MXPA01013183A - Conformable container liners. - Google Patents

Abstract

The present invention provides a container liner (10) comprising at least one sheet of flexible sheet material (52) assembled to form a semi-enclosed container having an opening defined by a periphery (28). The sheet material (52) has a preferential elongation (80) axis which permits the liner (10) to expand in response to forces exerted by contents within the liner (10) to provide an increase in volume of the liner (10) and conform the liner (10) to the interior volume of a container (31).

Description

CONFORTABLE LINES FOR CONTAINERS FIELD OF THE INVENTION The present invention relates to liners of the type that are commonly used for lining drums, boxes and other types of containers.

BACKGROUND OF THE INVENTION Liners, particularly those made from comparatively inexpensive polymeric materials, have been used extensively to line the inside of drums, boxes and other types of containers in order to protect containers against their contents and / or to protect the contents against contamination due to contact with the container. The liners have also been used to provide a barrier to prevent spillage, particularly of liquid products and granular or powdered products, such as cereal. As used herein, the term "flexible" is used to refer to materials that are capable of flexing or bending, especially repeatedly, such that they are manageable and deformable in response to externally applied forces. Accordingly, the term "flexible" is substantially opposed as to the meaning of the terms inflexible, rigid or non-deformable. Therefore, materials and structures that are flexible can be altered in form and structure to adapt to external forces and conform to the shape of the objects that are put in contact with them, without losing their integrity. Liners of the type that are commonly available are typically formed from materials that have consistent physical properties through the liner structure, such as elastic, tensile and / or elongation properties. With these liners, it is often difficult to provide liners that fit precisely to the dimensions and volume of the interior of the container. The excess material of the liner is grouped or gathered within the container, particularly in the lower portion where the corners or edges frequently intersect, leading to the creation of an air space trapped between the liner and the container. In addition, the linings that are too small in the same way lead to a low utilization of the interior space of the container. Accordingly, it is desired to provide a liner that is able to conform intimately to the volume and / or dimensions of the inside of the container in use.

SUMMARY OF THE INVENTION The present invention provides a liner for a container comprising at least one leaf of a flexible sheet material that is assembled to form a semi-closed container having an opening defined by a periphery. The sheet of material has a preferential elongation axis which allows the liner to expand in response to the forces exerted by the content placed inside the liner, to provide an increase in the volume of the liner and shape the liner to the interior volume of the container.

BRIEF DESCRIPTION OF THE FIGURES While the specification concludes with the claims clearly indicating and claiming the present invention, it is believed that the present invention can be better understood from the following description in combination with the figures of the accompanying drawings, in which: wherein the reference numbers are retained the same when dealing with identical elements or with similar functions, and wherein: Figure 1 is a schematic view of a liner of a container in accordance with the present invention in its closed and empty condition; Figure 2 is a perspective view of the liner of Figure 1 in a container such as a drum; Figure 3 is an elevational view of the liner of Figure 1 in a container such as a bottle; Figure 4 is a perspective view of a container such as a cereal box suitable for use with a liner, such as the liner of Figure 1; Figure 5A, is a segmented perspective illustration of the polymeric film material suitable for the container liners of the present invention, in a substantially unstressed condition; Figure 5B, is a segmented perspective illustration of the polymeric film material suitable for the container liners according to the present invention, in a partially tensioned condition; Figure 5C, is a segmented perspective illustration of the polymeric film material suitable for the container liners according to the present invention, in a condition of higher tension; Figure 6 is an illustration of a schematic view of another embodiment of a sheet of material useful in the present invention; and Figure 7 is an illustration of a schematic view of a polymeric weft material of Figure 6, in a partially tensioned condition similar to the description of Figure 5B.

