In-mold fastener products

Abstract

The in-mold fastener product (30) is made by forming a longitudinally continuous hook strip (10) having a flexible base (12) and male contact fastener elements (14) extending from the upper surface (16) of the base. A layer of flexible separator material (22) is formed on the upper surface of the base such that the fastener elements are embedded in the separator material layer. The separator material (22) is cut to form a pattern of patches (24) of separator material spaced apart and surrounded by a continuous grid (26) of separator material. The grid is peeled from the surface (16) of the base to expose the areas (32) of the base between the patches, and the hook strip is cut along the exposed areas (32) of the base to form individual in-mold fastener products (30), each product having a patch (24) of separator material surrounded by an exposed base edge area (32) carrying the contact fastener elements (14).

Description

Technical Field

[0001] The present invention relates to the manufacture and use of in-mold fastener products, such as those provided on the surface of a molded foam pad to retain a pad cover. Background Art

[0002] Detachable fasteners are used in the manufacture of automotive seats to attach a upholstered seat cover (sometimes referred to as a trim cover) to a polyurethane foam block. During the foam molding process, a portion of the detachable fastener is incorporated into the surface of the polyurethane seat block and is commonly referred to as an "in-mold" product since it is molded into the foam. The mating portion of the detachable fastener is attached to the seat cover to provide a releasable attachment to the foam seat block. The detachable fastener assembly for incorporation in the block surface in a foam mold is typically the hook portion of a detachable fastener system. The hook portion has a base that carries an elastic fastener element or hook on one surface. By various configurations known in the art, the surface of the base facing the hook-carrying surface can be used as an anchoring surface. In some assemblies, a magnetic attraction material is attached to the base to facilitate placement of the assembly in a slot in the wall of a mold cavity equipped with a magnet. A protective layer, typically in the form of a thin plastic film, is placed over the elastic hooks or over a washer surrounding the hooks to prevent foam intrusion into the hooks during the molding process. Excessive foam contamination of the hooks can affect their ability to engage the mating portion of the fastener. This fastening device is applied to one surface of a clamshell mold; a chemical mixture typically consisting of a diisocyanate and a polyol is injected into the mold. As is known in the art, when the chemicals react and foam to form a flexible foam, the upper surface of the mold is closed and clamped. Summary of the Invention

[0003] One aspect of the present invention features a method of manufacturing an in-mold fastener product. The method includes cutting a layer of flexible spacer material on the surface of a longitudinally continuous hook strip having a flexible base and an array of discrete male contact fastener elements extending from the base surface to form a pattern of flexible spacer material patches spaced apart and surrounded by a continuous grid of the spacer material, each patch and grid engaging a male contact fastener element. The grid is peeled from the surface of the base to expose the male contact fastener elements surrounding each patch of flexible spacer material in the exposed area of the base, and the hook strip is cut along the exposed area of the base to form individual in-mold fastener products, each fastener product having a patch of flexible spacer material surrounded by an exposed base edge region carrying a male contact fastener element.

[0004] In some cases, the method includes forming a layer of flexible spacer material on the surface of the base before cutting the layer of flexible spacer material such that the male contact fastener elements are at least partially embedded in the layer of flexible spacer material. In some examples, forming the layer of flexible spacer material includes extruding a continuous stream of spacer material onto the base surface and allowing the extruded stream of spacer material to solidify. In some applications, the layer of flexible spacer material is formed to have a thickness measured from the base surface sufficient to completely cover the embedded male contact fastener elements. In some cases, the layer of flexible spacer material is formed to encapsulate the heads of the male contact fastener elements.

[0005] In some embodiments, the method includes forming a longitudinally continuous hook strip before forming the layer of flexible spacer material. For example, forming a longitudinally continuous hook strip can include forming a flexible base against the surface of a rotomolding roll while molding at least the shanks of the male contact fastener elements in discrete cavities defined in the molding roll and then peeling the flexible base from the molding roll surface to remove the molded shanks from the cavities. The cavities can be shaped to mold the shanks and heads of the male contact fastener elements.

[0006] In some cases, each patch and grid contains embedded male contact fastener elements.

[0007] The flexible spacer material can include, for example, elastomers, polyvinyl chloride, and / or fabric sheets.

[0008] The flexible spacer material can include a magnetically attractive material, for example in the form of particles suspended in a resin matrix.

[0009] In some cases, the hook strip includes a magnetically attractive material, for example in the form of a continuous wire.

