This is the history that I learned over a phone conversation with Jonathan Talbot, an artist and author who was around in the early days of Acrylic Gel Medium Transfers. Fred Otnes was the first collage painter not Robert Rauschenberg according to Talbot. In the late 60’s and early 70’s another artist named Roderick Slater saw Otnes’ work and wanted to emulate his collage paintings. While he was experimenting with various techniques he noticed that acrylic medium that had stuck to magazines and newspapers would hold onto the image once the paper has been peeled up. Slater was able to take advantage of this property of acrylics and develop the Acrylic Gel Medium transfer technique. Slater taught Talbot the technique and they discovered that it worked best with paper that has been clay coated. The clay coating is basically a chalk that makes the paper opaque and is especially common in magazine paper. The clay protects the paper from being adhered by the Acrylic so only the ink layer is firmly attached to the medium.
Talbot, Jonathan. Telephone interview. 28 May 2013.