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Paints: Mechanical dispersion of one or more pigment in a vehicle. The vehicle is liquid consisting of nonvolatile film forming material.
Pigment: Solid substance which is essential constituent of paint. It provides capacity, strength & desired color to paint. It also gives pleasing look. It gives protection to the surface by reflecting UV rays It increases resistance towards moisture.
E.g. White –Zn & Ti oxide
Red- Iron oxide
Green –chromium oxide
Pigment should be opaque, nontoxic, chemically inert & freely mixable with oil.
Vehicle: It is called as drying oil. It is film forming constituent of paint. These are esters of fatty acids generally present in animal & vegetable oil like linseed & soyabin oil
Functions: It supplies film -
- It gives toughness
- It increases adhesion
- It plays important role in water proofing
Thinners:
- Reduce viscosity
- To dissolve vehicle & additive
- Suspend pigment
- Increases penetration power
- Increases elasticity of painted film
- Due to the evaporation process film dries fast
Driers: Driers are oxygen carrier catalyst. It accelerates drying by oxidation, polymerization & condensation. Main function is to improve drying quality of film e.g. linolate & tungstate of Co & Mn.
Filler: Low refractive index material. It decreases cost & cracking with increasing durability.
Plasticizer: It increases elasticity & plasticity. E.g. Trycresyl phosphate
Antiskining agent: it prevents skinning & gelling