Breast pad made with supercritical fluid foam and BRA cups incorporating same

Abstract

A breast pad (650, 750, 850, 950, 1050) has a concave inner face (652, 752, 852, 952, 1052) and a convex outer face (654, 754, 854, 954, 1054) and an SCF foam layer (650, 750b, 850a, 850b, 950a, 1050a). The SCF foam layer is a foam made by a supercritical fluid foaming process. A method of manufacturing a breast pad includes forming an SCF foam piece by way of a supercritical fluid foaming process and forming a breast pad using the SCF foam piece.

Description

BREAST PAD MADE WITH SUPERCRITICAL FLUID FOAM AND BRA CUPSINCORPORATING SAMEFIELD

[0001] The present disclosure relates to breast pads for use in lingerie, sports bras and other sports apparel, and swimwear.BACKGROUND

[0002] Numerous attempts have been made to make components of brassieres and / or swimwear that are recyclable. Often, these efforts result in breast pads that are less than desirable; they are not breathable, are too stiff or not supportive enough, do not have a good hand-feel, are too difficult to manufacture and / or mold to a desired shape, or are not easily recyclable.

[0003] Some efforts to form a recyclable breast pad have focused on the traditional process of crosslinking precursor chemicals during the foaming process. This process includes injection molding a breast pad, stabilizing the molded article, cleaning / washing and then drying the foam, and then ultraviolet treatment of the article. Crosslinking the chemicals in the foam makes them very difficult to recycle.SUMMARY

[0004] This Summary is provided to introduce a selection of concepts that are further described below in the Detailed Description. This Summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in limiting the scope of the claimed subject matter.

[0005] The present inventors realized that the above-noted problems with attempts to create a recyclable breast pad can be overcome by using supercritical fluid foaming to form the breast pad, in combination with a careful selection of the raw material to be foamed. Further, the inventors have realized that supercritical fluid foaming can be used to make pads that are more desirable in terms of the qualities noted hereinabove, even if those pads are not recyclable.

[0006] One example of the present disclosure is of a breast pad comprising a concave inner face and a convex outer face and an SCF foam layer comprising a foam made by a supercritical fluid foaming process.

[0007] According to some aspects, the foam is made from a polymer selected from one of the following: ethylene-vinyl acetate (EVA), styrene-ethylene-butylene-styrene (SEBS), polyamide (PA), thermoplastic polyurethane (TPU), thermoplastic polyester elastomer (TPEE), or ethylenevinyl acetate and styrene-ethylene-butylene-styrene (EVA + SEBS).

[0008] According to some aspects, the SCF foam layer is made by injection molding the polymer mixed with a supercritical fluid into a mold having a concave female part and a convex male part to form a 3D cup.

[0009] According to some aspects, the SCF foam layer is made by injection molding the polymer mixed with a supercritical fluid into a mold having a planar cavity to form a flat sheet.

[0010] According to some aspects, the breast pad further comprises an inner layer of foam defining the concave inner face and an outer layer of foam defining the convex outer face. The SCF foam layer is sandwiched between the inner layer of foam and the outer layer of foam.

[0011] According to some aspects, the breast pad further comprises an outer layer of foam defining the convex outer face, and the SCF foam layer defines the concave inner face.

[0012] According to some aspects, the breast pad further comprises a spacer fabric defining the convex outer face, and the SCF foam layer defines the concave inner face.

[0013] According to some aspects, the SCF foam layer defines both the convex outer face and the concave inner face.

[0014] Another example of the present disclosure is of a method of manufacturing a breast pad. The method comprises forming an SCF foam piece by way of a supercritical fluid foaming process and forming a breast pad using the SCF foam piece. The breast pad has a concave inner face and a convex outer face.

[0015] According to some aspects, forming the SCF foam piece comprises mixing a polymer raw material with a supercritical fluid. The polymer raw material is selected from one of the following: ethylene-vinyl acetate (EVA), styrene-ethylene-butylene-styrene (SEBS), polyamide (PA), thermoplastic polyurethane (TPU), thermoplastic polyester elastomer (TPEE), or ethylenevinyl acetate and styrene-ethylene-butylene-styrene (EVA + SEBS).

[0016] According to some aspects, forming the SCF foam piece comprises injecting the mixed polymer raw material and supercritical fluid into a mold having a concave female part and a convex male part to form a 3D cup.

[0017] According to some aspects, forming the SCF foam piece comprises injecting the mixed polymer raw material and supercritical fluid into a first mold having a planar cavity to form a flat sheet.

[0018] According to some aspects, the method further comprises providing an inner layer of foam and an outer layer of foam; sandwiching the SCF foam piece between the inner layer of foam and the outer layer of foam; placing the inner layer of foam, outer layer of foam, and SCF foam piece into a second mold; and molding the inner layer of foam, outer layer of foam, and SCF foam piece into a 3D cup. The inner layer of foam defines the concave inner face and the outer layer of foam defines the convex outer face upon completion of the molding step.

[0019] According to some aspects, the method further comprises providing an outer layer of foam; placing the outer layer of foam and the SCF foam piece into a second mold; and molding the outer layer of foam and the SCF foam piece into a 3D cup. The outer layer of foam defines the convex outer face and the SCF foam piece defines the concave inner face upon completion of the molding step.

