EP4626668A2

EP4626668A2 - Molded polyester pad and process for producing the same

Info

Publication number: EP4626668A2
Application number: EP24713783.9A
Authority: EP
Inventors: Eric Kozlowski; Brian Bartkowiak
Original assignee: Magna Seating Inc
Current assignee: Magna Seating Inc
Priority date: 2023-02-13
Filing date: 2024-02-13
Publication date: 2025-10-08
Also published as: WO2024173295A3; WO2024173295A2

Abstract

A molded base pad for an automotive seat assembly includes a polyester batting blocker having a random web of bulk polyester fibers and melt polyester fibers which has been compressed and heated to form a 3-dimensional shaped base pad. At least a portion of the melt polyester fibers have melted and bonded with at least a portion of the bulk polyester fibers. The molded base pad includes an outer portion surrounding an inner portion with the inner portion having an inner firmness, the outer portion having an outer firmness, and the inner firmness is different than the outer firmness.

Description

MOLDED POLYESTER PAD AND PROCESS FOR PRODUCING THE SAME

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Provisional Application 63/445,072, filed on February 13, 2023. the disclosure of which is hereby incorporated by reference in its entirety.

FIELD AND BACKGROUND OF THE INVENTION

[0002] The present invention relates to a seat assembly for use in an automotive vehicle. More particularly, the invention relates to a molded polyester pad for use in an automotive seat assembly.

DESCRIPTION OF RELATED ART

[0003] Automotive vehicles typically include one or more seat assemblies having a seat cushion and a seat back for supporting a passenger above a vehicle floor. Certain known seat cushions include a molded base pad commonly made of a polyurethane (PU) foam. The trim cover is typically attached to the molded base pad by mechanical fasteners such as clips, hog rings, hook and loop fasteners, and the like. It is commonly known for certain seat assemblies to include trim covers covering portions of the seat cushion or the seat back. The trim covers commonly include an outer surface layer formed out of a cloth, a vinyl, and/or a leather. One commonly used cloth is a polyester cloth.

[0004] However, the molded base pad is not recyclable when the molded base pad includes a polyurethane foam.

[0005] Certain other known molding processes utilize polyester (PET) fibers blown into a closed mold tool to produce a molded base pad. However, the molding process utilizing PET fibers blown into the closed mold often results in randomized hard or soft spots within the resulting base pad.

[0006] It is desirable for the molded base pad to be formed out of commonly recycled materials such as polyester so that the molded base pad may be recycled. In addition, it is desirable to prevent randomized hard or soft spots within the molded base pad when the base pad comprises polyester fibers. SUMMARY OF THE INVENTION

[0007] According to one embodiment, there is provided a molded base pad for an automotive seat assembly. The molded base pad includes a polyester batting blocker comprising a random web of bulk polyester fibers and melt polyester fibers which has been compressed and heated to form the molded base pad having a 3 -dimensional shape. At least a portion of the melt polyester fibers have melted and bonded with at least some of the bulk polyester fibers. Further, the molded base pad includes an outer portion surrounding an inner portion with the inner portion having an inner firmness, the outer portion having an outer firmness, and the inner firmness is different than the outer firmness.

[0008] According to another embodiment, there is provided a method for producing a molded base pad made of polyester batting. The method includes the steps of providing a batting blocker comprising a random web of bulk polyester fibers and melt polyester fibers, placing the batting blocker into a mold cavity, heating the mold cavity using conduction heating, applying a negative atmospheric pressure to the mold cavity, supplying forced heated air into the mold cavity such that the forced heated air is drawn through the batting blocker and towards the negative atmospheric pressure, and compression molding the batting blocker to form the molded base pad.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Advantages of the present invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:

[0010] Figure 1 is a perspective view of a seat assembly including a seat cushion, a seat back, and trim cover assemblies covering the seat cushion and the seat back, according to one embodiment of the present invention;

[0011] Figure 2 is an exploded perspective view of a portion of the seat assembly of Figure 1;

[0012] Figure 3 is an upper perspective view of a molded base pad, according to one embodiment of the present invention;