DETAILED DESCRIPTION OF THE INVENTION CONSTRUCTION OF CONTAINER LINER: Figure 1 describes a currently preferred embodiment of a liner 10 for container according to the present invention. In the embodiment described in Figure 1, the container liner 10 includes a body 20 formed from a piece of a flexible sheet of material, folded over itself along the fold line 22 and attached to itself. along the side tie lines 24 and 26, to form a semi-closed container having an opening along the edge 28. The liner 10 may also include an optional closure means 30 located adjacent the edge 28 to seal the edge 28 and form a container or container totally closed. The liners, like the liner 10 of Figure 1, can also be constructed from a continuous tube of a sheet of material and, in this way, the lateral joining lines 24 and 26 are eliminated and the lower joining line is replaced. by the fold line 22. The liner 10 is suitable for containing and protecting a wide variety of materials and / or objects contained within the body of the liner. Figure 1 shows a variety of regions that extend along the surface of the liner. The regions 40 comprise rows of deeply embossed deformations in the flexible sheet of the material of the body 20, while the regions 50 comprise interposed regions without deforming. As shown in Figure 1, the undeformed regions have axes extending through the body material of the liner in a direction substantially parallel to that of the plane (axis when in a closed condition) of the open edge 28, which in the configuration shown, are also substantially parallel to the plane or axis defined by the lower edge 22. In accordance with the present invention, the body portion 20 of the liner 10 comprises a flexible sheet of material having the ability to elongate elastically to adapt to the forces exerted outward by the content that is introduced into the liner, inside the external container or container, in a combination with the ability to confer additional resistance to elongation, before the extendable limits are reached of the material. This combination of properties allows the liner to initially expand easily in response to external forces exerted by the content placed within the liner, by controlled elongation in respective directions. These elongation properties increase the internal volume P1414 of the liner by expanding the length of the bag material. In addition, although it is currently preferred to substantially build the entire body of the liner from a sheet of material having the structure and characteristics of the present invention, it may be desirable under certain circumstances to provide these materials only in one or more portions or zones. of the lining body, instead of its entirety. For example, a web of this material having the desired orientation of elasticity can be provided to form a complete circular band around the body of the liner to provide a more localized elastic property. Alternatively, a region of this material may be provided wherein the liner approaches the joining of the sides or corners of the container, such as when the bottom of a drum is attached to the side wall. Figure 2 describes a liner like the liner 10 of Figure 1, which is used in a container 31 such as a drum for liquid or powder products. In this configuration, the liner is folded over the mouth of the container to facilitate filling, after which the liner can be secured with a closure system of any suitable and conventional design, or can be sealed along the same container by use of a lid P1414 or cover of any conventional design. Figure 3 similarly describes a liner 10 used in a container such as a bottle, more particularly a baby bottle 32. Figure 4 describes a container in the form of a box, such as a cereal box 33, which can create a liner 10 therein to contain and preserve a product such as cereal. Materials suitable for use in the present invention, as described hereinafter, are believed to provide additional benefits in terms of a reduced contact area with the trash can or other container, which aids in liner removal after to place the content inside. The three-dimensional nature of the sheet of material coupled with its elongation properties also provides enhanced resistance to tearing and punctures and improved visual, tactile and auditory impression. The elongation properties also allow the liners to have a higher capacity per unit of material used, which improves the "mileage" of the linings. Therefore, smaller liners can be used than those of conventional construction for a given application.

P1414 REPRESENTATIVE MATERIALS; To better illustrate the structural characteristics and the performance advantages of the liners of the container according to the present invention, FIG. 5A provides a highly enlarged partial perspective view of a segment of the material sheet 52, suitable for forming the body 20 of the liner. as described in Figures 1-2. Materials such as those illustrated and described herein, as they are suitable for use in accordance with the present invention, as well as the methods for making and characterizing it, are described in greater detail in U.S. Pat. jointly assigned No. 5,518,801, granted to Chappell, et al. on May 21, 1996, of which his description is incorporated herein for reference. Referring to Figure 5A, material sheet 52 includes a "deformable network" of different regions. As used herein, the term "deformable network" refers to a group of interconnected and interrelated regions that are capable of extending to some. useful degree in a predetermined direction, which gives the sheet of material a behavior similar to elastic in response to an applied elongation and subsequently released. The deformable network includes at least a first region 64 and a P1414 second region 66. The material sheet 52 includes a transition region 65 which is located at the interconnection between the first region 64 and the second region 66. The transition region 65 exhibits complex combinations of the behavior of both the first region and the second region. It is recognized that each embodiment of these sheets of materials suitable for use in accordance with the present invention has a transition