[0010] In some examples, each male contact fastener element has a shank formed continuously with the base surface and a head disposed at the distal end of the shank and projecting beyond the base surface.

[0011] Preferably, the ratio of the maximum transverse length to the minimum transverse length of the patch of flexible spacer material is between 1.0 and 10.

[0012] Cutting the flexible spacer material can include die-cutting through the flexible spacer material without cutting through the flexible base of the hook strip.

[0013] Cutting the hook strip can include die-cutting the flexible base of the hook strip between patches of the flexible spacer material.

[0014] Another aspect of the present invention features another method of manufacturing an in-mold fastener product. The method includes forming a layer of flexible spacer material on the surface of a longitudinally continuous hook tape, the hook tape having a flexible base with longitudinal edges and an array of discrete male contact fastener elements extending from the base surface such that at least some of the male contact fastener elements are at least partially embedded in the flexible spacer material layer, cutting the flexible spacer material layer to form a continuous patch of flexible spacer material that extends along a central portion of the longitudinally continuous hook tape and is spaced from the longitudinal edges of the flexible base, and cutting through the longitudinal edges of the hook tape to form notches that extend toward the center of the hook tape.

[0015] In some embodiments, cutting the fastener material layer also forms two spacer material strips that extend along the longitudinal edges of the base and are spaced apart by the continuous patch of spacer material. The method further includes peeling the spacer material strips from the surface of the base to expose the male contact fastener elements in the exposed edge regions of the base.

[0016] In some cases, cutting the spacer material layer forms notches at the longitudinal edges of the continuous patch that are aligned with the notches formed by cutting through the longitudinal edges of the hook tape.

[0017] Another aspect of the present invention features another method of manufacturing an in-mold fastener product. The method includes cutting a layer of flexible spacer material on the surface of a longitudinally continuous hook tape, the hook tape having a flexible base with longitudinal edges and an array of discrete male contact fastener elements extending from the base surface, to form at least one patch of flexible spacer material between two spacer material strips that extend along the longitudinal edges of the base, engaging the at least one patch and the strips with the male contact fastener elements, peeling the spacer material strips from the surface of the base to expose the male contact fastener elements in the exposed edge regions of the base, and cutting through the longitudinal edges of the hook tape to form notches that extend toward the center of the hook tape.

[0018] In some cases, cutting through the longitudinal edges of the hook tape includes forming pairs of longitudinally aligned notches separated by segmented bridges.

[0019] In some examples, cutting through the longitudinal edges of the hook tape includes cutting through the longitudinal edges of at least one patch.

[0020] The flexible spacer material layer can be cut before cutting through the longitudinal edges of the hook tape.

[0021] The spacer material strips can be peeled before cutting through the longitudinal edges of the hook tape.

[0022] Another aspect of the present invention is characterized by a method of forming a seat cushion. The method includes placing a contact fastener product against the inner surface of a mold cavity. The contact fastener includes a sheet of flexible hook tape that carries an array of contact fastener elements extending from the surface of the flexible hook tape. The surface has a central region and an edge region surrounding the central region. In the central region, the contact fastener elements are embedded in a patch of flexible spacer material, and in the edge region, the contact fastener elements are exposed around the central region. The contact fastener product is placed such that the patch of flexible spacer material abuts the inner surface and the exposed contact fastener elements face the inner surface. A flowable expandable resin is introduced into the mold cavity such that the expandable resin expands and flows around the exposed contact fastener elements. The expanded expandable resin is allowed to cure into a molded foam cushion, and the molded foam cushion is removed from the mold cavity.

[0023] In some embodiments, the patch of flexible spacer material is exposed on the surface of the removed molded foam cushion. The method may further include peeling the patch of flexible spacer material from the surface of the flexible hook tape to expose the embedded contact fastener elements, leaving a sheet of flexible hook tape fixed to the cushion with its edge region embedded in the molded foam.

[0024] In some cases, when the molded foam cushion is removed, the patch of flexible spacer material remains on the inner surface of the mold cavity.

[0025] Another aspect of the present invention is characterized by an in-mold fastener product. The product includes a hook sheet and a flexible spacer material layer. The hook sheet has a flexible base and an array of discrete male contact fastener elements extending from the upper surface of the base. The male contact fastener elements extend in a central region of the upper surface and an edge region of the upper surface. The flexible spacer material layer is disposed on the upper surface of the base, and the male contact fastener elements in the central region of the upper surface are embedded in the flexible material layer. On either side of the flexible spacer material layer, the male contact fastener elements in the edge region of the upper surface of the base are exposed.

