Dispensing – With filter – Associated with vent passage
Reexamination Certificate
1999-10-28
2001-06-12
Kaufman, Joseph A. (Department: 3754)
Dispensing
With filter
Associated with vent passage
C222S189110
Reexamination Certificate
active
06244472
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a dispenser for substances packaged in liquid form, and more particularly intended for cosmetic, dermatological, pharmaceutical, ophthalmic, or perfumery applications. More particularly, the invention relates to a dispenser comprising a flask or tank for the substance, and a closure member having an end valve and/or a pump with an endpiece, in which the surfaces that come into contact with the active principle are designed so as to filter and treat the air that penetrates into the inside of the tank.
2. Description of the Related Art
In conventional manner, four embodiments are known that serve to guarantee that the substance contained inside the tank of a dispenser remains sterile.
In a first embodiment, the substance is packaged in a deformable, flexible bag that forms the tank and that is connected to a pump that has no air intake, commonly referred to as an “airless” pump. The pump is fixed to a rigid flask, thereby holding the flexible bag captive inside the flask. As substance is taken by the user acting on the pump, so the bag shrinks, reducing its capacity by a volume that is equivalent to the volume that has been taken out, and thus leading to the tank becoming deformed.
The drawbacks of that particular embodiment lie firstly in the presence of two packages (the bag and the flask) which increases manufacturing cost, and secondly in the unfavorable ratio between usable volume and total volume. In addition, filling and packaging operations are difficult, in particular for substances that are in the form of creams.
In a second embodiment, the substance is packaged in a cylindrical flask whose bottom is provided with a moving follower piston. As the substance is taken out via an “airless” pump, so the piston rises in the flask, thereby reducing the capacity of the flask by a volume equivalent to the volume taken out.
The drawbacks of that embodiment lie mainly in the cost of the packaging, and in its unsuitability for dispensing a liquid.
In a third embodiment, specifically intended for dispensing liquids, an “airless” pump is connected to a flask which is made of glass and which is therefore not deformable. Such “airless” pumps are capable of operating when the pressure inside the flask is at 0.5 bars, and of still ensuring that doses are regular.
The glass flasks are thus filled with a liquid to 50% relative to the total volume of the flask so as to guarantee that the pressure threshold of 0.5 bars is not reached until the flask has been emptied.
The major drawback of that embodiment lies in the unfavorable ratio between the usable volume and the total volume, and thus in the extra cost generated by the volume of the packaging.
In the fourth known embodiment, constituting the subject matter of French patent application No. 2 740 431 in the name of the same Applicant, an “airless” pump is used that is connected to a flask of a plastics material whose walls are permeable to air.
The drawback of that embodiment lies in the fact that the air passes through the wall of the flask and then through the liquid, which has the effect of slowing down the rate at which air diffuses and the speed at which the extracted dose is replaced.
If the dispenser is used intensively and rapidly, then suction builds up inside the flask and can run the risk of exceeding the operating limit of the pump.
SUMMARY OF THE INVENTION
The present invention seeks to solve all of the technical problems associated with the above-described embodiments, by proposing a system for filtering and treating the intake air flow, thus avoiding the need to use so-called “airless” preservation systems by proposing to use filtered air that is free from bacteria and/or that has a modified oxygen content. The dispenser, which is not restricted to liquids and to creams, makes it possible to fill 90% to 95% of the total volume of the tank.
According to the invention, the dispenser comprises a dispenser for substances packaged in the form of a liquid, cream, or gel, and particularly intended for cosmetic, dermatological, pharmaceutical, ophthalmic, or perfumery applications, the dispenser being of the type comprising a tank of substance connected at one of its ends to a head provided with a pump fitted with a fixing collar and with controlled shutter means for the vent formed on the body of said pump, the device being characterized in that said shutter means comprises an air-permeable diffuser element containing non-migratory agents for bacteriological and/or chemical treatment of air by contact; said element being engaged on the pump body and being held by leakproof peripheral radial clamping of at least one annular zone, and by its top portion being engaged in the fixing collar.
In a first embodiment, the diffuser element is a filter-forming porous core of annular section which is engaged directly on the pump body and which has pores of a size lying in the range 5 &mgr;m to 10 &mgr;m.
Preferably, the mean pore size of the diffuser element is substantially equal to 7 &mgr;m, with an empty fraction lying in the range 40% to 60%.
In a second embodiment, the diffuser element is an elastically deformable sleeve defining a flexible pocket of variable volume around the pump body and whose membrane-forming wall is made out of a material that has intrinsic permeability to air lying in the range 300 mm
3
/24 h to 5000 mm
3
/24 h.
In a variant, said material also contains porous fillers.
According to an advantageous characteristic, the material constituting the diffuser element contains anti-oxidizing, bactericidal, antiseptic, and/or atmosphere-modifying treatment agents, in independent or combined form.
The diffuser element used in the dispenser of the invention does not constitute a physical barrier preventing the passage of bacteria as in prior art dispensers, but forms either a filter or a membrane providing a large exchange area for incoming air to enable it to be subjected to bacteriological and/or chemical treatment by coming into contact with nonmigratory agents inside the element.
In addition, both the dimensions of the filter pores and the selective permeability of the membrane combined with the surface tension properties of the materials used, serve to prevent liquids from passing through, thus making the diffuser element hydrophobic and making it possible to prevent bacteria from proliferating inside the tank.
Other characteristics and advantages of the present invention appear from the following description given with reference to the accompanying drawings which show embodiments that are not limiting in any way.
REFERENCES:
patent: 4093124 (1978-06-01), Morane et al.
patent: 4533068 (1985-08-01), Meierhoefer
patent: 4694976 (1987-09-01), Schuetz
patent: 4917271 (1990-04-01), Kanner et al.
patent: 6053368 (2000-04-01), Geimer
Bacon & Thomas PLLC
Deal David
Kaufman Joseph A.
Sofab
LandOfFree
Dispenser for liquid, cream or gel with a filter does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Dispenser for liquid, cream or gel with a filter, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Dispenser for liquid, cream or gel with a filter will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2500939