Screen Print World Ltd - @squeegee_and_ink have recently done a great video all about printing using puff inks. They created this t-shirt for their brand @blind_maggot using the AMEX Plastisol puff additive.
Speedball Screen Printing Puff Additive, 8 oz. : Amazon.es: Hogar y cocina
AMEX Plastisol Puff Additive to make prints rise | Screen Print World