Today we learn What are the ingredients of a varnish? Describe the various types of varnishes
Ingredients of a Varnish
Varnish consists of the following:
1. Resin
Copal, lac or shellac and rosin are some of the commonly used resins.
Some other types of resin are amber, mastic, gum dammer etc.
2. Drier
Drier accelerates the drying process.
The commonly used driers are litharge, white copper and lead acetate.
3. Solvent
The type of solvent depends on the type of resin used.
For example, Linseed oil is used for amber and copal resins, turpentine is used for mastic, rosin type of resins, wood naphtha is used for some other varieties of resins etc.
Types of Varnishes
Various Types of Varnishes
According to the type of solvent used, varnishes are classified as:
1. Oil Varnish
Linseed oil is used as a solvent in this varnish.
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Linseed Oil for Oil Color |
Hard resins like amber and copal are dissolved in linseed oil and sometimes a small quantity of turpentine is also used.
Oil varnish dries up very slowly but forms a hard and durable surface.
2. Spirit Varnish
In this, the methylated spirit of wine is used as the solvent.
The spirit varnish dries up quickly but is not durable and is easily affected by weathering actions.
3. Turpentine Varnish
Here turpentine oil is used as the solvent and the resins used are of soft variety like mastic and rosin.
These varnishes dry up quickly and possess some light colour but are not tough and durable.
4. Water Varnish
Some of the resins like shellac are dissolved in hot water and a sufficient quantity of ammonia or borax or potash or soda is added.
These varnishes are used for varnishing maps, pictures etc.
FAQ 1: Which Ingredients of a Varnish increase Drying process?
Drier Ingredients of a Varnish accelerates the drying process.
FAQ 2: Which Types of Varnishes make surface hard and durable?
Oil varnish dries up very slowly but forms a hard and durable surface.