| 摘要 |
A combined sheet material including at least two absorbent sheets, such as of cellulose-cotton, each having a density of between from 10 to 40 g/m2. Each of the sheets is separately embossed by calendaring them into a pattern of protuberances distributed in a first pitch along a first direction for each sheet (P1sm, P2sm) and in a second pitch in a second direction for each sheet (P1st, P2st) which subtends the first direction at an angle other than zero. The end of the protuberances extending away from the plane of each of the sheets includes a flat bonding element whereby the two sheets are bonded to each other, preferably by gluing. The pattern of each of the sheets is characterized in that the first pitch of each sheet along the first direction is different and related by the equation. ¦1/P1sm-1/P2sm¦>/=1/L1 wherein L1 is a predetermined value corresponding to the dimension of a segment within the combined sheet material in which at least one spot capable of bonding the two sheets together is present regardless of the relative position of the two patterns.
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