Cross-Reference to Related Applications

This application claims priority to U.S. Provisional Application Nos. 62/855,336 and 62/855,385, both filed May 31, 2019, the disclosures of which are incorporated by reference in their entirety herein.

Background

Fasteners are used in a variety of applications, including construction, machinery, medical equipment, automobile assembly, personal care products, and the textile industry. Commonly known fasteners range from rivets, snaps and buttons to hook and loop fasteners, each of which involve joining unlike components (e.g., male and female components) for assembling two articles together. Some fasteners, which are sometimes called self-mating fasteners or hook-and-hook fasteners, are composed of interlocking members that do not include male and female components. For assembling two articles together, each fastening member is attached to a surface of its respective article, and the two articles are joined together when the fastening members are mated.

Certain fasteners have been reported that include different structures on the same fastening member. See, for example, U.S. Pat. Nos. 5,586,372 (Eguchi); 5,884,374 (Clune); 6,276,032 (Nortman); and 6,546,604 (Galkiewicz). The different structures may have different shapes, sizes, or abilities to engage.

Reclosable packages can be used as containers for various consumer goods such as dry goods, food such as potato chips and cheese, animal food, lawncare products, etc. Such packages are available in a variety of shapes and sizes. Further, various reclosable packages can be multi-use containers that can maintain storage of consumer goods disposed within the packages for a desired number of openings and closings of the package. For example, a multi-use package can provide access by a user to the contents disposed within the package and then be closed to prevent the contents from spilling out of the package. These multi-use packages can include built-in fasteners that can be repeatedly opened and closed. Further, various multi-use packages can also be resealed after the first opening of the packages to keep the contents fresh and free from intrusion by various external elements such as air, moisture, and various contaminants.

Typically, reclosable packages can be made from one or more sheets or films that include one or more flexible materials. A film can be folded and sealed together to form a pouch having an interior volume and an opening through which consumer goods can be disposed within the volume. A fastener can be disposed adjacent the opening that can be repeatedly manipulated from a closed configuration to an open configuration. Some reclosable packages having self-mating fasteners have been reported. See, for example,

U.S. Pat. No. 8,641,278 (Ducauchuis) and U.S. Pat. Appl. Pub. Nos. 2006/0168776 (Dais) and

2013/0071047 (VanLoocke).

Summary

The present disclosure provides a process for making a structured fdm having at least one rib on a backing. The process results in a structured fdm with a rib having at least a continuous base portion attached to a backing and a series of notches in a portion distal from the backing. The structured fdm can be useful, for example, as a fastener. The presence of ribs can improve the ability of the fastener to seal relative to a comparative fastener that includes rows of discontinuous fastening elements on a backing but does not include ribs. The fastener can be useful, for example, as a self-mating fastener for a reclosable package.

The process includes providing a tool roll having a first groove in its outer surface . The first groove has a width of not more than 250 micrometers and a depth of at least 250 micrometers and has multiple protrusions around its peripheral surface. The process includes contacting the outer surface of the tool roll with a moldable material. The moldable material fills at least 90 percent of the depth of the first groove. The process further includes removing the structured fdm from the outer surface of the tool roll. The structured fdm comprises a rib having at least a continuous base portion attached to a first major surface of a backing and a distal portion distal from the backing. The distal portion of the rib has a series of notches corresponding to the multiple protrusions around the peripheral surface of the first groove.

In another aspect, the present disclosure provides a structured fdm made by the process described herein.

Protrusions in the grooves allow the grooves to be filled with moldable material when a relatively low-pressure nip is used in the process to make the structured fdm, and no vacuum filling is used to fill the cavities. Thus, standard, less expensive processing equipment can be used to carry out the process of the present disclosure. Unexpectedly, when the notches are absent the grooves only partially fill, providing ribs of lower height than desired.

In this application:

All headings provided herein are for the convenience of the reader and should not be used to limit the meaning of any text that follows the heading, unless so specified.

The term“comprises” and variations thereof do not have a limiting meaning where these terms appear in the description and claims. Such terms will be understood to imply the inclusion of a stated step or element or group of steps or elements but not the exclusion of any other step or element or group of steps or elements.

Terms such as "a", "an" and "the" are not intended to refer to only a singular entity but include the general class of which a specific example may be used for illustration. The terms "a", "an", and "the" are used interchangeably with the term "at least one". The phrase "comprises at least one of' followed by a list refers to comprising any one of the items in the list and any combination of two or more items in the list. The phrase "at least one of' followed by a list refers to any one of the items in the list or any combination of two or more items in the list.

As used herein, the term“or” is generally employed in its usual sense including“and/or” unless the content clearly dictates otherwise.

The term“and/or” means one or all of the listed elements or a combination of any two or more of the listed elements.

The term "machine direction" (MD) as used herein denotes the direction of a running web of material during a manufacturing process. When a strip is cut from a continuous web, the dimension in the machine direction corresponds to the length "L" of the strip. The terms “machine direction” and “longitudinal direction” may be used interchangeably. The term "cross-machine direction" (CD) as used herein denotes the direction which is essentially perpendicular to the machine direction. When a strip is cut from a continuous web, the dimension in the cross-machine direction corresponds to the width "W" of the strip. Accordingly, the term“width” typically refers to the shorter dimension in the plane of the first surface of the backing, which is the surface bearing the rail segments and posts. As used herein the term “thickness” usually refers to the smallest dimension of the fastener, which is the dimension perpendicular to the first surface of the backing.

The term "alternating" as used herein refers to one row of rail segments being disposed between any two adjacent ribs (i.e., the adjacent ribs have only one row of rail segments between them) and one rib being disposed between any two adjacent rows of rail segments and/or one row of rail segments being disposed between any two adjacent rows of posts (i.e., the rows of posts have only one row of rail segments between them) and one row of posts being disposed between any two adjacent rows of rail segments.

The term "perpendicular" as used herein to refer to the relationship between the backing and the rail segments and/or posts includes substantially perpendicular. “Substantially perpendicular” means that the planes defined by the backing and a row of rail segments or posts can deviate from perpendicular by up to 10 (in some embodiments, up to 7.5 or 5) degrees.

The term“continuous” with reference to the base portion of the rib is relative to the length of the rail segments, which are segmented and not continuous. The continuous base portion is continuous for the length of at least five rail segments. In some embodiments, the continuous base portion is continuous for the length of the backing.

As used herein in connection with a measured quantity, the term“about” refers to that variation in the measured quantity as would be expected by the skilled artisan making the measurement and exercising a level of care commensurate with the objective of the measurement and the precision of the measuring equipment used. Herein,“up to” a number (e.g., up to 50) includes the number (e.g., 50).

All numerical ranges are inclusive of their endpoints and nonintegral values between the endpoints unless otherwise stated (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, 5, etc.). These and other aspects of the present disclosure will be apparent from the detailed description below. In no event, however, should the above summaries be construed as limitations on the claimed subject matter, which subject matter is defined solely by the attached claims, as may be amended during prosecution.

Brief Description Of The Drawings

The disclosure may be more completely understood in consideration of the following detailed description of various embodiments of the disclosure in connection with the accompanying drawings, in which:

FIG. 1 is a diagrammatic illustration of a process for making a fastener according to the present disclosure.

FIG. 2 is an enlarged cut-away perspective view of a portion of a surface of a tool roll useful in a process for making a fastener according the present disclosure.

FIG. 3A is a schematic perspective view of an embodiment of a fastener made by the process of the present disclosure.

FIG. 3B is a schematic side view of a portion of the fastener of FIG. 3A.

FIG. 3C is a schematic side view of an embodiment of a fastening system of the present disclosure in which both fastener members include the fastener of FIGS. 3A and 3B.

FIG. 4 is a schematic perspective view of another embodiment of a fastener made by the process of the present disclosure.

FIG. 5 is a schematic perspective view of another embodiment of a fastener made by the process of the present disclosure.

FIB. 6A is a schematic side view of a portion of a fastener like that shown in FIG. 5 illustrating only the rail segments and posts and also having a different cap shape.

FIG. 6B is a schematic side view of a portion of the fastener shown in FIG. 6B and can also illustrate a side view of the fastener like that shown in FIGS. 4A and 5 but having a different cap shape.

FIG. 6C is a schematic side view of a portion of the fastener shown in FIG. 6A, which side view is orthogonal to the side view shown in FIG. 6B.

FIG. 7A is a schematic side view of an embodiment of fastener made by the process of the present disclosure undergoing deformation during fastening, with strain calculated by Finite Element Modeling depicted by shading.

FIG. 7B is a schematic side view of the fastener of FIG. 7A after fastening, with residual strain calculated by Finite Element Modeling depicted by shading.

FIG. 8 is a schematic side view of a fastener with permanent plastic deformation after fastening calculated by Finite Element Modeling depicted by shading. FIG. 9 is a schematic front plan view of one embodiment of a reclosable package.

FIG. 10 is a schematic rear plan view of the reclosable package of FIG. 9.

FIG. 11 is a schematic top perspective view of the reclosable package of FIG. 9.

FIG. 12 is a schematic cross-section view of a portion of the reclosable package of FIG. 9 with an embodiment of the fastener of the present disclosure disposed in a closed configuration.

FIG. 13 is a schematic cross-section view of a portion of the reclosable package of FIG. 9 with an embodiment of the fastener of the present disclosure disposed in an open configuration with the upper seal region still intact.

FIG. 14 is a schematic cross-section view of a portion of the reclosable package of FIG. 9 with an embodiment of the fastener of the present disclosure disposed in the open configuration.

FIG. 15 is a schematic cross-section view an embodiment of the opening of the reclosable package of FIG. 9 when the fastener is in the closed configuration.

FIG. 16 is a schematic perspective view of another embodiment of a reclosable package.

FIG. 17 is a schematic front plan view of the reclosable package of FIG. 16.

FIG. 18 is a schematic perspective view of another embodiment of a reclosable package.

FIG. 19 is a schematic front plan view of the reclosable package of FIG. 18.

FIG. 20 is a perspective view of one embodiment of an apparatus and method used to form a reclosable package.

Detailed Description

An embodiment of a structured film made by the process of the present disclosure is shown in FIG. 3A. The structured film is useful, for example, as a fastener. Fastener 1 includes a backing 2 having a length (L), a width (W), and a thickness (T). Fastener 1 includes rails 24 protruding from the backing 2. In the illustrated embodiment, rails 24 protrude perpendicularly from the backing 2. Rails 24 each have a continuous base portion 30 attached to the backing 2 and an engaging portion 28 distal from the backing 2. The engaging portion 28 has a width that is greater than a width of the base portion 30, and the engaging portion 28 overhangs the base portion 30 on opposing sides. Fastener 1 also comprises ribs 26 protruding from the backing 2. In the illustrated embodiment ribs 26 protrude perpendicularly from the backing 2. In some embodiments, the rails 24 and ribs 26 alternate. The fastener 1 can have at least 2, 3, 5, or 10 of the rails 24 alternating with at least 2, 3, 5, or 10 of the ribs 26.

In some embodiments, FIG. 6B illustrates a cross-section of the fastener illustrated in FIG. 3A, in which the reference to post 6 can be replaced with reference to rib 26, reference to rail segment 4 can be replaced with reference to rail 24, and in which the cap shape is different. In some embodiments, the rails 24 have a maximum height Z1 (above the backing 2) of up to 3 millimeter (mm), 1.5 mm, 1 mm, 0.65 mm, 0.6 mm, or 0.55 mm and, in some embodiments, a minimum height of at least 0.1 mm or 0.2 mm. The height Z1 of the rails 24 can be in a range from 0.3 mm to 0.7 mm, 0.3 mm to 0.65 mm, 0.3 mm to 0.6 mm, or 0.35 mm to 0.55 mm. The thickness (Z1-Z2) of the engaging portion 28 of rails 24 can be in a range from 0.03 mm to 0.2 mm, 0.04 mm to 0.15 mm, or 0.04 mm to 0.1 mm. In some embodiments, the base portions 30 of the rails 24 have a maximum width XI of up to about 0.5 mm, 0.4 mm, 0.3 mm, or 0.2 mm and a minimum width of at least 0.05 mm, 0.1 mm, or 0.125 mm. Some useful widths XI of the base portions 30 are in a range from 0.05 mm to 0.5 mm, 0.1 mm to 0.2 mm, or 0.125 mm to 0.175 mm. Some useful cap widths X4 of the rails 24 are in a range from 0.1 mm to 0.75 mm, 0.3 mm to 0.5 mm, 0.3 mm to 0.45 mm, or 0.3 mm to 0.4 mm. Some useful cap overhang distances X6 of the rails 24 are in a range from 0.025 mm to 0.3 mm, 0.05 mm to 0.3 mm, or 0.1 m to 0.25 mm.

