ES2717664T3 - Cigarette and cigarette paper that reduce the visible amount of secondary smoke and the amount of carbon monoxide in the primary smoke - Google Patents

Description

DESCRIPTION

Cigarette and cigarette paper that reduce the visible amount of secondary smoke and the amount of carbon monoxide in the primary smoke

Field of the invention

This invention relates to a cigarette paper and a cigarette, and more specifically refers to a cigarette paper and a cigarette that reduce a visible amount of secondary smoke and an amount of carbon monoxide in the primary smoke.

Background of the technique

Recently, a cigarette (secondary low smoke cigarette) has been developed that generates a small amount of secondary smoke. The fact that said cigarette actually generates a small amount of secondary smoke is generally determined by a so-called fishtail method (described in Health Canada Test Method T-212). In this fish tail method, the total amount of particulate material in the secondary smoke is measured, and the total amount of particulate material is considered as a secondary smoke quantity.

In order to provide a cigarette that generates a small amount of secondary smoke, a charge which is a compound having a combustion inhibiting effect is added to the cigarette paper. For example, Patent Document 1 discloses that magnesium hydroxide gel is added, and Patent Document 2 discloses that a filler having a high specific surface area formed by calcium carbonate and so on is added.

Meanwhile, Patent Document 3 discloses a cigarette paper which can reduce the amount of secondary smoke according to visual observation (also called the amount of secondary smoke visible in this specification) instead of the amount of secondary smoke according to the method of fish tail. This cigarette paper contains calcium carbonate in an amount of 30 g / m2 or more and a combustion regulating agent such as potassium citrate in an amount of 3% by weight or more.

Appointment list

Patent bibliography

Patent Bibliography 1: Japanese Patent Application Publication No. KOKOKU 63-37621 Patent Bibliography 2: Japanese Patent No. 2730894

Patent Bibliography 3: Japanese Patent No. 3897700

US5065777A discloses a cigarette paper with a grammage of 40 to 55 g / m2 or more and a calcium carbonate content of 18 g / m2 or more.

Compendium of the invention

Technical problem

Although the cigarette with secondary low smoke according to the prior art significantly reduces the amount of secondary smoke, there is a tendency to increase the amount of carbon monoxide in the primary smoke. Accordingly, an object of the invention is to provide a cigarette paper that can reduce a visible amount of secondary smoke and at the same time reduce an amount of carbon monoxide in a primary smoke.

Solution to the problem

In order to solve the above problem, this invention provides a cigarette paper having a grammage of 40 to 55 g / m2 and containing calcium carbonate in an amount of 18 g / m2 or more, characterized in that a primary particle of calcium carbonate has a column shape or needle shape, and the primary calcium carbonate particle has an average aspect ratio of not less than 4 and less than 10 and has an average length (L) of 0.1 at 1.5 pm, the secondary calcium carbonate particle is in the shape of a milling cutter.

This invention further provides a cigarette that includes a cigarette rod that includes tobacco strips wrapped in the shape of a rod with said cigarette paper, and a filter connected coaxially to one end of the cigarette rod by means of a paper nozzle.

Advantageous effects of the invention

A cigarette paper and a cigarette according to this invention reduce the amount of secondary smoke generated and the amount of carbon monoxide in the primary smoke.

Brief description of the figures

FIG. 1 is a view schematically showing a typical form of the primary particles of calcium carbonate.

FIG. 2 is a view schematically showing an example of secondary particles having a strawberry shape.

FIG. 3 is a schematic perspective view showing an apparatus that measures the amount of secondary smoke visible from a smoking article according to the present invention.

FIG. 4 is a block diagram schematically showing a composition of the apparatus that measures the amount of secondary smoke visible from the smoking article according to the present invention.

FIG. 5 is a schematic diagram showing an apparatus for evaluating the amount of visible secondary smoke that can be used in sensory evaluation.

Description of the realizations

In the following, the present invention will be explained in detail.

The cigarette paper according to this invention has a grammage of 40 to 55 g / m2 and contains calcium carbonate in an amount of 18 g / m2 or more.

The pulp fiber used in the cigarette paper according to this invention may be constituted by flax pulp fiber used in a typical cigarette paper, wood pulp fiber (hardwood pulp, softwood pulp), etc.

