NATURAL PAPER STRENGTHENING AGENT, AND METHOD FOR PRODUCING PAPERBOARD USING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide an environment-friendly method for papermaking by which high freeness and starch retention are developed to thereby manifest high paper strength without deteriorating operation efficiency and practice can be made with simple equipment though the amount of a synthetic paper strengthening agent used is suppressed to the necessity minimum for taking the environment into consideration and starch which is a natural product as a substitute therefor is used as a paper strengthening agent because problems that pulp fibers are micronized by recycling of used paper and sufficient paper strength is difficult to obtain come to be created though reutilization of the used paper is promoted from the necessity of effective utilization of resources and environmental protection in the papermaking industry. SOLUTION: A cationic synthetic paper strengthening agent in an amount of the necessity minimum is added to a pulp slurry, and a paper strengthening agent derived from the natural product composed of starch particles mixed with anionic fine particles in the state of a slurry is then added thereto. COPYRIGHT: (C)2009,JPO&INPIT