Patent DE-102008054957-A1 (DE)
Title: Method for the double side coating of running paper, cardboard or other fiber material web during its production and/or refinement process, comprises applying coating medium such as starch on fiber material web in direct manner
Inventor: MENDEZ BENJAMIN
IPC: D21H23/56
Filed: 2008-12-19
Abstract: The method comprises applying coating medium such as starch on running paper, cardboard or other fiber material web (1) in direct manner. A first rotatable transfer element (3) is associated to a first coating aggregate (6) and a second rotatable transfer element (4) is associated to a second coating aggregate (7), where both transfer elements form a press gap (5) through which the fiber material web to be coated is passed. The transfer element transfers the coating medium on respective side of the fiber material web moved in direction. The method comprises applying coating medium such as starch on running paper, cardboard or other fiber material web (1) in direct manner. A first rotatable transfer element (3) is associated to a first coating aggregate (6) and a second rotatable transfer element (4) is associated to a second coating aggregate (7), where both transfer elements form a press gap (5) through which the fiber material web to be coated is passed. The transfer element transfers the coating medium on respective side of the fiber material web moved in direction. The fiber material web is guided to both transfer elements in S-shaped manner in such a way that the coating medium applied on the first transfer element influences with a retention time on the relevant web side and is pressed in the press gap in the web side. The coating medium applied on the second transfer element is pressed first in the press gap into another web side and then subjected with a retention time of 1-100 msec before both sides of the fiber material web are subjected to contact drying by drying cylinder (10). The fiber material web entangles the transfer element respectively in an angle area of 270[deg] . Coating rollers are used as transfer elements, where the roll hardness is 40 P&J. The diameter of the coating roller is 800-1800 mm and the coating roller forms a Niplast of 15 kN/m. The coating medium is supplied in a quantity of 5-100 ml/web side. The fiber material web is guided by second transfer element over a deflecting roller to a further treatment location such as contact drying. The fiber material web expiring by the deflecting roller is supported on the web side in a straight section by a rotating endless band. The supporting is carried out by the endless band up to contact drying. An intermediate drying is carried out during supporting with the endless band. The intermediate drying is carried out in the form an air- and/or infrared drying or contact drying. The coating medium applied on the fiber material web is pressed by additional pressing body in the fiber material web during the supporting. Starch is used as coating medium. A double layer of the coating medium is applied on the web side with a further coating aggregate, which is associated to the endless band. The fiber material web is treated in the form of raw paper web with high waste paper portion.