Before the process of pad printing begins, it is important to know what kind of cup you should (and should not) be using to mix your ink. Mixing solvents with ink is a very important part of the pad printing process, as it to enables the ink to transfer and dry quickly. However, solvents are strong chemicals that will melt right through certain materials. If you’re mixing cup is made of such a material, your going to have a problem before you even get started.
What types of cups to avoid
- Styrene – weak organic compound that most solvents will melt through.
- Polystyrene foam (e.g. Styrofoam) -breaks down when exposed to a solvent.
- Wax coated – wax can mix in with solvent and affect adhesion.
- Ring cup itself – doesn’t allow for easy mixing and can result in costly damage to the cup as well.
What types of cups work well
- Waxless paper – cheap, disposable and durable material that won’t be damaged by a solvent.
- Polypropylene – strong, thermoplastic polymer that will also stand up to a solvent.
It is also highly recommended that you test the cup if you have any doubts, by allowing some thinner to sit in the cup for about an hour.
Lastly, we do not recommend reusing any cup. It is time consuming to clean and you risk leftover ink and material breakdown, both of which can affect your ink mixture.