[0013] Figure 4 is a lower perspective view of the molded base pad of Figure 3; [0014] Figure 5 is cross-sectional view of the molded base pad of Figure 3 taken along section 5-5 in Figure 3;

[0015] Figure 6 is a perspective view of a rectangular block of polyester batting, according to one embodiment of the present invention;

[0016] Figure 7 is a perspective view of a polyester batting blocker cut from the block of polyester batting of Figure 6, according to one embodiment of the present invention;

[0017] Figure 8A shows a cross-sectional view of a monofilament polyester fiber, according to another embodiment of the present invention;

[0018] Figure 8B shows a cross-sectional view of a bi-component polyester fiber having a side- by-side cross-section, according to another embodiment of the present invention;

[0019] Figure 8C shows a cross-sectional view of a bi-component polyester fiber having a core and sheath cross-section, according to another embodiment of the present invention;

[0020] Figure 8D shows a cross-sectional view of a bi-component polyester fiber having a mixed fiber cross-section, according to another embodiment of the present invention;

[0021] Figure 9 shows a perspective view of a molding machine having an upper mold and a lower mold, according to one embodiment of the present invention;

[0022] Figure 10 shows a lower perspective view of the molding machine of Figure 9;

[0023] Figure 11 shows a lower perspective view of the upper mold of Figure 10;

[0024] Figure 12 shows a rear perspective view of the molding machine of Figure 10;

[0025] Figure 13 shows a rear perspective view of the molding machine of Figure 12;

[0026] Figure 14 is a cross-sectional view of the molding machine of Figure 13, showing the upper and lower molds;

[0027] Figure 15 is a perspective view of the molding machine of Figure 13 after the batting blocker of Figure 7 is inserted into a mold cavity' in the lower mold; [0028] Figure 16 is a cross-sectional view of the batting blocker and the upper and low er molds of Figure 15;

[0029] Figure 17 is a cross-sectional view of the upper and lower molds of Figure 16 while the upper mold is compressing the batting blocker to form the molded base pad of Figure 4;

[0030] Figure 18 is a perspective view of the molding machine of Figure 15 after the upper mold is disengaged from the lower mold and showing the molded base pad within the mold cavity in the lower mold;

[0031] Figure 19 is cross-sectional view of a molded base pad having dual densities, according to a second embodiment of the present invention; and

[0032] Figure 20 is a perspective view of a polyester batting blocker having dual densities, according to the second embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0033] Figures 1-20 illustrate a molded base pad 10 for use in an automotive vehicle seat assembly 12 and a process of forming the molded base pad 10 according to embodiments described herein. Directional references employed or shown in the description, figures, or claims, such as top, bottom, upper, lower, upward, downward, lengthwise, widthwise, left, right, and the like, are relative terms employed for ease of description and are not intended to limit the scope of the invention in any respect. Referring to the Figures, like numerals indicate like or corresponding parts throughout the several views.

[0034] Depicted in Figures 1 and 2, the seat assembly 12 includes a seat cushion 14 and a seat back 16 pivotally coupled to the seat cushion 14. The seat cushion 14 typically includes a molded base pad 10 (hereinafter, “base pad”) forming a support layer within the seat assembly 12. The seat assembly 12 also includes trim cover assemblies 18 which are assembled over one or more exterior surfaces of the seat assembly 12 and cover the base pad 10 and other components in the seat assembly 12 to provide a seating surface for an occupant of the automotive vehicle.

[0035] An exemplary base pad 10 for the seat cushion 14 is shown in Figures 3-5. The exemplary base pad 10 includes a side surface 20 extending between opposing upper and lower surfaces 22, 24 and extending around an outer perimeter of the upper and low er surfaces 22, 24. The upper and lower surfaces 22, 24 have a molded 3-dimensional shape and optionally include one or more molded features 26. In addition, the upper and lower surfaces 22, 24 are alternatively described as the “A-surface” and the “B-surface”, respectively. As illustrated in Figure 5, the base pad 10 includes an outer portion 28 extending around the outer perimeter of the base pad 10 and an inner portion 30 surrounded by the outer portion 28. The inner portion 30 optionally has an inner density and/or an inner firmness that is different than an outer density and/or an outer firmness, respectively, of the outer portion 28, as further described below. In certain embodiments, the inner density and/or the inner firmness of the inner portion 30 is less than the outer density and/or the outer firmness, respectively, of the outer portion 28. Firmness typically is evaluated as the amount of force required to indent a surface of a sample by 25% of the uncompressed height of the sample, also described as the indention force deflection (IFD).