[0026] In some embodiments, both the flexible base and the flexible spacer material layer define notches extending into the central region of the upper surface.

[0027] The flexible spacer material layer may include a resin layer in which the heads of the male contact fastener elements are encapsulated.

[0028] The flexible spacer material layer may include a fabric in which the heads of the male contact fastener elements are embedded.

[0029] The flexible spacer material layer may be completely surrounded by the edge region that contains the exposed male contact fastener elements.

[0030] In some examples, the hook sheet is in the form of an elongate strip, and the edge regions are disposed along two opposite longitudinal edges of the elongate strip.

[0031] In some cases, the flexible base has a cut resin edge.

[0032] The flexible spacer material is preferably attached to the hook strip only by the embedded contact fastener elements and can be removed by peeling the flexible spacer material from the hook strip without damaging the embedded contact fastener elements.

[0033] In some configurations, a flexible spacer material layer is disposed on the upper surface of the flexible base, and the embedded contact fastener elements are completely encapsulated in the flexible spacer material layer.

[0034] In some cases, the upper surface between the flexible spacer material layer and the embedded contact fastener elements is in direct contact.

[0035] Preferably, the minimum width of the exposed base edge region measured from the patch of the flexible spacer material is between 2% and 20% of the minimum lateral extent of the flexible spacer material patch.

[0036] Aspects of the present invention can provide a fastening function for a molded product (such as a vehicle seat cushion) provided by an in-mold product, which can be produced and used at a low unit cost, and since the foam encapsulates the fastener elements exposed at its edges, allowing other fastener elements to be exposed for engagement, the in-mold product can be well anchored within the cushion. The disclosed method can produce a large number of discrete in-mold formed products using an advantageous low-cost continuous process.

[0037] Details of one or more embodiments of the invention are set forth in the accompanying drawings and the following description. Other features, objects, and advantages of the invention will become apparent from the description, drawings, and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 is a perspective view of a portion of a longitudinally continuous hook strip.

[0039] Figure 2 is a schematic diagram of a method and apparatus for forming an in-mold fastener product.

[0040] Figure 3 is the hook strip with Figure 1 a layer of spacer material applied.

[0041] Figure 4 is Figure 3 a perspective view of a portion of the hook strip and the applied spacer material, where the spacer material is die-cut into patches.

[0042] Figure 5 shows the spacer material grid peeled from the Figure 4 product.

[0043] Figure 6 is a perspective view of a single fastener product cut from the product shown Figure 5 in

[0044] Figure 6A is an end view of a hook strip having a patch of insulating material formed as a head encapsulating some fastener elements

[0045] Figure 6B is a sectional view taken along line 6B - 6B Figure 6A shown

[0046] Figure 7 is a partial sectional view of the product Figure 6 held against the inner mold surface

[0047] Figure 8 shows the product Figure 7 after the mold has been filled with foam around the product to form a seat cushion

[0048] Figure 9 shows a patch of insulating material peeled from the product in the surface of the molded seat cushion

[0049] Figure 10 is a sectional view through the product in the surface of the molded foam seat cushion

[0050] Figure 11 is a perspective view of an intermediate hook strip in which a strip of insulating material extends along the central portion of the hook strip

[0051] Figure 12 is a fastener product formed by die - cutting Figure 11 the intermediate hook strip

[0052] Figure 13 is a perspective view of a covering pre - formed strip of the fastener product showing the die - cut pattern

[0053] Figure 14 is a partial end view of the fastener product in which the fastener elements are embedded in a textile fabric cover in a central region

[0054] Like reference numerals in different figures represent like elements DETAILED DESCRIPTION

