| 摘要 |
<p>The sheet material, typically paper or cardboard, contains a natural, chemically untreated fibrous material and a secondary long-stapled fiber material in a weight ratio comprised between (50-90):(10-50). It further contains fiber fines, at least one retention agent for these fines and at least one sheet strength improving agent. The sheet may be manufactured on paper making machines after preparing a mash from the components listed above and refining. The sheet material is intended to replace paper or cardboard normally made from chemically treated, expensive raw materials.</p> |
