MXPA98000195A - Best ventilation methods - Google Patents

Abstract

The present invention relates to a container, or a lid for a container, to contain viscous liquid products, the container or cover comprises ventilation means, said ventilation means allow the passage of gases between the inside and outside of the container when the pressure inside said container differs from the external environmental pressure, said container or lid further comprises control means controlling the phase separation of said product sprinkled on the membrane

Description

IMPROVED PE VENTILATION METHODS FIELD OF THE INVENTION The present invention relates to a container, or a cover for a container, comprising ventilation means. This container or lid further comprises means that prevent a substantial decrease in the ventilation capacity of said ventilation means.

BACKGROUND OF THE INVENTION The problem of deformation of the container in response to the pressure differences that exist between the interior of a closed container and the ambient pressure is well known in the packaging industry. Such deformation of the container may be non-recoverable for certain container materials, such as some plastics or metals. The partially flexible thin walled containers are particularly sensitive to the problem. There are a number of possible factors that can lead to the existence of pressure differences between the inside and the outside of the aforementioned container. The contents of the container, for example, may be chemically unstable or may be reacted with gases that may exist in the upper space of the container, or alternatively, in certain specific circumstances, may react with the container material itself. Any chemical reactions that involve the liquid content can lead to the production of gases and therefore to the overpressure in the container, or to the absorption of any gases in the upper space thus causing a low pressure in the container. The pressure differences between the pressure inside the container and the ambient atmospheric pressure can also occur when the temperature between the filling and sealing of the container is significantly different from the external temperature during shipping, transport and storage. Another possibility of a pressure difference can be caused by a different environmental pressure in filling the container with another environmental pressure at a different geographical location. The prior art has proposed several solutions that use valve systems that avoid pressure differences between the interior and exterior of the container. The proposed solutions also relate to several vent covers that allow the pressure generated inside the container to be released by the gas leak. For example, FR-A-2 259 026, US-4 136 796 and DE-A-2 509 258 disclose self-venting closures comprising a gas permeable membrane that covers an orifice outwardly. Said membranes are made of a material that is impermeable to liquids, but permeable to gases. Therefore, the containers may comprise openings to release gas to the exterior without losing its leak tightness. Another example is EP-A-593 840 which describes containers for containing pressurizing liquids, said container being made of a thermoplastic material comprising a network of microchannels. This network of microchannels is permeable to gases, but not to liquids. It has been found that if the liquid product makes contact with these membranes, with end of the microchannels, said membranes may lose at least part of their gas permeability. In fact, liquid products that are viscous or have a certain affinity for these membranes may not drain from the membrane into the container. In this way, it can happen that the container loses ventilation capacity. This loss of ventilation capacity results in a pressure difference between the exterior and the interior of the container that can deform it. The contact between said product and the membrane can be used by spraying the product on the membrane as the full container is agitated during shipment and transport of the container. It has been found that the amount of splashing that normally occurs during shipping and transport is sufficient to completely disrupt the ventilation capacity of the container. Other means by which the product can make contact with the membrane is during downward storage of the container. It has been found that the other ventilation systems, as valves, for example, may also suffer from a similar disadvantage. It has also been found that an important parameter that influences the drainage of the product from the membrane is that the product that has come into contact with the membrane can undergo phase separation. Specifically, it has been found that for certain types of products the drainage can be improved when the phase separation is increased. On the contrary, it has also been found that phase separation induced on other different products substantially reduces drainage from the ventilation means, and consequently, reduces the ventilation capacity of the ventilation means. Therefore, the phase separation of the product splashed through the membrane is an important parameter that determines the ventilation capacity of said ventilation means. Therefore, an object of the present invention is to provide a container (10) for a liquid product, or a lid (10) for said container that allows the ventilation of said product by means of ventilation (29) and that allows the control of the separation of phases of said product that is in contact with the ventilation means.