region; however, these materials are defined by the behavior of the sheet of material in the first region 64 and the second region 66. Therefore, the resulting description concerns the behavior of the material sheet in the first regions and in the second regions only, because it is not dependent on the complex behavior of the sheet of material in the transition regions 65. The sheet of material 52 has a first surface 52a and a second opposing surface 52b. In the preferred embodiment shown in Figure 5A, the deformable network includes a variety of first regions 64 and a diversity of second regions 66. The first regions 64 have a first axis 68 and a second axis 69, wherein the first axis 68 is preferably longer than the second axis 69. The first axis 68 of the first region 64 is substantially parallel to the P1414 longitudinal axis "L" of the material sheet 52, while the second axis 69 is substantially parallel to the transverse axis "T" of the sheet of material 52. Preferably, the second axis of the first region, the width of the first region, is approximately 0.01 inches to 0.5 inches, and more preferably 0.03 inches to 0.25 inches. The second regions 66 have a first axis 70 and a second axis 71. The first axis 70 is substantially parallel to the longitudinal axis of the sheet of material 52, while the second axis 71 is substantially parallel to the transverse axis of the sheet material 52. Preferably, the second axis of the second region, the width of the second region, is from about 0.01 inches to 2.0 inches, and more preferably from 0.125 inches to 1.0 inches. In the preferred embodiment of Figure 5A, the first regions 64 and the second regions 66 are substantially linear and extend continuously in a direction substantially parallel to the longitudinal axis of the sheet of material 52. The first region 64 has a coefficient of elasticity The and cross-sectional area Al. The second region 66 has a coefficient of elasticity E2 and a cross-sectional area A2. In the illustrated mode, the sheet of material 52 P1414 has been "shaped" such that the sheet of material 52 exhibits a resistive force along an axis, which in the case of the illustrated embodiment is substantially parallel to the longitudinal axis of the frame, when subjected to a axial elongation applied in a direction substantially parallel to the longitudinal axis. As used herein, the term "shaped" refers to the creation of a desired structure or geometry on a sheet of material that substantially retains the desired structure or geometry when it is not subjected to any elongation or externally applied force. A sheet of material of the present invention is comprised of at least a first region and a second region, wherein the first region is visually distinct from the second region. As used herein, the term "visually distinct" refers to the characteristics of the sheet of material that are readily distinguishable to the normal eye with the naked eye, when the sheet of material or the objects containing the sheet of material is they submit to normal use. As used herein, the term "surface travel distance" refers to a measurement along the topographic surface of the region in question and in a direction substantially parallel to an axis. The method for determining the distance of the surface travel of the respective regions can be found in P1414 the Methods of Analysis of the Patent section of Chappell et al previously incorporated and referred to above. The methods for forming these sheets of useful materials of the present invention include unrestricted, embossing by plates or rollers that coincide with each other, thermoforming, hydraulic formation at high pressure or molding. While the total portion of the web 52 has been subjected to a shaping operation, the present invention can also be practiced by subjecting to forming only a portion thereof, for example, a portion of the material comprising the body 20 of the bag, as described in detail below. In the preferred embodiment shown in the Figure 5A, the first regions 64 are substantially planar. That is, the material within the first region 64 is substantially in the same condition before and after the shaping step experienced by the frame 52. The second regions 66 include a variety of raised elements similar to ribs 74. The elements Similar ribs can be embossed, with embossing, or a combination of these. The rib-like elements 74 have a first or main axis 76, which is substantially parallel to the transverse axis of the frame 52 and a secondary or minor axis 77 that is substantially parallel to the longitudinal axis of the frame 52. The parallel length the first axis 76 of the rib-like elements 74 is at least equal to or preferably greater than the parallel length of the second axis 77. Preferably, the ratio of the first axis 76 to the second axis 77 is at least 1: 1 or more, and more preferably at least 2: 1 or more. The rib-like elements 74 in the second region 66 can be separated from one another by means of non-conformed areas. Preferably, the rib-like elements 74 are adjacent to each other and are separated by an unformed area of less than 0.10 inches, as quantified perpendicular to that of the main shaft 76 of the rib-like elements 74, and preferably superlative, the rib-like elements 74 are contiguous and essentially without non-conformed areas between them. The first region 64 and the second region 66 each have a "projected travel distance". As used herein, the term "projected travel distance" refers to the distance of a shadow from a region that is projected by a parallel light. The projected travel distance of the first region 64 and the P1414 projected travel distance of the second region 66, are equal to each other. The first region 64 has a surface travel distance, Ll, less than the surface travel distance, L2, of the second region 66 as it is quantified topographically in a direction parallel to the longitudinal axis of the frame 52, while the frame is in an unstressed condition. Preferably, the surface travel distance of the second region 66 is at least 15% greater than that of the first region 64, more preferably at least 30% greater than that of the first region, more preferably