[0055] Referring initially to Figure 1 , the hook strip 10 is longitudinally continuous in the machine direction indicated by the arrow MD and has a limited width in the cross - direction. The hook strip 10 has a flexible base 12 and an array of discrete male contact fastener elements 14 extending from the upper surface 16 of the base Figure 1The belt shown is not to scale. The thickness 't' of the base can be, for example, between 0.1 and 0.4 mm, and the width of the belt in the transverse direction can be 600 mm or greater, while in many applications the width will be between 150 and 650 mm. The hook belt 10 is formed of a thermoplastic resin (such as polyamide or polypropylene), and partly due to its small thickness, it is very easy to bend out of its plane. The male contact fastener element 14 is schematically shown as a J-shaped hook, but can be any of a variety of shaped contact fastener elements for releasably hooking fibers to form a fastening, such as a single hook, a two-way (palm tree) hook, a mushroom-shaped fastener element with a head that overhangs the stem in all directions, etc. As shown, the male contact fastener elements 14 can be arranged in columns extending in the machine direction, and adjacent columns can be staggered relative to each other and have hooks facing in opposite directions. Each male contact fastener element has a stem 18 formed continuously with the upper surface 16 of the base 12 and a head 20 disposed at the distal end of the stem and overhanging the upper surface of the base. The male contact fastener element 14, shown enlarged for purposes of illustration, is set in an array having a male contact fastener element density between 75 and 200 elements per square centimeter, and a height measured from the upper surface of the base of only about 0.3 to 2.5 mm. Preferably, the male contact fastener element density is at least constant across the width of the hook belt, and more preferably is constant across the width and along the length of the hook belt.

[0056] Reference Figure 2 , the hook belt 10 can be formed, for example, by a continuous roll forming process such as that initially taught by Fischer in US 4,775,310, the content of which regarding roll forming methods and apparatus is incorporated herein by reference. In such a process, the flexible base is formed against the surface of a rotating molding roll 50 while at least the stem (or stem and head) of the male contact fastener element is molded in discrete cavities defined in the molding roll. The flexible base is then peeled from the surface of the molding roll, thereby removing the molded stem (or stem and head) from the cavities. The molding roll can be one of a pair of counter-rotating rolls 50 and 52 defining a pressure roll nip 54 in which a flowable resin 56 is pressed into the cavities so as to continuously form the fastener element stem with the surface of the base formed against the surface of the molding roll. In some cases, a preform material 58 (such as a continuous scrim or other fabric) is introduced into the nip together with the resin such that the preform material is laminated to or possibly embedded in the flexible base, as taught by Kennedy in US 5,260,015, the content of which patent relates to in-situ lamination of preform materials during hook molding, the patent being incorporated herein by reference. The roll nip conditions can be adjusted such that at least a portion of the preform material extends from the back side of the hook belt to form an adhesive layer for bonding to foam.

[0057] Also referring toFigure 3 , after the hook strip 10 is formed, a layer of flexible separator material 22 is formed on the upper surface of the base such that the male contact fastener elements are embedded in the flexible separator material layer. Preferably, the embedded contact fastener elements are completely encapsulated in the flexible separator material layer 22, and the flexible separator material layer is formed to have a thickness "T" measured from the upper surface of the base, sufficient to completely cover the embedded male contact fastener elements and the flexible separator material layer 22 in direct contact with the upper surface between the embedded contact fastener elements. Preferably, the flexible separator material 22 is attached to the hook tab 12 only by the embedded contact fastener elements and can be removed by peeling the flexible separator material from the hook tab without damaging the embedded contact fastener elements. The separator material can be extruded, for example, from an extruder 60 onto the hook strip and can be pressed against the hook strip in a nip 62 of fixed thickness, the nip 62 controlling the thickness of the separator material and helping to eliminate voids.

[0058] The flexible separator material 22 can be an elastomer, such as polyvinyl chloride, which can be extruded onto the upper surface of the base as a continuous stream and allowed to solidify. The separator material can be in the form of a high-density closed-cell foam that solidifies when the strip is pulled through a closed channel 64 (or nip between rollers) that restricts the expansion of the foam. In the case where the hook strip is formed of a thermoplastic resin, the flexible separator material should have a lower melting temperature than the hook strip resin so that the contact fastener elements and the base surface are not significantly altered by the introduction of the separator material. Preferably, the separator material is selected such that when the hook strip resin solidifies, the separator material does not chemically bond, or only slightly bonds, to the hook strip resin so that the separator material can be peeled from the hook strip without damaging the hook strip. For example, a blowing agent can be added to a polyvinyl chloride or polyethylene separator resin, or a thermosetting separator foam can be used. Selecting a separator material with a melting point far from the melting point of the hook strip resin also helps to avoid bonding.

[0059] The flexible separator material 22 preferably contains a magnetically attractable component, such as iron powder distributed within the material. The flexible separator material can include, for example, 10 - 20% by weight of iron powder with a particle size in the range of 45 - 320 microns.

