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1.0 INTRODUCTION OF PAINT

Figure 1.0: Dried green paint

Paint is any liquid, liquifiable, or mastic composition which after application to a

substrate in a thin layer is converted to an opaque solid film.

Paint also may be described as a liquid composition capable of being applied over a

surface. The viscosity of this liquid composition is adjusted to ease application by airless

spray, brush, roller, etc. During the curing or drying process, this film becomes an

impermeable, strongly protective, decorative coating. Modern paints have evolved due

to an increasing demand for higher performance coatings. These paints have highly

complicated compositions including four main components: the binder, the pigment, the

extender, and the solvent.

1.1 FUNCTIONS OF PAINT

Paint is a fluid that dries to form a continuous solid film when spread over a

surface or substrate. Depending on its type and properties, paint can perform

one or more of the following functions:

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Table 1.1: Functions of Paint

1.2 PAINT SYSTEMS AND COMPONENTS

A paint system is basically composed of primer/sealer, undercoat and topcoat as

shown in Figure 1.1.

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Depending on the design requirement, texture coating may be provided. Due to

volume constraint, this guide book will focus on paints that are commonly used in

the local market. The functions of each system component are illustrated in Table

1.2 below.

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1.3 CLASSIFICATION OF PAINT

With technological advancements, the traditional classification of paints into

either enamel or emulsion has become misleading. Today, the industry has

enamel paints that can be diluted with water and emulsion paints that have

smooth, glossy finishes. Hence, it becomes essential to identify paint by its resin

components to minimize confusion.

Appendix A shows some examples of paints classified by their resin components

and properties. In general, ―enamel‖ refers to solvent-based Alkyd resin which is

generally used for wood and metal surfaces. Apart from classifying paints by their

resin components, paints may also be classified in accordance with their curing

mechanism, solvent used, function and market segment as shown in Table 1.3

Table 1.3: Classification of Paint

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1.4 PROPERTIES OF PAINT

The properties of paint determine the general quality of the coating and its

workability, ease of application and resistance characteristics. Table 1.4 shows

some basic properties of paints.

Table 1.4: Essential Properties of Paint

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2.0 COMPONENTS OF PAINT

There are four main components: the binder, the pigment, the extender, and the

solvent. 

2.1 Binders

Binders are the film-forming components of the paint in which the pigment and

extenders are distributed. In most cases, binders produce the greatest volume of

paint film and have the greatest influence on the paint characteristics

(drying/curing, adhesion, hardness, strength, resistance to chemicals, etc.).

Therefore, the type of binder is generally used to describe the generic type of

paint.

The binder, commonly referred to as the vehicle, is the actual film forming

component of paint. It is the only component that must be present; other

components listed below are included optionally, depending on the desired

properties of the cured film.

The binder imparts adhesion , binds the pigments together, and strongly

influences such properties as gloss potential, exterior durability, flexibility, and

toughness. Binders include synthetic or natural resins such as acrylics,

polyurethanes, polyesters, melamine resins, epoxy and oil. Binders can be

categorized according to drying, or curing mechanism. The four most common

are simple solvent evaporation, oxidative crosslinking , catalyzed polymerization, 

and coalescence. There are others.

Note that drying and curing are two different processes. Drying generally refers

to evaporation of the solvent or thinner, whereas curing refers to polymerization

of the binder. (The term "vehicle" is industrial jargon which is used inconsistently,

sometimes to refer to the solvent and sometimes to refer to the binder.)

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Depending on chemistry and composition, any particular paint may undergo

either, or both processes. Thus, there are paints that dry only, those that dry then

cure, and those that do not depend on drying for curing.

Paints that dry by simple solvent evaporation contain a solid binder dissolved in a

solvent; this forms a solid film when the solvent evaporates, and the film can re-

dissolve in the solvent again. Classic nitrocellulose  lacquers fall into this

category, as do non-grain raising stains composed of dyes dissolved in solvent.

Latex paint is a water-borne dispersion of sub-micrometre polymer particles. The

term "latex" in the context of paint simply means an aqueous dispersion; latex

rubber (the sap of the rubber tree that has historically been called latex) is not an

ingredient.

These dispersions are prepared by emulsion polymerization. Latex  paints cure by

a process called coalescence where first the water, and then the trace, or

coalescing, solvent, evaporate and draw together and soften the latex binder

particles and fuse them together into irreversibly bound networked structures, so

that the paint will not redissolve in the solvent/water that originally carried it.

