FR2843043A1 - Simple and cheap device for absorbing humidity in a controlled manner using a pouch made of two materials and containing an adsorbant - Google Patents

Abstract

Device for absorbing humidity made of an absorbant of humidity (6) and a wall with a first area (2) and a second area (3). The first area of the wall is impermeable to liquids but permeable to humidity and the second area of the wall is impermeable to liquids. The wall defines a volume impermeable to liquids and containing the absorbant of humidity The first area of the wall defines a first chamber (2c) and is in communication with the second area which defines a second chamber (3c). The second chamber is intended to recover the liquid from the absorbant after absorption. The first area is made of a non-woven and/or untearable material, preferably based on high density polyethylene fibres, in particular TYVEK. The second area is made of an extruded or coextruded laminate, preferably based on polyethylene. A pouch (5) is placed in the volume defined by the wall. This pouch is permeable to liquids and to humidity and contains the absorbant. The pouch is of non- woven material, or made from an extruded or coextruded laminar film, preferably a micro- perforated polyethylene. The absorbant is chosen from chlorine-based absorbants, in particular magnesium, sodium or calcium chloride or a mixture thereof, preferably magnesium chloride. The second region is protected from the humid air by a pealable film. The device also includes a support for active substances selected from bactericides, deodorants, anti-rust agents, coloured indicators to indicate the air humidity, or to visualise the degree of saturation of the adsorbant. In particular, the first area is made from TYVEK and the second area from polyethylene. The pouch is made of micro-perforated polyethylene and the absorbant is magnesium chloride. The peelable film is polyethylene.

Description

WATERPROOF DEVICE FOR MOISTURE ABSORPTION

  The present invention relates to a sealed device for absorbing moisture. In the present application, by humidity is meant the

water vapor in the air.

  The presence of moisture in the ambient air is often undesirable. This is particularly the case in certain regions where climatic conditions induce

  high humidity percentages in the air.

  When these percentages are high, humidity can damage the integrity of dwellings or objects therein by inducing a number of phenomena, in particular paint cracking or cracking, peeling or yellowing of the wallpaper, mold , halos, saltpetre formation,

  rust, swelling and crackling woodwork.

  Humidity also poses many problems for electronics manufacturers whose products are

  particularly sensitive to such degradation.

  Moisture problems are also particularly monitored in the food sector, since they are likely to act on the expiration of food products, which represents a significant risk of product loss or, worse, poisoning of the consumer. Recent studies have also shown that humidity is an aggravating factor for many human diseases, including

asthma.

  Attempts have been made to solve these humidity problems by proposing devices absorbing humidity to be placed in humid environments. Such devices generally have two communicating chambers. The first chamber contains a moisture absorbent and an opening. It is indeed necessary to arrange an opening in the device for bringing the humid air into contact with the absorbent. Once absorption has taken place, the absorbed water vapor forms a liquid in association with the absorbent. This liquid is collected in

the second bedroom.

  Devices of this type are described in particular in patent applications WO 93/14996, WO 95/26914, WO 97/43193 and WO 99/61345. In these devices, an opening is provided in the first chamber. This opening is protected by a grid and allows moist air to be absorbed. Although these devices are closed, they are not waterproof and the liquid resulting from absorption can spread into the environment through the protective grid and degrade it. This is all the more annoying that these devices are precisely used to preserve an environment from degradation. Finally, due to their complex structure, these devices are particularly difficult to

manufacture.

  The operation of absorbent devices requires at least one opening for bringing the air into contact

wet with the absorbent.

  However, the Applicants have succeeded in developing a completely waterproof device, that is to say, the operation of which does not precisely require having an opening for bringing moist air into contact with the absorbent. . The device according to the invention thus has both the advantage of being completely impermeable to liquids and that of avoiding any risk of

environmental contamination.

  One of the objectives of the invention is therefore to provide a waterproof moisture-absorbing device, simple to manufacture and solid, presenting no risk of contamination of the environment by the absorbent or the recovered liquid. By sealed device is meant, in the present application, a device impermeable to liquids under normal conditions of temperature and pressure. The device (1) for absorbing moisture according to the invention comprises a moisture absorbent (6), a wall comprising a first region (2) and a second region (3), said device being characterized by fact that: the first region (2) of the wall is impermeable to liquids but permeable to moisture; - The second region (3) of the wall is impermeable to liquids; said wall defining a volume impermeable to

  liquids and containing the absorbent of humidity (6).