at least 70% greater than the first region. In general, the greater the distance of the surface travel of the second region, the greater the elongation of the weft before reaching the force barrier. Suitable techniques for quantifying the distance of the surface travel of the materials are described in the Chappell et al. previously incorporated and referred to previously. Sheet material 52 exhibits a modified "Poisson's lateral contraction effect" substantially less than that of another identical base fabric of a composition of similar material. The method for determining the Poisson's lateral contraction effect of a material can be found in the Methods of Analysis of the Patent section of Chappell et al. previously incorporated and referred to previously. Preferably, the Poisson's lateral contraction effect of the frames suitable for use in the present invention is less than 0.4 when the frame is subjected to an elongation of about 20%, preferably the frames exhibit a Poisson's lateral contraction effect of less than 0.4. when the web is subjected to an elongation of approximately 40, 50 and even 60% elongation. More preferably, the Poisson's lateral contraction effect is less than 0.3 when the frame is subjected to an elongation of 20, 40, 50 or 60%. The Poisson's lateral contraction effect of these frames is determined by the amount of the material of the frame that is occupied by the first and second regions, respectively. As the area of the sheet of material occupied by the first region increases, the Poisson's lateral contraction effect also increases. Conversely, as the area of the material sheet occupied by the second region increases, the Poisson's lateral contraction effect decreases. Preferably, the percentage of the area of the material sheet occupied by the first area is from 2% to 90%, more preferably from 5% to 50%. The sheets of materials of the prior art P1414 having at least one layer of an elastomeric material, generally have a large Poisson lateral contraction effect, i.e. they "shrink" as they elongate in response to an applied force. Weft materials useful in accordance with the present invention can be designed to substantially moderate or eliminate the Poisson's lateral contraction effect. For material sheet 52, the direction of the applied axial elongation, D, which is indicated by the arrows 80 in Figure 5A, is substantially perpendicular to that of the first axis 76 of the rib-like elements 74. Elements similar to ribs 74 are capable of unfolding or geometrically deforming from a direction substantially perpendicular to that of their first axis 76 to allow extension in the web 52. Referring to Figure 5B, as the web of material sheet 52 is subjected to an applied axial, D, which is indicated by the arrows 80 in Figure 5B, the first region 64 having a smaller surface travel distance, Ll, provides the greater part of the initial strength of resistance, Pl, as a result of a deformation at the molecular level to the applied elongation. In this step, the rib-like elements 74 in the second region 66, undergo a geometric deformation P1414 or a split and offer a minimum resistance to the elongation applied. In transition to the next step, the rib-like elements 74 are being aligned with (i.e., have coplanarity with) the applied elongation. That is, the second region exhibits a change from a geometric deformation to a deformation at the molecular level. This is the beginning of the force barrier. In the step seen in Figure 5C, the rib-like elements 74 in the second region 66 are substantially aligned with (ie, they are in coplanarity with) the plane of the applied elongation (ie, the second region has reached its limit of geometric deformation) and begin to resist greater elongation by means of a deformation at the molecular level. The second region 66 now contributes, as a result of the deformation at the molecular level, to a second resistive force, P2, to an elongation which is then applied. The elongation-resistant forces provided by both the deformation at the molecular level of the first region 64 and by the deformation at the molecular level of the second region 66, provide a total resistive force, PT, which is greater than the resistive force that is provided by the deformation at the molecular level of the first region 64 and the geometric deformation of the second region 66. The resistive force Pl is substantially higher P1414 that the resistant force P2, when (Ll + D) is less than L2. When (Ll + D) is less than L2, the first region provides the initial resistive force Pl, which generally satisfies the equation: Pl = (Al X El x D) Ll When (Ll + D) is greater than L2, the First and second regions provide a combined total resistive force, PT, before the applied elongation, D, which generally satisfies the equation: PT = (Al x D x) + (A2 x E2 x I ~ L1 + D - L21) Ll L2 The maximum elongation that occurs while in the stage corresponding to Figures 5A and 5B, before reaching the stage described in Figure 5C, is the "elasticity available" of the material of the formed web. The available elasticity corresponds to the distance over which the second region undergoes geometric deformation. The range of elasticity available can vary from 10% to 100% or more, and can be controlled fairly by the extent to which the distances of the surface travel L2 in the second region exceeds the distance of surface travel Ll in the first region and the composition of the base film. The term elasticity available, does not intend to imply a P1414 limit to the elongation at which the frame of the present invention can be subjected, since there are applications where an elongation beyond the elasticity available is desired. When the sheet of material is subjected to an applied elongation, the sheet of material exhibits a behavior similar to the elastic as it is extended in the direction of the applied elongation and is returned to its substantially non-tense condition once the elongation has been removed applied, unless the sheet of material extends beyond the point of deformation. The material sheet is capable of experiencing various cycles of applied elongation without losing its ability to recover