BRIEF DESCRIPTION OF THE INVENTION The present invention provides a container (10) for a liquid product, or lid (10) for said container, the container or lid allowing ventilation of the product by means of ventilation (20). Said ventilation means allow the passage of gases between the inside and outside of the container when the pressure inside the container differs from the ambient pressure. Said ventilation means are permeable to gases, but impervious to the product. The container or lid contains a liquid product of the first group of liquid products, and the container or lid comprises control means (30) that limit the phase separation of the product contained in said membrane. The present invention also provides another embodiment of a container (10) for a liquid product, or a lid (10) for said container, the container or cover allowing ventilation of the product by means of ventilation (20), which on the contrary contain a liquid product of the second group of liquid products, and said container or cover comprises control means (30) that increase the phase separation of the product that makes contact with the ventilation means.

BRIEF DESCRIPTION OF THE FIGURES Figures la, Ib and illustrate cross-sectional side views of a container (partially shown), or of a lid containing means of ventilation. Figures 2a to 2c show the sequence of a test made to confirm the findings of the present invention. Figures 2d and 2f are diagrams showing the result of the test with different levels of phase separation. Figure 3 is a diagram illustrating the viscosity as a function of the shear rate of a typical composition having a non-Newtonian flow behavior of low shear as compared to the viscosity of the separate portions in its shear phases. composition.

DETAILED DESCRIPTION OF THE INVENTION Next, the drawings may refer to a portion of a container as well as a lid or as well as any structure, such as a lid, attached to the container. In fact, the present invention can be part of a lid only, whereby said lid can be hooked to any container filled with gasable liquid products. A lid of the type of screwing / unscrewing or closed by pressure / open by pressure, or a top cover, push-pull or turret closures can be coupling means between the lid and the container. Next, Figure A will be described first as a container, then as a lid. In the first case, the Figure shows a side view in cross section of a container, said container (10) (only partially shown) comprises a hollow body (11). Said hollow body may comprise an upper wall (17), a side wall (18) and a lower wall (not shown in Figure la). Said hollow body may contain any liquid products. Preferably, said hollow body is flexible to the extent that it can deform in response to pressure differences arising between the interior of the container and the ambient pressure. Bags made of thin plastic material, for example, can also be included by the present invention. Otherwise, suitable forms of said container may include essentially cylindrical, cylindrical, tapered, oval, square, rectangular or oval-flat. In the event that the Figure represents a cross-sectional side view of a lid, the lid (10) comprises an upper wall (17) and a side wall (18). The lid can be coupled in a leak-tight manner to the container described above. In another preferred embodiment of the present invention, said container or lid (10) may comprise a nozzle. Preferably, said container or lid is made of plastic, metal, paper or combinations of these materials as layers, laminated materials or co-extruded products. The materials can also be recirculated. Preferred materials for said hollow body include plastics such as polyethylene (high or low density), polyvinyl chloride, polyester, polyethylene terephthalate (= PET) extrudable PET, polypropylene, polycarbonate and nylon. These plastics can be used individually or can be combined as co-products, laminates, laminates or laminated materials. As another essential feature, said container or lid (10) comprises ventilation means (20). Said means of ventilation can equalize the pressure inside the container with the external atmospheric pressure. As a consequence, said ventilation means can avoid excess pressure as well as lack of pressure inside the container. In fact, said ventilation means allow the escape of gases released from the product contained from the interior to the exterior of the container, or vice versa. Said ventilation means are located in the upper portion of the container above the level of said contained product, when the container is in its upright position. In fact, the gases cause excess pressure or lack of pressure to accumulate in the upper region of the container. Therefore, the passage of gases to the outside or inside is facilitated. Preferably, said ventilation means comprise at least one hole (21) and one membrane (22). Said hole connects the inside of the container with the outside. Specifically, the orifice (21) allows the passage of gases from the interior to the exterior of the container, or vice versa, in such a way that the pressure inside the containers maintained identical to the external atmospheric pressure or to a pressure at least below the pressure at which occurs the important deformation of the bottle. Said hole may be located on the upper wall or on the side wall. As another preferred option, said hole is part of a separate part of the hollow body (11) of the container, whereby said part can be fixed on the hollow body. The size of this hole must be adequate for the passage of gases. The membrane (22) covers the hole and is located between the contents of the hollow body (11) and the hole (21) inside or outside of said hollow body (11). Said membrane is impermeable to liquid, but permeable to gases. Therefore, the membrane can provide a liquid impervious barrier, while allowing gas ventilation. Preferably, said membrane can be impermeable to liquids up to pressure differences of 1 bar between the inside and outside of the hollow body, preferably up to pressure differences of 500 mbar. The membrane can be a flat surface, at least when viewed macroscopically. The membrane may also comprise a network of microchannels that is permeable to gases, but not to liquids, as described in EP-A-593 840. Said membrane can be corrugated macroscopically, as a zigzag surface, in which case the membrane is defined by several planes of different inclination with respect to the horizontal direction, connected to each other.

