satisfactory results should be realized the inorganic filler material which is blended with the rigid polymeric material to form the aqueous dispersion is preferably a finely divided mineral filler of commercial grades which are sold for use in papermaking applications preferred particle sizes for the fillers range between 2 5 microns examples of mineral fillers which have been tested and found satisfactory are kaolin clay calcium carbonate mica and talc the amount of impregnant contained in the finished paper must be within a predetermined range for instance the impregnant should be between about 8 5 and about 50 by weight of the total finished weight of the paper on a dry solids basis if the amount of impregnant is below the lower limit the resulting paper has poor erasability on the other hand due to the density limitations of the base paper it is difficult to impregnate the paper beyond the upper limit preferably the impregnant is within a weight range of about 15 to about 40 the uncalendered finished density of the impregnated paper should be between about 10 5 and 14 0 lbs mil 500 sheets 24 u00d7 36 in in order to provide the desired physical properties of the paper of the present invention it is necessary for the rigid polymeric material to be extended within prescribed limits with one.