Abstract: A filter for a cigarette includes a porous filter rod circumscribed by a substantially non-porous or air impermeable wrapper with selected air permeable areas, and ventilating air grooves embedded in the wrapped filter rod which extend from on end of the filter rod a preselected distance generally longitudinally of the filter rod. Tipping material circumscribes the wrapped filter rod and is formed with perforations therethrough providing a path for ventilating air flow into the grooves and into the body of the filter rod at the selected air permeable areas outside of the grooves. The walls of each of the grooves are formed with preselected perforations therethrough to provide for the flow of air from the grooves into the body of the filter rod. Under certain smoking conditions most, if not all, of the ventilating air in the grooves will flow from the grooves into the smoker's mouth through the open end of the grooves at the mouth end of the filter rod.

Abstract: A filter for a cigarette which includes a centrally disposed generally conical baffle at the mouth end thereof with its conically shaped wall diverging in the general direction of the flow of smoke through the filter to divert the smoke exiting from the center of the filter when in use. The baffle is substantially impervious to smoke and forces the smoke leaving the filter in a direction generally angularly outward from the periphery of the filter. Ventilating air grooves can also be provided in the filter to direct ventilating air at the mouth end of the filter to provide mixing of the exiting smoke and ventilating air at the mouth end of the filter.

Abstract: A filter for a cigarette includes a generally cylindrical permeable filter rod circumscribed by an air permeable tipping material with a plurality of blind-end channels formed in the filter rod, each of the channels being open at one end to the upstream end of the filter rod and extending therefrom, generally in the longitudinal direction of the filter rod, a predetermined distance less than the length of the filter rod.

Abstract: A filter for a cigarette includes a porous filter rod circumscribed by a porous or air permeable wrapper, and ventilating air grooves embedded in the wrapped filter rod which extend from one end of the filter rod a preselected distance generally longitudinally thereof. The wall of each of the grooves defined by the wrapper is impermeable to air and smoke while at least a portion of the remaining area of the wrapper is air permeable. An air permeable tipping material circumscribes the wrapped filter rod which provides a path for ventilating air flow into the filter rod and a path for air flow into the grooves. Due to the air impermeable wall of the grooves, the air flowing in the grooves is segregated from the air and smoke flowing through the filter rod so that ventilating air is the only substance flowing in the grooves. The air flowing through the tipping material into the filter rod co-mingles with and dilutes the smoke flowing through the filter rod before it reaches the smoker's mouth.