| 摘要 |
1515865 Treating mechanical pulp PAPIRINDUSTRIENS FORSKNING-SINSTITUTT 12 Sept 1975 [12 Sept 1974] 37605/75 Heading D2W Mechanical wood pulp is impregnated with a buffer agent (other than a borate) which buffers in the pH range 6-10, the buffer agent being present in an amount of at least 0.2% by wt., based on the dry wt. of the pulp. The buffer, which may be added in the form of an aqueous solution, may be introduced into a refiner or grinder, the white water system of a paper machine, or by injection into the pulp. The buffer may be an alkali metal salt or ammonium salt of phosphoric acid, carbonic acid, citric acid or tartaric acid. The examples describe the use of sodium phosphate, ammonium carbonate, sodium citrate, and sodium borate (for comparison only) buffer solutions. The mechanical pulp may be a refiner pulp, ground wood pulp or, a thermomechanical pulp, which may have been treated with ozone. The treated pulps are stated to be easily wet defiberised, and show a high water absorption rate. |
