WO2012013334A1

WO2012013334A1 - Cigarette paper having a high diffusion capacity during thermal decomposition

Info

Publication number: WO2012013334A1
Application number: PCT/EP2011/003743
Authority: WO
Inventors: Dietmar Volgger
Original assignee: Delfortgroup Ag
Priority date: 2010-07-30
Filing date: 2011-07-26
Publication date: 2012-02-02
Also published as: JP2013536326A; PL2597975T3; CN103002758A; BR112012033375B1; KR20130135835A; EP2597975B1; ES2663333T3; JP5897567B2; DE102010032814B4; MY161365A; DE102010032814A1; US20130139838A1; BR112012033375A2; EP2597975A1; KR101840071B1

Abstract

The invention relates to cigarette paper, which contains a water-soluble salt, preferably sodium bicarbonate, potassium bicarbonate or ammonium carbonate, as a result of which a high diffusion capacity during thermal decomposition, and thus a reduction in harmful carbon monoxide in the cigarette smoke, is achieved. The invention relates in particular to cigarette paper comprising at least one water-soluble salt which has lost more than 15% of its initial mass after heating to 230°C. The invention further relates to a cigarette produced from the cigarette paper, to a method for producing the cigarette paper and to the use of the water-soluble salt.

Description

Cigarette paper with high diffusion capacity during thermal decomposition

The present invention relates to a cigarette paper containing a water-soluble salt, preferably sodium hydrogencarbonate, potassium bicarbonate or ammonium carbonate, whereby a high diffusion capacity during thermal decomposition and thus a reduction of carbon monoxide in cigarette smoke is achieved.

BACKGROUND OF THE INVENTION

It is well known that cigarette smoke contains many harmful substances, including carbon monoxide. There is therefore a great interest in the industry to produce cigarettes whose smoke contains significantly less harmful substances. To reduce the amount of such substances, cigarettes are very often equipped with filters, typically of cellulose acetate. However, these filters are unable to reduce the level of carbon monoxide in the smoke of the cigarette because cellulose acetate can not absorb the carbon monoxide. Various proposals to incorporate catalysts into the filter to convert carbon monoxide into the less harmful carbon dioxide have hitherto been unsuccessful, partly for functional and economic reasons. It is also known to dilute the smoke produced in the cigarette, for example, by a stream of air flowing through the perforation of the tipping paper. This method has the advantage that it can reduce the content of carbon monoxide in the cigarette smoke, but has the disadvantage that also the taste of the cigarette determining substances are diluted and thus the taste impression of the cigarette and the customer acceptance are deteriorated.

It is also known that by increasing the gas diffusion through the cigarette paper, carbon monoxide in cigarette smoke can be selectively reduced. Various approaches to increase the diffusion constant of the cigarette paper, for example by selecting suitable particle size distributions of the fillers are already known in the art known. Although these approaches have shown initial success, there is still a lack of opportunity to increase the diffusion constant of the cigarette paper so significantly that a substantial reduction in carbon monoxide is achieved. High levels of carbon monoxide are also observed especially for the self-extinguishing cigarettes known from the prior art. In such cigarettes, fire retardant streaks are applied to the cigarette paper for self extinguishment in a standardized test (ASTM E2187-04). This test is part of legal regulations, such as in the US, Canada, Australia and Finland. The increased levels of carbon monoxide are due to the fact that the carbon monoxide can not diffuse through the fire-retardant strip from the cigarette. There is therefore an interest in industry to have cigarette papers available that compensate for this undesirable side effect. Typical cigarette papers are made from cellulose fibers derived from wood, flax or other materials. Mixtures of cellulose fibers of various origins are also used. Cigarette papers have a typical basis weight of 10 g / m ² to 60 g / m ² , with the range of 20 g / m ² to 35 g / m ^{2 being} generally preferred. Cigarette papers often also contain inorganic, mineral fillers which are added to the paper in a mass fraction of 10% to 40%. A frequently used filler is lime (calcium carbonate). However, other carbonates and oxides such as magnesium oxide and aluminum hydroxide are also used. The cigarette paper may also be provided with burn salts which increase or decrease the smoldering speed of the paper. Very often used are trisodium and tripotassium citrate and mixtures thereof, which are added to the paper to 0% to 5% of the paper pulp. However, the group of fire salts of industrial importance additionally comprises further citrates, malates, tartrates, acetates, nitrates, succinates, fumarates, gluconates, glycates, lactates, oxylates, salicylates, α-hydroxycaprylates and phosphates. The paper is impregnated, for example, in the size press with a solution or suspension of these Brandsalze, or the solution or suspension is applied in a film press on the surface of the paper. A typical feature of cigarette paper of great technical importance is its air permeability. It describes the permeability of the paper to an airflow caused by a pressure difference between the two sides of the paper. It therefore denotes the volume of air passing through the paper per unit time, per unit area and per pressure difference and therefore has the unit cm ³ / (min cm ² kPa). It is often referred to as CORESTA unit (CORESTA unit, CU), where 1 CU = 1 cm ³ / (min cm ² kPa). Typical cigarette papers have an air permeability between 10 CU and 300 CU, with the range 20 CU to 120 CU preferably being used. The air permeability can be determined, for example, according to ISO 2965.

