MX2008008958A - Flexible receptacle for liquids and method of manufacturing thereof - Google Patents

Abstract

A flexible receptacle for liquid, comprising two walls (15,16) of a flexible material, the superimposed free borders of the said walls being joined by a peripheral weld seam (2) in order to define a sealed internal volume of the said receptacle, a self -sealing pouring nozzle (3) in a corner of said receptacle comprising a spout (4) located towards the outside of the said receptacle, an outlet channel (5) connecting the spout to the internal volume of the said receptacle, a self-closing valve comprising one or more obstacles (6) formed by welding of the two walls and arranged in the said internal volume essentially opposite and close to the channel leading to the spout so as to limit the cross -section of the flow-passage of the liquid between the internal volume and the outlet channel, leaving free at least one narrow channel, wherein the outlet channel is formed by a weld either side of the channel within the volume defined by the peripheral seam, said peripheral seam has a parallelogram shape having an acute angle of less than 80°, and the pouring nozzle is positioned in a corner of the said receptacle with an acute angle.

Description

FLEXIBLE RECEPTACLE FOR LIQUIDS AND M ISMO MANUFACTURING METHOD The present invention relates to a flexible receptacle for liquids, equipped with a self-closing spout, and a process for the manufacture thereof. Flexible receptacles for containing a beverage or other liquid have several advantages in relation to rigid receptacles, and in particular a lower production cost, minimal use of materials, and a smaller volume after use. However, once opened, and in the absence of a separate rigid mold spout, welded or glued to the flexible leaves of the receptacle, these receptacles can not be easily re-closed, and tend to allow the liquid to escape. Accordingly, the user is obligated to hold the receptacle once it has been opened, since it can not be placed on a table or other surface before it has been completely emptied, to avoid accidental spills.

