The invention relates to the technical field of
papermaking methods, especially to a production method of a kraft
cardboard with an ultra low
gram weight. The method comprises the following technological steps of: conducting batching; adding water for disintegrating so as to obtain a
slurry; carrying out combined purification treatment to the
slurry; performing moderate concentration beating; adding a chemical
system into the combined
slurry;
papermaking; molding
filtration water for
papermaking; implementing two-stage squeezing
dewatering; conducting primary baking for
drying; carrying out
sizing; performing further baking for
drying; implementing
calendering; and conducting coiling. The invention effectively solves the problems of low grade, poor strength, high
pollution load of discharged
sewage, large
gram weight, incomplete treatment to
viscose materials and
hot melt materials in
waste paper, large process investment and other problems in existing kraft cardboards. The production method of a kraft
cardboard with an ultra low
gram weight in the invention makes use of a combined technology of pulping and papermaking, and fully utilizes secondary fibers to prepare a kraft
cardboard with an ultra low gram weight through papermaking, so that the
fiber consumption is reduced. And the prepared kraft cardboard has high strength and a gram weight of 90g / m<2>. The method provided in the invention has high vehicle operation speed, reduces production cost and
energy consumption, decreases
pollutant discharge, and enhances
economic benefits.