In some embodiments, ribs 26 useful in the fastener 1 have a maximum width X2 of up to about 0.5 mm, 0.4 mm, 0.3 mm, or 0.2 mm and a minimum width of at least 0.05 mm, 0.1 mm, or 0.125 mm. Some useful widths X2 of the ribs 26 are in a range from 0.05 mm to 0.5 mm, 0.1 mm to 0.2 mm, or 0.125 mm to 0.175 mm. In some embodiments, ribs 26 can taper from their bases to their distal tips although this is not shown in FIGS. 3A, 3B, and 3C. Since the fastener 1 is useful as a self-mating fastener, the ribs 26 generally have a height that is no greater than a height of the rails 24. In the embodiment illustrated in FIGS. 3A, 3B, and 3C, the height Z3 of the ribs 26 is less than the height of the rails 24. In some embodiments, the height Z3 of ribs 26 is up to 95, 90, 80, 75, or 70 percent of the height Z1 of the rails 24 (shown in FIG. 6B). In some embodiments, the ribs 26 have a maximum height Z3 (above the backing 2) of up to 2.85 millimeter (mm), 1.25 mm, or 1 mm and, in some embodiments, a minimum height of at least 0.08 mm or 0.16 mm. The height Z3 of the ribs 26 can be in a range from 0.2 mm to 0.6 mm, 0.3 mm to 0.5 mm, 0.3 mm to 0.4 mm, or 0.35 mm to 0.55 mm. In some embodiments, each of the ribs 26 has a height to width (Z3 to X2) aspect ratio that is at least 1.5: 1, at least 2: 1, or at least 3: 1. As shown in FIG. 3 A, notches 29 in a portion of the ribs 26 and rails 24 distal from the backing 2 can be provided by protrusions in the mold surface useful for making the fastener 1, which is described in greater detail, below.

An embodiment of a structured fdm made by the process of the present disclosure is shown in FIG. 4. The structured film is useful, for example, as a fastener. Fastener 21 includes a backing 2 having a length (L), a width (W), and a thickness (T). Fastener 21 includes rows 14 of rail segments 4. In the embodiment illustrated in FIG. 4, the rail segments 4 protrude perpendicularly from the backing 2. In some embodiments, FIG. 6B illustrates a cross-section of the fastener illustrated in FIG. 4, in which the reference to post 6 can be replaced with reference to rib 26 and in which the cap shape is different. Dimensions of rail segments 4 are also shown in FIG. 6C. Each of the rail segments 4 has a base portion 10 attached to the backing 2 and a cap portion 8 distal from the backing 2. The cap portion 8 has a cap width X4 that is greater than the width XI of the base portion 10, and the cap portion 8 overhangs the base portion 10 on opposing sides. The ratio of the cap width X4 to the width XI of the base portion 10 is typically at least 1.25: 1, 1.5: 1, or 2: 1 and can be up to 3: 1, 4: 1, or 5: 1. FIG. 6B illustrates the cap overhang distance X6. In some embodiments, the cap portion 8 overhangs the base portion 10 on all sides of base portion 10. FIG. 6C illustrates the cap overhang distance Y5, in the direction parallel to the length (L) of the fastener 21. Caps also have a cap thickness, which, if the cap is not rectilinear, is measured as a distance between a line tangent to the highest point on the cap above the backing and a line tangent to lowest point on the cap above the backing. For example, in the embodiment shown in FIG. 6B, the cap thickness is Z1 minus Z2. From the term“rows of rail segments”, it should be understood that each row 14 includes more than one rail segment 4, and the rail segments 4 are not continuous but separated from each other on the backing 2. For example, the caps 8 of the rail segments 4 in a row 14 are separated by cap-to-cap distance Y3 in the direction parallel to the length (L) of the fastener 21.

Referring again to FIGS. 6B and 6C, the base portion 10 of the rail segment 4 has a length Y 1 that is greater than the width XI of the base portion 10. In some embodiments, the ratio of the length Y1 to the width XI of the base portion 10 is at least about 1.5: 1, 2: 1, 3 : 1, 4: 1, or 5: 1, 10: 1, or 15: 1. The base portion 10 of the rail segment 4 may have a variety of cross-section shapes. For example, the cross-sectional shape of the base portion 10 may be a polygon (e.g., rectangle, hexagon, or octagon), or the cross-sectional shape of the base portion 10 may be curved (e.g., elliptical). The base portion 10 may taper from its base to its distal end. In this case and in the case of curved base portions, the ratio of the length Y1 to the width XI of the base portion 10 is measured from the longest and the widest point. As shown in FIG. 6D the length Y1 of the base portion at its longest point is about the same as the length of the cap portion.

For embodiments such as the embodiment illustrated in FIG. 6C, base portions 10 that taper from their bases to their distal ends have a sloping face and a taper angle A1 between the sloping face and the backing 2. In some embodiments, the taper angle A1 between the sloping face of the base portion 10 and the backing 2 is in a range from 91 degrees to 130 degrees, in some embodiments, in a range from 91 degrees to 125 degrees, 95 degrees to 120 degrees, 95 degrees to 115 degrees, 95 degrees to 110 degrees, 93 degrees to 105 degrees, 95 degrees to 100 degrees, 91 degrees to 105 degrees, 91 degrees to 100 degrees, 91 degrees to 99 degrees, 91 degrees to 97 degrees, or 91 degrees to 95 degrees.

Referring again to FIG. 6B, in some embodiments, the rail segments 4 have a maximum height Z1 (above the backing 2) of up to 3 millimeter (mm), 1.5 mm, or 1 mm and, in some embodiments, a minimum height of at least 0.1 mm or 0.2 mm. The height Z1 of the rail segments 4 can be in a range from 0.3 mm to 0.7 mm, 0.3 mm to 0.6 mm, or 0.35 mm to 0.55 mm. The thickness (Z1-Z2) of the cap portion 8 of rail segments 4 can be in a range from 0.03 mm to 0.3 mm, 0.04 mm to 0.15 mm, or 0.04 mm to 0.1 mm. In some embodiments, the base portions 10 of the rail segments 4 have a maximum width XI of up to about 0.5 mm, 0.4 mm, 0.3 mm, or 0.2 mm and a minimum width of at least 0.05 mm, 0.1 mm, or 0.125 mm. Some useful widths XI of the base portions 10 are in a range from 0.05 mm to 0.5 mm, 0.1 mm to 0.2 mm, or 0.125 mm to 0.175 mm. Some useful cap widths X4 of the rail segments 4 are in a range from 0.1 mm to 1.0 mm, 0.3 mm to 0.5 mm, 0.3 mm to 0.45 mm, or 0.3 mm to 0.4 mm. Some useful cap overhang distances X6 of the rail segments 4 are in a range from 0.025 mm to 0.4 mm, 0.05 mm to 0.3 mm, or 0.1 m to 0.25 mm. In some embodiments, the rail segments 4 have a maximum length Y1 of up to about 1.5 mm (in some embodiments, up to 1.25, 1.0, 0.9, or 0.8) mm and a minimum length Y1 of at least about 0.1 mm, 0.2 mm, 0.4 mm, or 0.5 mm. The length Y1 of the rail segments can be in a range from 0.1 mm to 1.5 mm, 0.2 mm to 1.0 mm, or 0.600 mm to 0.800 mm. Some useful cap overhang distances Y5 of the rail segments 4 in the length direction are in a range from 0.025 mm to 0.2 mm, 0.025 mm to 0.1 mm, or 0.04 mm to 0.075 mm. In some embodiments, the cap-to-cap distance Y3 in the direction parallel to the length (1) of the fastener 1 is up to about 0.5 mm, 0.4 mm, 0.3 mm, or 0.25 mm and at least about 0.05 mm, 0.1 mm, or 0.125 mm. Some useful cap-to-cap distances Y3 are in a range from 0.05 mm to 0.5 mm, 0.1 mm to 0.3 mm, or 0.125 mm to 0.225 mm.

As shown in FIG. 4, fastener 21 made by the process of the present disclosure also includes ribs 26 protruding perpendicularly from the backing 2. Ribs 26 typically have a continuous base portion 23 attached to the backing 2. In the embodiment illustrated in FIG. 4, the rows 14 of rail segments 4 and ribs 26 alternate. The fastener 21 can have at least 2, 3, 5, or 10 of the rows 14 of rail segments 4 alternating with at least 2, 3, 5, or 10 of the ribs 26.

In some embodiments, ribs 26 useful in the fastener 21 have a maximum width X2 of up to about 0.5 mm, 0.4 mm, 0.3 mm, or 0.2 mm and a minimum width of at least 0.05 mm, 0.1 mm, or 0.125 mm. Some useful widths X2 of the ribs 26 are in a range from 0.05 mm to 0.2 mm, 0.1 mm to 0.2 mm, or 0.125 mm to 0.175 mm. In some embodiments, ribs 26 can taper from their bases to their distal tips although this is not shown in FIG. 5. Since the fastener 21 is useful as a self-mating fastener, the ribs 26 generally have a height that is no greater than a height of the rail segments 4. In the embodiment illustrated in FIG. 4, the height Z3 of the ribs 26 is less than the height of the rail segments 4. In some embodiments, the height Z3 of ribs 26 is up to 95, 90, 80, 75, or 70 percent of the height Z1 of the rail segments 4 (shown in FIG. 6B). In some embodiments, the ribs 26 have a maximum height Z3 (above the backing 2) of up to 2.85 millimeter (mm), 1.25 mm, or 1 mm and, in some embodiments, a minimum height of at least 0.08 mm or 0.16 mm. The height Z3 of the ribs 26 can be in a range from 0.2 mm to 0.6 mm, 0.3 mm to 0.5 mm, 0.3 mm to 0.4 mm, or 0.35 mm to 0.55 mm. In some embodiments, each of the ribs 26 has a height to width (Z3 to X2) aspect ratio that is at least 1.5: 1, at least 2: 1, or at least 3: 1. As shown in FIG. 4, notches 29 in a portion of the ribs 26 distal from the backing 2 can be provided by protrusions in the mold surface useful for making the fastener 21, which is described in greater detail, below.

Another embodiment of a fastener of the present disclosure is shown in FIG. 5. Fastener 31 includes a backing 2 having a length (L), a width (W), and a thickness (T). Fastener 31 includes rows 14 of rail segments 4. The features and dimensions of any of the embodiments described above for the rows 14 and rail segments 4 shown in FIG. 4 can be used in combination with the fastener shown in FIG. 5 to provide corresponding embodiments. In the embodiment illustrated in FIG. 6A, fastener 31 includes rows 16 of posts 6 protruding perpendicularly from the backing 2. For a portion of fastener 31, the rows 14 of rail segments 4 and rows 16 of posts 6 alternate. Fastener 31 can have at least 2, 3, 5, or 10 of the rows 14 of rail segments 4 alternating with at least 2, 3, 5, or 10 of the rows 16 of posts 6. Fastener 31 also includes ribs 26 protruding perpendicularly from the backing 2. Ribs 26 have a continuous base portion 23 attached to the backing 2. In fastener 31, there are two ribs 26 that protrude from the backing between two rows 14 of rail segments 4. In other embodiments, one least one rib 26 protrudes from the backing 2 and may be between two rows 14 of rail segments 4, between a row 14 of rail segments 4 and a row 16 of posts 6, or between two rows 16 of posts 6. Fastener 31 can have at least 2, 3, 5, or 10 of the ribs 26 located regularly or irregularly among the rows 14 of rail segments 4 and rows 16 of posts 6. The heights Z3 and widths X2 of the ribs 26 of fastener 31 can be any of those described above in connection with fastener 21 in FIG. 3 A. Notches 29 in a portion of the ribs 26 distal from the backing 2 can be provided by protrusions in the mold surface useful for making the fastener 31, which is described in greater detail, below.

From the term“rows of posts”, it should be understood that each row 16 includes more than one post 6, and the posts 6 are separated from each other on the backing 2. For example, the posts 6 in a row 16 are separated by a distance Y4 in the direction parallel to the length (L) of the fastener 31. In general, the posts have a length that is different from the length of the rail segments. In the embodiments illustrated in FIGS. 6A to 6C, the length Y1 of the base portion 10 of the rail segments 4 is greater than the length Y2 of the post 6, and the number of posts 6 in one of the rows 16 of posts is more than the number of rail segments 4 in one of the rows of rail segments 14. The length Y1 of the base portion 10 of the rail segments 4 can be at least two, three, or four times the length Y2 of the posts 6. The number of posts 6 in one of the rows 16 of posts can be at least 1.5, 2, or 3 times the number of rail segments 4 in one of the rows of rail segments 14. Since the fastener 31 is useful as a self-mating fastener, the posts generally have a height that is no greater than a height of the rail segments. In the embodiments illustrated in FIGS . 6A to 6C, the height Z3 of the posts 6 is less than the height Z1 of the rail segments 4. In some embodiments, the height Z3 of posts 6 is up to 95, 90, 80, 75, or 70 percent of the height Z1 of the rail segments 4.

