Filter For Smoking or Vaping Article Comprising a Two-Layer Material

Abstract

The invention provides a material which comprises a paper substrate and a nonwoven substrate having a low density which can be used as filter for a smoking or vaping article.

Claims

1. Filter comprising a two-layer material comprising: a paper substrate having a density of between 500 mg/cm.sup.3 and 200 mg/cm.sup.3, and a nonwoven substrate having a density of between 7 mg/cm.sup.3 and 60 mg/cm.sup.3.

2. Filter according to claim 1, wherein the paper substrate:nonwoven substrate mass ratio is between 10:90 and 90:10.

3. Filter according to claim 1, wherein the paper substrate has a thickness of between 50 μm and 200 μm.

4. Filter according to claim 1, wherein the nonwoven substrate has a thickness of between 700 μm and 6000 μm.

5. Filter according to claim 1, wherein the nonwoven substrate comprises natural fibres chosen from wood fibres, leaf fibres, fruit fibres, seed fibres, bast fibres, stalk fibres, reed fibres, and mixtures thereof.

6. Filter according to claim 1, wherein the nonwoven substrate is consolidated by chemical consolidation, by needling, by hydroentanglement, or combinations thereof.

7. Filter according to claim 1, wherein the nonwoven substrate is capable of being obtained by a drylaid process or by an airlaid process.

8. Filter according to claim 1 for a smoking or vaping article.

9. Smoking article comprising a filter as defined in claim 8.

10. Vaping article comprising a filter as defined in claim 8.

11. Process for producing a filter for a smoking or vaping article as defined in claim 8, said process comprising the following steps: a) producing the paper substrate by a wetlaid process, b) optionally shaping the paper substrate produced in step a), c) producing the nonwoven substrate by a drylaid process or by an airlaid process, d) combining the paper substrate produced in step a) or b) and the nonwoven substrate produced in step c) to produce a two-layer material, e) forming a rod from the two-layer material produced in step d), f) wrapping the rod with a sheet of plug wrap paper, g) depositing an adhesive line at the junction of the sheet of plug wrap paper to obtain a rod of filtering material, h) cutting the rod of filtering material to produce the filter.

Description

EXAMPLES

Example 1

Manufacture of a Two-Layer Material

Example 1.1

Two-Layer Material Comprising a Paper Substrate and a Nonwoven Substrate Prepared by an Airlaid Process

[0155] The paper substrate is produced by a wetlaid process. It has a density of 356 mg/cm.sup.3, a thickness of 101 μm and a grammage of 36 g/m.sup.2.

[0156] A web was formed by an airlaid process from softwood fluff pulp. A solution comprising 0.7% solids content of starch (Perfectafilm X115 manufactured by Avebe) is sprayed onto both sides of the web. The sprayed web is then dried by infrared and hot air oven at a temperature of between 180° C. and 190° C.

[0157] The nonwoven substrate obtained comprises 85% by weight of solids of said nonwoven substrate of softwood fluff pulp and 15% by weight of solids of said nonwoven substrate of starch. The nonwoven substrate obtained has a density of 24 mg/cm.sup.3, a thickness of 1910 pm and a grammage of 46 g/m.sup.2.

[0158] The paper substrate was crimped and is then deposited on the nonwoven substrate to produce the two-layer material having a paper substrate:nonwoven substrate mass ratio of 50:50.

Example 1.2

Two-Layer Material Comprising a Paper Substrate and a Nonwoven Substrate Prepared by a Drylaid Process

[0159] The paper substrate is that of Example 1.1.

[0160] A web was prepared by a dry laid process from cottonized flax fibres (VERVAEKE FIBRE NV, 22 mm in length) and lyocell fibres (1.7 dtex/38 mm in length from LENZIG). The cottonized flax fibers and the lyocell fibers were mixed, opened and parallelized with a card before being deposited on a web forming fabric. A solution comprising 5% solids content of starch (Perfectafilm X115 manufactured by AVEBE) is sprayed onto both sides of the web. The sprayed web is then dried by hot air oven at a temperature of between 100° C. and 120° C.

[0161] The nonwoven substrate obtained comprises 92% by weight of solids of said nonwoven substrate of the mixture of cottonized flax fibres and lyocell fibres (90% cottonized flax/10% lyocell by weight of solids of the mixture of fibres) and 8% by weight of solids of said nonwoven substrate of starch. The nonwoven substrate obtained has a density of 12 mg/cm.sup.3, a thickness of 2140 μm and a grammage of 26.2 g/m.sup.2.

