Package for aerosol-generating articles having a heat-sensitive display means

Abstract

The present invention relates to a package (10) for an aerosol product (1), comprising at least one coated surface area (11) and at least one uncoated surface area (12), wherein a coating (13) on the at least one coated surface area (11) of the package (10) is heat-sensitive, and the coating (13) indicates the application of heat by a permanent color change. The present invention also relates to an aerosol product (1) comprising such a package (10), and a method for manufacturing an aerosol product (1) comprising such a package (10) by printing a polymer on a portion of the package by flexographic printing.

Description

Technical Field

[0001] The present invention relates to a package for an aerosol-generating article, and a method of manufacturing such a package, according to the preambles of claims 1 and 12 of the present application. Further, the present invention relates to an aerosol-generating smoking article having a package according to the preamble of claim 1 of the present application.

Background Art

[0002] Aerosol-generating articles are mass-produced. Examples of aerosol-generating articles are well-known cigarettes, cigars (of various sizes and shapes such as parejos, cigarillos, figurados), and recently commercially available heat-not-burn articles, which are structurally similar to cigarettes and are usually packaged in a rod shape in a paper-based package and connected to a filter portion by a tip package, and may contain tobacco material and include a filling of aerosol-generating material. These heat-not-burn articles are designed for aerosol-generating materials that are heated by an electric heating device to generate an aerosol that can be inhaled by a consumer through a mouthpiece, presumably formed by the filter. The heating of the aerosol-generating material is usually limited to a temperature of less than 400°C, preferably 250°C to 350°C, and does not cause combustion of the aerosol-generating material or the outer package of the aerosol-generating material.

[0003]

[0004] In most cases, the package is the largest outer surface of the aerosol-generating article. Usually, most of the outer surface of the package can be viewed by a consumer or others before or during use of the aerosol-generating article. Therefore, it is highly appreciated to provide a visual effect on the cigarette paper for a cigarette in order to enable differentiation from other brands of cigarettes or to provide additional information to the consumer. These visual effects can further create a high-quality appearance of the aerosol-generating article.Particularly in the case of heat-not-burn aerosol generating articles, the package may remain unchanged while the consumer is using the aerosol generating article. Therefore, it may be difficult for the user to distinguish between a new product and a used product.

[0005] It is known from the prior art that information can be provided on the package of an aerosol generating article to the consumer. As an example, embossed packages have been developed heretofore. Information can be provided by embossing letters or other symbols on the package. However, the recognition by the consumer is very limited.

[0006] It is further known in the art to provide such a smoking article comprising a thermochromic material provided on the outer package in order to provide an indication that the smoking article has already been used. Examples of such usage indication techniques are provided, for example, in WO 99 / 44447 or WO 2017 / 114895. However, the thermochromic materials used include complex chemicals (liquid crystals, leuco dyes, metal complexes) that are costly to manufacture and implement.

[0007] Therefore, an object of the present invention is to provide a package that enables easy differentiation between a new product and a used product and can be manufactured very simply and inexpensively compared to the techniques known in the prior art and can be used in an aerosol generating article. SUMMARY OF THE INVENTION PROBLEMS TO BE SOLVED BY THE INVENTION

[0008] The above problems are solved by the package according to claim 1, the aerosol generating article according to claim 10, and the method according to claim 12. MEANS FOR SOLVING THE PROBLEMS

[0009] The package according to the present invention includes at least one coated surface area and at least one uncoated surface area, and the coating of at least one coated surface area of the package is heat-sensitive. The coating indicates heat application by means of a permanent color change. Preferably, the structure of the package itself remains unchanged. This means that the package is not burned. Thereby, the generation of ash is prevented. Furthermore, the permanent structure of the package facilitates the replacement of the packaged product (e.g., a tobacco stick) after use. The coating that causes a permanent color change can be arranged on the base of the package in the form of letters or symbols. Thus, it is possible for a text or a recognizable clue for the user to appear during or after the use of the packaged product. Examples of suitable letters that may appear during heat application are the word "used" or other similar words, texts, or symbols that clearly indicate to the user that the product has already been used.

[0010] According to the present invention, the heat-sensitive coating provides an indication of heat application by means of a permanent difference in the lightness of the coated surface area, and the difference in lightness measured in accordance with ISO 2469 after heating is at least 1%, preferably at least 2%, more preferably at least 3%. It has been found that the user can particularly easily recognize the change in the lightness of the coated surface area. Furthermore, the substance that changes the lightness is convenient for use in combination with tobacco products because it does not (at least significantly) impair the flavor of the tobacco.

