Carboxymethylated cellulose
AssigneeNippon Paper Industries Co., Ltd.
InventorsKazuhiko Inoue, Takeshi Nakatani, Yusuke Tada, Kasumi Nishigaya, Hiroyoshi Suzuki
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Abstract
A carboxymethylated cellulose having a carboxymethyl substitution of no more than 0.50 and a cellulose I type crystallization of at least 50%. Ideally, the anionization is 0.00-1.00 meq/g. The Schopper-Riegler freeness is ideally at least 60.0° SR. Ideally the ratio of filtration residue is 0%-30% by mass. The viscosity (30 rpm, 25° C.) for an aqueous dispersion having a 1% solid content (w/v) is ideally no more than 10.0 mPa·s.
Claims11
A carboxymethylated cellulose having a degree of carboxymethyl substitution of 0.50 or less, a degree of crystallization of cellulose I type of 50% or more, and a portion of a filter cake being 0 to 30%, wherein the portion of the filter cake is determined by a method comprising the steps of:
- adding 5 g of the carboxymethylated cellulose to 500 g of water to obtain a mixture,
- stirring the mixture at 400 rpm for 5 seconds,
- subjecting the stirred mixture to natural filtration through a 20-mesh filter to obtain the filter cake on the filter,
- drying the filter cake on the filter at 100° C. for 2 hours,
- determining an absolute dry mass (g) of the filter cake,
- determining an amount of moisture (%) in the carboxymethylated cellulose, and
- calculating the proportion of the filter cake by using the following expression:
- proportion (%) of filter cake=[the absolute dry mass (g) of filter cake/{5 (g)×(100−the amount of moisture (%) in the carboxymethylated cellulose)/100}]×100.
Dependencies are inferred from the claim text.