WO2016196006A1

WO2016196006A1 - Reusable underpad with spacer fabric, microfiber intermediate layer, and barrier layer

Info

Publication number: WO2016196006A1
Application number: PCT/US2016/032968
Authority: WO
Inventors: Richard Stewart; Saravan Muthanandam
Original assignee: Standard Textile Co., Inc.
Priority date: 2015-05-29
Filing date: 2016-05-18
Publication date: 2016-12-08

Abstract

A reusable underpad (10) for containing liquids that includes a liquid permeable face layer (12), an intermediate layer (14), and a substantially liquid impermeable barrier layer (16). The intermediate layer (14) is intermediate to the face layer (12) and the barrier layer (16). The intermediate layer (14) is comprised of microfiber fabric that is capable of adsorbing, absorbing, or both adsorbing and absorbing a liquid.

Description

REUSABLE UNDERPAD WITH SPACER FABRIC, MICROFIBER INTERMEDIATE LAYER, AND BARRIER

LAYER

FIELD

[0001] The present invention relates to reusable underpads for use in containing bodily fluids. BACKGROUND

[0002] Conventional reusable underpads have three layers with the top two layers being quilted to one another. The three layers are a woven face layer, a nonwoven absorbent layer, and a barrier layer. The face layer is typically a relatively thin liquid permeable fabric that contacts the skin of the subject wearing the underpad. The liquid passes through the face layer into the absorbent layer, which is also sometimes called a soaker. The absorbent layer typically includes one or more layers of wicking and absorbing materials. Conventionally, the absorbent layer is formed from nonwoven, non-knit a bsorbent materials, such as polyester and rayon. The barrier layer is provided as the outermost layer of the underpad and prevents liquid contained in the absorbent layer from soaking through to the user's bed or chair. Oftentimes the barrier layer is both substantially liquid and gas impermeable.

[0003] Conventional reusable underpads are difficult to launder. For example, the materials used in the underpads may not allow for the sufficient flow of wash water to pass through the barrier layer to adequately clean the layers. Additionally, the construction of conventional underpads restricts the flow of air through the pad during drying, which could result in the pad remaining damp or require additional energy to completely dry the pad.

[0004] Additionally, the nonwoven absorbent layers do not stand up well to repeated launderings. For example, the nonwoven structure of the absorbent layers tends to break down and become misshapen after being laundered repeatedly. The absorbent layers also typically used in reusable underpads are relatively thick, and the polyester and rayon fibers used in their construction contributes to the difficulty in laundering the underpads because the materials require a large amount of energy to dry.

[0005] Another problem with conventional reusable pads is that the relatively thin liquid permeable face material allows liquid captured in the absorbent layer to contact the skin of the user. Prolong exposure to dampness in the underpad is unhygienic and can lead to the formation of bed sores.

SUMMARY

[0006] The reusable underpads described herein address one or more of the problems identified above with respect to conventional reusable underpads.

[0007] Accordingly, an aspect of the invention is directed to a reusable underpad for containing liquids that includes a liquid permeable face layer, an intermediate layer, and a substantially liquid impermeable barrier layer is provided. The intermediate layer is intermediate to the face layer and the barrier layer. The intermediate layer is comprised of microfiber fabric that is capable of adsorbing, absorbing, or both adsorbing and absorbing a liquid.

[0008] Various additional objectives, advantages, and features of the invention will be appreciated from a review of the following detailed description of the illustrative embodiments taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with a general description of the invention given above, and the detailed description given below serve to explain the invention.

[0010] FIG. 1 is a perspective view of a reusable underpad with a portion thereof peeled back to show its layers in accordance with embodiments of the invention; [0011] FIG. 2 is an enlarged, cross-sectional view of the reusable underpad of FIG. 1 taken at lines 2-2;

[0012] FIG. 3 is an enlarged, cross-sectional view of the intermediate layer of FIG. 1 taken at lines 3-3 in accordance with embodiments of the invention; and

[0013] FIG. 4 is an enlarged, cross-sectional view of the barrier layer of FIG. 1 taken at lines 4-4 in accordance with embodiments of the invention.

DETAILED DESCRIPTION

[0014] With reference to FIGS. 1 and 2, there is shown an embodiment of a reusable underpad 10 constructed in accordance with the principles of the present invention. To this end, the exemplified reusable underpad 10 has three layers: a face layer 12, an intermediate layer 14, and a barrier layer 16. The face layer 12 is liquid permeable to allow liquid, such as bodily fluids, to pass through the face layer 12 to the intermediate layer 14. The intermediate layer 14 may absorb, adsorb, or both absorb and adsorb the liquid as well as store the liquid that passes through the face layer 12. The barrier layer 16 can prevent liquid in the intermediate layer 14 from escaping or leaking out.