The cigarette paper according to this invention is prepared by mixing 18 g / m2 or more of calcium carbonate with the pulp fiber. Calcium carbonate is contained in the form of particles, and although the diameter of the particle can be suitably selected in terms of cost and ease of papermaking, the diameter of the particle is preferably 0.02 to 10 μm. The content of calcium carbonate is preferably 29 g / m2 or less. The calcium carbonate content more preferably is 20 to 25 g / m2. In this specification, the content of calcium carbonate means the amount of calcium carbonate contained in a cigarette paper after manufacture. The amount of calcium carbonate in the cigarette paper can be obtained by extracting and then quantifying the calcium ions as described in an example which will be described later.

The calcium carbonate used in this invention is a synthetic calcium carbonate synthesized by chemical reaction, and the primary particles of the synthetic calcium carbonate all have substantially the same shape and size and are homogeneous. In this specification, the term "primary particles" refers to fundamental particles that constitute a powder immediately after synthesis by chemical reaction, and the term "secondary particles" refers to an aggregate formed by the agglomeration of a large amount of primary particles.

The shape of the primary calcium carbonate particles to be used is not particularly limited, and primary particles having any shape from a spindle form, a cubic shape, a column shape and a needle shape can be used. . However, when calcium carbonate is used in which the primary particles have a column shape or a needle shape, the amount of carbon monoxide in the primary smoke is significantly reduced compared to the case where carbonate is used of calcium that has another form.

FIG 1 shows a typical form of a primary calcium carbonate particle. The primary particles shown in FIG. 1 have a shape that extends in one direction. The direction of particle extension is the longitudinal direction, and the maximum value in the longitudinal direction is referred to as the length (L). The direction perpendicular to the longitudinal direction is the lateral direction, and the maximum value in the lateral direction is referred to as the width (W). The ratio of the length (L) to the width (W) of the primary particle is referred to as an aspect ratio. The ratio (aspect ratio) of the length (L) with respect to the width (W) of the primary particle in the form of a column or in the shape of a needle preferably is not less than 4 and less than 10. Both the particle in the form of Column as the needle-shaped particle refers to particles that have an aspect ratio of not less than 4 (FIG 1). The column shape and the needle shape can be distinguished by determining whether or not the primary particle observed with an electron microscope has a pointed shape. Specifically, the column shape does not have a pointed shape (FIGS.

1 (d) and (f)), and the needle shape has a pointed shape (FIGS.1 (a) and (c)). The needle shape can have a pointy shape at both ends in the direction of particle extension or may have the pointed shape at one end. The column shape not only includes a circular cylindrical shape but also a truncated conical shape.

For example, the width (W) and length (L) of the primary particle can be measured using a scanning electron microscope.

The primary calcium carbonate particle used in this invention has a column shape or a needle shape, and, at the same time, the shape of the secondary particle formed by agglomeration in a typical paper manufacturing process has a strawberry shape . The strawberry shape represents a form of agglomeration in which tens to thousands of primary particles having a column or needle shape are entangled three-dimensionally. As a specific example of the strawberry shape, there are aspects that are shown in Japanese Patent Application Ko KAI Publication Nos. 55-40849 and 59-94700. FIG. 2 schematically shows an example of the shape of a milling cutter. The strawberry shape has a central nuclear body at its center, a large number of primary particles can protrude from the central nuclear body, and the strawberry shape may not have the central nuclear body at its center. For example, calcium carbonate in which the secondary particles have a strawberry shape is commercially available as Cal-light-SA (Shiraishi Kogyo Kaisha, Ltd.) and strawberry-shaped calcium carbonate (Newlime Co., Ltd. ).

The calcium carbonate in which the secondary particles are in the strawberry form and wherein the calcium carbonate is in the form of the primary particle having a column or needle shape, may be contained in the pulp fiber; said calcium carbonate in the form of the secondary particle (which is strawberry-shaped) may be contained in the pulp fiber, or the calcium carbonate as a mixture having the forms of the primary particle and the secondary particle, may be content in pulp fiber. In each case, calcium carbonate is shaped like a strawberry on cigarette paper.

In this invention, the primary particles of calcium carbonate have a column or needle shape. The average aspect ratio of the primary particles is within the range of not less than 4 and less than 10, and an average length (L) of the primary particles is 0.1 to 1.5 pm. It is even more preferable that the density of the cigarette paper obtained is 0.4 to 1.0 g / cm3.