Posts useful in the fastener made by the process of the present disclosure may have a variety of cross-sectional shapes in a plane parallel to the backing. For example, the cross-sectional shape of the post may be a polygon (e.g., square, rectangle, rhombus, hexagon, pentagon, or dodecagon), which may be a regular polygon or not, or the cross-sectional shape of the post may be curved (e.g., round or elliptical). In some embodiments, the post has a base attached to the backing and a distal tip, and the distal tip has a cross- sectional area that is less than or equal to a cross-sectional area of the base. The post may taper from its base to its distal tip, but this is not a requirement. In some embodiments, the post has a distal cap with a cap width that is greater than the width of the base. The cap can overhang the base on opposing sides or may overhang the base on all sides. Capped posts useful in the fastener of the present disclosure can have a variety of useful shapes including a mushroom (e.g., with a circular or oval head enlarged with respect to the stem), a nail, a T, or a golf tee. Referring again to FIGS. 6A to 6C, in some embodiments, posts 6 useful in the fastener of the present disclosure have a maximum width X2 of up to about 0.5 mm, 0.4 mm, 0.3 mm, or 0.2 mm and a minimum width of at least 0.05 mm, 0.1 mm, or 0.125 mm. Some useful widths X2 of the posts 6 are in a range from 0.05 mm to 0.5 mm, 0.1 mm to 0.2 mm, or 0.125 mm to 0.175 mm. In some embodiments, posts 6 useful in the fastener of the present disclosure have a maximum length Y2 of up to about 0.5 mm, 0.4 mm, 0.3 mm, or 0.2 mm and a minimum width of at least 0.05 mm, 0.1 mm, or 0.125 mm. Some useful widths Y2 of the post 6 are in a range from 0.05 mm to 0.5 mm, 0.1 mm to 0.2 mm, 0.1 mm to 0.15 mm, or 0.125 mm to 0.175 mm. In some embodiments, the distance Y4 between posts 6 in the direction parallel to the length (1) of the fastener 1 is up to about up to about 1.5 mm (in some embodiments, up to 1.25, 1.0, 0.9, or 0.8) mm and at least about 0.1 mm, 0.2 mm, or 0.4 mm. The distance Y4 between posts 6 can be in a range from 0.1 mm to 1.5 mm, 0.2 mm to 1.0 mm, or 0.400 mm to 0.600 mm.

For embodiments such as the embodiment illustrated in FIG. 6C, posts 6 that taper from their bases to their distal tips have a sloping face and a taper angle A2 between the sloping face and the backing 2. In some embodiments, the taper angle A2 between the sloping face of the post 6 and the backing 2 is in a range from 91 degrees to 130 degrees, in some embodiments, in a range from 91 degrees to 125 degrees, 91 degrees to 120 degrees, 91 degrees to 115 degrees, 91 degrees to 110 degrees, 91 degrees to 105 degrees, 95 degrees to 100 degrees, 91 degrees to 105 degrees, 91 degrees to 100 degrees, 91 degrees to 99 degrees, 91 degrees to 97 degrees, or 91 degrees to 95 degrees.

In some embodiments, the posts 6 have a maximum height Z3 (above the backing 2) of up to 2.85 millimeter (mm), 1.25 mm, or 1 mm and, in some embodiments, a minimum height of at least 0.08 mm or 0.16 mm. The height Z3 of the posts can be in a range from 0.2 mm to 0.6 mm, 0.3 mm to 0.6 mm, 0.3 mm to 0.4 mm, or 0.35 mm to 0.55 mm. In some embodiments, each of the posts has a height to width aspect ratio that is at least 1.5 : 1 , at least 2 : 1 , or at least 3: 1. In some embodiments, each of the posts has a height to length aspect ratio that is at least 1.5 : 1 , at least 2 : 1 , or at least 3 : 1.

FIG. 6A illustrates another embodiment of a portion of the fastener 31 that includes the rows or rail segments and rows of posts. In this embodiment, the cap portion 8 of the rail segment 4 has a different shape than the cap portion 8 of the embodiment shown in FIG. 5. A combination of the cap shapes shown in FIGS. 5 and 6A may also be useful.

Fastener 1, 21, 31 is useful, for example, as a self-mating fastener. As used herein, self-mating refers to fasteners in which fastening is accomplished by interengaging fastening elements of the same type (e.g., fastening heads). In some embodiments, self-mating refers to fasteners in which fastening is accomplished by interengaging fastening elements of identical shape. In some embodiments, self-mating refers to the ability for the fastener to engage with itself when it is in a folded configuration, for example, along an axis parallel to either the length (L) or width (W) of the fastener, referring to FIGS. 3 A , 4, or 5. Two fastener members (e.g., first and second fastener members (1,5)), each having the structure shown in FIGS. 3A and 3B, for example, can be fastened together in a self-mating engagement as shown in FIG. 3C. In some embodiments, a first fastener member 1 is a fastener of the present disclosure as described above in any of its embodiments, and a second fastener member may include the rail segments but not include the ribs. In some embodiments, the first and second fastener members may be different embodiments of the fastener of the present disclosure. For example, the first fastener member 1 may have a cap shape for the rail segments like that shown in FIG. 5 and a second fastener member 5 may have a cap shape like that shown in FIG. 6A. In another example, a first fastener member 1 having a configuration shown in FIG. 3A can be used with a second fastener member shown in FIG. 4. Since self-mating includes fasteners having fastening elements of the same type, each of these is an example of self-mating.

In embodiments including rows of rail segments and rows of posts such as those shown in FIGS. 5 and 6A to 6C, when the first and second fastener members undergo fastening, the posts typically bend away from the rail segments while the cap portions of the rail segments of the first and second fastener members pass by each other as shown in FIG. 7A. The posts then return to their original positions after the first and second fastener members are fastened as shown in FIG. 7B.

Accordingly, in some embodiments, the posts have a lower bending stiffness than that of the rail segments. The bending stiffness k for small strain behavior is determined by the equation k=3EI/H, in which E is the modulus of the material making up the posts and the rail segments, H is the height of the posts or rail segments, and I=W ³ L/12, in which W is the width and L is the length of the posts or rail segments. In some embodiments, the length of the base portion of the rail segments is greater than a length of the posts. In these embodiments, when the width of the base portion and the width of the posts are similar, the bending stiffness of the rail segments will be higher than the bending stiffness of the posts. Referring again to FIG. 6A, the rows 14 of rail segments 4 can collectively have a higher bending stiffness than rows 16 of posts 6. When there are more posts 6 in a row 16 of posts, the bending stiffness of the posts can be adjusted (e.g., by selection length or width) so that collectively the row 16 of posts 6 has less bending stiffness than a row 14 of rail segments 4. The bending stiffness of each row of rail segments or posts can be determined by the number of rail segments or posts in each row and the bending stiffness of each of the rail segments or posts.

In some embodiments, the fastening system of the present disclosure is releasably fastenable. As used herein, the term“releasably fastenable” means that the fastener members can alternate between the fastened and unfastened configurations one or more times without destroying the functionality of the fastener. In some embodiments, the unique structure of the fastener of the present disclosure can allow for multiple cycles of fastening and unfastening without excessive plastic (i.e., irreversible) deformation of the engaging rail segments. As described in detail in the Examples, below, a comparative fastener that includes rail segments but no posts can undergo fastening when the rail segments are pushed against and past one another for interlocking. The cap portions of the rail segments of comparative fastener exhibit a relative high degree of plastic (i.e., irreversible) deformation after such engagement as shown in FIG. 8. The plastic deformation can limit the ability of the comparative fastener to be unfastened and refastened since the shape of the fastener is altered by the first and successive engagements. In contrast, in embodiments in which the first and second fastener members include posts, when the first and second fastener members undergo fastening, the posts undergo elastic deformation while the cap portions of the rail segments of the first and second fastener members pass by each other as shown in FIG. 7A. The cap portions of the rail segments of the fastener of the present disclosure exhibit a relative low degree of plastic (i.e., irreversible) deformation after engagement as shown in FIG. 7B.

Since fastener 1, 21, 31 illustrated in FIGS. 3 A to 3 C, 4, 5, and 6A to 6C is useful, for example, as a self-mating fastener, a shortest distance X8 between one of the ribs 26 or posts 6 and one of the base portions 10 of adjacent rail segments 4 or rails 24 is wide enough to allow the insertion of the cap or engaging portion 8, 28 of the rail segments 4 or rails 24. In FIG. 6B, distances X3, X5, and X8 can represent the distance between a rail segment 4 and a post 6, a rail segment 4 and a rib 26, or a rail 24 and a rib 26. Distance X8 may be substantially the same as X4, as described above in any of the embodiment for X4. In some embodiments, distance X8 is within about 20, 15, or 10 percent of the cap width X4. In some embodiments, a ratio of the distance X8 to the width XI of the base portion 10 is in a range from 2: 1 to 5: 1 or from 2 : 1 to 4 : 1 , or the ratio may be about 3: 1. Distances X3 and X5 between one of the ribs 26 or posts 6 and one of the cap or engaging portions 8, 28 of adjacent rail segments 4 or rails 24 is generally smaller than distance X8 since the cap width X4 is wider than the width of the base portion XL Some useful distances X3 and X5 are in a range from 0.08 mm to 0.8 mm, 0.1 mm to 0.5 mm, 0.2 mm to 0.4 mm, or 0.2 mm to 0.35 mm. Distances X3 and X5 between a post 6 or rib 26 and two adjacent cap or engaging portions 8, 28 need not be equal.

In some embodiments, when the first and second fastener members are fastened, they can slide relative to each other in a direction parallel to the length of the backing. This may be advantageous, for example, if the positioning of the first and second fastener members relative to each is not desirable when the first and second fastener members are initially fastened. To achieve a desirable positioning the first and second fastener members can be slid into place.

The first and second fastener members of a fastening system made by the process of the present disclosure may or may not be connected together. In some embodiments, the first and second fastener members may be connected to two discrete substrates. In some embodiments, the first and second fastener members may be part of the same strip of material in which the first fastener member is folded over to contact the second fastener member.

In the structured film made by the process of the present disclosure, the rail segments, ribs, at least a portion of the backing, and, in some embodiments, posts, are integral (that is, generally formed at the same time as a unit, unitary). Fastening elements such as rail segments, ribs, and upstanding posts on a backing can be made, for example, by feeding a thermoplastic material onto a continuously moving mold surface with cavities having the inverse shape of the fastening elements. The thermoplastic material can be passed between a nip formed by two rolls or a nip between a die face and roll surface, with at least one of the rolls having the cavities. Pressure provided by the nip forces the resin into the cavities. In some embodiments, a vacuum can be used to evacuate the cavities for easier fdling of the cavities. The nip has a large enough gap such that a coherent backing is formed over the cavities. The backing may be formed with no holes therethrough. The mold surface and cavities can optionally be air or water cooled before stripping the integrally formed backing and fastening elements from the mold surface such as by a stripper roll.

Suitable mold surfaces for forming fastening elements on a backing include tool rolls such as those formed from a series of plates defining a plurality of cavities about its periphery including those described, for example, in U.S. Pat. No. 4,775,310 (Fischer). Cavities may be formed in the plates by drilling or photoresist technology, for example. Other suitable tool rolls may include wire-wrapped rolls, which are disclosed along with their method of manufacturing, for example, in U.S. Pat. No. 6,190,594 (Gorman et ah). Another example of a method for forming a backing with upstanding fastening elements includes using a flexible mold belt defining an array of fastening element-shaped cavities as described in U.S. Pat. No. 7,214,334 (Jens et ak). Yet other useful methods for forming a backing with upstanding fastening elements can be found in U.S. Pat. Nos. 6,287,665 (Hammer), 7, 198,743 (Tuma), and 6,627,133 (Tuma).

FIG. 1 illustrates one process in which a tool roll 610 can be used to form a fastener having at least one of protruding rail segments, posts, ribs, and/or rails. A thermoplastic material 660 can be applied to the surface of the tool roll 610 from source 662 by extrusion or cast molding, for example, to create a film 670 including fastening elements 672 on a backing 674 that are replicas of the mold cavities in the tool roll 610. Tool roll 610 and second roll 680 form a nip.

FIG. 2 is an enlarged cut-away perspective view of a portion of a surface of a tool roll useful in a process for making a fastener useful in the reclosable package of the present disclosure. Tool roll 810 is useful for making continuous ribs and rails for some embodiments of fasteners useful for practicing the present disclosure. Tool roll 810 includes grooves 820a, 820b formed between higher-profile areas 840. For making ribs 26 and rails 24 shown in FIGS. 11 to 13, grooves 820a, 820b have generally a rectangular profile although different shapes can be used to provide a film with differently shaped ribs and rails. Grooves 820a, 820b have different depths so that ribs of different heights can be formed on a backing. Taller ribs may be preferentially capped using the methods described below.