Preferably, said membrane (22) is any material capable of forming within a thin layer that can be used to cover the orifice (21). The membrane must be permeable to the flow of gases, also in response to small pressure differences. Preferably, the membrane should allow the flow of gas with pressure difference as low as 50 mbar, most preferably as low as 5 mbar. The thickness of said membrane is a matter of choice, but preferably it will be in the region of 0.2 mm to 2 mm. The membrane can essentially comprise any material that can be formed into thin layers such as plastics, paper or metal having microporous fibers. Preferred materials for said membrane include microporous plastic films. The size of the microporous membranes of said membrane must be such as to allow the passage of gases at low pressure differences and at the same time to provide a high level of liquid impermeability. Preferably, the iopores will be in the range of 0.1 μ to 5 μ, most preferably between 0.2 μm to 1 μm. Preferably, said membranes have a rounded shape. But other shapes such as rectangular, triangular or other, can also be considered to adapt them in a container or lid and / or improve the aesthetics of the container or lid itself. Preferred microporous plastic films for this application are: non-woven plastic films, especially the non-woven spin-bonded polyethylene film material sold under the trade name TYVEK by the Du Pont Company, of which TYVEK, Style 10, is treated with fluorocarbon to achieve high fluid impermeability; - an acrylic copolymer cast on a non-woven support (nylon or PET) with hydrophobic character after fluoro-monomer treatment, sold under the tradename VERSAPOR, by Gelman Sciences Company, 600, South Wagner Road, Ann Arbor, MI 48106, US. The microporous film material of said membrane (22) can be treated to reduce its surface energy and thereby improve the liquid impermeability of said film material. The reduction of the surface energy of the film material is particularly necessary to improve its impermeability when the container (10) contains products comprising surfactant components. Preferably in this case, the specific surface energy of the film material must be less than that of the surfactant-containing product to achieve a substantially complete impermeability to the content of the product. The fluorocarbon treatment, which involves attaching a fluorocarbon material, to an icoscale, to the surface of the film material is a specific example of a treatment that provides such reduced surface energy. In fact, the fluorination treatment reduces the susceptibility of the microporous film material of the membrane to wetting by the content of liquid products. However, when used to treat microporous film material of said membrane in accordance with the present invention, this fluorocarbon treatment must not compromise the gas permeability of the membrane. For example, a possible fluorocarbon material for use in the fluorocarbon treatment according to the present invention is sold under the trade name SCOTCHBAN by 3M Company. The membrane (22) can be applied and placed inside or outside the hollow body (11) between the contents and the orifice (21) in any manner that maintains its liquid impermeability and gas permeability in accordance with the present invention. The means of application may therefore include the use of adhesives or heat sealing of the membrane over the area around the orifice or mechanical means such as pressing or heat stamping, or insertion of the membrane during the molding of the container. As stated before, the means of application employed should not significantly compromise the ventilation capacity of the membrane. For this reasonIt is preferred that any adhesive used is also permeable to gases, or does not fill the pores of the membrane. As described in co-pending European Application No. 94870161.0, the membrane (22) can also be fitted within a housing. The accommodations whose dimensions are particularly compatible for use in a container or lid in accordance with the present invention are commercially available from GVS, Via Roma 50, 40069, Zola Predosa (BO), Italy. In a highly preferred embodiment, the manufacture of said housing and the adjustment of the membrane (22) in the housing can be achieved by means of an "insert molding operation", wherein: - a membrane sheet is fed into the apparatus , the sheet of the membrane is advantageously fed from a roll of membrane material; - in said apparatus, at least one membrane is cut from the sheet and placed in a mold where the housing will be formed; then, the housing is molded substantially around the membrane in a manner that secures the membrane within said housing. As "substantially around" it is understood that once complete, this step must generate a housing with its adjusted membrane, wherein both surfaces of the membrane are accessible to air, but said membrane is hermetically maintained in the housing. The housings can also be manufactured by heat sealing, ultrasonic sealing or gluing said membrane (22) inside the housing. In addition, the housings can be manufactured by mechanically maintaining the membrane between two separate pieces so that said pieces are held together.

