WET END STARCH APPLICATION

摘要

A method of applying a starch sizing to a forming web on a paper machine, such as in the form of a curtain on a fourdrinier machine, employs a suspension of uncooked particulate starch and water which is applied, as a suspension, to the inlet of a downwardly opening die positioned over the forming web and applied at a consistency of between about 2 to 10% onto the surface of the web as a free falling curtain, the impact velocity of which is controlled to a rate sufficiently low to prevent distortion of the web on impact. Improved drainage is achieved by heating the suspension to a temperature less than about 150 DEG , to prevent the cooking of the starched particles. The curtain may be applied to the web at fourdrinier table consistencies as low as about 2% and still obtain starch retention rates of about 80%.