# US 2008/0185011 A1 · Sealed cigarette filter > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2008/0185011 A1 - Document ID: US20080185011A1 - Status: Published application - Kind: A1 - Application number: 12/000,865 - Filed: 2007-12-18 - Published: 2008-08-07 - Earliest claimed: 2006-12-29 - Assignees: Philip Morris USA Inc. - Inventors: Timothy S. Sherwood - Web page: https://patentgrep.com/patent/US20080185011A1 ## CPC - A24D 3/048: {containing additives} - A24D 3/0225: {with solid additives, e.g. incorporation of a granular product (A24D3/0216 takes precedence)} - A24D 3/061: {containing additives entrapped within capsules, sponge-like material or the like, for further release upon smoking} - A24D: CIGARS; CIGARETTES; TOBACCO SMOKE FILTERS; MOUTHPIECES OF CIGARS OR CIGARETTES; MANUFACTURE OF TOBACCO SMOKE FILTERS OR MOUTHPIECES ## Abstract Smoking articles, such as cigarettes and cigarette filters, methods of manufacturing smoking articles including sealed filters, and methods of treating tobacco smoke are provided. In one exemplary embodiment, a smoking article contains sealed filters, wherein additives are sealed within the sealed filters. ## Claims ### Claim 1 A cigarette, comprising: a tobacco rod; a sealed filter adjacent to a downstream end of the tobacco rod, wherein the sealed filter comprises: a housing with a stepped inner profile; a cavity within the housing; a first film sealing an upstream end of the cavity on a first step of the stepped inner profile; and a second film sealing a downstream end of the cavity on a second step of the stepped inner profile, wherein the cavity is located between the first film and the second film sealing a downstream end of the cavity; and tipping paper attaching the tobacco rod to the sealed filter. ### Claim 2 (depends on 1) The cigarette of claim 1, wherein the sealed filter further comprises: a first screen upstream of the first film; a second screen downstream of the first film; a third screen upstream of the second film; and a fourth screen downstream of the second film. ### Claim 3 (depends on 2) The cigarette of claim 2, wherein each of the screens are located on a stepped portion of the housing, and/or wherein the screens are attached to the housing by mechanical attachment or chemical bonding. ### Claim 4 (depends on 1) The cigarette of claim 1, wherein the sealed filter further comprises: one or more additives within the cavity of the filter, wherein the one or more additives comprise flavors, neutralizing agents, chemical reagents, catalysts, sorbents, and/or diluents. ### Claim 5 (depends on 1) The cigarette of claim 1, further comprising at least one piercing device operable to pierce the first film and/or the second film upon a suction force being applied to a downstream end of the filter. ### Claim 6 (depends on 1) The cigarette of claim 1, wherein the first film and/or the second film comprise: an elastomeric polymer; and/or a scored film. ### Claim 7 (depends on 1) The cigarette of claim 1, wherein the housing, the first film and the second film are of non-permeable material. ### Claim 8 (depends on 1) The cigarette of claim 1, wherein: the sealed filter further comprises at least one additional cavity, and at least one additional film; and/or the cigarette further comprises at least one additional sealed filter and/or at least one non-sealed filter. ### Claim 9 A sealed cigarette filter, comprising: a housing; a cavity within the housing; a first film on a first side of the cavity; a second film on a second side of the cavity; and at least one piercing device located next to the first film and/or the second film. ### Claim 10 (depends on 9) The sealed cigarette filter of claim 9, wherein the at least one piercing device comprises a pointed pin that pierces the first film and/or the second film to rupture the first film and/or the second film, respectively. ### Claim 11 (depends on 9) The sealed cigarette filter of claim 9, further comprising at least one screen, wherein the at least piercing device is part of or attached to the at least one screen. ### Claim 12 (depends on 9) The sealed cigarette filter of claim 9, further comprising: a first screen located adjacent to the first film; a second screen located adjacent to the first film and on the opposite side of the first film from the first screen; a third screen located adjacent to the second film; and a fourth screen located adjacent to the second film and on the opposite side of the second film from the third screen; wherein one of the at least one piercing device is located on the second screen and wherein a second one of the at least one piercing device is located on the fourth screen. ### Claim 13 (depends on 9) The sealed cigarette filter of claim 9, further comprising: additives within the cavity of the filter, wherein the additives comprise flavors, neutralizing agents, chemical reagents, catalysts, sorbents, and/or diluents. ### Claim 14 (depends on 9) The sealed cigarette filter of claim 9, wherein the first film and/or the second film comprise: an elastomeric polymer; and/or a scored film. ### Claim 15 (depends on 9) The sealed cigarette filter of claim 9, wherein the housing, the first film and the second film are non-permeable. ### Claim 16 (depends on 9) The sealed cigarette filter of claim 9, further comprising: at least one additional cavity; and at least one additional film. ### Claim 17 (depends on 1) A method of treating tobacco smoke produced by the cigarette of claim 1, comprising: drawing on the cigarette so as to rupture the first film and the second film; lighting or heating the tobacco rod to form smoke; and drawing the smoke through the cavity, wherein the cavity includes additives therein which interact with the smoke. ### Claim 18 (depends on 17) The method of claim 17, wherein the additives comprise sorbent, and the sorbent removes constituents from the smoke; and/or wherein the additives comprise one or more flavors, neutralizing agents, chemical reagents, catalysts, and/or diluents, and wherein the additives interact with the smoke.