To obtain the average aspect ratio, representative plural particles are selected (at least 50 and, for example, 50 to 200), the aspect ratio is obtained by measuring the width (W) and the length (L) of the particles primary for each particle, and you get a mean value of the aspect ratio, so you can get the average aspect ratio. To obtain the average length (L), representative plural particles are selected (at least 50 and, for example, from 50 to 200), the length (L) of each particle is measured and an average value of the length is obtained (L ), so that the average length (L) can be obtained.

The cigarette paper according to this invention has a grammage of 40 to 55 g / m2. It is more preferable that the grammage of the cigarette paper be 42 to 50 g / m2.

The cigarette paper according to this invention can contain a combustion regulating agent. As the combustion regulating agent, an alkali metal citrate is preferably used, and potassium citrate and sodium citrate are particularly preferred, and these combustion regulating agents can be used alone or can be used in combination . The cigarette paper preferably contains the combustion regulating agent in an amount of 1.0 to 5.0% by weight, and more preferably 1.5 to 4.0% by weight. The cigarette paper according to this invention reduces the amount of secondary smoke visible from a cigarette and, at the same time, can reduce the amount of carbon monoxide in the primary smoke compared to a conventional cigarette paper.

The cigarette paper according to this invention can be used as a cigarette paper, of a cigarette with a filter. Specifically, according to one aspect of this invention, there is provided a cigarette that includes a cigarette rod that includes tobacco strips wrapped in a rod shape with the cigarette paper of the invention and a filter coaxially connected to one end of the cigarette rod. using a nozzle paper.

The amount of carbon monoxide in the primary smoke can be measured as the amount of carbon monoxide per puff that is obtained by dividing the total amount per cigarette under specific conditions for smoking cigarettes (Health Canada Test Method: 55 ml / 2 s) by the total number of puffs.

Although the amount of visible secondary smoke can be measured by sensory evaluation, the amount of visible secondary smoke can be measured simply by using a visible secondary smoke quantity measuring apparatus described in Japanese Patent No. 3683792 (or in the US Bibliography). Patent 3). The apparatus for measuring the amount of visible secondary smoke will be described below using FIGS. 3 and 4 (reproductions of FIGS.1 and 2 of Japanese Patent No. 3683792) for confirmation.

FIG. 3 is a schematic perspective view showing the apparatus for measuring the amount of visible secondary smoke described in Japanese Patent No. 3683792. FIG. 4 is a block diagram that shows schematically a configuration of the apparatus for measuring the amount of visible secondary smoke.

As it is shown in FIGS. 3 and 4, there is provided a device for measuring the amount of visible secondary smoke 10 with a spontaneous combustion chamber 11 for a smoking article, a visible light emitting unit 12 used to apply a predetermined visible light beam to secondary smoke , generated by the spontaneous combustion of the smoking article and which naturally rises (rises) in the spontaneous combustion chamber 1, in a direction substantially perpendicular to a direction of a secondary smoke flow, and an intensity detecting unit. the scattered light 14 used to detect, as an index of the visible secondary smoke quantity, the intensity of the scattered light, dispersed by the secondary smoke in a direction substantially perpendicular to the direction of the visible light beam.

The spontaneous combustion chamber 11, for example, is formed by a material for protection against light and is constituted by a rectangular parallelepiped tubular body elongated in a longitudinal direction prescribed by four side walls 11a to 11d for example. The side wall 11a has in its lower part an opening 111 for insertion of the smoking article through which a smoking article SA, such as a lit cigarette, is fitted in the spontaneous combustion chamber 11. The four side walls 11a at 11d indicating the spontaneous combustion chamber 11, respectively have ventilation windows 112 to 115, such as the mesh windows at their lowermost terminal parts, so that the air required for the spontaneous combustion of the smoking article SA can be supplied in the spontaneous combustion chamber 11. It is preferable that the position of the opening 111 for insertion of a smoking article be established in a position where the secondary smoke SSS of the smoking article SA placed in the spontaneous combustion chamber 11 a through the insertion opening 111 pass through the ventilation windows 112 to 115, it is not affected by the disturbance ion of the outside air that enters the spontaneous combustion chamber 11, and is at a distance from the smoking article SA to the upper end of the spontaneous combustion chamber 11 that is sufficient so that the secondary SSS smoke does not sway substantially.