[0011] Preferably, the coating contains a polymer. Polymers are available in a very wide range of different compositions. Thus, the properties can be easily designed in a suitable way. Some polymers are even more preferred because their use in the tobacco industry has already been approved. Thus, the polymer is preferably selected from the group comprising EVA, PVA, any other copolymer of ethylene, any other copolymer of propylene, PE, and any other film-forming polymer. These polymers are particularly suitable because they have a minimal impact on the taste of the aerosol.

[0012] In a preferred embodiment of the package, the coating provides an indication of heat application after heat application at a temperature of at least 150°C. Thus, misrepresentation of previous use can be reliably avoided. In many cases, high temperatures occur during handling or transportation of the package (e.g., during transportation in a container), so it has been found that a very high temperature of at least 150°C is preferred for discoloration to occur. Even more preferably, the (activation) temperature is in the range of 160 to 250°C, more preferably 170 to 250°C. These temperatures are suitable for releasing all the desired flavors from the heated substrate (e.g., tobacco), and it has been found that these temperatures avoid evaporation of undesirable substrates or ignition of the tobacco or the package.

[0013] To avoid misrepresentation of previous use, a coating is selected that provides an indication of heat application after heat application for at least 3 minutes. Thus, it has been possible to avoid misrepresentation of previous use due to exposure to the minimum temperature for a very short time. Usually, it takes at least 3 minutes to consume a tobacco product, so it is preferred that exposure to the minimum temperature does not cause permanent discoloration of the coating. Preferably, exposure to the minimum temperature needs to be carried out for 5 to 15 minutes, more preferably 5 to 10 minutes, to cause permanent discoloration of the coating.

[0014] In a preferred embodiment of the package, the coating is provided in the coated surface area in an amount of 0.5 to 20 g / m 2 , preferably 2 to 15 g / m 2 , more preferably 4 to 10 g / m 2 . It has been shown that these amounts of coating do not adversely affect the permeability of the package. Thus, a continuous flow of aerosol during use of the aerosol-generating article by the user can be ensured.

[0015] Preferably, the difference in opacity in accordance with ISO 2471 between the coated surface area and the uncoated surface of the non-heat-treated package is less than 3%. As described above, it is not desirable to be able to see the color of the tobacco with a brownish tint through some areas of the package. Therefore, (semi)transparent portions should be eliminated. In contrast to the (semi)transparent portions, it is desirable to give a homogeneous appearance to the surface of the package in the non-heat-treated (or unused) state. Since consumers are accustomed to a homogeneous package surface that is mostly white, they may regard the brownish areas as being dirty or even unhygienic. To maintain such a homogeneous appearance, the difference in opacity in accordance with ISO 2471 between the coated surface area and the uncoated surface of the non-heat-treated package is preferably less than 2%, more preferably less than 1%.

[0016] Preferably, the difference in opacity in accordance with ISO 2471 between the coated surface area and the uncoated surface of the heat-treated package is less than 3%. Since the package is not charred (at least in some embodiments of the present invention), it is preferable that the difference in opacity in accordance with ISO 2471 between the coated surface area and the uncoated surface is very small after use of the product wrapped in the package. As described above, it is not desirable to be able to see the color of the tobacco with a brownish tint through some areas of the package. Therefore, (semi)transparent portions should be eliminated. In contrast to the (semi)transparent portions, it is desirable to give a homogeneous appearance to the surface of the package in the non-heat-treated (or unused) state. Since consumers are accustomed to a homogeneous package surface that is mostly white, they may regard the brownish areas as being dirty or even unhygienic. Preferably, the difference in opacity in accordance with ISO 2471 between the coated surface area and the uncoated surface of the heat-treated package is further less than 2%, more preferably less than 1% after heat application at a temperature in the range of at least 150 °C, preferably 160 - 250 °C, more preferably 170 - 250 °C.

[0017] Preferably, the coating is suitable for being applied by a known printing process, preferably flexographic printing. This facilitates the handling and application of the coating and enables parallelization, automation, and high throughput.

[0018] To facilitate the handling of the coating before application, the viscosity is preferably 200 - 2000 mPas, more preferably 300 - 1000 mPas, and even more preferably 400 - 700 mPas.