[0060] Next, refer to Figure 2 and Figure 4, after the flexible spacer material 22 has solidified on the hook tape, both are conveyed through a cutting station 66 where the flexible spacer material 22 is cut to form a pattern of patches 24 of flexible spacer material separated and surrounded by a continuous grid 26 of spacer material, each patch and grid containing embedded male contact fastener elements. For example, the flexible spacer material 22 can be cut by die-cutting through the flexible spacer material without cutting through the flexible base of the hook tape, such as by running the material through a die-cutting station with a die-cutting roller 68 having a pattern of blades 70 extending from its surface, the pattern of the blades corresponding to the pattern of the patches. To facilitate subsequent processing, the die-cutting depth should be chosen to penetrate substantially through the spacer material layer and even slightly into the hook tape base, but not so deep into the base as to cause the base to separate at the edges of the patches in subsequent steps.

[0061] The patches 24 are preferably cut completely around their outer perimeters, and the grid 26 should completely surround each patch. For illustrative purposes, the patches 24 are shown as rectangles in Figure 4 but in practice the patches 24 will be formed to have a desired shape such as a fastening area of a seat cushion. In many cases, the patches will not be in the form of narrow bands but will be shaped such that the area they cover will present a wide fastening area. The ratio of the maximum lateral extent to the minimum lateral extent of a patch 24 of flexible spacer material can be, for example, between 1.0 and 10. In the cutting of the spacer material, the position of individual male contact fastener elements does not need to be considered. At the location where the spacer material is cut, individual male contact fastener elements may be damaged or destroyed, but sufficient functional male contact fastener elements will remain encapsulated in the spacer material, in the patches and in the grid.

[0062] Next refer to Figure 2 and Figure 5 , and then the grid 26 is peeled from the upper surface 16 of the base 12 to expose the male contact fastener elements 14 in the exposed areas of the base surrounding each patch 24 of flexible spacer material 22. When the grid 26 is peeled and reprocessed, the patches 24 remain in place. Also, the features shown are not drawn to scale. For example, in the width of the exposed areas between the patches 24, there will typically be at least one row or column of male contact fastener elements, and in some cases 4 to 6 rows or columns. And because the patches are generally not rectangular in shape, the exposed areas of the base will vary across the material and along the width of the material. The grid 26 should be peeled into a continuous sheet of holes presenting small holes 28 on the underside of the grid where the grid is peeled from the individual male contact fastener elements.

[0063] Next refer to Figure 2 and 6, after the grid of the spacer material is removed, the hook strip is cut along the exposed area of the base to form individual in-mold fastener products 30, each fastener product 30 having a patch 24 of flexible spacer material 22 surrounded by an exposed base edge area 32 of the carrier of the male contact fastener elements 14. In many cases, the hook strip will be cut so that the base edge area 32 has a substantially constant width around the patch 24 and contains at least one row or column of spaced-apart male contact fastener elements 14 across its width at any point around the patch perimeter. Preferably, the exposed base edge area 32 has a minimum width measured from the flexible spacer material patch that is between 2% and 20% of the minimum lateral extent of the flexible spacer material patch. Note that, for purposes of illustration, the number of exposed male contact fastener elements has been reduced.

[0064] The cutting of the hook strip can be achieved by die-cutting the flexible base 12 of the hook strip between the patches 24 of the flexible spacer material, for example at a second die-cutting station 66a, to form a cut base edge around the outer perimeter of each fastener product 30. The fastener products can be completely separated from the surrounding grid of the hook strip, for example by punching them out of the plane of the running strip at a separation station 72, and can be placed in packaging for shipment to the customer. Alternatively, the die-cutting blade pattern at the die-cutting station 66a can be arranged to leave a small bridge of the hook strip base that connects each fastener product to the surrounding grid, and the grid and the products are wound together into a continuous strip for transportation and subsequent separation. As with the cutting of the spacer material, the cutting of the hook strip can be done regardless of the position of the male contact fastener elements. Some of the male contact fastener elements will be damaged or destroyed at the cut edges of the fastener products, but a sufficient number of male contact fastener elements 14 will remain in the exposed base edge area 32. Thus, as Figure 6 shown, each fastener product 32 includes a sheet of flexible hook strip 10 that carries an array of contact fastener elements 14 extending from the surface of the flexible hook strip, the surface including a central area 33 and an edge area 32 surrounding the central area, in the central area 33, the contact fastener elements are embedded in a patch 24 of flexible spacer material, and in the edge area 32, the contact fastener elements 14 are exposed.