Several flexible receptacles with self-closing spout have been proposed in order to remedy this problem. For example, patents GB 769810 and US 4,988,016 propose a self-closing output spout in which a resistance to the passage of the liquid is created by equipping the receptacles with long and thin channels communicating with the spout, thus developing a high resistance to flow. In these systems, the self-closing action depends essentially on the characteristics of elasticity of the material that constitutes the receptacle, in the dimension of the exit peak, and in the characteristics of the liquid. As another example, US Pat. No. 5,441,1178 proposes a receptacle in which a self-closing effect is created by narrowing or placing another obstacle near the outlet spout, thereby developing a high resistance to passage of the liquid. Furthermore, patent GB 867329 discloses receptacles having self-closing outlet peaks in which a resistance to the passage of the liquid is provided by narrowing or placing an obstacle near the outlet spout such that a high resistance to peel develops. flow of the liquid depending on the viscosity and surface tension of the filling liquid, in conjunction with the size of the passage. In systems that rely on high local strength, such as those described in US Patents 5,441,178 and GB 867329, the self-closing action depends to a large extent on the dimensions of the passage as well as on the characteristics of the liquid, and in particular on its tension surfaces. In all these previous solutions, to achieve a reliable self-closing effect, it is necessary to have a great resistance in the exit channel that strongly limits the speed of the flow, and requires the user to apply a strong compression pressure in order to empty the receptacle In addition, after a first use of the receptacle, the self-closing action tends to decrease, leading to an unwanted spill. Another disadvantage is that in those systems, a certain geometry of the output peak is often usable only for a specific liquid, since the self-closing effect is sensitive to variations in channel dimensions or narrowing. Another limitation of the known solutions is based on the creation of bends after using the receptacle, as described in the US patents US 3,278,085, US 5,228, 782 and US 6,244,468, and GB 1296216. These solutions have the disadvantage of not being self-closing, and require certain operations by the user. In patent WO 2004/087526 a self-closing solution is proposed. This patent describes a flexible receptacle that includes two sheets of a flexible material, which are superposed and assembled by means of a welding seam or by means of glue, to form a sealed internal volume. The outlet tip of the receptacle projects outward into a portion of the receptacle edge, and is connected to the internal volume of the receptacle by means of an output channel. The receptacle contains one or more obstacles, formed by the welding or gluing of two walls, formed in the internal volume near the channel leading to the outlet peak, in order to limit the cross section of the flow passage of the liquid between the volume internal and the output channel. When the receptacle is filled with liquid, a portion of the surface that includes the spout, and limited by the obstacle and by the folds oriented essentially transverse to the obstacles, it arches and creates a valve that blocks the flow of the liquid through the outlet spout. In order to allow the liquid to flow, the user applies a pressure to the receptacle in a direction essentially perpendicular to the plane of the obstacle weld, which has the effect of reducing the arc and bends, and of increasing the pressure on the liquid in the receptacle, allowing the liquid to flow. WO 2004/087526 is included herein by reference. To meet the needs of the emerging market, there is a demand for practical and inexpensive self-closing flexible receptacles made from inexpensive and widely available material. Therefore, an object of the invention is to provide a flexible receptacle for liquids, which is self-closing, economical, and simple in its manufacture. It is advantageous to provide a self-closing receptacle which can be made of very flexible and inexpensive material. It is also advantageous to provide a self-closing receptacle using a process that is respectful of the environment. The objects of the invention are achieved by means of a flexible receptacle as described in claim 1. In the present invention, a flexible receptacle for liquids includes two walls of flexible material, joined by means of a peripheral weld seam or by means of glue, to form an internal sealed volume of said receptacle, a nozzle self-sealing weir in a corner of said receptacle comprising an outlet spout located towards the outlet of said receptacle, and an outlet channel connecting the outlet spout to the internal volume of said receptacle formed by a weld seam in each case. side of the flow-passage channel, within the volume defined by the peripheral seam. The peripheral seam of the receptacle of the present invention is in the general form of a parallelogram having an acute angle of less than 80 °, and the mold spout is formed by welding or gluing in a corner of the receptacle at an acute angle. Advantageously, the receptacle includes one or more obstacles formed by the welding or bonding of the two walls and placed in said internal volume essentially opposite and close to the channel leading to the outlet spout, in order to limit the cross section of the container. passage of liquid flow between the internal volume and the outlet channel, leaving at least one narrow channel free. The internal angle of the corner with the acute angle can be between 50 ° and 80 °, and preferably between 60 ° and 75 °. Advantageously, the general parallelogram shape of the receptacle according to the invention allows a corner of said receptacle to act as a pouring nozzle, while also executing the self-closing function in an efficient and reliable manner, without requiring any cutting. of the walls for the formation of the pouring nozzle. The receptacle according to the invention it can thus be manufactured from very flexible polymer sheets, used in a conventional manner for the manufacture of flexible, rectangular shaped, and economical receptacles, without waste of materials, using known processes for soldering and separation of receptacles successive, from continuous sheets of flexible material in the production line. In particular, the problems associated with the cutting of very flexible materials are avoided which, due to their very high plastic deformation, require very precise mechanical tools or other cutting methods incorporated in a non-standard production line, increasing thus the cost of production. The receptacle according to the invention can therefore be manufactured from extruded polymer, used conventionally, inter alia, in the food