[0020] According to some aspects, the method further comprises providing an outer layer of spacer fabric; placing the outer layer of spacer fabric and the SCF foam piece into a second mold; and molding the outer layer of spacer fabric and the SCF foam piece into a 3D cup. The outer layer of spacer fabric defines the convex outer face and the SCF foam piece defines the concave inner face upon completion of the molding step.

[0021] According to some aspects, the SCF foam piece defines both the convex outer face and the concave inner face.

[0022] According to some aspects, the SCF foam piece is a first SCF foam piece comprising a first polymer. The method further comprises forming a second SCF foam piece by way of a supercritical fluid foaming process, the second SCF foam piece comprising a second polymer different from the first polymer; placing the first SCF foam piece adjacent to the second SCF foam piece in a mold; and molding the first and second SCF foam pieces together into a 3D cup.

[0023] According to some aspects, the method further comprises setting a temperature of a female half of the mold to a first temperature and setting a temperature of a male half of the moldto a second temperature different from the first temperature during the step of molding. According to some aspects, the first and second temperatures are both between 90 °C and 160 °C. According to some aspects, the first temperature is between 130°C and 160°C, and the second temperature is between 90°C and 120°C.

[0024] According to some aspects, the method further comprises comprising removing a skin from the SCF foam piece prior to forming the breast pad using the SCF foam piece.BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present disclosure is described with reference to the following Figures. The same numbers are used throughout the Figures to reference like features and like components.

[0026] FIG. 1 illustrates an assembly for forming a supercritical foam in the form of a sheet.

[0027] FIG. 2 illustrates an assembly for forming a supercritical foam in the form of a 3D cup-shaped piece.

[0028] FIG. 3 is a method for forming a supercritical foam sheet, processing the foam sheet, and molding the foam sheet into a 3D cup shape.

[0029] FIG. 4 is a method for forming a supercritical foam 3D cup and processing the foam 3D cup.

[0030] FIG. 5 shows a breast pad made according to the method of FIG. 3 or FIG. 4.

[0031] FIG. 6 is a cross section of a bra cup according to one example of the present disclosure, the bra cup comprising an SCF foam layer.

[0032] FIG. 7 is a cross section of a bra cup according to another example of the present disclosure, the bra cup comprising an SCF foam cookie sandwiched between two traditional foam layers.

[0033] FIG. 8 is a cross section of a bra cup according to another example of the present disclosure, the bra cup comprising two SCF foam layers made using different polymer raw materials.

[0034] FIG. 9 is a cross section of a bra cup according to another example of the present disclosure, the bra cup comprising an inner SCF foam layer and an outer traditional foam layer.

[0035] FIG. 10 is a cross section of a bra cup according to another example of the present disclosure, the bra cup comprising an inner SCF foam layer and an outer spacer fabric layer.

[0036] FIG. 11 is a method for forming a breast pad according to one example of the present disclosure.

[0037] FIG. 12 is a method for forming an SCF foam piece according to one example of the present disclosure.

[0038] FIG. 13 is a method for forming the breast pad shown in FIG. 7.

[0039] FIG. 14 is a method for forming the breast pad shown in FIG. 8.

[0040] FIG. 15 is a method for forming the breast pad shown in FIG. 9.

[0041] FIG. 16 is a method for forming the breast pad shown in FIG. 10.DETAILED DESCRIPTION

[0042] Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items.

[0043] Unless otherwise specified or limited, the phrases “at least one of A, B, and C,” “one or more of A, B, and C,” and the like, are meant to indicate A, or B, or C, or any combination of A, B, and / or C, including combinations with multiple instances of A, B, and / or C. Likewise, unless otherwise specified or limited, the terms “mounted,” “connected,” “linked,” “supported,” and “coupled” and variations thereof are used broadly and encompass both direct and indirect mountings, connections, supports, and couplings. Further, unless otherwise specified or limited, “connected” and “coupled” are not restricted to physical or mechanical connections or couplings.

[0044] As used herein, unless otherwise limited or defined, discussion of particular directions is provided by example only, with regard to particular embodiments or relevant illustrations. For example, discussion of “top,” “bottom,” “front,” “back,” “left,” “right,” “lateral” or “longitudinal” features is generally intended as a description only of the orientation of such features relative to a reference frame of a particular example or illustration.Correspondingly, for example, a “top” feature may sometimes be disposed below a “bottom”feature (and so on), in some arrangements or embodiments. Additionally, use of the words “first,” “second”, “third,” etc. is not intended to connote priority or importance, but merely to distinguish one of several similar elements from another.

[0045] Supercritical fluid (SCF) foaming involves melting a chemical raw material (generally a polymer), mixing the raw material with a supercritical fluid to foam the raw material, and injecting the mixture into a mold. A supercritical fluid is a material that is heated to a state above its critical temperature and pressure, in which the gas and liquid phases are not distinct from one another, but rather coexist. In non-limiting examples, the SCF may be carbon dioxide or nitrogen.

