CARBOXYMETHYL CELLULOSE OR SALT THEREOF, AND COMPOSITION THEREOF

Carboxymethyl cellulose or a salt thereof is adjusted to a form such that D10 is 90 um or higher, D50 is 120-470 um, and D90 is 500 um or lower, where D10, D50, and D90 are, respectively, the 10% cumulative, 50% cumulative, and 90% cumulative grain sizes from the small-grain-size side in the volume-based cumulative grain size distribution. D10 may be about 100 um or higher, D50 may be about 150-200 um, and D90 may be about 250 um or lower. In granular carboxymethyl cellulose or a salt thereof, the proportion of particles having a roundness of 50% or higher may be about 90 vol% or higher with respect to the whole, and the proportion of particles having a roundness of 70% or higher may be about 70 vol% with respect to the whole. The carboxymethyl cellulose or salt thereof can be dissolved efficiently in water even with gentle stirring. 本发明提供羧甲基纤维素或其盐，其中，将羧甲基纤维素或其盐调整为如下形式：在粒径的体积基准的累积分布中，从小粒径侧起累积10％、累积50％及累积90％的粒径分别设为D10、D50及D90时，D10为90μm以上、D50为120～470μm、D90为500μm以下。上述D10可以为100μm左右以上，D50可以为150～200μm左右，D90可以为250μm