[0036] Referring to Figure 6, the base pad 10 is formed from a block 32 of polyester batting 34 having an initial density 36 and/or an initial firmness 36. The polyester batting 34 is alternatively described as polyethylene terephthalate batting (hereinafter, “PET batting”). The block 32 is optionally formed by assembling one or more layers of PET batting 34 in sheet form to obtain a desired batting thickness 37.

[0037] The PET batting 34 is formed out of a random web 38 of bulk polyester fibers 40 and melt polyester fibers 42. The bulk polyester fibers 40 generally include one or more of virgin polyester fibers (PET), recycled polyester fibers (rPET), bio-based polyester fibers, natural polyester fibers, and the like as non-limiting examples.

[0038] Referring to Figures 8A-8D, the melt polyester fibers 42 might include monofilament polyester fibers 44 and/or bi-component polyester fibers 46. The monofilament polyester fibers 44 generally have a melting temperature less than the melting temperature of the bulk polyester fibers 40. The monofilament polyester fibers 44 have a cross-section comprising a single type of polyester fiber 48, as shown in Figure 8A. The melting temperature of the monofilament polyester fibers 44 and the ratio of the bulk polyester fibers 40 relative to the monofilament polyester fibers 44 are selected based in part on the desired flexibility and structural stability of the PET batting 34.

[0039] Further, the bi-component polyester fibers 46 comprise high-temp polyester fibers 50 and low-temp polyester fibers 52 which are simultaneously extruded to combine the physical and aesthetic properties of two different polyester fibers 50, 52. The low-temp polyester fibers 52 are selected to have a melting temperature less than the melting temperature of the high- temp polyester fibers 50. The low-temp polyester fibers 52 preferably have a melting temperature greater than or equal to about 100 °C and less than or equal to about 180 °C. In another embodiment, the low-temp polyester fibers 52 have a melting temperature equal to or greater than about 100 °C and less than or equal to about 130 °C. In a preferred embodiment, the low-temp polyester fibers 52 have a melting temperature of about 120 °C and the high- temp polyester fibers 50 have melting temperature of about 180 °C or greater. The high-temp polyester fibers 50 provide additional structure and durability to the bi-component polyester fibers 46.

[0040] Referring to Figures 8B-8D, the bi-component polyester fibers 46 are formed by simultaneously extruding the high-temp polyester fibers 50 and the low-temp polyester fibers 52 using generally known methods to form a variety of cross-sections 54A-54C. The bi- component polyester fibers 46 might have a side-by-side extruded cross-section 54A (Figure 8B), a core-and-sheath extruded cross-section 54B (Figure 8C), an extruded mixed fiber crosssection 54C (Figure 8D), and the like as non-limiting examples. It will be appreciated that the cross-section 54A-54C of the bi-component polyester fibers 46, as well as the melting temperature of the high-temp polyester fibers 50 and the low-temp polyester fibers 52, respectively, might vary without altering the scope of the present invention. In addition, it will be appreciated that the melting temperature might alternately be described as a molding temperature without altering the scope of the present invention.

[0041] Referring to Figure 6, the PET batting 34 in one exemplary embodiment includes at least about 60% and less than or equal to about 90% bulk polyester fibers 40 and at least about 10% and less than or equal to about 40% melt polyester fibers 42. It will be appreciated that the PET batting 34 might contain up to about 5% of dyes and other additives without varying the scope of the present invention. The percentage of melt polyester fibers 42is selected based in part on the desired firmness of the molded base pad 10. For example, the PET batting 34 might include a low percentage of melt polyester fibers 42when a “soft” molded base pad 10 is desired. In comparison, the PET batting 34 might include a high percentage of melt polyester fibers 42when a “firm” molded base pad 10 is desired. In one exemplary embodiment, the PET batting 34 includes about 85% bulk polyester fibers 40 and about 15% melt polyester fibers 42. Further, the PET batting 34 has a batting thickness 37 selected based in part on the desired thickness of the base pad 10. It will be appreciated that the batting thickness 37 of the PET batting 34 might vary’ without altering the scope of the present invention.