[0046] The chemical raw material used in the SCF foaming process is a thermoplastic polymer. Some suitable thermoplastic polymers are thermoplastic elastomers, such as ethylenevinyl acetate (EVA), styrene-ethylene-butylene-styrene (SEBS), thermoplastic polyester elastomer (TPEE), thermoplastic polyurethane (TPU), or engineered thermoplastic polyurethane (ETPU). Other suitable thermoplastic polymers are polyamides, such as PA 11 (for example, biobased PA 11). Foaming these polymers with SCF creates open cell foams with skin that are recyclable. Combinations of raw materials could also be used in the SCF foaming process, for example, ethylene-vinyl acetate and styrene-ethylene-butylene-styrene (EVA + SEBS), which is not recyclable, but which creates a much softer foam when foamed using a SCF foaming method than when foamed using a traditional crosslinking method. Other suitable thermoplastic polymers that could be used as the raw material include polyethylene, polystyrene (PS), expanded polystyrene (EPS), or expanded polypropylene (EPP). Variants containing biobased components of the above polymers are also contemplated within the scope of the present disclosure.

[0047] As shown in FIG. 1, the polymer raw material can be provided to a barrel 12 of an injection molding machine 10 via a hopper 14. Meanwhile, the supercritical fluid is provided to the barrel 12 via a controllable valve 16. Heating coils 18 heat the barrel 12 and the contents thereof. A screw 20, driven by a motor 22, rotates within the barrel 12 to mix the contents and move them toward an exit nozzle 24 at one end of the barrel 12. The contents are provided from the exit nozzle 24 to a mold 26, where the contents are cooled to create the foam piece. The mold 26 includes a male part 28 and a female part 30. The female part 30 moves in the direction of the arrow A toward and away from the male part 28 to open and close the mold 26. In FIG. 1 , themold 26 is open, with the female part 30 separated from the male part 28. This is the position of the female part 30 when the mold 26 is opened to remove the cooled foam piece. However, the male and female parts 28, 30 of the mold 26 are directly adjacent one another (i.e., the mold is closed) while the contents of the barrel 12 are injected into the mold 26. This causes the foamed material to fill the cavity 32 of the female part 30, as limited by the confines of the cavity 32 and the facing surface of the male part 28.

[0048] In FIG. 1, the cavity 32 in the female part 30 of the mold 26 is planar such that the foam piece that is created will be a flat sheet. The flat sheet can have the outline of a breast pad or can be another shape such as a rectangle, which is later cut to a breast pad shape.

[0049] In contrast, in FIG. 2, the mold 226 is designed to form a foam piece that has the outline, size, and three-dimensional concavity and convexity of a breast pad. In this regard, the mold 226 of FIG. 2 will be referred to as one that creates a “3D cup” or a “3D cup-shaped piece of foam,” although it should be understood that even the flat sheet created by the mold of FIG. 1 is technically three-dimensional in that it has a length, width, and thickness. Therefore, by “3D cup” it is meant that the breast pad has a concave inner face and a convex outer face. The mold of FIG. 2 also includes a male part 228 and a female part 230 with a cavity 232. The cavity 232 in this mold 226 is concave in order to form the convex outer face of the breast pad. The male part 228 includes a convex projecting portion 234 that forms the concave inner face of the breast pad. The breast pad 50, including its concave inner face 52 and convex outer face 54, is shown in FIG. 5.

[0050] The SCF foaming process creates a skin on the foam piece, regardless of whether the mold of FIG. 1 or FIG. 2 is used. The present inventors have realized that removal of the skin from the foam piece is desirable before the foam piece is further processed to form a bra cup, in order to increase breathability, increase softness, and provide a desirable hand-feel.

[0051] As shown in FIG. 3, the injection molding machine 10 and mold 26 of FIG. 1 can be used to carry out a method including the following steps:1. Supercritical fluid foaming of polymer raw material;2. Injection molding flat sheet using mold of FIG. 1 ;3. Removing the skin from the foam sheet;4. Thermal molding of the foam sheet into a 3D cup.

[0052] Steps 1 and 2 are described with respect to FIG. 1. Step 3 may include mechanical means of removing the skin from the foam sheet. Because the foam sheet is flat, the skin can be shaved off. Other mechanical means or chemical means can be used. Regarding step 4, the flat sheet (from which the skin has been removed) can be molded into a 3D cup. The foam sheet can be molded alone as a first molding step, prior to combination of the resulting 3D cup-shaped piece of foam with other layers and a subsequent second molding thereof. Alternatively, the first and only molding step can be done simultaneously with fabric, optional additional foam layers, and adhesive being layered with the SCF foam sheet.

[0053] As shown in FIG. 4, the injection molding machine 10 and mold 226 of FIG. 2 can be used to carry out a method including the following steps:1. Supercritical fluid foaming of polymer raw material;2. Injection molding 3D cup using mold of FIG. 2;3a. Removing the skin from the 3D cup using chemical processing;3b. Removing the skin from the 3D cup using mechanical devices and processes.

