Foam reefer wall backing with spaced rows of loops for better adhesion

Abstract

An improved reefer wall panel having better foam adhesion includes purposefully spaced gaps in the looped sections to be foamed. Such spaced gaps may extend horizontally, vertically, diagonally or in combinations of directions. These gaps (random or patterned) may be applied to the whole of a reefer panel or to just the more vulnerable lower sections where traffic impact during loading/unloading is more common and/or where delamination is known to occur more frequently. A method of reefer panel manufacture with such spaced gaps is also disclosed.

Claims

1. An improved reefer wall panel having better foam adhesion thereto, said wall panel comprising: (a) a woven wall substrate; and (b) a plurality of fully looped sections secured at each loop end of the plurality of fully looped sections into the woven wall substrate, said plurality of fully looped sections adapted for extending in a first direction outwardly beyond the woven wall substrate, said woven wall substrate including one or more rows of purposefully spaced gaps in the plurality of fully looped sections before a thermoplastic resin is injected onto the woven wall substrate and the plurality of fully looped sections to make the reefer wall panel.

2. The reefer wall panel of claim 1 wherein the rows of purposefully spaced gaps extend substantially horizontal in the plurality of fully looped sections.

3. The reefer wall panel of claim 1 wherein the rows of purposefully spaced gaps extend substantially vertical in the plurality of fully looped sections.

4. The reefer wall panel of claim 1 wherein the rows of purposefully spaced gaps extend diagonally in the plurality of fully looped sections.

5. The reefer wall panel of claim 1 wherein the rows of purposefully spaced gaps extend randomly across the plurality of fully looped sections.

6. The reefer wall panel of claim 1 wherein the rows of purposefully spaced gaps extend in a preset pattern across the plurality of fully looped sections.

7. The reefer wall panel of claim 1 wherein the rows of purposefully spaced gaps have no loops extending upwardly from the woven wall substrate.

8. The reefer wall panel of claim 1 wherein at least some of the rows of purposefully spaced gaps include one or more set of loops that are visibly shorter than adjacent loops in the plurality of fully looped sections extending upwardly from the woven wall substrate.

9. The reefer wall panel of claim 1 wherein the rows of purposefully spaced gaps extend in at least one of: high impact areas and high delamination areas of the reefer wall panel.

10. The reefer wall panel of claim 1 wherein the rows of purposefully spaced gaps extend in other than a high impact area or a high delamination area of the reefer wall panel.

11. The reefer wall panel of claim 1 wherein the rows of purposefully spaced gaps range in size from about 1 to 10 inches high or wide.

12. The reefer wall panel of claim 11 wherein the rows of purposefully spaced gaps range in size from about 3 to 5 inches high or wide.

Description

BRIEF SUMMARY OF THE DRAWINGS

(1) Further features, objectives and advantages of this invention will become clearer with the following Detailed Description made with reference to the accompanying drawings in which:

(2) FIG. 1 is a photograph showing currently known scrim with its very small fibers in just the x and y-axes;

(3) FIG. 1A is a photograph showing the standard scrim bond of FIG. 1 with its attached foam partially peeled away;

(4) FIG. 2A is a cross sectional view of a lower half hook and loop tape as used with the present invention;

(5) FIG. 2B is a front plan view of a first embodiment of improved reefer wall having a plurality of hook tape sections applied in a spaced, horizontal arrangement from near the top to near the bottom of the wall prior to foaming;

(6) FIG. 2C is a front plan view of a second embodiment of improved reefer wall having a plurality of hook tape sections applied in a spaced, diagonal arrangement from near the top to near the bottom of the wall prior to foaming;

(7) FIG. 2D is a front plan view of a third, representative embodiment of improved reefer wall with a plurality of circular-shaped hook tape sections applied randomly to just a lower section of the wall (in more vulnerable regions for delaminating) prior to foaming;

(8) FIG. 3 is a diagrammatic representation of one prior art variety of multiple thread/strand fabric inter-looped to one another but with no base connection, per FIG. 3a of U.S. Pat. No. 3,934,064;

(9) FIG. 4 is a diagrammatic representation of a second prior art foam backing system, this time with a single thread/strand having one end into a polymer base but no interweaving therethrough, per FIG. 7 of U.S. Pat. No. 3,934,064;

