| 摘要 |
<p>Paper is made by forming a thick stock cellulosic suspension, flocculating the thick stock by adding a relatively high molecular weight and relatively low cationic charge density polymer, diluting the flocculated thick stock to form a thin stock and then draining the thin stock to form a sheet. Usually coagulant is added to the thin stock before drainage and best results are achieved by adding coagulant followed by anionic colloidal material such as bentonite. The process can be operated to give good retention and good formation and, if the thick stock is dirty, to minimise pitch problems.</p> |
