Abstract: The invention relates to a longitudinally creped paper web for use in the manufacture of filter rods. In order to improve the filtering capacity and resistance to flow therethrough without weakening filter plugs formed from the web in respect of resistance to radial crushing the longitudinally creped web is provided wth linear indentations transversely thereof which are sufficiently closely spaced one from the other longitudinally of the web to provide consistency in draw of short length sections cut from filter plugs made from the web. The invention also relates to the process and apparatus for forming such a filter web using co-operating spaced rollers for forming controlled linear compression zones extending transversely of the web, at least one of these two rollers being provided with ribs extending at least approximately axially of the roll.

Abstract: The invention relates to a longitudinally creped paper web for use in the manufacture of filter rods. In order to improve the filtering capacity and resistance to flow therethrough without weakening filter plugs formed from the web in respect of resistance to radial crushing the longitudinally creped web is provided with linear indentations transversely thereof which are sufficiently closely spaced one from the other longitudinally of the web to provide consistency in draw of short length sections cut from filter plugs made from the web. The invention also relates to the process and apparatus for forming such a filter web using co-operating spaced rollers for forming controlled linear compression zones extending transversely of the web, at least one of these two rollers being provided with ribs extending at least approximately axially of the roll.

Abstract: The invention relates to a longitudinally creped paper web for use in the manufacture of filter rods. In order to improve the filtering capacity and resistance to flow therethrough without weakening filter plugs formed from the web in respect of resistance to radial crushing the longitudinally creped web is provided with linear indentations transversely thereof which are sufficiently closely spaced one from the other longitudinally of the web to provide consistency in draw of short length sections cut from filter plugs made from the web. The invention also relates to the process and apparatus for forming such a filter web using co-operating spaced rollers for forming controlled linear compression zones extending transversely of the web, at least one of these two rollers being provided with ribs extending at least approximately axially of the roll.

Abstract: Improved apparatus for treating a web of fibrous material, usually paper, to render it particularly suitable for making filter plugs for cigarettes, including at least one first pair of meshing rotating rolls provided with longitudinal grooves alternating with longitudinal ribs, which engage the paper and stretch it longitudinally in closely spaced successive narrow transverse areas to loosen and expose fibers without impairing the longitudinal continuity of the paper, and at least one second pair of meshing rotating rolls provided with circumferential grooves alternating with circumferential ribs, which engage the paper and groove it in a direction parallel to its travel while also stretching it transversely to further loosen and expose fibers without impairing the transverse continuity of the web. Preferably the apparatus also includes means for moistening the paper in advance of its passage through the rolls and for drying it after its passage therethrough.

Abstract: An elongated web of paper is treated to render it especially suitable for being gathered transversely and wrapped to make cigarette filters. The treatment includes passing the web through the bight between a pair of rotating rolls provided with intermeshing ribs that do not contact one another and which are arranged generally in planes parallel to their axis of rotation so that the paper is stretched longitudinally in successive transverse areas whereby the paper fibers are loosened and exposed in such areas without complete destruction of the longitudinal continuity of the web.