Another important feature of the cigarette paper is its diffusion capacity. The diffusion capacity is a transfer coefficient and describes the permeability of the cigarette paper to a gas flow caused by a concentration difference. It therefore denotes the gas volume passing through the paper per unit of time, per unit area and per concentration difference and therefore has the unit cm ³ / (cm ² s) = cm / s. The diffusion capacity of a cigarette paper for C0 ₂ can be determined, for example, with the CO2 Diffusivity Meter from Sodim. Typical cigarette papers have a diffusion capacity between 0.1 cm / s and 3.5 cm / s at room temperature, with the range of 0.5 cm / s to 3.0 cm / s preferably occurring.

The diffusion capacity can be measured at room temperature or standard conditions, such as a temperature of 23 ° C and a relative humidity of 50%, after the paper has been conditioned accordingly. Alternatively, among other things, it is also possible to determine the diffusion capacity of the paper after the paper has been subjected to thermal stress, in particular by elevated temperatures.

Both the air permeability and the diffusion capacity are determined by the pore structure of the cigarette paper, so there is a relationship between these sizes. It proves technically difficult to adjust the diffusion capacity regardless of the air permeability of the paper in the papermaking process. In particular, the air permeability is in most cases the subject of the paper specification given by the manufacturers of cigarettes, so that, under this requirement, the diffusion capacity results practically from the papermaking process and only can be varied in a small area. Therefore, there is a particular interest in finding papers whose diffusion capacity increases only when needed, namely, just when the temperature of the paper is increased by the ember on the smoldering cigarette.

The substances in cigarette smoke are determined by a method in which the cigarette is smoked according to standardized specifications. Such a method is described for example in ISO 4387. In this case, the cigarette is first ignited at the beginning of the first train and then every minute a train at the mouth end of the cigarette with a duration of 2 seconds and a volume of 35 cm ^{3 performed} at a sinusoidal tensile profile on the cigarette. The trains are repeated as long as the cigarette until the cigarette falls below a certain predetermined in the standard length. The smoke flowing from the mouth end of the cigarette during traction is collected in a Cambridge filter ped and this filter is thereafter chemically analyzed for its content of various substances, for example nicotine. The gas phase flowing from the mouth end of the cigarette during the trains through the Cambridge Filter Päd is collected and also chemically analyzed, for example to determine the content of carbon monoxide in the cigarette smoke. During standardized smoking, the cigarette is therefore in two fluidically different states. During the draw, there is a significant pressure difference, typically in the range of 200 Pa to 1500 Pa, between the tobacco-facing inside of the cigarette paper and the outside of the cigarette paper. By this pressure difference, air flows through the cigarette paper in the tobacco part of the cigarette and dilutes the resulting smoke during the move. During this phase, which lasts 2 seconds per draw, the extent of dilution is determined by the air permeability of the paper.

In contrast, during the period between trains, the cigarette will glow without any appreciable pressure difference between the inside of the tobacco part of the cigarette and the environment, so that the gas transport is determined by the gas concentration difference between the tobacco part and the environment. It is also carbon monoxide through the cigarette paper from the tobacco part and in particular from the region of the cone of gluten in the Ambient air diffuse. In this phase, which lasts 58 seconds per turn, the diffusion capacity for the reduction of carbon monoxide is the relevant parameter.

