1. What is paint ?
Paint is the name of colored inorganic coating material applied on all whether natural or artificial equipment, vehicle, construction type products. The common name of the uncolored, transparent version of the same coating materials is varnish. Paint and varnish are used for two reasons:
– To increase the aesthetic look of applied materials
– To protect these items from corrosion
Whilst aesthetic look was very important, especially nowadays, protecting materials against corrosion for much longer time has become more important. The structural value and life of a materialdepends on anti-corrosive protection.
2. What is Corrosion?
Air, humidity, chemical vapor or physical, chemical friction, effects of various heat conditions cause wear and tear on the materials and it’s called corrosion. This wear and tear starts on the surface and finds its way into the material. In short, the material becomes unusable.
3. How to be protected from corrosion?
It is possible to protect the surfaces of materials for long periods by purposefully painting them with anticorrosive paints and lacquers. In short, it is necessary to disengage the materialfrom the corrosive factors in any environment. However, this is only possible by choosing the correct coating material and then applying it well. Choosing the correct coating product meeting the demand is not enough. The successful result of the application depends on the experience of the people applying the coating.
4. Choosing the Paint:
The most important factor whilst choosing the paint is to analyse the environment in which the material to be protected will be and then finding the product with proper durability.As a prerequisite, the choice must be made by people and/or companies who have the necessary experience on that subject for the painting system to be successful.
The application, which is as important as the paint itself, can be evaluated in two principles:
a) Surface Preparation:
The metal surfaces should be cleaned well. Grease should be removed first, then mechanical cleaning is performed by diskpaper or sandblasting. Afterwards primer is applied. Chemical cleaning is also very effective. However, sandblasting according to Swedish norms is the best surface cleaning method.
What is Surface Cleaning (Sandblasting) ?
The iron ore extracted from the soil is shaped as metal. Unprotected (uncoated) metal puts a tremendous effort to return to its original state (to return to soil). It rusts due to contact withwater and oxygen in either air or ambient environment. Thus, corrosion starts.
The factors which affect the metal before it is protected are as follows:
– Rust and cinder
– Dirt on the surface in form of salt, dust, grease and oil
– Surface profile
– Atmospheric conditions
Before paint is applied, the above factors should be eliminated and surface should be cleaned via sandblasting and the whole surface should be porous. The surface is prepared for the application of paint and other protective materials by sandblasting steel granule (grit) under high pressure.
The primitive way of surface cleaning is via sandpaper and silicic sand. To see international surface cleaning standards (ilgili sayfaya link -Yüzey Temizlik Dereceleri);
It is very important to apply primer and top coat in line with the required application conditions e.g. waiting period between primer and top coat. In some instances, depending on the necessity, a middle coat and mastic paint can be used.
1) Application with Air Spray:
Paint is sprayed via a paint gun using pressurized air. A very smooth film sheet in required thickness can be achieved. However, 30-40% of the paint will be lost. This loss will depend on the wind and the shape of the metal painted.
2) Application with Airless Spray: Only the paint material with a very high pressure from a small hole is sprayed. By this method, paint granules adhere to the metal surface in very small particles and a very thick film sheet is achieved. The application should be made by an experienced person, otherwise paint film thickness might change throughout the surface. On the other hand, the advantages of airless spray paint application are as follows:
• Since the paint has been sprayed with pressure, it adheres better to the surface. A thicker film sheet can be applied in one coat.
• Paints with high density, without need for thinning, can be easily applied with this method.
• There will be not be too much spillage of paint dust around.
• Consumption values decrease.
EPOXY PRIMER & EPOXY TOPCOAT USAGE MANUAL
1) Surface Application:
For the coating to perform expected function and protect the surface it was applied, it should adhere to that surface very well. Whatever type of resin that the material to be applied contains, the first and most important requirement of adherence is surface preparation. Therefore, application surface is carefully cleansed from dirt, oil and grease. Loose, old paint is removed. Rust and crust on the surface are removed via either sandblasting or sandpapering, whichever is suitable. After the surface cleaning is properly performed, application is made via brush, roll or spray. During the spray applications, proper mask should be worn. When application is made in small or closed areas, attention to proper ventilation is very important
2) Preparation of the Material:
The first and second (dryer) components of the epoxy material to be applied should first seperately and then together be mixed. If the mixing had not been properly made, resin and dryer will not be homogeneous and hardening will not be satisfactory. As a result, problems with regard to adherence, mechanical and chemical resistance will be observed.
Another requirement for a successful epoxy application is mixing the two components in the ratio advised by the producer company. For that end, every epoxy material’s dryer amount, produced by EKS, is predetermined and for every bucket of the material, a gallon dryer is matched.
First component of any EKS product should never be mixed with other companies’ second components. All epoxy primer, middle and top coats produced by EKS should be used with their own dryers and mismatches should be avoided.
3) Product Choice:
In cases where epoxy primer and topcoats produced by EKS are to be used, product to be used should be chosen taking the application surface and the conditions it will be exposed to into account. If necessary, you can contact with our company for consultancy.
4) Primer Application:
Primer should be used first in order to protect the surface, in the best possible way, prepared for coating. In order to protect the surface and provide better adherence between the surface and subsequently applied paint, usage of EKS brand epoxy primer is advised.For pot life and other technical information of the chosen primer, technical bulletin of the product should be read.
5) Increasing Film Thickness:
If the film thickness is requested to be increased, a middle coat is advised to be applied on top of the primer. EKOFILL 505 epoxy middle coat increases the resistance of the surface against external effects with its high filler and active pigment content. For pot life and other technical information of the product, technical bulletin of the product should be read.
6) Topcoat Painting:
After cleaning and primer application, surface is painted with a EKS brand topcoat epoxy paint to provide required color, gloss and drying and surface coating is completed. For pot life and other technical information of the product, technical bulletin of the product should be read.
7) Hardening Requirements:
The reaction between the epoxy resin and the hardener continues depending on the ambient temperature and humidity. Therefore, application in highly humid weather and below 5°C ambient temperature should be avoided. The application surface temperature is also very important.
8) Waiting Period between coats:
The waiting period between coats depends on the weather conditions and it’s very important. If the waiting period between coats is more than a few days, problems regarding adherence might be observed. If the waiting period between the coats is more than 48 hours, surface should be sandpapered and roughened to increase adherence of the new coat unto the prior one.
If the second coat epoxy is applied within 24-48 hours (at 20-25°C) after the first coat on the surface, a chemical bonding between the two coats will be realised since the chemical hardening of the first coat was completed. If additional coating will be applied, the same is true for the other coats and although there will be a few coats, a single layer will form. This feature of the epoxy systems will provide them much higher durability compared to other systems.
9) Drying Period:
Chemical reaction will continue for a week in epoxy systems. Therefore, a surface or floor on which epoxy was applied should be expected to perform against the required chemical and/or mechanical conditions earliest after one week of application.
NOTE : The information provided here is for epoxy systems. In general, situation will not change too much in two-component systems. Above conditions cover other two component systems, too. Polyurethane, acrylic and other two-component paintsare also used under similar conditions.