[0065] Next refer to Figure 6A and 6B , in some cases, the spacer material 22 is not formed to extend all the way to the surface 16 of the base 12, but only encapsulates the heads 20 of the fastener elements 14, leaving portions of the shanks 18 exposed. Preferably, the gap thickness between the base surface and the spacer material is small enough that the foam that intrudes between the fastener element shanks will cool and will not intrude beyond the few rows of fastener elements closest to the patch edge, or will at least leave the heads with sufficient functionality to engage and hold the loops when the spacer material is removed.

[0066] Next, referring to Figure 7 , the single contact fastener product 30 formed by the above method can be placed against the inner surface 34 of the mold cavity 36. The contact fastener product 30 is placed such that the flexible spacer material patch 24 abuts the inner surface 34, and the exposed contact fastener elements 14 face the inner surface. The patch 24 is attracted by the magnet 38 embedded in the mold inner surface 34, and the magnet 38 holds the contact fastener product firmly in place when the foam is molded in the cavity. It is noted that depending on the thickness of the patch 24, the male contact fastener elements in the base edge region 32 exposed around the patch are exposed at the edge of the contact fastener product and can remain slightly spaced from the mold surface.

[0067] Next, referring to Figure 8 , with the contact fastener product 30 held in place against the mold cavity surface, the expandable resin stream is introduced into the mold cavity such that the expandable resin expands and flows around the exposed contact fastener elements 14, effectively encapsulating the exposed base edge region 32 (including its contact fastener elements) of the contact fastener product in the foam. The expandable resin is allowed to cure into a molded foam pad having the contact fastener product secured to the surface of the pad. The molded foam pad is then removed from the mold cavity.

[0068] Next, referring to Figure 9 and 10 , in some cases, when the molded foam pad 40 is removed from the cavity, the patch 24 of the flexible spacer material will remain attached to the hook strip 10. In this case, the patch will be exposed on the surface of the molded foam pad and can be peeled from the surface of the flexible hook strip 10 to expose the embedded contact fastener elements 14, leaving the flexible hook strip patch secured to the pad with its edge region embedded in the molded foam.

[0069] In some other cases, the magnetic attraction of the patch will be sufficient to keep the patch against the mold surface when the molded pad is removed. In this case, the patch will be removed separately from the mold cavity and discarded.

[0070] In either case, the spacer material will desirably be selected to not form a strong bond with the pad foam resin such that the patch will easily separate from the molded foam without pulling the foam away from the embedded edge region of the hook strip. Removing the patch will leave the molded foam surface 42 facing the now-exposed central region 33 of the hook strip 10, where the male contact fastener elements 14 that were embedded in the patch are exposed and unobstructed to engage the fibers on the underside of a pad sleeve (not shown), thereby holding the sleeve to the pad.

[0071] Next, referring to Figure 11 and 12, the strip-shaped in-mold fastener product can be formed in a similar manner, for example, by first forming the spacer material 22 to cover at least the central portion of the longitudinal continuous strip of the hook strip 10, and then cutting through the longitudinal edges 44 of the flexible base 12 of the hook strip to form notches 46 extending toward the center of the hook strip. In some cases, the notches are also cut through the longitudinal edges 48 of the longitudinal patch 24 of the spacer material, and the longitudinal patch 24 is spaced from the longitudinal edge of the flexible base. Opposing pairs of notches are separated by narrow bridges 80 that connect segments of adjacent hook strips defined between the pairs of notches. The notches allow the strip-shaped hook strip to bend in its plane, for example, following the curvature of the grooves in the mold.

[0072] In some cases, the spacer material is formed to extend across the entire width of the hook strip, as Figure 2 shown, and cutting through the spacer material layer also forms two strips of spacer material ( Figure 11 not shown in the figure), which two strips of spacer material extend along the longitudinal edges of the base and are separated by a continuous patch of spacer material. As Figure 11 shown, the strips of spacer material are then peeled from the base surface to expose male contact fastener elements in the exposed edge regions of the base.

[0073] In some cases, the spacer material layer is die-cut to separate the continuous patch from the strip 82, as Figure 13 shown, and the die-cutting follows the contour of the notch 46 that has been or will later be cut through the edge of the hook strip, or the contour of the notch 46 that is being cut through the edge of the hook strip simultaneously, for example, by cutting with die wheels aligned from opposite sides of the hook strip. In any order, what remains is Figure 12 a strip-shaped product that can be placed along the elongated grooves in the foaming mold, and the spacer material patch not only protects the embedded hooks from foam intrusion, but also cooperates with magnets embedded in the mold wall along the grooves to provide an attractive force to hold the product in place during foaming. After foaming, the exposed edge regions 84 of each longitudinal segment are encapsulated in the foam, and the exposed fastener elements in these regions help to anchor the product in place. Then, the spacer material patch 24 can be peeled from the surface of the hook strip to expose the fastener elements along the central region for engagement.

