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Test Your Offset Printing Ink For Bleed




It's a simple test for your offset printing ink that any pressman can do with limited tools.  It will tell you how compatible your ink and fountain solution are.  It will also tell you why you may have scumming problems - or more correctly tinting or toning problems.  It is a test that the chemists at major ink companies such as Sun Chemical or Flint will do and if you would like to speak intelligently with them, they will know this test.  Quite simply, it will help you troubleshoot your ink.


The Ink Bleed Test
The only things you need to perform this test are shown in the picture above.  Here is what you need:

  • A small sample of the ink you are currently running.
  • About half a cup of your mixed water and fountain solution.
  • An empty plastic bottle.

To perform this test, do the following:

  1. Cut out the bottom of a plastic bottle (about the bottom 2 inches)
  2. Put a small dab of ink in the center of the ink you want to test.
  3. Put your current running fountain solution and water mix into the cup so that it is about the same height as the ink.
  4. Time how long it takes before the ink bleeds into the water.
Step four can takes minutes or days.  For our ink, we put it in for a couple of days and the ink does not bleed.  However, take a closer look at our test below from above.  




Notice the very light colored pigment that is bleeding into the water.  This only took about two minutes.  The reason is because we used distilled water in this instance.  GATF recommends using distilled water as it is much more aggressive.  So what counts when you use distilled water is how many minutes it takes to break down the ink as it is in the picture above.


What It Tells You
What appears to be a scumming problem, may actually be tinting.  In other words the water may be breaking down your ink and you are constantly fighting what appears to be an ink and water balance problem.  When troubleshooting a problem like this, it is good to perform this test.  If you follow these steps, you can communicate intelligently with your ink supplier.  At the very least, your water and fountain solution mix should not break down your ink as it does in the above picture.  If it does, call your supplier.  He will likely want to do his own testing which may not amount to much more than what you have already done.


Give it a try.  Leave me a note and let me know what you find.  If you think this test is useful, recommend it or "Like" it on Facebook.  It's a great little troubleshooting tool for any pressman.


Related Articles
How to Measure Your Ink and Water Balance Window
Ink and Water Balance Concepts

3 comments:

  1. Anonymous4:39 PM

    I have done this test with InkSystems inks. I have done the magenta cyan and yellow. Magenta took about 24 hours with fountain solution and it was floating all over the bowl. The cyan and yellow only took about 45 mins to start floting all over the bowl. Help me help them cause I have to run this stuff and I feel like Stevie Wonder playing the ink keys. Help very frustrated pressman

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  2. Hmmm. This test is more for troubleshooting tinting/toning issues. It sounds like you have a stability problem. We had something similar to what you described about 6 months ago. When running full speed for more than 20 minutes, the ink floated all over the place. The manufacturer (Flint) had changed the ink vehicle without informing us. We had them change it back and all is better. The water was backtracking to the fountains and waterlogged the ink. Talk to your ink supplier. They're always looking for shortcuts and you may the victim of one.

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  3. Anonymous1:22 PM

    We are having tinting toning and stability problems and we have has this right from the start with this ink they have a nice implant but we have a real hard time running the ink we just changed to them from superior which was nice to run this new ink is all headaches

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