Residual surfactants in the paint as well as hydrolytic  effects with some polymerscause the paint to remain susceptible to softening and, over time, degradation by

water.

Paints that cure by oxidative crosslinking are generally single package coatings

that when applied, the exposure to oxygen  in the air starts a process that

crosslinks and polymerizes the binder component. Classic alkyd  enamels would

fall into this category.

Paints that cure by catalyzed polymerization are generally two package coatings

that polymerize by way of a chemical reaction initiated by mixing resin and

hardener, and which cure by forming a hard plastic structure. Depending on

composition they may need to dry first, by evaporation of solvent. Classic two

package epoxies or polyurethanes would fall into this category.

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Still other films are formed by cooling of the binder. For

example, encaustic or wax  paints are liquid when warm, and harden upon

cooling. In many cases, they will resoften or liquify if reheated.

Recent environmental requirements restrict the use of Volatile Organic

Compounds (VOCs), and alternative means of curing have been developed,

particularly for industrial purposes. In UV curing paints, the solvent is evaporated

first, and hardening is then initiated by ultraviolet light. In powder coatings there

is little or no solvent, and flow and cure are produced by heating of the substrate

after application of the dry powder. 

2.2 Pigment 

Pigments are the small particles of solid material distributed in the paint.

Pigments can be divided into two groups: anticorrosive pigments, which prevent

corrosion of metals by chemical and electo-chemical means, and coloring

pigments, which give permanent color and hiding capacity.

Pigments are granular solids incorporated into the paint to contribute color,

toughness, texture or simply to reduce the cost of the paint. Alternatively, some

paints contain dyes instead of or in combination with pigments.

Pigments can be classified as either natural or synthetic types. Natural pigments

include various clays, calcium carbonate, mica, silicas, and talcs. Synthetics

would include engineered molecules, calcined clays, precipitated calcium

carbonate, and synthetic silicas. 

Hiding pigments, in making paint opaque, also protect the substrate from the

harmful effects of ultraviolet light. Hiding pigments include titanium

dioxide, phthalo blue, red iron oxide, and many others.

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Fillers are a special type of pigment that serves to thicken the film, support its

structure and simply increase the volume of the paint. Fillers are usually

comprised of cheap and inert materials, such as diatomaceous

earth, talc, lime, baryte, clay, etc. Floor paints that will be subjected to abrasion

may even contain fine quartz sand as filler. Not all paints include fillers. On the

other hand some paints contain very large proportions of pigment/filler and

binder.

Some pigments are toxic, such as the lead pigments that are used in lead paint. 

Paint manufacturers began replacing white lead pigments with the less toxic

substitute, titanium white (titanium dioxide), even before lead was functionally

banned in paint for residential use in 1978 by the U.S. Consumer Product SafetyCommission. The titanium dioxide used in most paints today is often coated with

silicon or aluminum oxides for various reasons such as better exterior durability,

or better hiding performance (opacity) via better efficiency promoted by more

optimal spacing within the paint film. 

2.3 Extenders

Extenders are natural or synthetic materials finely distributed in the paint. Theycan also be considered inert pigments. The particles have different sizes and

shapes: nodular, lamellar, acicular, etc. Extenders have significant influence on

the physical properties of the paint. These include the gloss, water & chemical

resistance, mechanical strength and hardness, and film build of the paint. 

2.4 Solvent

Solvents are used principally to facilitate application. Active solvents dissolve thebinder to make a solution suitable for various methods of application. Latent

solvents make the coating easier to apply, control the evaporation rate, and

improve the quality of the final film. Diluent solvents are used in limited quantities

in conjunction with active solvents to reduce costs. Diluent solvents do not

dissolve the binder.

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The main purposes of the solvent are to adjust the curing properties

and viscosity  of the paint. It is volatile and does not become part of the paint film.

It also controls flow and application properties, and affects the stability of the

paint while in liquid state. Its main function is as the carrier for the non volatile

components. In order to spread heavier oils (i.e. linseed) as in oil-based interior

housepaint, a thinner oil is required. These volatile substances impart their

properties temporarily—once the solvent has evaporated or disintegrated, the

remaining paint is fixed to the surface.

This component is optional: some paints have no diluent. Water  is the main

diluent for water-borne paints.