[0019] In a preferred embodiment of the package, the coated surface area contains a coating of 0.5 - 20 g / m 2 , preferably 2 - 15 g / m 2 , more preferably 4 - 10 g / m 2 . It has been found that at these coating weights, the desired gloss can be imparted with minimal material cost.

[0020] Preferably, the package contains paper. More preferably, the paper is a support on which the coating is applied. Since paper is well-known in the tobacco industry, this enables the handling of the package with known machinery and handling equipment.

[0021] In a preferred embodiment, the paper has an opacity of more than 60%, preferably more than 70%, and more preferably more than 75%. Thus, it is possible to avoid the brownish color of tobacco being clearly visible from the (uncoated) paper. Furthermore, paper with high opacity is regarded as being related to high-value and / or high-quality products.

[0022] A second aspect of the present invention relates to an aerosol-generating article comprising a wrapper as described above. An aerosol-generating article comprising such a wrapper offers the possibility of easily distinguishing between a used (tobacco) product and an unused (tobacco) product. Furthermore, (semi)transparent parts can be excluded. This gives a high-value and / or high-quality appearance that can be easily recognized by consumers. Such aerosol-generating articles do not have the drawback of being able to see the brownish color of tobacco through the wrapper. Thus, areas that are likely to be considered dirty or even unhygienic, the brownish areas, are removed. This improves the high-value and / or high-quality appearance.

[0023] In a preferred embodiment of the aerosol-generating article, the aerosol-generating article comprises an aerosol-generating substrate, which is wrapped in a wrapper as described above. Thus, the aerosol-generating substrate is wrapped in a wrapper and can be easily handled. This facilitates the replacement of a used aerosol-generating substrate with a new aerosol-generating substrate.

[0024] Preferably, the aerosol-generating substrate comprises tobacco or a tobacco extract. Thus, the packaged tobacco or tobacco extract can be easily handled by the user.

[0025] Preferably, the wrapper and the aerosol-generating substrate are part of a cartridge that can be connected to respective attachment parts of the aerosol-generating article. Such cartridges are usually designed for a specific use, so a new cartridge comprising a wrapper as described above can be easily distinguished from an already used cartridge.

[0026] In a preferred embodiment of the aerosol-generating article, the coating of the package indicates heat application by discoloration after heat application for at least 3 minutes. Thus, it is possible to avoid the initiation of false indication of heat application by exposing the aerosol-generating substrate (and / or cartridge) to a minimum temperature for a short time of less than 3 minutes without using it. Usually, it takes at least 3 minutes to consume a tobacco product, and being exposed to the minimum temperature may occur during handling and / or transportation. Therefore, it is preferred that being exposed to the minimum temperature for a shorter time does not cause permanent discoloration of the coating. Preferably, being exposed to the minimum temperature should be carried out for 5 to 15 minutes, more preferably 5 to 10 minutes, to cause permanent discoloration of the coating.

[0027] A further aspect of the present invention relates to a method for manufacturing an aerosol-generating article comprising a package, the package comprising at least one coated surface area and at least one uncoated surface area. The at least one coated surface area comprises a heat-sensitive coating applied by printing, preferably by flexographic printing, the heat-sensitive coating providing an indication of heat application by a permanent difference in lightness of the coated surface area, and the difference in lightness measured in accordance with ISO 2469 after heating is at least 1%, preferably at least 2%, more preferably at least 3%. The printing process, particularly flexographic printing, is preferred because it allows for local application of the coating, preferably the polymer. These techniques are usually available at the manufacturing site for handling the package and / or paper, so no additional machinery or equipment is required. Furthermore, flexographic printing enables very high-speed printing and high throughput. This is particularly desirable for mass-produced products such as packages for tobacco (containing) sticks.

[0028] In a preferred embodiment, the method includes the step of selecting a suitable heat-sensitive coating. This heat-sensitive coating preferably includes a polymer. The polymer is preferably selected from the group consisting of EVA, PVA, any other copolymer of ethylene, any other copolymer of propylene, PE, and any other film-forming polymer. These polymers have been found to be particularly suitable for the printing process, especially flexographic printing.

[0029] In a preferred embodiment of the method, the polymer is printed as an emulsion, as a suspension, or in a molten form. This facilitates the handling and uniform distribution of the polymer. Preferably, the emulsion, suspension, or molten polymer is dried after application to the (raw) paper. In a more preferred embodiment, this drying is carried out under at least temporarily elevated pressure. In at least some cases, the elevated pressure enables strong adhesion of the polymer to the paper. This improves the heat transfer from the inner surface to the outer surface of the package.