(10) FIG. 5 is a cross-sectional diagram of a third prior art variety of material showing means for randomly embedding continuous strands of fabric into and at least partially below an innermost layer; but it exhibits no connection on randomness, per FIG. 8A of U.S. Published Application No. 20150246511;

(11) FIG. 6 is a cross-sectional diagram of a fourth prior art variety of material showing embedding strands of fabric with multiple downward extensions (in one common direction) from its innermost layer, per FIG. 8B of U.S. Published Application No. 20150246511;

(12) FIG. 7 is a front perspective view showing one system of foam reefer wall according to this invention, said foam reefer wall employing one embodiment of loop scrim fabric backing for improved foam adhesion thereto, all interconnected using one continuous fiber creating base and loop together;

(13) FIG. 7A is a close-up sectional view of the circled area 7A from FIG. 7, showing loops of a substantially uniform or constant height;

(14) FIG. 7B is a cross-sectional view of a first alternative embodiment showing loops with purposefully variable heights, 118a, 118b and 118c;

(15) FIG. 7C is a top perspective view of a second alternative embodiment showing intentional loop gaps in both the horizontal GH and vertical GV directions;

(16) FIG. 7D is a close-up sectional view of the circled area 7D from FIG. 7C;

(17) FIG. 8 is a top perspective photograph showing, from one edge, an embodiment of loop scrim fabric backing per this invention;

(18) FIG. 9 is a close-up diagram showing or how the loops are interwoven into the base per one embodiment of this invention;

(19) FIG. 10 is a close-up diagram focusing on one row of preferred loops with base material per this invention; and

(20) FIG. 11 is a perspective, sectional view of a refrigerated vehicle trailer showing the improved loop scrim fabric backing of this invention installed on the interior of the same.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

(21) When referring to alternate embodiments, like that shown in FIG. 7B, common elements are commonly numbered though in the next hundred series.

(22) When referring to any numerical length, width, percent improvement or other quantitative comparison number (or number range) herein, it should be noted that all such numbers are representative of embodiments of the invention as shown. Furthermore, any such range of numbers should expressly include each and every fraction or decimal between its stated minimum and maximum. For instance, any one component (of loop material) having from about 40 to 70 loops per square inch, should also specifically cover fabric backing substrates having about 41, 42 and 45 loops/in.sup.2 . . . and so on, up to about 65, 67 and 69.6 loops/in.sup.2. And for loop heights between abut 0.5 to 6 mm or more, preferably about 3 to 5 mm each, those loops would include all values between the aforementioned minimum and maximum loop heights. It is to be understood, however, that Applicant considers the mere aspect of creating such looped scrim fabric backing, regardless of loop size/consistency and/or relative loop density to be a truly novel, game-changer aspect of the present invention.

(23) A fabric backing with at least about 30% greater foam adhesion as compared to its scrim counterpart, would also exhibit about 35, 40 and 50%+ improvement. The same applies for every other quantitative range herein.

(24) FIG. 1 shows a 37 magnification of current known standard scrim panel as might be made and sold by Xamax Industries, Matterworks and/or OXCO Industries to name a few. Unfortunately, therein, the underlying panel P had its foam F separated therefrom with the application of nominal pull pressure due to a weakness of adhesion at the interface between as better seen in accompanying FIG. 1A.

(25) Note the following difficulties/disadvantages with that product:

(26) 1) fibers are very smallin only the x- and y-Axes (marked therein);

(27) 2) there are indentations where the fibers have been connected via a heated point bond roller;

(28) 3) it is a much denser productharder to soak into during foaming therefore resulting in worse bonding; and

(29) 4) this point bond product is made of two layers bonded together, which could allow separation. It is especially vulnerable to separation especially when moisture is introduced.

(30) FIG. 1A is a photograph showing a prior art panel P with its standard scrim bond B, like that shown in FIG. 1, when attached to foam F but then that latter foam F is partially peeled away.

(31) Accompanying FIGS. 2A through D shows Applicant's newest development. It exhibits much advancement and improvement over the current scrim of FIG. 1. The underlying material has a plurality of loops extending upwardly therefrom before being combined with foam by injection during the manufacture of trailer and other GRTP materials/component parts. The resulting product exhibits much greater adhesion at its interface.