[0074] In the above example, the spacer material is characterized by a continuous resin layer that at least encapsulates the heads of the fastener elements during the molding of the fastener product into a foam product such as a seat cushion, and is subsequently peeled off after the fastener product has been molded into a foam product such as a seat cushion. Refer to Figure 14, the spacer material may alternatively be in the form of a fabric layer 86, with the fastener element head embedded in the fabric layer 86 and preventing foam intrusion around the head during foaming. The fabric layer may be in the form of, for example, a non-woven material with a paper backing 88, and the non-woven material is adhered to the paper backing 88. The fabric layer 86 may be applied to the hook side of the hook tape to cover the entire width of the tape, and then die-cut and peeled from the edge region of the tape to expose the fastener element along the hook tape edge, as described above with respect to Figures 11 - 13 described, the hook tape edge has notches or no notches, or may be die-cut to form spaced-apart patches and grids, as described above with respect to Figures 4 - 6 described. After foaming, the patch of fabric covering the fastener element may be peeled off to expose the fastener element for use. Any foam that intrudes under the patch edge and into the fabric layer may be peeled off with the fabric. A magnetically attractive material such as a wire (not shown) may be provided between the fabric and the paper backing for holding the product in the mold.

[0075] While multiple examples have been described for illustrative purposes, the foregoing description is not intended to limit the scope of the invention, which is defined by the scope of the appended claims. There will also be other examples and modifications within the scope of the appended claims.

Claims

1. A method of manufacturing an in-mold fastener product, the method comprising cutting a layer of flexible release material (22) on the surface of a longitudinally continuous hook tape (10), the hook tape having a flexible base (12) and an array of discrete male contact fastener elements (14) extending from the surface (16) of the base, the male contact fastener elements (14) being at least partially embedded in the layer of flexible release material (22) to form a pattern of patches (24) of flexible release material (22) spaced apart and surrounded by a continuous grid (26) of flexible release material, each of the patches and the grid engaging the male contact fastener elements (14); peeling the grid (26) from the surface of the base (12) to expose the male contact fastener elements (14) in the exposed area (32) of the base, the exposed area surrounding each patch of flexible release material; and cutting the hook tape along the exposed area of the base (12) to form individual in-mold fastener products (30), each in-mold fastener product (30) having a patch (24) of flexible release material (22) surrounded by an exposed base edge area (32) carrying the male contact fastener elements (14).

2. The method according to claim 1, further comprising forming the layer of flexible release material (22) on the surface (16) of the base (12) before cutting the layer of flexible release material (22), such that the male contact fastener elements (14) are at least partially embedded in the layer of flexible release material (22).

3. The method according to claim 2, wherein forming the layer of flexible release material (22) comprises extruding a continuous stream of release material onto the surface (16) of the base (12) and allowing the extruded stream of release material to solidify.

4. The method according to claim 3, wherein the layer of flexible release material (22) is formed to encapsulate the heads (20) of the male contact fastener elements (14).

5. The method according to claim 2, further comprising, before forming the layer of flexible release material (22), forming a longitudinally continuous hook tape (10).

6. The method according to claim 5, wherein forming the longitudinally continuous hook tape (10) comprises forming a flexible base (12) against the surface of a rotatable molding roll (50) while molding at least the shanks (18) of the male contact fastener elements (14) in discrete cavities defined in the molding roll, and then peeling the flexible base (12) from the molding roll surface, thereby removing the molded shanks (18) from the cavities.

7. The method according to claim 6, wherein the cavities are shaped to mold the shanks and heads of the male contact fastener elements (14).

8. The method according to claim 7, wherein each of the male contact fastener elements (14) has a shank (18) formed continuously with the surface (16) of the base (12) and a head (20) disposed at the distal end of the shank and overhanging the base surface.

9. The method according to claim 1, wherein each of said patches (24) and said grid (26) comprises an embedded male contact fastener element (14).

10. The method according to claim 1, wherein said flexible spacer material (22) comprises an elastomer, or wherein said flexible spacer material comprises a fabric sheet.

11. The method according to claim 1, wherein said flexible spacer material comprises polyvinyl chloride.

12. The method according to claim 1, wherein said hook strip (10) comprises a magnetically attractive material.

13. The method according to claim 12, wherein said hook strip (10) comprises a magnetically attractive material in the form of a continuous wire.

