Composite heat source for a smoking article

Patent metadata

Field	Value
Publication number	US-10440990-B2
Application number	US-201715661884-A
Country	US
Kind code	B2
Filing date	Jul 27, 2017
Priority date	Dec 29, 2011
Publication date	Oct 15, 2019
Grant date	Oct 15, 2019

Abstract

A composite heat source for use in a smoking article is provided, including a non-combustible porous ceramic matrix; and a particulate combustible fuel embedded within the non-combustible porous ceramic matrix. The non-combustible porous ceramic matrix is formed from one or more particulate materials having a median D50 particle size at least five times less than the median D50 particle size of the particulate combustible fuel. Preferably, the non-combustible porous ceramic matrix includes one or more transition metal oxides.

First claim

The invention claimed is:

1. A composite heat source for a smoking article, comprising:
a non-combustible porous ceramic matrix; and
a particulate combustible fuel embedded within the non-combustible porous ceramic matrix,
wherein the non-combustible porous ceramic matrix is formed from one or more particulate materials having a median D50 particle size that is at least five times less than a median D50 particle size of the particulate combustible fuel, and
wherein a volume fraction of the particulate combustible fuel embedded within the non-combustible porous ceramic matrix is less than or equal to about 50% of a bulk volume of the composite heat source.

2. The composite heat source according to claim 1 , wherein the non-combustible porous ceramic matrix comprises one or more oxides.

3. The composite heat source according to claim 2 , wherein the non-combustible porous ceramic matrix comprises one or more transition metal oxides.

4. The composite heat source according to claim 2 , wherein the non-combustible porous ceramic matrix comprises one or more oxides selected from the group consisting of: iron oxide; manganese oxide; zirconia; quartz; and amorphous silica.

5. The composite heat source according to claim 1 , wherein the non-combustible porous ceramic matrix has pores with diameters of between about 0.01 μm and about 10 μm.

6. The composite heat source according to claim 1 , wherein the non-combustible porous ceramic matrix has a thermal diffusivity of less than or equal to about 1×10 −6 m 2 /s.

7. The composite heat source according to claim 1 , wherein the combustible fuel has an oxidation enthalpy of greater than or equal to about 40×10 9 J/m 3 .

8. The composite heat source according to claim 1 , wherein the combustible fuel comprises carbon, aluminium, magnesium, one or more metal carbides, one or more metal nitrides, or a combination thereof.

9. The composite heat source according to claim 1 , further comprising at least one catalyst for the decomposition of a gas produced by combustion of the fuel.

10. The composite heat source according to claim 9 , wherein the at least one catalyst is embedded within the non-combustible porous ceramic matrix.

11. The composite heat source according to claim 1 , further comprising one or more oxidants.

12. The composite heat source according to claim 11 , wherein the one or more oxidants are selected from the group consisting of: nitrates; chlorates; perchlorates; and permanganates.

13. The composite heat source according to claim 1 , further comprising at least one airflow passageway.

14. A smoking article, comprising:
a composite heat source comprising:
a non-combustible porous ceramic matrix; and
particulate combustible fuel embedded within the non-combustible porous ceramic matrix,
wherein the non-combustible porous ceramic matrix is formed from one or more particulate materials having a median D50 particle size that is at least five times less than a median D50 particle size of the particulate combustible fuel, and
wherein a volume fraction of the particulate combustible fuel embedded within the non-combustible porous ceramic matrix is less than or equal to about 50% of a bulk volume of the composite heat source; and

an aerosol-generating substrate.

Assignees

• Philip Morris Products Sa

Inventors

• Raether Friedrich
• Friedrich Holger
• Baber Jens

Classifications

• A24B15/165 Primary

  comprising as heat source a carbon fuel or an oxidized or thermally degraded carbonaceous fuel, e.g. carbohydrates, cellulosic material · CPC title

• C10L5/00

  Solid fuels (produced by solidifying fluid fuels C10L7/00; peat briquettes C10F7/06) · CPC title

• A24B15/16 Primary

  of tobacco substitutes · CPC title

• A24F47/004 Primary

  Human Necessities · mapped topic

• C10L5/02

  {Solid fuels such as} briquettes consisting mainly of carbonaceous materials of mineral {or non-mineral} origin (peat briquettes C10F) · CPC title