[0054] Steps 1 and 2 are described with respect to FIG. 2. Steps 3a and 3b may be alternative methods of removing the skin from the foam, or both types of processes may be used on the same foam article. It may be desirable to use chemical processing to remove the skin from the 3D cup-shaped piece of foam seeing as the mechanical devices required to remove the skin from convex and concave surfaces may be relatively expensive, time-consuming, and / or complex. On the other hand, it may be desirable to use mechanical skin-removal processes for environmental reasons. Note that step 4, thermal molding, is not required, as the piece of foam is already formed / shaped as a 3D cup. However, it may be desirable to mold the 3D cup-shaped foam piece together with fabric, optional additional foam layers, and adhesive to form a finished bra cup.

[0055] Examples of bra cups made using breast pads incorporating one or more foam layers made using SCF will now be described with respect to FIGS. 6-10.

[0056] FIG. 6 shows a cross section of a bra cup 600 comprising a breast pad 650 having a concave inner face 652 and a convex outer face 654. The breast pad 650 is an SCF foam layer that defines both the convex outer face 654 and the concave inner face 652. The concave inner face 652 is covered with an inner fabric liner 656. The convex outer face 654 is covered with an outer fabric liner 658. The breast pad 650, which consists of the SCF foam layer, can be made as a flat sheet according to the process of FIG. 3 or as a 3D cup according to the process of FIG. 4.A molding step conducted in a second mold (i.e., a mold other than the one used for injection molding of the SCF foam layer) can be used to attach the inner fabric liner 656 and the outer fabric liner 658 to the breast pad 650 using adhesive.

[0057] FIG. 7 shows a cross section of a bra cup 700 comprising a breast pad 750 having a concave inner face 752 and a convex outer face 754. The breast pad 750 comprises an inner foam layer 750a that defines the concave inner face 752 and an outer foam layer 750c that defines the convex outer surface 754. The concave inner face 752 is covered with an inner fabric liner 756. The convex outer face 754 is covered with an outer fabric liner 758. An SCF foam piece 750b (sometimes referred to as a “cookie”) is sandwiched between the inner foam layer 750a and the outer foam layer 750c. The SCF foam piece 750b can be made as a flat sheet according to the process of FIG. 3 and thereafter shaved into the desired shape, or the SCF foam piece 750b can be made as a 3D piece directly according to the process of FIG. 4. The inner and outer foam layers 750a, 750c can be polyurethane (PU) foam made using a conventional foaming process requiring crosslinking of the PU raw materials. A molding step can be used to attach the inner fabric liner 756 and the outer fabric liner 758 to the inner foam layer 750a and the outer foam layer 750c, respectively, while also attaching the SCF foam piece 750b to the inner and outer foam layers 750a, 750c and molding all the layers into a 3D cup. Optionally, the foam layers 750a, 750c can each be molded separately prior to being molded together with the additional layers of the bra cup 700. This may be beneficial because molding of traditional crosslinked PU foam into a 3D cup shape generally requires higher molding temperatures and longer molding times than molding of an SCF foam into a 3D cup shape. Details of the molding process will be described further herein below with respect to FIG. 13. The traditional PU foam layers may provide a desired level of support to the bra cup 700 that the SCF foam piece alone is unable to provide, while the SCF foam piece may be a thick piece of foam that provides lift and volume to the bra cup 700. The thick SCF foam piece 750b may be de-bondable from the traditional PU foam layers and thereafter recycled, rendering a high percentage of the foam material recyclable.

[0058] FIG. 8 shows a cross section of a bra cup 800 comprising a breast pad 850 having a concave inner face 852 and a convex outer face 854. The breast pad 850 comprises a first SCF foam layer 850a that defines the concave inner face 852 and a second SCF foam layer 850b that defines the convex outer face 854. The concave inner face 852 is covered with an inner fabric liner 856. The convex outer face 854 is covered with an outer fabric liner 858. Each of the twoSCF foam layers 850a, 850b can be made as flat sheets according to the process of FIG. 3. In some examples, the polymer used to make the first SCF foam layer 850a is different from the polymer used to make the second SCF foam layer 850b. A molding step can be used to attach the inner fabric liner 856 and the outer fabric liner 858 to the first SCF foam layer 850a and second SCF foam layer 850b, respectively, while also attaching the first and second SCF foam layers 850a, 850b to one another and molding them into a 3D cup. Details of the molding process will be described further herein below with respect to FIG. 14.

[0059] FIG. 9 shows a cross section of a bra cup 900 comprising a breast pad 950 having a concave inner face 952 and a convex outer face 954. The breast pad 950 comprises an SCF foam layer 950a that defines the concave inner face 952 and a foam layer 950b that defines the convex outer face 954. The concave inner face 952 is covered with an inner fabric liner 956. The convex outer face 954 is covered with an outer fabric liner 958. The SCF foam layer 950a can be made as a flat sheet according to the process of FIG. 3. The foam layer 950b can be a polyurethane (PU) foam sheet made using a conventional foaming process requiring crosslinking of the PU raw materials. A molding step can be used to attach the inner fabric liner 956 and the outer fabric liner 958 to the SCF foam layer 950a and the foam layer 950b, respectively, while also attaching the SCF foam layer 950a to the foam layer 950b and molding them into a 3D cup. Optionally, the foam layer 950b can be molded separately prior to being molded together with the additional layers of the bra cup 900. This may be beneficial because molding of traditional crosslinked PU foam into a 3D cup shape generally requires higher molding temperatures and longer molding times than molding of an SCF foam into a 3D cup shape. Details of the molding process will be described further herein below with respect to FIG. 15. Note that while the SCF foam layer is shown as the inner layer in the example of FIG. 9 and the traditional PU foam layer is the outer layer, the two layers could be reversed. The traditional PU foam layer may provide a desired level of support to the bra cup 900 that the SCF foam layer alone is unable to provide.

