Plastisol is generally made by taking PVC powder and dispersing it into a plastisizer. PVC Free Plastisol would be plastisol made by some other type of plastic such as acrylic. Waterbased inks are based on water (up to 70-75%), not plastic or acrylic. The confusion may be due to the binders in waterbased ink being called "acrylics" but they aren't based on these binders, the primary component is water.
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