Grooves 820a, 820b and higher-profile areas 840 can be formed in tool roll 810 using a variety of techniques. For example, grooves 820a, 820b and higher-profile areas 840 can be formed from a series of plates having different diameters that are stacked together to collectively form a tool roll or rings having different diameters that are stacked together and placed over a cylindrical base roll. Useful materials for making rings include stainless steel SS430, cold rolled steel, and copper. The cylindrical base roll or mandrel can be made out of aluminum wall, steel wall, or stainless steel wall and can be a water pressure vessel through which water can be passed for cooling and heating. Tool roll 810 may also be a wire-wrapped roll, with wires helically wound around a base roll. Wire forming higher-profde area 840 has a higher profde than another wire, resulting in a tool roll 810 on which grooves 820 are formed between windings of the higher profde wire. Grooves 820 can also be machined into the surface of a metal master roll made, for example, of eletroformed nickel or into screens formed into sleeves to fit over a cylindrical base roll.

Grooves 820 are provided with multiple protrusions 830. We have unexpectedly found that grooves that are up to 250 micrometers, in some embodiments, less than 250, up to 130, up to 110, up to 100, or up to 80 micrometers, in width and at least 250 micrometers, in some embodiments, at least 350, 400, 450, or 500 micrometers, in depth do not fill with moldable material when using a relatively low- pressure nip (e.g., less than 150 pounds per lineal inch (571 N/mm)). Instead, we found that only about 25 percent or 50 percent of the depth of the groove was filled even when increasing the pressure. We have further unexpectedly found when the grooves 820a and 820b are formed with multiple protrusion 830 around their peripheral surfaces, the grooves completely fill with moldable material, providing rails in the resulting film of the desired height and including notches 29 as shown in FIGS. 11, 12, and 13. Protrusions can have heights of up to about 50, 40, 30, 20, or 10 percent of the depth of the groove and may be regularly or irregularly spaced. In some embodiments, protrusions are provided every 0.5 mm to 12.5 mm or every 1 mm to 2 mm around the peripheral surface of the groove.

We have found that the presence of ribs, which, in some embodiments, may be capped to form rails, having at least continuous base portions can improve the air sealing of the reclosable package of the present disclosure. Consumers may expect that a reclosable package should remain closed after the fastener is put into a closed configuration and also that the fastener should provide resistance to air flow across the fastener to maintain freshness of the consumer goods inside. If a consumer puts the fastener in a closed configuration is still able to squeeze the air out of the package or smell odor from the package, they may question the effectiveness of the fastener and recloseable package. Inclusion of ribs, which may optionally be capped to form rails, in the fastener useful for practicing the present disclosure improves the air sealing of the reclosable package when evaluated using the test method described in the Examples below. For example, in a comparison of Example 1 and Illustrative Example 3, replacement of a row of posts with a rib having at least a continuous base portion results in more than doubling the air pressure inside the bag introduced using a continuous stream of air.

Air sealing of the reclosable package may further be improved by the presence of adhesive (e.g., pressure sensitive adhesive) on at least a portion of the first major surface of the fastener members. In some embodiments, at least one of the first fastener member or the second fastener member comprises adhesive (e.g., pressure sensitive adhesive) on at least a portion of its first major surface. Pressure sensitive adhesives (PSAs) are well known to those of ordinary skill in the art to possess properties including the following: (1) aggressive and permanent tack, (2) adherence with no more than finger pressure, (3) sufficient ability to hold onto an adherend, and (4) sufficient cohesive strength to be cleanly removable from the adherend. Materials that have been found to function well as PSAs are polymers designed and formulated to exhibit the requisite viscoelastic properties resulting in a desired balance of tack, peel adhesion, and shear holding power.

One method useful for identifying pressure sensitive adhesives is the Dahlquist criterion. This criterion defines a pressure sensitive adhesive as an adhesive having a 1 second creep compliance of greater than 1 x 10 ⁶ cm ² /dyne as described in Handbook of Pressure Sensitive Adhesive Technology, Donatas Satas (Ed.), 2nd Edition, p. 172, Van Nostrand Reinhold, New York, NY, 1989. Alternatively, since modulus is, to a first approximation, the inverse of creep compliance, pressure sensitive adhesives may be defined as adhesives having a storage modulus of less than about 1 x 10 ⁶ dynes/cm ² .

A variety of PSAs may be useful on the first major surface of at least one of the first or second fastener member in the fastening system of the present disclosure. Examples of suitable PSAs include natural rubber-, acrylic-, block copolymer-, silicone-, polyisobutylene-, polyvinyl ether-, polybutadiene-, or and urea-based pressure sensitive adhesive and combinations thereof. These PSAs can be prepared, for example, as described in Adhesion and Adhesives Technology, Alphonsus V. Pocius, Hanser/Gardner Publications, Inc., Cincinnati, Ohio, 1997, pages 216 to 223, Handbook of Pressure Sensitive Adhesive Technology, Donatas Satas (Ed.), 2nd Edition, Van Nostrand Reinhold, New York, NY, 1989, Chapter 15, and U.S. Pat. No. Re 24,906 (Ulrich). PSAs can be strip coated onto the first major surface of at least one of the first or second fastener member using conventional techniques. In some embodiments, areas adjacent ribs rows of posts may be coated with PSA to engage with the cap of rails segments or rails when the self-mating fastener is in the closed configuration.

If rail segments formed upon exiting the cavities do not have caps, first and second fastener members will not have any closure affinity for each other. Caps can be subsequently formed on the rail segments and optionally ribs (to form rails) by a capping method as described in U.S. Pat. No. 5,077,870 (Melbye et ak). Typically, the capping method includes deforming the tip portions of the rail segments using heat and/or pressure. The heat and pressure, if both are used, could be applied sequentially or simultaneously. The formation of rail segments and rails can also include a step in which the shape of the cap is changed, for example, as described in U.S. Pat. No. 6, 132,660 (Kampfer) and/or 6,592,800 (Levitt). For example, one or more of these processes can be useful for changing the shape of the cap portion 8 shown in FIG. 6B to the shape shown in FIG. A. The formation of rail segments and rails can also include a step in which the cap is embossed, for example, as described in U.S. Pat. No. 6,000,106 (Kampfer). After one or more of these capping processes, first and second fastener members in a fastening system of the present disclosure can be closed together. The amount of force necessary to close and to peel open the first and second fastener members can be adjusted as desired by tailoring the capping process.

Another method for making a structured film is profile extrusion described, for example, in U.S. Pat. No. 4,894,060 (Nestegard). Typically, in this method a thermoplastic flow stream is passed through a patterned die lip (e.g., cut by electron discharge machining) to form a web having downweb ridges. Slicing at least some of the ridges and stretching the web can be used to form separated fastening elements. The ridges may be in the final form desired for the ribs and rails described above or may be considered precursors to the rail segments and posts and exhibit the cross-sectional shape of the rail segments and posts to be formed. The ridges can be transversely sliced at spaced locations along the extension of the ridges to form discrete portions of the ridges having lengths in the direction of the ridges essentially corresponding to the length of the fastening elements to be formed. Stretching the backing so that it plastically deforms results in the separation of the rail segments and posts. Notches 29 shown in FIGS. 4A, 5, and 6A would not be formed in ribs made by profile extrusion without a post-extrusion step of removing material from the ribs.

The process of the present disclosure may utilize a variety of suitable materials, including thermoplastics. Examples of thermoplastic materials suitable for making the fastener using the methods described above include polyolefin homopolymers such as polyethylene and polypropylene, copolymers of ethylene, propylene and/or butylene; copolymers containing ethylene such as ethylene vinyl acetate and ethylene acrylic acid; polyesters such as poly(ethylene terephthalate), polyethylene butyrate, and polyethylene napthalate; polyamides such as poly(hexamethylene adipamide); polyurethanes; polycarbonates; poly(vinyl alcohol); ketones such as polyetheretherketone; polyphenylene sulfide; and mixtures thereof. In some embodiments, the thermoplastic useful for making the fastener comprises at least one of a polyolefin, a polyamide, or a polyester. In some embodiments, the thermoplastic useful for making the fastener is a polyolefin (e.g., polyethylene, polypropylene, polybutylene, ethylene copolymers, propylene copolymers, butylene copolymers, and copolymers and blends of these materials). In some embodiments, the fastener of the present disclosure is made from a blend of any of these thermoplastic materials and an elastomer. Examples of elastomers useful in such tie layers include elastomers such as ABA block copolymers (e.g., in which the A blocks are polystyrenic and formed predominantly of substituted (e.g., alkylated) or unsubstituted moieties and the B blocks are formed predominately from conjugated dienes (e.g., isoprene and 1,3-butadiene), which may be hydrogenated), polyurethane elastomers, polyolefin elastomers (e.g., metallocene polyolefin elastomers), olefin block copolymers, polyamide elastomers, ethylene vinyl acetate elastomers, and polyester elastomers. Examples of useful polyolefin elastomers include an ethylene propylene elastomer, an ethylene octene elastomer, an ethylene propylene diene elastomer, an ethylene propylene octene elastomer, polybutadiene, a butadiene copolymer, polybutene, or a combination thereof. Elastomers are available from a variety of commercial sources as described below. Any of these elastomers may be present in a blend with any of the thermoplastics in an amount of up to 20, 15, or 10 percent by weight.

The backing of the fastener made by the process of the present disclosure may have a variety of thicknesses. In some embodiments, including the embodiments illustrated in FIGS. 3A to 3C, 4, 5, and 6A to 6C, the thickness (Z4-Z5) of the backing 2 integral with the rails 24, ribs, 26, rail segments 4, and posts 6 may be up to about 300 micrometers (pm), 250 micrometers, or 200 micrometers and at least about 50 micrometers or 75 micrometers. This thickness does not include the heights of the fastening elements protruding from the first major surface of the backing. In some embodiments, the thickness of the thermoplastic backing is in a range from 50 to about 300 micrometers, from about 50 to about 200 micrometers, or from about 50 to about 150 micrometers.

In some embodiments, including the embodiments illustrated in FIGS. 4, 5 and 6A to 6C, the rows of rail segments 14 and rows of posts 16 are each independently formed on fillets 12. Referring to FIG. 6C, the fillet thickness Z6 above the backing 2 may be up to about 100 micrometers (pm), 75 micrometers, or 50 micrometers and at least about 10 micrometers or 15 micrometers. This thickness does not include the heights of the rail segments and posts protruding from the first major surface of the backing. In some embodiments, the fillet thickness Z6 is in a range from 10 to about 100 micrometers, from about 15 to about 75 micrometers, or from about 20 to about 50 micrometers. In some embodiments, the backing, excluding the rail segments, ribs, and optionally posts and fillets, is substantially uniform in thickness. For a thermoplastic that is substantially uniform in thickness, a difference in thickness between any two points in the backing may be up 5, 2.5, or 1 percent.

Rail segments on the first surface of the backing may have a density of at least 10 per square centimeter (cm ² ) (63 per square inch in ² ). For example, the density of the rail segments may be at least 100/cm ² (635/in ² ), 248/cm ² (1600/in ² ), 394/cm ² (2500/in ² ), or 550/cm ² (3500/in ² ). In some embodiments, the density of the rail segments may be up to 1575/cm ² (10000/in ² ), up to about 1182/cm ² (7500/in ² ), or up to about 787/cm ² (5000/in ² ). Densities in a range from 10/cm ² (63/in ² ) to 1575/cm ² (10000/in ² ) or 100/cm ² (635/in ² ) to 1182/cm ² (7500/in ² ) may be useful, for example. The density of the rail segments is related to the distance between rail segments X7, measured as the center-to-center distance of the rail segments in adjacent rows as shown in FIG. 6C. A variety of distances X7 between rows of rail segments can be useful. In some embodiments, the distance X7 between rows of rail segments is 0.25 mm to 2.5 mm, 0.5 mm to 1.5 mm, or 0.6 mm to 1.2 mm. The spacing of the rows of rail segments and the posts need not be uniform, for example, as shown in FIGS. 12 to 14.

In some embodiments, the backing can be monoaxially or biaxially stretched. Stretching in the machine direction can be carried out on a continuous web of the backing, for example, by directing the web over rolls of increasing speed. Stretching in a cross-machine direction can be carried out on a continuous web using, for example, diverging rails or diverging disks. A versatile stretching method that allows for monoaxial and sequential biaxial stretching of the thermoplastic layer employs a flat film tenter apparatus. Such an apparatus grasps the thermoplastic layer using a plurality of clips, grippers, or other film edge- grasping means along opposing edges of the thermoplastic web in such a way that monoaxial and biaxial stretching in the desired direction is obtained by propelling the grasping means at varying speeds along divergent rails. Increasing clip speed in the machine direction generally results in machine-direction stretching. Stretching at angles to the machine direction and cross-direction are also possible with a flat film tenter apparatus. Monoaxial and biaxial stretching can also be accomplished, for example, by the methods and apparatus disclosed in U.S. Pat. No. 7,897,078 (Petersen et al.) and the references cited therein. Flat fdm tenter stretching apparatuses are commercially available, for example, from Bruckner Maschinenbau GmbH, Siegsdorf, Germany.