industry to contain liquid foods, for example polyethylene or polyvinyl chloride. The objects of the invention are also achieved through a process for the manufacture of flexible self-closing receptacles according to claim 8. In the present invention, a process for manufacturing a flexible self-closing receptacle for liquids comprises the following characteristics: overlaying two sheets of flexible material or folding over a sheet of flexible material to form two walls of said receptacle , welding the two walls to form a weld seam defining a peripheral edge of the receptacle having a parallelogram shape with an acute angle of less than 80 °, welding a pouring nozzle located in a corner of the receptacle at an acute angle, having an output peak located outwardly of said receptacle, and an output channel connecting the output peak to the internal volume of said receptacle wherein the output channel is formed by welding a seam on each side of the channel within the volume defined by the peripheral seam, and welding of one or more obstacles positioned in said internal volume essentially opposite and close to the channel leading to the outlet peak, to limit the cross section of the liquid flow passage between the internal volume and the channel of exit, leaving at least one narrow channel. Advantageously, the described process allows the simultaneous or continuous manufacture of several flexible receptacles for liquids. These flexible receptacles can be produced from a large sheet of flexible material. The receptacle according to the present invention is of very simple construction and manufacture, without requiring any cutting of flexible walls around the pouring nozzle to form the latter. Accordingly, it is possible to use very flexible and economical materials for the manufacture of the receptacle. Second, this reduces the amount of material used to the minimum, which has a positive ecological impact. Other objects and advantageous aspects of the invention will be apparent from the claims and the description, as well as from the accompanying drawings, in which: Figure 1 is a plan view of a receptacle according to the invention; Figure 2 is a plan view of a part of the receptacle of the previous figure; - Figure 3 is a perspective view of the receptacle of the previous figure; Figure 4 is a plan view of a receptacle according to a second embodiment of the invention; and - Figure 5 is a plan view of a series of receptacles manufactured from a sheet of flexible material, according to the invention. With reference to Figure 1, a receptacle 1, according to one embodiment of the invention, includes two walls of flexible material 15, 16, connected together by welding or assembled with glue 2, which form the outline of the receptacle 1. The two walls of the receptacle are advantageously formed from a sheet of flexible material bent over itself in order to form the two walls. The two walls can also be formed from two separate sheets of flexible material. The assembly seam 2, in the form of a weld, also delimits a pouring nozzle 3 located in a corner of the receptacle with a sharp angle. Therefore, the moldboard nozzle is formed from the same sheet of flexible material as the sheet constituting the pocket 1. The pouring nozzle includes an output spout 4 located towards the outlet of the pocket, and an outlet channel 5 open inside. inside the flexible receptacle 1. The pouring nozzle 3 can also include a release guide 20, which can be used to separate a portion of the container, thereby opening the outlet peak 4 and the channel 5 respectively. The flexible material may be, for example, a polymer material, for example a plastic such as a heat-deformable plastic, including polyethylene, polypropylene, polyvinyl chloride and polyester polymers or a mixture of polymers. Advantageously, it is also possible to use a low cost material, for example, a co-extruded material. The internal angle a of the corner of the receptacle with an acute angle shown in the drawing 2 can be between 30 ° and 88 °, for example between 50 ° and 80 °, advantageously between 60 ° and 75 °, for example around 70 ° . The acute angle of the receptacle allows a pouring nozzle to be provided, which has an efficient self-closing function, a very simple construction and manufacturing process, without requiring any cutting of the flexible walls for the formation of the pouring nozzle . An internal angle a of between 60 ° and 75 ° can be used advantageously in order to provide a self-closing function efficient while allowing the provision of a receptacle having an advantageous ratio of advantageous volume to surface area, thus optimizing the use of the raw materials. In a preferred embodiment of the invention, the receptacle includes a self-closing outlet spout as shown in Figures 1 to 4. Advantageously, the two walls 15, 16 are welded or glued together within the flexible receptacle 1, near the location in which the channel 5 opens inside the flexible receptacle to form an obstacle 6 located opposite the exit channel. The welded obstacle 6 is of elongated shape and extends between two ends that overlap with a portion of the edge weld 2 on each side of the outlet channel 5, leaving two passages 8, 8 'free in the direction of the channel 5. The length of the overlap is relatively small in relation to the total length of the edge weld 2, preferably less than 10%. Preferably, the length of the obstacle extends essentially parallel to the portions of the edge weld 2 on each side of the outlet channel, and approximately perpendicular to the general direction of the channel. The channel (5) can have a width, for example, between 5mm and 20mm, preferably between 10mm and 15mm, for example around 12mm. During the filling of the receptacle 1, the large central part of the two walls 15 and 16 forming the receptacle 1 are separated and they inflate by means of a filling spout (which is not shown and is permanently closed at the completion of the filling process), as can be seen in figure 3. During the filling of the receptacle 1, respectively during the inflation of the walls 15 and 16, two bends are created in each of the walls through the narrow passages 8 and 8 ', approximately together with the axes marked 7, 7' in Figure 1. The deformation of the walls 15 and 16 near the obstacle terminals 6, respectively of the two portions close to each wall 15 and 16 on each side of the contracted passages 8 and 8 ', create a fold approximately along the axes 7 and 7 '. The folds 7 and 7 ', also as the generally elongated obstacles 6 lie approximately together with the dashed line of the contracted area 10 shown in Figure 1, with the section of the seam 2 lying between the bent lines 7, 7', they form a portion of surface which tend to curve inwards (arc), as shown in figure 3. The arcing of the area between the folds 7, 7 ', which include the pouring nozzle, has the effect of pressing the