[0060] FIG. 10 shows a cross section of a bra cup 1000 comprising a breast pad 1050 having a concave inner face 1052 and a convex outer face 1054. The breast pad 1050 comprises an SCF foam layer 1050a that defines the concave inner face 1052 and a spacer fabric layer 1050b that defines the convex outer face 1054. The concave inner face 1052 is covered with an inner fabric liner 1056. The convex outer face 1054 is not covered with a fabric liner. Rather, the outerfacing surface of the spacer fabric layer 1050b is the visible outer surface of the bra cup 1000. Inanother example, the convex outer face 1054 may be covered with an outer fabric liner. The SCF foam layer 1050a can be made as a flat sheet according to the process of FIG. 3. The spacer fabric layer 1050b can be any known three-dimensional fabric that has a first face layer, a second face layer, and a pile / connecting layer between the first face layer and the second face layer. A molding step can be used to attach the inner fabric liner 1056 to the SCF foam layer 1050a and the spacer fabric layer 1050b, respectively, while also attaching the SCF foam layer 1050a to the spacer fabric layer 1050b and molding them into a 3D cup. Details of the molding process will be described further herein below with respect to FIG. 16. The spacer fabric layer may provide a desired level of support to the bra cup 1000 that the SCF foam layer alone is unable to provide, while also providing a jelly feel to the bra cup 1000 that makes it feel like real breast tissue. In some examples, a cookie in the form of an additional SCF foam piece (not shown) may be provided between the spacer fabric layer 1050b and the SCF foam layer 1050a, which cookie provides a push-up effect to the wearer’s breasts.

[0061] Methods for manufacturing the breast pads and bra cups of FIGS. 6-10 will now be described with respect to FIGS. 11-16.

[0062] Referring to FIG. 11, in general, a method of manufacturing a breast pad comprises forming an SCF foam piece by way of a supercritical fluid foaming process, as shown at SI. The method optionally comprises removing a skin from the SCF foam piece, as shown at S2. The method also comprises forming a breast pad using the SCF foam piece, as shown at S3. The molding step of S3 results in the breast pad having a concave inner face and a convex outer face.

[0063] FIG. 12 shows more details of SI of FIG. 11. The step SI of forming an SCF foam piece by way of a supercritical fluid foaming process comprises mixing a polymer raw material with a supercritical fluid, as shown at SI 1, and injecting the mixed polymer raw material and supercritical fluid into a mold, as shown at SI 2. The polymer raw material is selected from one of the following: ethylene-vinyl acetate (EVA), styrene-ethylene-butylene-styrene (SEBS), polyamide (PA), thermoplastic polyurethane (TPU), thermoplastic polyester elastomer (TPEE), or ethylene-vinyl acetate and styrene-ethylene-butylene-styrene (EVA + SEBS). Step S12 may include injecting the mixed polymer raw material and supercritical fluid into a mold having a concave female part and a convex male part to form a 3D cup, as discussed hereinabove with respect to FIG. 2. Step S12 may alternatively include injecting the mixed polymer raw materialand supercritical fluid into a first mold having a planar cavity to form a flat sheet, as discussed hereinabove with respect to FIG. 1.

[0064] In the example in which step S12 comprises injecting the mixed polymer raw material and supercritical fluid into a mold having a concave female part and a convex male part to form a 3D cup, the SCF foam piece defines both the convex outer face and the concave inner face of the breast cup. An example of a bra cup 600 formed using an optionally 3D-molded SCF foam piece is shown in FIG. 6. As noted above, the 3D-molded SCF foam piece can be molded in further molding steps, if desired.

[0065] In examples in which step S12 comprises injecting the mixed polymer raw material and supercritical fluid into a first mold having a planar cavity to form a flat sheet, the flat sheet may undergo further molding in a second mold with other layers (e.g., additional SCF foam pieces, traditional crosslinked PU foam, various fabrics, and adhesive) to form a bra cup.