[0030] All disclosed features related to this method are to be applied to the package and / or aerosol-generating article with necessary modifications, and all disclosed features related to the package and / or aerosol-generating article are to be applied to the method with necessary modifications.

[0031] Further advantages, objects, and features of the present invention will be described by way of example only in the following description with reference to the accompanying drawings. In the figures, similar components in different embodiments can be denoted by the same reference numerals.

Brief Description of the Drawings

[0032]

Fig. 1a

Fig. 1b

Fig. 2a

Fig. 2b

Fig. 3a

Fig. 3b

Fig. 3c

Fig. 3d

Fig. 3e

Fig. 3f

Fig. 3g

DETAILED DESCRIPTION OF THE INVENTION

[0033] FIG. 1a shows images of two aerosol generating articles 1a, 1b, each aerosol generating article 1a, 1b being surrounded by a package 10 having a coated surface area 11 and an uncoated surface area 12 according to the present invention. The package 10 surrounds the side area of a cylinder 2 (geometrically more specifically, a right circular cylinder) made of tobacco (not shown).

[0034] The package 10 is partially, i.e., in the coated area 11, coated with a heat-sensitive coating 13. In the illustrated embodiment, this coating is applied in a parallel stripe pattern on the package 10, and then the package 10 is wrapped around the tobacco cylinder 2. In this curved form of the package 10, the coated area 11 surrounds the cylinder along its circumferential direction.

[0035] On the left side of FIG. 1a, a used aerosol-generating article 1a is shown. In contrast, the aerosol-generating article 1b on the right side has not been used. The coating 13 is barely visible before use of the aerosol-generating article 1b (right), but the local coating 13 is clearly visible after use (left). Since the coating 13 indicates heat treatment by permanent discoloration, a striped pattern appears along the periphery of the tobacco stick 1 during use. Thus, even if the aerosol-generating article 1 and / or the package 10 are not burnt during tobacco consumption and / or during use of the aerosol-generating article 1, their use is clearly indicated. This indicator prevents misidentification and repeated use of a single aerosol-generating article 1. The sample shown in FIG. 1a is made using a commercially available aerosol-generating article packaged in a package 10 according to an embodiment of the present invention. The aerosol-generating article shown on the left side of FIG. 1a has been processed by a smoking device that simulates use / consumption by a user.

[0036] FIG. 1b shows a further embodiment of the package 10. The pattern 14 of the coated area 11 is a striped pattern. Thus, such a cigarette wrapper 10 or a very similar cigarette wrapper 10 could have been used in the manufacture of the aerosol-generating article 1 as shown in FIG. 1a. The base paper was locally coated with a polymer. In this embodiment, a polymer that has been used hitherto in the tobacco industry as an adhesive for attaching the overlapping ends of the cigarette wrapper to each other was used. The application was carried out by printing, in this case by flexographic printing. The polymer was applied in an amount of about 6 g / m 2 to the printed area. In this embodiment, about 43% (preferably 40 - 50%) of the entire upper surface of the (base) paper 10 was coated with the polymer.

[0037] In the embodiment of the package 10 shown in FIG. 1b, the opacity of the coated area 11 and the uncoated area 12 was measured. The measured difference in opacity between these areas was very small. The opacity of the coated area 11 was determined to be 74.9% and the opacity of the uncoated area 12 was measured to be 75.6%.

[0038] Figure 2a shows a detailed image of a possible form of the coated surface 13 on the package 10 before heat application. This sample was made based on paper available from the Miquel y Costas Group. In the illustrated embodiment, the coating 13 is applied with a pattern 14 that forms letters on the substrate. Since a white or transparent polymer was used, the coating 13 is only visible before heat application. However, depending on the angle of the light hitting the coating 13, the coating 13 can be recognizable because it has a gloss.

[0039] Figure 2b shows a cutout of the same package as shown in Figure 2a. However, the cutout shown in Figure 2b is locally heated. Two circular heat sources (not shown) are used for heat application. The heat-treated area of the package 10 is visible because the base paper and the coating 13 have changed color. However, the paper and the coating 13 have changed color to different colors. Therefore, the letters 14 become clearly visible. Note that the angle of the light has changed for the illustration in Figure 2b. At this angle, the gloss of the coating 13 is no longer visible. Therefore, the pattern 14 could not be confirmed or could only be speculated in some of the non-heat-treated areas. In contrast, due to the different colors within the heat-treated area, the pattern is visible.