  In practice, the moisture absorbent (6), which is contained in the liquid-impermeable volume defined by the first and second regions (2), (3), absorbs moisture through the first region which is permeable to moisture. Once absorbed by the absorbent (6) inside the device (1), the humidity gives a solution with said moisture absorbent (6). This solution is held captive inside the device (1) since the entire wall of the device which includes the regions (2) and (3) is impermeable to liquids. As a result, the

  solution cannot contaminate the environment.

  For the purposes of the present invention, the term “absorbent (6) or absorbent of moisture (6) means any

  substance capable of producing moisture absorption.

  Absorption is defined as the action of said substance to fix a liquid or a gas. These definitions are in accordance with those given in the "Dictionary of chemistry and its applications", 3rd

edition, C. and R.DUVAL.

  In the context of the present invention, it is possible to use any absorbent material known to a person skilled in the art for its moisture absorption properties. Preferably, these materials are chosen from the group consisting of chloride-based substances, in particular calcium chloride, magnesium chloride, sodium chloride or their mixtures. Preferably, the moisture absorbent (6) is concentrated magnesium chloride, for example 96%. This magnesium chloride can in particular be in the form of

glitter or beads.

  This absorbent (6) is preferably contained in a pocket (5), placed inside the volume defined by the wall comprising the regions (2) and (3). This pocket (5) is made from any material known to those skilled in the art for its properties of permeability to liquids and to humidity. The pocket (5) can in particular be made of nonwoven material or a micro-perforated film, preferably a film of extruded or coextruded micro-perforated material, and more preferably still of micro-perforated polyethylene. In the present application, by pocket (5) is meant a

  closed volume, delimited by a flexible or rigid wall.

  This wall can be micro-perforated with perforations

  (5P) or not to let the liquids pass.

  This pocket (5) can have any dimension or shape allowing its positioning in the impermeable volume defined by the wall comprising the regions (2), (3). Preferably, the pocket (5) is fixed to the wall of the device (1). More preferably, the pocket (5) is fixed to the wall at the height of the region (2) which is permeable to moisture. In particular, it can be

  fixed by ultrasonic, thermal or adhesive welding.

  To make this first region (2) of the device (1), any material known to those skilled in the art can be used for its properties of impermeability to liquids and permeability to moisture in

  normal temperature and pressure conditions.

  The first region (2) can thus in particular be produced, at least in part, from a non-woven and / or tear-resistant material (4), preferably based on high density polyethylene filaments and more preferably based on TYVEK brand material (DUPONT DE NEMOURS). The term “tear-resistant material” means a material which cannot be torn by hand. The preferred TYVEK is the TYVEK 1073B marketed by the

Dupont de Nemours company.

  This first region (2) can have any shape and dimension. This shape can in particular be square or rectangular. Preferably, the first region (2) defines a first chamber (2c) in the form of a rectangular envelope closed on three of its four sides and in communication with the second region (3) on its open side. Likewise, the second region (3) can be produced from any material known to those skilled in the art for its properties of impermeability to liquids under normal conditions of temperature and pressure. The second region (3) is in particular a film of extruded or coextruded material, preferably a polyethylene film. Like the first region (2), the second region (3) can have any shape or size. This shape can in particular be square or rectangular. Preferably, the second region (3) defines a second chamber (3c) in the form of a rectangular envelope closed on three of its four sides and in communication with the

  first bedroom on its open side.

  The assembly of the first and second regions (2), (3) can be carried out by any means known to those skilled in the art and ensuring the tightness of the volume defined by

  the assembly of these first and second regions (2), (3).

  One can use in particular thermal welding, ultrasonic welding or bonding. It is also possible that the first and second regions (2), (3) are assembled and brought into communication by screwing or clipping. In this case, the two regions (2), (3) can be easily separated for recycling on the one hand from the first region (2) and on the other hand from the second region (3). In order to preserve all of its absorbent qualities to the device before its use, it is advantageous to protect the first region (2) from moist air over its entire surface by means of a protective film (8), preferably peelable. By peelable is meant a film reversibly attached to the first region (2), for example by means of an adhesive film. In other words, this film is easily removable without causing damage to the first region (2). The material of this protective film (8) is of course impermeable to moisture. Suitable peelable materials are for example laminated, extruded materials such as polyethylene or coextruded materials such as polyamide / polyethylene or polyester / polyamide

  or a laminate of paper / polyethylene.

