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Epoxy : Durability of Electrostatic Powder Coat vs. Sprayed solvent base.

Epoxy Coating - electrostaic vs. sprayed solvent base epoxy...

We are coating zinc die cast buckles. Our customer requires and epoxy coating. What differences can we expect based on the method of application. Powder coating (electrostatically applied) vs. Spraying solvent based epoxy. What is the difference in durability/abrasion resistance? What is the difference in surface finish?

HOWARD REITER
Rome Fastener Corp - Milford, Connecticut USA
2000

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The cured films are chemically pretty much the same, the solvent based spray will generally have less "orange peel" effect, and will be harder. Powder has a real environmental benefit (no solvent emissions), and is easier to use and clean up, but no other real advantages.

Jeff Watson
- Pearland, Texas
2000

My experience comparing powder paints and liquid paint of equal quality has been as follows:

Normally powder paint will form a harder more durable coating as to it's impact and abrasion resistance.

Life cycle of an epoxy coating would be the same for liquid and or powder.

The surface finish of powder and liquids will be nearly equal if both are formulated for your requirements and both are of equal film build.

If the coated buckles are used in an exterior application the UV resistance of epoxy is normally poor and either the liquid or powder will tend to chalk or dull in a few months.

Application issues that are associated with each are:

Powder paint does not have many of the environmental issues that are associated with solvent, or liquid coatings. There is no solvent to be released to the atmosphere. In some states that are incentives for companies to change from liquid to powder.

You can get a very good air dry solvent based coating and not require baking. All powder paint materials must be baked.

You can spray powder paint and reclaim the over spray, liquid paint over spray is waste.

You can powder paint in a booth that the plant air is returned to the room. Liquid spray normally requires discharge to the building exterior, unless you can use a Sorbent type booth system.

Hope this helped.

Ty Caley

Tyrone L. Caley
Caley & Associates - Jefferson City, Missouri

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Hi there, I am trying to decide whether to buy an outdoor lighting fixture and my choices are between a baked enamel finish, or a powder coated finish. Can you make any suggestions with a reason behind it for me.

Thanks,

Joshua Smith
Josh Smith Studios - Williams Bay, WI, United States
2005