & faster drying.

 

[Brer]

Colin,
What did you do to resolve this issue?

 

[david.young]

Interesting discussion but I gotta ask. Can this be run on a Indigo or similar digital equipment. We have some larger runs on our Indigo and while the balance of the job is still running we can start cutting and folding the first lifts off the press.

Dave