[0015] The face layer 12 has an outer surface 20 that contacts the user of the reusable underpad 10 and an inner surface 22 that is in contact with the intermediate layer 14. Liquid, such as bodily fluids, can pass through the outer surface 20 of the face layer 12 to the inner surface 22 of the face layer 12, whereat the liquid can be absorbed and/or adsorbed by the intermediate layer 14. In the exemplified embodiment of the invention, the face layer 12 is comprised of a liquid permeable spacer fabric 24 having a three-dimensional structure that facilitates air flow, breathability and lightweight shape support. [0016] The exemplified embodiment of the spacer fabric 24 of the face layer 12 has three integrally formed portions: the outer surface 20, a layer of intermediate yarns 26, and the inner surface 22. The outer surface 20 contacts the user, the inner surface contacts the intermediate layer 14 of the underpad 10, and the intermediate yarns 26, which are "spring-like", form a cushion of air between the outer surface 20 and the inner surface 22. The spacer fabric 24 may be knit in one continuous operation and may be warp knit or circular knit. Although the face layer 12 appears to be several fabrics bonded together, it is actually one fabric that cannot be separated into layers. The inner surface 22, intermediate yarns 26, and outer surface 20 may be knit from the same type of yarn or from different types of yarn to form the spacer fabric 24 of the face layer 12. In embodiments of the present invention, the spacer fabric 24 is knit from a hydrophobic yarn such as 100% polyester multi- or mono-filament yarns. In alternative embodiments, the spacer fabric 24 may be knit from other types of yarns, such as polypropylene, nylon, polyethylene, acrylic, and rayon.

[0017] In one embodiment, the outer surface 20 of the face layer 12 has a different mesh than the inner surface 22. For example, the outer surface 20 of the face layer 12 may have a relatively fine mesh, whereas the inner surface 22 may have a larger mesh when compared to the fine mesh of the outer surface 20 and includes relatively large openings 30. The fine mesh of the outer surface 20 presents a hand favorable for contacting the skin of the user and the larger mesh of the inner surface 22 allows for liquid passing through the face layer 12 to more easily and quickly be absorbed and/or adsorbed by the intermediate layer 14. In another embodiment of the face layer 12, the mesh of the outer surface 20 may match the mesh of the inner surface 22.

[0018] Embodiments of the spacer fabric 24 have a weight that ranges between 1 ounces/yard² and 6 ounces/yard². Alternatively, the spacer fabric 24 may have a weight that ranges between 3 ounces/yard² and 5 ounces/yard². In another alternative embodiment, the spacer fabric 24 may have a weight that is about 4 ounces/yard². Embodiments of the spacer fabric 24 may have a thickness (d) measured as the distance between the outer surface 20 and the inner surface 22 that ranges from about 1/16 of an inch to around 1/2 of an inch. An alternative embodiment of the spacer fabric 24 may have a thickness (d) that ranges from about 1/16 of an inch to around 1/4 of an inch. Alternatively, the spacer fabric 24 may have a thickness (d) that is about 1/8 of an inch.

[0019] Embodiments of the reusable underpad 10 utilizing a spacer fabric 24 advantageously separate the user from the liquid captured by the intermediate layer 14, with the intermediate yarns 26 providing a space through which air can move thereby promoting healthier skin.

[0020] The intermediate layer 14 of the present reusable underpad 10 is formed from a microfiber fabric that includes adsorbent microfiber yarns, absorbent microfiber yarns, or microfiber yarns that are both adsorbent and absorbent. In one embodiment, about 90% to 100% of the yarns in the intermediate layer 14 are microfiber yarns. In embodiments of the underpad 10, the fabric is warp knit, weft knit, or woven with microfiber yarns. Exemplary microfiber yarns include mono- component microfiber yarns, bi-component microfiber yarns, and tri-component microfiber yarns. The preferred microfiber yarn includes polyester and nylon, with about 60 % by weight to 80 % by weight of the microfiber yarn being polyester and the balance being nylon. In one embodiment, the microfiber yarn is about 70% by weight polyester and about 30% by weight nylon.

