Hello Keyvan,

I'm not into vulcanized rubbers, but in general I know 4 ways (sorted by effort needed) to approve adhesion of an ink:

1) Simplest way: Clean surface using a solvent like alcohol prior to applying the ink.

2) Add a solvent to your ink which is able to dissolve the material you want to apply the ink onto. I don’t know a proper solvent for your rubber.

3) corona, plasma, high-power UV-light or flame treatment of the surface prior to applying the ink. This removes organic contaminations and activates chemical bonding possibilities of the surface.

See e.g. https://doi.org/10.1163/156856193X00600

4) Pre-coat the area where the ink should be applied to with an intermediate layer to improve adhesion. Most often they are called “Adhesion Promotion Primers” you have to search for one for rubber. First hit when I googled: http://reltekllc.com/rubber.aspx

Perhaps you can mix the primer with your ink.

Good luck!

Dear Keyvan,

if I paint my rooms, I have a similar problem. It happens that the color peels off.

To avoid this I paint an interfering layer. This is a transparent and elastic material and holds on the substrate and on the color. In semiconductor technology you have the similarly problem to connect substrates with conductor lines. An intermediate layer helpes (in german Haftvermittlungsschicht).

With Regard

R. Mitdank

A black isocyanate coating should have excellent adhesion and will cure with the moisture in the humidity (i.e., moisture curing urethane).