Solvent-borne, also called oil-based, paints can have various combinations of

solvents as the diluent, including aliphatics, aromatics, alocohols, ketones and

white spirit. These include organic solvents such as petroleum distillate, ester,

glycol ethers, and the like. Sometimes volatile low-molecular weight synthetic

resins also serve as diluents. Such solvents are used when water resistance,

grease resistance, or similar properties are desired. 

2.5 Additives 

Besides the four main categories of ingredients, paint can have a wide variety of

miscellaneous additives, which are usually added in very small amounts and yet

give a very significant effect on the product. Some examples include additives to

modify surface tension, improve flow properties, improve the finished

appearance, increase wet edge, improve pigment stability,

impart antifreeze  properties, control foaming, control skinning, etc. Other types of

additives include catalysts, thickeners, stabilizers, emulsifiers , texturizers,

adhesion promoters, UV stabilizers, flatteners (de-glossing agents), biocides to

fight bacterial growth, and the like.

Additives normally do not alter the percentages of individual components in a

formulation. 

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3.0 TYPES OF PAINTS 

Paints can be classified by generic types of binders, by function, or by drying/curing

mechanism. 

3.1 Antifouling coatings

Antifouling coatings are chosen for their ability to control marine growth and

limit undue hull roughness. The effect of roughness is an increase in the

resistance to movement, resulting in reduced speed and increased fuel

consumption. The main cause of hull roughness is fouling (growth of marine

plants and animals on the hull). Modern antifoulings fall into three main groups:

soluble matrix, insoluble matrix and self-polishing. 

  Soluble matrix antifoulings have a natural rosin binder that slowly

dissolves in seawater. When the coating is immersed in seawater, the

biocide leaches out of the paint, but the release rate soon drops below

that required to control fouling. As a result, effective protection lasts for a

short time (12 months).

  Insoluble matrix antifoulings have a binder that is insoluble in seawater.

Since only biocides are released, the paint film is left as a porousskeleton. As the porous layer increases, the rate of biocide release

decreases. Eventually no more biocides can be released and performance

drops dramatically. Effective life of this type of antifouling is 24 months.

  Self-polishing antifoulings are based on acrylic binders and fall into two

categories: tin-free and tin-bearing. In contact with seawater, the binder

hydrolyses or ablates and dissolves at an even, predictable rate. As the

antifouling wears away or ―polishes,‖ new biocide is continually exposed

down to the last few microns of antifouling. The benefits provided by a

self-polishing antifouling are increased service life (up to 60 months) and avery effective protection against fouling. The effective life span is directly

proportional to the applied film thickness. 

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3.2 Acrylic coatings

Acrylic coatings are derived from an extensive family of polymers. Acrylics are

single component paints that dry through solvent evaporation. They are not

dependent on temperature and offer good adhesion to similar generic types such

as vinyl. Designed for use on a wide variety of substrates, acrylics display

excellent gloss and color retention. They are often used to modify other generic

types to improve water and chemical resistance, flexibility, UV stability, gloss and

color retention. 

3.3 Alkyd coatings

Alkyd coatings are a combination of natural oils and other chemicals. Alkyds are

single component paints cured by oxidation. They are good general purpose

coatings designed for a variety of applications above water. Alkyds are easy to

apply and can be used for primers or topcoats. They offer good color and gloss

retention, but only fair-to-poor chemical resistance. Alkyds are not suitable for

application over alkaline surfaces.

3.4 Epoxy coatings

Epoxy coatings are synthetic resins designed to provide a predetermined

polymer structure. Epoxies are two-component, chemically cured paints. Since

epoxies are synthetic, they are developed and used for a great variety of

purposes. They form hard, abrasion-resistant films with excellent water,

chemical, alkali and solvent resistance and are used on a variety of substrates

from general purpose primers to high performance tank linings. Some epoxies

present difficulties in overcoating due to hardness of cured film. Epoxies have atendency to chalk and fade in direct sunlight. Epoxies are often modified with

other binders to improve properties such as cathodic protection, surface

tolerance, wetting, chemical resistance, gloss and color retention, abrasion

resistance, and flexibility. 

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3.5 Heat resistant silicone coatings

Heat resistant silicone coatings are self-polymerizing resins. They are cured by

heat. Silicones offer excellent high heat resistance and good weather resistance.