[0042] The random web 38 of the bulk polyester fibers 40 and the melt polyester fibers 42forming the PET batting 34 might be stabilized using various known methods, commonly described as a multi-knit batting, a non-woven batting, a hot-melt batting, and the like, as nonlimiting examples. The multi-knit batting is typically formed by stitch-bonding the random web 38 with longitudinal yams (not shown) to bond and hold the random web 38 in place. The non-woven batting is ty pically formed by needles punched through the random web 38 to push the random w eb 38 into a consistent stable batt. The hot-melt batting is typically formed from a random web 38 which includes bulk polyester fibers 40 and melt polyester fibers 42. To form the hot-melt batting, the random web 38 is passed through a w armer (not shown) which causes at least part of the melt polyester fibers 42 to melt and bond with the remaining polyester fibers 40, 42, in the random web 38. In addition, the PET batting 34 containing bi-component polyester fibers 46 might be preheated or "‘tempered” while the PET batting 34 is still in sheet form (before cutting) to allow at least part of the bi-component polyester fibers 46 to fuse together which improves the structure and stability of the PET batting 34.

[0043] It w ill be appreciated that the properties of the PET batting 34 are customizable for various seating applications by varying the fiber denier, the ratio and properties of the bulk polyester fibers 40 and the melt polyester fibers 42the batting thickness 37, the inclusion of monofilament polyester fibers 44 and/or bi-component polyester fibers 46, the selection of specific high-temp polyester fibers 50 and low-temp polyester fibers 52 within the bi- component polyester fibers 46. the cross-section 54A-54C of the bi-component polyester fibers 46, the inclusion of a batt stabilization method, and the like, to obtain a desired balance of flexibility, structure, and air permeability. In addition, the melting temperatures of the polyester fibers 40, 42, 44, 46, 50, 52 are selected based in part on the selected processing steps to prepare the base pad 10, as further described below. Also, it will be appreciated that the polyester fibers 40, 42, 44, 46, 50, 52 optionally comprise recycled polyester fibers (rPET) which are polyester fibers spun from flakes prepared by flaking post-consumer PET plastic bottles.

[0044] In one embodiment of the present invention shown in Figures 3 and 4, the base pad 10 formed by molding the PET batting 34 serves a similar function to a conventional polyurethane foam base pad for use in certain seat assemblies. Replacing the conventional polyurethane foam base pad with the base pad 10 formed from PET batting 34 allows the base pad 10 to be recycled since the base pad 10 lacks polyurethane content. Optionally, the base pad 10 can be recycled either mechanically, chemically, or by melting so that the polyester content might be respun into new recycled polyester fibers (rPET). As such, the base pad 10 might be recycled instead of disposing the molded base pad 10 in a landfill.

[0045] In addition, the molded base pad 10 formed by compression molding the PET batting 34 has increased breathability compared to commonly known molded polyurethane (PU) base pads. Also, the cost of the raw materials to form the base pad 10 from PET batting 34 is typically less than the cost of the raw materials to form a similar shaped pad using polyurethane. Further, the base pad 10 formed by compression molding the PET batting 34 is more homogeneous than a base pad formed by a molding process using blown in PET fibers.

[0046] The process to form the base pad 10 is described in reference to Figures 6, 7, and 9-18. Referring to Figure 6, the block 32 of PET batting 34 has a generally rectangular shape and optionally comprises a plurality of layers of PET batting 34 in sheet form. Next, the block 32 of PET batting 34 is optionally compressed and the outer perimeter 58 of the base pad 10 is cut to form a polyester batting blocker 60 (Figure 7) using a Gerber cutting process, a die-cutting process, or the like as non-limiting examples.