[0066] For example, to form the bra cup 700 of FIG. 7, step S3 of FIG. 11 may include the steps shown in FIG. 13. At step S31, the method includes providing an inner layer of foam 750a and an outer layer of foam 750c, both of which may be traditional crosslinked PU foams. At step S32, the method optionally includes molding the inner layer of foam 750a into a 3D cup shape. At step S33, the method optionally includes molding the outer layer of foam 750c into a 3D cup shape. As noted hereinabove, when the inner and outer layers of foam are conventionally foamed PU, they may require molding at higher temperatures for a longer period of time than a piece of foam made using an SCF foaming process. Therefore, the inner and outer layers of foam 750a, 750c may be separately molded to shape prior to molding with the SCF foam piece 750b. At step S34, the method includes sandwiching the SCF foam piece 750b between the inner layer of foam 750a and the outer layer of foam 750c, which were optionally pre-molded into shape as noted above. At step S35, the method includes placing the inner layer of foam 750a, outer layer of foam 750c, and SCF foam piece 750b into a second mold (i.e., a mold other than the mold used for injection molding of the SCF foam piece). At step S36, the method includes molding the inner layer of foam 750a, outer layer of foam 750c, and SCF foam piece 750b into a 3D cup. In the resulting bra cup 700 shown in FIG. 7, the inner layer of foam 750a defines the concave inner face 752 and the outer layer of foam 750c defines the convex outer face 754 upon completion of the molding step.

[0067] As another example, to form the bra cup 800 of FIG. 8, Step S3 of FIG. 11 may include the steps shown in FIG. 14. At S311, the method includes forming a first SCF foam piece 850a comprising a first polymer by way of a supercritical fluid foaming process. At S312, the method includes forming a second SCF foam piece 850b comprising a second polymer by way of a supercritical fluid foaming process. According to advantageous embodiments, the second polymer is different from the first polymer. At S313, the method includes placing the first SCF foam piece 850a adjacent to the second SCF foam piece 850b in a mold other than the mold used for injection molding of the SCF foam pieces. At S314, the method optionally includes setting a temperature of a female half of the mold to a first temperature and setting a temperature of a male half of the mold to a second temperature different from the first temperature. At S315, the method includes molding the first and second SCF foam pieces 850a, 850b together into a 3D cup. In the resulting bra cup 800 shown in FIG. 8, the first SCF foam piece 850a defines the concave inner face 852 and the second SCF foam piece 850b defines the convex outer face 854 upon completion of the molding step.

[0068] As noted, the male and female halves of the mold may be set to different temperatures during step S314. In advantageous embodiments, the first and second temperatures are both between 90°C and 160°C. This is significantly lower than the temperature of 190°C required for molding of traditional crosslinked PU foam into a 3D cup shape. In a specific example, the first temperature is between 130°C and 160°C, and the second temperature is between 90°C and 120°C. A temperature of between 130°C and 160°C may be appropriate for the mold half that contacts an SCF foam piece made of TPU, TPEE, or higher density SEBS. A temperature of between 90°C and 120°C may be appropriate for the mold half that contacts an SCF foam piece made of lower density SEBS. In one example, a bra cup 800 is made using lower density SEBS as the inner SCF foam layer 850a, and thus the male mold half (which forms the concave inner face 852) is set to a temperature of between 90°C and 120°C. In the same example, the outer SCF foam layer 850b is made using TPU, TPEE, or higher density SEBS, and thus the female mold half (which forms the convex outer face 854) is set to a temperature of between 130°C and 160°C. The lower density SEBS provides good memory function and handfeel and therefore is suitable as the layer of foam that is closest to the wearer’s breast tissue. Meanwhile, the TPU, TPEE, or higher density SEBS provide more support to the cup than the lower density SEBS is able to provide alone. In one example, the higher density SEBS has a density of 0.18 g / cm3,while the lower-density SEBS has a density of 0.12 g / cm3. Although the examples provided hereinabove discuss molding the SEBS materials at different temperatures and / or for different lengths of time, in other examples, the higher-density and lower-density SEBS can be molded together at the same temperature for the same length of time.

[0069] As another example, to form the bra cup 900 of FIG. 9, step S3 of FIG. 11 may include the steps shown in FIG. 15. At step S321, the method includes providing an outer layer of foam 950b, which may be a traditional crosslinked PU foam. At step S322, the method optionally includes molding the outer layer of foam 950b into a 3D cup shape. As noted hereinabove, when the layer of foam is conventionally foamed PU, it may may require molding at higher temperatures for a longer period of time than a piece of foam made using the SCF foaming process. Therefore, the outer layer of foam 950b may be separately molded to shape prior to molding with the SCF foam piece 950a. The method includes placing the outer layer of foam 950b and the SCF foam piece 950a into a second mold (i.e., a mold other than the mold used for injection molding of the SCF foam piece) as shown at S323. At S324, the method includes molding the outer layer of foam 950b and the SCF foam piece 950a into a 3D cup. In the resulting bra cup 900 shown in FIG. 9, the outer layer of foam 950b defines the convex outer face 954 and the SCF foam piece 950a defines the concave inner face 952 upon completion of the molding step.

[0070] As another example, to form the bra cup 1000 of FIG. 10, Step S3 of FIG. 11 may include the steps shown in FIG. 16. The method includes providing an outer layer of spacer fabric 1050b, as shown at S331. Optionally, the spacer fabric 1050b may be molded separately without the SCF foam piece 1050a before proceeding to step S332, which molding step may include molding the spacer fabric 1050b at a higher temperature than that used in the subsequent step of molding the spacer fabric 1050b and the SCF foam piece 1050a together. At S332, the method includes placing the outer layer of spacer fabric 1050b and the SCF foam piece 1050a into a second mold (i.e., a mold other than the mold used for injection molding of the SCF foam piece). The optional SCF foam cookie is also placed in the mold in step S332, between the spacer fabric 1050b and the SCF foam piece 1050a. At S333, the method includes molding the outer layer of spacer fabric 1050b and the SCF foam piece 1050a (and the optional SCF foam cookie) into a 3D cup. In the resulting bra cup 1000 shown in FIG. 10, the outer layer of spacerfabric 1050b defines the convex outer face 1054 and the SCF foam piece 1050a defines the concave inner face 1052 upon completion of the molding step.