They are less prone to oxidation, giving excellent resistance to UV and

weathering. Solvent resistance is marginal but improves markedly after exposure

to very high temperatures and the burn-off of organic materials. The expense of

silicone limits its application, but it is often used to modify other generic types in

order to increase heat resistance. 

3.6 Polyurethane coatings

Polyurethane coatings are formed by a reaction between hydroxy and isocyanate

compounds. They are the newest and potentially the largest polymer family in the

coatings industry. Polyurethanes are normally two-component, chemically cured

paints, but are also available in single-component form. Available in a wide range

of formulations, polyurethanes are tough and abrasion-resistant, provide

excellent chemical and solvent resistance, weathering properties, and gloss

retention. They withstand mild acids and alkali and work well in combination with

epoxy primers. Two-component formulations are sensitive to moisture in the wetstage, but when fully cured have an outstanding resistance to humidity. Single

component formulations react with humidity to produce a dense, chemical- and

corrosion-resistant film. Polyurethanes are often considered to be the best all-

around coatings currently produced. 

3.7 Vinyl coatings

Vinyl coatings are film-forming polymers consisting of varying ratios of polyvinylchloride, polyvinyl acetate and polyvinyl alcohol. Vinyls are single-component

paints that dry through solvent evaporation. They provide excellent acid and

alkali resistance. Vinyls require a high degree of surface preparation and offer

limited resistance to oil and solvents. Low solids content and high V.O.C. are

making this product obsolete in the United States. 

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3.8 Zinc silicate coatings

Zinc silicate coatings are inorganic coatings with high metallic zinc content for

cathodic protection. Zinc silicates are two-component products chemically cured

through water absorption. They may be solvent or water borne and require a high

degree of surface preparation to work properly (intimate contact with steel is

necessary). Zinc silicates are extremely resistant to mechanical stress, heat and

organic solvents. Zinc silicates should not be used in acidic environments without

being top-coated. Because combinations of zinc and rainwater are alkaline, zinc

silicates should not be used in conjunction with alkyds. Zinc silicates are often

designed as shop primers. 

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4.0 SURFACE PREPARATION 

Good surface preparation is the most important part of any coating job. The greatest

percentage of coating failures can be directly linked to poor surface preparation. A paint

system applied to an unsuitable surface will not have a secure foundation to resist

abrasion and other mechanical stress to which it may be subjected. Surface

contaminants such as grease, oil, dirt or salt will prevent contact between the new

coating and steel or existing coatings, leading to poor adhesion and eventual stripping

and peeling.

Rust and scale are other contaminants that prevent contact between the new coating

and the steel substrate. They will allow pockets of moist air to remain which form

corrosion cells beneath the new paint film and quickly destroy it. Salts in rust or on the

steel substrate may encourage blistering by osmosis. Therefore, all surface

contaminants must be removed. The methods of removal include fresh water, removal

with the use of power tools and grit blasting. 

4.1 Solvent cleaning

Solvent cleaning is a process utilizing solvents or other cleaning compounds to

remove oil, grease and other contaminants. Since solvents can be inherently

detrimental to subsequent coatings, it is extremely important to remove any

solvents or cleaning compounds from the surface prior to further preparation or

applications. Solvent cleaning is often considered to be a preliminary step in the

total surface preparation procedure. 

4.2 Hand or power tool cleaning

Hand or power tool cleaning is often considered technically suitable as a means

of cleaning surfaces for coatings application; however, this method is laborious

and frequently achieves less than satisfactory results. The methods of hand and

power tool cleaning include hand brushing, scraping, mechanical wire brushing,

disc grinding, chisel hammering and needle gunning. The inherent danger with

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this method is the possibility of polishing and/or chipping the surface. Using a

variety of hand and power tools to prepare a surface likely gives the best results.

This method is best suited for areas in which grit blasting is not possible or

practical; however, it should be limited to small jobs and areas with difficult

access. 

4.3 Abrasive blast cleaning

Abrasive blast cleaning is the most effective and efficient method of removing

rust, mill scale, paint, and other contaminants from a substrate. The high velocity

impact of abrasive particles against the substrate cuts or abrades the impurities

and removes them from the surface. Abrasive blast cleaning generally provides

the proper surface profile to ensure adhesion of the coating system. When the

proper type and size of grit, air pressure, and nozzle are chosen, abrasive

blasting is the fastest and most effective method of surface preparation.

