The filterability of the viscose prepared by the emulsion xanthation process was compared with that of the viscose prepared by conventional process. If emulsion xanthation is performed under suitable conditions concerning the amount of CS2 and NaOH concentration, the filterabilities of the viscoses prepared by both processes are fairly correlative. In this case, most suitable conditionss of emulsion xanthation are as follows.When sheet-formed pulp was used 12g (bone-dry) of air dried pulp which is remade into loose sheet in distilled water, 324 cc of 13% NaOH and two varying additions of CS2 (90% and 170% basis pulp) were simultaneously shaken in stoppered glass bottle for 4 hrs. at 20C°. Sample was ripened over night at 20°C, and filtered through 5 sheets of carico under the pressure of 40 cm height of mercury, and clogging constant (KW) was calculated.Furthermore, emulsion xanthation of alkali cellulose which were aged according to conventional process and so-called sulfidation-resistance according to Bartunek's method were also studied.