WO1986004488A1

WO1986004488A1 - Self-extinguishing cigarette

Info

Publication number: WO1986004488A1
Application number: PCT/DK1986/000013
Authority: WO
Inventors: Kaj Berg Jensen
Original assignee: Kaj Berg Jensen
Priority date: 1985-02-05
Filing date: 1986-02-04
Publication date: 1986-08-14
Also published as: DK49985D0; EP0210267A1; AU5514986A

Abstract

A self-extinguishing cigarette comprising a tubular outer wrapper surrounding a tobacco rod or column is provided with a non-collapsible elongated ampoule, which will break, soften, fuse or burn when exposed to heat, containing a non-inflammable liquid medium in a sufficient amount to extinguish the glow in the cigarette when liberated from the ampoule and arranged coaxially at the mouth end and within the body of the cigarette.

Description

Self-extinguishing cigarette

The invention relates to a self-extinguishing cigarette.

It is well-known that a discarded smouldering cigarette can be unpleasant and dangerous because the cigarette may continue to smoulder and burn after the smoking has been discontinued.

The unpleasant aspects consist primarily in bad smell and odour produced during the slow burning of the dis¬ carded cigarette. The dangerous aspects consist in dif¬ ferent types of serious fire hazards. Smouldering ciga- rettes in ashtrays have caused numerous fires which have resulted in complete destruction of buildings, ships, etc., e.g. when ashtrays with still smouldering cigarettes have been emptied in containers containing inflammable materials; and smouldering cigarettes dis- carded on the ground have caused numerous large and devastating fires in forests and fields.

These inconveniences and hazards could be eliminated or at least minimized if it was possible to provide a reliable self-extinguishing cigarette, which in the present context is defined as a cigarette having the ability of extinguishing itself at the moment when the glow arrives at a predetermined position on its way towards the mouth end of the cigarette. A further advan- tage of a self-extinguishing cigarette consists in the possibility of arranging the extinguishing position at such a point that it is impossible to smoke the last part of the cigarette, which is acknowledged as being the most dangerous, seen from a medical point of view.

In GB patent specification no. 245,329 it has been pro- posed to provide a self-extinguishing cigarette comprising an encircling band or bands located intermediate its ends and treated chemically or by constriction, or both, for the purpose of extinguishing the slow burning or smouldering of the cigarette when the smoking thereof is discontinued, whilst permitting the proper burning of the cigarette when smoked in the usual way.

However, this solution cannot be considered satisfactory, partly because of unreliability, partly because the chemically treated bands will cause formation of unaccept¬ able gases with bad or strange taste when exposed to the glow during or after smoking.

Cigarette filters containing a single or a plurality of collapsible capsule(s) or ampoule(s) filled with water or other liquids are known, e.g. from US patent specification no. 3,428,049 and DK patent specification no. 125,566. The water or liquid contained in these capsules or ampoules is released by applying a squeezing pressure to the outer wrapper of the filter, thereby breaking the collapsible capsule or ampoule. According to this part of the known art, the purpose of releasing the water or the liquid in the filter is to improve the effect of the filter and if desired to augment or supplement the flavour of the smoke.

The safe functioning of such filters is however endangered by untimely breaking of the collapsible capsules or ampoules, e.g. during the production of the filter; when the filters are arranged in the cigarettes; and during packaging and transport of the cigarettes from factory to user.

The object of the present invention is to provide a reliable self-extinguishing cigarette, as defined above, which does not exhibit any of the above mentioned draw¬ backs.

This is achieved according to the present invention by a self-extinguishing cigarette comprising a tubular outer wrapper surrounding a tobacco rod or column, which is characterized by comprising a non-collapsible elongated ampoule, which will break, soften, fuse or burn when exposed to heat, containing a non-inflammable liquid medium in a sufficient amount to extinguish the glow in the cigarette when liberated from the ampoule and arranged coaxially at the mouth end and within the body of the cigarette.

During smoking of the cigarette according to the present invention the glow will move down towards the ampoule, which will break, either directly by the action of the heat of the glow or indirectly by a pressure increase in the liquid medium, thus causing release of the liquid medium, preferably water or an aqueous solution, contained in the ampoule. The released water or liquid will then rapidly extinguish the glow, i.e. the cigarette, without any conscious action from the smoker being needed.

Since the non-collapsible construction of the ampoule ensures that it will not break when the cigarette is subjected to a normal squeezing pressure, i.e. a pressure less than what would destroy the cigarette in any case, there is no risk of untimely release of the water or liquid contained in the ampoule.