The glass beads (not shown) are loaded in a lower space of the spontaneous combustion chamber 11 surrounded by the ventilation windows 112 to 115, so that the flow of the secondary smoke SSS that rises in the chamber of spontaneous combustion 11 due to spontaneous combustion of the smoking article, whereby a rectifying layer of the air flow can be formed. The upper end of the spontaneous combustion chamber 11 is open. An exhaust hood 15 may be installed at the open end in order to empty the spontaneous combustion chamber 11. It is required that the spontaneous combustion chamber 11 be emptied to avoid a substantial influence on the spontaneous combustion of the smoking article SA. In the case of emptying, in order to avoid disturbance of the secondary smoke flow SSS that rises naturally in the spontaneous combustion chamber 11 due to the spontaneous combustion of the smoking article, it is preferable that a rectification filter 16 be joined through an upper open end of the spontaneous combustion chamber 11.

The exhaust hood 15 has an exhaust duct 151 at its upper part, and the exhaust duct 151 is connected to an exhaust system (not shown).

The visible light emitting unit 12 is disposed outside the spontaneous combustion chamber 11. In an example shown in FIG. 3, the visible light emitting unit 12 is disposed outside the side wall 11b facing the side wall 11a of the spontaneous combustion chamber 11 into which the smoking article SA is inserted. A visible light transmission window 116 is arranged in a part of the side wall 11b facing the visible light emitting unit 12. The visible light emitting unit 12 has a visible light source (not shown) and applies a light beam to the visible light emitting unit 12. VLB visible light to the secondary smoke SSS, generated by the spontaneous combustion of the smoking article SA and which rises naturally in the spontaneous combustion chamber 11, in the direction substantially perpendicular to the flow direction of the secondary smoke SSS. A visible light source is not limited, especially while emitting visible light, and although, for example, a visible light laser, a visible light emitting diode, a halogen lamp, etc. can be used in a representative manner an A light source specified by the international lighting commission is used.

The visible light beam (visible light flux) VLB emitted from the visible light emitting unit 12 has a substantial cross-sectional area in which the visible light can be applied to the secondary SSS smoke that rises naturally in the combustion chamber spontaneous 11 while, even if the SSS secondary smoke sways a little, the roll is sufficiently covered. For example, the visible light beam VLB has a width w (FIG 4) in the direction perpendicular to the direction of irradiation and, at the same time, has a rectangular cross section having a height in a direction substantially perpendicular to the direction of irradiation of the visible light beam VLB so that it corresponds to a visual field in the sensory evaluation in consideration of a human visual field. It is preferable that the width w be at least equal to the width of the secondary smoke roll ^s S ^s in the direction perpendicular to the direction of irradiation of the visible light beam. The cross-sectional area of the visible light beam is not limited to a rectangular shape and may be an elliptical shape, circular shape, etc. In such a shaping of the visible light beam, a mask having an opening corresponding to the cross-sectional area of the visible light beam can be used, or for example, a lens system consisting of a combination of a convex lens and a concave lens can be used, and the configuration itself can be realized by a well-known method.

It is preferable that a light absorbing unit 13 used to absorb / remove all the light emitted from the visible light emitting unit 12 and transmitted through the secondary smoke SSS, so that the measurement is not affected, is disposed outside the the spontaneous combustion chamber 11 facing the visible light emitting unit 12 and, in the example shown in FIG. 3, is arranged outside the side wall 11a. A visible light transmission window 117 is provided in a part of the side wall 11a facing the light absorber unit 13.

A scattered light intensity detecting unit 14 is arranged outside the spontaneous combustion chamber 11 in the direction perpendicular to the direction of the light beam emitted from the light intensity detecting unit 12, and in an example shown in FIG. FIG. 3, the scattered light intensity detection unit 14 is arranged outside the side wall 11d. A visible light transmission window 118 is disposed in a part of the side wall 11d facing the intensity detection unit of the scattered light 14. As described above, the intensity detection unit of the scattered light 14 detects the intensity of the scattered light (hereinafter referred to as light scattered at 90 degrees) SVL, dispersed in the direction substantially perpendicular to the direction of irradiation of the visible light beam VLB between the light applied to the secondary smoke SSS and dispersed by the secondary smoke SSS. The scattered light intensity detection unit 14 is itself provided with a well-known optical system (not shown) used to collect light scattered at 90 degrees SVL and has a photoelectric converter (not shown) that converts scattered light At 90 degrees SVL collected on an electrical signal and emits electrical signal. As the photoelectric converter, a photomultiplier that converts light into a voltage signal can be preferably used. The converted voltage signal is subjected to analog-to-digital conversion, for example, and then it can be sampled with a personal computer. The data acquisition interval and the acquisition time can be set arbitrarily, and generally the measurement at 300 points can be performed in a range of 0.2 seconds for 1 minute.