[0071] Therefore, the methods described hereinabove can be used to manufacture a breast pad comprising a concave inner face and a convex outer face and an SCF foam layer comprising a foam made by a supercritical fluid foaming process. In some examples, the foam is made from a polymer selected from one of the following: ethylene-vinyl acetate (EVA), styrene-ethylene- butylene-styrene (SEBS), polyamide (PA), thermoplastic polyurethane (TPU), thermoplastic polyester elastomer (TPEE), or ethylene-vinyl acetate and styrene-ethylene-butylene-styrene (EVA + SEBS).

[0072] In some examples, the SCF foam layer is made by injection molding the polymer mixed with a supercritical fluid into a mold having a concave female part and a convex male part to form a 3D cup.

[0073] In other examples, the SCF foam layer is made by injection molding the polymer mixed with a supercritical fluid into a mold having a planar cavity to form a flat sheet.

[0074] In the example of FIG. 6, the SCF foam layer 650 defines both the convex outer face 654 and the concave inner face 652.

[0075] In the example of FIG. 7, the breast pad 700 further comprises an inner layer of foam 750a defining the concave inner face 752 and an outer layer of foam 750c defining the convex outer face 754, wherein the SCF foam layer 750b is sandwiched between the inner layer of foam 750a and the outer layer of foam 750c.

[0076] In the example of FIG. 8, the breast pad 800 has two SCF foam layers. The first SCF foam layer 850a defines the concave inner face 852 and the second SCF foam layer 850b defines the convex outer face 854.

[0077] In the example of FIG. 9, the breast pad 900 further comprises an outer layer of foam 950b defining the convex outer face 954, and the SCF foam layer 950a defines the concave inner face 952.

[0078] In the example of FIG. 10, the breast pad 1000 further comprises a spacer fabric 1050b defining the convex outer face 1054, and the SCF foam layer 1050a defines the concave inner face 1052.

[0079] Other variations are contemplated within the scope of the present disclosure, such as a bra cup made with an inner SCF foam layer, an outer SCF foam layer, and an SCF foam cookiesandwiched between the inner and outer SCF foam layers. The SCF foams can each be made from different polymers, or two or more of the layers can be made from the same polymer. Embodiments including an SCF foam inner layer, a traditional foam outer layer, and an SCF foam cookie between the inner and outer layers are also contemplated. Moreover, it should be noted that the traditional foam could be made of materials other than polyurethane.

[0080] As noted, some of the breast pads produced according to the processes described herein are recyclable. Because the SCF foaming process does not require crosslinking the chemicals in the foam material, the foam can be heated / pelletized and thereby returned to a raw material form for re-use. With the exception of EVA + SEBS, the raw materials discussed herein are recyclable. Further, the supercritical fluids themselves are also recyclable. Supercritical fluid that boils off as gas can be captured during the injection molding process and re-used.

[0081] As noted, PA 11 is one of the recyclable raw materials that can be used to produce the foam breast pad. In one example, biobased PA 11 can be used to form a bra that is 100% biobased PA 11 and that is recyclable. Each of the trim, foam, and fabric, and optionally the glue, used to make the bra can be made of 100% biobased PA 11. For example, for a breast pad that is made of foam adhered to fabric with glue, each of the foam, glue, and fabric can be made of PA 11 such that the breast pad can be recycled as a single unit. This allows the entire breast pad to be recycled without having to be deconstructed beforehand. Components of the remainder of the bra, such as any underwires, hooks and eyes, clips / clasps, rings, and sliders, may need to be made from different materials, but these are relatively easy to remove compared to trying to separate fabric from foam (e.g., as would otherwise need to be done to recycle the bra cup). In some examples, the bra may be a pullover wireless bra that does not include any of these non-PA components, and therefore the entire bra as a single, whole unit may be recyclable. In another example, the foam is thermoplastic foam (such as PA 11) and the fabric is made of a different type of material (which may be recyclable or non-recyclable). In such an example, the glue that holds the foam and the fabric together is de -bondable, such as by heat and / or chemical treatment, such that the foam can be recycled separately from the fabric after the two components are debonded from one another.

[0082] In other examples, nylons such as PA 56 (partially biobased, with 47-100% renewable carbon content), PA 410, PA 510, PA 610, or PA 1010 may instead be used.

[0083] The base used to make the biobased raw material that is to be foamed or formed into yarn can be corn starch, sugarcane, vegetable fat, or castor oil.

