Magenta blinding on silvermaster - stumped

[CostaRicaPrinter]

Hello fellows,

I'm new to the forum, and I see lots of good discussions! Thanks to everyone who shares their knowledge and experience.

I have a small book publishing operation in Costa Rica. We recently brought in a Printware silvermaster platesetter, and have just loved it (we were using plastic laser plates or metal plates and negatives before). HOWEVER - when doing 4 color work, we have had consistent problems with magenta plugging up fine screens, and drying out on the plate.

Our press is an AB Dick Century 3000, motorized dampening, alcohol system. We are using Kerley ink, but have tried other inks as well. We have a plethora of fountain solutions - with and without alcohol, and have tried them all. The best we can manage is with Baseline Pink and alcohol - but we do around 1,000 sheets and the plate starts drying out and the screens plug up.

I've read some posts, and I see that magenta often presents a problem, especially with the black plates. Any advice will be well received!

 

[Cold]

Before taking any further steps, I strongly recommend de-calcifying your roller train.

 

[CostaRicaPrinter]

Magenta ink

Magenta ink

Hello Cold,

We did a deep clean - actually several times. We use Bottcher cleaner, and used vinagre with warm water. We don't have ANY problem with any other ink - the press prints really well. But since we've gone to the silvermaster plates, magenta gives us a headache.

Thanks!

CRP

 

[Bob Peterson]

It sounds to me like you are emulsifying the magenta. Try using a magenta with a heavy body, in a pinch you might try adding 10% of a heavy binding varnish.

 

[Cold]

Ok, if you are confident calcium is not a factor, I suggest:

Let's eliminate the unit, switch the cyan and magenta units for a job(s) that can stand the trap difference. Does the problem follow the magenta?

 

[Richard]

Hi: after looking at a century 3000, it looks very similar to the 9985 I currently operate.
And I have to admit, I encountered exactly what you describe. Except I was doing a two color job: black and magenta. The magenta image was finely screened. It was the image of a machine part, and was supposed to look shiny, in magenta, after 20,000 shts. I found that the magenta is very soft. I set the ink fountain low, evan off at some points in the run. I reduced the blanket to impression pressure, maybe even at the lowest it would go. And, there is a good chance I removed one of the three ink form rollers. Yes, you can remove the biggest one without a problem. This is why your screen is plugging in. Two ink form rollers may be all you need. Pull the third form out. Just open the gate, open the op. side panel, and try it without it.

richard.

 

[Richard]

Hi: after looking at a century 3000, it looks very similar to the 9985 I currently operate.
And I have to admit, I encountered exactly what you describe. Except I was doing a two color job: black and magenta. The magenta image was finely screened. It was the image of a machine part, and was supposed to look shiny, in magenta, after 20,000 shts. I found that the magenta is very soft. I set the ink fountain low, evan off at some points in the run. I reduced the blanket to impression pressure, maybe even at the lowest it would go. And, there is a good chance I removed one of the three ink form rollers. Yes, you can remove the biggest one without a problem. This is why your screen is plugging in. Two ink form rollers may be all you need. Pull the third form out. Just open the gate, open the op. side panel, and try it without it.

richard.

 

[CostaRicaPrinter]

Magenta

Magenta

Hello Cold - yes, the problem follows the magenta. We have an ink - solution - plate issue.

Richard - our problems are with fine screens also. Why do you think that using less rollers helps the problem? We did reduce blanket pressure, and helped a bit.

Bob - we actually found that REDUCING the body of the ink helped. We have a pretty cool environment (air conditioning), so heat is not an issue. When we softened the ink, we could at least get through the run (after cleaning the plate a few times).

I spoke with our supplier of the silvermaster plates, and he recommended a product by Allied called DTA. Anybody ever use it? It is supposed to help with wetting.

Thanks fellas! I think I'm making progress at least in understanding the problem http://printplanet.com/forums/images/icons/icon12.gif

CRP

 

[RGPW17100]

We used to have the same problem. Our ink company put a varnish in to help fight the water. In a pinch you could use Rubine red instead. It is a bit stronger then Magenta but may be a stiffer ink.

 

[Asures]

With regard to Polyester plates, they have always been a challenge.

The problem that you are having is that on the polyester plate in particular, there is no actual grain for the non-image area to effectively carry an even film of water. It is actualy a silica coating that yes, carries water...but not very well. Rather frustrating to us ink guys - actually!!

As a result, once you start running, that non-image area water is being absorbed into the stock and you end up running too dry - hence screens start plugging, and you see scumming on the lead edge of the plate (that everyine calls "Toning"). You run your water up to keep the screens clean and before you know it, it has whacked your ink by over emulsifying the color giving problems.

There is actually a product that can help made by Silvermaster. It is called "Silvermaster SLM-Ao2" that is designed to be added to any fountain solution. It helps by allowing your fountain solution to bond to the non image area of the plate and carry water evenly. That is where Allied DTA came from but was recently discontinued due to the short shelf life. SLM-Ao2 will keep your screens clean and eliminate a good majority of the problems you are describing. Take a look at the link and info below.

