Surface modification process

Abstract

Provided is a method for modifying an internal surface of a container or closure, which method comprises contacting the internal surface with a fluorine-containing silane compound to form a modified surface, wherein the container is suitable for storing a medicament.

1 . A method for modifying an internal surface of a container or closure, which method comprises contacting the internal surface with a fluorine-containing silane compound to form a modified surface, wherein the container is suitable for storing a medicament.  
     
     
         2 . A method according to  claim 1 , wherein prior to modifying, the surface to be modified is prepared for modification.  
     
     
         3 . A method according to  claim 2 , wherein preparation comprises cleaning the surface to be modified.  
     
     
         4 . A method according to  claim 2  or  claim 3 , wherein preparation comprises contacting the surface to be modified with hydrochloric acid.  
     
     
         5 . A method according to any preceding claim, wherein after modifying, the modified surface is heated.  
     
     
         6 . A method according to  claim 5 , wherein the modified surface is heated to a temperature of 50-200° C.  
     
     
         7 . A method according to any preceding claim, wherein modifying is carried out at a temperature of 15-100° C.  
     
     
         8 . A method according to any preceding claim, wherein modifying comprises immersing the surface to be modified in a solution of the fluorine-containing silane compound.  
     
     
         9 . A method according to  claim 8 , wherein the immersion is carried out for 10 mins or less.  
     
     
         10 . A method according to any of claims  1 - 7 , wherein modifying comprises applying a plasma coating step to the surface.  
     
     
         11 . A method according to any preceding claim, wherein the modifying is repeated one or more times.  
     
     
         12 . A method according to any preceding claim, wherein the fluorine-containing silane compound comprises a group attached to the silicon atom of the silane, which group is fluorinated at its terminus.  
     
     
         13 . A method according to  claim 12 , wherein the fluorinated terminus comprised in the fluorine-containing group has the formula —(CF 2 ) n CP 3 , wherein n is an integer from 1-20.  
     
     
         14 . A method according to any preceding claim, wherein the fluorine-containing silane compound is a compound of the following formula (I):  
       
         
           
           
               
               
           
         
       
       wherein R 1  comprises a substituted or unsubstituted straight chain or branched hydrocarbon group containing one or more fluorine atoms; and R 2 , R 3  and R 4  are independently substituted or unsubstituted straight chain or branched hydrocarbon groups.  
     
     
         15 . A method according to  claim 14 , wherein R 1  comprises a hydrocarbon group in which the first, second and/or third most distant carbon atom from the silicon atom is (are) substituted entirely by fluorine atoms.  
     
     
         16 . A method according to  claim 14  or  claim 15 , wherein R 1  comprises an alkyl group.  
     
     
         17 . A method according to  claim 16 , wherein R 1  comprises a perfluoroalkyl group.  
     
     
         18 . A method according to any of claims  14 - 17 , wherein R 2  and R 3  independently comprise alkoxy groups or alkanoyloxy groups.  
     
     
         19 . A method according to any of claims  14 - 18 , wherein R 2  and R 3  independently comprise from 1-10 carbon atoms.  
     
     
         20 . A method according to any of claims  14 - 19 , wherein R 4  comprises an alkyl group.  
     
     
         21 . A method according to  claim 20 , wherein R 4  comprises from 1-10 carbon atoms.  
     
     
         22 . A method according to any of claims  14 - 21 , wherein the R 2 , R 3  and OR 4  groups are identical.  
     
     
         23 . A method according to any of claims  14 - 22 , wherein R 1  comprises from 1-20 carbon atoms.  
     
     
         24 . A method according to  claim 12 , wherein the fluorine-containing silane compound is selected from 1H,1H,2H,2H-perfluorooctyltrimethoxysilane (MFS) and 1H,1H,2H,2H-perfluorooctyltrimethoxysilane (EFS).  
     
     
         25 . A method according to any preceding claim, wherein the container comprises a metal canister, or is comprised of a plastics material or a polymer.  
     
