Any ideas how to stop ink peeling when the package is sealed?

Hello,

We print our gable top packages with flexo and we use a solvent based ink and wax (5%) but we face the problem of ink peeling when the package is sealed because of the scratches of the belts. We tried to increase the wax but it didn't works.

Can someone give an idea please?

Can you apply an over varnish or lacquer to the print to protect it.

Are you making the gable packaging for customers and printing some coding on the individual units?  Or, are you printing on cases for the individual units?

I'm thinking the first question....if that's the case can you use some type of dye to make an impression for lot / date coding?  I've seen this from other gable top paperboard manufacturers.  Others use the flexo printer in the process.

Check the Dyne level of the polycoated board. depends on the type of poly but should be at least 36 for solvent inks to properly adhere, ideally 40. Check with ink and board supplier for proper dyne level range.

Inform the board supplier of your process. They may not be aware of the need for a certain dyne level. 

The corona treatement is 40 but the problem is the ink 

replace the belts

Adding more wax probably makes the ink softer and thus more prone to peeling, scratching, etc.

So you either need to make the ink harder and/or use softer, smoother belts per reply above.

As suggested above, adding a clear coating my help.

If the belts are harder and rougher than the ink, they are going to  act like sandpaper, or act like tape (sticky side out).if the belts are tacky.