It has been found that the ventilation performance of said ventilation means (20) can be substantially reduced when the contained liquid product makes contact with the membrane (22). As explained above, said membrane is the most exposed part of the ventilation means towards the contained product. The contact between the product and the membrane inside a container can occur mainly through splashing during the shipment and the transport with agitation of said container. As used herein, "splashing" means a non-continuous and brief contact of a liquid substance on a surface when said liquid is stirred within the container. The splash of the contained liquid product occurs mainly during the shipment and transport, when the risk of agitation of the container is greater. It was found that these membranes can lose their gas impermeability when the liquid product content makes contact with the membrane (22). In fact, it was found that the liquid product or part of said product may not drain sufficiently from the membrane. In this way, the membrane or part thereof can be covered by the product, that is, the ventilation performance of the membrane is reduced for any part of the membrane covered by the product that has not been drained. Consequently, the ventilation capacity of the container is effectively reduced or lost. This is particularly the case for liquid products that are viscous or have a certain affinity for the membrane. It was found that products having viscosities of at least 5 cps when measured using a Brookfield viscosity meter at 60 rpm, spindle 3 and at 20 ° C demonstrate poor drainage from the membrane. Other examples are liquids that exhibit non-Newtonian flow behavior, shear thinning, or liquids that have a low surface energy (<30 dynes / cm2). For example, liquids comprising surfactants typically exhibit a shear thinning flow behavior. As used herein, a product with "shear thinning" is a product having a high viscosity when the shear rate is low, and conversely, its viscosity is low when the shear rate is high. A product of thinning by shear stress presents a poor drainage from said membrane. It is believed that, due to the product flow characteristics observed during drainage, the shear rate of the product directly adjacent to the membrane is low. Consequently, the final layer of product adjacent to the membrane has an intrinsically high viscosity. Therefore, drainage of the dinal layer of the product from the membrane is avoided. The contact between the contained liquid product and the membrane (22) occurs mainly during the shipment and transport of the container. In fact, the liquid product splashes on the membrane inside the container when the container is stirred. It was found that the amount of splashing that normally occurs during shipping and transport is sufficient to completely disrupt the container's ventilation capacity. Other means by which the product can make contact with the membrane is during downward storage of the container. It was found that other ventilation systems, such as valves for example, may also suffer from a similar disadvantage. Accordingly, the present invention provides a container for a liquid product, or a lid for said container that improves the drainage of said liquid product away from the membrane. One possible way to remove the splashed product from the membrane is to scrape the surface of the membrane splashed by the product. It was found that the ventilation capacity of said membrane was sufficiently recovered to avoid significant deformation of the bottle once the splashed product was scraped off the surface of the membrane. Scraping the surface can be achieved with a device that has, for example, the shape of a shovel. Although this solution solves the problem of the present invention, it has two important disadvantages. First, the scraping action must be carried out either manually by the user, which is inappropriate, or by a mechanical movement device within the container, which can be complex and expensive. Second, the scraping action of said product sprinkled from the membrane can damage the membrane. In fact, especially the impermeability of said membrane to liquids can easily be lost through scraping. The Copending European Patent Application No. 95104281. 