Mitsubishi Imaging (MPM), Inc. - Graphic Arts

You can talk to your supplier and specifically order that product. Do not be alarmed by the foam that it creates once added.

Good luck to you.

 

[CostaRicaPrinter]

Dry plates

Dry plates

Hello Aaron,

Funny you should mention the SLM solution! Just today I was asking around, and was offered that as an alternative. HOWEVER - I am not using Mitsubishi plates, but the Agfa plates. Do both types of silvermaster plates work similarly? I believe that they are not compatible for the platemakers. But if I can used the SLM on my Agfa plates, I'll give it a try. The only problem is that they want almost $30 a quart for it here in Costa Rica! Yikes.

Please advise.

Bill Green

 

[Asures]

It really doesn't matter what black surface polyester plate you use. The concept and non-image area surface is the same.

As for the $30.00 a quart, that sounds about right in price. You are only going to add 1/4 - 1/2 and oz. to a mixed gallon for fountain solution. Worst case scenerario, 1 quart of the "Magic Potion" that has the potential to cure and eliminate every problem you can imagine with that plate (I'm probably over exaggurating just a bit) can be diluted with 64 gallons of diluted fountain solution.

$30.00 investment or rerunning jobs because quality has been compromised?

You may be dealing with a Miami distributor in purchasing your plate material. They might have better access to the SLM Ao2 product than Sommerus and or Serfgrafic. I am familiar with your market and who the local suppliers are and would suprised if either carried it locally.

There is a similar product also available from Prisco. Their product is Prisco SMA - Silvermaster additive. See the attached link for their item code/product description. I know they have an office in Miami.

http://www.prisco.com/content/library/media/documents/PriscoNet/Document_Library//c412_usa_pbp.pdf
Best of Luck!

 

[Green Printer]

Get in contact with bestchemsupply ask for the universal fountain solution. I have seen this used on ABDICK, Hamada, Ryobi, Sakurai, Heidelberg, Solna,Meihle, Didde, Hamilton, Shinohara and many other presses running poly plates at 175 line screen and getting up to 50,000 plate life. No hand prewetting. On 1 or 2 color jobs the second sheet is good on 4 color the 5th or 6th. I would suggest using the complete system of fountain solution and ink for the best results. These products were engineered to work together. This link gives a users view BESTCHEM+SUPPLY customers benefit from Habitat Products - WhatTheyThink.

A problem free user.

 

[BillJ]

The century 3000 is not the same as the 9985/3302. It has a larger ink train and a motorized dampener that was designed by AB Dick. If properly set up it can out print the 9985 as far as coverage and screening. The dampeners are very sensitive and takes some skill and patience to stripe. The water rollers also only last 1-2 years. They can still be striped but will not carry water correctly.

OA2 will probably help. It has fine silica particles which creates an artificial grain on the plate. Mitsubishi also makes a fountain solution called OD-50 that works very well in continuous dampeners. If you look at the price it looks very expensive, but it is very concentrated. Usual mix is 1.5 oz/gallon.

 

[Dan Roll]

You mentioned that reducing your ink helped and this has always been my observation when working with silver-halide image plates, that often the image area is not adequately ink-attractive to run reliably on small presses unless the ink is somewhat liquid. Whenever there is trouble with this type of plate people usually focus on the background (like adding amorphous silica to the fountain solution) but adding some linseed oil or chinawood oil to the ink usually helps a lot with screens and solids and I have seen this approach lead to making it much easier to keep the background clean.

 

[CostaRicaPrinter]

Magenta printing

Magenta printing

Hello all - lots of good comments! My ink provider recommended linseed oil as well, so that will probably be a help. And I'm trying to find the availability of the other solutions mentioned.

We finished our run, and are now varnishing and binding, so it's going to be a little while before I run magenta again. I appreciate all the input! I feel much better armed.

And just a plug for the homely AB Dick Century 3000 - everyone says it's a terrible press and you can't print with it, but there are Century's out there with many millions of copies (like mine) doing some pretty fine work. Great screen quality, great registration - just finicky on the magenta silvermasters!!! But we are going to get that fixed too. Thanks for all the help!

Bill G.

 

[CostaRicaPrinter]

Additives

Additives

Hello Aaron,

I just re-read the posts. It sounds like you know Costa Rica! We have a perennial problem with supplies - very limited. But I am on the "look-out" now, and am better informed of what I need.

I'm grateful to all who have given such expert advice!

Bill G.

 

[CostaRicaPrinter]

Update on magenta problems

Update on magenta problems

Hello all,

Here's an update. We are using small amounts of the solution SLM-Ao2, and we have softened the magenta ink with linseed oil. We have done many runs now of some really heavy magenta and some fine screens. No plugging! In fact, we are running with virtually no alcohol also. So between softening the ink and using the SLM-Ao2, we are in business!

Thanks everyone for the good ideas!

Bill G.