Unfortunately, it is also one of the most expensive methods of surface

preparations and is presenting increased environmental concerns throughout the

world. 

4.4 Water jetting

Water jetting, also known as hydroblasting, uses a high energy water stream

(5,000 to 50,000 PSI) to strip rust, scale and paint. It is also a very effective

means of removing water-soluble salts, grease and oil. The advantages of water

 jetting include controlled removal of individual layers of paint, effective removal of

soluble salts, a lack of dust and spark hazards, and a lack of contamination to

surrounding areas. Disadvantages include the inability to create a surface profile,

decreased production rates, and expense. Written and visual standards for water

  jetting have recently been introduced to the industry, and this method is

becoming an increasingly popular method of surface preparation throughout the

world.

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4.5 Electrolytic descaling

Electrolytic descaling is a method of surface preparation recommended where

age and neglect make normal paint maintenance impossible. Anodes, specially

designed to achieve heavy electrical current flow, are supplied as magnesium

alloy strips. Strips are clamped or welded to steel at specified intervals and a

tank is filled with clean seawater. A very strong electrical current is produced in

the tank, which causes a breakdown of oxides (scale and rust) and the formation

of a soft calcareous layer on the surface of the steel. The formation of this layer

then forces the rust or scale to loosen and fall off. The tank is emptied, washed

down, dried, and is ready for coating. Electrolytic descaling offers performance

economy over traditional methods of surface preparation. 

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5.0 APPLICATIONS

Paint can be applied as a solid, a gaseous suspension (aerosol) or a liquid and also for

coating. Techniques vary depending on the practical or artistic results desired.  

5.1 Coating 

There are a variety of methods used to apply coatings, ranging from dipping to

electrostatic spray. Because of size, time and cost constraints of a project, many

applications are not suitable or practical in given conditions. The most popular

and practical methods of application are brush, roller, and conventional and

airless spray. Note that paint application should only be carried out when

prevailing climatic conditions are suitable.

Brush application is the historical method of application and is quite efficient in

coating small and/or complex pieces. Application by brush is extremely effective

at working paint into rough and porous substrates and is ideal for priming pitted

surfaces and stripe-coating edges, flanges, and corners. Choosing the proper

size, length, shape and bristle is extremely important when utilizing brush

application. The disadvantages of brush application include its impracticality for

use on large areas, its difficulty in controlling film build, and its impracticality for

use with fast-drying materials.

Roller application is two to three times faster than brush application and is ideal

for large, flat surfaces. Roller cores may be wire mesh, plastic or phenolic; covers

may be polyester, mohair, lambskin or nylon. Choice of roller type is dependent

on the type of paint being applied and the surface being coated. Application by

roller proves difficult to use in complex areas and in controlling film build. Rollerapplication should not be used when priming.

Conventional spray  application is a widely accepted and speedy method of

painting large surfaces. The coating material is atomized by a stream of

compressed air and is propelled to the substrate by the air pressure.

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Air and fluid pressures can be controlled to produce a proper fan pattern for

application. Various nozzle sizes accommodate different paint types. It is very

important to use the proper air pressure, usually 40 - 80 PSI. Disadvantages of

conventional spray include the high loss of product caused by over spray,

billowing and turbulence caused by required compressed air, and the sometimes

necessary thinning of coatings to achieve proper atomization.

Airless spray  application is the most effective method of coatings application.

Coatings material is pressed towards the nozzle or tip of a gun at high pressure.

The coating is diffused by being forced through a small opening where the drastic

change in pressure atomizes the paint and propels it to the substrate at a

powerful rate. Application by airless spray increases production rate, reducesover spray, allows heavier film build, and eliminates the need for a pressure pot.

Disadvantages of airless spray include difficulty in coating small, intricate objects,

a fixed spray tip, and little control over the quantity of coatings being applied.

5.2 Solid 

As a solid (usually used in industrial and automotive applications), the paint is

applied as a very fine powder, and then baked at high temperature. This meltsthe powder and causes it to adhere (stick) to the surface. The reasons for doing

this involve the chemistries of the paint, the surface itself, and perhaps even the

chemistry of the substrate (the overall object being painted). This is commonly

referred to as "powder coating" an object.

