What is in the water-based paint that makes it stick? White glue! In paint manufacturing terms the product is PVA (Poly Vinyl Acetate). This is the same white glue you have used in school to make paper and wood stick together.
It is not an instant stick, PVA takes time to cure but when it does cure … You have an excellent bond to almost any sub straight. Gluing glass or plastic may be a challenge for PVA, however, I have done so with some success. I am not recommending PVA (White Glue) for ‘Non Porous surfaces’.
PVA (White Glue) looks white and when it completely dries it turns clear or in exact terms ‘Translucent’. That is why it works in the paint because PVA can be put in the paint with other ingredients and not have an effect on the color outcome of the desired product.
This is the simple answer to your question. However, in more technically advanced products the manufacturer may use more sophisticated resins. Sometimes this is a mix of PVA and a sophisticated resin combination to accomplish adhesion. Usually, these paints are fifty percent more in cost.
A wonderful trim paint that sticks and works well is Benjamin Moore, Advance Water/Oil Enamel. It is water cleanup and is a very hard finish. This paint does need at least sixteen hours to apply the second coat however it is worth it. The easiest and most smooth finishing is by spraying.
I use it in my painting business and the customers love how it looks and feels.
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