Abstract: The filter comprises a tobacco smoke filtration tube ensheathed in a layer of smoke pervious thermoplastic material. The layer is encased in a plugwrap. The layer has a transverse cross-section rendered impervious to smoke tobacco by use of an annular sealing groove. The tube is closed at a location spaced longitudinally from the groove by a V-shaped annular groove.

Abstract: A smoking article comprises a smoking material rod and, to one end thereof, a flow-impedance device comprising a rod-like element of foam or fibrous material which is or has been rendered impervious to the flow of smoke therethrough and one or more open-ended smoke-flow passages extending from one end to the other of the element, the pressure drop of the passage or passages being in the range from 40 to 200 mm, preferably 50 to 100 mm, water gauge and said device being enclosed in a wrapping permitting inward flow of ambient air into the device, which has air-conducting means whereby air flowing inwardly through the wrapping is conducted to the mouth end of the device, the device being effective to remove not more than 25%, preferably 20%, of the total particulate matter of the smoke. The passage or passages may be formed by a bore or bores in the material or by a capillary tube or tubes.

Abstract: Web-splicing apparatus comprises a web splicer and, associated therewith, an air mover and web-presentation means operable to present to the inlet end of the air mover the leading end of a first web extending from a reel and the leading end of a second web extending from another reel, which air mover is operable to feed the leading end of said first web from said presentation means to and through a splicing zone, to serve as a guide for subsequent continuous passage of that web and further operable to feed the leading end of the second said web from said presentation means to said splicing zone during continuous passage of the first web through the air mover. Web-severing means may be disposed for operation in the splicing zone and web-withdrawal means, suitably further air-mover means, downstream of that zone.

Abstract: A smoke-filter rod comprises a body of rod form consisting or having as at least major constituent a thermoplastics cellulose acetate or polypropylene smoke-filtration material, preferably of a fibrous or filamentary nature, and wrapped in a plugwrap comprising at least 50%, suitably at least 90%, by weight of fibres or filaments of, respectively, cellulose acetate or polypropylene material of substantially the same chemical identity as said major constituent of the filtration material, said plugwrap being bonded to said body and having a permeability for air of not less than 10,000 Coresta units. The bonding is by an agent which is a bonding agent for the material of said plugwrap and said filtration material, suitably triacetin in the case of cellulose acetate. Portions of such filter rod can be subjected to a hot-shaping process.

Abstract: A liquid-spraying device, particularly for applying an additive to a moving bed of smoking material. The device includes a body and an elongate narrow unshrouded tubular spray tip carried by the body. First and second ducts are in the body through which the liquid and an atomizing medium respectively can be supplied to the tip. A third duct is provided for supplying a cleaning medium such as air. A jet structure is located remotely from the discharge end of the spray tip, is connected to the third duct and is arranged to direct the cleaning medium along and around the outside of the freely extending tip to the discharge end thereof. The spray tip may be mounted on and extend from a nozzle head connected to the body. The jet structure is provided in the nozzle head, for example, in the form of a plurality of jet orifices equi-angularly spaced around the spray tip. The spray tip and jet can be used in a method of applying a liquid additive to a moving bed of smoking material.

Abstract: A rod-form body of smoke filtration material, preferably fibrous or filamentary, is wrapped in a fibrous or filamentary plugwrap comprising at least 50% by weight of fibres or filaments of thermoplastics material. The plugwrap may have premeability for air of not less than 10,000 Coresta units. The majority, suitably at least 80% by weight, of the material of the rod-form body is a material other than the said themoplastics material of the plugwrap. Thus the smoke-filtration material may comprise crimped polypropylene tow and the plugwrap be composed substantially wholly of fibrous cellulose acetate or conversely. Portions of such filter rod may be subjected to a hot-shaping process to provide grooved filter elements.