[0047] The base pad 10 is formed from the polyester batting blocker 60 (hereinafter, “batting blocker”) using a compression molding machine 62 to compress and mold the batting blocker 60 into a 3-dimensional shape. In addition, the molding machine 62 heats the compressed batting blocker 60 to at least partially melt the melt polyester fibers 42 and/or the low-temp polyester fibers 52 in the bi-component polyester fibers 46 causing at least some of the melt polyester fibers 42 and/or the low-temp polyester fibers 52 to bond with at least some of the bulk polyester fibers 40 in order to mold the batting blocker 60 into the base pad 10. Referring to Figure 9. the molding machine 62 includes an upper mold 64 (i.e., “upper half ”) and a lower mold 66 (i.e.. “lower half ”). Depicted in Figures 10, 11 and 14. the upper mold 64 includes an upper mold surface 68 having a 3-dimensional shape which creates the lower surface 24 of the base pad 10. The upper mold surface 68 includes a plurality of spaced apart heated air vents 70. Shown in Figure 12, the molding machine 62 includes one or more industrial heat guns 72 fluidly connected to air inlets 74 in the upper mold 64 which in turn are fluidly connected through air channels 75 to the heated air vents 70. The industrial heat guns 72 are configured to provide forced heated air 76 to the heated air vents 70. It will be appreciated that the forced heated air 76 might be provided to the air inlets 74 by alternate sources of forced heated air and/or pressurized heated steam without altering the scope of the present invention. In addition, the upper mold 64 includes integrated heaters 78 configured to warm the upper mold surface 68.

[0048] Referring to Figures 12-14, the lower mold 66 includes a mold cavity 80 having an upward-facing opening 81 with a side wall 82 extending around an outer perimeter of the opening 81 and adjoining a lower mold surface 84. The lower mold 66 also includes a plurality of spaced apart vacuum inlets 86 in the lower mold surface 84. In addition, the lower mold 66 includes a vacuum line 88 fluidly connected to a vacuum outlet 90 which in turn is fluidly connected through vacuum channels 91 to the vacuum inlets 86. Further, the lower mold 66 includes integrated heaters 92 configured to warm the lower mold surface 84. It will be appreciated that the heated air vents 70, air channels 75, and air inlets 74 might be positioned in the lower mold 66 and the vacuum inlets 86, the vacuum outlet 90, and the vacuum channels 91 might be positioned in the upper mold 64 without altering the scope of the present invention.

[0049] Shown in Figure 12, the molding machine 62 includes a hydraulic cylinder 94 configured to transpose the upper mold 64 towards the lower mold 66 when a molding process is initiated. The hydraulic cylinder 94 is configured to apply pressure onto the upper mold 64 while the upper mold 64 is engaged with the lower mold 66 to compress the batting blocker 60 and form the molded base pad 10. The hydraulic cylinder 94 is configured to retract the upper mold 64 away from the lower mold 66 after the molding process is completed.

[0050] Referring to Figures 15 and 16, prior to initiating the molding process, the batting blocker 60 is inserted at least partially through the opening 81 and at least partially into the mold cavity 80 in the lower mold 66. Trim attachment features (not shown), such as hook and loop fasteners, clips, or the like, are optionally assembled with the upper mold 64, the lower mold 66, and/or with the batting blocker 60 prior to initiating the molding process in order to insert-mold the trim attachment features. Depicted in Figure 16, the heaters 78 in the upper mold 64 are electrically energized causing the heaters 78 to radiate heat through the upper mold 64 and warm the upper mold surface 68, as illustrated by arrow 96. Also, the heaters 92 in the lower mold 66 are electrically energized causing the heaters 92 to radiate heat through the lower mold 66 and warm the lower mold surface 84. as illustrated by arrow 97. The heaters 78, 92 are configured to warm the upper and lower mold surfaces 68, 84 to at least about 110 °C and less than or equal to about 180 °C. It will be appreciated that the temperature of the mold surfaces 68, 84 might vary without altering the scope of the present invention. [0051] In addition, forced heated air 76 is supplied to the air inlets 74 which travels through the air channels 75 (arrow 98) and exits through the heated air vents 70 (arrow 100). The forced heated air 76 typically has a temperature of at least about 200 °C and less than or equal to about 275 °C. It will be appreciated that the temperature of the forced heated air 76 might vary' without altering the scope of the present invention. Further, negative atmospheric pressure is applied to the vacuum outlet 90, as illustrated by arrow 104. The negative atmospheric pressure 104 applied to the vacuum outlet 90 causes ambient air in the mold cavity 80 to be drawn into the vacuum inlets 86 (arrow 106), through the vacuum channels 91 (arrow 108) and towards the vacuum outlet 90.

