A cigarette paper and a method for manufacturing the same

Abstract

The application discloses a kind of cigarette paper and preparation method thereof, belong to papermaking technical field.Cigarette paper is prepared by pulp, calcium carbonate and additive, the calcium carbonate is the mixture of liquid precipitated calcium carbonate and powder precipitated calcium carbonate, the crystal form of liquid precipitated calcium carbonate single crystal is fusiform, the length of liquid precipitated calcium carbonate single crystal is 1200-1850nm, the diameter of liquid precipitated calcium carbonate single crystal is 200-290nm, the length-diameter ratio of liquid precipitated calcium carbonate single crystal is 4.5-7.0, and the weight ratio of liquid precipitated calcium carbonate in the calcium carbonate is 10%-100%.In the application, higher rib strength is achieved under lower rib roller pressure by using liquid precipitated calcium carbonate with specific parameters, and the service life of the encapsulating roller is improved.Furthermore, using liquid precipitated calcium carbonate will not have negative impact on other properties of the paper.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of papermaking, more particularly, to a cigarette paper and a preparation method thereof. BACKGROUND

[0002] Cigarette paper is a kind of thin paper used for wrapping tobacco to make cigarettes, which is prepared from pulp, calcium carbonate and additives. The cigarette paper is white, tight, soft and delicate, has high opacity, high longitudinal tensile strength, certain air permeability and suitable burning speed.

[0003] Rib is an important appearance index of cigarette paper. Rib refers to the embossing left on the cigarette paper by mechanical action. The embossing process is generally divided into three types, i.e. wet embossing, dry embossing and off-machine embossing. The off-machine embossing is rarely used, and the dry embossing is limited in application range because of high pressure, great damage to equipment and difficulty in controlling the stability of rib strength. The wet embossing is performed on the paper web after it leaves the press section and before it enters the drying section. At this time, the paper web has been initially formed and has not been subjected to the drying process. The paper fibers are soft and easy to be pressed into shape. At present, most of the domestic and foreign high-grade cigarette paper machines adopt the wet embossing process. The equipment for embossing cigarette paper is a pair of rib rollers, one of which is a steel silk roller with the required pattern engraved on the surface, and the other is a rubber-coated roller which is generally replaced regularly or irregularly according to the use state.

[0004] The rib strength of cigarette paper reflects the depth of the rib of cigarette paper. The higher the rib strength of cigarette paper is, the deeper and clearer the rib of cigarette paper is. The cigarette paper manufacturing industry generally uses visual inspection to measure the rib strength of cigarette paper. However, the subjectivity of visual inspection is strong, and there are too many factors affecting the judgment of rib strength. In recent years, the industry has gradually promoted the use of cigarette paper rib strength testers to quantify the rib strength of cigarette paper.

[0005] For cigarettes, the style and strength of the rib of cigarette paper affect the style of cigarettes to some extent. Therefore, cigarette companies pay more and more attention to the rib strength of cigarette paper when selecting cigarette paper for products. The rib strength is gradually included in the standard requirements, and even affects the selection of cigarette paper.

[0006] In the production process of cigarette paper, increasing the rib roller pressure is the most direct and effective way to improve the rib strength of cigarette paper. This is because the greater the rib roller pressure acting on the paper web, the greater the pressure of the embossing roller on the paper web, the lower the opacity of the embossed area, and the greater the difference in opacity between the embossed area and the non-embossed area. Therefore, the rib strength of cigarette paper is higher. However, the adjustment space for rib strength is very limited by this method. Moreover, too high rib roller pressure will significantly shorten the service life of the rubber-coated roller, increase production costs, and prolong downtime for replacing the rubber-coated roller, thereby reducing production efficiency. SUMMARY

[0007] The technical problem solved by the present application is to overcome the defects and deficiencies of the prior art that increasing the rib strength of the cigarette paper by increasing the rib roller pressure leads to a reduced service life of the rib roller and a limited increase in the rib strength, and to provide a cigarette paper that achieves a higher rib strength at a lower rib roller pressure by compounding liquid precipitated calcium carbonate and powder precipitated calcium carbonate with specific parameters, and improves the service life of the encapsulating roller.

[0008] Another object of the present application is to provide a preparation method of the cigarette paper.

