HK1132636A - Mattress with flame resistant moisture barrier - Google Patents

Description

Mattress with fire-proof moisture barrier

Cross reference to other patent applications

This application claims priority from U.S. provisional patent application No.60/618348 filed on 12.10.2004, the entire contents of which are incorporated herein by reference.

Background

In the mattress industry, it is well known that in certain environments it is desirable to provide a mattress with a moisture barrier to prevent unwanted fluid leakage or passage into the lower portion of the mattress. In box spring mattresses, particularly in a hospital or other health care environment, it is desirable to prevent water, urine, or other liquids from passing through the upholstery cover of the mattress and into the innerspring portion of the mattress. Once fluid enters the innerspring portion of the mattress, the fluid is difficult to remove and may cause undesirable results.

Waterproof materials such as vinyl have been used to provide a moisture barrier. In some designs, the moisture barrier is formed to resemble a slipcover that can be slid over the mattress and secured by zippers, buttons, or other means. In other designs, the moisture barrier is a layer of material that is positioned below the decorative layer and above the innercore, thereby providing a moisture barrier between the sleeping user and the innercore. But these layers are difficult to sew or otherwise secure within the mattress. Vinyl groups are, for example, easily torn once they have been sewn or punctured. To address this problem, engineers and designers have been developing improved materials and processes for manufacturing mattresses. These improved materials retain their shear strength even when they are sewn or otherwise punctured by C-pins (hog-rings), clips, or other connectors. An example of such a material is the material described in US 5311624.

While these moisture barriers work well, they still present problems. Upholstery that provides a removable upholstery top often uses a zipper or some other attachment mechanism that secures the upholstery cover to the mattress core. Recent initiatives have been taken to limit and restrict how a mattress can work when exposed to open flames. These attachment mechanisms, particularly zippers, can create a point of failure for open flame testing.

Accordingly, there is a need in the art for materials and systems that can act as moisture barriers without causing the mattress to fail open flame compliance tests.

Disclosure of Invention

The systems and methods described herein include an improved mattress and an improved layer of material for providing a mattress with a moisture barrier that is resistant to open flames. Additionally, the invention includes methods of making mattresses and making moisture barrier materials that can be used as barriers within mattresses.

In one aspect, the systems and methods described herein include, but are not limited to, a cushion having: an inner core defining an upper major surface; a liquid-resistant barrier for inhibiting the passage of liquids, the liquid-resistant barrier having a liquid-resistant layer for inhibiting the passage of liquids, a structural backing layer, and at least one fire-blocking layer. Optionally, the cushion may also have a cover, such as a trim cover, and further optionally, the cover may be removable.

The liquid-proof layer may be liquid and/or moisture resistant and may for this purpose comprise a material selected from the group consisting of polyurethane, polyvinyl chloride, vinyl, amide, polyester, MYLARRubber, neoprene, wool, Polytetrafluoroethylene (PTFE), and NANOPELFibers selected from the group consisting of cellulose esters. The liquid-repellent layer may comprise a layer of material that has been surface treated so that it resists penetration of moisture in at least one direction. This may be a layer of foam, cotton, wool or some other treated material, typically using a chemical compound, whereby the layer may preventThe passage of liquid or moisture. The liquid-resistant barrier may be disposed along the sidewall of the innercore above the upper surface of the innercore, above the lower surface of the innercore, or in any location that prevents the penetration of moisture or flame, heat, or fire. In one embodiment using a removable cover, the fire resistant moisture barrier is positioned adjacent the innercore such that the barrier provides a backing layer positioned adjacent where zippers, hook and loop fasteners, or other fasteners will be positioned. In a further embodiment, the liquid-proof barrier has a fire-resistant layer extending across the moisture barrier and having a dimension greater than the moisture barrier. This allows the fire-blocking layer to be placed at a location that is advantageous for fire protection, but does not require a moisture barrier. In an alternative embodiment, the cushion may have a removable cover, with the liquid resistant layer disposed within the removable cover.

The fire-blocking layer may be any suitable fire-blocking layer including a material selected from the group of kevlar fibers, halogenated fibers, refined fibers, and non-organic fibrous materials. The flame resistant layer may include a plurality of layers of flame resistant material and may be disposed adjacent the innercore at a location proximate to a location of the attachment mechanism for securing the removable cover to the innercore.