substantially. Consequently, the weft is able to return to its substantially non-tense condition once the applied elongation is removed. While the sheet of material can be easily and reversibly extended in the direction of the applied axial elongation, in a direction substantially perpendicular to that of the first axis of the rib-like elements, the weft material does not extend so easily in one direction substantially parallel to the first axis of the rib-like elements. The formation of rib-like elements allows rib-like elements to be geometrically deformed P1414 in a direction substantially perpendicular to that of the first axis or main axis of the rib-like elements, whereas deformation is required substantially at the molecular level to extend in a direction substantially parallel to that of the first axis of the rib-like elements. The amount of applied force that is required to extend the weft is dependent on the composition and cross-sectional area of the material sheet and the width and spacing of the first regions, with the first narrower and more separated regions with greater space requiring lower applied extension forces to achieve the desired elongation for a composition in a given cross-sectional area. The first axis, (i.e., the length) of the first regions is preferably greater than the second axis, (i.e., the width) of the first regions with a preferred length-to-width ratio of about 5: 1 or more. The depth and frequency of the rib-like elements can also be varied to control the available elasticity of a weft of a sheet of material suitable for use in accordance with the present invention. The available elasticity is increased if it is for a determined frequency of the rib-like elements, since the height or the degree of formation conferred to the rib-like elements increases. In a similar way, the available elasticity increases if it is for a certain height or degree of formation, the frequency of the elements similar to ribs increases. There are various functional properties that can be controlled by applying these materials to the flexible liners of the present invention. The functional properties are the resistant forces exerted by the sheet of material against an applied elongation and the available elasticity of the sheet of material before the force barrier is reached. The resistive force exerted by the sheet of material against an applied elongation is a function of the material (eg, composition, molecular structure and orientation, etc.) and the cross-sectional area and the percentage of the projected surface area of the material. sheet of material that is occupied in the first region. The greater the percentage of the area of coverage of the sheet of material in the first region, the greater is the strength that the weft exerts against an elongation applied to a given composition of material and a certain cross-sectional area. The percentage coverage of the material sheet in the first region is determined in part, if not entirely, by the widths of the first regions and the spacing between the first adjacent regions. The available elasticity of the weft material is determined by the surface travel distance of the second region. The distance of surface travel of the second region is determined, at least in part by the separation of the rib-like element, the frequency of the rib-like elements and the depth of the formation of the rib-like elements as quantified. perpendicular to the plane and the material of the frame. In general, the greater the distance of surface travel of the second region, the greater the available elasticity of the material of the web. As discussed above with respect to Figures 5A-5C, material sheet 52 initially exhibits a certain resistance to elongation provided by the first region 6, while the rib-like elements 74 of the second region 66, experience a geometric movement. As the rib-like elements undergo a transition to the plane of the first regions of the material, an increased resistance to elongation is exhibited, while the entire sheet of the material then undergoes a deformation at the molecular level. Accordingly, the sheets of materials of the type described in Figures 5A-5C and those described in the Chappell et al. Patent. previously incorporated and referred to previously, provide the performance advantages of the present invention when formed in flexible liners of the present invention. An additional benefit realized by using the aforementioned sheets of materials in the construction of flexible liners according to the present invention, is the increase in the tactile and visual attractiveness of these materials. Polymeric films that are commonly used to form these flexible polymer bags are typically comparatively thin in nature and often have a smooth, glossy surface finish. While some manufacturers use a low degree of embossing or other texturing of the surface of the film, at least one side that faces out of the finished bag, the bags that are made of these materials still tend to exhibit a slippery and light touch impression. Thin materials coupled with a substantially two-dimensional surface geometry also tend to leave the consumer with an exaggerated impression of thinness and a noticeable lack of durability, of these bags P1414 flexible polymer. In contrast, sheets of materials useful in accordance with the present invention such as those described in Figures 5A-5C, exhibit a three-dimensional profile in the cross section where the sheet of material is located (in a non-taut condition). deformed outside the predominant plane of the material sheet. This provides an additional surface area for gripping and dissipates the glare normally associated with the substantially flat and smooth surfaces. The three-dimensional rib-like elements also provide a "cushioned" tactile impression when the bag is held in the hand, which also contributes to a desirable tactile impression that is contrary to that presented by conventional bag materials and provides enhanced perception of thickness and durability. The additional texture also reduces the noise associated with certain types of film materials, leading to an intensified auditory impression. Suitable