[0052] Next, the hydraulic cylinder 94 transposes the upper mold 64 towards the lower mold 66 until the upper mold 64 engages with the lower mold 66 and applies pressure onto the batting blocker 60, as illustrated by arrow' 110. Typical tool pressure applied by the hydraulic cylinder 94 onto the batting blocker 60 is between 10 bar - 17 bar (150 - 250 psi). However, it will be appreciated that the amount of applied tool pressure might vary’ without altering the scope of the present invention. The batting blocker 60 is compressed by the upper mold 64 causing the batting blocker 60 to take the shape of the upper and lower mold surfaces 68, 84. In addition, the heated mold surfaces 68, 84 conduct heat into the batting blocker 60, as illustrated by arrows 112, 114, respectively. The conducted heat 112, 114 is typically sufficient to mold a thin layer of PET batting 34. as represented by an outer portion 28 of the compressed batting blocker 60. However, the conducted heat 1 12, 1 14 is insufficient to transfer completely through a thick layer of PET batting 34. Thus, an inner portion 30 of the batting blocker 60 might receive insufficient conducted heat 112, 114 from the heated mold surfaces 68, 84 to mold the inner portion 30.

[0053] In order to mold the inner portion 30 of the batting blocker 60, forced heated air 76 is blown through the heated air vents 70 in the upper mold 64 and through the batting blocker 60 which transfers heat via convection. The negative atmospheric pressure (arrow 104) applied to the vacuum outlet 90 assists with drawing the forced heated air 76 through the batting blocker 60. In more detail, the forced heated air 76 is supplied to the air inlets 74 (arrow 76) and negative atmospheric pressure (arrow 104) is applied to vacuum outlet 90 during the molding process. The forced heated air 76 travels through the air channels 75 (arrow 98) and is exhausted through the heated air vents 70 (arrow 100) and into the mold cavity 80. After the upper mold 64 engages with the lower mold 66, the negative atmospheric pressure (arrow 104) applied to the vacuum outlet 90 draws forced heated air 76 exhausted out of the heated air vents 70 (arrow 100) through the batting blocker 60 (arrow 118). into the vacuum inlets 86 (arrow 106). through the vacuum channels 91 (arrow 108), and out of the vacuum outlet 90. The forced heated air 76 is optionally exhausted to ambient air after exiting the vacuum outlet 90. Alternatively, the exhausted heated air 76 might be recycled and reused as part of the forced heated air 76 provided to the air inlets 74. The batting blocker 60 is moldable using a combination of convection heat transfer and conduction heat transfer when the batting blocker 60 is too thick to be molded using only conduction heat transfer from the mold surfaces 68, 84.

[0054] The molding machine 62 applies pressure and heat to the batting blocker 60 to mold the base pad 10 with a typical cycle time of about 2 minutes to about 7 minutes. It will be appreciated that the cycle time may vary without altering the scope of the present invention. The outer portion 28 of the resulting base pad 10 may have an outer density and/or outer firmness greater than the inner density’ and/or inner firmness, respectively, of the inner portion 30 since both the convective heat 118 from the forced heated air 76 and the conductive heat 112, 114 from the mold surfaces 68, 84 travel into the outer portion 28 while the conductive heat 112, 114 has less effect on the inner portion 30 due to the original thickness of the batting blocker 60. The relative firmness of the outer portion 28 and the inner portion 30 may be adjusted by modifying the temperature of one or more of the upper and lower mold surfaces 68, 84, the cycle time, and/or the temperature of the forced heated air 76. In certain applications it is desirable to increase the firmness of the outer portion 28 relative to the inner portion 30. For example, a firmer outer portion 28 of the base pad 10 may be desired when adhesively bonding trim cover attachment features (not shown) to the base pad 10.

