Linseed oil

Flaxseed oil can be polymerized and this reaction is exothermic, a rag soaked in this oil can ignite on its own. Due to these polymerization properties, linseed oil is used alone or in a mixture with other oils, resins and solvents as an impregnating agent and varnish in wood treatment, as a pigment binder in oil paints, as a plasticizer and hardener in sealants and also in linoleum production.

Wood surface treatment
If linseed oil is used in the surface treatment of wood, it dries slowly and shrinks slightly when hardened. It does not cover the surface like varnishes, but soaks into the (visible and microscopic) pores, leaving a clear but not glossy surface that shows the texture of the wood. Wood treated with linseed oil is resistant to creasing and scratching, it can also be easily repaired, but the surface is not as hard as with modern varnishes and the wood slowly absorbs moisture when left wet. Soft wood is protected against crushing, but it needs repeated application several times and also a much longer drying time compared to hard wood. Garden furniture treated with linseed oil can be attacked by a fungus. Oiled wood may be yellowish and may darken over time.
Flaxseed oil is traditionally used for surface treatment of weapon stocks, obtaining a very fine surface can take months. Several coats of linseed oil are the traditional protection for willow wood cricket bats. Flaxseed oil is also often used on billiard cues, as a lubricant / protection for wooden recorders and fujars, and instead of epoxy resins for modern wooden surfboards. The oil is suitable for the treatment of objects that come into contact with food or mouth.