---
title: "Paint requisites and types of paints"
subject: "Engineering Chemistry"
chapter: 8
key: "semester_2/engineering_chemistry:paint-requisites"
source: https://www.bctengineer.com/q/semester_2/engineering_chemistry/paint-requisites
site: BCT Engineering
---

# Paint requisites and types of paints

Engineering Chemistry · Chapter 8: Lubricants and Paints

- Asked in: 2073 Bhadra, 1+2+2 marks
- Video: [Paint -  Purpose & Characteristics  | By Supriya Mam | Ganesh Academy](https://www.youtube.com/watch?v=07lpM6dwMVA) — Ganesh Academy
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_2/engineering_chemistry/paint-requisites
- Whole chapter: https://www.bctengineer.com/md/semester_2/engineering_chemistry/chapter-8

## Question

What is paint? What are the requisites of good paint? Show your familiarity with the types of paints.

## Short answer

Paint is a mechanical dispersion of pigment in a drying oil with thinner, drier and additives. A good paint spreads easily, dries to a hard elastic film that adheres well, resists weather and chemicals, and is cheap and non‑toxic. Types include oil, enamel, emulsion, anticorrosive, cement, bituminous, aluminium and fire‑retardant paints.

## Answer

**Paint** is a mechanical dispersion of pigment in a drying oil with thinner, drier and additives, used to protect and decorate surfaces.

#### Requisites of a good paint
1. Easy to apply, spreads uniformly with good covering power.
2. Dries in reasonable time to a hard, tough, elastic film.
3. The film adheres well and resists cracking and peeling.
4. Resists weather, water, chemicals and heat; non-fading colour and gloss.
5. Non-toxic and cheap.

#### Types of paint
- **Oil paints** (pigment in linseed oil) for wood and walls.
- **Enamel paints** (pigment in varnish) give a hard glossy finish for metal and machines.
- **Emulsion paints** are water-based, used for interior walls.
- **Anticorrosive paints** (red lead, zinc chromate) for steel structures.
- **Cement paints** for rough outside walls; **bituminous paints** for underground pipes and wet places.
- **Fire-retardant and aluminium paints** for special uses.

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. What is paint?
   A. A clear solution of resin in volatile solvent with no pigment
   B. A mixture of cement and pigment in water
   C. A dispersion of pigment in a drying oil with thinner, drier and additives, forming a protective, decorative film
   D. A solution of bitumen in a solvent
   Answer: C. Paint is a mechanical dispersion of pigment in a drying oil (vehicle) with thinner, drier and additives; it dries to a thin film. (Key point: Definition of paint)

2. Which of these is a requisite of a good paint?
   A. Dries to a hard, tough, elastic film that adheres well
   B. Dries to a soft film
   C. Peels easily for repainting
   D. Fades quickly to look natural
   Answer: A. A good paint forms a hard, tough, elastic, well-adhering film. (Key point: Requisites)

3. Which paint type gives a hard glossy finish for metal and machines?
   A. Emulsion paint
   B. Cement paint
   C. Enamel paint
   D. Bituminous paint
   Answer: C. Enamel (pigment in varnish) gives a hard glossy finish. (Key point: Enamel type)

4. Where are bituminous paints used?
   A. Underground pipes and wet places
   B. Interior walls
   C. Wooden furniture finishing
   D. Decorating ceilings
   Answer: A. Bituminous paints suit underground pipes and wet places; cement paints suit rough outer walls. (Key point: Bituminous paint use)

## Related in Engineering Chemistry

- [Requisites of good paints; varnish](https://www.bctengineer.com/question.md?key=semester_2%2Fengineering_chemistry%3Apaint-requisites-varnish) — Engineering Chemistry, chapter 8
- [Paint and requisites of a good paint](https://www.bctengineer.com/question.md?key=semester_2%2Fengineering_chemistry%3Apaint-requisites-short) — Engineering Chemistry, chapter 8, asked 2×
- [Enamel; requisites of paints](https://www.bctengineer.com/question.md?key=semester_2%2Fengineering_chemistry%3Aenamel-paint-requisites) — Engineering Chemistry, chapter 8
- [Characteristics of good paints](https://www.bctengineer.com/question.md?key=semester_2%2Fengineering_chemistry%3Apaint-characteristics) — Engineering Chemistry, chapter 8, asked 2×
- [Good paint characteristics; painting galvanized iron](https://www.bctengineer.com/question.md?key=semester_2%2Fengineering_chemistry%3Apaint-galvanized) — Engineering Chemistry, chapter 8, asked 2×

## Related in other subjects

- [Paints, oil paint ingredients, painting woodwork](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Apaints-characteristics-066bh) — Building Technology, chapter 9
- [Characteristics of a good paint](https://www.bctengineer.com/question.md?key=semester_3%2Fcivil_engineering_materials%3Acharacteristics-good-paint) — Civil Engineering Materials, chapter 9