MITRA Forum Question Details

Welcome

One of the first things you will realize here is that some of us…especially me, are sticklers for terminology. So, to start out, there is really no specific paint binder required to call a paint “poster color”. This could run the gamut from gum Arabic, to dextrin, to acrylic dispersions, to poly vinyl acetate, to practically anything. In the US the term was generally used to describe paints not intended for permanent uses, very often paints to be used for temporary posters announcing grocery store sales.

I watched the video and realize that this is not what the company is trying to convey. I believe that they are referring to a fluid, opaque gouache-like paint. There have been high quality gouache paint intended for illustration and the creation of advertising images. The paints were useful since they dried very matte and could be photographed without reflected hot spots. Casein paints were also used for the same purpose in the mid-20th century. As far as a gouache without additional fillers, most gouache paints had some sort of opacifier. They were essentially opaque watercolors which could be applied with some thickness without cracking. Most, if not all would contain a binder (gum Arabic or dextrin, later any number of binders) an opacifying material (often chalk), preservatives, humectants, and perhaps other additives. These were basically necessary to create a paint that would be opaque, not crack, and not putrefy in the tube or jar.

The paints in the video are in jars suggesting that they were quite fluid. This would also mean that they would need to be well thinned with water to prevent reticulation and delamination. Additionally, they probably also had some sort of stabilizer to prevent the pigment from settling out of the thinned mixture.

Additionally, I would like to state that animation cels using such water based binders have not always fared very well in the long term. Gums and starches are not especially good adhesives to keep pigments bound to sheets of acetate. I have seen numerous examples of whole sections of the paint delaminating from the support.

Finally, if you are intending to make your own colors to do traditional drawn animation, I would not suggest using simple pigments in Arabic. I would not even suggest a gum based binder. Likely, a proprietary paint made for the purpose with an acrylic or PVA binder would be far superior.

​Just a couple of thoughts: The desired properties described sound a lot like theatrical casein scenic paint. I mentioned this in correspondence with Brian, and he advised caution about the pigments used in scenic paints, which may not be permanent to the standards of artistic painting. With paints in that category, and for poster colors as well, it can be difficult to obtain information about pigment content. (The retired Utrecht Primary Artist Tempera Colors had a starch-based binder, in case anyone was curious.)