Drying of Acrylic paints

About drying of Acrylic Colors.

Types of Drying
1) Surface drying: This is the first stage of drying, where a skin gets formed over the surface because the moisture, stored in underlying layer, are no longer able to keep the film/surface wet. This is also called as "dry-to-touch". Thin layers attain this stage in seconds while think layers would have to wait little longer.

2) Internal drying: This is the time required for every layer to dry and is more important than Surface drying. Time for this varies and could take hours. I have observed that color mixed with Gels or Pastes takes lot longer to dry, and show different color when dry.

Temperature:-
-Does not dry well at temperatures below 48F
-While using Hair-dryer, keep the heat low.

Substrate and drying:-
Substrate is the painting surface and its nature affects the time taken by paint to dry. An unsealed the surface/substrate like paper or canvas could accelarate drying of Acrylic color. By sealing the substrate -with Golden Soft Gel etc...- one can reduce the drying time.

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