ink for basketball black lines

[kevin_hp]

I am working in a sport balls production factory . we have a problem with our basketball balls black lines ink . this ink remove easily after use . what can we do ?

 

[btrueblood]

a) Has the ink performed well in the past?
b) Have you contacted the ink manufacturer to see if they changed something?
c) Have you looked at the production process to see if they have changed something? Maybe the balls are being moved/handled too soon after de-molding, and the ink is not yet fully cured?

What is the outer orange layer of the ball made of? Find an ink that:
1. adheres well to the orange layer
2. does not dissolve or otherwise react to skin oils/sweat
3. is flexible

I'd think there are pvc-based paints that would work.

Edit: hmm, question d) how/when/where is the ink applied (my assumption is that it's applied to the mold surface, but I suppose it could be applied in a post-molding step...)