Date of Award
Bachelor of Science
Pulp and Paper Technology
Robert T. Elias
A literature survey is presented concerning the yellowing of paper with age and the relationships of rosin, light, and iron as factors in inducing this discoloration. The recent chemical modifications of rosin which are applicable for use in the sizing of paper are investigated with the intent of discerning whether or not they exhibit sufficient improvement in color-brightness stability over that of natural rosin to warrant their use in certain high quality papers.
The experimental results indicated only one rosin modification, "Foral", a fully-hydrogenated rosin, having a marked advantage over natural rosin with regard to brightness stability as affected by light and iron under the conditions of this work. A partially-hydrogenated rosin, "Staybelite", displayed only a slight improvement over the stability of the high grades of natural rosin, WG and WW.
Janes, Raymond L., "A Comparison of the Color Stability of Certain Rosin Sizing Agents as Influenced by Light and Iron" (1953). Paper Engineering Senior Theses. 277.