Khalid Shamlawi is the Specifications Manager for Jotun Powder Coatings and looks after UAE region as well as Oman, Kuwait, Bahrain, and Egypt. Among his duties is to establish and maintain strong relationships with key upstream clients and project owners to influence specification decision-making at the project management cycle. He’s a keynote speaker for all events in the region with expertise in Powder Coating.
Jotun has been developing paints since 1926 and is now one of the world’s largest paint companies. Today, the group comprises of 67 companies and 40 production facilities across the world and employs more than 10.200 dedicated employees.
Which type of paint you consider better, powder coating or PVDF?
They are both good options, no question on that. For me, it is powder due to the following reasons.
- VOC contents are negligible for powder, while it is moderate to high for PVDF.
- You can achieve the required result with powder with a single coat, while you will need up to 3 to 4-coats for PVDF.
- Colour consistency is easier to control with powder, with PVDF is much harder to control.
- Easier process for the user. There are a much larger large number of approved applicators for powder coating.
- Guarantee comes at 25-30 years for all colours of powder, for PVDF is quite vague as it depends a lot on specifications.
- There is a richer finish on powder.
What about anodization?
Anodization used to be dominant in our industry but these days belong to the past as its share constantly declines. Main reason is the inconsistency of colour, it is very difficult to control. This is due to variance of metal constituents, temper, anodizing tank chemistry, shape geometry and material load size.
As the world becomes more environmentally conscious, we are moving towards healthier practices. Anodizing has low friendliness, there are concentrated acid baths (vapour concerns) and waste disposal concerns.
Further reasons that anodizing market shares continues to decline is the very limited colour and finish choices and the high resource consumption.
What is the optimum paint thickness for powder coating?
We measure dry film thickness as per Qualicoat standards.
In the final assessment, none of the measured values shall be less than 80% of the specified minimum value otherwise the thickness test as a whole will be considered unsatisfactory.
The results shall be assessed as shown by four typical examples (minimum thickness for coatings of 60 μm):
- Example 1:
Measured values in μm : 82, 68, 75, 93, 86 average: 81
Rating: This sample is satisfactory.
- Example 2:
Measured values in μm : 75, 68, 63, 66, 56 average: 66
Rating: This sample is good because the average thickness is more than 60 μm and because no value measured is less than 48 μm (80% of 60 μm).
- Example 3:
Measured values in μm : 57, 60, 59, 62, 53 average: 58
Rating: This sample is unsatisfactory and comes under the heading “rejected samples.
- Example 4:
Measured values in μm : 85, 67, 71, 64, 44 average: 66
Rating: This sample is unsatisfactory although the average thickness is more than 60 μm. The inspection is unsatisfactory because the measured value of 44 μm is below the tolerance limit of 80% (48 μm).
Across different markets and climates, the choices of material for windows varies. In Northern Europe PVC is dominant, while as we move to Mediterranean countries and Middle East, aluminium takes over.
There is no question, aluminium is a far better material than uPVC. I can sum up advantages as below.
Much more durable. An aluminium window has lifecycle of more than 60 years while uPVC is approximately 25-40 years.
Maintenance. Aluminium does not crack, peel or rot and there is ease to change a broken glass by removing the glazing beads. uPVC on the contrary is a very soft material that can easily get scratched while you have to exchange the whole vent frame if glass is glued in for stability.
Aluminium has high stability due to great strength to weight ratio and high wind as well as burglary resistance. uPVC needs steel or aluminium reinforcement steel to reach the same stability in same sizes.
There is great colour variety in aluminium through powder, liquid or anodizing. On the other hand, there are only limited shades of whites, greys and browns and not all uPVC is UV resistant which leads to colour fading.
There is lot of discussion lately for fire safety and regulation. This debate is global since there are several incidents with fires in building. Does paint contribute to fire performance and how much?
We need to be able to interpret the fire classification test results. The latest Dubai Civil Defense Regulation has adopted European Standard EN 13501-1. A typical classification comes as e.g. B – s1- do. Let’s see what this means.
- First digit is the reaction to fire classification which determines how much (if any) a building material contributes to the spread of fire.
Class A1 – A2 = non-combustible materials.
Class B, C, D = ranges from very limited to medium contribution to fire.
Class E, F = high contribution to fire.
- The “s” part relates to the total smoke propagation, during the first 10 minutes of exposure. These determine a “smoke” index:
s1 = little or no smoke.
s2 = quite a lot of smoke
s3 = substantial smoke.
- The “d” part relates to the flaming droplets and particles, during the first 10 minutes of exposure.
d0 = none.
d1 = some.
d2 = quite a lot.
According to EN 13501-1, Jotun Super Durable paint fall under A2-s1,d0 category, while Jotun Durasol is plain A1.