5.3 Gas 

As a gas or as a gaseous suspension, the paint is suspended in solid or liquid

form in a gas that is sprayed on  an object. The paint sticks to the object. This is

commonly referred to as "spray painting" an object. The reasons for doing this

include:

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The application mechanism is air and thus no solid object ever touches

the object being painted;

The distribution of the paint is very uniform so there are no sharp lines;

It is possible to deliver very small amounts of paint;

A chemical (typically a solvent ) can be sprayed along with the paint to

dissolve together both the delivered paint and the chemicals on the

surface of the object being painted;

Some chemical reactions in paint involve the orientation of the

paint molecules . 

5.4 Liquid 

In the liquid application, paint can be applied by direct application

using brushes, paint rollers, blades, other instruments, or body parts such as

fingers.

Paint application by spray is the most popular method in industry. In this, paint is

atomized by the force of compressed air or by the action of high pressure

compression of the paint itself, which results in the paint being turned into small

droplets which travel to the article which is to be painted.

Rollers generally have a handle that allows for different lengths of poles which

can be attached to allow for painting at different heights. Generally, roller

application takes two coats for even color. A roller with a thicker nap  is used to

apply paint on uneven surfaces. Edges are often finished with an angled brush.

After liquid paint is applied, there is an interval during which it can be blended

with additional painted regions (at the "wet edge") called "open time." The open

time of an oil or alkyd-based emulsion paint can be extended by adding white 

spirit , similar glycols such as Dowanol (propylene glycol ether) or commercial

open time prolongers. This can also facilitate the mixing of different wet paint

layers for aesthetic effect. Latex and acrylic emulsions require the use of drying

retardants suitable for water-based coatings.

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Paint may also be applied by flipping the paint, dripping, or by dipping an object

in paint. Interior/exterior house paint tends to separate when stored, the heavier

components settling to the bottom. It should be mixed before use, with a flat

wooden stick or a paint mixing accessory; pouring it back and forth between two

containers is also an effective manual mixing method. Paint stores have

machines for mixing the paint by shaking it vigorously in the can for a few

minutes. The opacity and the film thickness of paint may be measured using

a drawdown card . 

Oil-based paints when dry tend to be very durable, washable, and long-lasting.

The paint would take about almost 1 day to dry. Water-based paints tend to be

the safest and easiest to clean up after using—the brushes and rollers can becleaned with soap and water.

It is difficult to reseal the paint container and store the paint well for a long period

of time. It should be stored upside down, for a good seal. Storage should be in a

cool dry place, protected from freezing.

Proper disposal of left over paint is a challenge. Sometimes it can be recycled:

Old paint may be usable for a primer coat or an intermediate coat, and paints ofsimilar chemistry can be mixed to make a larger amount of a uniform color.

If it is necessary to dispose of paint, one approach is to dry it, either by leaving

the lid off until it solidifies (which tends to work well only for small quantities), or

by pouring it into a disposable drying device, such as a piece of plywood

surrounded by a lip. Once dry, the paint may be discarded with normal trash. Wet

oil based paint should be treated as hazardous waste, and disposed of according

to local regulations. 

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6.0 BENEFITS OF PAINT

6.1 Life Cycle

Researchers have calculated that one ton of steel is completely converted intorust every 90 seconds. Since today’s modern economic infrastructures are built

with steel, this ceaseless action of rust and corrosion takes a healthy toll on

national wealth as well as on the profitability of industrial companies. The cost of

corrosion in developed countries is estimated to equal 3% to 4% of their gross

national product. Up to 25% of this huge loss can be prevented using available

technologies to slow or stop corrosion.

Prevention of corrosion is a minor part of the total cost of any construction.

Professional application of modern high-quality coatings is a reliable and cost-

effective method for prolonging service life and is normally a very minor

expenditure compared to the value of the total investment.

A coating system is designed based on the area to be protected and the service

conditions to which it is exposed. The areas vary from underwater hulls to

superstructures, from ballast tanks to above ground storage tanks, and from

bridges to industrial plants. The design of a coating system must take into

account all these variables. In addition, the surface preparation and application

methods can become determining factors in choosing one coatings system over

another.

All paints will eventually age and gradually lose their protective properties. When

premature breakdown occurs, the first reaction is usually condemnation of the

paint, but this is seldom justified. Most premature failures can be avoided ifsound specifications are prepared and adhered to in all respects. At least 80% to

90% of coatings failures are a result of poor or inadequate surface preparation,

application technique, and application under poor or unsuitable conditions,

insufficient thickness or the use of unsuitable paint types. 