two flexible sheets in this area against each other and thus forming a valve that blocks the flow of the liquid through the passages 8, 8 'and through the orifice of the outlet spout 4. When the flexible receptacle is placed on a flat surface, as shown in drawing 3, and a vertical force Fv is applied approximately in the large central part of the upper wall 15, then the bends 7, 7 'and the arc effect of the area between the bends 7, 7 ', which includes the pouring nozzle, tends to be more pronounced, thereby increasing the efficiency of the valve action. The accentuation of the bends 7, 7 'near the passages 8, 8' as well as the increase of the arc effect of the area between the bends 7, 7 ', with the application of the force Fv essentially perpendicular to the plane of the bends. flexible walls, effectively prevents liquid spillage when the flexible receptacle is placed in its natural position on an essentially flat surface, and even when another object is placed on top of the receptacle, it increases the pressure in the receptacles. In order to allow the flow of the liquid through the outlet peak 4, it is sufficient for the user to apply a certain pressure to the receptacle, in particular by compressing it, at least in part, in a direction Fh essentially perpendicular to the plane of the obstacle weld 6, thereby partially opening the lips near the passage or narrow passages 8, 8 '. The release of this action of understanding closes the contracted passages again and closes the receptacle again. The understanding of the receptacle in the direction Fh >; Essence perpendicular to the plane of the obstacle weld, has the effect of reducing the arc and folds 7, 7 ', while, at the same time, increasing the pressure of the liquid in the receptacle, which then causes the lips of the flexible sheets at the entrance of passages 8 and 8 'are partially opened, allowing the liquid flows out. In fact, when an FH compression force is applied approximately on the side sections of the weld seam, accompanied by the increase in pressure inside the receptacle, then a pulling force Ft and a rotation of torque FR act on the part of the seam near the outlet peak, which tends to flatten, that is, to reduce the arc of the area of the pouring nozzle between the bends 7, 7 '. The general parallelogram shape of the receptacle with the above-mentioned internal angle a, of the corner with an acute angle, allows the tensile force and torque rotation created by compressing the receptacle in the direction Fh, essentially perpendicular to the plane of the plane of the obstacle weld 6, are optimized thereby facilitating the flow of the liquid through the outlet spout 4. The position of the spout at a corner with an acute diamond-shaped angle therefore allows the user to compress the the central part of the longitudinally opposite welds of the receptacle, and the creation of an effective opening of the channel, allowing the easy flow of the liquid contained in the receptacle. Since the contracted passages 8, 8 'are very short and have a very simple geometry, the closing operation is less dependent on the properties of the liquid and the elasticity of the material constituting the package than on other types of the flexible receptacle. A particular flexible package may also contain any kind of liquid, without considering in this case the chemical compatibility of the liquid with the material that constitutes the receptacle. The flexible receptacle embodiment shown and described herein includes an obstacle 6 which defines two narrow passages 8 and 8 '. It would also be possible to provide a contact between an obstacle terminal and the portion closest to the weld 2, thus leaving only a narrow passage, then forming with a single bend in the walls 15 and 16 during the filling of the receptacle. In another embodiment, shown in Figure 4, the welded obstacle 6 'is located opposite the output spike as in the previous embodiments, except that this obstacle is in two parts and has a central passage 12. In this embodiment , the central passage 12 created in the welded obstacle allows the liquid flow in the passage of the outlet peak to increase when the user applies pressure to the receptacle in a direction essentially perpendicular to the plane of the obstacle weld. The figures show a receptacle 1 composed of a single sheet of flexible material folded on itself next to a straight edge. The receptacle 1 as shown has a weld seam together with its four edges to form the internal volume of the receptacle. It is understood that the weld together with the straight edge may be omitted. Alternatively, the receptacle can be made from two sheets of flexible material connected together by an assembly seam in the form of gluing or welding. Advantageously, a multiplicity of receptacles 1 they can be manufactured simultaneously or continuously from a large sheet of flexible material. Figure 5 shows a series of receptacles 1 made from a sheet of flexible material. In accordance with the form of the invention shown in Figure 1, the receptacles are formed by folding a sheet of flexible material on itself in order to form the two walls 15, 16 of the receptacles. The sheet of folded flexible material is then welded, for example by thermal welding, to define the edge of the receptacle around the internal volume, the nozzle with a spout, and an outlet channel connecting the outlet spout to the outlet. internal volume of the receptacle and the obstacle. The receptacles can be separated from each other simply by cutting, for example by thermal cutting. The welding and cutting steps can also be carried out simultaneously. Advantageously, the described process allows the simultaneous or continuous manufacture of a multiplicity of flexible receptacles for liquid, from a sheet of flexible material, without the creation of any waste of material, which facilitates the process of manufacture and reduces the amount of material used. The manufacturing process is simple, does not require relatively complex or expensive processes to cut around the pouring nozzle. The cut along the two rectilinear sections of the weld seam of the outer edge of the receptacle is very simple and can therefore be executed quickly, in an economical manner, by means of the machines existing industrial balers. Advantageously, through the use of simple manipulations of the material, this process allows the use of very flexible and inexpensive materials. The formation of the self-closing exit spout without the need for any cutting, nor the creation of any waste is advantageous for the use of receptacles for applications that require an aseptic environment, since the receptacles can be produced and filled without the need for the evacuation of any waste that compromises the aseptic conditions. Thus, the receptacles are useful for containing prolonged preservation products such as products treated with ultra heat (U HT).