Abstract: A nitric oxide filtration material or filter, particularly for tobacco smoke, comprises activated carbon, preferably in particulate form, upon which has been absorbed a C-nitroso compound, any substituent group of said compound, other than a nitroso group, being such as to have no critical adverse effect on the integrity of the nitroso group. The compound is preferably an aromatic compound such as nitrosobenzene, 2-nitrosotoluene or 2,4, 6-trimethylnitrosobenzene. Suitably the carbon is coal-based. Advantageously the carbon has been loaded with a metal, such as copper or iron at a loading level in the range of 0.1% to 5% by weight on an untreated carbon basis. The loading level of the C-nitroso compound may be in the range of 2% to 15%, preferably 2% to 7% by weight. Such a filter comprising the C-nitroso compound may advantageously also comprise ventilation means.

Abstract: A smoking article comprises a rod of smoking material, wrapped in a wrapper, in which rod the packing density of the smoking material varies continuously along at least a major portion of the overall length of the rod, but is constant across any section, within said portion, in a plane perpendicular to the longitudinal axis. The smoking material may be of homogeneous constitution throughout the rod. Preferably the density decreases continuously along the said portion of the rod in the direction away from the end of the rod to be lit, from which end the said portion may extend to substantially the other end of the rod. There may be between a 5% and a 40% weight difference between the more dense half of the length of the rod and the less dense half thereof. The density at the less dense end of the rod may be in the range of 170 to 240 mg cm.sup.-3 and that at the denser end in the range of 290 to 350 mg cm.sup.-3.

Abstract: Apparatus and method for measuring the moisture content of a material, particularly a tobacco material, in which a microwave signal is divided between first and second signal paths, said first path comprising a sampling capacitor, the dielectric of which comprises the said material, and said second path comprising reference delay means, signals from each of the paths being fed to a phase detector providing an output indicative of waveform time displacement of one of said signals relative to the other of said signals. Advantageously signals from each of the said paths are fed through substantially identical first and second limiting amplifiers directly to the said phase detector. A second microwave signal of a frequency different from, but close to, that of the first-named microwave signal may be mixed with the signals from the sampling capacitor and from the reference delay means, the resultant beat signals of lower frequency being fed to the phase detector.

Abstract: The invention discloses a hinged-lid packet for cigarettes formed from a one-piece blank and having a body comprising a front wall panel, a rear wall panel and side wall panels. A lid is hingedly secured to the rear wall panel and has a front panel and inner and outer side wall panels on each side. The outer side wall panels are adhered to the outer faces of the associated inner panels only over a portion thereof so that the two panels on each side lie in a face-to-face relationship to provide gripping means for gripping, when the lid is closed, upstanding portions flaps on frame side panels extending upwardly from the side wall to thereby hold the lid closed.

Abstract: A tobacco-smoke filter comprises in admixture or close dispersion a first component which is a ready but weak or weakly retentive adsorbent for vapor-phase constituents, including aldehydes, of tobacco smoke, and a second component comprising amino groups, of which at least 30% are preferably primary groups, and being capable of chemically combining with said constituents to give substantially non-volatile reaction products. Suitably the first component may comprise a porous mineral earth, such as magnesium silicate or silica gel in porous granular form. The second component may comprise an ion-exchange resin or polyethylene imine. The second component may be carried upon a porous particulate material or carried or grafted upon a fibrous material or dispersed in a fibrous material carrying the second material in a dispersed condition. Alternatively, a mixture of granular first and second components may be dispersed in a fibrous or filamentary material or disposed between plugs of such material.

Abstract: For producing rod-shaped tobacco-smoke filter components each having one or more annular tobacco-smoke barriers, annular grooves open at their peripheries are formed in rod-shaped bodies of smoke-filtration material, the grooved bodies are conveyed in a direction transverse to their longitudinal axes along an arcuate path, and settable barrier material is deposited in the grooves during the conveyance along said path, the bodies being rotated about their said axes during the deposition of the barrier material.

Abstract: A method for obtaining a smoking material additive which is a smoke-aroma precursor comprises the steps of removing surface gum, preferably surface gum only, from Nicotinia plant leaves or flowers and subjecting the gum to a partition or purification process whereby a diterpene fraction constituting the said precursor and a fraction containing undesirable lipids are obtained, the latter fraction being discarded. The gum may be removed by solvent washing, suitably with chloroform. The partition or purification step may be a two-phase solvent partition process, for example using a hexane/aqueous methanol system.