In order to reduce the content of carbon monoxide in the smoke, it is therefore important that the diffusion capacity of the cigarette paper is high and that it is high, in particular in the area of the cone of embers, since at this point the carbon monoxide is formed. It is thus particularly advantageous if the diffusion capacity is high or rises rapidly as soon as the cigarette paper is exposed to elevated temperatures due to the approach of the cone. Smoking off a cigarette reveals quite clearly a so-called "char line" in the area of the glow cone, which separates the already almost completely thermally destroyed cigarette paper from the still largely intact cigarette paper Measurements from the prior art show that the so-called "char line" has a temperature of about 450 ° C. Accordingly, it is therefore important that the diffusion capacity of the cigarette paper already at temperatures substantially below 450 ° C, is high or rises sharply.

An object of the invention is to provide a cigarette paper having an increased diffusion capacity, which enables reduction of carbon monoxide in the cigarette smoke.

SUMMARY OF THE INVENTION

The invention achieves this object by impregnating or coating the cigarette paper with one or more water-soluble salts which, at relatively low temperatures, i. significantly less than 450 ° C, disintegrate and thereby loosen up the pore structure of the paper on a smoldering cigarette made thereof, so that a significantly better diffusion of carbon monoxide from the cigarette is allowed.

In particular, the object of the invention is achieved by a cigarette paper comprising at least one water-soluble salt which has lost more than 15% of its initial mass after heating to 230 ° C, the heating, starting from a starting temperature of 30 ° C, with a heating rate of 5 ° C / min under a stream of nitrogen of 25 ml / min. In one embodiment, the water-soluble salt loses more than 20%, preferably more than 25%, more preferably more than 30%, and most preferably more than 35% of its starting material. In one embodiment, the water-soluble salt is an inorganic salt or a mixture of inorganic salts.

In one embodiment, the water-soluble salt is a hydrogencarbonate, preferably an alkali metal bicarbonate or an ammonium bicarbonate, or a carbonate, preferably an ammonium carbonate. A mixture of these salts is also contemplated.

In a preferred embodiment, the water-soluble salt or the alkali metal bicarbonate is a sodium or potassium bicarbonate. A mixture of the two salts is also contemplated.

In a particularly preferred embodiment, the water-soluble salt or the alkali metal bicarbonate is a potassium bicarbonate. In one embodiment, the content of the water-soluble salt is 0.1% to 10%, preferably 1% to 6%, particularly preferably 3% to 6% of the paper pulp. These levels can also be achieved by a mixture of different water-soluble salts.

In a preferred embodiment, the water-soluble salt is sodium bicarbonate with a content of at least 4%, preferably 4% to 10%, particularly preferably 4% to 6% of the paper pulp.

In an alternative preferred embodiment, the water-soluble salt is potassium bicarbonate of at least 3%, preferably 3% to 10%, more preferably 3% to 6% of the paper pulp.

In a further alternative preferred embodiment, the water-soluble salt is ammonium carbonate with at least 4%, preferably 4% to 10%, more preferably 4% to 6% of the paper pulp. In one embodiment, the water-soluble salt is contained in partial areas of the cigarette paper, preferably in discrete strip-shaped partial areas. In a preferred embodiment, the subregions are designed such that they form one or more bands in the circumferential direction of a tobacco rod on a cigarette made from the cigarette paper.

This may be advantageous, for example, if the cigarette paper, as known in the art, is already provided with diffusion-reducing, fire-retardant stripes in order to achieve self-extinguishment of a cigarette produced therefrom in a standardized test (ASTM E2187-04). Typically, these fire retardant strips are arranged to form ribbons on the cigarette circumferentially. Such cigarettes have increased levels of carbon monoxide because less carbon monoxide can diffuse from the cigarette through the fire retardant strips. To compensate for this effect, it may be useful to apply to the still untreated areas of the cigarette paper, so the areas away from the fire-retardant strip, the salts of the invention to achieve higher diffusion capacities during thermal decomposition of the cigarette paper in these areas to compensate.

