Paints

2 Pages 620 Words

· Definition of Paint:
The term “paint” and “ surface coating” are often used interchangeably. Surface coating is the more general description of any material that may be applied as a thin continuous layer to a surface. Painting is distinguished from other forms of surface treatment such as electroplating, anodizing, and the lamination of the polymer film onto a surface. Paint is used to describe pigmented materials as distinct from clear films which are more properly called lacquers or varnishes.
Paint is defined as “thin coatings applied to surfaces in liquid form, which gradually dry to become gradual solids”.

· Purpose of Paint:
The purpose of paints and surface coatings is two-fold:
1. Aesthetic Purpose
2. Protective Purpose
3.
· Composition of Paint:
èVehicle (Continuous phase):
These are the components that give the paint a spread able body:
1. Binder:
· Description:
· Typical Function:
-Provides the basis of continuous film, sealing or protecting the surface.
-Bind together Paint or clear finish constituents
-Convert liquid coating into solid film
-Provides liquids with adhesive properties
-Gives water resistant properties
· Criteria for selection:
-method of application &cure
-nature of substrate
-conditions of use
· Types:
1. Drying oils:
2. Resins:
-Natural
-Synthetic
-Oleo: a combination of oil and resins
3. Polymers:


2. Solvent/ Diluents:
· Description:
-It is a colorless liquid incorporated in the paint
-It is the means by which the paint may be applied
-When the liquid does not dissolve the binder, it is called a diluent
-It plays no long-term role in the paint film performance
-Recently it is very rare that a single solvent be acceptable, and so mixtures of solvents are used.
-It is avoided in a small number of compositions such as powder coatings and 100% polymerizable systems. In the polymerizable case a polymerizable monomer plays the role of solvent...