[0021] In the embodiment illustrated in FIG. 1, the intermediate layer 14 is a knit or woven pile fabric that includes looped pile, cut pile, or combinations of looped pile and cut pile. Preferably, the pile fabric is a looped pile fabric. In one embodiment, the intermediate layer 14 is a warp knit looped pile fabric. In another embodiment and with reference to FIG. 3, the loops 35 (and/or cut loops - not shown) of the pile 34 may project from only one face 32 of the base fabric 37 of the intermediate layer 14. However, in alternative embodiments (not shown), the loops and/or cut loops of the pile may project from both faces of the base fabric of the intermediate layer 14. With further reference to FIGS. 1 and 3, the pile 34 of the fabric 37 may be arranged in patterns such as rows 36, 38, squares, or other patterns. The patterns are formed from areas of fabric 37 having pile 34 (such as row 36) being separated from other areas of fabric 37 having pile 34 (such as row 38) by an area of fabric 37 lacking pile 40. The areas of fabric lacking pile 40 form channels 42, 44 that assist with the distribution of liquid from the face layer 12 into the intermediate layer 14.

[0022] In the illustrated embodiment, the pile 34 of the intermediate layer 14 contacts the inner surface 22 of the face layer 12. Without being bound to a particular theory, arranging the pile 34 of the intermediate layer 14 to contact the inner surface 22 of the face layer 12 promotes the adsorption and/or absorption of liquid by the intermediate layer 14.

[0023] Embodiments of the intermediate layer 14 have a weight that ranges from about 200 g/m² (gsm) to about 800 gsm. In another embodiment, the intermediate layer 14 has a weight that ranges from about 200 gsm to about 400 gsm. In another embodiment, the intermediate layer 14 has a weight that ranges from about 250 gsm to about 300 gsm. In another embodiment, the intermediate layer 14 has a weight that is about 280 gsm. The microfiber fabric intermediate layer 14 is capable of holding a very large weight of liquid compared to the weight of the fabric. In the preferred embodiment, the underpad has a single intermediate layer 14 that has the capacity to contain at least about 500 milliliters of liquid per 1000 square inches. An embodiment of the reusable underpad includes one intermediate layer 14. An alternative embodiment of the reusable underpad may include more than one intermediate layer 14 stacked one on top of the other.

[0024] The microfiber fabric intermediate layer 14 improves the speed and efficiency of moisture transfer through the spacer fabric 24 of the face layer 12 as compared to conventional polyester and rayon nonwoven absorbent layers. An additional advantage of the microfiber fabric intermediate layer 14 is that the microfiber fabric can actively pull liquid through the face layer 12, which improves the function of the spacer fabric 24. [0025] With reference again to FIGS. 1 and 2, the barrier layer 16 of the present reusable underpad 10 is formed from a substantially liquid impermeable material. In one example, a material is considered to be substantially liquid impermeable if it has at least about 50 cm of hydrostatic resistance as determined by AATCC 127. In another embodiment, the barrier layer 16 is substantially liquid impermeable while also being substantially air permeable to allow gases and vapors to escape through the barrier layer 16. Utilizing a substantially air permeable barrier layer 16 assists with drying the reusable underpad 10 during laundering. In one example, a material is considered to be substantially air permeable if it allows for an airflow of at least cubic feet air/min/square foot fabric. Embodiments of the barrier layer 16 may be formed from a woven or knit fabric 46, such as a polyester fabric, that includes a coating 48, such as a silicon or a urethane coating, on its inner surface 50 such as to render the material substantially liquid impermeable and substantially air permeable. In a preferred embodiment, the fabric is woven. Alternative embodiments of the barrier layer 16 may be coated with vinyl. The coating 48 may be applied to a surface of the fabric 37, such as the inner surface 50, by routine methods.

[0026] In the illustrated embodiment, the face layer 12, the intermediate layer 14, and the barrier layer 16 each have a size and shape that are generally the same such that the outer edges of each of the three layers generally overlie one another. The three layers 12, 14, 16 can be stitched to one another with a stitch 52 that is applied around the outer edges of the three layers 12, 14, 16.

[0027] During use, the reusable underpad 10 is placed on a surface, such as the surface of a bed or chair, with the barrier layer 16 contacting the surface being protected and the outer surface 20 of the face layer 12 facing up. A subject, such as a patient who might release a bodily fluid, is positioned on the face layer 12 of the reusable underpad 10 such that any released liquids will contact the face layer 12 and be absorbed and/or adsorbed into the intermediate layer 14 while the barrier layer 16 prevents the liquid from soaking through to the bed or chair. A soiled underpad 10 may be laundered and dried by means and method s known in the art for use agai n, as explained above.