The cushion may be a mattress, sofa cushion, futon or any other furniture cushion having an inner resilient body or core. The liquid-resistant barrier may be disposed adjacent at least a portion of that innercore and may be attached to the innercore by attachment means such as C-clips, plastic tape, adhesives, staples, and pins. In some embodiments, the innercore may be a foam wrap and the liquid-resistant barrier covers at least a portion of the foam sidewall. Alternatively, the liquid-resistant barrier may surround all or substantially all of the innercore and for this purpose may be a bag-like container sized to surround at least a portion of the innercore.

In another aspect, the systems and methods described herein include a moisture barrier with a fire retardant layer and methods of making the moisture barrier and cushion, including mattresses having the layers.

Brief description of the drawings

The following figures depict some exemplary embodiments of the present invention, in which like reference numerals refer to like elements. The above-described embodiments should be understood as merely illustrative, and not restrictive in any way.

FIG. 1A depicts one embodiment of a moisture barrier material according to the present invention;

FIG. 1B is an end exploded schematic view of one embodiment of an inner spring configuration, packing layers and spacers according to the present invention;

FIG. 2 is an end assembly view of the foregoing components with the addition of a removable cover removed therefrom;

FIG. 3 is an alternative embodiment of the present invention;

FIG. 4 is a side exploded view of a water mattress according to the present invention;

fig. 5 is a partial cross-sectional view of the side of a pocketed spring according to the invention.

Detailed Description

In order to provide a thorough understanding of the present invention, certain illustrative embodiments and practices will now be described, including a fire resistant moisture barrier and a mattress and a method of manufacturing a mattress with a fire resistant moisture barrier. However, those of ordinary skill in the art will appreciate that the above-described systems and methods may be altered and modified and may be used for other purposes, such as for sofas, futons or other furniture or cushions for furniture, and that other additions, modifications and uses will not depart from the scope of the present invention.

Referring now to the drawings, in which like numerals represent like elements throughout the several views, FIGS. 1-5 illustrate various embodiments and practices that may be implemented using the techniques described herein.

Fig. 1A depicts a first embodiment of a moisture barrier material having fire retardant properties. Specifically, FIG. 1A depicts an embodiment of a moisture barrier material 10, the moisture barrier material 10 including a moisture barrier layer 12, a backing material layer 14, and two layers of fire retardant material 18.

More specifically, the moisture barrier layer 12 may be a 1 mil PU (polyurethane) film. The moisture barrier 12 may optionally have an antimicrobial additive applied to its outer surface or added to the film during manufacture. The antimicrobial agent may inhibit the growth of mold, mildew, and bacteria, and by itself or in combination with a moisture barrier, may prevent the transmission of dust mites. Other thicknesses of PU (polyurethane) film, including 2-5 mils, may also be used. In addition, other materials may be used, either in place of polyurethane or in combination with polyurethane. Other materials may include vinyl, polyester, wool, organic fleece, plastic, treated canvas, treated cotton, or combinations of the above, such as combinations of material layers capable of acting as moisture or vapor barriers. In addition, other polymeric compositions may be used as both sheets of material and as a cover layer applied to sheets of normally porous material, such as clothing, and the choice of material for the moisture barrier layer 12 will depend on the future application.

Fig. 1A also depicts a liner layer 14 that in this embodiment comprises a layer of PET (polyester) strands. In the described embodiment, the PET (polyester) strands are at least partially overlapped to form a mesh structure commonly referred to as a scrim. The strands may have any suitable thickness and are typically in the range of 1-10 mils, and more typically 3-5 mils. The backing layer 14 may comprise strands of other materials and thicknesses, such as polypropylene, polyethylene, aluminum, or fiberglass, as well as combinations of such materials. In any event, the backing layer 14 provides an increased integrity level of the constructed backing layer to the moisture barrier 12, thereby reducing the likelihood of cracks forming during mattress manufacture and later use. Similarly, the scrim 14 may also provide an increased level of integrity to the one or more fire-blocking layers 18.