In some embodiments, after stretching, the backing has an average thickness of up to 150 pm, 125 pm, 100 pm, 80 pm, or 75 pm. In some embodiments, the average thickness of the backing after stretching is in a range from 30 pm to 150 pm, 50 pm to 150 pm, or 50 pm to 125 pm. In general, the backing has no through-holes before or after stretching. In some embodiments, the density of the rail segments and/or posts after stretching may be up to about 1182/cm ² (7500/in ² ) or up to about 787/cm ² (5000/in ² ). Densities after stretching in a range from 2/cm ² (13/in ² ) to 1182/cm ² (7500/in ² ), 124/cm ² (800/in ² ) to 787/cm ² (5000/in ² ), 248/cm ² (1600/in ² ) to 550/cm ² (3500/in ² ), or 248/cm ² (1600/in ² ) to 394/cm ² (2500/in ² ) may be useful, for example. Again, the spacing of the spacing of the rows of rail segments and the posts need not be uniform.

In some embodiments, the backing is not stretched and does not have stretch-induced molecular orientation that is typically detected by standard spectrographic analysis of the birefringent properties of the backing.

In some embodiments, the backing includes a multi-layer construction. The multi-layer construction can include from 2 to 10, 2 to 5, or 2 to 3 layers. The multiple layers can include films, adhesives, and tie layers. The multiple layers can be joined together using a variety of methods including coating, adhesive bonding, and extrusion lamination. In some embodiments, the backing having the protruding rail segments and posts can be made (e.g., using any of the methods described above) from a multilayer melt stream of thermoplastic materials. This can result in the protruding rail segments and ribs formed at least partially from a different thermoplastic material than the one predominately forming the backing. Various configurations of upstanding posts made from a multilayer melt stream are shown in U. S. Pat. No. 6,106,922 (Cejka et ah), for example. In some embodiments, the thickness of the backing (including a multi-layer backing) combined with the height of the rail segments is up to 3300, 2000, 1000, 900, 800, 700, 650, 600, 500, 540, or 400 micrometers. In some embodiments, the thickness of the fastening system according to the present disclosure, in which the first and second fastener members are engaged with each other is up to 3300, 2000, 1000, 900, 800, 750, or 700 micrometers.

The bending stiffness of the fastener (e.g., at an axis parallel to the width of the fastener) is influenced by the modulus of the material or materials making up the backing, the thickness of the layer or layers making up the backing, the distance between the structures (including rail segments and posts) on the backing, and the dimension of the fastener in a parallel to the bending axis. In general, materials, thicknesses of the layer or layers in the fastener, and distances between structures can be selected to provide the fastener with a desirable bending stiffness. Advantageously, in many embodiments of the fastener of the present disclosure, the bending stiffness of the fastener is low enough such that the fastener does not unintentionally open when the fastener is bent. In some of these embodiments, the bending stiffness of the fastener in a closed configuration is in a range from 100 mN/mm to 1500 mN/mm, 200 mN/mm to 1200 mN/mm, or 300 mN/mm to 1000 mN/mm as measured by a Flexural Stiffness Test Method, for example, as described in the Examples, below.

In some embodiments, the fastener of the present disclosure and/or the backing of the fastener includes a tie layer. Tie layers can include elastomeric materials or other materials that have lower melting points than the backing integral with the rail segments and posts. Examples of elastomers useful in such tie layers include elastomers such as ABA block copolymers (e.g., in which the A blocks are polystyrenic and formed predominantly of substituted (e.g., alkylated) or unsubstituted moieties and the B blocks are formed predominately from conjugated dienes (e.g., isoprene and 1,3-butadiene), which may be hydrogenated), polyurethane elastomers, polyolefin elastomers (e.g., metallocene polyolefin elastomers), olefin block copolymers, polyamide elastomers, ethylene vinyl acetate elastomers, and polyester elastomers. Examples of useful polyolefin elastomers include an ethylene propylene elastomer, an ethylene octene elastomer, an ethylene propylene diene elastomer, an ethylene propylene octene elastomer, polybutadiene, a butadiene copolymer, polybutene, or a combination thereof. Various elastomeric polymers and other polymers may be blended to have varying degrees of elastomeric properties. For example, any of these elastomeric materials may be present in a range from 50% by weight to 95% by weight in a blend with any of the thermoplastics described above for forming the backing integral with the rail segments and posts.

Many types of elastomers are commercially available, including those from BASF, Florham Park, N.J., under the trade designation "STYROFLEX", from Kraton Polymers, Houston, Tex., under the trade designation "KRATON", from Dow Chemical, Midland, Mich., under the trade designation "PELLETHANE", “INFUSE”, VERSIFY”, “NORDEL”, and “ENGAGE”, from DSM, Heerlen, Netherlands, under the trade designation "ARNITEL", from E. I. duPont de Nemours and Company, Wilmington, Del., under the trade designation "HYTREL", from ExxonMobil, Irving, Tex. under the trade designation“VISTAMAXX”, and more.

In some embodiments, the fastener of the present disclosure and/or the backing of the fastener includes a layer of a hot melt adhesive. Hot melt adhesives are typically non-tacky at room temperature, and use of hot melts can decrease contamination on equipment during the handling of the film and lamination. Suitable hot melt adhesives include those based on ethylene -vinyl acetate copolymers, ethylene-acrylate copolymers, polyolefins, polyamides, polyesters, polyurethanes, styrene block copolymers, polycaprolactone, and polycarbonates and may include a variety of tackifying resins, plasticizers, pigments, fillers, and stabilizers. Examples of suitable hot melt adhesives include those available from 3M Company, St. Paul, Minn., under the trade designation“3M SCOTCH-WELD” hot melt adhesives (e.g., products 3731 B and 3764 PG).

In some embodiments, the tie layer or hot melt adhesive will be thermally activated in a temperature range of 90 ^° C to 125 ^° C depending on time and pressure and can be useful for making a secure bond to a substrate, such as a film used in a reclosable package. Referring again to FIG. 6C, the tie layer or hot melt adhesive layer 3 can have any useful thickness Z5. In some embodiments, the tie layer or hot melt adhesive layer 3 has a thickness Z5 of up to 0.1 mm, 0.075 mm, 0.05 mm, or 0.025 mm. Typically, the tie layer or hot melt adhesive layer 3 has a thickness of at least 0.005 mm or 0.01 mm. Useful thicknesses Z5 include those in a range from 0.005 mm to 0.1 mm, 0.005 mm to 0.05 mm, and 0.01 mm to 0.025 mm.

The fastener made by the process of the present disclosure can be useful for joining two articles together for a variety of purposes. For example, the fastener of the present disclosure can be useful as a self-mating fastener for a reclosable package. The self-mating fastener can be connected to a package or pouch. The self-mating fastener can include an open configuration and a closed configuration. When in the open configuration, the self-mating fastener is adapted to allow access to an interior volume of the pouch through an opening disposed in the pouch after a first opening of the pouch. Further, when in the closed configuration, the self-mating fastener is adapted to prevent access to the interior volume of the pouch through the opening.

FIGS. 9 to 14 are various views of one embodiment of a reclosable package 100. The reclosable package 100 includes a pouch 120 that defines an interior volume 122 and an opening 124 that provides access to the interior volume. The pouch 120 also includes an upper seal region 140 disposed adjacent the opening 124 that is adapted to be broken to allow a first opening of the pouch. The reclosable package 100 also includes a self-mating fastener 150 connected to the pouch 120. The self-mating fastener 150 can include any suitable fastener, e.g., fastener 1, 21, 31 of FIGS. 4A to 4C, 5, and 6A to 6D. The self-mating fastener 150 includes an open configuration (as shown in FIG. 11) and a closed configuration (as shown in FIGS. 9 and 10). When in the open configuration, the self-mating fastener 150 is adapted to allow access to the interior volume 122 of the pouch 120 through the opening 124 after the seal region 140 has been broken. Further, when in the closed configuration, the self-mating fastener 150 is adapted to prevent access to the interior volume 122 of the pouch 120 through the opening 124.

As used herein, the term“allow access” means that a user of the reclosable package 100 can reach into the interior volume 122 of the pouch 120 through the opening 124 and grasp at least a portion of consumer goods disposed within the interior volume. Further, as used herein, the term“prevent access” means that the user of the reclosable package cannot reach into the interior volume 122 of the pouch 120 through the opening 124 to grasp at least a portion of the consumer goods disposed within the interior volume without first manipulating the self-mating fastener 150.

The pouch 120 can include any suitable bag or package that defines the interior volume 122. Further, the pouch 120 can be adapted to contain any suitable items. In some embodiments, the pouch 120 can be adapted to contain any suitable consumer goods, e.g., foodstuffs such as crackers, potato chips, and cheese, bulk granular or powdered products, animal feed, lawn and garden products, etc.

The pouch 120 can be formed using any suitable technique or techniques. In the embodiments illustrated in FIGS. 9 to 14, the pouch 120 is formed from a single piece of material or film that is connected along a rear seal region 138 that extends in a vertical direction that is substantially parallel to first and second side edges 134, 136 of the pouch as shown in FIG. 10. Further, the pouch 120 includes the upper seal region 140 and a lower seal region 142. The rear, upper, and lower seal regions 138, 140, 142 can be formed using any suitable technique or techniques, e.g., ultrasonic welding, adhering (e.g., using a hot melt adhesive as described herein), heat sealing, and combinations thereof. In some embodiments, the seal regions 138, 140, 142 can be formed using the same technique or techniques. In some embodiments, one or more of the seal regions 138, 140, 142 can be formed using a technique that is different from the technique utilized to form the other seal regions.

The pouch 120 can have any suitable dimensions and take any suitable shape or combination of shapes. Further, the pouch 120 includes a front panel 130 and a back panel 132. The front panel 130 and the back panel 132 can meet at the first and second side edges 134, 136. In some embodiments, the front panel 130 and the back panel 132 are integral such that the pouch 120 does not include seams or seal regions adjacent one or both of the first and second side edges 134, 136. As used herein, the term“adjacent the side edge” means that an element or component of the package 100 is disposed closer to one of the first and second side edges 134, 136 than to the rear seal region 138. In some embodiments, the front and back panels 130, 132 can be connected to each other at side edges 134, 136 using any suitable technique or techniques. For example, in some embodiments, the front panel 130 and the back panel 132 can be made separately and then joined together at the first and second side edges 134, 136 by connecting the front panel to the back panel.

The pouch 120 can include the opening 124 (FIG. 11) that provides access to the interior volume 122. The opening 124 can be disposed in any suitable location on the pouch 120. As shown in FIG. 11, the opening 124 is disposed adjacent a top edge 126 of the pouch 120. As used herein, the term“adjacent the top edge” means that an element or component of the package 100 is disposed closer to the top edge 126 of the pouch 120 than to a bottom edge 128 of the pouch. The opening 124 can take any suitable shape and have any suitable dimensions. In some embodiments, the opening extends between first and second side edges 134, 136 of the pouch. In some embodiments, one or more seal regions may be disposed between edges of the opening 124 and the first and second side edges 134, 136 of the pouch 120 such the opening does not extend to one or both of the first and second side edges of the pouch. In some embodiments, the opening 124 of the pouch 120 can be defined by the top edge 126 of the pouch.

In some embodiments, the pouch 120 can include a seal region disposed adjacent the opening 124 that is adapted to be broken to allow a first opening of the pouch such that the user can access consumer goods disposed within the interior volume 122. As used herein, the term“first opening” refers to the first time that the reclosable package is opened by the user following manufacturing and filling of the package. In the embodiments illustrated in FIGS. 9 to 14, such seal region includes the upper seal region 140. The upper seal region 140 seals the pouch 120 prior to the first opening of the pouch to preserve the consumer goods disposed within the interior volume 122. To access such consumer goods, the user can break the upper seal region 140 using any suitable technique or techniques, e.g., pulling apart, tearing, cutting, etc.