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6.2 Maintenance

The need to perform maintenance can be measured against the internationally

accepted ISO 4628 - Evaluation of Degrading of Paint Coatings. This is a

pictorial standard giving objective criteria for evaluating coatings breakdown by

rust, blistering, cracking, flaking and chalking. International experience shows the

most cost-effective maintenance interval to be when a degree of 1% rust area is

reached. Allowing rusting and coating breakdown to continue becomes very

costly to repair, while prompt and immediate touch-up is inexpensive and highly

effective.

Even top-quality coatings systems will require maintenance at some point. A

protective coatings system must be maintained in order to achieve the desired

performance life of a structure. Much like an engine, preventive maintenance of a

coatings system will allow it to perform in the desired manner and help prevent

the spread of corrosion should a breakdown occur. The benefits of a properly

maintained coatings system are long term cost savings and reduction of rework.

Maintenance is necessary both for protection and for appearance.

6.3 Health and Safety

These notes are designed to give general information regarding health and

safety issues when using paint and thinners.

6.3.1 Personal Protective Equipment: 

When using paints and thinners, it is extremely important to wear

protective clothing and safety glasses. The use of an appropriate, properly

fitted, NIOSH/MSHA approved respirator is recommended. For confined

space applications, consult with your on site health and safety department

for specific recommendations.

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6.3.2 Fire and Explosion Dangers: 

The majority of paints contain flammable organic solvents. To avoid the

possibility of fire or explosion, all sources of spark or flame should be kept

well away from any area where paint is stored or in use.

6.3.3 Inhalation Dangers: 

The inhalation of dust, fumes and paint vapors should be avoided. The

best means of protection is a respirator. Consult your safety and health

department for specific recommendations on the type of respirator best

suited to your job.

6.3.4 Skin and Eye Contact: 

Various constituents in paint can cause skin and eye irritation. Proper

precautions should be taken to avoid direct contact with liquid paint. The

following general precautions should be followed:

Wear sensible clothing that covers as much of the body as

possible.

If clothing becomes soaked with paint, remove clothing wash with

soap and water. Launder clothing before reuse.

Always wear gloves.

Do not touch mouth or eyes with gloves.

If eyes are splashed with paint, rinse them immediately with water

for at least 15 minutes.

If skin is splashed with paint, wash immediately with soap and

water. Do not use solvent to clean skin.

Read and follow additional precautionary statements on the label

and/or MSDS.

6.3.5 Disposal: 

The disposal of waste and empty containers should follow all local and

national regulations regarding such materials. 

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6.4 Precaution from dangers 

Non-toxic paints – Average household paint contains up to 10,000 chemicals, of

which about approximately 300 are toxins, and 150 are harmful and have been

linked to kidney damage, liver damage, or cancer . Even after application and

drying, paints and finishes continue to release these toxic emissions into the air

for many years to come. The sources of those toxins are VOCs. Up until recently

very high levels of VOC's were widely utilized in paint products and finishes. Non-

Toxic paints do not contain as many volatile organic compounds, which makes

enclosed air safer to breath for people vs. regular paint. It also has a less

damaging effect on the environment as it reduces landfill, groundwater and

ozone depleting contaminants. VOC's are the second largest source of emissionsinto the atmosphere after automobiles . 

7.0 REFERENCES

o Bently, J. (Author) and Turner, G.P.A. (Author) (1997). Introduction to 

Paint Chemistry and Principles of Paint Technology . Unk.. ISBN

0412723204. 

o Talbert, Rodger (2007). Paint Technology Handbook . Grand Rapids,

Michigan, USA. ISBN 1574447033. 

o Woodbridge, Paul R. (Editor) (1991). Principles of Paint Formulation .

Unk.. ISBN 0412029510. 

o http//:www.google.com

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FACULTY OF APPLIED SCIENCE

BACHELOR OF SCIENCE (Hons)

APPLIED CHEMISTRY (AS225)

COLLOID AND SURFACE CHEMISTRY

(CMT 602)

ASSIGNMENT:

APPLICATION OF PAINT

PREPARED BY:

AHMAD YAAKOB TASYRIF B MD ADNANI

(2008410992)

PREPARED FOR:

MR. STEPHEN LEE KOON LIANG

DATE SUBMITTED:

16 OCTOBER 2009