[0009] The above objects of the present application are achieved by the following technical solutions.

[0010] A cigarette paper prepared from pulp, calcium carbonate and additives, wherein the calcium carbonate is a mixture of liquid precipitated calcium carbonate and powder precipitated calcium carbonate, the crystal form of the liquid precipitated calcium carbonate monocrystal is fusiform, the length of the liquid precipitated calcium carbonate monocrystal is 1200-1850 nm, the diameter of the liquid precipitated calcium carbonate monocrystal is 200-290 nm, and the aspect ratio of the liquid precipitated calcium carbonate monocrystal is 4.5-7.0.

[0011] The weight ratio of the liquid precipitated calcium carbonate in the calcium carbonate is 10%-100%.

[0012] In the art, calcium carbonate can be divided into liquid calcium carbonate and powder calcium carbonate.

[0013] Liquid calcium carbonate can be prepared by precipitation or grinding.

[0014] The liquid precipitated calcium carbonate of the present application refers to liquid calcium carbonate prepared by precipitation.

[0015] In the present application, the liquid precipitated calcium carbonate and the powder precipitated calcium carbonate with specific parameters are compounded to achieve a higher rib strength at a lower rib roller pressure, and improve the service life of the encapsulating roller. Moreover, the use of liquid precipitated calcium carbonate does not negatively affect other properties of the paper. This may be because: the suspension after the preparation of liquid precipitated calcium carbonate does not go through a drying stage, and the crystal structure is more complete, with sharper crystal form tips, which are easily embedded in the fibers under external pressure, thereby reducing the interface between the calcium carbonate particles and the fibers; under the condition that the size of the dimers is consistent, the calcium carbonate with a larger aspect ratio of monocrystal can embed more volume into the fibers under the action of external force, which can further reduce the interface between the calcium carbonate particles and the fibers, the scattering surface and the reflecting surface of the irradiation light, thereby improving the transparency of the rib pressure zone and increasing the contrast with the rib non-pressure zone, i.e. improving the rib strength.

[0016] The crystal form of the liquid precipitated calcium carbonate monocrystal, the length of the liquid precipitated calcium carbonate monocrystal, and the diameter of the liquid precipitated calcium carbonate monocrystal are measured by scanning electron microscopy, and are obtained by statistical calculation.

[0017] The aspect ratio of the liquid precipitated calcium carbonate monocrystal is obtained by the ratio of the length of the monocrystal to the diameter of the monocrystal.

[0018] The length of the liquid precipitated calcium carbonate monocrystal can be 1200 nm, 1300 nm, 1400 nm, 1500 nm, 1600 nm, 1700 nm, 1800 nm, or 1850 nm.

[0019] The diameter of the liquid precipitated calcium carbonate monocrystal can be 200 nm, 210 nm, 220 nm, 230 nm, 240 nm, 250 nm, 260 nm, 270 nm, 280 nm, or 290 nm.

[0020] The aspect ratio of the liquid precipitated calcium carbonate monocrystal can be 4.5, 5.0, 5.5, 6.0, 6.5, or 7.0.

[0021] Preferably, in the cigarette paper, the liquid precipitated calcium carbonate monocrystals combine to form calcium carbonate polymers, and the D50 of the polymers is 1.6-2.2 μm.

[0022] In the precipitated calcium carbonate, the calcium carbonate monocrystals can combine to form calcium carbonate polymers similar to chrysanthemum petals. The inventors have found that the D50 of the polymers also affects the rib strength, opacity, and retention of the calcium carbonate of the cigarette paper. When the D50 of the polymers is 1.8-2.0 μm, the rib strength, opacity, and retention are higher.

[0023] D50 represents that the volume of the particles with a particle size less than it and greater than it each accounts for 50% of the total volume.

[0024] In the present application, the D50 of the polymers is detected by a SediGraph III 5120 type sedimentation particle size instrument.

[0025] It should be noted that the liquid precipitated calcium carbonate monocrystals combine to form calcium carbonate polymers, which are not spherical particles per se. The "diameter" is the equivalent spherical diameter, and does not represent the absolute diameter in the usual sense. It represents a distribution, i.e. an integral curve continuously varying from an upper limit value to a lower limit value. The diameter here is the statistical average of all the varying values.