[0028] While the present invention has been illustrated by the description of one or more em bodiments thereof, and while the embodiments have been described in considerable detail, they are not intended to restrict or in any way limit the scope of the appended claims to such deta il . For example, the face layer 12, the intermediate layer 14, or both layers 12, 14 may be treated with one or more chemical agents that en hance or improve the liquid hand ling properties of the layer 12, 14. Additional advantages and modifications will readily appear to those skilled in the art. The invention in its broader aspects is therefore not limited to the specific details, representative apparatus and method and il lustrative examples shown and described. Accordingly, departures may be made from such details without departing from the scope or spirit of the general inventive concept.

Claims

WHAT IS CLAIMED IS:

1. A reusable underpad for contai ning liquids comprising:

a liquid permeable face layer, an intermediate layer, and a substantially liq uid im permeable barrier layer, wherein the intermediate layer is intermediate to the face layer a nd the barrier layer and is com prised of mi crofiber fabric that is capable of adsorbing, absorbing, or both adsorbing and absorbing a l iquid .

2. The underpad of claim 1 wherein the intermed iate layer is a microfiber fabric knit or woven from microfi ber yarns.

3. The u nderpad of claim 2 wherein the microfiber yarns are a bi-component microfiber yarn.

4. The underpad of claim 2 wherein the intermed iate layer includes piles projecting from at least one surface.

5. The u nderpad of claim 4 wherein the piles are loop piles.

6. The underpad of claim 4 wherein the piles project from on ly one surface of the intermediate layer.

7. The underpad of claim 4 wherein the piles projecting from the at least one surface of the intermediate layer contact an inner surface of the face layer.

8. The underpad of claim 4 wherein the piles are a rranged in a pattern formed by groups of piles being sepa rated from other groups of pi les by an a rea of fabric lacking piles, wherein the area of fabric lacking piles form a channel.

9. The u nderpad of claim 8 wherein groups of piles are arranged into rows or sq uares that are sepa rated from one another by channels formed by areas of fabric lacking piles.

10. The underpad of claim 1 wherein the intermed iate layer is a fabric having a weight ra nging from about 200 gsm to about 800 gsm .

11. The underpad of claim 1 wherein the intermediate layer is a fabric havi ng a weight rangi ng from about 200 gsm to about 400 gsm.

12. The underpad of claim 1 wherein the i ntermediate layer is a fabric havi ng a weight ranging from about 250 gsm to about 300 gsm .

13. The underpad of claim 1 wherein the intermed iate layer is a fabric having a weight of about 280 gsm .

14. The underpad of claim 1 wherein the bi-component microfi ber yarns include polyester and nylon and the polyester ranges from 60% by weight to about 80% by weight of the yarn with the balance being nylon.

15. The underpad of claim 1 wherein the bi-component microfiber yarns includes about 70% by weight polyeste r and about 30% by weight nylon.

16. The underpad of claim 1 wherein the face layer is comprised of a th ree dimensiona l spacer fabric.

17. The underpad of claim 16 wherein the spacer fabric is formed from a 100% polyester multifila ment yarn.

18. The u nderpad of claim 16 wherein the spacer fabric is formed from a 1005 polyeste r monofilament yarn.

19. The u nderpad of claim 16 wherein the spacer fabric has an outer surface with a relatively fine mesh and an inner surface with a larger mesh as com pared to the outer surface.

20. The u nderpad of claim 16 wherei n the spacer fabric has a weight in a range from about 3 ounces/yard² to about 5 ou nces/yard².

21. The underpad of claim 16 wherein the spacer fabric has a weight of about 4 ounces/yard².

22. The underpad of claim 16 wherein the spacer fabric has a thickness in a range from about 1/16 of an inch to about 1/2 of an inch.

23. The underpad of claim 16 wherei n the spacer fabric has a thickness of about 1/8 of an inch.

24. The underpad of claim 1 wherein the barrier layer is fu rther su bstantial ly air permea ble.

25. The underpad of claim 1 wherein the ba rrier layer incl udes a woven or knit fabric with a coating layer.

26. The underpad of claim 23 wherein the fabric is formed from polyester yarns.

27. The underpad of claim 23 wherein the coating layer is selected from silicone, urethane, or vinyl.