[0162] The paper substrate is crimped and is then deposited on the nonwoven substrate to produce the two-layer material having a paper substrate:nonwoven substrate mass ratio of 50:50.

Example 2

Manufacture and Characterization of Filters for a Smoking Article

[0163] Filters for a smoking article were manufactured with the substrates of Examples 1.1 and 1.2 by a standard method for manufacturing filters. A nonporous plug wrap paper was used to wrap the rods of filtering material.

[0164] The filters of the invention were compared with a filter comprising the nonwoven substrate of Example 1.1, with a filter comprising the nonwoven substrate of Example 1.2, with a paper filter and with a commercial cellulose acetate filter.

[0165] The crimped paper filter was made using a standard method for manufacturing filters by crimping the paper substrate of Example 1.1.

[0166] The filters obtained for each term were cut into 21-mm sticks.

[0167] The characteristics of the filters are presented in Table 1 below.

[0168] The resistance to crushing is determined using a DHT 200 instrument from Filtrona. During a measurement, the filter is crushed with a weight of 300 g for 15 seconds. The amount of crushing in millimetres is measured electronically.

TABLE-US-00001 TABLE 1 Filter Filter Filter Filter comprising comprising comprising comprising the two-layer the two-layer the nonwoven the nonwoven Commercial material of material of substrate of substrate of cellulose Crimped paper Example 1-1 Example 1-2 Example 1-1 Example 1-2 acetate filter filter Length of 21 the filters [mm] Diameter of 7.8 the filters [mm] Weight of 194 198 149 148 140 233 the filters [mg] Density of 193 198 146 145 138 238 the filters [mg/cm.sup.3] Crushing 0.40 0.725 0.48 1 Not 0.44 (mm) determined

[0169] According to Table 1, the filters comprising the two-layer material of the invention have a better resistance to crushing than the filters comprising only the nonwoven substrate. This demonstrates that the combination of the paper substrate with the nonwoven substrate obtained by a drylaid process makes it possible to obtain an improvement in the resistance to crushing of the filter comprising only the nonwoven substrate obtained by a drylaid process.

Example 3

Manufacture and Characterization of Cigarettes

[0170] Cigarettes were prepared using the filters described in Example 2. To form the cigarettes, the rods of tobacco were assembled with the filters using tipping paper. A commercial “American blend” tobacco was used to form the rods of tobacco. The cigarettes were prepared with a pressure drop similar to that of the commercial cigarette. The ventilation of the cigarettes was blocked.

[0171] The cigarettes prepared were smoked on a Borgwaldt RM20 smoking machine in accordance with the standard ISO 3308:2000. The pressure drop (“PD” in Table 2) was measured in accordance with the standard 6565:2002. The nicotine content in the smoke was measured in accordance with the standard ISO 10315:2000. The smoking results are presented in Table 2 below.

TABLE-US-00002 TABLE 2 Cigarette with Cigarette with Cigarette with Cigarette with filter filter filter filter comprising comprising comprising comprising the the Cigarette with the two-layer the two-layer nonwoven nonwoven commercial Cigarette with material of material of substrate of substrate of cellulose crimped paper Example 1-1 Example 1-2 Example 1-1 Example 1-2 acetate filter filter Numberof 30 cigarettes smoked PD of the 94 104 101 90 100 100 cigarettes [mmWC] Nicotine retention 51 51 45 45 37 66 [%]

[0172] Table 2 demonstrates that, at an equivalent pressure drop, the nicotine content in the smoke produced by the cigarettes with the filters comprising the two-layer material according to the invention, the cigarettes comprising a commercial cellulose acetate filter and the cigarettes comprising a filter comprising a nonwoven substrate, is of the same order of magnitude. Specifically, the filter of these cigarettes exhibits a nicotine retention of the same order of magnitude.

[0173] Table 2 also demonstrates that, at an equivalent pressure drop, the nicotine content in the smoke produced by the cigarettes comprising the crimped paper filter is much lower than the nicotine content in the smoke produced by the cigarettes comprising a commercial cellulose acetate filter. Specifically, the crimped paper filter exhibits a nicotine retention that is much greater than the commercial cellulose acetate filter.

[0174] This Example 3 thus demonstrates that the user experience provided by the cigarettes comprising the filters comprising the two-layer material according to the invention is close to that provided by cigarettes comprising a commercial cellulose acetate filter.