  The protective film (8) is removed to put the device into service. Once the film has been removed, the first region (2) is in contact with moist air. The water vapor contained in the humid air will be absorbed by the absorbent (6) by passing through the moisture-permeable material of the first region (2), then through the moisture-permeable material and liquids

pocket (5).

  In certain applications of the device (1), it may be advantageous to further provide a support for active substances. These active substances are used in particular to indicate the degree of humidity or to diffuse a bactericide. Suitable substances are in particular bactericides, deodorants, anti-rust agents, colored indicators, whether to indicate the degree of humidity in the air, or even to visualize the degree of saturation of the absorbent (6). These active substances can moreover be applied to the support by any technique known by a person skilled in the art, in particular

  by spraying, coating, soaking or bonding.

  One or more elements of the pocket can be used

  to support these active substances.

  This is the case of the bag (5) which can serve as a support for these various active substances. In this case, the material of the pocket (5) is capable of allowing the active substances which it supports to diffuse in

the environment to be treated.

  The absorbent (6) can also serve as a support for the active substances mentioned above. Another alternative is to mix the absorbent (6) with a support material for the active substances. Advantageously, the support material for the active substances is an adsorbent which allows the desorption and the diffusion of the active substance in the humid environment. It is also possible to provide a support

  independent of the pocket (5) for these active substances.

  This independent support can be fixed outside o inside the device by any means known to man

  of the trade, in particular by gluing, welding or stapling.

  The device (1) according to the invention can comprise any means known per se by those skilled in the art making it possible to suspend or maintain it in the environment to be treated. Such a means makes it easier to set up the device (1) in the environment to be treated. Advantageously the packaging box in which is

  sold the device according to the invention allows to suspend.

  As mentioned above, in a particular embodiment of the device (1) according to the invention, the first region (2) defines a first chamber (2c) is in communication with the second region (3) which defines a second chamber (3c), said second chamber (3c) being intended to recover the liquid (7) from

  absorption by the absorbent of humidity (6).

  In this embodiment, the first chamber (2c) is assembled in a sealed manner and is in communication with the second chamber (3c) of the device. In other words the two chambers (2c) and (3c) communicate between

  they and define a volume impermeable to liquids.

  In practice, the two chambers are in communication so that the liquid absorbed in the first chamber (2c) can be recovered and stored in the

second bedroom (3c) for.

  When this particular embodiment of the device (1) according to the invention is put into operation, the water vapor (H) contained in the humid air is absorbed by the absorbent (6) through the pocket (5) and the material of the first chamber (2c), both permeable to moisture. Once absorbed, the water vapor present in the humid air is condensed and forms a solution with the absorbent (6). This liquid is then recovered in the

second bedroom (3c).

  Due to the tightness of the device, the absorbed liquid (7), which forms a solution with the absorbent (6), cannot contaminate the external environment. By environment is meant, in the present application, the humid external environment to be treated which is located

proximity to the absorbent device.

  According to an advantageous embodiment of the device (1) absorbing moisture according to the invention: - the first region (2) is produced from material of the TYVEK brand; - The second region (3) is made from polyethylene; - the pocket (5) is made from micro-perforated polyethylene; - the moisture absorbent (6) is magnesium chloride;

  - the peelable film (8) is made of polyethylene.

  These elements are preferably assembled by thermal welding, so that the moisture-absorbing device (1) is completely liquid-tight vis-à-vis

from the outside environment.

  The device according to the invention provides numerous

consumer benefits.

  First of all, it should be emphasized that the device (1) according to the invention is single-use. It is therefore discarded once the absorbent (6) is used up, that is to say when it is saturated and it no longer fulfills its moisture absorption function. The user therefore does not need

  open the device to recharge it by absorbing (6).

  This has the advantage of avoiding the risk of spilling the absorbent (6) or the liquid resulting from absorption in the environment to be protected. The device (1) according to the invention therefore remains completely sealed vis-à-vis the environment to be treated and this, throughout its

lifetime.

  Furthermore, the device (1) according to the invention has the advantage of being simpler to manufacture and more solid than the devices of the prior art. The present invention therefore makes available to the consumer a more affordable, simpler device.

of use and more solid.