1 provides a container or lid in which the splashed product is capable or prevented from draining from the membrane automatically without any scraping of the membrane. These means may comprise the placement of the ventilation means in an inclined or vertical plane with respect to the support plane on which the container rests in its upright position. This is shown, for example, in Figure Ib, whereby the membrane (22) is vertical. Alternatively or in combination, said means comprise drainage means (23) extending from and in connection with the ventilation means, as illustrated in Figure le. Said drainage means are preferably inclined or vertical with respect to the support plane on which the container rests in its upright position. The aforementioned Copending European Patent Application describes that these means that improve the drainage of the splashed product onto the membrane ensure effective ventilation of said ventilation means. It has now been found that the drainage of the product splattered from the membrane is influenced by the phase separation of the liquid product on the membrane (22). In fact, it was found that the separation of phases of said product on the membrane can limit or increase the drainage of the product away from the membrane, depending on the type of the liquid product. In fact, two different groups of liquid products were distinguished. The distinguishing characteristic between these two groups is the change in viscosity after the phase separation of the liquid product on the membrane. In the following, "liquid product" is a composition comprising at least one liquid phase having a viscosity of at least 5 cps using a Brookfield viscosity meter at 60 fm, screw 3 and at 20 ° C. "Phase separation" means that the liquid product is separated into at least two distinct portions of matter, whereby said materials may be in the liquid state, gaseous state, dry solid state or mixtures thereof. The first group comprises liquid products having at least a separate portion of the material phase having an increased viscosity with respect to the viscosity of the liquid product before its phase separation. On the contrary, the second group comprises liquid products having all the portions of matter separated in phases of reduced viscosity with respect to the viscosity of the liquid product before their phase separation. It was observed that the first group comprises liquid products having a substantially Newtonian flow behavior, as compared to the second group containing liquid products having a non-Newtonian flow behavior, substantially shearing thinning. As used herein, a product having a "Newtonian flow behavior" is a product of substantially constant viscosity over a wide range of shear rate, whereas a product having non-Newtonian shear thinning behavior is shows, for example, in Figure 3, so the curve connecting the filled squares is before phase separation, and the line connecting the empty squares is after phase separation. phases of a liquid product of the first group (hereinafter called "first liquid product") on the membrane (22) must be at least limited or completely avoided, in fact, the portion that is separated into phases of the first liquid product , has an increased viscosity with respect to said first liquid product.This means that this portion has an even lower tendency to drain away from the liquid. In this way, this portion partially covers or covers said membrane reducing the ventilation capacity of the membrane. Conversely, a phase separation of a liquid product of the second group (hereinafter referred to as "second liquid product") on the membrane should be encouraged. In fact, the portions that are separated in phases from the second liquid product have a lower viscosity with respect to the second liquid product. Therefore, these portions of the second liquid product drain more easily away from the membrane, avoiding covering and reducing the ventilation capacity of the membrane. Examples of first liquid products are non-emulsified liquid products, such as the following composition used for laundry treatment by hand and / or in washing machine. In the following, "minor components" are optional ingredients of the compositions or products such as stabilizers, chelating agents, radical scavengers, surfactants, bleach activators, detergency builders, soil suspensions, dye transfer agents, solvents, to rillantadores, perfumes, suppressors of foams and dyes.