The pouch 120 can be made using any suitable material or materials, e.g., one or more inorganic, polymeric, and metallic materials. In some embodiments, the pouch 120 can include one or more polymeric materials such as a polyolefin (e.g., oriented polypropylene OPP, low density polyethylene (LDPE), and linear low polyethylene (LLDPE)), a polyester (e.g., polyethylene terephthalate) (PET)), a polyacrylate, and ethylene vinyl alcohol (EVOH). Films of these materials are available as single-layer films, for example, and as multiple layer films including functional tie layers. Multiple layer films can be made by coextrusion or stepwise extrusion. The functional tie layer can be made of any of the polymeric materials described for the pouch blended with 5% by weight to 50% by weight of a functional polymer. The multiple layer film is usually configured with the tie layer on the inside of the pouch 120 and can allow for adhesive bonding and hermetic sealing of the pouch. Many functional polymers useful as tie layer resins are commercially available, for example, from Dow Chemical Company under the trade designation “AMPLIFY”. In some embodiments, the pouch 120 can include a flexible material. Tie layers on the pouch may also include any of the elastomeric materials described above in connection with the tie layer on the fastener.

The pouch 120 can include any suitable graphic or graphics (not shown) disposed on one or both of the front and back panels 130, 132 using any suitable technique or techniques, e.g., ink jet printing, laminating, digital printing, flexographic printing, screen printing, ink transfer, and combinations of these. In some embodiments, the graphic (not shown) can be disposed on the front panel of the pouch, where a portion of the graphic is disposed over the self-mating fastener 150 when the fastener is in the closed configuration.

Connected to the pouch 120 is the self-mating fastener 150 of the present disclosure as described above in any of its embodiments. The self-mating fastener 150 can be connected to the pouch 120 in any suitable location. In the embodiment illustrated in FIGS. 9 to 14, the self-mating fastener 150 is connected to the pouch 120 adjacent the top edge 126 of the pouch. In some embodiments, the self-mating fastener 150 is disposed at the top edge 126 of the pouch 120. Further, in some embodiments, the self-mating fastener 150 can be disposed adjacent a center region 146 of the pouch 120. As used herein, the term “adjacent the center region” means that the self-mating fastener 150 is disposed closer to the center region 146 of the pouch 120 than to the top edge 126 or the bottom edge 128 of the pouch.

Further, the self-mating fastener 150 of the present disclosure can be disposed in any suitable location relative to the opening 124 of the pouch 120 such that the fastener when in the open configuration can allow access to the interior volume 122 of the pouch through the opening, after the upper seal region 140 has been broken and that when in the closed configuration the fastener is adapted to prevent access to the interior volume of the pouch through the opening. For example, as shown in FIG. 11, the self-mating fastener 150 is disposed adjacent the opening 124. As used herein, the term“adjacent the opening” means that the self-mating fastener 150 is disposed such that the fastener can manipulate the opening such that is sufficiently open to allow access to the consumer goods disposed within the pouch 120 and sufficiently closed to prevent access to the consumer goods. In some embodiments, the self-mating fastener 150 can be disposed within the opening 124. In some embodiments, the self-mating fastener 150 can be disposed outside of the opening 124 along an edge of the opening such that the fastener can be manipulated between the open and closed configurations to open and close the opening as is further described herein.

The self-mating fastener 150 can have any suitable dimensions and take any suitable shape or shapes. In some embodiments, the self-mating fastener 150 can be connected to the pouch 120 adjacent the top edge 126 of the pouch and extend between the first and second side edges 134, 136 of the pouch as shown in FIGS. 9 and 10. The self-mating fastener 150 can extend to one or both of the first and second side edges 134, 136 of the pouch. In some embodiments, the self-mating fastener 150 can be adapted such that one or both of a first side edge 156 and a second side edge 158 of the fastener is spaced apart from the respective first and second side edges 134, 136 of the pouch 120 any suitable distance. In such embodiments, the pouch 120 may also include one or more seal regions disposed between one or both of the first and second side edges 156, 158 of the self-mating fastener 150 and the first and second side edges 134, 136 of the pouch 120 such that the fastener along with the seal regions seal the pouch along a width of the pouch.

As shown in FIG. 12, which is a schematic cross-section view of a portion of the pouch 120 of FIGS. 9 to 11, the self-mating fastener 150 includes a first fastener member 152 and a second fastener member 154. The first fastener member 152 can be the same as the second fastener member 154 or different from the second fastener member. Further, the first and second fastener members 152, 154 can be connected to the pouch 120 in any suitable location. In the embodiment illustrated in FIG. 12, the first fastener member 152 is disposed on an inner surface 131 of the front panel 130 and the second fastener member 154 is disposed on an inner surface 133 of the back panel 132. In some embodiments, the first fastener member 152 can be disposed on the inner surface 131 of the front panel 130 adjacent the top edge 126 of the pouch 120, and the second fastener member 154 can be disposed on the inner surface 133 of the back panel 132 adjacent the top edge of the pouch.

In some embodiments, the first fastener member 152 can overlap with the second fastener member 154 in a direction orthogonal to the front and back panels 130, 132 such that at least a portion of the first fastener member can mate with the second fastener member. In some embodiments, the first fastener member 152 is registered with the second fastener member 154 in the direction orthogonal to the front and back panels 130, 132 as shown, e.g., in FIG. 12.

The self-mating fastener 150 can be connected to the pouch 120 using any suitable technique or techniques. In some embodiments, the fastener 150 is adhered to the pouch 120 using any suitable adhesive or combination of adhesives, including any of the hot melt adhesives described herein. Further, in some embodiments, self-mating fastener 150 can be ultrasonically bonded to the pouch 120. In some embodiments, the fastener 150 can be mechanically attached to the pouch 120 using any suitable technique or techniques. In some embodiments, a tie layer as described herein in any of its embodiments may be disposed between one or both of the first and second fastener members 152, 154 and the front and back panels 130, 132 respectively.

When tie layers or hot melt adhesives are used to connect the self-mating fastener 150 of the present disclosure to the pouch 120, heating the adhesive or tie layer can be carried out using high-temperature impingement fluid as described in U.S. Pat. Nos. 9,096,960 (Biegler et al.), 9,126,224 (Biegler et al.), and 8,956,496 (Biegler et al.). In some embodiments, the high-temperature fluid is a high-temperature gas (e.g., air, dehumidified air, nitrogen, an inert gas, a mixture of any of these, or another gas mixture). In some embodiments, the high-temperature fluid is high-temperature air. The high-temperature fluid can be directed toward the tie layer or hot melt adhesive only, or the high-temperature fluid can be directed toward both the tie layer or hot melt adhesive and the film useful for forming the pouch. In some embodiments, high-temperature air is directed toward the tie layer or hot melt adhesive only before it is bonded to the pouch. In some embodiments, connecting the self-mating fastener 150 to the pouch 120 includes impinging high-temperature fluid, including any of those described above, onto a second surface of a web of the self mating fastener while it is moving, wherein the second surface is the surface opposite the first surface bearing the rail segments and posts. In some of these embodiments, the second surface of the web includes a tie layer. In some embodiments, the second surface of the web includes a hot melt adhesive. Optionally, either sequentially or simultaneously, connecting the self-mating fastener 150 to the pouch 120 includes impinging high-temperature fluid, including any of those described above, onto a surface of a web of a film useful for forming the pouch while the web of the film is moving. Connecting the self-mating fastener 150 to the film can then be carried out by contacting the second surface of the web of the self-mating fastener to the web of the film useful for forming the pouch. A heated bar may also be useful for connecting the self-mating fastener to the pouch. The self-mating fastener, tie layer, and/or hot melt adhesive may be contacted with a heated bar one or multiple times to ensure a good bond to the packaging film. Typically, the heated bar is contacted to the non-adhesive-containing side of the packaging film.

As mentioned herein, the self-mating fastener 150 has an open configuration and a closed configuration. For example, as shown in FIG. 12, the self-mating fastener 150 is in the closed configuration such that the user is prevented from accessing the interior volume 122 of the pouch 120 through the opening 124 of the pouch. Further, as shown in FIG. 12, the upper seal region 140 is intact and has not yet been broken upon a first opening of the pouch 120. As a result, the consumer goods disposed within the interior volume 122 of the pouch 120 can be preserved by the seal region 140.

In general, the self-mating fastener 150 can be connected to the pouch 120 such that the fastener is in this closed configuration when the bag is manufactured. In some embodiments, self-mating fastener 150 can be connected to the pouch 120 during manufacturing such that it is in an open configuration. For example, FIG. 13 is a schematic cross-section view of a portion of the pouch 120 of FIGS. 9 to 11. As shown in FIG. 13, the self-mating fastener 150 is in the open configuration. As used herein, the term“open configuration” means that one or more portions of the self-mating fastener 150 has been separated such that the user may reach into the pouch 120 through the opening 124 and the self-mating fastener to grasp a portion of the consumer goods disposed within the interior volume 122 of the pouch.

As also shown in FIG. 13, the upper seal region 140 is still intact and has not yet been broken upon the first opening of the pouch 120. In embodiments where the self-mating fastener 150 is connected to the pouch 120 such that it is in the open configuration prior to the first opening of the pouch 120, the user may grasp portions of the front and back panels 130, 132 and manipulate the panels in a direction away from each other. During this manipulation by the user, the upper seal region 140 may remain intact while portions of the self-mating fastener 50 may be separated such that it is in the open configuration as shown in FIG. 13. In some embodiments, manipulation by the user upon the first opening of the pouch 120 may instead first separate the upper seal region 140 such that the seal region is at least partially broken prior to manipulation of the self-mating fastener 150 from the closed configuration to the open configuration.

FIG. 14 is a schematic cross-section view of the pouch 120 of FIG. 9 to 11, where the upper seal region 140 has been broken upon the first opening of the pouch and the self-mating fastener 150 is in the open configuration. As shown in FIG. 14, the user may now access the interior volume 122 of the pouch 120 through the opening 124 and through the self-mating fastener 150. The user may then manipulate the self-mating closure 150 from the open configuration to the closed configuration such that the user can no longer access the interior volume 122 of the pouch 120.

FIG. 15 is a schematic cross-section view of an embodiment of the opening 124 of pouch 120 of FIG. 9 to 11, where the self-mating fastener 150 is in the closed configuration. The self-mating fastener 150 includes a first fastener member 152 and a second fastener member 154. In the illustrated embodiment, the first fastener member 152 and the second fastener member 154 are part of the same strip of material, folded over onto itself. The self-mating fastener 150 is folded, for example, along an axis parallel to the width (W) of the fastener, referring to FIG. 4A, so that a row of posts 106 is visible in the cross-section view. In the embodiment illustrated in FIG. 15, the first fastener member 152 is disposed on an inner surface 131 of the front panel 130 and the second fastener member 154 is disposed on an inner surface 133 of the back panel 132 of the pouch. The first fastener member 152 is attached to inner surface 131 of the front panel 130 and the second fastener member 154 is attached to inner surface 133 of the back panel 132 using tie layer 103. Advantageously, the thickness of the self-mating fastener 150 in this folded configuration can be up to 1000, 900, 800, 700, 600, 500, 450, or 400 micrometers. Such a thickness can allow the self-mating fastener 150 to be connected to the pouch 120 is in this folded configuration when the bag is manufactured. Any suitable technique or techniques may be utilized by the user to manipulate the self-mating fastener 150 to the closed configuration. For example, the user may press the self-mating closure 150 together by placing one hand on the front panel 130 and another hand on the back panel 132 and pressing the first fastener member 152 against the second fastener member 154. Further, for example, the user may place the package 100 on a flat surface such that either the first or second panels 130, 132 are in contact with the surface, and then press the first and second fastener members 152, 154 together.

When in the closed configuration as shown in FIG. 12, the self-mating fastener 150 may prevent consumer goods disposed within the interior volume 122 of the pouch 120 from falling or spilling out of the pouch through the opening 124. Further, in some embodiments, the self-mating fastener 150 may seal the pouch 120 in the closed configuration such that the consumer goods disposed within the interior volume 122 remain fresh.

Any suitable technique or techniques can be utilized to determine whether the self-mating fastener 150 is in the closed configuration. For example, in some embodiments, the self-mating faster 150 is considered to be in the closed configuration when a force to open the self-mating fastener is at least about 0.1 Newtons and no greater than 1.0 Newtons as determined from the mean maximum load from the T-Peel Test Method described in the Examples. In some embodiments, the force to open the self-mating fastener is in a range 0.2 N to 0.9 N or 0.3 N to 0.8 N as determined from the mean maximum load from the T-Peel Test Method described in the Examples.

Further, in some embodiments, the force required to achieve a closed configuration from an open configuration, as previously defined, is no more than 3.0 Newtons (N) but at least 0.3 N as determined utilizing the Force to Close Test Method described in the Examples. In some embodiments, the force required to achieve a closed configuration from an open configuration is no more than 0.3 N/mm but at least 0.03 N/mm as determined utilizing the Force to Close Test Method. In some embodiments, the force required to achieve a closed configuration from an open configuration is in a range from 0.45 N to 2.7 N or 0.6 N to 2.4 N as determined utilizing the Force to Close Test Method. In some embodiments, transition from an open configuration to a closed configuration is readily achieved with finger pressure.