The detected intensity of the light scattered at 90 degrees SVL correlates very well with the amount of visible secondary smoke, and since the detected intensity of the scattered light at 90 degrees is large, it can be determined that the amount of visible secondary smoke is relatively large It was shown that the intensity of light scattered at 90 degrees does not correlate with the total amount of particulate matter in secondary smoke.

It is preferable to install boxes for protection of the external parasitic light 17 to 19 between the visible light emitting unit 12 and the visible light transmission window 116, between the light absorption unit 13 and the visible light transmission window 117, and between the scattered light intensity detection unit 14 and the visible light transmission window 118 in order to prevent external stray light from entering through each visible light transmission window.

When a representative example of the full size of an apparatus 10 and so on is shown, the spontaneous combustion chamber 11 has a rectangular solid shape of 11 cm x 11 cm with a height of 80 cm, and the insertion opening 111 of the article for smoking is arranged in a position of 50 cm from the lower end of the spontaneous combustion chamber 11, a distance from the smoking article SA to the center of the visible light beam is 10 cm, and the visible light beam emitted from the The visible light emitting unit has a cross section with a size of 5 cm x 5 cm.

As shown in FIG. 4, the visible secondary smoke quantity measuring apparatus preferably has conversion table means 20 which convert the intensity of the scattered light at 90 degrees detected by the scattered light intensity detecting unit 14 into the amount of smoke secondary visible and that emits the amount of secondary smoke visible as a function of a correlation between the intensity of light scattered at 90 degrees and the amount of visible secondary smoke. In the media of the conversion table, the correlation between the intensity of the scattered light at 90 degrees obtained in advance and the amount of visible secondary smoke is entered as a conversion equation, a calibration curve, etc., an output The light intensity signal scattered at 90 degrees from the intensity detection unit of the scattered light 14 is converted to the visible secondary smoke quantity, and the visible secondary smoke quantity is emitted. In order to obtain the correlative relationship between the intensity of light scattered at 90 degrees and the amount of visible secondary smoke, the amount of secondary smoke visible from smoking articles, such as a large number of cigarettes, is first evaluated by evaluation sensory according to a two-point comparison method, and the amount of visible secondary smoke becomes a number. The intensity of the scattered light at 90 degrees of the same smoking article detected by this apparatus is measured. For example, when the vertical axis represents the amount of visible secondary smoke and the horizontal axis represents the intensity of the scattered light at 90 degrees, the calibration curve can be obtained by plotting the measured values obtained. The conversion equation from the intensity of the scattered light at 90 degrees with respect to the amount of visible secondary smoke can be obtained based on the calibration curve.

The sensory evaluation according to the two-point comparison method can be done using, for example, an apparatus for evaluating the amount of visible secondary smoke shown in FIG. 5. Specifically, a CIG1 standard cigarette and a CIG2 white cigarette spontaneously burned in two bilaterally symmetrical spontaneous combustion chambers 31 and 32, and a questionnaire was used with respect to the CIG1 standard cigarette that has 5 points, in which it was observed that Secondary smoke amount of the CIG2 white cigarette is within a range of 0 to 10 points. The chambers 31 and 32 are respectively provided with observation windows 311 and 321 having a fixed longitudinal width, and the visible light sources 33 and 34 are arranged in the upper portions of the respective chambers. Preferably, each longitudinal width of the observation windows 311 and 321 corresponds to the height of the visible light beam emitted from the visible light emitting unit 12 of the visible secondary smoke quantity measuring apparatus, and the distance from the CIG1 cigarettes. and CIG2 at the lower ends of the observation windows 311 and 321 correspond to a distance from the smoking article SA at the lower end of the visible light beam emitted from the visible light emitting unit 12 of the measuring apparatus of the amount of visible secondary smoke. The visible light of the visible light sources 33 and 34 is applied from above to the secondary fumes SS1 and SS2, and the secondary fumes SS1 and SS2 are observed only from the viewing windows 311 and 321.