mechanical methods for forming the base material in a web of a sheet of material suitable for use in the present invention are well known in the art and described in the Chappell et al. Patent. previously mentioned and in the patent of E.U.A. ceded jointly with number 5,650,214, granted on the 22nd P1414 July 1997 to Anderson et al., Of which their descriptions are incorporated herein for reference. Another method for forming the base material in a web of a sheet of material suitable for use in the present invention is vacuum forming. An example of vacuum forming is described in the U.S. Patent. yielded jointly with the number 4,342,314, granted to Radel et al., on August 3, 1982. Alternatively, the formed web of the material sheet can be hydraulically shaped as shown in the U.S. Patent. assigned jointly with No. 4,609,518, granted to Curro et al., on September 2, 1986. The descriptions of each of the above patents are incorporated herein for reference. The shaping method can be achieved in a static mode, wherein a discrete portion of a base film is deformed at a time. Alternatively, the shaping method can be achieved using a dynamic and continuous press to intermittently contact the moving web and form the base material in a shaped web material of the present invention. These and other suitable methods for shaping the weft material of the present invention are described in greater detail in the Chappell et al. , previously incorporated and referred to previously. The flexible liners can be manufactured from a sheet of shaped material or, alternatively, the flexible liners can be manufactured and then subjected to the methods for forming the sheet of material. Referring now to Figure 6, other patterns for the first and second regions may also be employed, in the manner of sheets of materials 52 suitable for use in accordance with the present invention. The sheet of material 52 is shown in Figure 6 in its substantially unstressed condition. The sheet of material 52 has two center lines, a longitudinal center line, which is also referred to hereinafter as axis, line, or "L" direction and a transverse or lateral center line, which is also referred to hereinafter as axis, line, or direction "T". The transverse centerline "T" is generally perpendicular to the longitudinal centerline "L". The materials of the type described in Figure 6 are described in greater detail in the aforementioned Anderson et al. Patent. As noted above with respect to Figures 5A-5C, material sheet 52 includes a "deformable network" of different regions. The deformable network P1414 includes a diversity of first regions 60 and a diversity of second regions 66 that are visually distinct from each other. The material sheet 52 also includes transition regions 65 which are located at the interconnection between the first regions 60 and the second regions 66. The transition regions 65 exhibit complex combinations of the behavior of both the first region and the second region, such as It was noted before. The sheet of material 52 has a first surface, (the one facing towards the observer in Figure 6) and a second opposing surface (not shown). In the preferred embodiment shown in Figure 6, a deformable network includes a variety of first regions 60 and a diversity of second regions 66. A portion of the first regions 60, indicated generally as 61, are substantially linear and extend in a first direction. The rest of the first regions 60, indicated generally as 62, are substantially linear and extend in a second direction, which is substantially perpendicular to the first direction. While it is preferred that the first direction be perpendicular to the second direction, other angular relationships between the first direction and the second direction may be suitable as long as the first regions P1414 61 and 62 cross each other. Preferably, the angles between the first and second directions range from 45 ° to 135 °, with 90 ° being the most preferred. The intersection of the first regions 61 and 62 forms a boundary indicated by the virtual line 63 in Figure 6, which completely surrounds the second regions 66. Preferably, the width 68 of the first regions 60 is 0.01 inches to 0.5 inches, and more preferably 0.03 inches to 0.25 inches. However, other width dimensions for the first regions 60 may also be suitable. Because the first regions 61 and 62 are perpendicular to each other and with equal spacing, the second regions have a square shape. However, other shapes for the second region 66 are suitable and can be achieved by changing the spacing between the first regions and / or aligning the first regions 61 and 62 with respect to one another. The second regions 66 have a first axis 70 and a second axis 71. The first axis 70 is substantially parallel to the longitudinal axis of the material of the weft 52, while the second axis 71 is substantially parallel to the transverse axis of the weft material 52. The first regions 60 have a coefficient of elasticity E2 and a transversal area A2. In the embodiment shown in Figure 6, the first regions 60 are substantially planar. That is, the material within the first regions 60 is substantially in the same condition, before and after the forming step experienced by the frame 52. The second regions 66 include a plurality of raised elements similar to ribs 74. The elements similar to Ribs 74 can be embossed, embossed in a low relief or a combination of these. The rib-like elements 74 have a first axis or main axis 76 that is substantially parallel to the longitudinal axis of the frame 52 and a secondary or minor axis 77 is substantially parallel to the transverse axis of the frame 52. The elements similar to ribs 74 in the second region 66 can be separated from each other by non-conformed areas, essentially with low relief engraving or not embossed, or simply formed as separation areas. Preferably, the rib-like elements 74 are adjacent to each other and are separated by an unformed area of less than 0.10 inches, as quantified perpendicular to the main axis 76 of the rib-like elements 74, more preferably, similar elements. at 74 ribs they are contiguous and essentially do not have areas without forming between them.

