Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65B—MACHINES, APPARATUS OR DEVICES FOR, OR METHODS OF, PACKAGING ARTICLES OR MATERIALS; UNPACKING
  • B65B31/00—Packaging articles or materials under special atmospheric or gaseous conditions; Adding propellants to aerosol containers
  • B65B31/003—Adding propellants in fluid form to aerosol containers

Definitions

• the present invention relates to a method of removing air from containers which are to be filled with a substance to be dispensed and with a propellant. This removal of air is generally known as "purging" and will be so- described in this application.
• the invention particularly concerns a method of purging containers which are to be filled with a suspension or solution of a substance, for example a pharmaceutical material, in a propellant which is gaseous at room temperature but is held under pressure in liquid form.
• a propellant is known as a high- pressure propellant.
• This type of filling method is described in UK Patent Publication No. 2236146. In this filling method, after the suspension is filled into the container, an amount of high pressure propellant without the pharmaceutical material therein is forced through the filling head, thereby cleaning the filling head and ensuring that when the filling head is lifted no suspension can escape into the atmosphere. The filling is conducted through the outlet valve of the container, because high pressure propellents are involved.
• US Patent 2684806 discloses a purging method comprising the steps of partially filling the open containers with the soap solution and then introducing into the soap solution a gas which expands the solution into a foam until it fills the container. The valve is then sealed onto the container and the volatile propellant is introduced through the valve.
• the equivalent of the soap solution would be the suspension of pharmaceutical material in a high pressure propellant. Unlike the soap solution, this is volatile and in any case it is highly undesirable to have the pharmaceutical material in open contact with the atmosphere. Even if high pressure propellant alone were put into the open container, this would evaporate over time; even if the container were closed quickly, movement of the container to the valve fitting station would cause air turbulence and the container would tend to entrain air into it.
• a method of purging a container which is to be filled with a substance to be dispensed and a high- pressure propellant comprising the steps of: placing a valve on the container without sealing it thereon; introducing an amount of high-pressure propellant into the container; allowing the high-pressure propellant to expand and force air in the container out through the unsealed connection between the valve and the container; and sealing the valve onto the container.
• the invention also provides an aerosol dispenser comprising a container and a valve sealed to the container, wherein the container is purged and filled by a method comprising the steps of: placing a valve on the container without sealing it thereon; introducing an amount of high-pressure propellant into the container; allowing the high pressure propellant to expand and force air in the container out through the unsealed connection between the valve and the container; sealing the valve on to the container; and introducing the substance to be dispensed and a further quantity of high- pressure propellant into the container through the valve after the valve has been sealed on to the container.
• valve loose on the container allows the evaporating high-pressure propellant to expel air out around the valve while not allowing air back in.
• high-pressure propellant is most advantageously filled into the container through the valve.
• the open container can be partly filled with a substance in a low-pressure propellant (i.e. one which is liquid at room temperature).
• a low-pressure propellant i.e. one which is liquid at room temperature.
• the valve can then be placed on the container and the air purged as described above, before sealing the valve and then introducing the final amount of high- pressure propellant through the valve.
• FIG. 1 shows, schematically, a purging method according to the invention.
• the drawing indicates three successive stations A, B and C of a purging and filling process.
• station A an empty container 1 has a valve 2 simply placed thereon; the valve is not sealed onto the container, so that a limited air gap is left around the top of the container.
• a filling head 3 is lowered onto the container 1 and an amount of high-pressure propellant is injected into the container.
• the amount may be, for example, 0.2g of liquid propellant.
• the filling head 3 is not described in detail since its construction will be well understood by those skilled in the art; the filling head is equivalent to a standard gassing head with an integral metering system.
• the propellant drops to the bottom of the container and evaporates, displacing air out of the container. In practice the propellant will be heavier than air and so displaces the air from the bottom of the container upwards.
• the filling head should be lifted slowly off the valve, for example at a velocity of 20cm/s. After the head is lifted off the valve, it can be retracted at a higher velocity.
• valve is crimped onto the container by a crimping head 4, in a conventional fashion.
• the sealed container can now be moved to a filling station at which it can be filled through the valve with a suspension of pharmaceutical substance in a high-pressure propellant followed, optionally, by propellant alone to clean the filling head.
• the pharmaceutical substance can be, for example, salbutamol, beclomethasone dipropionate, salmeterol or fluticasone propionate.
• the purging propellant can be the same as the filling propellant, for example 1,1,1,2-tetrafluoroethane, i.e. propellant 134a.
• the purging method described has been found to be extremely efficient, because the valve is in place while purging occurs, loss of the propellant and entrainment of air is avoided and, in addition, the air in the valve itself is purged.

Landscapes

• Chemical & Material Sciences (AREA)
• Dispersion Chemistry (AREA)
• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Vacuum Packaging (AREA)
• Containers And Packaging Bodies Having A Special Means To Remove Contents (AREA)
• Colloid Chemistry (AREA)
• Feeding, Discharge, Calcimining, Fusing, And Gas-Generation Devices (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=10732789

Family Applications (1)

Country Status (17)

Families Citing this family (8)

Family Cites Families (4)

• 1993
  • 1993-03-26 GB GB939306292A patent/GB9306292D0/en active Pending
• 1994
  • 1994-03-24 EP EP94912517A patent/EP0689515A1/en not_active Withdrawn
  • 1994-03-24 CZ CZ952172A patent/CZ217295A3/cs unknown
  • 1994-03-24 CA CA002158070A patent/CA2158070A1/en not_active Abandoned
  • 1994-03-24 SK SK1199-95A patent/SK119995A3/sk unknown
  • 1994-03-24 JP JP6521642A patent/JPH08508226A/ja active Pending
  • 1994-03-24 BR BR9406027A patent/BR9406027A/pt not_active Application Discontinuation
  • 1994-03-24 AU AU65045/94A patent/AU6504594A/en not_active Abandoned
  • 1994-03-24 HU HU9502513A patent/HU9502513D0/hu unknown
  • 1994-03-24 ZA ZA942071A patent/ZA942071B/xx unknown
  • 1994-03-24 WO PCT/EP1994/000921 patent/WO1994022722A1/en not_active Application Discontinuation
  • 1994-03-24 PL PL94310808A patent/PL310808A1/xx unknown
  • 1994-03-24 SI SI9420010A patent/SI9420010A/sl unknown
  • 1994-03-24 CN CN94191450A patent/CN1119008A/zh active Pending
  • 1994-03-25 IL IL10913794A patent/IL109137A0/xx unknown
• 1995
  • 1995-09-22 FI FI954495A patent/FI954495A/fi unknown
  • 1995-09-25 NO NO953793A patent/NO953793L/no unknown

Non-Patent Citations (1)

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