Method for the production of magazine paper from fiber material suspension, comprises grinding lignocellulosic, bleached, high strength fiber material from wood or annual plants

摘要

The method for the production of magazine paper from fiber material suspension, comprises grinding lignocellulosic, bleached, high strength fiber material from wood or annual plants with a power of 250 kWh/t. The material suspension consists of de-inked wastepaper and a portion of 5-50% of lignocellulosic, bleached, high strength fiber material from wood or annual plants that have a breaking length of 7.5 km at 15[deg] SR and a lignin content of 13% related to the fiber material for soft wood, in unground condition. The method for the production of magazine paper from fiber material suspension, comprises grinding lignocellulosic, bleached, high strength fiber material from wood or annual plants with a power of 250 kWh/t. The material suspension consists of de-inked wastepaper and a portion of 5-50% of lignocellulosic, bleached, high strength fiber material from wood or annual plants that have a breaking length of 7.5 km at 15[deg] SR and a lignin content of 13% related to the fiber material for soft wood, in unground condition or a breaking length of greater than 5.0 km at 20[deg] SR and a lignin content of 10% related to the fiber material for hardwood, in bleached condition, or a breaking length of greater than 4.0 km at 20[deg] SR and a lignin content of 10% related to the fiber material for annual plants in bleached condition. Another fiber material is formed by stone groundwood pulp, thermomechanical pulp, bleached chemi-thermo-mechanical pulp, chemithermo mechanical pulp and/or alkaline peroxide mechanical pulp. The breaking length is greater than 10 km for softwood-fiber-mass at 15[deg] SR, is greater than 5.5 km for hardwood fiber mass at 20[deg] SR or is greater than 5.5 km for annual plant-fiber mass at 20[deg] SR. The portion of high strength fiber material is 10-25% and the portion of the another fiber material is less than 15%. The portion of the de-inked wastepaper on total fiber material is greater than 80%. The high strength fiber material is produced from eucalyptus or aspen tree. The softwood-fiber mass is ground with a power of 250 kWh/t. The high strength fiber material in the softwood-fiber mass is ground with a power of 280 kWh/t. The ground, high strength fiber material in the softwood-fiber mass has a breaking length of 8.6 km at a grinding degree of 16[deg] SR. The ground, high strength fiber material in the hardwood-fiber mass has a breaking length of 6.5 at a grinding degree of 30[deg] SR. The high strength fiber material is bleached up to 80% white.