P1414 The first regions 60 and the second regions 66 each have a "projected travel distance". As used herein, the term "projected travel distance" refers to the length of a shadow of a region that is projected due to a parallel light. The projected travel distance of the first region 60 and the projected travel distance of the second region 66 are equal to each other. The first region 60 has a surface travel distance, Ll, less than the surface travel distance, L2, of the second region 66 as measured topographically in a parallel direction while the frame is in an unstressed condition. Preferably, the surface travel distance of the second region 66 is at least 15% greater than that of the first region 60, more preferably at least 30% greater than that of the first region, and preferably superlative of at least approximately 70% greater than that of the first region. In general, the larger the surface travel distance of the second region, the greater the elongation of the web before reaching a force barrier. For material sheet 52, the direction of an applied axial elongation, D, indicated by arrows 80 P1414 in Figure 6 is substantially perpendicular to that of the first axis 76 of the rib-like elements 74. This is due to the fact that the rib-like elements 74 are capable of unfolding or geometrically deforming in a direction substantially particular to the of its first axis 76 to allow an extension in the frame 52. Referring now to Figure 7, while the frame 52 is subjected to an applied axial elongation, D, indicated by the arrows 80 in Figure 7, the first regions 60 they have the shortest surface travel distance, Ll, and they provide most of the initial resistant force, Pl, as a result of a deformation at the molecular level, before the applied elongation corresponding to stage I. While in stage I, the rib-like elements 74 in the second regions 66, undergo geometric deformation, or a split and offer minimal resistance to the applied elongation. In addition, the shape of the second regions 66 changes as a result of the movement of the reticulated structure, formed by the first regions 61 and 62 that intersect. Accordingly, while the frame 52 is subjected to the applied elongation, the first regions 61 and 62 undergo geometric deformation or splitting, and thus change P1414 the shape of the second regions 66. The second regions extend or elongate in a direction parallel to the direction of the applied elongation, and collapse or shrink in a direction perpendicular to the direction of the applied elongation. In addition to the aforementioned elastic-like properties, a sheet of material of the type described in Figures 6 and 7 provides a smoother and more fabric-like texture and appearance and is quieter during use. Various compositions suitable for building the flexible liners of the present invention include substantially impermeable materials such as polyvinyl chloride (PVC), polyvinylidene chloride (PVDC), polyethylene (PE), polypropylene (PP), aluminum foil, coated paper (waxed) , etc.), and uncovered, non-woven and coated textiles, etc., and substantially permeable materials such as cotton fabric, meshes, fabrics, nonwovens, or perforated or porous films, regardless of whether they are predominantly two-dimensional in nature or formed in three-dimensional structures. These materials may comprise a single composition or layer, or may be a structure composed of various materials. Once the desired sheets of materials are made in any desired and proper form, and that P1414 comprise all or part of the materials to be used for the body of the liner, the liner can be constructed in any known and suitable manner, such as those known in the art to make these liners in a commercially available form. The heat sealing, mechanical sealing or adhesive technologies can be used to join the various components or elements of the liner to themselves or to each other. In addition, the bodies of the liners can be thermoformed, blown or molded instead of using bending or joining techniques to build the bodies of the liners from a weft or sheet of the material.

REPRESENTATIVE CLOSURES; Closures of any design and configuration suitable for the intended application can be used to construct the container liners according to the present invention. For example, sliding type closures, movable lugs or tabs, interlock or twist-and-tie fasteners, adhesive-based fasteners, mechanical interlocking seals with or without slide-type fasteners, tapes or fasteners Removable deeds of lining composition, thermal seals or any other suitable closure can be used. These closures are well known in the art since they are methods for making and applying them to flexible bags similar in structure to the container liners of the present invention. While the particular embodiments of the present invention have been illustrated and described, it is obvious to those skilled in the art that various changes or modifications can be made without departing from the spirit and scope of the invention. Therefore, it is intended to cover in the appended claims all changes and modifications that are within the scope of this invention.