Claims (10)

1. A flexible receptacle for liquid, comprising two walls of flexible material, the superimposed free edges of said walls which are joined by means of a peripheral weld seam to define an internal sealed volume of said receptacle, a self-sealing pouring nozzle in a corner of said receptacle comprising an exit spout located towards the outside of said receptacle, an exit channel that connects to the outlet spout to the internal volume of said receptacle, a self-closing valve comprising one or more obstacles formed by welding of the two walls and placed in said internal volume essentially opposite and close to the channel leading to the outlet peak to limit the cross section of the liquid flow passage between the internal volume and the outlet channel, leaving at least one free narrow channel, where the outlet channel is formed by welding on each side of the channel within the volume defined by the peripheral seam, said peripheral seam has a parallelogram shape having an acute angle of less than 80 °, and the pouring nozzle is located in a corner of said receptacle at an acute angle.

2. A flexible receptacle according to claim 1, characterized in that it is made from a sheet of flexible material folded on itself to compose said walls.

3. A flexible receptacle in accordance with the claim 1 or 2, characterized in that the flexible material is a polymeric material.

4. A flexible receptacle according to claim 3, characterized in that the polymeric material is a plastic formed by extrusion. A flexible receptacle according to any of claims 2 to 4, characterized in that it is formed in a juxtaposed series of several receptacles by welding and thermal cutting a sheet of flexible material. 6. A flexible receptacle according to any of the preceding claims, characterized in that the internal angle of the corner with an acute angle is between 50 ° and 80 °. 7. A flexible receptacle according to claim 6, characterized in that the internal angle of the corner with an acute angle is between 60 ° and 75 °. 8. A process for manufacturing flexible receptacles for liquid, comprising: i) overlapping two sheets of flexible material or folding on itself a sheet of flexible material in order to form two walls of said receptacle. ii) welding the two walls to form a weld seam defining a peripheral edge of the receptacle having a parallelogram shape with an acute angle of less than 80 °. iii) welding a pouring nozzle located in a corner of the receptacle at an acute angle, which has an output peak located outwardly of said receptacle, and an outlet channel connecting the outlet spout to the internal volume of said receptacle wherein the outlet channel is formed by welding a seam on each side of the channel within the volume defined by the peripheral seam. , and iv) welding one or more obstacles positioned in said internal volume essentially opposite and close to the channel leading to the outlet peak, to limit the cross section of the flow passage of the liquid between the internal volume and the outlet channel, leaving free at least one narrow channel. 9. A process according to claim 8, wherein several receptacles are manufactured from a single sheet in a juxtaposed manner, with all the receptacles being separated from each other by thermal cutting. 10. A process according to claim 9, wherein the welding and cutting steps are carried out simultaneously. RESU M IN OF THE I NVENTION A flexible receptacle for liquid, comprising two walls (15, 16) of a flexible material, the overlapping free edges of said walls which are joined by means of a peripheral weld seam (2) to define an internal sealed volume of said receptacle, a self-sealing pouring nozzle (3) in a corner of said receptacle comprising an exit spout (4) located outwardly of said receptacle, an exit channel (5) that connects the exit spout to the internal volume of said receptacle, a self-closing valve comprising one or more obstacles (6) formed by welding the two walls and placed in said internal volume essentially opposite and close to the channel leading to the outlet peak to limit the cross section of the passage of liquid flow between the internal volume and the outlet channel, leaving free at least one narrow channel, where the outlet channel is formed by means of a weld on each side of the channel within the volume defined by the peripheral seam said peripheral seam is in the form of a parallelogram having an acute angle of less than 80 °, and the pouring nozzle is placed in a corner of said receptacle at an acute angle.