In a particularly preferred embodiment, the subregions are separated from fire-retardant areas, preferably fire-retardant strips. The term "separated" is intended to mean that the portions are defined by the fire retardant areas, but also takes into account a certain overlap, which may be caused, for example, manufacturing techniques.

In one embodiment, the cigarette paper is impregnated (soaked) with the water-soluble salt. In an alternative embodiment, the cigarette paper is coated with the water-soluble salt on one or both sides.

Furthermore, the object of the invention is achieved by a cigarette paper comprising at least one water-soluble salt, wherein the at least one water-soluble salt Hydrogen carbonate, preferably an alkali metal bicarbonate or an ammonium bicarbonate, or a carbonate, preferably an ammonium carbonate. Mixtures of these salts are also contemplated. In a preferred embodiment, the alkali metal bicarbonate is a sodium or potassium bicarbonate. Mixtures of the two salts are also contemplated.

In a particularly preferred embodiment, the alkali metal bicarbonate is a potassium bicarbonate.

In one embodiment, the content of the above-defined water-soluble salt is 0.1% to 10%, preferably 1% to 6%, particularly preferably 3% to 6% of the paper pulp. In a preferred embodiment, the above-defined water-soluble salt is a Natnumhydrogencarbonat with a content of at least 4%, preferably 4% to 10%, particularly preferably 4% to 6% of the paper pulp.

In an alternative preferred embodiment, the above-defined water-soluble salt is a potassium hydrogencarbonate having at least 3%, preferably 3% to 10%, more preferably 3% to 6% of the paper pulp.

In a further alternative preferred embodiment, the above-defined water-soluble salt is an ammonium carbonate having at least 4%, preferably 4% to 10%, more preferably 4% to 6% of the paper pulp.

In one embodiment, the above-defined water-soluble salt is contained in discrete portions of the cigarette paper, preferably in strip-shaped portions. In a preferred embodiment, the subregions with the above-defined water-soluble salt are designed such that they form one or more bands in the circumferential direction of a tobacco rod on a cigarette made from the cigarette paper. In a particularly preferred embodiment, the subregions are separated from fire-retardant areas.

In one embodiment, the cigarette paper is impregnated (soaked) with the above-defined water-soluble salt.

In an alternative embodiment, the cigarette paper is coated with the water-soluble salt defined above on one or both sides. The object of the invention is further achieved by a cigarette which comprises a cigarette paper according to the invention.

The cigarette can be produced on conventional cigarette machines from the cigarette paper with the aid of further, sometimes optional components such as tobacco, tipping paper, filters, filter wrap paper and glue.

The object of the invention is further achieved by a method for producing a cigarette paper according to the invention, the method comprising the following steps:

(1) providing a cigarette paper or a fiber-filler suspension having less than 50%, preferably less than 30% water content, based on the total mass of the paper or the total mass of the fiber-filler suspension;

(2) applying an aqueous solution having at least one water-soluble salt, wherein the content of the water-soluble salt in the solution is 0.2% to 20%, preferably 2% to 15%, based on the mass of the solution.

In one embodiment of the method, the water-soluble salt is an inorganic salt. Mixtures of inorganic salts in the aqueous solution are also contemplated.

In one embodiment of the method, the water-soluble salt in the aqueous solution is a bicarbonate, preferably an alkali metal bicarbonate or an ammonium bicarbonate, or a carbonate, preferably an ammonium carbonate. Mixtures of these salts in the aqueous solution are also contemplated. In a preferred embodiment of the process, the water-soluble salt or the alkali metal bicarbonate is a sodium or potassium hydrogencarbonate. Mixtures of the two salts in the aqueous solution are also contemplated.

In a particularly preferred embodiment, the water-soluble salt or the alkali metal bicarbonate is a potassium bicarbonate.

In one embodiment, the content of the at least one water-soluble salt is 0.1% to 10%, preferably 1% to 6%, particularly preferably 3% to 6%, of the paper pulp of the cigarette paper produced by the process.

In one embodiment, in step (2) of the method, the water-soluble salt is applied in partial areas of the cigarette paper, preferably in discrete strip-shaped partial areas.