The self-mating fastener 150 and the material utilized for the pouch 120 can be selected to provide any desirable stiffness in resistance to bending about a pouch axis 102 that is perpendicular to a length 104 of the self-mating fastener as shown in FIG. 9. Any suitable technique or techniques can be utilized to determine the stiffness in resistance to bending of the pouch 120 and the self-mating fastener 150. The self mating fastener 150 can have a flexural rigidity of at least about 100 mN/mm and up to about 1500 mN/mm as determined utilizing the Flexural Stiffness Test Method described in the Examples. In some embodiments, the bending stiffness of the fastener is in a range from 100 mN/mm to 1500 mN/mm, 200 mN/mm to 1200 mN/mm, or 300 mN/mm to 1000 mN/mm as measured by the Flexural Stiffness Test Method. With a bending stiffness in these ranges, typically and advantageously, the fastener does not unintentionally open when the fastener is bent. The various embodiments of a reclosable package described herein can include any suitable configuration of pouch. For example, FIGS. 16 and 17 are various views of another embodiment of a reclosable package 200. All of the design considerations and possibilities regarding the package 100 of FIGS. 9 to 15 apply equally to the package 200 of FIGS. 16 and 17. The reclosable package 200 includes a pouch 220 that defines an interior volume 222 and an opening 224 that provides access to the interior volume. In the embodiment illustrated in FIGS. 16 and 17, the opening is disposed adjacent a top edge 226 of the pouch 220. The pouch 220 also includes an upper seal region 240 disposed adjacent the opening 224 that is adapted to be broken to allow a first opening of the pouch.

The pouch 220 further includes a front panel 230 and a back panel 232. The pouch 220 can be formed utilizing a single film that can be sealed along a first side seal region 234 and a second side seal region 236. In some embodiments, the pouch 220 also includes the upper seal region 240. Further, an opening 241 can be disposed adjacent the upper seal region 240 such that the pouch 220 can be hung on a display rack.

The package 200 also includes a self-mating fastener 250 according to the present disclosure connected to the pouch 220. The self-mating fastener 250 can be connected to the pouch 220 in any suitable location. In some embodiments, the self-mating fastener 250 is disposed adjacent the opening 224 of the pouch 220.

The pouch 220 can also include a bottom gusset 270 disposed adjacent a bottom edge 228 of the pouch. The bottom gusset 270 can be folded inwardly from the bottom edge 228 of the pouch. The bottom gusset 270 can be formed utilizing any suitable technique or techniques.

Further, FIGS. 18 and 19 are various views of another embodiment of a reclosable package 300. All of the design considerations and possibilities regarding the reclosable package 100 of FIGS. 9 to 15 apply equally to the package 300 of FIGS. 18 and 19. The reclosable package 300 includes a pouch 320 having a front panel 330 and a rear panel 332 that can be joined together at a first side seal region 334 and a second side seal region 336. The front and back panels 330, 332 can also be joined together at an upper seal region 340 adjacent a top edge 326 of the pouch. An opening 341 can be disposed adjacent the top edge 326 such that the package 300 can be hung on a display rack. The reclosable package 300 also includes a self-mating fastener 350 of the present disclosure.

The front panel 330 includes a perforated opening 324 that is adapted to allow a user to separate the perforation and access consumer goods disposed within an inner volume 322 of the pouch 320. In some embodiments, the pouch 320 can also include a tear strip (not shown) disposed over the self-mating fastener 350 that is adapted to allow the user to remove the strip and access the interior volume 322 of the pouch.

The self-mating fastener 350 can be disposed adjacent opening 324 on an outer surface 331 of the front panel 330. In some embodiments, portions of the self-mating fastener 350 can extend over the opening . For example, a first fastener member 352 of the self-mating fastener 350 can cover the opening 324 while a second fastener member 354 of the fastener includes a first portion disposed on a portion of the outer surface 331 of the front panel 330 above the opening when the pouch 320 is positioned in a vertical orientation (i.e., a pouch axis that extends parallel to the first and second side seal regions 334, 336 is substantially parallel to a normal to the Earth’s surface), and a second portion of the second fastener member is disposed below the opening. A recess 302 can be formed in the self-mating fastener 350 to allow a user to grasp the first fastener member 352 and pull the first fastener member in a direction away from the second fastener member 354 to manipulate the self-mating fastener from a closed configuration to an open configuration.

The various embodiments of reclosable packages described herein can be manufactured using any suitable technique or techniques. For example, FIG. 20 is a schematic perspective view of one embodiment of an apparatus 400 and method for forming the reclosable package 100 of FIGS. 9 to 15. Although described in reference to reclosable package 100 of FIGS. 9 to 15, the apparatus 400 can be utilized to form any suitable reclosable package. A film 402 is provided either in roll or sheet form and conveyed to station 410, where closure material 408 is connected to the film using any suitable technique or techniques. The film can include a top edge 404 and a bottom edge 406. The closure material 408 can be disposed in any suitable location on the film 402, e.g., adjacent the top edge 404.

The closure material 408 can include any suitable closure material. In some embodiments, the closure material 408 includes the first fastener member 152 mated with the second fastener member 154. In some embodiments, the closure material 408 can include either the first fastener member 152 or the second fastener member 154. In some embodiments, the same closure material can be utilized to form both the first fastener member 152 and the second fastener member 154. In such embodiments, the first fastener member 152 can be disposed on a first region of the film 402, and the second fastener member 154 can be disposed on a second region of the film such the first and second fastener members 152, 154 are aligned when the pouch 120 is formed from the film.

At station 411, the film 402 can be slit or cut to form several individual sheets that are utilized to form individual pouches 120. Further, the lower seal region 142 can be formed at the bottom edge 128 of the pouch 120 at station 411 prior to disposal of consumer goods 416 within the interior volume 122 of the pouch at station 412. After the pouch 120 is filled, the upper seal region 140 can be formed at the top edge 126 of the pouch at station 418 such that the consumer goods 416 are sealed within the package 100. Any suitable technique or techniques can be utilized to form the upper and lower seal regions 140, 142.

Another useful method for making the reclosable package shown in FIGS. 9 to 11 is described in co-pending U.S. Pat. App. Serial No. 62/855,307 (Fuepke et al.) (Attorney Docket No. 81811US002), filed May 31, 2019.

While reclosable packages with fasteners have been reported, the fasteners can be stiff and bulky, making these packages difficult to manufacture and fill with consumer goods. Furthermore, fasteners than utilize hooks and loops can collect particles from the stored consumer goods or the environment outside of the package that contaminate the fastener. Such contamination can prevent the fastener from being completely closed, thereby allowing portions of the consumer goods to spill out of the package or prevent the package from preserving the freshness of the consumer goods.

In addition to the advantages of the fastener made by the process of the present discourse described above, various embodiments of the fastener of the present disclosure can provide one or more advantages over other fasteners currently-available for reclosable packages. For example, some embodiments of the fastener can have a reduced thickness compared to currently-available fasteners such that the fastener can be connected to a packaging fdm used to form the package without compromising roll stability while also minimizing roll loss. As described above, in some embodiments, the thickness of the fastening system according to the present disclosure, in which the first and second fastener members are engaged with each other is up to 1000, 900, 800, 700, 600, 500, 450, or 400 micrometers. Also, as described above, in some embodiments, the fastener includes a tie layer or hot melt adhesive that can be thermally activated at relatively low temperature (e.g., 90 to 125 ^° C). In some embodiments, at least one of the thickness of the fastening system or the low-temperature activation of the tie layer can provide aesthetic advantages when the fastener is attached to a package. For example, any graphics on the package may have little or no distortion in the location of the fastener. Further, the fastener of the present disclosure can be more flexible than currently-available fasteners such that the fastener does not unintentionally open if the fastener is bent, thereby preventing consumer goods disposed within the pouch from spilling out of the pouch. Further, some embodiments of the fastener of the present disclosure can be more contamination-resistant by preventing food debris such as small particles and salt from contaminating the fastener.

Some Embodiments of the Disclosure

In a first embodiment, the present disclosure provides a process for making a structured film, the process comprising:

providing a tool roll comprising a first groove in its outer surface, wherein the first groove has a width of not more than 250 micrometers and a depth of at least 250 micrometers, wherein the first groove is provided with multiple protrusions around its peripheral surface;

contacting the outer surface of the tool roll with a moldable material, wherein the moldable material fills at least 90 percent of the depth of the first groove; and

removing the structured film from the outer surface of the tool roll, wherein the structured film comprises a rib having at least a continuous base portion attached to a first major surface of a backing and a distal portion distal from the backing, wherein the distal portion is provided with and a series of notches corresponding to the multiple protrusions around the peripheral surface of the first groove.

In a second embodiment, the present disclosure provides the process of the first embodiment, wherein the tool roll further comprises a second groove in its outer surface, wherein the second groove has a width of not more than 250 micrometers and a depth of at least 250 micrometers, wherein the depth of the second groove is different from the depth of the first groove, wherein the second groove is provided with multiple protrusions around its peripheral surface, and wherein the structured fdm comprises a second rib having at least a continuous base portion attached to a backing and a distal portion distal from the backing, wherein the distal portion of the second rib is provided with and a series of notches corresponding to the multiple protrusions around the peripheral surface of the second groove.

In a third embodiment, the present disclosure provides the process of the first or second embodiment, wherein the first groove is one of a plurality of first grooves in the outer surface of the tool roll, and wherein the rib is one of a plurality of the ribs protruding from the first major surface of the backing.

In a fourth embodiment, the present disclosure provides the process of the third embodiment, wherein the tool roll comprises a plurality of the first and second grooves alternating along at least a portion of the outer surface of the tool roll, and wherein the structured film comprises a plurality of the first and second ribs alternating along at least a portion of the first major surface of the backing.

In a fifth embodiment, the present disclosure provides the process of any one of the first to fourth embodiments, wherein the width of the first and/or second groove is not more than 125 micrometers.

In a sixth embodiment, the present disclosure provides the process of any one of the first to fifth embodiments, wherein the depth of the first and/or second groove is at least 350 micrometers.

In a seventh embodiment, the present disclosure provides the process of any one of the first to sixth embodiments, wherein a distance between protrusions on the first groove and/or second groove is in a range from 0.5 mm to 12.5 mm.

In an eighth embodiment, the present disclosure provides the process of the seventh embodiment, wherein the rib has an engaging portion distal from the backing, wherein a distance between protrusions on the first groove and/or second groove is in a range from 1 mm to 2 mm.

In a ninth embodiment, the present disclosure provides the process of any one of the first to eighth embodiments, wherein the tool roll further comprises a row of discrete first cavities in its outer surface, each of the discrete first cavities comprising an opening at the outer surface of the tool roll, wherein the moldable material at least partially fills the discrete first cavities, and wherein the structured film comprises first upstanding elements corresponding to the discrete first cavities.

In a tenth embodiment, the present disclosure provides the process of the ninth embodiment, wherein the tool roll further comprises a row of discrete second cavities in its outer surface, each of the discrete second cavities comprising an opening at the outer surface of the tool roll, wherein the discrete first cavities and the discrete second cavities have at least one of different sizes or shapes, wherein the moldable material at least partially fills the discrete second cavities, and wherein the structured film comprises second upstanding elements corresponding to the discrete second cavities.

In an eleventh embodiment, the present disclosure provides the process of the ninth or tenth embodiment, wherein the first upstanding elements comprise a row of rail segments, wherein each of the rail segments has a base portion attached to the backing and a portion distal from the backing, wherein the base portion has a length that is greater than the width of the base portion.

In a twelfth embodiment, the present disclosure provides the process of the eleventh embodiment, wherein a ratio of the length of the base portion to the width of the base portion is at least 2: 1, at least 5: 1, or at least 10: 1.

In a thirteenth embodiment, the present disclosure provides the process of any one of the tenth embodiment or eleventh or twelfth embodiments as they depend on the tenth embodiment, wherein the second upstanding elements comprise a row of posts.

In a fourteenth embodiment, the present disclosure provides the process of the thirteenth embodiment as dependent on the eleventh or twelfth embodiments, wherein a number of posts in one of the rows of posts is more than a number of rail segments in one of the rows of rail segments.

In a fifteenth embodiment, the present disclosure provides the process of the thirteenth or fourteenth embodiment as dependent on the eleventh or twelfth embodiments, wherein the length of the base portion of the rail segments is greater than a length of the posts.

In a sixteenth embodiment, the present disclosure provides the process of any one of the fifteenth embodiment, wherein the length of the base portion of the rail segments is at least two times or three times the length of the posts.

In a seventeenth embodiment, the present disclosure provides the process of any one of the fourteenth embodiment, wherein the number of posts in one of the rows of posts is at least 1.5 or 2 times the number of rail segments in one of the rows of rail segments.

