Watercolor painting to paints that use water-soluble, complex carbohydrates as a binder. Originally (in the 16th to 18th centuries), watercolor binders were sugars and/or hide glues, but since the 19th century, the preferred binder is natural gum arabic, with glycerin and/or honey as additives to improve plasticity and solubility of the binder, and with other chemicals added to improve product shelf life. The term "bodycolor" refers to paint that is opaque rather than transparent. It usually refers to opaque watercolor, known as gouache. Modern acrylic paints use a acrylic resin dispersion as a binder. Watercolor painters before the turn of the 18th
Gum over platinum acid, the print is washed in 1% potassium metabisulfite after proper development in water. Interested individuals should read up on the process before attempting, as the chromic acids are very dangerous to work with. The mechanics of the gum portion is not entirely known; what occurs is the exposed gum is hardened and becomes water-insoluble. Upon washing, the unexposed portions wash away, leaving the white paper exposed. The technique is related to platinum printing. Gum over platinum Gum over platinum is a historical chemical photographic process, which was commonly used in art photography. It is a very complex process, in