14. The method according to claim 1, wherein said flexible spacer material (22) comprises a magnetically attractive material.

15. The method according to claim 14, wherein said flexible spacer material (22) comprises a magnetically attractive material in the form of particles suspended in a resin matrix.

16. The method according to claim 1, wherein the ratio of the maximum lateral extent to the minimum lateral extent of each patch (24) of flexible spacer material is between 1.0 and 10.

17. The method according to claim 1, wherein cutting said flexible spacer material (22) comprises die-cutting through said flexible spacer material (22) without cutting through the flexible base (12) of said hook strip (10).

18. The method according to claim 1, wherein cutting said hook strip (10) comprises die-cutting through the flexible base (12) of the hook strip between patches (24) of flexible spacer material.

19. A method of forming a seat cushion (40), the method comprising placing a contact fastener product (30) against an inner surface (34) of a mold cavity (36), said contact fastener product comprising a sheet of flexible hook strip (10) carrying an array of contact fastener elements (14) extending from a surface (16) of said flexible hook strip, said surface comprising a central region (33) and an edge region (32) surrounding said central region, in said central region, said contact fastener elements being embedded in patches (24) of flexible spacer material (22), in said edge region, said contact fastener elements being exposed, said contact fastener product being placed such that patches (24) of flexible spacer material (22) are against the inner surface (34) and the exposed contact fastener elements (14) face the inner surface; introducing a flow of expandable resin into said mold cavity (36) such that the expandable resin expands and flows around the exposed contact fastener elements (14); allowing the expanded expandable resin to cure into a molded foam cushion (40); and removing the molded foam cushion (40) from said mold cavity (36).

20. The method according to claim 19, wherein patches (24) of said flexible spacer material (22) are exposed at a surface of the removed molded foam cushion (40).

21. The method according to claim 20, wherein when the molded foam cushion (40) is removed, patches of flexible spacer material remain at the inner surface (34) of said mold cavity (36).

22. The method according to claim 21 further comprises peeling a patch (24) of flexible release material from a surface (16) of the flexible hook tape (10) to expose the embedded contact fastener elements (14), leaving the flexible hook tape (10) with the patch fixed to the pad (40), the edge region (32) being embedded in the molded foam.

23. An in-mold fastener product (30) comprising a hook piece having a flexible base (12) and an array of discrete male contact fastener elements (14) extending from an upper surface (16) of the base in a central region (33) and an edge region (32) of the upper surface; and a layer of flexible release material (22) disposed on the upper surface of the base, the male contact fastener elements (14) in the central region (33) of the upper surface being embedded in the layer of flexible release material (22); wherein the male contact fastener elements (14) in the edge region (32) of the upper surface of the base (12) are exposed on either side of the layer of flexible release material (22).

24. The in-mold fastener product according to claim 23, wherein both the flexible base (12) and the layer of flexible release material (22) define a notch (46) extending into the central region (33) of the upper surface (16), and / or wherein the layer of flexible release material (22) comprises a resin layer in which the heads (20) of the male contact fastener elements (14) are encapsulated, or wherein the layer of flexible release material (22) comprises a fabric in which the heads (20) of the male contact fastener elements (14) are embedded.

25. The in-mold fastener product according to claim 23, wherein the layer of flexible release material (22) is completely surrounded by the edge region (32) containing the exposed male contact fastener elements (14), or wherein the hook piece is in the form of an elongate strip and wherein the edge region (32) is provided along two opposite longitudinal edges (44) of the elongate strip.

26. The in-mold fastener product according to claim 23, wherein the flexible base (12) has a cut resin edge, and / or wherein the flexible release material (22) is attached to the hook piece only by the embedded contact fastener elements (14) and can be removed by peeling the flexible release material (22) from the hook piece without damaging the embedded contact fastener elements (14).

27. The in-mold fastening product according to any one of claims 23 to 26, wherein a layer of the flexible spacer material (22) is provided on the upper surface (16) of the flexible base (12), the embedded contact fastener elements (14) are completely encapsulated in the layer of the flexible spacer material (22), and / or wherein the upper surface (16) between the layer of the flexible spacer material (22) and the embedded contact fastener elements (14) of the flexible base (12) is in direct contact, and / or wherein the minimum width of the exposed base edge region (32) measured from the patch (24) of the flexible spacer material is between 2% and 20% of the minimum lateral extent of the patch of the flexible spacer material.

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