  The invention will be described in more detail using the figures which follow, without however limiting

  the invention only in the embodiments shown.

  Figure 1 is a front view of a mode of

  realization of the device according to the invention (1).

  Figure 2 is an exploded view of the same mode of

  realization of the device according to the invention (1).

  Figure 3 is a three-quarter view and partially broken away of this embodiment of the

  device according to the invention (1) in operation.

  Figure 4 is an exploded view of another mode of

  realization of the device according to the invention.

  In Figure 1, the moisture absorbing device (6) (1) comprises a first region (2) defining a first chamber (2c) and a second region (3) defining a second region (3c). In the embodiment shown, the first and second chambers (2c) and (3c) are rectangular envelopes having one side open in sealed communication with one another. The first chamber (2c) is made from a material (4) impermeable to liquids but permeable to moisture and is protected from the air by a protective film (8). This protective film (8) is removed to put the device (1) into service. Indeed, once the film (8) removed, the chamber (2c) is in contact with the humid air. The water vapor contained in this humid air will be absorbed

  by the absorbent (6) (not shown in Figure 1).

  The second chamber (3c) is welded to the first chamber (2c) along the weld lines (9) and in area so that the first and second chambers

(2c), (3c) communicate.

  Figure 2 shows an exploded view of the device according to the invention (1). The first chamber (2c) comprises two sheets of a material impermeable to liquids but permeable to moisture (2A) and (2B), which are covered by two sheets of a protective film (8A) and (8B), impermeable liquids and moisture. The liquid-permeable pocket (5) (7) is shown open in this exploded view. It includes perforations (5P) and contains an absorbent (6). The second chamber (3c) is produced from two sheets impermeable to liquids (3A) and (3B). During assembly, the sheets (2A) and (2B) are respectively welded at their edges to the sheets (3A) and (3B). The sheet constituting the pocket (5) is folded in half lengthwise and placed between the welded parts (2A) - (3A) and (2B) - (3B). The parts (2A) - (3A), (2B) (3B) and the sheet constituting the pocket (5) are then welded to each other on their lateral and lower edges, with the exception of their upper edge, which will fill the pocket (5) with the absorbent (6). Once the pocket (5) is filled, a weld completes the closing of the device (1) on the upper edge. The materials of the device (1) which are in contact with the outside, in this case the materials of the first and second chambers (4) and (3) are impermeable to liquids. The device (1) is therefore completely impermeable to liquids vis-à-vis the outside. In this way, the exterior is preserved from any contamination by the absorbent (6) or by the liquid (7) (not shown in Figure 2) from

absorption.

  Figure 3 shows a sectional view of the device according to the invention (1) during its operation. The film (8) has been removed to allow the absorbent (6) to absorb the moisture-laden air represented by the arrow (H) which passes through the sheet of material impermeable to liquids but permeable to moisture (4 ). The moisture absorbed by the absorbent (6), inside the pocket (5), is condensed and forms a liquid (7) in association with the material (6). This liquid (7) passes through the pocket (5) which is permeable to liquids, but cannot pass through the sheet (4) of the first chamber (2c) since this is made from a material impermeable to liquids. The liquid (7), subjected to gravity, is recovered in the second chamber (3c) which is also made of material impermeable to liquids. The absorbed moisture and then the recovered liquid (7) are therefore held captive inside the device (1). This is particularly important, especially when using concentrated magnesium chloride as an absorbent (6). Indeed, the liquid (7) recovered is a brine which can be aggressive vis-à-vis the environment. The ring

  (10) allows the device to be suspended from a hook.

  Figure 4 shows an exploded view of another embodiment of the device according to the invention (1). The first region (2) comprises a single sheet of liquid impermeable but moisture permeable material which is covered by a sheet of film

  protector (8), impermeable to liquids and humidity.

  The liquid-permeable pocket (5) (7) is shown open in this exploded view. It includes perforations (5P) and contains an absorbent (6). The second region (3) which defines a chamber (3c) is produced from two sheets impermeable to liquids (3A) and (3B). During assembly, the sheet (2) is welded on its edges to the sheet (3A). The sheet constituting the pocket (5) is folded in half lengthwise and placed between the welded parts (2) - (3A) and (3B). The pieces (2) - (3A), (3B) and the sheet constituting the pocket (5) are then welded to each other on their lateral and lower edges, with the exception of their upper edge, which will allow filling the bag (5) with the absorbent (6). Once the pocket (5) is filled, a weld completes the closure of the device (1)

on the upper border.

