Lindy said:
Copper soap, aka copper oleate, is one of many heavy-metal soaps. I learned quite a bit about these when I studied oil painting & chemistry as a hobby...
Maybe most posters to this board know the difference between sodium and potassium, but it never ceases to amaze me how many people don't. But I digress... heavy-metal soaps are generally insoluble in water. These include calcium soap (which was made from linseed oil soap and used in the old days as putty), aluminum stearate soap (which was mixed with gasoline to make napalm in the Vietnam War era), copper soaps which are used as fungicidal paints, chromium oleate soap which is used as an anti-chalking agent in oil paints, cobalt & manganese soaps which are used as driers for oil paints and japan varnishes, zirconium oleate soaps used as anti-brittling agents for oil paints, and lead and mercury soaps which are toxic and no longer used.
To make a copper soap, simply grate ordinary soap into hot water until it all dissolves, then add a solution of copper sulfate (aka Roebic's Root Killer from the hardware store). A dark blue-green goop will form, and it will float to the top of the pot. This is copper oleate. Let the whole pot cool, break the copper oleate into chunks with an ice pick, and dissolve it in paint thinner to make a green stain for wood which will keep fungus and rot from attacking it. To make any of the other soaps, substitute their soluble salts (e.g., calcium chloride, chrome alum, etc) for Roebic's Root Killer.
In industry, heavy-metal soaps are often made from naphthenic acid... this is a thick amber liquid which is extracted from petroleum and smells like roofing tar. I've also made paint-drier soaps out of tall oil, which comes from pine trees.
So... I may be a newbie, but if you have a question about exotic soaps, I might be able to provide you with answers.