(32) More particularly, FIG. 2A is a drawing showing a cross section of the lower half of a hook and loop tape T, more often referred to by the name Velcro, with its barbs or hooks H diagrammatically depicted as extending upwardly and along a section of adhesive tape backing. A second section of looped fabric, not shown in this view, would be layered onto the aforementioned hook components and with nominal applied pressure forced into the hooks for readily interlocking therewith. Such connections are reusable, however, as the upper loops can be pulled away from the hooks and then repeatedly rejoined thereto;

(33) FIG. 2B is a drawing showing a first embodiment of improved reefer wall W with a plurality of lateral hook tape sections (l.sub.1 through l.sub.6) applied in a spaced, horizontal arrangement from near the top 10 to near the bottom 20 of wall W prior to the application of foam thereto;

(34) FIG. 2C is a drawing showing a second embodiment of improved reefer wall W with a plurality of hook tape sections (d.sub.1 through d.sub.7) applied in a spaced, diagonal arrangement from left to right, from near the top 10 to near the bottom 20 of wall W prior to the application of foam thereto; and

(35) FIG. 2D is a drawing showing a third, representative embodiment of improved reefer wall W with a plurality of circular-shaped hook tape sections c applied randomly to just a lower section 20 of wall W (in a typically more vulnerable region for delamination or loading damage) prior to the application of foam thereto. These are but three such arrangements, it being understood that still other arrangements of full hook tape, various subsections of hook material (in rectangles, squares, triangles, etc.) may be randomly or purposefully placed about in an orderly pattern prior to foaming. To a lesser degree, the looped partner to such hook sections may be situated about, in place of (i.e., in the alternative) OR in addition to the placement of the hook section tapes there along . . . prior to the addition of foam to these reefer wall units.

(36) Main steps to this invention include: 1) Replacing standard scrim by laminating a PET backing that has a polypropylene film layer on one side and urethane surface on the other side. 2) The urethane surface would face the foam and provide a chemical bond to the urethane foam. 3) Then we would place strategically half of an adhesive backed Velcro or the Vel if you will (i.e., just the male or hook portions of such material) along various points of the wall for better adhesion of foam to these sections of strategically placed Velcro tape halves.

(37) Advantages are that this alternative to the use of full loop sheet material (the subject of its own pending U.S. application, also filed in the name of Applicant) is much cheaper than the aforementioned. These subsections of hook-only strips (or shaped sections) can also be placed on any time after the panel has been laminated thus allowing for a strategic yet inexpensive way to get the foam bond without laminating.

(38) The use of hook tape and/or shaped sections per this invention also avoids the potential for looped only material assists getting buried into the surface like the loop fabric might during lamination. The materials being used hereby only use adhesives per se and do not HAVE TO BE laminated into the surface of the panel in order to bond to it.

(39) Configurations, shapes and angles of VEL are only limited by the requirement of the application. Furthermore, it should be understood that this invention can be practiced on whole wall or just on the bottom sections thereof. There should be no distinction other than the concept of why we are doing this. It should be cheaper than but still just as effective as loop.

(40) Still other advantages of this improved product include:

(41) 1) a fiber loop design that has been woven into a pattern extending far beyond the surface of the panel. That allows for the foam to cure around the loops to the bottom connection point and create a much deeper grab factor. That, in turn, allows for the wall to exceed the surface bond obtained by the current methods of scrim and create a more permanent bond, deep into the cured foam, for solving the delamination issue of prior products.

(42) This is truly a game-changing, MAJOR improvement! When the foam attaches to the wall, the raised loop fibers of this invention will grab and hold much better than just an X and Y axis product. The present invention adds a looped dimension to the equation thus making for an overall stronger interior panel. Even if the standard scrim was lofted or roughed up to provide an exposed Z-fiber, as per accompanying FIG. 6, there is still no loop mechanism equivalent that can provide the mechanical grab and reconnection to an interwoven base/bottom that this concept does.

(43) 2) The design of the new loop has a uniform grid base (loop density can be varied to accommodate different foam compositions and densities) that allows for excellent attachment to applicant's base polypropylene wall and glass mat products so that it holds better.

(44) 3) The loop design is impervious to moisture unlike old scrim material that can separate when wet into two point bond layers from its point bond.

(45) 4) Applicant's polypropylene can soak through this product during the lamination process thereby allowing for a better grab to the trailer interior GRTP wall than the traditional scrim product, a potentially 50%, 75%, even 100% or more adhesion than standard scrim, in fact.