The intensity of the scattered light at 90 degrees obtained by the apparatus measuring the amount of visible secondary smoke correlates very well with the amount of secondary smoke visible in the sensory evaluation, and this fact is demonstrated in Japanese Patent No. 3897700 In this invention, when the sensory evaluation is performed according to the two-point comparison method using the visible secondary smoke quantity evaluation apparatus shown in FIG. 5, it is confirmed that when a value of the amount of secondary visible smoke / SBR (hereinafter, referred to as the amount of visible secondary smoke) that is shown as an index in this example is not greater than 5.0 * 10-2 (min / mm), it can be determined that the amount of secondary smoke visible according to the sensory evaluation is sufficiently reduced with respect to a typical standard cigarette.

Examples

In the following, the invention will be described with reference to the examples. In the following examples, calcium carbonate PCX-850 and Cal-light-SA were purchased from Shiraishi Kogyo Kaisha, Ltd., and calcium carbonate in the form of a needle and calcium carbonate in the form of a strawberry were purchased from Newlime Co., Ltd.

The primary particle of PCX-850 is spindle-shaped, and although the primary particles form the secondary particle, it does not take the form of a strawberry. The primary particle of Cal-light-SA has a column shape, and the primary particles agglomerate to form secondary strawberry particles. The primary particle of the calcium carbonate in needle form is needle-shaped, and the primary particles do not form the secondary particle. The primary particle of the calcium carbonate in the form of a strawberry is needle-shaped, and the primary particles agglomerate to form the secondary particle in the form of a strawberry.

Comparative examples 1 to 3, examples 1 to 4 and reference examples

A pulp mixture is beaten in which the weight ratio of bleached broadleaf kraft pulp (LBKP) to bleached conifer tree kraft pulp (NBKP) is 8: 2, so that drainability is approximately 100 mL in the Canadian drainage standard, and the calcium carbonate shown in Table 1 as a filler is added to the whipped pulp mixture in a content shown in Table 1. With the use of a pulp obtained, a cigarette paper (the grammage shown in Table 1) is subjected to papermaking by a standard TAPPI sheeting machine. The aqueous solution of potassium citrate as the combustion regulating agent is coated on a surface of the cigarette paper obtained, so that the cigarette paper contains potassium citrate in an amount of 3 to 4% by weight on a dry basis. This cigarette paper is uniformized for two or more days under conditions of a temperature of 22 ° C and a relative humidity of 60% and is cut to a predetermined length. With respect to the amount of calcium carbonate in the cigarette paper, ultrasonic extraction is carried out for 30 minutes in 0.3 N aqueous hydrochloric acid, and the calcium carbonate is quantified as calcium ions by a capillary electrophoresis system ( 7100) manufactured by Agilent Technologies, and the calcium ions are converted to calcium carbonate, so that the amount of calcium carbonate in the cigarette paper is obtained.

With the use of the obtained cigarette paper and the tobacco strips (American mixture), a cigarette is produced by means of a tobacco roll (Rizla). With respect to the size of the cigarette, the circumference is 22.6 mm and the length is 67 mm. A standard filter (having a length of 31 mm) is provided to be mounted on one end of the cigarette with the use of a nozzle paper. The loading amount of the tobacco strips is 0.515 g per cigarette.

The amount of secondary smoke visible from the obtained cigarette is measured using an apparatus shown in FIGS. 3 and 4, the amount of carbon monoxide in the primary smoke is measured using a Micro-GC (3000A) manufactured by Agilent Technologies, and the amount of carbon monoxide per puff (puff) is calculated. In the measurement of the amount of secondary visible smoke, in order to correct the difference between the days in the sensitivity of a visible laser, for each measurement, the amount of secondary visible smoke of each cigarette with a measured value of the amount of secondary smoke visible in a standard cigarette (reference cigarette 3R4F) (accordingly, the unit is dimensionless). To eliminate the influence of the weight of the cigarette paper and the type and content of calcium carbonate, the standardized quantity of visible secondary smoke is divided by the spontaneous combustion ratio (SBR) (unit: mm / min) of a cigarette. The SBR is measured at a linear velocity of the atmosphere of 200 mm / s. The results are indicated in table 1.

The reference example is an example of the use of calcium carbonate (Unibur-70) (although not currently available, it is stored by the present applicant) described in Japanese Patent Application KOKAI Publication No. 59-94700.

As can be seen in the result shown in Table 1, it is confirmed that if the content of calcium carbonate is not less than 18 g / m2, the value of the amount of secondary smoke visible by spontaneous combustion ratio (SBR) is less than 5.0 * 10-2. This fact shows that the visible secondary smoke has been reduced sufficiently (examples 1 to 4). On the other hand, it will be shown that when the amount of calcium carbonate is less than 18 g / m2, including the reference example, the amount of visible secondary smoke is large (Comparative Examples 1 and 2).