EXAMPLE I Incentrators Po weight percent Hydrogen peroxide 14.00 Sodium oxide hydroxide 10.00 1, 2 ppannediol 9.00 C12-C14 ethoxylated alcohol, 7 EO 11.00 Linear alkylbenzene sulfonate 18.75 Fatty acid 7.50 Water + minor components the rest It was found that the portion that is separated in phases from the first liquid product of Example I is gelled on said membrane, permanently covering the membrane if the gel portion is not mechanically removed from the membrane. In the subsequent "gel" refers to strongly viscous solutions. Therefore, said membrane loses at least partially its ventilation capacity. Examples of second liquid products are non-Newtonian emulsions of shear thinning. These emulsions are described, for example, in co-pending European Patent Application No. 92870188.7, in which a hydrophobic liquid ingredient is emulsified in the composition using a mixture of specific nonionic surfactant. Following are other specific examples of second liquid products.

EXAMPLE II Ingredients Percent by weight Hydrogen peroxide 7.5 Acetyl triethyl citrate 7.0 Dobanol 23-3 6.4 Dobanol 45-7 8.6 Sodium alkyl sulfate 2.0 H2SO4 up to pH4 Water + minor components the rest EXAMPLE III Ingredients Percent by weight Hydrogen peroxide 6.0 Acetyl triethyl citrate 3.5 Neodol 45-7 8.1 Lutensol T03 6.9 Sodium alkyl sulfate 2.0 H2S04 up to pH4 Water + minor components the rest In this case, the portions that are separated in phases from a second liquid product are not gel on said membrane. In contrast, the separate portions have individual viscosities that are lower compared to the viscosity of the initial liquid second product. In fact, the viscosity of the second liquid product of Example II is typically between 1200 cps and 1800 cps measured using a Brookfield viscometer at 50 rpm, spindle at 3 to 20 ° C. However, the viscosities of the separate portions in corresponding phases are typically less than 100 cps measured using the same test parameters as before. It is found that said phase separated portions show less non-Newtonian behavior than the initial composition of Example II. Consequently, the separated phases are more capable of draining away from the membrane, thus allowing ventilation through said membrane. The same effect has been observed with the second liquid product of Ejeplo III, whose viscosity before phase separation is typically between 1000 cps and 1400 cps measured using a Brookfield viscosity meter at 50 rpm, spindle 3 at 20 ° C. It was found that phase separation of the first and second liquid products in the membrane can be achieved by two different mechanisms: evaporation and / or hydrophobicity. These two mechanisms can also be combined with one another to achieve an increased effect. If certain components within the liquid product evaporate through the membrane (22) and the orifice (21), the phase of the liquid product is separated. In fact, without being bound by any theory, it is believed that the porous material of said membrane connected to the orifice allows certain components to evaporate through the membrane, thus decomposing the liquid product into physically distinct portions of matter on the membrane. Evaporation is increased by maximizing the open area of said membrane (22). Said open area of the membrane is the amount of area of said membrane exposed to the outside of the container or lid. Thus, the open area may depend on the size and number of holes (21) that contact the membrane outside the container or lid. Therefore, an open area increased to the maximum increases the evaporation of certain components of said liquid product, and consequently increases the phase separation of the liquid product. This is demonstrated by the following test results. As illustrated in Figures 2a to 2c, a membrane of type Versapor * V800R closes an open end of a cylindrical tube (41). In this way, the membrane comprises an internal surface (42) directed towards the interior of the cylindrical tube, while the opposite external surface (43) is completely exposed to the exterior of the cylindrical tube, the open area of the membrane also being. The open area of the outer surface (43) can be reduced by covering the outer surface with a polyethylene film comprising a pin hole. This membrane undergoes repeated splashes (Figure 2a) with a liquid product (44), so that the liquid product remains on the inner membrane for 1 minute. Subsequently, said splashed liquid product is allowed to drain away from the membrane for 24 hours by turning the inner surface downwards. Physically, the ventilation pressure is measured after 24 hours of drainage using a bubble point method. This complete procedure has been repeated three times. The "bubble point method", mentioned above, comprises the following steps: placing a thin layer of water on the outer surface (43) of the membrane closing an open end of the cylindrical tube (41); increase the pressure in said tube at a rate of 100 mbars per minute; - record the pressure at which air bubbles are seen to pass through said membrane. This detected pressure defines the previous ventilation pressure. Figure 2d represents the ventilation pressure after one, two and three splashes after a first liquid product as illustrated in Example I. When the outer surface (43) is not covered by said polyethylene film comprising a hole of pin, the ventilation pressure increases with each splash (empty frames).

