General
- pigments - generally the same across all media
- carrier, or solvent or extender - preserves the finish liquid in the container and evaporates as the finish dries. Oft petroleum-based or synthetic materials; or linseed oil or water.
- binder, or resin - holds the pigment, protects the surface.
- lacquer, natural oils, shellac, and varnish
- Clear coat paint - Polyurethane based.
- Additives
- fungicidal chemicals.
- Chemical dryers (in case of slow drying linseed oil binders)
Clear finishes
Lacquer
- mostly acrylic; sometimes nitrocellulose
- usually has high solvent and VOC content
Natural oils
- Linseed oil from flax and tung oils are popular.
- they cure by absorbing oxygen and hardening rather than by evaporating solvents and simply leaving behind a binder.
- Some penetrate wood (eg linseed oil), others coat it as well (due to added PU type binders)
Drying time
- raw linseed oil has a drying time of about 3-7 days for each coat
- “Boiled,” “heat treated,” or “polymerized” linseed oil dry faster.
- Sometimes metallic drying/ siccative agents are added to cut drying time to a day.
India choices
- Airplane brand double boiled linseed oil has additives: lead, cobalt and zinc.
Shellac
- Shellac uses ethanol solvent made from corn.
- shelf life of only six months
- dries quickly, you can apply many coats in a short time—dust has less time to settle, which makes desirable results easier to obtain.
Varnish
- acrylic or urethane binder + drying oil