  The following examples are intended to illustrate particular embodiments of the device according to the invention without limiting the invention to these

only embodiments.

  EXAMPLE 1 OF A DEVICE ACCORDING TO THE INVENTION

  A moisture absorbing device (1) of rectangular shape is produced, in accordance with the invention, and of total dimension 57 x 24 cm with the following materials: - a sheet of TYVEK 1073B of dimension 19.5 x 24 cm for the first region (2), - two sheets of polyethylene, one of dimension 38.5 x 24 cm and the other of dimension 57 x 24 cm

for the second region (3).

  - a sheet of micro-perforated polyethylene (6 perforations of approximately 0.25 mm per cm2) of

  size 32 x 24 cm for the pocket (5).

  The sheets are welded together to obtain the device according to the invention illustrated in FIG. 4, the pocket (5) being filled with 1 kg of 96% magnesium chloride.

  EXAMPLE 2 OF A DEVICE ACCORDING TO THE INVENTION

  A moisture absorbing device (1) of rectangular shape is produced, in accordance with the invention, and of total dimension 57 x 24 cm with the following materials: - two identical sheets of TYVEKE 1073B of dimension 19.5 x 24 cm for the first chamber (2), - two identical sheets of polyethylene 38.5 x 24 cm in size for the second chamber (3). - a sheet of micro-perforated polyethylene (6 perforations of approximately 0.25 mm per cm2) of

  size 32 x 24 cm for the pocket (5).

  The sheets are welded together to obtain the device according to the invention illustrated in FIG. 2, the pocket (5) being filled with 1 kg of magnesium chloride

96%.

Claims (12)

  1. Device (1) for absorbing moisture comprising a moisture absorbent (6), a wall comprising a first region (2) and a second region (3), said device being characterized in that: the first region (2) of the wall is impermeable to liquids but permeable to moisture; - The second region (3) of the wall is impermeable to liquids; said wall defining a volume impermeable to   liquids and containing the absorbent of humidity (6).   2. Device (1) according to claim 1, in which the first region (2) defines a first chamber (2c) and is in communication with the second region (3) which defines a second chamber (3c), said second chamber ( 3c) being intended to recover the liquid (7)   resulting from absorption by the moisture absorbent (6).   3. Device (1) according to claim 1 or 2, wherein the first region (2) of the wall is made at least in part from a non-woven and / or tear-resistant material (4), preferably to base of high density polyethylene filaments and more preferably at TYVEK brand material base.   4. Device (1) according to any one of   claims 1 to 3, wherein the second region (3)   of the wall is made from a film of laminated, extruded or coextruded material, preferably from a polyethylene film.   5. Device according to any one of   claims 1 to 4 further comprising a pocket (5)   placed inside the volume defined by the wall, said pocket (5) being permeable to liquids and moisture and containing the moisture absorbent (6). 6. Device according to claim 5 wherein the pocket (5) is made of non-woven material, or is made from a film of laminated material, extruded or coextruded and micro-perforated, preferably from a film of micro-perforated polyethylene.   7. Device according to any one of   claims 1 to 6, wherein the moisture absorbent   (6) is chosen from the group consisting of chloride-based absorbents, in particular magnesium chloride, sodium chloride, calcium chloride and their   mixtures, preferably magnesium chloride.   8. Device (1) according to any one of   claims 1 to 7, wherein the first region (2)   of the wall is protected from humid air by a film peelable (8).   9. Device (1) according to any one of   claims 1 to 8, further comprising a support for active substance.   10. Device (1) according to claim 9, in   which the active substance support is an adsorbent.   11. Device (1) according to one or other of the   claims 9 and 10, wherein the active substance   is chosen from the group consisting of bactericides, deodorants, anti-rust agents, colored indicators, whether to indicate the degree of humidity in the air, or to visualize the degree of saturation of the absorbent (6).   12. Device (1) according to any one of   claims 2 to 11, in which:   - The first region (2) of the wall is made from TYVEK brand material; - The second region (3) of the wall is made from polyethylene; - the pocket (5) is made from micro-perforated polyethylene; - the moisture absorbent (6) is magnesium chloride;   - the peelable film (8) is made of polyethylene.