[0055] After the molding cycle time is completed, the hydraulic cylinder 94 transposes the upper mold 64 away from the lower mold 66, as illustrated by arrow- 120 in Figure 18. Next, the molded base pad 10 is removed from the mold cavity 80 in the lower mold 66. as illustrated by arrow 122. Optionally, trim cover attachment features (not shown), such as hook and loop fasteners, clips, and the like, are adhesively attached to the outer portion 28 of the base pad 10.

[0056] A second embodiment of the base pad 10-1 is shown in Figures 19 and 20. where reference numerals designated with '‘-1” represent similar elements as those described above. The base pad 10-1 is a dual-density base pad 10-1 formed by stacking multiple batting blockers 60a, 60b to form a dual density blocker 60-1 prior to molding the base pad 10-1. For certain seating applications, it may be desirable to have a base pad 10-1 having a firm lower portion 30b and a less firm upper portion 30a, as a non-limiting example. Only significant differences between the previous embodiments are reflected in the Figures and the description below.

[0057] Referring to Figure 19. the dual-density base pad 10-1 includes a first region 28a, 30a having a different density and/or a different firmness than a second region 28b. 30b. respectively, as further described below. Shown in Figure 20, the dual density blocker 60-1 includes a first batting blocker 60a of PET batting 34-1 stacked on top of a second batting blocker 60b of PET batting 34-1. The first batting blocker 60a comprises a first random web of bulk polyester fibers and melt polyester fibers having a first initial density and/or a first initial firmness 36a. The second batting blocker 60b comprises a second random web of bulk polyester fibers and melt polyester fibers having a second initial density and/or a second initial firmness 36b wherein the first initial density 36a is different than the second initial density' 36b and/or the first initial firmness 36a is different than the second initial firmness 36b.

[0058] To mold the dual density' base pad 10-1, the dual density blocker 60-1 is inserted into the mold cavity 80, as shown in Figure 16. Next, the molding machine 62 compresses and heats the dual density blocker 60-1 between the upper and lower molds 64, 66 to form the molded base pad 10-1 having dual densities. The outer portion 28a formed from the first batting blocker 60a might have a different density and/or different firmness than the outer portion 28b formed from the second batting blocker 60b due, in part, to the difference in the initial densities and/or initial firmness 36a, 36b of the batting blockers 60a, 60b.

[0059] It will be appreciated that the properties of the PET batting 34-1 in the first and second batting blockers 60a, 60b are customizable for various seating applications by varying the fiber denier, the ratio and properties of the bulk polyester fibers 40 and the melt polyester fibers 42, the batting thickness 37, the inclusion of monofilament polyester fibers 44 and/or bi-component polyester fibers 46, the selection of specific high-temp polyester fibers 50 and low-temp polyester fibers 52 within the bi-component polyester fibers 46, the cross-section 54A-54C of the bi-component polyester fibers 46, the inclusion of a batt stabilization method, and the like, to obtain a desired balance of flexibility, structure, and air permeability. In addition, the melting temperatures of the polyester fibers 40. 42. 44, 46, 50, 52 are selected based in part on the selected processing steps to prepare the base pad 10-1, as further described below. For example, one of the first and second batting blockers 60a, 60b might have a larger percentage of melt polyester fibers 42 in comparison to the percentage of melt polyester fibers 42 in the other one of the first and second batting blockers 60a, 60b.

[0060] As discussed above, the molded base pad 10, 10-1 of the present invention is formed by compression molding the PET batting 34, 34-1 with heated mold surfaces 68, 84 and while forced heated air 76 passes through the mold cavity 80. Further, the properties of the PET batting 34. 34-1 are customizable so that the PET batting 34, 34-1 might replace conventional polyurethane foam base pads used in conventional seat assemblies.

[0061] The invention has been described in an illustrative manner, and it is to be understood that the terminology, which has been used, is intended to be in the nature of words of description rather than of limitation. Many modifications and variations of the present invention are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims, the invention may be practiced other than as specifically described.

Claims

What is claimed is:

1. A molded base pad for an automotive seat assembly, comprising: a polyester batting blocker comprising a random web of bulk polyester fibers and melt polyester fibers which has been compressed and heated to form the molded base pad having a 3-dimensional shape with at least a portion of the melt polyester fibers having melted and bonded with at least some of the bulk polyester fibers; wherein the molded base pad comprises an outer portion surrounding an inner portion with the inner portion having an inner firmness, the outer portion having an outer firmness, and the inner firmness is different than the outer firmness.