In a preferred embodiment, the subregions are designed such that they form one or more bands in the circumferential direction of a tobacco rod on a cigarette made from the cigarette paper.

In a particularly preferred embodiment, the subregions are separated from fire-retardant areas.

In one embodiment, in step (2) of the method, the aqueous solution is applied using a size press or a film press.

The application of the aqueous solution in the size press or film press of a paper machine takes place over the whole area on one or both sides of the paper. In this case, the paper in the paper machine is substantially impregnated with the solution.

In an alternative embodiment, in step (2) of the method, the application of the aqueous solution is carried out using a printing or spraying technique. The application of the aqueous solution by means of a printing process or by spraying in or after the paper machine offers the possibility of applying the solution more superficially and only on one side of the paper. This can be advantageous if the solution alters the optical properties of the paper. Then preferably the solution is applied to the later side of the tobacco facing the paper.

Other methods of applying an aqueous solution to paper are also contemplated. However, it is important that the solution is applied at a time during or after the paper production, to which the cigarette paper is already able to take up the solution and to fix the water-soluble salt largely in the fiber structure. This will be the case if the paper or the fiber-filler suspension passing through the paper machine has a water content of less than 50%, based on the total paper mass, preferably less than 30%, based on the entire paper pulp, which is conventional Paper machines is mostly reached when the paper leaves the press section. For example, it is not advantageous to mix water-soluble carbonates or bicarbonates, such as a filler of the fiber-filler suspension, before this suspension reaches the paper machine, since the carbonates or bicarbonates in solution in the dewatering process in the wire section of the paper machine are largely lost again in the dewatering process ,

The object of the invention is further achieved by the use of at least one water-soluble salt, preferably an inorganic salt, for increasing the diffusion capacity of a cigarette paper or portions of a cigarette paper during thermal decomposition by more than 0.9 cm / s and / or more as 50%, based on an initial value of the diffusion capacity at 23 ° C before the thermal decomposition.

In one embodiment of the use, the water-soluble salt is a hydrogencarbonate, preferably an alkali metal bicarbonate or an ammonium bicarbonate, or a carbonate, preferably an ammonium carbonate.

In one embodiment of the use, the water-soluble salt is an alkali metal bicarbonate. In a preferred embodiment of the use, the alkali metal bicarbonate is a potassium bicarbonate.

The features disclosed herein and the claims of the invention may be essential both individually and in any combination for the realization of the invention in its various embodiments.

The invention is based on the surprising finding that a cigarette paper with an increased diffusion capacity can be achieved by impregnating or coating the paper with certain salts, shown here with sodium bicarbonate, potassium bicarbonate and ammonium carbonate, which are already at comparatively low temperatures, ie significantly lower 450 ° C, decay and thus open the pore structure of the cigarette paper. It has been shown that the increase in the diffusion capacity of the cigarette paper during the thermal decomposition can be partially increased by more than double. Such an increase in the diffusion capacity increase can significantly contribute to the reduction of harmful carbon monoxide in the smoke of cigarettes made from these papers.

DETAILED DESCRIPTION OF THE INVENTION

The invention will be described in more detail below with reference to the examples and the attached drawing.

Figure 1 shows the mass loss of water-soluble salts during heating in the thermogravimetric analysis. Shown is the loss of mass in% of the starting mass as a function of the temperature. The heating to a temperature of up to 600 ° C, wherein the starting temperature was 30 ° C, was carried out at 5 ° C / min under nitrogen flow at 25 ml / min. TKZ, tripotassium citrate; TNZ, trisodium citrate.

EXAMPLES

Example 1: Preparation of cigarette paper with sodium bicarbonate,

Potassium bicarbonate or ammonium carbonate

A cigarette paper made of wood pulp, wherein 32% of the paper pulp consisted of lime as filler, and with a basis weight of 25 g / m ² , an air permeability of 30 CU and a diffusion capacity of 1.75 cm s was chosen for the experiments. This is a common cigarette paper, so that comparable results can be expected with other cigarette papers and in principle there are no restrictions on the selection of the cigarette paper, for example in terms of air permeability, diffusion capacity, fiber and filler composition or basis weight.