Although the yield of calcium carbonate with respect to the amount of pulp in the cigarette paper depends on the amount of pulp, the maximum value is considered to be 40 to 60%, and when the yield is 40 to 50%, the grammage of the cigarette paper required to maintain not less than 18 g / m2 of calcium carbonate is assumed to be not less than 40 g / m2. When the calcium carbonate content increases further, the grammage is required to increase and, accompanying this, the amount of carbon monoxide in the secondary smoke increases. Specifically, it can be confirmed from Comparative Example 3, that when the grammage is greater than 55 g / m2, although there is a tendency to reduce the amount of visible secondary smoke, the amount of carbon monoxide in the primary smoke is increased.

According to the above, when the cigarette paper has a grammage of 40 to 55 g / m2 and contains calcium carbonate in an amount of not less than 18 g / m2, the amount of secondary smoke generated and the amount of carbon monoxide can be reduced. carbon in the primary smoke. As shown in comparative example 2, when the cigarette paper has a grammage of 42 to 50 g / m2 and contains calcium carbonate in an amount of 20 to 25 g / m2, it is possible to expect greater effects.

Reference example 5 and example 6

In the reference example 5 and in the example 6, in the calcium carbonate in which the primary particles have a comparable length (L) and the shapes of the primary particles are different, the influence of the shape of the particles was examined. primaries on the amount of visible secondary smoke and primary smoke. As calcium carbonate in which the primary particles have different forms, PCX-850 and Cal-light-SA are used. The contents of PCX-850 and Cal-light-SA are 22.5 and 23.0 g / m2, respectively. A cigarette paper was made as in the previous examples to produce a cigarette, except that the grammage of the cigarette paper and the type of calcium carbonate were changed as shown in the following Table 2. The amount of visible secondary smoke was measured. and the amount of carbon monoxide in the primary smoke of the cigarette obtained. In addition, with respect to the resulting cigarette paper, in order to examine a mechanism in which the amount of carbon monoxide in the primary smoke is reduced, the density of the cigarette paper is measured. Results are shown in table 2.

The length (L) of the primary particle described in Table 2 is an average of the length (L) of 100 primary particles measured by means of the Winroof image analysis software (Mitani Corporation) using an SEM image captured with a microscope. electronic scanning JSM-5310 manufactured by JEOL. Although the aspect ratio of calcium carbonate used in this example is indicated in Table 2, the width (W) of the primary particle is measured similar to the length (L) of the primary particle, and the ratio is calculated (L / W) of the length (L) of the primary particle with respect to the width (W).

As can be seen in the result shown in Table 2, when the calcium carbonate in which the primary particles have a column shape and the calcium carbonate in which the primary particles are spindle-shaped are compared with each other, the amount of carbon monoxide in the primary smoke of the cigarette paper using the calcium carbonate in column form is lower, and therefore, it is confirmed that the shape of the primary particle is important. With respect to the density of cigarette paper, compared to cigarette paper using calcium carbonate in which the primary particles are spindle-shaped, when calcium carbonate is used in which the primary particles are in the form of column, the reduction of the density of the cigarette paper can be confirmed. When calcium carbonate (Callight-SA) is used in which the primary particles are column-shaped, it is assumed that the density of the cigarette paper is reduced, so that the amount of carbon monoxide in the primary smoke is reduced . When considering a current manufacturing limitation, an adequate aspect ratio (L / W) of calcium carbonate in column or needle form is preferably not less than 4 and less than 10. When Cal-light is used -SA, the visible secondary smoke falls within a range of no more than 5.0 * 10-2 (min / mm), and therefore, it can be said that the amount of secondary visible smoke can be reduced sufficiently .

Reference example 7 and example 8

Next, in the calcium carbonate in which the secondary particles are strawberry-shaped, the influence of the length (L) of the primary particle on the amount of visible secondary smoke and the amount of carbon monoxide in the smoke is examined. primary. As calcium carbonate having primary particles in the form of column or needle having different length (L), calcium carbonate in the form of strawberry and Callight-SA are used.

