- 2070 Bhadra · 2.5 marks
Requisites of good paints; varnish
Short answer
Good paint spreads easily, dries to a hard tough elastic film that adheres well, resists weather and chemicals, and is cheap and non‑toxic. Varnish is a transparent solution of resin in drying oil or solvent, containing no pigment, used to give a glossy protective film on wood and over painted surfaces.
Mention the requisites of good paints and write about varnish.
Requisites of good paints
- Easy to apply, with good covering power.
- Dries quickly to a hard, tough and elastic film.
- The film adheres well and does not crack or peel.
- Resists weather, water and chemicals, and has a lasting colour.
- Cheap and non-toxic.
Varnish
Varnish is a homogeneous solution of a resin (natural: shellac, copal, amber; or synthetic) in a drying oil or a volatile solvent such as turpentine or alcohol. It contains no pigment. On application the solvent evaporates and the oil dries to leave a transparent, glossy, hard protective film.
- Types: oil varnish (resin in drying oil + turpentine), spirit varnish (shellac in alcohol), water varnish.
- Uses: wooden furniture, doors and floors, and over painted surfaces to protect and brighten them.
✓ Answer checked by Claude Opus 5.5 (high effort)
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