[0084] In the above description, certain terms have been used for brevity, clarity, and understanding. No unnecessary limitations are to be inferred therefrom beyond the requirement of the prior art because such terms are used for descriptive purposes and are intended to be broadly construed. The order of method steps or decisions shown in the Figures and described herein are not limiting on the appended claims unless logic would dictate otherwise. It should be understood that the decisions and steps can be undertaken in any logical order and / or simultaneously. The different systems and methods described herein may be used alone or in combination with other systems and methods. It is to be expected that various equivalents, alternatives and modifications are possible within the scope of the appended claims.

Claims

CEAIMSWhat is claimed is:

1. A breast pad comprising: a concave inner face and a convex outer face; and an SCF foam layer comprising a foam made by a supercritical fluid foaming process.

2. The breast pad of claim 1 , wherein the foam is made from a polymer selected from one of the following: ethylene-vinyl acetate (EVA), styrene-ethylene-butylene-styrene (SEBS), polyamide (PA), thermoplastic polyurethane (TPU), thermoplastic polyester elastomer (TPEE), or ethylene-vinyl acetate and styrene-ethylene-butylene-styrene (EVA + SEBS).

3. The breast pad of claim 2, wherein the SCF foam layer is made by injection molding the polymer mixed with a supercritical fluid into a mold having a concave female part and a convex male part to form a 3D cup.

4. The breast pad of claim 2, wherein the SCF foam layer is made by injection molding the polymer mixed with a supercritical fluid into a mold having a planar cavity to form a flat sheet.

5. The breast pad of claim 1, further comprising an inner layer of foam defining the concave inner face and an outer layer of foam defining the convex outer face, wherein the SCF foam layer is sandwiched between the inner layer of foam and the outer layer of foam.

6. The breast pad of claim 1 , further comprising an outer layer of foam defining the convex outer face, wherein the SCF foam layer defines the concave inner face.

7. The breast pad of claim 1, further comprising a spacer fabric defining the convex outer face, wherein the SCF foam layer defines the concave inner face.

8. The breast pad of claim 1, wherein the SCF foam layer defines both the convex outer face and the concave inner face.

9. A method of manufacturing a breast pad, the method comprising: forming an SCF foam piece by way of a supercritical fluid foaming process; and forming a breast pad using the SCF foam piece, the breast pad having a concave inner face and a convex outer face.

10. The method of claim 9, wherein forming the SCF foam piece comprises mixing a polymer raw material with a supercritical fluid; wherein the polymer raw material is selected from one of the following: ethylene-vinyl acetate (EVA), styrene-ethylene-butylene-styrene (SEBS), polyamide (PA), thermoplastic polyurethane (TPU), thermoplastic polyester elastomer (TPEE), or ethylene-vinyl acetate and styrene-ethylene-butylene-styrene (EVA + SEBS).

11. The method of claim 10, wherein forming the SCF foam piece comprises injecting the mixed polymer raw material and supercritical fluid into a mold having a concave female part and a convex male part to form a 3D cup.

12. The method of claim 10, wherein forming the SCF foam piece comprises injecting the mixed polymer raw material and supercritical fluid into a first mold having a planar cavity to form a flat sheet.

13. The method of claim 12, further comprising: providing an inner layer of foam and an outer layer of foam; sandwiching the SCF foam piece between the inner layer of foam and the outer layer of foam; placing the inner layer of foam, outer layer of foam, and SCF foam piece into a second mold; and molding the inner layer of foam, outer layer of foam, and SCF foam piece into a 3D cup; wherein the inner layer of foam defines the concave inner face and the outer layer of foam defines the convex outer face upon completion of the molding step.

14. The method claim 12, further comprising: providing an outer layer of foam; placing the outer layer of foam and the SCF foam piece into a second mold; and molding the outer layer of foam and the SCF foam piece into a 3D cup; wherein the outer layer of foam defines the convex outer face and the SCF foam piece defines the concave inner face upon completion of the molding step.

15. The method claim 12, further comprising: providing an outer layer of spacer fabric; placing the outer layer of spacer fabric and the SCF foam piece into a second mold; and molding the outer layer of spacer fabric and the SCF foam piece into a 3D cup; wherein the outer layer of spacer fabric defines the convex outer face and the SCF foam piece defines the concave inner face upon completion of the molding step.

16. The method of claim 9, wherein the SCF foam piece defines both the convex outer face and the concave inner face.

17. The method of claim 9, wherein the SCF foam piece is a first SCF foam piece comprising a first polymer, and further comprising: forming a second SCF foam piece by way of a supercritical fluid foaming process, the second SCF foam piece comprising a second polymer different from the first polymer; placing the first SCF foam piece adjacent to the second SCF foam piece in a mold; and molding the first and second SCF foam pieces together into a 3D cup.

18. The method of claim 17, further comprising setting a temperature of a female half of the mold to a first temperature and setting a temperature of a male half of the mold to a second temperature different from the first temperature during the step of molding.

19. The method of claim 18, wherein the first and second temperatures are both between90°C and 160°C.

20. The method of claim 19, wherein the first temperature is between 130°C and 160°C, and the second temperature is between 90°C and 120°C.

21. The method of claim 9, further comprising removing a skin from the SCF foam piece prior to forming the breast pad using the SCF foam piece.

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