The application of durable press treatment to bleached softwood kraft handsheets

Graduation date: 1994There are several chemical treatments for paper to\ud Improve its strength properties. Durable press treatment is\ud usually used as a textile chemical finishing; however, there\ud is little information available on the application of durable\ud press treatment for paper. The durable press treatment was\ud applied to bleached softwood kraft handsheets using maleic\ud acid, citric acid and 1,2,3,4-butanetetracarboxylic acid\ud (BTCA) as crosslinking agents in this study. One catalyst\ud (NaH₂PO₄) was particularly effective toward promoting the\ud esterification reaction between handsheets and the\ud crosslinking agents. This reaction was confirmed by the\ud weight gain of the handsheets, by FT-IR spectroscopy, and by\ud the change in the paper properties. The wet strengths of\ud handsheets were improved significantly (as high as 63% of the\ud dry strength) when the BTCA WAS used as a crosslinking agent.\ud No tensile strength losses were found from BTCA and citric acid treatments, and the brightness of the handsheets\ud increased with durable press treatment. However, the fold\ud strength was severely affected by this treatment