2 DefinitionThe fluid prepared by dissolving a base in a vehicle (carrier) along with coloring pigment is known as paint.Base materials – White lead, red lead, zinc white, etcVehicle (carrier) – Linseed, oil, nut oil, water etc.Coloring pigments – blue, black brown, green etc.In addition to the above ingredient of a paint solvent, drier are also used to make a standard paint.
4 Functions of Paints: To protect the surface from weathering effects. To prevent the decay of wood.To prevent corrosion of metallic surfaces.To provide colorful, pleasing and decorative appearance.To cover the incorrect surface of masonry and concrete works.To provide a smooth surface for easy cleaning.
6 Oil paints:The paint in which raw or boiled linseed oil is used as a vehicle is known as oil paints. These paints essentially consists of a base, vehicle and pigment.Base:A finely divide solid material providing body to the paint.Ex: white lead, red lead, oxide of iron etc.Vehicle:The liquid which carries the solid material is known as vehicle. Ex: linseed oil, nut oil, tung oil, etc.Pigment:Pigments are in various colors like White, Black, Blue, Green, Red, Yellow, etc.
7 Properties: These paints are cheap. These paints are easy to apply. It possesses good opacity and low glossIt is generally applied in three coats (prime coat, undercoat and finishing coat).
8 Uses: These paints are mostly used for decorative works. These paints are used for wood and iron works.
9 Enamel paints:The paints having white lead or zinc in a small quantity of oil and mixed with petroleum spirit are known as enamel paint.
10 Properties: They are very good quality paints They form a hard and impervious surface on dried.They are not affected by water.They are resistant to steam, fume etc.It dries slowly and forms hard and durable surface.
11 Uses:They are used for protecting timber and other wood based product.They are used for both external & internal works.They are generally used for painting doors & window frames.
12 Emulsion paints:The paints consisting of polyvinyl acetate and synthetic resins as binding material are known as emulsion paints.
13 Properties: These paints are easy to apply and dry quickly. The surface of these paints can be cleaned by washing with water.The color of the paint is retained for long period.
14 Uses:These paints are normally used for painting steel and wood works.
15 Distemper:Distemper are decorative paints for walls and ceiling, composition of distemper:1.Base 2. Carrier 3. Color agent 4. Size. Distempers are available in powder form and also in paste form.Powdered distempers are known as dry distempers and paste forms are known as oil bound distempers.
16 Uses: They are used on cement concrete, stucco, brick surfaces. They are good for external exposed situations.
17 Cement paintsThe paint which consists of cement and hydrated lime mixed with coloring pigment is known as cement paint.
18 Properties & Uses This paint provides a smooth mat finish. It provides a hard, durable coat,The surface painted by this paint can also be washed.It can be applied over new damp wall surfaces.UsesThese paints are used in wall surface, ceiling, etc.These paints are commonly used in residential & public buildings.
19 Aluminium paintsThe paint consists of aluminium powder suspended in spirit varnish or oil varnish is known as aluminum paints.
20 Properties & Uses Properties: These paints are heat resistant. They have high electrical resistance.They protect the surface from sea water corrosion.They possesses high covering capacity.Use:These paints are suitable for protecting metal work.Example gas tanks, hot water pipers, marine pipes & oil storage tanks.
21 Bituminous paintsThis paint consists of asphalt or bitumen dissolved in oil or petroleum are known as bituminous paints.
22 Plastic paintsThe paint consisting of required from of plastics are known as plastic paints.Properties:These are finest type of paints.They provide a durable attractive surface on drying.Uses:These paints are mostly used in cinema hall, auditorium, showrooms etc.
23 Process of painting: Definition The art of applying number of coats of paint on any surface is known as painting.
24 Defects in painting: Fading: The gradual loss of color is known as fading. This may be due to the effect of sun rays.Flaking:Due to the poor adhesion, paint may peel off from the surface.Blistering:This is caused by water vapour, which is trapped behind the painted surface. It may occur due to imperfect seasoning of timber.
25 If the horizontal surface is too thickly painted wrinkling will occur. BloomThe formation of dull patches on the finished surface is known as bloom. It may occur due to bad ventilation or defective paint.Running:The paint runs back and leaves some areas of surface un covered. This defect occurs when surface is too thickly painted sagging will occur.WrinklingIf the horizontal surface is too thickly painted wrinkling will occur.
26 FlashingThe patches seen on the painted surface is known as flashing. It may be due to poor workmanship, weather action, or poor quality of paint.Grining:If the opacity of the final coat is in sufficient the back ground of the painted surface is clearly visible, this is known as grinning.
27 Remedies: Preparation of the surface is very important. Good quality of paint should be used.Skill worker should be engaged.Application of paint should be done according to the specification.The second coat is applied only after drying of first coat.
28 The End … Thank you … Department of Civil Engineering, M.S.P.V.L Polytechnic College ,Pavoorchatram.