FIG. 1A also illustrates that in this embodiment, the compartment 10 is enclosedComprising two layers 18 of fire-resistant material. In one embodiment the fire-blocking material is KEVLAR^TMAnd PET (polyester) binder fibers, although other suitable materials may be used, and the actual material used will depend on the details of the application, including the mattress type (e.g., open coil, pocketed spring, foam, water), mattress size, material cost, and other such design considerations. In the illustrated embodiment, a layer of fire retardant material 18 may be provided on either side of the backing layer (scrim) 14. In this manner, the backing layer 14 is sandwiched between two layers 18 of fire-blocking material. The backing layer 14 may be attached to the layer of flame retardant material 18 by an adhesive, solvent, ultrasonic welding, or any suitable technique. Alternatively, in some embodiments, the backing layer 14 may be formed without one or more layers 18 attached, and in such embodiments the scrim 14 holds the peripheral edge of the innercore in place with sufficient force to prevent or reduce the likelihood of the moisture barrier 12 or fire barrier layer 18 tearing due to movement of the innercore.

As mentioned above, layer 18 is described as being formed from KEVLAR formed as a fabric layer^TMFibers and PET fibers. In one practice, the fabric layer is formed by mixing and connecting fibers with a binder or adhesive. In other embodiments, layer 18 may be a KEVLAR^TMAnd a fabric layer formed of a woven fabric of PET fibers. Other techniques may be used to form layer 18, and any suitable technique for forming layer 18 may be used. The layer 18 shown in fig. 1A is kevlar, but other suitable materials may be used in other embodiments. The other materials may be other fire-blocking materials, or what is sometimes referred to as flame or fire retardant materials, and may include any commercially available fire-blocking material. The above materials can be classified into four general groups including inorganic materials, organic phosphorus materials, halogenated organic materials (typically halogenated with chlorine or ordinary bromine), and nitrogen-based compounds. Commercially available materials are sold under the trade names NOMEX, KEVLAR, INDURA and others. Other materials include fire-resistant balanced core-spun (coreespun) yarns as described in US 5540980. The material may comprise a layer or fibres incorporated in a layerWherein the fibers are chopped fibers, rayon, spun yarns, and/or continuous filament layers. The type of fiber or layer used will depend on the application. In other embodiments, the fire-blocking layer may be a layer of treated material, such as cotton or polyurethane, wherein the treatment provides a degree of fire-blocking. Fire resistant or flame retardant papers may also be used. Other fire-blocking materials may also be used without departing from the scope of the present invention.

Alternatively, the moisture barrier 10 may have other layers including additional layers of fire retardant, liner or moisture resistant materials. The layers described above may be laminated together, ultrasonically welded, bonded together by adhesives or solvents, or otherwise combined to form a sheet of material. The size of the sheet formed may vary depending on the application, but in some embodiments the size of the sheet may be conventional for mattress manufacture, which is typically about 88 inches wide.

Turning now to fig. 1B, there is depicted the material 10 of fig. 1A for use in an innerspring mattress assembly. As can be seen, the innerspring construction 15 includes a pair of border wires 11 and defines an upper surface 16, a lower surface 17 and side surfaces. The construction 15 of the innerspring may be an open coil construction as shown, it may be a pocketed spring construction as identified in U.S. patent No.4234933 to Stumpf, or it may be a foam core, or any other suitable core, or combination of cores, which is incorporated herein by reference.

One or more moisture barrier layers 10 may be provided on the upper and lower surfaces of the inner core construction 15 so that the layers 10 overlap the boundary line 11. The layer 10 may optionally include an insulating layer (e.g., a fiberfill or plastic mesh) and may also include a cotton fiberfill, a polyurethane fiberfill, or other filler material 21 as is known in the art. On top of each decorative layer, the layers of laminated barrier material 10 are "pinned" directly to the springs 22 of the innerspring construction using C-pins 13. In one embodiment, a second layer of barrier material is "stapled" to the lower boundary line 11 and wrapped over the bottom surface 17 of the innercore, thereby leaving another fire resistant moisture barrier for completely surrounding the innercore construction and trim materials. The C-shaped staples are conventional means of attaching fabric or padding to the construction of the innerspring, although other mechanical or adhesive means may be used, including plastic bands, plastic or elastomeric bands, and staples.