P1414

Claims (11)

1. CLAIMS; A container liner characterized by at least one sheet of flexible material assembled to form a semi-enclosed container having an opening defined by a periphery, this sheet of material has a preferential elongation axis that allows the liner to expand in response to the forces exerted by the Content placed inside the liner, to provide an increase in the volume of the liner and shape the lining to the interior volume of the container. The container liner according to claim 1, wherein the container liner includes a closure means for sealing the opening and converting a semi-closed container into a closed container. The container liner according to any of the preceding claims, wherein the sheet of material includes a first region and a second region comprising the same material composition, the first region undergoes a deformation substantially at the molecular level and the second region undergoes a deformation initially a substantially geometric deformation when the sheet of material is subjected to an elongation applied along at least one axis. 4. The container liner according to claim 3, wherein the first region and the second region P1414 region are visually distinct from each other. The container liner according to claims 3 or 4, wherein the second region includes a plurality of rib-like high relief elements. 6. The container liner according to claims 3, 4 or 5, wherein the first region is substantially free of rib-like elements. The container liner according to claim 5 or 6, wherein the rib-like elements have a major axis and a minor axis 8. The container liner according to any of the preceding claims, wherein the sheet of material exhibits minus two significantly different stages of forces resistant to axial elongation applied along at least one axis, when subjected to elongation applied in a direction parallel to the axis, in response to a force applied externally in this container liner when it is formed in a closed container; this sheet of material comprises: a deformable network including at least two visually distinct regions, one of the regions being configured to exhibit a resistive force in response to axial elongation applied in a direction parallel to the axis P1414 before a substantial portion of the other of the regions develops a significant resistive force versus the applied axial elongation; at least one of the regions has a surface travel distance that is greater than that of the other regions when quantized parallel to the axis, while the material sheet is in an unstressed condition; the region exhibits a longer surface travel distance and includes one or more rib-like elements, the sheet of material exhibits a first strength resistant to elongation applied until the elongation of the sheet of material is large enough to cause a a substantial portion of the region has a longer surface travel distance to enter the plane of the applied axial elongation, while the material sheet exhibits a second force resistant to another applied axial elongation; This sheet of material exhibits a total strength strength greater than the strength strength of the first region. The container liner according to any of claims 1-7, wherein the sheet of material exhibits at least two stages of forces resistant to an applied axial elongation, D, along at least one axis when subjected to an axial elongation applied along the axis in response to a force externally P1414 applied on the container liner when it is formed in a closed container; the sheet of material comprises: a deformable network of visually distinct regions, this deformable network includes at least a first region and a second region, the first region has a first distance of surface travel, Ll, when quantified in parallel to the axis while, that the sheet of material is in an unstressed condition, the second region has a second distance of surface travel, L2, when quantized in parallel to the axis, while the material of the frame is in a condition without tense; the first distance of superficial travel, Ll, is smaller than the second distance of superficial travel, L2, the first region produces by itself a resistant force, Pl, in response to an applied axial, D, the second region produces by itself a resistive force, P2, in response to the applied axial elongation, D, the resistive force Pl, is substantially greater than the resistive force P2 when (Ll + D) is less than L2. The container liner according to any of the preceding claims 1-7, wherein the sheet of material exhibits a behavior similar to the elastic along at least one axis, this sheet of material comprises: at least a first region and a second P1414 region, the first region and the second region are comprised of the same material of the composition and each has an unstressed projected path distance, the first region undergoes a deformation substantially at the molecular level and the second region initially experiences a substantially geometric deformation when the weft material is subjected to an elongation applied in a direction substantially parallel to the axis in response to a force externally applied to the container liner, when formed in a closed container, the first region and the second region return substantially to its distance of travel projected without tensioning when this applied elongation is released. The container liner according to any of the preceding claims 3-10, wherein the sheet of material includes a variety of first regions and a variety of second regions comprised of the same material of the composition, a portion of these first regions extending in a first direction while the rest of the first regions extend in a direction perpendicular to that of the first direction to cross-link with each other, the first regions form a boundary that completely surrounds the second regions.