Method for treating the surface of a device for dispensing a fluid product

Abstract

A treatment method for treating the surface of a fluid dispenser device, said method comprising the step of using chemical grafting to form a thin film on at least one support surface of at least one movable portion of said device that is movable while said device is being actuated, said thin film having anti-friction properties.

1 . A treatment method for treating the surface of a fluid dispenser device, said method being characterized in that it comprises a step of using chemical grafting to form a thin film on at least one support surface of at least one movable portion of said device that is movable while said device is being actuated, said thin film having anti-friction properties. 
     
     
         2 . A method according to  claim 1 , wherein said grafting step comprises putting said surface that is in contact with the fluid into contact with a solution that includes at least one adhesive primer, said adhesive primer being a cleavable aryl salt, and at least one monomer or polymer selected from the group constituted by vinyl- or acrylic-terminated siloxanes. 
     
     
         3 . A method according to  claim 1 , wherein vinyl- or acrylic-terminated siloxanes are selected from the group constituted by: vinyl- or acrylic-terminated polyalkylsiloxanes such as vinyl- or acrylic-terminated polymethylsiloxane; vinyl- or acrylic-terminated polydimethylsiloxane such as polydimethylsiloxane-acrylate (PDMS-acrylate); vinyl- or acrylic-terminated polyarylsiloxanes such as vinyl- or acrylic-terminated polyphenylsiloxane such as polyvinylphenylsiloxane; and vinyl- or acrylic-terminated polyarylalkylsiloxanes such as vinyl- or acrylic-terminated polymethylphenylsiloxane. 
     
     
         4 . A method according to  claim 1 , wherein the cleavable aryl salt is selected from the group constituted by: aryl diazonium salts; aryl ammonium salts; aryl phosphonium salts; aryl sulfonium salts; and aryl iodonium salts. 
     
     
         5 . A method according to  claim 1 , wherein said chemical-grafting step is initiated by chemical activation. 
     
     
         6 . A method according to  claim 5 , wherein said chemical activation is initiated by the presence of a reducing agent in the solution. 
     
     
         7 . A method according to  claim 6 , wherein the reducing agent is selected from the group constituted by: reducing metals that are possibly finely divided, such as iron, zinc, or nickel; a metal salt that is possibly in the form of a metallocene; and an organic reducing agent such as hypophosphorus acid, or ascorbic acid. 
     
     
         8 . A method according to  claim 1 , wherein a potential difference is applied in said solution. 
     
     
         9 . A method according to  claim 8 , wherein the potential difference is applied by a generator that is connected to two electrodes that are identical or different and that are dipped in the solution. 
     
     
         10 . A method according to  claim 8 , wherein the potential difference is generated by a chemical cell. 
     
     
         11 . A method according to  claim 1 , wherein said support surface is made of: synthetic material, in particular comprising polyethylene and/or polypropylene; elastomer; glass; or metal. 
     
     
         12 . A method according to  claim 1 , wherein said thin film has a thickness that is less than 1 μm, preferably lying in the range 10 Å to 2000 Å. 
     
     
         13 . A method according to  claim 1 , wherein the method further comprises the step of using chemical grafting to form at least one additional thin film on said support surface. 
     
     
         14 . A method according to  claim 13 , wherein the method further comprises the step of using chemical grafting to form a first additional thin film on said support surface, said first additional thin film limiting the degree to which the fluid for dispensing sticks to said support surface. 
     
     
         15 . A method according to  claim 13 , wherein the method further comprises the step of using chemical grafting to form a second additional thin film on said support surface, said second additional thin film preventing interactions between said support surface and said fluid. 
     
     
         16 . A method according to  claim 13 , wherein said at least one additional thin film is deposited on said support surface during at least one successive chemical-grafting step, each step being performed in a single-component bath. 
     
     
         17 . A method according to  claim 13 , wherein said at least one additional thin film is deposited on said support surface simultaneously during a single chemical-grafting step in a multi-component bath. 
     
     
         18 . A method according to  claim 1 , wherein said dispenser device comprises: a reservoir containing the fluid; a dispenser member, such as a pump or a valve, that is fastened on said reservoir; and a dispenser head that is provided with a dispenser orifice, and this is for actuating said dispenser member. 
     
     
         19 . A method according to  claim 1 , wherein said dispenser device comprises: a plurality of individual reservoirs each containing a dose of fluid; reservoir opening means, such as a perforator needle; and dose dispenser means for dispensing a dose of fluid from an individual opened reservoir through a dispenser orifice. 
     
     
         20 . A method according to  claim 1 , wherein said dispenser device includes a reservoir containing one or two doses of fluid, and a piston that moves in said reservoir on each actuation. 
     
     
         21 . A method according to  claim 1 , wherein said dispenser device includes a dose counter for counting the number of doses that have been dispensed or that remain to be dispensed from said dispenser device. 
     
     
         22 . A method according to  claim 1 , wherein said fluid is a liquid or powder pharmaceutical, in particular for spraying in nasal or oral manner. 
     
     
         23 . The use of a grafting method according to  claim 1 , in order to form a thin film on at least one support surface of at least one movable portion of a fluid dispenser device that is movable while said device is being actuated, said thin film having anti-friction properties.