is paper and the compounds of formula i are to be used as external or surface paper sizing agents one preferred method of contacting is to apply aqueous paper stock with an aqueous emulsion comprising the active compounds of formula i the aqueous paper stock may be produced by any conventional process for example mechanical pulp semichemical pulp or chemical pulp the paper or pulp from which it was made may be bleached semibleached or unbleached or combination thereof and may contain fillers or pigments such as clays e g kaolin calcium carbonate titanium dioxide calcium sulfate talc diatomaceous earth or zinc oxide a more detailed description of external or surface sizing of paper may be found in james p casey pulp and paper chemistry and chemical technology third edition volume iii chapter 20 34 surface sizing 34 pages 1687 1794 this chapter is incorporated herein by reference in its entirety if the cellulosic material is paper pulp and the compounds of formula i are to be used as internal paper sizing agents then an aqueous emulsion containing the sizing agent may preferably contact the pulp under moderately acidic conditions through neutral to slightly alkaline conditions i e a ph from about 4 to.