[0026] In the present application, the weight ratio of the liquid precipitated calcium carbonate to the calcium carbonate can be 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, or 100%.

[0027] Preferably, the length of the liquid precipitated calcium carbonate monocrystal is 1250-1500 nm.

[0028] Preferably, the diameter of the liquid precipitated calcium carbonate monocrystal is 200-260 nm.

[0029] Preferably, the length-diameter ratio of the liquid precipitated calcium carbonate monocrystal is 5.3-6.1.

[0030] Preferably, the weight ratio of the liquid precipitated calcium carbonate in the calcium carbonate is 50%-100%.

[0031] In the present application, the proportion of the liquid precipitated calcium carbonate in the calcium carbonate is high, which is beneficial to further improve the rib strength.

[0032] Preferably, the crystal form of the powder precipitated calcium carbonate monocrystal is fusiform, the length of the powder precipitated calcium carbonate monocrystal is 901-1194 nm, the diameter of the powder precipitated calcium carbonate monocrystal is 364-425 nm, and the length-diameter ratio of the powder precipitated calcium carbonate monocrystal is 2.3-3.2.

[0033] Preferably, the mass fraction of the calcium carbonate is 28%-40% based on the mass of the cigarette paper.

[0034] More preferably, the mass fraction of the calcium carbonate is 30%-35% based on the mass of the cigarette paper.

[0035] The mass fraction of the calcium carbonate is generally determined by the ash content after the finished paper is burned.

[0036] Preferably, the rib strength of the cigarette paper is greater than 9.0%.

[0037] More preferably, the rib strength of the cigarette paper is greater than 10.5%.

[0038] The rib strength is detected by using an ECMO IAS type rib strength instrument.

[0039] The present application also protects the preparation method of the cigarette paper, which comprises the following steps: mixing pulp, calcium carbonate and additives to obtain mixed pulp, and after the mixed pulp is dehydrated, shaped, pressed, embossed, sized and dried, the cigarette paper is obtained; wherein when embossing, the rib pressure is 20-120 kN / m.

[0040] Preferably, the rib pressure is 20-60 kN / m.

[0041] The cigarette paper prepared by using the calcium carbonate of the present application can achieve higher rib strength under lower rib roller pressure, which is beneficial to improve the service life of the encapsulating roller.

[0042] Compared with the prior art, the present application has the following beneficial effects:

[0043] The application discloses a cigarette paper. Liquid precipitated calcium carbonate and powder precipitated calcium carbonate are compounded through specific parameters, higher rib strength is realized under lower rib roller pressure, and the service life of a gumming roller is improved. Moreover, the use of liquid precipitated calcium carbonate does not have negative effects on other performances of the paper. BRIEF DESCRIPTION OF DRAWINGS

[0044] Figure 1 The scanning electron microscope image of the liquid precipitated calcium carbonate in Example 1 is enlarged 10,000 times.

[0045] Figure 2 The scanning electron microscope image of the powder precipitated calcium carbonate in Comparative Example 1 is enlarged 10,000 times.

[0046] Figure 3 The appearance diagram of the cigarette paper in Example 1 is shown.

[0047] Figure 4 The appearance diagram of the cigarette paper in Comparative Example 1 is shown. DETAILED DESCRIPTION

[0048] The application will be further described in connection with the specific embodiments, but the embodiments do not limit the application in any form. Unless otherwise specified, the raw materials used in the embodiments of the application are conventional raw materials purchased.

[0049] Liquid precipitated calcium carbonate, Zhongyan Modi (Jiangmen) Paper Co., Ltd. Calcium Carbonate Satellite Factory, the liquid precipitated calcium carbonate in each embodiment is obtained by customization / selection from the above factory.

[0050] Powder precipitated calcium carbonate, Solvay Chemicals International SA, Socal 92E brand.

[0051] The test method of the length of the calcium carbonate single crystal is as follows: after scanning electron microscope shooting, the calcium carbonate single crystal in the obtained picture is analyzed and measured by using NanoMeasuer software, the length of the single crystal is measured in more than 50 on each picture, and more than 5 pictures are measured for each sample; the obtained data are analyzed by using Origin software, and the length range of the single crystal is obtained.

