Latex Spraying Revisited

I read the letter from G.S. in the August issue concerning the spraying of a latex.


Q. I read the letter from G.S. in the August issue concerning the spraying of a latex. If I remember correctly, a latex is an emulsion and retains its characteristics in another liquid. They are difficult to spray since they do not break down in the other liquid. It is not like a solution where one disperses into the other liquid to form a homogeneous liquid.

I wonder what product he is spraying and why he is using a latex. He can get a reasonably fast air-dry material, use a two-part system to cure quickly or probably get a waterborne material that will dry reasonably fast. If he were willing to use a solvent-reduced material, he would have even more options. I get the feeling his volume is very small, and he is using an off-the-shelf material. S.B.

A. For the most part, your comments are true. According to the Coatings Encyclopedic Dictionary (CED), an emulsion is a “two-phase liquid system in which small droplets of one liquid (the internal phase) are immiscible in, and are dispersed uniformly throughout, a second continuous liquid phase (the external phase).” The CED also defines a latex as a “stable dispersion of a polymeric substance in an essentially aqueous medium.” It goes on to say, “Strictly speaking, after polymerization, a latex is a solid dispersed in water and, therefore is not an emulsion.” Latex and emulsions are often used synonymously in the paint industry.
Furthermore, G.S. is not developing a coating but a new type of high-volume, low-pressure (HVLP) spray gun. His problem is atomizing a typical latex paint using his experimental HVLP spray gun. 

Related Content

Chemcoaters Names Mike Tieri VP of Sales and Marketing

Effective immediately, Chemcoaters appoints appoints Mike Tieri as vice president of sales and marketing.