Re: Liquid Emulsion - Air Bubbles
From: Ritab19106@aol.com Subject: Liquid Emulsion - Air Bubbles Date: Tue, 28 Nov 2006 20:31:45 -0500 (EST) > I have consulted the Silver Emulsion bible (by Martin Reed) > and experimented with adding a few drops of glycerin and > also alcohol (Everclear) but neither seems to make much > difference. Glycerol and ethanol have little or no effect on this matter. Tertiary butyl alcohol and bigger alcohols work effectively as antifoaming agent. I don't use this technique but a bit of milk can be used to suppress foaming. There are some non-ionic surfactants that have reasonable defoaming power. I have some of such but they are proprietary compounds and they are very difficult to buy, unless in a ship-load of quantity. HOWEVER, some dishwasher (machine) rinsing agent (not detergent) is mostly a surfactant of low foaming power, and they may have some antifoaming activity if used in right quantity. Silicone oil emulsions (like Kremer defoamer) are a VERY effective defoamer but it's also easy to get defective coating (spots of poor coating or holidays) so be very careful when testing them. I used to use it but then phased out because of this problem.
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