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Ask the Expert Question-and-Answer Archive by Ron Joseph April, 2005 Paints Designed for Electrostatic Application Q. I need to get info, on what paints are available and VOC compliant with the state, for on-site and in-shop electrostatic refinishing. Please help, companies' that made electrostatic paints are no longer permitted to sell or ship to NJ or NY. I have clients who want electrostatic painting to be done at there clients or facilities. Where do I go or what products are available. Please do not say waterborne, because the efficiency of water base paints and systems is not true and dry time is at least 3 times that of solvent based paints. A. Most solvent-based paints can be applied electrostatically, but you might need to insure that the paint of your choice contains some solvents that can carry an electrostatic current. All paint manufacturers make coatings that can be used directly, or that can be modified by adding the correct solvents. My suggestion is that you find a paint that you would like to use and measure its resistivity using a resistivity meter, such as are sold by companies such as ITW-Ransburg or Nordson. If the resistivity falls into the range required for the electrostatic spray gun that you are using, you can use the paint as-is. If the resistivity of the paint indicates that it does not carry a current (infinite resistivity - the pointer on the meter doesn't move) then call the paint manufacturer and ask which "polar" solvents you can add to increase the conductivity of the paint. The paint manufacturer should be able to tell you this, but you might need to play around with the solvent addition until you get a resistivity that falls into the recommended range. You must insure that when you add solvents, you do not exceed the VOC limit of the state regulations. The paint manufacturer will be able to tell you the maximum amount of solvent that you can add so that you don't violate the state regulation. Because you do not want to use a waterborne paint I have not covered this topic in this email. Good luck. Best wishes, Ron Joseph |