In the illustrated embodiment, the barrier 10 is disposed between the upper surface 16 of the innercore 15 and the upholstery, and another sheet of the barrier 10 is disposed between the lower surface 17 of the innercore 15 and the upholstery on the underside or bottom side of the mattress or cushion. In alternative embodiments, the barrier 10 may be disposed along a sidewall or a portion of a sidewall of the innercore 15. For example, in embodiments having a removable decorative cover, a zipper or other fixture is provided on the cover to allow the cover to be removed from the mattress. In the above embodiments, the barrier 10 may be positioned so that it is positioned adjacent to the inner core at any location adjacent to the zipper or fixture. For example, fig. 2 depicts the removable cover 30 having a zipper 34, wherein the zipper 34 extends down the sidewall of the core 15. In this embodiment, the barrier 10, or at least the fire resistant layer of the barrier 10, may be provided along the portion of the innercore sidewall adjacent the zipper 34 to provide a fire resistant liner for the zipper 34.

With the barrier material 10 and upholstery layer in place, conventional upholstery (not shown) may then be applied to the innercore construction, or a removable cover 30 may be placed over the innerspring construction, as shown in FIG. 2. The removable cover 30 may be constructed of conventional upholstery material 32 as used in conventional non-removable mattress covers, or the removable cover 30 may be secured in place by zipping to secure a cover 34 to provide a complete enclosure for the innercore construction and barrier material. The decorative layer of cover 30 may comprise one of an artificial or natural fibrous material, or a mixture thereof. In one embodiment, the fabric layer comprises a nylon material laminated, for example, by heat bonding to a foam sub-layer or layers. Other materials such as polyester or terry stock material or blends thereof, soft organic materials, wool or cotton or other materials may also be used. Also, the cover may include a machine washable fabric layer. The cover 30 may be sewn or rolled to provide a complete exterior. The cover 30 may be attached by a zipper 34 or, if desired, hook and loop fasteners, or some other fastener or combination of fasteners may be used. The resulting mattress or cushion has a complete shape.

It will be appreciated that if the mattress or cushion encounters a liquid spill, for example on its upper surface, the liquid will tend (if conventional upholstery material is used) to leak into the upholstery. If the spillage is sufficient, the liquid may leak completely through the cover and encounter the barrier. At this point it will preferably be stopped or at least prevented. It will be appreciated that it is desirable that the springs or foam of the mattress core should not be contaminated, which as discussed above is detrimental to the springs and padding because the springs and padding are difficult to clean or even access, especially in the case of pocketed springs.

It will be appreciated that alternative embodiments exist to provide a mattress with a fire resistant moisture barrier. Fig. 3 depicts an alternative embodiment in which the fire resistant moisture barrier is built into the inner surface of the removable cover 30. As shown, the removable cover 30 may have the sheet of material 10 attached to one or more of its interior surfaces. Alternatively, a fire resistant layer may surround or be provided adjacent to the zipper 34 in the inner core portion to provide additional fire resistance at the location of the zipper 34. An optional backing layer of FR (fire retardant) material may be provided as well as an optional layer of FR material covering the zipper 34. The zipper 34 may extend along the sidewalls of the cushion or around the peripheral edge of the cushion or any other suitable location, and the barrier 10 may be positioned adjacent the zipper 34.

Fig. 4 shows another embodiment of a water mattress 50. As shown, a laminated fire retardant moisture barrier layer 56 may also be sewn into the upper cover portion 52 of the water mattress 50 to provide a barrier to water or moisture leaking out of the interior water bladder 58 within the mattress 50. As can be seen from the description of the layers illustrated in fig. 1A-1B, the construction of the moisture barrier 56 readily accommodates the stitching described above, and provides improved resistance to tearing or ripping after stitching.

The present invention also provides an improved pocketed spring configuration 60, as shown in fig. 5. The pocketed spring construction 60 includes a spring 61 (as described in U.S. patent No.4234933 to Stumpf) encased in a 4-layer fabric cover. The 4-layer laminate barrier material (40 shown in fig. 3) includes an outer water or moisture sealant layer, a structural backing layer, and two fire resistant layers. In this configuration 60, it can be seen that the encased spring 61 is typically constructed of metal, and the spring 61 is protected by a moisture barrier.