     
         26 . A method according to  claim 25 , wherein the container is comprised of a plastics material or a polymer and prior to modifying the surface to be modified is coated with  
     
     
         27 . A method according to  claim 25 , wherein the container is comprised of metal and the metal comprises aluminium or stainless steel.  
     
     
         28 . A method according to any preceding claim, wherein the internal surface subjected to modifying comprises substantially the entire internal surface of the container or closure.  
     
     
         29 . A method for modifying an internal plastics or polymeric surface of a container or closure, which method comprises contacting the internal surface with a fluorine-containing silane compound or a fluorine-containing carbon compound, which silane or carbon compound comprise a group capable of hydrogen bonding to the surface.  
     
     
         30 . A method according to  claim 29 , wherein the group capable of hydrogen bonding to the surface comprises a hydroxy, carboxy and/or amino group.  
     
     
         31 . A method according to  claim 29  or  claim 30 , wherein the fluorine-containing silane compound is a compound of Formula (II):  
       
         
           
           
               
               
           
         
       
       or the fluorine-containing carbon compound is a compound of Formula (III):  
       
         
           
           
               
               
           
         
       
       wherein Z comprises the group capable of hydrogen bonding to the surface, R 1  comprises a substituted or unsubstituted straight chain or branched hydrocarbon group containing one or more fluorine atoms; and R 2  and R 3  are independently substituted or unsubstituted straight chain or branched hydrocarbon groups.  
     
     
         32 . A method according to  claim 31 , wherein R 1  is a group as defined in any of claims  14 - 17  and  23 .  
     
     
         33 . A method according to  claim 31  or  claim 32 , wherein R 2  and/or R 3  are identical to the —CH 2 CH 2 —Z group in Formula (II) or Formula (III).  
     
     
         34 . A method according to any of claims  31 - 33 , wherein the fluorine-containing carbon compound is C 10 F 21 C(CH 2 CH 2 OH) 3  or C 8 F 17 C(CH 2 CH 2 NH 2 ) 3 .  
     
     
         35 . A method for modifying an internal surface of a container or closure formed from a plastics or a polymer material, which method comprises contacting the internal surface with a fluorine-containing carbon compound in a plasma coating step.  
     
     
         36 . A method according to  claim 35 , wherein the fluorine-containing carbon compound is a compound as defined in any of claims  29 - 34 , or is a C 1 -C 10  hydrocarbon compound in which one or more of the hydrogen atoms have been substituted with fluorine atoms.  
     
     
         37 . A method according to  claim 36 , wherein the fluorine-containing carbon compound comprises a compound selected from CF 4 , CHF 3 , CH 2 F 2 , CH 3 F, CH 3 CF 3 , CH 3 CHF 2 , and CH 3 CH 2 F.  
     
     
         38 . A container for storing a medicament, which container is obtainable according to a method as defined in any preceding claim.  
     
     
         39 . A container for storing a medicament, which container comprises a modified internal surface, which surface comprises fluorine-containing hydrocarbon groups chemically bonded to the surface via a silicon-containing group.  
     
     
         40 . A container according to  claim 39 , wherein the fluorine-containing hydrocarbon groups comprise groups R 1  as defined in any of claims  14 - 17 ,  23 ,  31  and  32 .  
     
     
         41 . A container according to any of claims  38 - 40 , which container is comprised of a metal and/or a plastics or polymer material.  
     
     
         42 . A container according to  claim 41 , which container is comprised of aluminium, stainless steel, a polyformaldehyde resin and/or a polybutylene terephthalate.  
     
     
         43 . A system for delivery of a medicament, comprising a container with a modified internal surface as defined in any of claims  38 - 42 .  
     
     
         44 . A system according to  claim 43 , comprising a metered dose inhaler (NMI) or a pressurised metered dose inhaler (pMDI) for delivery of a pulmonary or nasal medicament.