(46) 5) Loop fabric can be applied by either laminating on OR gluing to the backside surface of the wall allowing for maximum optional usages in the field.

(47) 6) Loop fabric can be of any material such as a polyester, nylon, polypropylene, polyethylene, etc., but should be stiff enough to hold its shape without flattening out as the trailer wall is rolled for shipping or placed into a foaming chamber.

(48) One set of preferred method steps for making this improved material product commences with: (a) providing an improved fabric backing substrate having a plurality of loops interwoven therewith; (b) orienting the plurality of loops in the backing substrate to stand in a raised (rather than flattened) condition; and (c) injecting a polymer (preferably, polypropylene) foam about the raised loops for greater impregnation of the polymer into the backing substrate for the manufacture of a trailer scrim/glass-reinforced thermoplastic interior wall panel.

(49) A further novel method entails making an improved storage unit, such as a refrigerated trailer, railcar, shipping container and/or box truck using a plurality of such glass-reinforced thermoplastic interior wall panels. That unit will exhibit greater foam adhesion within said interior wall panels, resulting in less potential damage from container packers and/or during packaging transport. And, due to this increased foam adhesion, such units will have reduced repair/replacement costs and a prolonged useful life.

(50) Applicant believes his improvement fully exploits the revolutionary loop fabric that his method employs. That looped design is not the same typical Velcro underlayment nor even one half of what makes up standard Velcro tape, i.e. the hook OR the partnering loop side. The latter's loops are much smaller and merely intended to coordinate (i.e. mesh) with the hooks of the other material half. It would not be possible, nor practical, to incorporate a full or half portion of typical Velcro tape for achieving the desired adhesion levels observed with the present invention.

(51) The aforementioned loops may be standard/uniform or continuous in relative height to the interwoven base as per FIG. 7A. Alternately, another embodiment would address improvements using loops of variable heights, such as the short, medium and tall loop heights 118a, 118b and 118c for product 110 in accompanying FIG. 7B.

(52) This invention improves the performance of reinforced and non-reinforced panels used for interiors of refrigerated transportation equipment. Admittedly, surface treatments are used all the time for improving adhesion with glues, etc., but this new dimensional loop is truly novel in its unique improvements in this field of use.

(53) Two representative sizes of fully looped materials, made for Applicant by Apex Mills, were manufactured for size comparison purposes. The first was designated RH87 loop material (as seen below):

(54) TABLE-US-00001 STYLE CONTENT: RH87 TEST METHOD 100% POLYESTER ASTM D629 WEIGHT (oz/sq yd): .sup.5.3 +/ 10% ASTM D3776 WALES (width)/inch: 9 +/ 1 ASTM D3887 COURSES (length)/inch: 27 +/ 3 ASTM D3887 INSTRON BALL BURST MIN 75 ASTM D3787 (lbf): MULLEN BURST: N/A ASTM D3786 THICKNESS (inch): 0.18 +/ 0.02 ASTM D1777 TENSILE (LENGTH) N/A ASTM D5034 (WIDTH) N/A ASTM D5034 AT BASE 117 Loops/sq inch +/ 12 Loops Loop height: .sup.6 mm +/ 0.6 mm Loop height: .sup.4 mm +/ 0.4 mm

(55) For a smaller, more compact style of fabric backing, a second scale of substrate was made and tested. Called RJ30, its particulars are as follows:

(56) TABLE-US-00002 STYLE CONTENT: RJ30 TEST METHOD 100% POLYESTER ASTM D629 WEIGHT (oz/sq yd): .sup.4.3 +/ 10% ASTM D3776 WALES (width)/inch: 9 +/ 1 ASTM D3887 COURSES (length)/inch: 27 +/ 3 ASTM D3887 INSTRON BALL BURST MIN 75 ASTM D3787 (lbf): MULLEN BURST: N/A ASTM D3786 THICKNESS (inch): 0.11 +/ 0.011 ASTM D1777 TENSILE (LENGTH) N/A ASTM D5034 (WIDTH) N/A ASTM D5034 AT BASE 63 Loops/sq inch +/ 6.5 Loops Loop height: .sup.5 mm +/ 0.5 mm Loop height: .sup.3 mm +/ 0.3 mm

(57) RH87 and RJ30 are both warp knitted fabrics utilizing a unique construction where 2 multifilament yarn systems form the substrate and a 3.sup.rd heavy gauge monofilament yarn system is anchored on 1 needle and cast off on the alternate needle to form a loop on one side of the fabric while leaving the alternate side of the fabric smooth. Both RJ30 and RH87 are made with 100% Polyester but other yarn types can be substituted therefor.

