| 摘要 |
Corrugated cardboards are stiffened by treating the papers before they pass between the corrugating cylinders with an aqueous solution of glyoxal containing a polygalacto-mannose and a condensation catalyst. The polygalactomannose may be guar gum or carob gum, and the condensation catalyst may be an acid or compound capable of producing an acid during the treatment, e.g. a chloride or sulphate of a metal other than an alkali metal, in particular aluminium sulphate. The glyoxal, as polyhydrate, guar gum and catalyst can be mixed in powder form and stored until required for use. The specification also describes for purposes of comparison paper treated with glyoxal and catalyst without the polygalactomannose. |