[0052] The test method of the diameter of the calcium carbonate single crystal is as follows: after scanning electron microscope shooting, the calcium carbonate single crystal in the obtained picture is analyzed and measured by using NanoMeasuer software, the diameter of the single crystal is measured in more than 50 on each picture, and more than 5 pictures are measured for each sample; the obtained data are analyzed by using Origin software, and the diameter range of the single crystal is obtained.

[0053] The method for testing the length-diameter ratio of the calcium carbonate single crystal is as follows: the length-diameter ratio is calculated by using the length value and the diameter value of the single crystal obtained by the measurement, and then analyzed by using Origin software to obtain the length-diameter ratio range of the single crystal.

[0054] The method for testing the D50 of the calcium carbonate polymer formed by combining the calcium carbonate single crystals is as follows: a SediGraph III5120 type sedimentation particle size instrument is used for detection.

[0055] Example 1

[0056] A cigarette paper is prepared from pulp, liquid precipitated calcium carbonate and additives, the crystal form of the liquid precipitated calcium carbonate single crystal is shuttle-shaped, the length of the liquid precipitated calcium carbonate single crystal is 1250-1443 nm, the diameter of the liquid precipitated calcium carbonate single crystal is 204-257 nm, and the length-diameter ratio of the liquid precipitated calcium carbonate single crystal is 5.3-6.1.

[0057] A plurality of liquid precipitated calcium carbonate single crystals combine to form calcium carbonate polymers, and the D50 of the polymers is 1.99 μm.

[0058] The preparation method of the cigarette paper comprises the following steps: mixing the pulp, the liquid precipitated calcium carbonate and the additives to obtain a mixed pulp, and after dehydration, molding, pressing, embossing, sizing and drying of the mixed pulp, the cigarette paper is obtained; wherein, during the embossing, the rib pressure is 40 kN / m.

[0059] Example 2

[0060] A cigarette paper, which is different from that of Example 1 in the preparation method of the cigarette paper, wherein during the embossing, the rib pressure is 35 kN / m.

[0061] Example 3

[0062] A cigarette paper, which is different from that of Example 1 in that the crystal form of the liquid precipitated calcium carbonate is shuttle-shaped, the length of the liquid precipitated calcium carbonate single crystal is 1671-1839 nm, the diameter of the liquid precipitated calcium carbonate single crystal is 241-289 nm, and the length-diameter ratio of the liquid precipitated calcium carbonate single crystal is 6.2-7.0.

[0063] A plurality of liquid precipitated calcium carbonate single crystals combine to form calcium carbonate polymers, and the D50 of the polymers is 2.04 μm.

[0064] The rest is the same as Example 1.

[0065] Example 4

[0066] A cigarette paper, which is different from example 1 in that the crystal form of the liquid precipitated calcium carbonate is shuttle-shaped, the length of the liquid precipitated calcium carbonate monocrystal is 1254-1447 nm, the diameter of the liquid precipitated calcium carbonate monocrystal is 244-290 nm, and the length-diameter ratio of the liquid precipitated calcium carbonate monocrystal is 4.5-5.2.

[0067] The several liquid precipitated calcium carbonate monocrystals combine to form a calcium carbonate aggregate, and the D50 of the aggregate is 2.01 μm.

[0068] The rest is the same as example 1.

[0069] Example 5

[0070] A cigarette paper, which is prepared from pulp, calcium carbonate and additives, the calcium carbonate is a mixture of liquid precipitated calcium carbonate and powder precipitated calcium carbonate, the crystal form of the liquid precipitated calcium carbonate monocrystal is shuttle-shaped, the length of the liquid precipitated calcium carbonate monocrystal is 1250-1443 nm, the diameter of the liquid precipitated calcium carbonate monocrystal is 204-257 nm, and the length-diameter ratio of the liquid precipitated calcium carbonate monocrystal is 5.3-6.1. The several liquid precipitated calcium carbonate monocrystals combine to form a calcium carbonate aggregate, and the D50 of the aggregate is 1.99 μm.