The ampoule is preferentially formed from a material, which will fuse or soften by the action of heat from the glow,and which does not produce noxious gases or any smell or taste when exposed to heat. Polyethylene and polypropylene are examples of such preferred materials. Preferably the ampoule has a length of about 10-25 mm, an external diameter of about 1.5 - 4 mm and an internal diameter of about 0.5 - 3.5 mm. Such ampoules can easily be manufactured by spot sealing a corresponding tube filled with water or liquid.

If desired, the water or the liquid may be kept at a moderate pressure within the ampoule.

The water or the liquid contained in the ampoule may contain additives, such as surfactants or other useful components, e.g. components augmenting or supplementing the flavour of the smoke, such as menthol or lemon oil.

Regardless of the composition and nature of the liquid in the ampoule, it should be present in a sufficient amount to extinguish the glow in the cigarette. In case of water less than 0.03 ml will generally suffice.

According to a preferred embodiment of the invention the ampoule is formed with a first end wall facing the glow and an opposite second end wall facing the mouth end of the cigarette, said first end wall being thinner than said second end wall.

The cigarette according to the present invention may also be provided with a filter element facing the tobacco rod or column. In this case the ampoule may be embedded partly in the filter element, partly in the tobacco rod, or it may be entirely embedded in the tobacco rod.

In the drawings

fig. 1 is a longitudinal cross-sectional view of one embodiment of the cigarette according to the invention, without filter tip; fig. 2 is a longitudinal cross-sectional view of another embodiment of the cigarette according to the invention, with filter tip; and

fig. 3 is a longitudinal cross-sectional view of a filter element containing an ampoule.

As shown in fig. 1 a cigarette 1 without filter comprises an outer wrapper 2 surrounding a tobacco rod or column 3 containing an ampoule 4 containing water 5 arranged at the mouth end of the cigarette.

The filter cigarette 1 shown in fig. 2 comprises an outer wrapper 2 surrounding a tobacco rod or column 3 facing a filter rod 6. In this case the ampoule 4 is embedded partly in the filter rod 6, partly in the tobacco rod 3.

If it is desired to provide a filter cigarette, which will extinguish when the glow is further away from the filter, the ampoule may be embedded totally in the tobacco rod.

Fig. 3 shows a filter element 7 which may be used in the manufacture of the cigarette shown in fig. 2. This filter element 7 comprises a filter rod 6 and an ampoule 4 partially embedded therein. The illustrated ampoule 4 is formed with a thin end wall 8 facing the glow and an opposite end wall 9 having normal thickness and facing the mouth end of the filter.

Claims

P A T E N T C L A I M S

1. A self-extinguishing cigarette comprising a tubular outer wrapper surrounding a tobacco rod or column, c h a r a c t e r i z e d by comprising a non-collapsible elongated ampoule, which will break, soften, fuse or burn when exposed to heat, containing a non-inflammable liquid medium in a sufficient amount to extinguish the glow in the cigarette when liberated from the ampoule and arranged coaxially at the mouth end and within the body of the cigarette.

2. A self-extinguishing cigarette according to claim

1, c h a r a c t e r i z e d in that the liquid medium is water or an aqueous solution.

3. A self-extinguishing cigarette according to claims 1 - 2, c h a r a c t e r i z e d in that the ampoule is shaped with a first end wall facing the glow and an opposite second end wall facing the mouth end of the cigarette, said first end wall being thinner than said second end wall.

4. A self-extinguishing cigarette according to claims 1 - 3, c h a r a c t e r i z e d in that the ampoule has a length of about 10 - 25 mm, an external diameter of about 1.5 - 4 mm, and an internal diameter of about 0.5 - 3.5 mm.

5. A self-extinguishing cigarette according to claims 1 - 4, c h a r a c t e r i z e d in that the ampoule is formed of a plastic material which will soften, fuse or burn when exposed to heat without liberating noxious or smelling gases.

6. A self-extinguishing cigarette according to claim 5, c h a r a c t e r i z e d in that said plastic material is polyethylene or polypropylene.

7. A self-extinguishing cigarette according to claims 1 - 6, c h a r a c t e r i z e d in that said cigarette is provided with a filter element facing the tobacco rod or column and that the ampoule is embedded partly in the filter element, partly in the tobacco rod.

8. A self-extinguishing cigarette according to claims 1 - 6, c h a r a c t e r i z e d in that said cigarette is provided with a filter element facing the tobacco rod or column and that the ampoule is entirely embedded in the tobacco rod.