Which raw materials would you recommend for forced drying paints for polyvinyl chloride surfaces ?
The choice will primarily depend on whether the PVC is in its plasticised or unplaticised form. In the former case, the paint must match the flexibility of the substrate but must also be unaffected by possible platiciser migration.
Adhesion of he paint filmnot only depends on whether or not a suitable paint has been chosen but whether the surface is absolutely clean and free from lubricants from the moulding process. These should first be removed, e.g. with a mixture of benzene and isopropanol.
Recommended resins are those that crosslink through oxidation, e.g. alkyd resins. Acrylic resins have also proved successful, especially in combination with vinyl chloride copolymers. ood result have also been achieved with two-pack polyurethane paints, especially in view of the fact that their curing temperature can be adjusted in accordance with the heat resistance of the PVC material.