Floor underlayment having self-sealing vapor barrier

Abstract

A flooring material having a textile pad substructure with a density of greater than 10 pounds per cubic foot is provided. The textile pad has reinforcement and binding fibers. The binding fibers are thermoplastic and are used to bind the reinforcement fibers together. The pad is created by heating and compressing a fibrous textile batt so that it has a density of greater than 13 pounds per cubic foot.

Description

FIELD

The present invention relates generally to a textile pad for laminate floor underlayment. More specifically, the invention relates to a flooring system which uses a textile pad under laminate wood flooring material to improve acoustic and thermal insulation properties as well as crack resistance.

BACKGROUND

Textile pads are widely used in flooring applications. A pad is desirable when wood flooring is applied over a subflooring. These pads used in flooring applications serve multiple purposes. They may absorb impact, such as from persons walking on the flooring. They may provide sound deadening, and may provide insulating properties against heat transfer. Pads also may accommodate roughness, unevenness, or other flaws in the subflooring, and may provide a barrier against moisture and dirt. Finally, pads may lessen impact stresses on the flooring to lengthen the life of the flooring and make the flooring appear to be more durable and of a higher quality.

In the related art, textile pads are not used under ceramic flooring. This is because a pad would have to be relatively thin so as to not cause any unevenness in transition areas (i.e., areas of flooring type transition, such as in doorways, etc.). Furthermore, ceramic tiles traditionally must be placed on a solid floor substructure to prevent cracking of the tile or the adhesive or tile grout.

What is needed, therefore, are improvements in methods and apparatus for forming textile pads for a laminate floor underlayment as well as a textile pad which can be used under a ceramic tile floor.

SUMMARY

A flooring material having a textile pad substructure with a density of greater than 13 pounds per cubic foot is provided according to a first aspect of the invention. The insulative textile flooring pad has reinforcement fibers and binding fibers. The binding fibers are thermoplastic fibers which are melted to couple the binding fibers and reinforcement fibers together. The binding fibers are selected from the group of polyethylene, polyester, polypropylene, and mixtures thereof.

Further, a flooring structure is disclosed. The flooring structure has a subfloor, a surface layer, and an insulative pad disposed between the subfloor and the surface layer. The insulative pad has binder and reinforcement fibers distributed uniformly and randomly within a first plane. The binder fibers are meltable at a predetermined temperature to couple the binding fibers to the reinforcement fibers.

Further disclosed is a floor underlayment for disposal under a floor surface. The floor underlayment has less than 20% thermoplastic binder fibers and more than 80% reinforcement fibers. The floor underlayment has a first surface disposed adjacent to the floor surface and has a density of greater than 13.3 pounds per cubic foot.

Further disclosed is an apparatus for forming a plurality of textile pads from a textile batt according to another aspect of the invention. The apparatus comprises a pair of feed rollers for receiving a textile batt, a splitting knife downstream of the feed rollers that is capable of splitting the textile batt to produce partial thickness textile batts, adhesive appliers positioned downstream of the splitting knife that are capable of applying an adhesive to an outer surface of each of the partial thickness textile batts, multi-layer vapor barrier supply positioned downstream of the adhesive appliers that is capable of supplying vapor barrier material that contacts the outer surfaces of the partial thickness textile batts, and pressure rollers positioned downstream of the vapor barrier supply that are capable of partially compressing the partial thickness textile batts to bond to the vapor barrier adhesive.

Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.

DRAWINGS

The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein:

FIG. 1 shows a side or cross-sectional view of a portion of a textile batt;

FIG. 2 shows two textile batts bonded to multi-layer vapor barriers to form the two textile pads;

FIG. 3 shows an apparatus for forming two textile pads from the textile batt;

FIG. 4 shows a flooring structuring according to one embodiment of the invention;

FIG. 5 shows as vapor barrier layup structure according to the present teachings; and

FIG. 6 represents a floor structure having a fastener passed through the textile pad.

DETAILED DESCRIPTION

The following description of the preferred embodiments is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.

