Abstract: Method and apparatus for the manufacture of cigarette filters containing particulate material. Filter material composed of cellulose acetate tow is fed in the axial direction through a gap defined between a first pair of rolls so that the transverse cross-section of the filter material is changed to a substantially oval shape. The filter material is then fed through another gap defined between a second pair of rolls so that the transverse cross-section of the filter material is further changed to a substantially heart shape and at the same time providing pockets at axially spaced positions. Particulate material is deposited in said pockets. The filter material is closed so that the deposited particulate material is positioned in the interior of the filter material and wrapped with wrapping sheets.

Abstract: Disclosed is a method and an apparatus for conducting measurements on at least two physical properties, such as resistance to air permeation, diameter, weight, hardness and length, of cigarette filters. At least two measuring devices are used for conducting the measurement of designated properties, respectively.

Abstract: Asymmetric hollow fibers useful for effecting separations are prepared by spinning a solution of a fiber-forming cellulose derivative through the outer tube of a double tube-type spinneret into an aqueous coagulating bath to form a hollow fiber and simultaneously injecting an aqueous salt solution through the inner tube of the spinneret to contact the interior of the hollow fiber. The hollow fibers are dipped in warm water, then the free water is removed and the fibers are frozen and dried under vacuum.

Abstract: A nonwoven cellulose acetate laminate is made from a base material mainly composed of a cellulose acetate fiber web, in a short time, by the steps of: impregnating a liquid initial condensate of phenol-formaldehyde into the web or spraying a powdery condensate of phenol-formaldehyde onto the web, and then penetrating superheated steam through the resultant cellulose acetate laminate sheet. The sheet possesses good mechanical properties and excellent sound-absorbing and heat-insulating characteristics.