This cigarette paper was impregnated with aqueous solutions of sodium bicarbonate (NaHC0 ₃ ), potassium bicarbonate (KHCO ₃ ) or ammonium carbonate ((NH ₄ ) ₂ C0 ₃ ) in various concentrations in the size press.

For comparison served the same cigarette paper, which with an aqueous solution of trisodium citrate (TNZ) or a 50:50 mixture, based on the mass of trisodium citrate and tripotassium citrate (TNZ / TKZ), ie conventional Brandsalzen, in different concentrations also in the size press was impregnated. EXAMPLE 2: Measurement of the diffusion capacity of the produced cigarette paper

The diffusion capacity of the cigarette papers produced in Example 1 was determined using a CO2 Dij usivity meter Sodim.

The diffusion capacity of the papers at 23 ° C and 50% humidity was uniformly about 1.75 cm / s. After being exposed to a temperature of 230 ° C for 30 minutes, the papers were conditioned to 23 ° C and 50% RH and the diffusion capacity was measured. The absolute measurements are given in Table 1.

Table 1: Diffusion capacity in cm / s after heating (230 ° C, 30 min)

* corresponds to% by weight Table 1 shows that the diffusion capacity of papers with sodium bicarbonate, potassium bicarbonate or ammonium carbonate at any given content in the pulp is higher than that of papers with trisodium citrate or trisodium / tripotassium citrate. The highest diffusion capacity measured with citrate is 2.616 cm / s at 7% trisodium / tripotassium citrate. Higher values than 2.616 cm / s are achieved with sodium bicarbonate and ammonium carbonate from a content of 4% and with potassium bicarbonate even from a content of 3%. A diffusion capacity of 2.7 cm / s and more is achieved only with sodium bicarbonate (> 6%), potassium bicarbonate (> 4%) or ammonium carbonate (> 5%), but not with the citrates. The increase of the diffusion capacity in cm / s from the initial value at room temperature of 1.75 cm / s and the percentage increase relative to this initial value are given in Table 2. Table 2: Change in the diffusion capacity in cm / s and in% after heating (230 ° C,

30 min).

* corresponds to wt .-% It is clearly seen in Table 2 that the use of sodium or potassium bicarbonate or by ammonium carbonate, the increase in the diffusion capacity of the cigarette paper during thermal decomposition can be partially increased by more than twice compared to citrates as conventional Brandsalzen.

The examples further show that an increase in the diffusion capacity of more than 0.9 cm / s, starting from the initial value at 23 ° C, in this case of 1.75 cm / s, or a percentage increase in the diffusion capacity by more than 50%, also based on the initial value at 23 ° C, can not be achieved with citrates as conventional Brandsalzen, but with the inorganic salts used. For this purpose, at least 4% sodium bicarbonate or at least 3% potassium hydrogen carbonate or at least 4% ammonium carbonate must be used. It can also be seen from the examples that an increase in the content of sodium bicarbonate beyond 6% achieves no further significant improvement, so that a content of at most 6% based on the paper pulp is to be preferred. In the case of potassium bicarbonate, on the other hand, a further increase in the content beyond 6% still results in a noticeable improvement, so that an upper limit for the sensible use of potassium bicarbonate can not be determined on the basis of the experiments, but the content is rather due to the taste impression of a To limit such cigarette made paper with about 10%. In the case of ammonium carbonate, the improvement that can be achieved seems to be getting smaller and smaller with a content exceeding 6%, but it does not come to a standstill up to a content of 8%, so that even here a reasonable upper limit of about 10% can be drawn. On the whole, the potassium hydrogencarbonate proves to be superior to the sodium hydrogencarbonate or the ammonium carbonate for the intended effect, so that it can be used with particular preference.