2. The molded base pad as set forth in claim 1, wherein the inner firmness is less than the outer firmness.

3. The molded base pad as set forth in claim 1. wherein the inner portion having an inner density, the outer portion having an outer density, and the inner density is different than the outer density.

4. The molded base pad as set forth in claim 3, wherein the inner density is less than the outer density.

5. The molded base pad as set forth in claim 1, wherein the polyester batting blocker comprises: at least 60% and less than or equal to 90% of bulk polyester fibers; and at least 10% and less than or equal to 40% of melt polyester fibers.

6. The molded base pad as set forth in claim 5, wherein the bulk polyester fibers comprise one or more of virgin polyester fibers, recycled polyester fibers, bio-based polyester fibers, and natural polyester fibers.

7. The molded base pad as set forth in claim 6, wherein: the polyester batting blocker comprises 5% or less of dyes or other additives.

8. The molded base pad as set forth in claim 5, wherein the polyester batting blocker comprises about 85% bulk polyester fibers and about 15% melt polyester fibers.

9. The molded base pad as set forth in claim 5, wherein: the melt polyester fibers comprise bi-component polyester fibers; and the bi-component polyester fibers comprise high-temp polyester fibers and low-temp polyester fibers, the low-temp polyester fibers having a melting temperature greater than or equal to 100 °C and less than or equal to 180 °C, and the high-temp polyester fibers having a melting temperature greater than the melting temperature of the low-temp polyester fibers.

10. The molded base pad as set forth in claim 9. wherein the low-temp polyester fibers have a melting temperature of about 120 °C.

11. The molded base pad as set forth in claim 9, wherein the bi-component polyester fibers have a side-by-side cross-section, core and sheath cross-section, or a mixed fiber cross-section.

12. The molded base pad as set forth in claim 5, wherein the polyester batting blocker further comprises: a first polyester batting blocker having a first initial density; and a second polyester batting blocker having a second initial density different than the first initial density; wherein the first polyester batting blocker is stacked on top of the second polyester batting blocker to form the polyester batting blocker prior to compression molding the polyester batting blocker to form the molded base pad.

13. A method for producing a molded base pad made of polyester batting, the method comprising: providing a batting blocker comprising a random web of bulk polyester fibers and melt polyester fibers; placing the batting blocker into a mold cavity; heating the mold cavity' using conduction heating; applying a negative atmospheric pressure to the mold cavity; supplying forced heated air into the mold cavity such that the forced heated air is drawn through the batting blocker and towards the negative atmospheric pressure; and compression molding the batting blocker to form the molded base pad.

14. The method as set forth in claim 13. wherein the polyester batting comprises at least 60% and less than or equal to 90% bulk polyester fibers and at least 10% and less than or equal to 40% melt polyester fibers.

15. The method as set forth in claim 14, wherein: the melt polyester fibers include bi-component polyester fibers which include high- temp polyester fibers and low-temp polyester fibers; the low-temp polyester fibers have a melting temperature greater than or equal to 100 °C and less than or equal to 180 °C; and the high-temp polyester fibers having a melting temperature greater than the melting temperature of the low-temp polyester fibers.

16. The method as set forth in claim 15, wherein at least a portion of the low-temp polyester fibers melt at a molding temperature of at least 100 °C and less than or equal to 180 °C during the compression molding.

17. The method as set forth in claim 16, wherein the bi-component polyester fibers have a melting temperature equal or greater than 100 °C and less than or equal to 130 °C.

18. The method as set forth in claim 13, further comprising steps of: providing a first batting blocker comprising a first random web of bulk polyester fibers and melt polyester fibers and having one or more of a first initial density and a first initial firmness; providing a second batting blocker comprising a second random web of bulk polyester fibers and melt polyester fibers and having one or more of a second initial density and a second initial firmness wherein the second initial density is different than the first initial density and the second initial firmness is different than the first initial firmness; stacking the first batting blocker on top of the second batting blocker to form the batting blocker prior to the compression molding the batting blocker.