[0071] The crystal form of the powder precipitated calcium carbonate monocrystal is shuttle-shaped, the length of the powder precipitated calcium carbonate monocrystal is 901-1194 nm, the diameter of the powder precipitated calcium carbonate monocrystal is 364-425 nm, and the length-diameter ratio of the powder precipitated calcium carbonate monocrystal is 2.3-3.2. The several powder precipitated calcium carbonate monocrystals combine to form a calcium carbonate aggregate, and the D50 of the aggregate is 2.05 μm.

[0072] The weight ratio of the liquid precipitated calcium carbonate in the calcium carbonate is 50%, and the weight ratio of the powder precipitated calcium carbonate in the calcium carbonate is 50%.

[0073] The rest is the same as example 1.

[0074] Example 6

[0075] A cigarette paper, which is different from example 5 in that the weight ratio of the liquid precipitated calcium carbonate in the calcium carbonate is 10%, and the weight ratio of the powder precipitated calcium carbonate in the calcium carbonate is 90%.

[0076] The rest is the same as example 5.

[0077] Comparative example 1

[0078] A cigarette paper, which is prepared from pulp, powder precipitated calcium carbonate and additives, the crystal form of the powder precipitated calcium carbonate monocrystal is shuttle-shaped, the length of the powder precipitated calcium carbonate monocrystal is 901-1194 nm, the diameter of the powder precipitated calcium carbonate monocrystal is 364-425 nm, and the length-diameter ratio of the powder precipitated calcium carbonate monocrystal is 2.3-3.2.

[0079] The several powder precipitated calcium carbonate monocrystals combine to form calcium carbonate polymers, and the D50 of the polymers is 2.05 μm.

[0080] The rest is the same as Example 1.

[0081] Comparative Example 2

[0082] A cigarette paper, which is different from Comparative Example 1 in that the cigarette paper is prepared by a method in which the ribbing pressure is 100 kN / m.

[0083] The rest is the same as Comparative Example 1.

[0084] Comparative Example 3

[0085] A cigarette paper prepared from pulp, liquid precipitated calcium carbonate and additives, the crystal form of the liquid precipitated calcium carbonate monocrystals is fusiform, the length of the liquid precipitated calcium carbonate monocrystals is 903-1201 nm, the diameter of the liquid precipitated calcium carbonate monocrystals is 366-431 nm, and the aspect ratio of the liquid precipitated calcium carbonate monocrystals is 2.3-3.2.

[0086] The several liquid precipitated calcium carbonate monocrystals combine to form calcium carbonate polymers, and the D50 of the polymers is 2.08 μm.

[0087] The rest is the same as Example 1.

[0088] Results detection

[0089] The cigarette papers of the above examples and comparative examples are tested by the following performance test methods:

[0090] (1) Ribbing strength: tested by a ribbing strength tester with a model of EMCO IAS, and the unit of ribbing strength is %.

[0091] (2) Paper ash content: determined according to GB / T 742-2018.

[0092] (3) Paper basis weight: determined according to GB / T 451.2-2023.

[0093] (4) Paper opacity: determined according to GB / T 1543-2005.

[0094] (5) Service life of the rubber-covered roller: comprehensively judged according to the uniformity, stability and clarity of the product ribs, etc., and the same standard is used to judge each example and comparative example.

[0095] The specific test results are described in Table 1 below:

[0096]

[0097] The appearance of the cigarette paper of Example 1 is shown in Fig. 1. Figure 3

[0098] The appearance of the cigarette paper of Comparative Example 1 is shown in Fig. 1. Figure 4

[0099] From the above data, it can be seen that the cigarette paper of the present application, by compounding the liquid precipitated calcium carbonate and the powder precipitated calcium carbonate with specific parameters, can achieve higher rib strength at lower rib roller pressure, and improve the service life of the rib roller. When the rib roller pressure is 35-87 kN / m, the rib strength of the paper can be increased to 10.5-13.4%, and the service life of the rib roller can reach 116-144 hours. The opacity of the paper can be seen, and the other performance of the cigarette paper of the present application is stable, which shows that the present application does not have a negative impact on the quality parameters of the cigarette paper.

[0100] From Example and Comparative Example 1 and Figure 3 , Figure 4 It can be seen that the cigarette paper is prepared by using powder precipitated calcium carbonate, and when the rib roller pressure is 40 kN / m, the rib strength of the paper is only 6.8%, which is very low.

