I visited a plant that had many quality problems, in particular, slow ink drying, scuff issues, chalking, low gloss, burn out, excessive dot gain, ragged dot structure and a host of others. The pressroom was clean and orderly, prep was immaculate and pressmen seemed knowledgeable. So what was causing all the problems?

After looking over the plant, I found the ink room and what a surprise — 30 brands of ink, some of which dated back to 1992. A can of ink for conventional sheetfed has a shelf life of one year, web offset inks about six months, and EB and UV about three to six months if kept in plastic containers. Ink that is vacuum sealed from the manufacturer has a life of about five years in an unopened can.

To top it off, the printer stored all the old inks for his duplicators in cardboard boxes — this is not good. The tragic part of this visit was that all the leftover ink was never expensed to the job but was returned to the ink room at full cost. No wonder they did not wish to throw out any ink.

Here are a few ideas for managing ink:

• Good estimating of quantity is needed — use your ink company.
• Expense all ink ordered for the job to the job.
• All UV or EB ink should be stored in plastic containers.
• Sheetfed ink returned to the ink room should be in cans, spray applied and with a lid on it.
• Purchase a Mixmaster software system to allow you to work off old ink into new colors.
• Ink that cannot be used should be made into black and used on commodity jobs.
• Keep ink on the shelf that is within shelf life.
• Have one person mix ink; don't let each press operator mix ink.
• Do not mix brands of ink. If at all possible, buy ink from one ink company.
• All ink additives should come from the ink company or be blessed by the ink company.
• Keep the inventory small — ink companies are wonderful about on-time delivery.

When you manage your ink well, many problems will go away.

Editor's note:
Ray Prince's “Tech Thought” series appears each month in AP's “New Products” section. See www.americanprinter.com.
Don't miss his new podcasts at www.napl.org.

Raymond J. Prince is a leading expert in pressroom technical and operational issues. He recently joined NAPL (Paramus, NJ) as vice president and senior consultant, operations management. Contact him at (605) 941-1492 or e-mail RaymondJ.Prince@aol.com.