DEGRADATED HYDROPHOBIC PARTICULATE STARCH AND ITS USE IN PAPER SIZING

摘要

PROBLEM TO BE SOLVED: To provide a method of decreasing polarity, increasing the resistance against liquid permeability and increasing surface strength in a paper material by applying a particulate starch which has been processed into a hydrophobic state, degradated and hydrated, together with a surface sizing composition containing the starch in an effective amount, on the surface of the paper material.;SOLUTION: The particulate starch is obtained by the following processes: degradating a starch base material into a state in which the starch has a water fluidity(WF) of about 10-80 or degradating a processed and/or particulate starch using a degradating agent of a substantially equivalent amount, under conditions substantially identical to the above; treating the resultant starch with a 5-23C hydrophobic hydrocarbon at a substitution level of about 1-20% the weigh of the bound hydrophobic material based on the weigh of the starch; and hydrating. The resultant particulate starch has as least about 20 μm of a volume average hydrated particle size and a volume fraction of the hydrated particle of about 5% at a solid fraction of 1%.;COPYRIGHT: (C)2001,JPO