In an eighteenth embodiment, the present disclosure provides the process of any one of the thirteenth to seventeenth embodiments, wherein each of the posts has at least one of a height-to-width aspect ratio that is at least 1.5 : 1 or 2: 1 or a height-to-length aspect ratio that is at least 1.5 : 1 or 2: 1.

In a nineteenth embodiment, the present disclosure provides the process of any one of the thirteenth to eighteenth embodiments, wherein each of the posts has a base attached to the backing and a distal tip, wherein the distal tip has a cross-sectional area that is less than or equal to a cross-sectional area of the base.

In a twentieth embodiment, the present disclosure provides the process of any one of the thirteenth to nineteenth embodiments, wherein the fastener has at least three of the rows of rail segments alternating with at least three of the rows of posts or at least five of the rows of rail segments alternating with at least five of the rows of posts.

In a twenty-first embodiment, the present disclosure provides the process of any one of the eleventh to twentieth embodiments, further comprising deforming each of the rail segments at the portion distal from the backing to form a cap portion distal from the backing, wherein the cap portion has a cap width that is greater than a width of the base portion, and wherein the cap portion overhangs the base portion on opposing sides. In a twenty-second embodiment, the present disclosure provides the process of the twenty-first embodiments, wherein the cap portion overhangs the base portion on all sides.

In a twenty-third embodiment, the present disclosure provides the process of the twenty-first or twenty-second embodiment, wherein the cap portion overhangs the base portion at amount of at least 25 micrometers on the opposing sides.

In a twenty-fourth embodiment, the present disclosure provides the process of any one of the first to twenty-third embodiments, further comprising deforming the rib at the portion distal from the backing to form an engaging portion distal from the backing, wherein the engaging portion has a width that is greater than a width of the continuous base portion, and wherein the engaging portion overhangs the continuous base portion on opposing sides.

In a twenty-fifth embodiment, the present disclosure provides the process of any one of the twenty-first to twenty-fourth embodiments, wherein the deforming is carried out with at least one capping roller

In a twenty-sixth embodiment, the present disclosure provides the process of any one of the first to twenty-fifth embodiments, wherein contacting the outer surface of a tool roll with a moldable material comprises directing the moldable material into a nip formed between the tool roll and a second roll.

In a twenty-seventh embodiment, the present disclosure provides the process of any one of the first to twenty-sixth embodiments, wherein the moldable material is a thermoplastic.

In a twenty-eighth embodiment, the present disclosure provides the process of any one of the first to twenty-seventh embodiments, wherein the tool roll comprises a plurality of rings surrounding a mandrel, wherein a first ring of the plurality of rings has a width of not more than 250 micrometers an outer diameter that is at least 500 micrometers less than others of the plurality of rings, wherein the first ring of the plurality of rings provides the first groove in the outer surface of the tool roll.

In a twenty-ninth embodiment, the present disclosure provides the process of any one of the first to twenty-eighth embodiments, further comprising dispensing adhesive on at least a portion of the first major surface of the backing.

In a thirtieth embodiment, the present disclosure provides the process of the twenty-ninth embodiment, wherein the adhesive is a pressure sensitive adhesive.

In a thirty-first embodiment, the present disclosure provides the process of any one of the first to twenty-eighth embodiments, further comprising coating a tie layer onto a second major surface of the backing opposite first major surface.

In a thirty-second embodiment, the present disclosure provides the process of the thirty-first embodiment, wherein the tie layer comprises a polyolefin elastomer.

In a thirty-third embodiment, the present disclosure provides the process of any one of the first to thirty-second embodiments, wherein the thickness of the backing combined with the height of the first rib is up to 1000 micrometers. In a thirty-fourth embodiment, the present disclosure provides the process of any one of the first to thirty-third embodiments, wherein the backing is formed without through-holes.

In a thirty-fifth embodiment, the present disclosure provides the process of any one of the first to thirty-fourth embodiments, wherein the backing does not have stretch-induced molecular orientation.

In a thirty-sixth embodiment, the present disclosure provides a structured film made by the process of any one of the first to thirty-fifth embodiments.

In a thirty-seventh embodiment, the present disclosure provides a fastening system comprising first and second fastener members, wherein each of the first and second fastener members are made from a structured film of the thirty-sixth embodiment, wherein when the first and second fastener members are fastened, they can slide relative to each other in a direction parallel to the length of the backing.

In a thirty-eighth embodiment, the present disclosure provides a fastening system comprising first and second fastener members, wherein each of the first and second fastener members are made from a structured film of the thirty-sixth embodiment, the fastening system having an improved air seal over a comparative fastening system, wherein the comparative fastening system is the same as the fastening system except having no ribs.

In order that this disclosure can be more fully understood, the following Examples are set forth. It should be understood that these Examples are for illustrative purposes only and are not to be construed as limiting this disclosure in any manner.

EXAMPLES

Dimensions refer to FIG. 6B and 6C, Avg = Average, Each average is of 5 measurements. Data was obtained with a Keyence Digital Microscope, Model VHX-600.

Air Seal Measurement

A 5 -inch by 5 -inch (12.7-cm by 12.7-cm) bag was made where the 5 -inch-long fastener strip was bonded to the packaging film with double sided tape. The width of the fastening strip was 9 mm. The edges of the fastening strip were heat sealed shut to the packaging film to eliminate air escape. Clips were used on the outside of the fastening strip to keep the closure from opening from the compressed air pressure inside the bag and to ensure air flow going through the fastening strip was recorded. Low volume compressed air was introduced into the bottom of the bag which was sealed at the bottom. Higher air pressure means a better air seal for the bag. Three data points were collected for each example and averaged. For Examples 1, 2, and 4 and Illustrative Example 3, a tool roll was created using rings that were laser cut or EDM wire cut with the desired shape and depth of a mold cavity that the molded article would replicate when it is removed from the mold after cooling and solidifying. A combination of spacer rings having 0.015-inch (0.381-mm) thickness and shaped rings having 0.005-inch (0.127-mm) thickness, each made of Stainless Steel 304, were used. The shaped rings included those formed with cavities and/or those with lower diameters and having protrusions. The vertical sides of the shaped rings and spacer rings had a surface roughness suitable for allowing air to escape when filling the mold with molten polymer, typically 100 ra to 150 ra.

For each of Examples 1, 2, and 4 and Illustrative Example 3, a combination of spacer rings and shaped rings selected to provide the desired array in the molded articles were stacked onto an aluminum mandrel and compressed with end loaded caps. The size and shape of the cavities, depressions, and protrusions made from the combination of rings is reflected in the dimensions of the molded articles, reported in the tables, below. The internal ID of the rings was within +/- 0.002 inches (0.05 mm) of the diameter of the mandrel at room temperature. The mandrel was a water pressure vessel that can be heated and cooled with water. To load the rings, the mandrel was cooled at 40 ^° F (4.44 ^° C).

Example 1 : Fastener as shown in FIG. 4

A twin screw 40-mm extruder was used to extrude a blend of 90% by weight food grade Total 3571 homopolymer polypropylene obtained from Total Petrochemicals, Houston, Tex. and 10% by weight “VISTAMAXX 3980FL” Performance Polymer obtained from ExxonMobil, Irving, Tex. A second 1.5- inch (3.8-cm) single screw extruder used to extrude 100%“VISTAMAXX 3980FL” Performance Polymer. Both polymer streams were introduced to an A/B die manifold situated on top of a Cloeren flat sheet die manufactured by Cloeren Inc, Orange Tex). Molten polymer was extruded nominally at 220 ^° C into a rolling cast extrusion takeaway nip with a rubber roll and a tooling roll with the layer including the Total 3571 /“VISTAMAXX 3980FL” Performance Polymer blend against the tooling roll and the layer including 100%“VISTAMAXX 3980FL” Performance Polymer against the rubber roll. The pressure in the nip was 100 pounds per lineal inch (pli) (571 N/mm). The rubber forced the molten polymer blend into the tooling roll having a nominal surface temperature of 50 ^° C to 75 ^° C. The molten polymer solidified on the roll and the structured film was removed from the molding roll after an 180-degree wrap from the rubber roll as described by U.S. Pat. No. 6, 106,922 (Cejka). The layer of 100%“VISTAMAXX 3980FL” contacted the rubber roll and subsequently had a thickness of 10 micrometers. The tool roll had a combination of cavities providing discontinuous rail segments deeper then shorter continuous rail segments. The cavities providing continuous rail segments have protrusions to improve polymer filling of the continuous rails the low nip pressure. The sample was weighed, and it measured nominally 165 grams per square meter (gsm).

The rail segments were capped using the method described in U.S. Pat. No. 5,868,987 (Kampfer) to produce caps having peaks and grooves. The web was slit into strips having a width of 9 mm. When tested by hand by folding a strip onto itself, the fastener was easy to close and had sufficient resistance to peel open. The thickness in this closed configuration was measured to be 723.9 micrometers. After capping the taller rails, the fastener was bonded to a multi-layer polyolefin packaging film using a heat press at 250 °F (121 °C). The bond strength between the fastener and the packaging film was deemed adequate since cohesive failure in the layers of the packaging film was observed when removal of the fastener was carried out by hand. Dimensions of the fastener are provided in Table 1, below.

Example 2: Fastener as shown in FIG. 3 A

A tool roll as described above was used to create a structure of tall and short repeating continuous ribs. Protrusions in the rib-forming grooves were used to improve polymer filling of the continuous rails the low nip pressure. Example 2 was made using the same materials and method as Example 1. The sample was weighed, and it measured 190 gsm. The thickness of the fastener when it was folded over onto itself to engage the capped rails was measured to be 731 micrometers. Dimensions of the fastener are provided in Table 2, below.

Illustrative Example 3: Fastener as shown in FIG. 6A with caps having peaks and grooves

A tool roll as described above had a combination of cavities for providing rail segments and cavities for providing posts having different heights, with the cavities providing the rail segments being deeper than the cavities providing the posts. Illustrative Example 3 was made using the same material and method as Example 1. The thickness of the fastener when it was folded over onto itself to engage the rail segments was measured to be 636 micrometers. Dimensions of the fastener are provided in Table 1, below.

Example 4: Fastener as shown in FIG. 5

A tool roll surface was created having cavities to provide discontinuous rail segments, posts, and a section with continuous ribs with notches. Example 4 was carried out using the materials and methods of Example 1. The straight continuous ribs shown in FIG. 5 were uncapped by design as the ribs were shorter than the rail segments before capping.

When this example was attempted without protrusions in the cavities forming continuous ribs, ribs having a height of 150 micrometers or less were formed, instead of the heights of 419 or 413 micrometers shown in Table 1, below. Table 1

a) The distance between notches in the ribs was 1.400 millimeters (mm) b) The distance between notches in the capped rails was 1.385 mm. c) The distance between notches in the ribs was 1.400 mm. Examples 1 and 2 and Illustrative Example 3 were evaluated using the Air Seal Measurement Method described above. The results are shown in Table 2, below.

Table 2

Illustrative Example A

To assess whether fastener member designs can be in the fastened and unfastened configurations one or more times without destroying the functionality of the fastener, a Finite Element Model (FEM) was developed to capture the effects of system deformation on plastic strain generation in the features. The commercial code Abaqus 2017 by Simulia was utilized to facilitate modeling tasks. A Standard analysis method was utilized to capture steady state deformation results without considering inertial effects. Two representative units of fastener members were placed in an unfastened configuration, then displaced towards one another until full engagement occurred. A frictionless contact definition was established at the physical interface of the two fastener member units. An elastic-plastic material definition was utilized with a Young’s Modulus of 21,755 psi, a Poissons’ ratio of 0.33, a plastic yield strain of 10.6%, a yield stress of 2320 psi, an ultimate strain of 50% and an ultimate stress of 2900 psi.

The strain results at nodes dispersed throughout the deformable mesh were monitored for a transition into plastic strain (irreversible deformation). Log Strain (True Strain) results of a Finite Element Model of a representative rail and post construction are shown in FIG. 7A. Strain contours are illustrated on the surface ranging from a minimum strain (white) to a maximum strain (black). FIG. 7A shows the fastening system construction in its maximum deformation state with 11.19% strain. FIG. 7B shows the fastening system construction in its final fastened state with a maximum residual strain of 0.69%.

Illustrative Example B

A FEM was developed using the definitions of Illustrative Example A. Similar fastening features were used in this model in a capped rail to capped rail system construction. The fastening features are illustrated in FIG. 8 in their final fastened state. The nominal strain state in the final fastened

configuration results in 20.15% permanent plastic deformation, which may reduce the fastener’s useful lifetime. Various modifications and alterations of this disclosure may be made by those skilled the art without departing from the scope and spirit of the disclosure, and it should be understood that this disclosure is not to be unduly limited to the illustrative embodiments set forth herein. All patents and patent applications cited above are hereby incorporated by reference into this document in their entirety.