Abstract: The invention comprises a method and apparatus for the detection, or detection and concentration determination, of nitric oxide in a gas mixture, particularly in tobacco smoke. The apparatus comprises sampling means operable to isolate a predetermined amount of the gas mixture and pass it to a reaction chamber, means for supplying to that chamber a further gas chemiluminescently reactable with the nitric oxide, and detection means responsive to luminescence emitted in the said chamber. The method comprises operating sampling means to isolate a predetermined amount of the gas mixture and supply it to a reaction chamber, supplying to that chamber a further gas chemiluminescently reactable with the nitric oxide, and operating means to detect luminescence in the said chamber. A carrier gas may be used for transferring the predetermined amount of gas mixture from the sampling means to the reaction chamber.

Abstract: The invention concerns a method of lap joining pieces of tobacco in which the said pieces are placed in overlapping relationship and the overlapping portions are adhered to each other, without using extraneous adhesive, by the application to them of pressure and/or rapid heating. Pressure may be applied between rollers or between jaws, particularly the jaws of an electrical impulse-heating machine. In this case, the overlapping portions lap joined by the rapid application of heat and pressure may be cooled while still held between the said jaws. Prior or subsequent to lap joining, a consolidating agent may be applied to end portions of the tobacco pieces.

Abstract: A tobacco-smoke filter comprises a plug of filter material of which a transverse cross section is impervious to the passage of smoke except for a minor proportion of the area of that cross section which forms a smoke-accelerating orifice, the plug being enclosed by an envelope permitting ingress of air into a region of the plug downstream of the orifice. The cross section may be impervious because of the presence of a barrier diaphragm of impervious material. Thus an annular groove may be provided in the plug at the cross section and may be filled with, or have its walls coated with, an impervious material. Alternatively the cross section may be impervious by reason of the closure of interstices in the filter material by the local application of heat thereto.

Abstract: A tobacco-smoke filter has a filter body comprising at least one intermediate section which is located between end sections, has a cross section less than that of the end sections and lies wholly within the outline of the latter sections as viewed axially of the body, and a porous wrap of sheet material which is pervious to volatile constituents of tobacco smoke and which bounds, with the said body, at least one space affording a path through which smoke can pass when the filter is in use and from which said constituents are removed fom the smoke by diffusion through the said sheet material, each of the said sections being made of filter material. Suitably the body is of generally cylindrical form and composed of cellulose acetate. Advantageously the intermediate section is integral with at least one end section.

Abstract: An instrument for measuring the air permeability of cigarette paper, including a paper-clamping head arranged to expose a fixed area of paper to a flow of pressurized air from an air pump. A manometer is arranged to measure the pressure differential across the paper and the gas flow is controllable by a control valve to enable a predetermined pressure differential to be maintained. The flow rate through the paper is measured by one of three flowmeters arranged in three parallel gas supply passages for measuring the flow rate in a low medium and high flow rate range respectively. The paper clamping head is such that the flow impedance downstream of the tapping point of the pressure transducer is negligible.

Abstract: The invention provides an arrangement for detecting faults in wrapped filter rod, for tobacco-smoke filtration, prior to its being cut into lengths, the arrangement comprises a light source and a light-sensitive receiver, for example a photo-transistor, in a housing provided with a rod guide which imposes on the rod a path between and spaced away from the said light source and receiver, a beam of light from the said source being projected through the said path of the rod to the receiver. Advantageously the housing bounds a cavity from which extraneous light is excluded and the light source and receiver are disposed behind respective transparent windows spaced away from the said rod path. The said receiver may be operatively connected to a system by which a faulty rod length detected is caused to be rejected after having been cut off from the rod.

Abstract: An improved tobacco-smoke filter or filter material contains granules of porous activated carbon to which has been applied a nitroxide of the group consisting of the nitroxide 4-oxo-2,2,6,6-tetramethylpiperidino-oxy, the nitroxide 1-nitronyl-3-oxyl-4,4,5,5-tetramethyl-2-phenyldihydroimidazole and mixtures thereof. The carbon may be loaded with 0.5 to 25%, suitably 1.0 to 15%, by weight of the nitroxide. Advantageously such a filter has provision for filter ventilation. For instance, in a triple filter with a center section containing the treated carbon, the said center section and/or the section upstream thereof is ventilated.