Cigarette Paper Having a High Diffusion Capacity During Thermal Decomposition

Abstract

The invention relates to cigarette paper which contains a water-soluble salt, preferably sodium bicarbonate, potassium bicarbonate or ammonium carbonate, as a result of which a high diffusion capacity during thermal decomposition, and thus a reduction in harmful carbon monoxide in the cigarette smoke, is achieved. The invention relates in particular to cigarette paper comprising at least one water-soluble salt which has lost more than 15% of its initial mass after heating to 230° C. The invention further relates to a cigarette produced from the cigarette paper, to a method for producing the cigarette paper and to the use of the water-soluble salt.

We claim: 
     
         1 . A cigarette paper for wrapping the tobacco rod of a cigarette, which cigarette paper comprises at least one water-soluble salt, wherein the water-soluble salt is a salt which after heating to 230° C. has lost more than 15% of its initial mass when the heating, starting at a temperature of 30° C., is carried out at a heating rate of 5° C./min under a nitrogen flow of 25 ml/min. 
     
     
         2 . The cigarette paper of  claim 1 , wherein said water-soluble salt is a salt which after heating to 230° C. has lost more than 25% of its initial mass when the heating, starting at a temperature of 30° C., is carried out at a heating rate of 5° C./min under a nitrogen flow of 25 ml/min. 
     
     
         3 . The cigarette paper according to  claim 1 , wherein the water-soluble salt is a bicarbonate. 
     
     
         4 . The cigarette paper of  claim 3 , wherein the water-soluble salt is a salt selected from a group of an alkali metal bicarbonate, an ammonium bicarbonate, and an ammonium carbonate. 
     
     
         5 . The cigarette paper according to  claim 4 , wherein the alkali metal bicarbonate is one of a sodium or a potassium bicarbonate. 
     
     
         6 . The cigarette paper according to  claim 1 , wherein the quantity of the water-soluble salt is 0.1% to 10% of the paper mass. 
     
     
         7 . The cigarette paper according to  claim 1 , wherein the quantity of the water-soluble salt is 1% to 6%, of the paper mass. 
     
     
         8 . The cigarette paper according to  claim 1 , wherein the quantity of the water-soluble salt is 3% to 6% of the paper mass. 
     
     
         9 . The cigarette paper according to  claim 1 , wherein the water-soluble salt is present in discrete areas. 
     
     
         10 . The cigarette paper according to  claim 9 , wherein said discrete areas are stripe-shaped areas. 
     
     
         11 . The cigarette paper according to  claim 10 , wherein the areas are designed such that they form one or more bands in the circumferential direction of a tobacco rod of a cigarette manufactured from the cigarette paper. 
     
     
         12 . The cigarette paper according to one of  claim 1 , wherein the cigarette paper is impregnated with the at least one water-soluble salt. 
     
     
         13 . The cigarette paper according to one of  claim 1 , wherein the cigarette paper is coated on one or both sides with the at least one water-soluble salt. 
     
     
         14 . A cigarette comprising the cigarette paper, said paper including at least one water-soluble bicarbonate. 
     
     
         15 . A process for manufacturing a cigarette paper, which method comprises the following steps:
 (1) providing a cigarette paper or a fibre-filler suspension with less than 50% water content with respect to the total paper mass or the total mass of the fibre-filler suspension respectively, and   (2) applying an aqueous solution with at least one water-soluble salt to the cigarette paper or the fibre-filler suspension passing through the paper machine respectively, whereby the quantity of water-soluble salt in the solution is 0.2% to 20% with respect to the mass of the solution, wherein said water-soluble salt is a salt which after heating to 230° C. has lost more than 15% of its initial mass when the heating, starting at a temperature of 30° C., is carried out at a heating rate of 5° C./min under a nitrogen flow of 25 ml/min.   
     
     
         16 . The process of  claim 15 , wherein the fibre-filler suspension has a water content of less than 30% with respect to the total paper mass or the total mass of the fibre-filler suspension respectively. 
     
     
         17 . The process of  claim 15 , wherein the quantity of water-soluble salt in the solution is 2% to 15%, with respect to the mass of the solution. 
     
     
         18 . The process according to  claim 15 , wherein the water-soluble salt is a bicarbonate. 
     
     
         19 . The process according to  claim 18 , wherein the water-soluble is a salt selected from a group of an alkali metal bicarbonate, an ammonium bicarbonate, and an ammonium carbonate. 
     
     
         20 . The process according to  claim 19 , wherein the alkali metal bicarbonate is one of a sodium- or a potassium bicarbonate. 
     
     
         21 . The process according to  claim 15 , wherein the aqueous solution is applied using a size press or a film press. 
     
     
         22 . The process according to  claim 15 , wherein the aqueous solution is applied using a printing or spraying technique. 
     
     
         23 . Use of at least one water-soluble salt to increase the diffusion capacity of a cigarette paper, or of areas of a cigarette paper for wrapping the tobacco rod of a cigarette, during thermal decomposition by more than 0.9 cm/s or by more than 50% based on the initial value of the diffusion capacity at 23° C. before the thermal degradation. 
     
     
         24 . Use according to  claim 23 , wherein the water-soluble salt is a bicarbonate. 
     
     
         25 . Use according to  claim 24 , wherein the water soluble salt is a salt selected from a group of an alkali metal bicarbonate, an ammonium bicarbonate, and an ammonium carbonate. 
     
     
         26 . Use according to  claim 25 , wherein the alkali metal bicarbonate is one of a sodium or a potassium bicarbonate. 
     
     
         27 . A cigarette paper for wrapping the tobacco rod of a cigarette, said cigarette paper comprising at least one water-soluble salt, wherein the water-soluble salt is a bicarbonate. 
     
     
         28 . A cigarette paper according to  claim 27 , wherein said water-soluble salt is a salt selected from a group of an alkali metal bicarbonate, an ammonium bicarbonate, and an ammonium carbonate. 
     
     
         29 . A cigarette paper according to  claim 28 , wherein said alkali metal bicarbonate is one of a sodium or a potassium bicarbonate.