In paints, methylated spirit, neptha and turpentine are used as:
Correct Answer:
C. Solvent
🔬 Understanding the Role of a Solvent in Paint
A solvent (also known as a thinner or vehicle) is a volatile liquid component of paint. Its main purpose is to dissolve the binder and other solid components to create a smooth, liquid mixture that can be easily applied to a surface.
Solvent: The liquid that carries the solid components of paint (binder and pigment). It makes the paint workable and evaporates after application, leaving the solid, protective film behind.
Key Functions of a Solvent:
- Reduces Viscosity: It thins the paint, making it less thick and easier to spread.
- Aids Application: It allows the paint to flow smoothly from a brush or sprayer.
- Controls Drying Time: The rate at which the solvent evaporates influences how quickly the paint dries.
⚖️ Deconstructing Paint: Base vs. Binder vs. Solvent vs. Extender
To understand why (c) is correct, it's crucial to know the role of each main component in paint:
- (a) Base: This is the primary pigment that provides the body and hiding power of the paint (e.g., Titanium White, White Lead). It's a solid.
- (b) Binder: This is the "glue" that holds the pigment particles together and makes the paint stick to the surface. It forms the actual paint film (e.g., Linseed Oil, Acrylic Polymer, Resins).
- (c) Solvent: This is the liquid that dissolves the binder and allows the paint to be applied. Methylated spirit, naphtha, and turpentine are all classic examples of volatile liquids used for this purpose.
- (d) Extender: Also known as a filler, this is a type of pigment added to increase the volume of the paint and reduce its cost. It has low opacity (e.g., Barium Sulphate, Chalk).
💡 Study Tips for Paint Components
- Solvent Solves the Flow Problem: Remember that the solvent's job is to make the paint liquid and flowable. It "solves" the problem of the paint being too thick.
- The Evaporating Helper: The solvent is the only major ingredient designed to leave the party early. It does its job and then evaporates.
- Categorize by State: Think of the Base, Binder, and Extender as the "solids" and the Solvent as the "liquid" carrier.
- Associate Examples: Link specific examples to their category. Turpentine, Spirit, Naphtha = Solvents. Lead, Titanium = Bases. Oil, Resin = Binders.