| 摘要 |
Fibers with a freeness of 550 - 950 ml CSF are incorporated in a bulk-promoting layer of a paper or paperboard laminate, in combination with a secondary layer on one or both sides of the bulk layer. A paper or paperboard laminate (1) comprises at least one bulk-promoting layer (2), in combination with a secondary layer (3) on one or both sides of (2). (2) and (3) are joint together directly or indirectly by their surfaces facing one another. 40 - 95% of (1) consists of cellulose fibers with a freeness of 550 - 950 ml CSF. (3) is denser than (2), and (1) has a bending stiffness index higher than 2.5 Nm7/kg3, but less than 14 Nm7/kg3, calculated as a geometric mean value for machine and transverse direction. An Independent claim is also included for the production of (1) which comprises production of (2) and joining at least on its one side directly or indirectly (3). |