The reason for the observed effect is probably that sodium and potassium bicarbonate already decompose at lower temperatures than conventional Brandsalze, namely from about 50 ° C. Even ammonium bicarbonate and ammonium carbonate decompose already from a temperature of 60 ° C and thus at much lower temperatures than trisodium or tripotassium citrate, both of which decompose only from 150 ° C. An analysis by thermogravimetry of the sodium and potassium bicarbonate used in Table 1 for application to the paper, these substances being heated from 30 ° C to 600 ° C under a nitrogen stream of 25 ml / min at a rate of 5 ° C / min , points out that the rapid mass loss at relatively low temperatures is responsible for increasing the diffusion capacity. The results are shown in Figure 1. It can be seen that on reaching 230 ° C the mass loss in the case of sodium bicarbonate is about 35% of the starting mass and in the case of potassium bicarbonate about 30% of the starting mass. The figure further indicates that sodium and potassium bicarbonates not only result in an absolute increase in the diffusion capacity as shown in Table 1, but that it is also higher in the range of about 130 ° C to 230 ° C than in conventional brine salts. It can therefore be assumed that the observed effect may be expected if, under the conditions of this analysis method, the selected inorganic salt at 230 ° C. is at least about 30% to 35%, presumably already at lower proportions, eg from 15% or 25%, lost its initial mass.

Claims

claims

A cigarette paper comprising at least one water-soluble salt, characterized in that the water-soluble salt is a salt which, after heating to 230 ° C, has lost more than 15%, preferably more than 25%, of its initial mass when heating, starting from a starting temperature of 30 ° C, with a heating rate of 5 ° C / min under a nitrogen flow of 25 ml / min.

2. The cigarette paper according to claim 1, wherein the water-soluble salt is a hydrogencarbonate, preferably an alkali metal bicarbonate or an ammonium bicarbonate, or an ammonium carbonate.

3. cigarette paper comprising at least one water-soluble salt, characterized in that the water-soluble salt is a hydrogencarbonate, preferably an alkali metal bicarbonate or an ammonium bicarbonate, or an ammonium carbonate.

A cigarette paper according to claim 2 or 3, wherein the alkali metal hydrogencarbonate is a sodium or potassium hydrogencarbonate.

5. A cigarette paper according to any one of the preceding claims, wherein the content of the water-soluble salt is 0.1% to 10%, preferably 1% to 6%, particularly preferably 3% to 6% of the paper pulp.

6. The cigarette paper according to one of the preceding claims, wherein the water-soluble salt is contained in discrete subregions, preferably in strip-shaped subregions.

7. The cigarette paper according to claim 6, wherein the portions are configured such that they form one or more bands in the circumferential direction of a tobacco rod on a cigarette made from the cigarette paper.

8. A cigarette paper according to any one of claims 1 to 7, wherein the cigarette paper is impregnated with the at least one water-soluble salt.

9. A cigarette paper according to any one of claims 1 to 7, wherein the cigarette paper is coated with the at least one water-soluble salt on one side or on both sides.

A cigarette comprising a cigarette paper according to any one of claims 1 to 9.

11. A method for producing a cigarette paper according to any one of claims 1 to 9, or for the production of a cigarette according to claim 10, comprising the following steps:

(2) applying an aqueous solution having at least one water-soluble salt to the cigarette paper or fiber-filler suspension passing through a paper machine, the content of the water-soluble salt in the solution being 0.2% to 20%, preferably 2% to 15%, based on the mass of the solution.

12. The method of claim 11, wherein the water-soluble salt is a bicarbonate, preferably an alkali metal bicarbonate or an ammonium bicarbonate, or a carbonate, preferably an ammonium carbonate.

13. The method of claim 12, wherein the alkali metal bicarbonate is a sodium or potassium bicarbonate.

14. The method according to any one of claims 11 to 13, wherein the application of the aqueous solution is carried out using a size press or a film press.

15. The method according to any one of claims 11 to 13, wherein the application of the aqueous solution is carried out using a printing or spraying technique.

16. Use of at least one water-soluble salt to increase the diffusion capacity of a cigarette paper, or portions of a cigarette paper, during thermal decomposition by more than 0.9 cm / s and / or by more than 50%, based on the initial value of the diffusion capacity at 23 ° C before thermal decomposition.

17. Use according to claim 16, wherein the water-soluble salt is a hydrogencarbonate, preferably an alkali metal bicarbonate or an ammonium bicarbonate, or a carbonate, preferably an ammonium carbonate.

18. Use according to claim 17, wherein the alkali metal bicarbonate is a sodium or potassium bicarbonate.