Moderator:
Sarah:Topic: Paint additives for speeding up drying. What are they? where do you get them? When should you use them? When shouldn't you use them?
Kent Smith:I used them in maroons and dark blues that didnt want to dry in the humid weather here. You have to be very careful as the more you use and the faster the paint dries, the more brittle and easy to scrach off, it becomes.
The original Japan Dryers were a blend of high grade solvent, varnish paste base, and white lead. They were used to advance the curing process in root resin based coatings and were added at the factory at about 1 to 3% by volume. Under adverse drying conditions or after the product had settled over a long period, once could add an additonal 3 to 5% in the field. Adding more than that amount would act as a heavy metal blocker so that the cure process could not begin. Cobalt has been used as a lead substitute for some time and does not accelerate the process as quickly. This blend also must be used in smaller percentages, perhaps not exceeding 3% overall. Cobalt also has no resin so it does not easily attach itself to the resin in the coating.