abstract |
The invention relates to a method for manufacturing paper, paperboard or cardboard comprising the steps ofn (a) pulping an aqueous cellulosic material containing a starch; (b) preventing at least a portion of the starch from being microbially degraded by treating the aqueous cellulosic material containing the starch with one or more biocides; and (h) adding a dry and/or wet strength polymer to the cellulosic material. |