A cigarette paper was made as in the previous examples to produce a cigarette, except that the grammage of the cigarette paper and the type of calcium carbonate were changed as shown in the following Table 3. The amount of visible secondary smoke was measured. and the amount of carbon monoxide in the primary smoke of the cigarette obtained. The results are indicated in Table 3. The length (L) of the primary particle described in Table 3 is an average of the length (L) of 100 primary particles measured according to the above method. The primary particles of calcium carbonate in the form of strawberry have an average aspect ratio of 6.7, and the primary particles of Cal-light-SA have an average aspect ratio of 9.5.

As can be seen in the result shown in Table 3, in the cigarette paper using two types of calcium carbonate in which the secondary particles similarly have a strawberry shape, it is confirmed that the amount of carbon monoxide in the primary smoke in the cigarette paper used by Cal-light-SA in which the length (L) of the primary particles is small. Therefore, it can be shown that the smaller the size of the primary particle, the greater the effect of reducing the amount of carbon monoxide in the primary smoke, and considering the variation of the length (L) of the primary particles, it is assumed that the average length (L) of the primary particles is preferably not greater than 1.5 μm.

Reference example 9 and example 10

The influence of whether secondary calcium carbonate particles are in strawberry form on the amount of visible secondary smoke and the amount of carbon monoxide in the primary smoke is examined.

A cigarette paper is manufactured as in the previous examples to produce a cigarette, except that the grammage of the cigarette paper and the type of calcium carbonate are changed as shown in the following Table 4. The amount of visible secondary smoke is measured. and the amount of carbon monoxide in the primary smoke of the cigarette obtained. The results are indicated in Table 4. In the strawberry-shaped calcium carbonate used here, the primary particles are needle-shaped, the average length (L) of the primary particles is 3.3 μm, the average aspect ratio of the primary particles is 8.0, and the secondary particles are strawberry-shaped. Meanwhile, in the needle-shaped calcium carbonate, the primary particles are needle-shaped, the average length (L) of the primary particles is 4.8 μm, and the average aspect ratio of the primary particles is 6, 7; however, the secondary particles do not have a strawberry shape. Therefore, calcium carbonate in the form of strawberry and calcium carbonate in the form of a needle are compared in which the values of the lengths (L) of the primary particles are approximately close to each other, so that it can be verified the influence of secondary particles that are or not in the form of a milling cutter on the amount of visible secondary smoke and the amount of carbon monoxide in the primary smoke.

As can be seen in the result shown in Table 4, in the cigarette paper using calcium carbonate in the form of a mill in which the secondary particles are strawberry-shaped, although the amount of visible secondary smoke is substantially equivalent compared to Cigarette paper that uses calcium carbonate in the form of a needle reduces the amount of carbon monoxide in the primary smoke. From this fact, the effect obtained when calcium carbonate is used in which the secondary particles are strawberry-shaped is confirmed. However, in cigarette paper containing calcium carbonate in which the primary particles have a large length (L), since the density of the cigarette paper is not reduced, one can expect less the reducing effect on the amount of carbon monoxide in the primary smoke and, as the length (L) of the primary particles becomes small, the greater the carbon monoxide reduction effect that can be expected. That is, in the cigarette paper that uses calcium carbonate in which the primary particles have a column or needle shape, the size of the primary particles is small, and the secondary particles are strawberry-shaped, the density is assumed to be of the cigarette paper is further reduced, and the amount of carbon monoxide in the primary smoke is further reduced.

In this example, although a cigarette having a circumference of 22.6 mm is used, a similar effect can be expected in a cigarette having a different circumference, and the invention does not limit the size of a cigarette.

Claims (5)

1. A cigarette paper having a grammage of 40 to 55 g / m2 and containing calcium carbonate in an amount of 18 g / m2 or more, characterized in that a primary particle of calcium carbonate is column-shaped or needle-shaped, and the primary particle of calcium carbonate has an average aspect ratio of not less than 4 and less than 10 and has an average length (L) of 0.1 to 1.5 pm, the secondary calcium carbonate particle is in the form of a milling cutter. 2. The cigarette paper according to claim 1, having a density of 0.4 to 1.0 g / cm3. 3. The cigarette paper according to claim 1 or 2, which contains a combustion regulating agent characterized in that it comprises an alkali metal citrate. 4. The cigarette paper according to claim 3, which contains the combustion regulating agent in an amount of 1.0 to 5.0% by weight. 5. A cigarette characterized in that it comprises: a cigarette rod including tobacco strips wrapped in the form of a rod with the cigarette paper according to any one of claims 1 to 4; Y a filter coaxially connected to one end of the cigarette rod by a nozzle paper.