This means that the ventilation capacity of the membrane is reduced when the first liquid product makes contact with the membrane. On the other hand, when the outer surface (43) of the membrane is covered by the polyethylene film, a substantial increase in the ventilation pressure can not be observed (full frames). The ventilation capacity of this protected membrane is maintained substantially intact. This means that by limiting the open area of the outer surface (43), the capacity of ventilation through the membrane does not cancel out. Therefore, draining the first liquid product away from the inner surface is stimulated when evaporation through the membrane is limited. It was found that this is true for any liquid product that is within the group of the first liquid products as defined above. Instead, Figure 2e represents the ventilation pressure after one, two and three splashes of a second liquid product as illustrated by the composition of Ejeplo II. When the outer surface (43) is completely exposed to the outside of the tube (41), a substantial increase in the ventilation pressure (empty frames) can not be observed. The ventilation capacity of this protected membrane is maintained substantially intact. On the contrary, when the outer surface (43) of the membrane is covered by said polyethylene film, the ventilation pressure increases with each splash (filled squares). This means that the ventilation capacity of the membrane is reduced when the second liquid product makes contact with the membrane. This means that by limiting the open area of the outer surface (43) the ventilation capacity through the membrane is substantially nullified. Therefore, the drainage of the second liquid product away from the inner surface of the membrane is stimulated when the evaporation through the membrane is maximized. This is also shown in Figure 2f. The first two splashes are made when the membrane is covered by polyethylene film with a hole. As before, the ventilation pressure increased. But before the last splash, the polyethylene film is removed, and an immediate drop in ventilation pressure is achieved after another splash. The same result has been observed with the composition of Example III and this is true for any liquid product that is within the group of the second liquid products as defined above.

In this way, an essential feature of the present invention are control means (30) that control the phase separation of the product on the membrane (22). These control means can increase or reduce the phase separation on the membrane. As described above, when said container contains a first liquid product the control means must limit or prevent the phase separation of the first liquid product on the membrane by reducing the open area of the membrane. As a preferred option, the control means are provided by limiting the total size of the hole (21). In fact, the side of the hole itself determines the open area. As an alternative, the size of said hole, and therefore of said open area, can be reduced by fixing a cover on said hole. In fact, the lid, which at least partially covers the hole, is capable of reducing the open area of the membrane. The lid can be a separate or integral part of the container or lid (10). As another preferred option for the first liquid product, the control means (30) is covering the membrane with a polyethylene film comprising a pinhole at least on the surface of the membrane closest to the hole. The size of the pin hole must be such that the phase separation of the first product on the membrane is limited or avoided. Preferably, the size of the open area of said membrane when the container contains liquid product of the first group is limited as a maximum to about 30% of the surface of the membrane closest to the orifice, most preferably the open area is less than 20% of the surface of the membrane closest to the hole. It has been found that other control means are the distance between the membrane and the orifice. In fact, a greater distance between the membrane and the hole reduces the phase separation of the first product on the membrane with respect to a membrane having a smaller distance from said hole. As additional control means, it has been found that a membrane that is not directly exposed to said orifice also has a reduced phase separation of the first liquid product. For example, the overlapping walls (31, 31 ') on the membrane with a free rail (32) can be a way to reduce the exposure of the membrane to the hole. On the contrary, when the container contains a second liquid product, the control means (30) must increase the phase separation of the splashed product on the membrane. Therefore, control means are completely exposing a surface of the membrane to the outside of the container. Preferably, the size of the orifice is maximized for the second liquid product to enlarge the open area. Therefore, at least a partial evaporation and consequently a phase separation of the splashed product is increased on the membrane. As mentioned before, this increases drainage away from the product splashed on the membrane. The maximum size of said orifice is limited by the size of the container or lid. Preferably, the size of the open area when the container contains liquid products of the second group is at least 30% of the surface of the membrane closest to the orifice, most preferably at least 50% of the surface of the membrane closest to the orifice . As another option for the second liquid product, there are control means (30) that expose the membrane (22) to the air flow out of the container or cover. This can be achieved, for example, by making the membrane located above the top wall (17) of the container or lid. In this case, at least part of said membrane extends above the upper wall through the hole (21). To protect the membrane against damage during storage, transport and handling of the membrane, it can be covered by a wrap. Said casing may then comprise at least one orifice for the flow of air through the interior of the cover to pass to the membrane. It was found that this air flow further increases the phase separation of the second liquid product on the membrane. Alternative control means (30) for said second liquid groups to control the phase separation on the membrane is a hydrophobic membrane. Next, "hydrophobic membrane" is a membrane (22) as described above having at least one surface directed towards the interior of the liquid product of the container that is more hydrophobic than the liquid product. Said hydrophobic membrane can have all the hydrophobic outer surfaces. In fact, it was found that the hydrophobic membrane can stimulate the phase separation of the liquid product splashed on the hydrophobic membrane. Without being bound by any theory, it is believed that the different components that make up the product may have different surface tensions. Therefore, the internal surface (42) repels these different components differently, thereby stimulating phase separation. This is especially true for the thin layer of liquid product that remains on the inner membrane surface after the drainage of the liquid product has occurred. It was found that phase separation with a hydrophobic membrane has a significant effect on the second group of liquid product comprising oily emulsions. In the meantime, the hydrophobic character has substantially no effects on the first liquid products. Therefore, said hydrophobic membrane can be used in combination with evaporation to increase the drainage of the splashed product away from the membrane.

