440 



4,236,532 



8 



2. A method according to claim 1, wherein the addi- 

 tive comprises a stable nicotine salt. 



3. A method according to claim 2, in which the stable 

 nicotine salt is nicotine tartrate or nicotine hydrogen 

 tartrate. ' 



4. A method according to claim 1, in which the ink 

 contains a component the presence of which promotes 

 the transfer of the additive into the main stream smoke 



5. A method according to claim 4, wherein the com- 

 ponent is a dirrerenl one of the additives. 



6. A method according to claim 4, in which the addi- 

 tive is a stable nicotine salt and the component has an 

 affmity for free base nicotine. 



7 A method according to claim 6, in which the com- 

 ponent is docosene. 



8. A method according to claim 1, wherein two dif- 

 ferent additives are incorporated in the same ink. 



9. A method according to claim 1, wherein two addi- 

 tives are separately incorporated in dilTerent inks which ^g 

 are printed on the wrapper in two different series of 

 dots. 



10. A method according to claim 1, wherein the ink 

 contains a hydrophilic vehicle. 



11. A method according to claim 10, in which the 25 

 hydrophilic vehicle is one. or a mixture, of water, ethyl 

 alcohol, and isopropyl alcohol. 



12. A method according to claim 1, in which the ink 

 contains a filler. 



13. A method according to claim 12, in which the 30 

 filler is calcium carbonate, titanium dioxide, silicon 

 dioxide or a silicate such as Bentonite. 



14 A method according to claim 1, wherein the ink 

 contains a thickening agent. 



15. A method according to claim 14, in which the 33 

 thickening agent is carboxymethyl cellulose, poly- 

 melhyl hydroxy cellulose, polyethyl hydroxy cellulose, 

 or hydroxy propyl cellulose. 



Iti. A method according to claim 1, wherein the addi- 

 tive is concentrated at that end of the wrapper which is 

 tc be at the lit end of the smoking rod 



17. A method according to claim 16, wherein the 

 additive concentration is determined by varying the dot 

 size or dot height 



18. A method according to claim 16, wherein the 

 additive concentration is determined by controlling the 

 dot density. 



19. A method according to claim 16, wherein the 

 additive concentration is determined by controlling the 

 area of the wrapper surface which is printed. 



20. The product produced by the process of claim 1. 



21. A method of producing a wrapper for a smoking 

 rod, the method comprising screen printing onto the 

 surface of the wrapper, a series of discrete dots of an ink 

 containing a hydrophilic vehicle, a thickening agent, a 

 filler, and a stable nicotine salt, the printing extending 

 over a selected area of the wrapper to provide a greater 

 deposition of the ink adjacent to that end of the wrapper 

 which will be the lit end in use. 



22. A smoking rod of the kind comprising a filler of 

 smoking material surrounded by a combustible tubular 

 wrapper, the improvement wherein the filler is up- 

 graded by the provision on the inner surface of the 

 wrapper of a screen printed deposition of a series of 

 discrete dots of an ink containing at least one additive 

 selected from the group consisting of a smoke produc- 

 ing agent, a smoke nucleation agent, a flavouring agent, 

 and a physiologically active agent, which will in use, 

 upon approach of the hot burning tip of the smoking 

 rod, be transferred and contribute to the main stream 

 smoke drawn through the rod to enhance the satisfac- 

 tion to the smoker, wherein the dots are printed over a 

 selected area of the wrapper to provide a greater con- 

 centration of the additive at that end of the rod to be the 

 lit end of the rod. 



40 



S3 



60 



6S 