[0101] From Example, Comparative Example 1 and Comparative Example 2, it can be seen that the cigarette paper is prepared by using powder precipitated calcium carbonate, and when the rib roller pressure is increased to 100 kN / m, the rib strength of the paper can only be increased to 10.3%, and the service life of the rib roller is greatly reduced, only 50 hours, so it is necessary to frequently stop and replace the rib roller, which prolongs the downtime and significantly increases the production cost and reduces the production efficiency.

[0102] From Example and Comparative Example 3, it can be seen that although the cigarette paper is also prepared by using liquid precipitated calcium carbonate, the single crystal length of the liquid precipitated calcium carbonate, the single crystal diameter of the liquid precipitated calcium carbonate and the aspect ratio of the liquid precipitated calcium carbonate are different from Example, and when the rib roller pressure is 40 kN / m, the rib strength of the paper can only be increased to 8.9%, which cannot meet the requirements.

[0103] From Example 1, Example 3 and Example 4, it can be seen that the length of the single crystal of the liquid precipitated calcium carbonate is 1250-1500 nm, and the aspect ratio of the single crystal of the liquid precipitated calcium carbonate is 5.3-6.1, which is more conducive to improving the rib strength.

[0104] From Example 1, Example 5 and Example 6, it can be seen that the weight ratio of the liquid precipitated calcium carbonate in the calcium carbonate is 50%-100%, which is more conducive to improving the rib strength.

[0105] ​​Obviously, the above embodiments of the present application are merely exemplary but not intended to limit the embodiments of the present application. Based on the above description, any other variations or changes can be made by those skilled in the art without departing from the spirit and principles of the present application. It is not necessary to list all the embodiments here. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present application shall fall within the scope of the claims of the present application.

Claims

1. A cigarette paper, characterized by, The cigarette paper is prepared from a pulp, calcium carbonate and an additive, and the preparation method comprises the following steps: mixing the pulp, the calcium carbonate and the additive to obtain mixed pulp, and then dehydrating, shaping, pressing, embossing, sizing and drying the mixed pulp to obtain the cigarette paper; wherein the embossing is performed at a rib pressure of 20-60 kN / m. The calcium carbonate is a mixture of liquid precipitated calcium carbonate and powder precipitated calcium carbonate, the liquid precipitated calcium carbonate monocrystal has a spindle shape, the length of the liquid precipitated calcium carbonate monocrystal is 1200-1850 nm, the diameter of the liquid precipitated calcium carbonate monocrystal is 200-290 nm, and the aspect ratio of the liquid precipitated calcium carbonate monocrystal is 4.5-7.

0. The weight ratio of the liquid precipitated calcium carbonate in the calcium carbonate is 50%-100%. In the cigarette paper, a plurality of the liquid precipitated calcium carbonate monocrystals are combined to form calcium carbonate polymers, and the D50 of the polymers is 1.6-2.2 μm. The rib strength of the cigarette paper is greater than 9.0%.

2. The cigarette paper of claim 1, wherein, The length of the liquid precipitated calcium carbonate monocrystal is 1250-1500 nm.

3. The cigarette paper of claim 1, wherein, The aspect ratio of the liquid precipitated calcium carbonate monocrystal is 5.3-6.

1.

4. The cigarette paper of claim 1, wherein, The powder precipitated calcium carbonate monocrystal has a spindle shape, the length of the powder precipitated calcium carbonate monocrystal is 901-1194 nm, the diameter of the powder precipitated calcium carbonate monocrystal is 364-425 nm, and the aspect ratio of the powder precipitated calcium carbonate monocrystal is 2.3-3.

2.

5. The cigarette paper of claim 1, wherein, The mass fraction of the calcium carbonate in the cigarette paper is 28%-40%.

6. The method of producing a cigarette paper according to any one of claims 1 to 5, wherein The preparation method comprises the following steps: mixing the pulp, the calcium carbonate and the additive to obtain mixed pulp, and then dehydrating, shaping, pressing, embossing, sizing and drying the mixed pulp to obtain the cigarette paper; wherein the embossing is performed at a rib pressure of 20-60 kN / m.

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