Claims (14)

NOVELTY OF THE INVENTION CLAIMS

1. A container (10) for a liquid product or a lid (10) for said container, container or lid allowing ventilation of the product by means of ventilation (20), said ventilation means allowing the passage of gases between the interior and the outside of the container when the pressure inside the container differs from the environmental pressure, said ventilation means being permeable to gases, but impervious to the product, characterized in that said container contains a liquid product of the first group of liquid products, said container or lid comprises means of control (30) that limit the phase separation of the product contained in the ventilation means.

A container or lid according to claim 1, further characterized in that the ventilation means (20) comprise a hole (21) connecting the interior to the exterior of the container, and a membrane (23) covering the orifice that it allows the passage of gases, but prevents the passage of liquid products, and said control means (30) control the size of the open area of the membrane (22).

3. A container or lid according to claim 2, further characterized in that the open area is limited by a lid fixed on the hole.

4. A container or lid according to any of claims 2 and 3, further characterized in that at least the surface of the membrane exposed to the hole is covered by a film made of polyethylene, said polyethylene film comprising a pin hole.

A container or lid according to any of claims 2 to 4, further characterized in that the open area of the membrane is from about 0% to about 30% of the surface of the membrane that is exposed to said orifice.

6. A container or lid according to claim 1, further characterized in that said ventilation means (20) and / or membrane (22) of the ventilation means are placed in a plane inclined with respect to the support plane on which said container rests in its upright position.

A container or cover (10) according to claim 1, further characterized in that the ventilation means further comprise drainage means (23) extending from and connecting to the ventilation means and / or membrane, and said drainage means extend in an inclined or vertical direction with respect to the support plane on which the container rests in its upright position.

8. A container (10) for a liquid product or a lid (10) for said container, the container or cover allowing ventilation of the product by means of ventilation (20), said ventilation means allowing the passage of gases between the interior and the exterior of the container when the pressure inside the container differs from the ambient pressure, said ventilation means being permeable to gases, but impermeable to the product, characterized in that said container contains a liquid product of the second group of liquid products, said container or lid comprises control means (30) that limit the phase separation of the product contained in the ventilation means.

A container or lid according to claim 8, further characterized in that the ventilation means (20) comprise a hole (21) connecting the interior to the exterior of the container, and a membrane (23) covering the orifice that it allows the passage of gases, but which prevents the passage of liquid products, and said control means enlarge the opening area of the membrane, preferably enlarging the size of the hole 21.

10. A container or cover according to claim 9, further characterized in that the size of said hole (21) is enlarged.

A container or lid according to claim 8, further characterized in that the size of the open area is at least 30% of the surface of the membrane that is exposed to said orifice.

12. A container or lid according to claim 8, further characterized in that said membrane (22) has at least one surface directed toward the liquid product within the container that is more hydrophobic than the liquid product. A container or lid according to claim 8, further characterized in that said ventilation means (20) and / or membrane (22) of the ventilation means are placed in a plane inclined with respect to the support plane on which said container rests in its upright position. A container or cover (10) according to claim 1, further characterized in that the ventilation means further comprise drainage means (23) extending from and connecting to the ventilation means and / or membrane, and said drainage means extend in an inclined or vertical direction with respect to the support plane on which the container rests in its upright position.