It will be appreciated that the fabric on the spring may be reversed, i.e. the construction liner layer is on the outside, or a moisture barrier and/or fire barrier layer is sandwiched between two layers of scrim. Other arrangements of the barrier 10 may be used without departing from the scope of the invention. It should also be understood that foam, plastic springs, or other resilient materials may also be used as an alternative to the construction of the metal innerspring, and the moisture barrier described herein may protect the alternative springs and resilient materials.

In another aspect, the invention provides methods of making sheets or layers of moisture resistant and fire resistant material and making cushions, such as sofa cushions and mattresses having such barriers. The material may be manufactured as described above to provide a web that may be used to form mattresses and other products described herein.

Thus, it can be seen that a mattress construction is provided that has improved resistance to water, water vapor, or other liquids or vapors, as well as open flames. An improved water mattress construction is also provided which reduces the chance of internal water leakage. Although the present invention has been described in detail with reference to the disclosed embodiments, it should be understood that numerous changes and modifications may be effected within the spirit and scope of the invention as set forth in the appended claims. For example, the mattress may include a foam core, or a combination of foam and springs. The mattress may be one-sided or two-sided. The fire resistant layer may be used in any furniture cushion, including vehicle seat cushions, sofa cushions, and futons. Other applications may include use in pillows, mattress covers, bedspreads, draperies, protective clothing, field fire shields, and the like. Accordingly, those of ordinary skill in the art will know, or be able to ascertain using no more than routine experimentation, various equivalents to the embodiments and practices described herein. Accordingly, it is to be understood that the invention is not to be limited to the embodiments disclosed herein, but is to be understood from the following claims, which are to be interpreted as broadly as allowed under the law.

Claims (16)

1. A cushion structure, comprising:

an inner core defining an upper major surface,

a liquid-resistant barrier for inhibiting the passage of liquids, the liquid-resistant barrier comprising

A liquid-proof layer for preventing liquid from passing through;

constructing a lining layer; and

at least one fire barrier layer.

2. The cushion according to claim 1, further comprising

The cover may be removed.

3. The cushion as in claim 1, wherein

The liquid-repellent layer comprises fibers selected from the group consisting of polyurethane, polyvinyl chloride, vinyl, amide fibers, polyester, mylar, rubber, neoprene, wool, Polytetrafluoroethylene (PTFE), and nanopel.

4. The cushion as in claim 1, wherein

The liquid-repellent layer comprises a layer of material having a surface treatment for inhibiting moisture penetration in at least one direction.

5. The mattress of claim 1, wherein

A liquid-resistant barrier is disposed over the upper major surface of the innercore.

6. The cushion according to claim 1, wherein the inner core has a lower major surface, and further comprising:

a second fire barrier layer disposed over the lower major surface of the innercore.

7. The cushion according to claim 1, wherein the inner core has at least one sidewall, and further comprising:

a second flame resistant layer disposed over a portion of the at least one sidewall.

8. The cushion according to claim 1, wherein the cushion has a lower major surface, and further comprising:

a second liquid-resistant barrier disposed over the lower major surface of the innercore.

9. The cushion according to claim 2, wherein the liquid resistant layer is disposed within the removable cover.

10. The cushion according to claim 1, wherein the fire-blocking layer comprises a material selected from the group of kevlar fibers, halogenated fibers, refined fibers, and non-organic fibrous materials.

11. The cushion according to claim 1, wherein the liquid resistant barrier is attached to the innercore by attachment means selected from the group consisting of C-clips, plastic tape, adhesive, staples, and pins.

12. The cushion according to claim 1, further comprising:

a foam sidewall disposed adjacent at least a portion of the sidewall of the innercore, and wherein the liquid-resistant barrier covers at least a portion of the foam sidewall.

13. The cushion according to claim 1, wherein the liquid resistant barrier comprises a bag-like container sized to enclose at least a portion of the innercore.

14. The cushion according to claim 1, wherein the at least one fire-blocking layer comprises a plurality of layers of fire-blocking material.

15. The cushion according to claim 1, wherein the fire-blocking layer is disposed adjacent the innercore at a location proximate to a location of an attachment mechanism for securing the removable cover to the innercore.

16. A method of manufacturing a mattress comprising the steps of:

providing an inner core; and

attaching the barrier material of claim 1 to at least one surface of the innercore.