[0040] Figures 3a to 3g illustrate the effects of different heat treatments. All of Figures 3a to 3g show detailed images of possible forms of the coated surface on the package after heat application with a circular heat application device. Also, these samples were prepared based on the same paper available from the Miquel y Costas Group. The processing time and / or processing temperature differ among the samples shown in the figures. The packages shown in Figures 3a and 3b were both processed at a temperature of about 250°C. The package shown in Figure 3a was processed for 60 seconds, while the package shown in Figure 3b was processed for 300 seconds. After only 60 seconds of processing (Figure 3a) at this temperature, it was confirmed that the pattern was not yet clearly visible. However, a long processing of 600 seconds caused significant discoloration and the pattern 14 (characters) was visible.

[0041] After processing the package 10 using a 300°C heat application device, the pattern was already visible after only 30 seconds of processing (Figure 3c). However, longer processing of 60 seconds (Figure 3d) and 300 seconds (Figure 3e) further enhanced the visibility. In Figure 3e, due to heat radiation, the surrounding area of the package 10 is also tinged brown, and it can be confirmed that the circular pattern of the heat application device is non-uniform.

[0042] Figures 3f and 3g show the package 10 after processing the package 10 using a 350°C heat application device. This pattern could already be confirmed after only 30 seconds (Figure 3f) and 60 seconds (Figure 3g) of processing. However, both packages are locally charred.

[0043] The polymer used for the coating as shown in Figures 3a to 3g was EVA having a viscosity of 600 mPa·s at 20°C. The solid content was 48% (w / w), and the coating temperature was 15 - 25°C. No discoloration was visible for this polymer after heat treatment at 200°C or lower.

[0044] The applicant reserves the right to claim, as essential features of the invention, all the features disclosed in the present application specification, provided that, in light of the prior art, those features are new, either individually or in combination. Further, it should be noted that in the figures, features that may be advantageous individually are described. A person skilled in the art will immediately recognize that the specific features disclosed in the figures may be advantageous without incorporating further features of this figure. Further, a person skilled in the art will recognize that advantages may arise from combinations of the various features disclosed in one or more of the figures.

Description of the Reference Numerals

[0045] 1 Aerosol generating article 1a Used aerosol generating article 1b Unused aerosol generating article 2 Cylinder 10 Package 11 Coated surface area 12 Uncoated surface area 13 Coating 14 Pattern

Claims

1. A package for packaging an aerosol-generating substrate, comprising at least one coated surface area coated with a heat-sensitive coating arranged to indicate heat application by permanent discoloration and at least one uncoated surface area, wherein the heat-sensitive coating provides an indication of heat application by a permanent difference in lightness of the coated surface area, wherein the heat-sensitive coating comprises a polymer selected from the group consisting of EVA, PVA, and PE, The heat-sensitive coating is provided in the coated surface area in an amount of 0.5 to 20 g / m ２ ², characterized by the package.

2. The package according to claim 1, wherein the heat-sensitive coating provides an indication of heat application after heat application at a temperature of at least 150°C.

3. The package according to claim 1 or 2, wherein the heat-sensitive coating provides an indication of heat application after heat application for at least 3 minutes.

4. The package according to any one of claims 1 to 3, wherein the difference in opacity in accordance with ISO 2471 between the coated surface area and the uncoated surface area of the package before heat treatment is less than 3%.

5. The package according to any one of claims 1 to 4, wherein the difference in opacity in accordance with ISO 2471 between the coated surface area and the uncoated surface area of the package after heat treatment is less than 3% after heat application at a temperature of at least 150°C.

6. An aerosol-generating article comprising the package according to any one of claims 1 to 5.

7. The aerosol-generating article according to claim 6, wherein the heat-sensitive coating of the package indicates heat application by discoloration after heat application for at least 3 minutes.

8. A method of manufacturing an aerosol-generating article comprising a package, the package comprising at least one coated surface area and at least one uncoated surface area, wherein the at least one coated surface area is coated by flexographic printing and comprises a heat-sensitive coating configured to provide an indication of heat application by a permanent difference in lightness of the coated surface area, wherein the heat-sensitive coating comprises a polymer selected from the group consisting of EVA, PVA, and PE, The heat-sensitive coating is provided in the coating surface area in an amount of 0.5 to 20 g / m ２ 2 characterized by the method.

9. The method according to claim 8, wherein the heat-sensitive coating is dried after application to the package.

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