(58) FIGS. 3 through 6 show other relevant material modifications prior to the parent application AND the present invention. FIG. 3 shows looped layers L onto one another in a typical fabric material. FIG. 4 shows a prior art substrate S from which a single strand of line is embedded from only the adjoining base elements B. FIG. 5 shows a prior art scrim section with its non-woven mat M beneath composite sheet C, similar to the main disclosure of Applicant's U.S. Pat. No. 6,743,742. And FIG. 6 is a modified variation of FIG. 5 with an intentionally roughed up outer fibrous layer O which still does not achieve the bond adhesion levels observed with the present invention.

(59) FIGS. 7 and 7A show one preferred embodiment of interior wall panel 10 made according to the parent invention. The exterior, metal wall to that panel is indicated with a TM designation and its innermost wall panel interior with a TI designation.

(60) Said wall panel 10 has a base material 12, into which is sewn a special looped fabric backing, generally 14, consisting of an underlying substrate layer 16 from which a plurality of polymer loops 18 are interwoven and outwardly extend. The latter loops are encased in an outer foam layer 20 for subsequent lamination to form the wall panel proper. Such loops are necessary and critical for integration into the base for making an improved GRTP product hereby.

(61) FIG. 7B shows an alternate embodiment of wall panel 110, with its own fabric backing 114, and corresponding substrate layer 116 from which three representative heights of variably sized loops, 118a, 118b and 118c are interwoven, and then combed or brushed upward to stand at attention prior to being foamed about.

(62) FIGS. 7C and D show a second alternate embodiment of wall panel 210, with its own fabric backing 214, and corresponding substrate layer 216 from which one representative height of loop 218 is interwoven but with purposeful loop gaps added (either randomly as shown, or in a preset pattern) in the horizontal direction GH, vertical direction GV or both. Though shown much smaller for ease of illustration purposes, a typical loop gap, either horizontal or vertical, may be as much as 12 inches thick, or range from about 1 to 10 inches, more preferably about 3 to 5 inches high (for horizontally extending spaces), or wide (for vertical spaces).

(63) FIG. 8 is a photograph depicting a forward edge to a representative section of the base material from FIGS. 7 and 7A with its rows of interwoven fabric backing attached thereto and its plurality of consistently-sized loops 18 extending upwardly therefrom . . . all before encasement in the foam to make the improved interior wall panel of the parent invention.

(64) FIG. 9 shows an underside of substrate layer 16 (lined) from which the respective rows of loops 18 (unlined, for better illustration) are interwoven. Note how all of the loops tie into the base or weave of substrate layer 16. That base is necessary for embedding into the laminate product: the base sticks to the trailer backing interior TI while the loops of that product stick firmly into the foam injected between the interior TI and metal exterior TM.

(65) FIG. 10 shows a close up view of one representative row of loops 18 with a single braid of the substrate layer 16 wrapped thereabout consistently lined like the two components in preceding FIG. 9.

(66) Finally, FIG. 11 is a representative trailer product with an exterior metal TM surface, showing in cutaway to expose one of its interior walls TI made using the panel improvements 10 of this AND the parent invention.

(67) The primary focus of this invention is to replace full sheets of loop material with sheets having intentionally spaced, or gapped, sections. In other words, this invention uses sheets with either much smaller (or shorter) loops or no loops whatsoever . . . in certain rows (horizontal, vertical, diagonal, or even more random) for improving the adhesion of foam to these spaced/gap sections of loop sheets.

(68) Further advantages of this alternative to sheets that are fully looped, i.e., having repeated rows of loops {in either the same height or in varying heights) across the whole face (i.e., surface area) of said sheets prior to foaming, are both cost and ease of manufacture. In other words, a purposefully gapped section of loop material would be more forgiving and lead to fewer rejections in manufacture/assembly of panels therewith.

(69) Having described the presently preferred embodiments, it is to be understood that this invention may otherwise be covered by the scope of the provisionally filed claims that follow.