The present invention refers to a container for releasing volatile substances comprising a porous membrane that gets transparent when is in contact with a liquid inside the container.
Membrane based devices for releasing volatile substances in the atmosphere and based on membranes are known for years.
These devices comprise a container, often made by thermoforming, that is closed by the membrane, in order to let the vapor pass through it but not the liquid. On top of the membrane a barrier layer is applied. This barrier layer avoids the substance to go out during the storage and has to be removed by user before a first use.
It is a general need for commercial products to have a clear end of life, in order to communicate the user that the product is exhausted and that a new device need to be used.
The membranes are generally transparent and thus liquid can be seen. But a stronger end of life indication is anyway welcome. In other cases, a porous element is present in the container behind the membrane to act as a wick, feeding with liquid the surface of the membrane and then having maximum evaporation. In such cases, the porous element will hide the liquid and then end of life indication is lost.
Therefore, one purpose of the present invention is to provide a container for releasing volatile substances that permits to show the user that the releasing of the volatile substances is exhausted in a very simply way.
With the container for releasing volatile substances according to the present invention it is possible to solve said drawbacks, providing other advantages that are described below.
The container for releasing volatile substances according to the present invention comprises:
The porous membrane is opaque when it is a dry state, i.e. it is not in contact with a liquid, because the pores diffract the light.
The material of the porous membrane is oleophilic or it has an oleophilic treatment, such as e.g. polypropylene, polyethylene or UHMPWPE.
Furthermore, the membrane has more than 50% (in weight) of capacity of absorbing oil, fragrance, or volatile substances.
The transparency of the porous membrane is obtained when the liquid is inside the pores of the membrane. The porous membrane is not transparent, such as opaque, when the porous membrane is not in contact with the liquid in the container body.
The container according to the present invention can also comprise a barrier layer detachably connected to the porous membrane.
The container for releasing volatile substances according the present invention comprises a message or pattern that is viewed when the porous membrane is transparent.
The message or pattern can be printed on a side of the porous membrane, and/or can be printed on a printed support.
The printed support can be placed between the container body and the porous membrane, or between the porous membrane and the barrier layer.
Advantageously, the container body is transparent.
Preferably, the container body comprises a liquid residue area such as a cavity or a porous element.
For a better understanding the above explanation and for the sole purpose of providing an example, some non-limiting drawings are included that schematically depict a practical embodiment.
The container for releasing volatile substances according to the present invention comprises:
As shown in
A message or a pattern 7 is placed behind the porous membrane 3 and is thus visible only when the membrane is transparent.
In the present application “behind” means on the opposite side of the porous membrane 3 with respect where user can look at it:
The message or pattern 7 can be made by printing the message on the behind face of the porous membrane 3 (embodiment of
In addition, there a is a residue trap, often, even if optimized, fragrances have a non-volatile part (or low volatile, i.e. a part that will evaporate very slowly without having any intensity per se). If nothing is done, this non or low volatile part avoids the porous membrane 3 to turn back to opaque during this zero or low evaporation phase.
To avoid this, a liquid residue containing area can be placed inside the container body 1. This liquid residue area needs to be separated from the porous membrane 3 (not in fluid contact when liquid is almost exhausted).
This liquid residue area can be a cavity 9 (
During the evaporation of the liquid, after the removal of the barrier layer 4, the porous membrane 3 and liquid residue area are in fluid contact as the container body 1 is full of liquid.
As more volatile substances are evaporating first, composition of the liquid is changing with higher concentration of low volatility components. When a certain amount of substance has evaporated, typically more than 90% and ideally more than 95%, the residue will be contained is the liquid residue area and will not penetrate the porous membrane 3.
The volatile substances that are in the porous membrane 3 will thus evaporate completely and porous membrane 3 will turn back to opaque.
In addition, ideally, the porous membrane 3 has a certain capillarity property: in order to have the full porous membrane 1 transparent until end of life, the liquid should be spread in the whole porous membrane 1. For this, it is necessary the capillary rise of the liquid to be at least equivalent to length of the porous membrane 3 in vertical position.
When the container is used for first time, the user must remove the barrier layer 4, permitting the releasing of the volatile substances through the porous membrane 3. As the porous membrane 1 is in contact with the liquid, it is transparent and the user can see the message or pattern 7 (
As the liquid inside the container is wasted, the porous membrane 1 loses progressively its transparency (
Even though reference has been made to a specific embodiment of the invention, it is obvious for a person skilled in the art that the container for releasing volatile substances described herein is susceptible to numerous variations and modifications, and that all of the details mentioned can be substituted for other technically equivalent ones without departing from the scope of protection defined by the attached claims.
Number | Date | Country | Kind |
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20217394.4 | Dec 2020 | EP | regional |
Number | Date | Country | |
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Parent | PCT/EP21/87473 | Dec 2021 | US |
Child | 18343472 | US |