Surface coating industries

Surface

Coating

Industries

Surface-Coating Substances

• refer to any mixture of film-forming materials with the addition

of pigments, solvents, and other additives, which when applied

to a surface and then dried, will yield a thin film that is

functional and decorative in sense.

History

• Noah did even utilized a mixture of resinous derivative

called pitch inside and outside the ark which he latter

used as a waterproof.

• The early Phoenicians used the Tyrian purple, also called

as murex which was derived from tiny sea snails

colectively called Muricidae.

• Taong Tabon’s remnants of their figurative sketch on the

walls of caves employing limestones.

Surface-Coating Substances: Raw Materials

There are four basic raw materials necessary for the

production of coating substances:

1. Pigment

2. Resin

3. Solvent

4. Additive

Pigments

- are colored, organic and inorganic substances that are

widely used in coating industries as well as in ink, plastic,

rubber, ceramic and paper industries whose main function is

to impart color of desired tint and shade.

White Pigment

Lithopones

– is a mixed zinc sulfide- barium sulfate pigment that contains

about thirty percent zinc sulfide.

– are used in water-based paints because of their excellent alkali

resistance.

– The synthesis involves the following reactions:

BaSO4 + 4C BaS + 4CO

BaS+ ZnSO4 ZnS + BaSO4

•

Titanium Dioxide

– is regarded as the most important white pigment being utilized by

majority of industries today

– is marketed in two crystalline forms, anatase and the more stable

rutile.

– Anatase can be converted to rutile by heating to 700-950°C. TiO2

is widely employed in exterior paints and also in enamels and

lacquers.

Titanium Dioxide

– It is manufactured via the following processes:

Sulfate Process

Chloride Process

Chloride Process in TiO2 making

Sulfate Process in TiO2 making

White Pigment

Natural Black Oxide

- This contains 94- 95% Fe2O3. It’s a cheap pigment used in

primers for metals. It can absorb about 10-15 kg of linseed oil per

100 kg of pigment.

Natural Black Oxide

Precipitated Black Iron Oxide

- It has blue-black color and manufactured from a solution of-

FeCl2. The solution is taken in wooden tanks and ample amount

of lime water is added to it in order to precipitate iron.

Black Iron Oxide

Lampblack

- can be prepared by heating heavy mineral oils in a limited

supply of air. The soot is collected then from multi-compartment

chambers at regular intervals.

Lampblack

Ultramarine Blue

Phthalocyanine Blues

Ferrocyanide Blues

Fe4[Fe(CN)6]3•14H2O

Red Lead

Red Lead

Basic Lead Chromate

Basic Lead Chromate (PbCrO4 ∙ Pb (OH)2 )

Cadmium Reds

– a synthetic, inorganic pigment mostly made up of cadmium

sulfoselenide.

– Cadmium red is low in oil absorption with slow drying rate. It is

suitable for all media except for exterior designs.

Cadmium Red

Ochre

Ochre

Chrome Yellows

Chrome Yellow

Chromium Oxide Green

Chromium Oxide Green

Phthalocyanine Green

Phthalo Green

Industrial Resin

- these are synthetic polymers that have adhesive, film-forming

and useful reactive properties.

- bind with pigments in order to form a continuous film that is

important for aesthetic and protective purposes.

Industrial Resin

• Shellac

• Phenolic Resin

• Alkyd Resins

• Unsaturated Polyester

resins.

• Formaldehyde resins

• Amino Resins

• Epoxy Resins

A. Paint

• are stable mechanical mixtures of one or

more pigments.

• Pigments and extenders are carried or

suspended in dryings oils or solvents.

• solvent serves as the drying material to

which other ingredients might be added

Types of Paint

• Solvent based

• Water based

1. Emulsion based

2. Latex based

Manufacturing

Pigment Volume Concentration (PVC)

𝑃𝑉𝐶 =volume of pigment in paint

vol. of pigment in paint + vol. of nonvolatile vehicle constituents in paint

Table 1. Range of PVC for a given paint

Flat paints 50-75% Exterior house paints 28-36%

Semi-gloss

paints

35-45% Metal primers 25-40%

Gloss paints 25-35% Wood primers 35-40%

Sample Problem 1

It is desired to make an exterior house

paint of color blue with a reddish undertone.

The manufacturer decided to use a mass ratio

of 2:3, a combination of pigment to resin

(polyvinyl acetate, PVA). Solvent will then be

added to about 25% utilized PVA at a flow rate

of 100 kg/h. Determine if this combination will

qualify as an exterior house paint.The

following empirical data are available as

follows.

Sample Problem 1.0

Substance SG, @ 25 ℃

Ultramarine Blue 2.35

Phthalocyanine Blue 1.62

Prussian Blue 1.8

Polyvinyl Acetate 1.19

SolutionBasis: 1 hr operation

Identify:

Solvent—water (latex, PVA)

Pigment—Ultramarine Blue (reddish undertone property)

mH2O= 100.0 kg VH2O= 100.0 𝑘𝑔

1000𝑘𝑔

𝑚3

= 0.1 m3

Solve for Pigment and Resin mass and corresponding volume used:

mresin= 0.25(100)= 25.0 kg mpigment= 2

3× 25 = 16.667 𝑘𝑔

Vresin= 25.0 𝑘𝑔

1.19 (1000𝑘𝑔

𝑚3

= 0.02101 m3 Vpigment= 16.667 𝑘𝑔

2.35(1000𝑘𝑔

𝑚3

= 0.00709 m3

PVC= 0.00709

0.02101+0.00709+0.1× 100= 5.54%

B. Varnish

- refers to a preparation consisting of

resinous matter such as copal or lac,

dissolved in an oil or in alcohol or other

volatile liquid.

Examples

• Spirit Varnishes

• Oleoresinous Varnishes

• Japans

C. Lacquers

- defined as those non-convertible coatings

and principally as a coating composition

based on a synthetic, thermoplastic, film-

forming material dissolved in organic

solvents that dries by solvent evaporation

or a curing process that produces a hard,

durable finish.

D. Enamels

- It is used to get a good gloss because after

drying, the enamels will form a very good

lustrous and glossy finish.

Brushing

- This is the simplest method and also the

slowest and most expensive.

- Promotes better wetting of the surface and

can be used in restricted spaces, be useful

for small areas, with less wastage and

contamination of surroundings.

Roller

Air Spray

Airless Spray

Electrostatic Spraying

Autodeposition

Boysen’s KNOxOUT Technology

Anti Scratch/ Self Healing Paint

Microban Tech

Salamat sa Pagpaminaw