FIG. 1 shows a side or cross-sectional view of an insulative floor batt 100, according to the teachings of the present invention. The insulative floor batt 100 is manufactured from any of a wide variety of textile compositions comprising, for example, polyester, nylon, acrylic, cotton, polypropylene, denim etc., or combinations thereof, including both natural and man-made fibers. Randomly distributed textile and binder fibers having lengths between 1/16 inch to 1.5 inches and a denier of between 5 and 12 are used to form a textile batt 100, which is processed to form the insulative floor pad 90.

FIG. 2 shows one embodiment of the present invention where two textile pads 200′ and 200 are bonded to multi-layer vapor barrier layers 206′ and 206 to form the two textile underlayment pads 210′ and 210. The resulting pads may be used as a laminate flooring underlayment or as a pad for other types of flooring or for other purposes. The textile batt 100 is first heated in an oven 110 and compressed to form an insulative floor pad 90. Optionally, the insulative floor pad 90 can be split into two partial pads 200′ and 200, and each pad bonded to a multi-layer vapor barrier layer 206′ and 206.

Each partial thickness pad 200′ and 200 may be of equal thickness (i.e., the textile insulative floor pad is split in half), or may be of unequal thickness'. The present invention is capable of forming a partial thickness batt of about 1/16 of an inch or greater. The starting insulative floor pad 90 may be split longitudinally to provide two, three or more partial thickness batts.

The thermoplastic binder fibers and reinforcement fibers are laid randomly yet consistently in x-y-z axes. The reinforcement fibers are generally bound together by heating the binder fibers above their glass transition temperature. Typically, less than about 20% by weight binder fiber is used, and preferably about 15% binder fiber is used to form the insulative floor pad 90.

Thermoplastic binder fibers are provided having a weight of less than 0.2 pounds per square foot and, more particularly, preferably about 0.1875 pounds per square foot. The remaining reinforcement fiber is greater than 0.8 pounds per square foot, and preferably 1.0625 pounds per square foot. The binder fibers are preferably a mixture of thermoplastic polymers which consist of polyethylene/polyester or polypropylene/polyester or combinations thereof.

The insulative floor pad 90 is formed by heating the textile batt 100 in the oven 110 to a temperature greater than about 350° F. and, more preferably, to a temperature of about 362° F. Such heating causes the binder fibers to melt and couple to the non-binder fibers, thus causing fibers to adhere to each other and solidify during cooling. Upon cooling, the binder fibers solidify and function to couple the non-binder reinforcement fibers together as well as function as reinforcement themselves.

The insulative textile batt 100 is compressed to form the insulative floor pad 90 so it has a density of greater than about 10 pounds per cubic foot. For underlayment floor systems, the insulative floor pad 90 preferably has a density of greater than about 10 pounds per cubic foot and, more preferably, about 13.3 pounds per cubic foot with a thickness of about ⅛ inch. For insulative floor pad 90 used under ceramic tile, the density is greater than about 15 pounds per cubic foot and, more preferably, about 18.9 pounds per cubic foot.

The sound insulating properties of the material as tested under ASTME90-97, ASTME413-87 provide that the insulative floor pad 90 preferably has a compression resistance at 25% of the original thickness of greater than about 20 psi and preferably about 23.2 psi, at 30% of greater than about 35.0 psi and preferably about 37.0 psi, and at 50% of greater than about 180 psi and preferably about 219 psi. The compression set at a compression of 25% of the original thickness is less than 20% and preferably about 18.8%, and the tensile strength is between about 60 and 80 pounds and, most preferably, about 78.4 pounds.

FIG. 3 shows an apparatus 300 for forming two textile underlayment pads 210 and 210′ from the insulative floor pad 90. The apparatus includes a splitting machine 114, a pair of tension rollers 118, adhesive appliers 123, a pair of vapor barrier supply rollers 126 providing the vapor barrier layers 206, a pair of pressure rollers 129, and a pair of take-up rollers 132.

The feed rollers 104 receive the insulative floor pad 90 and pass it to the splitting knife 107, where the insulative floor pad 90 is split into the two partial thickness batts or pads 200′ and 200. The thickness of each partial thickness pad is determined by both the thickness of the insulative floor pad 90 and the position of the splitting knife 107 in relation to the feed rollers 104. When the splitting knife 107 is substantially centered between the feed rollers 104, the insulative floor pad 90 will be split into two substantially equal partial thickness pads.

In the present invention, it has been found that the insulative floor pad 90 may be controllably and accurately split if the feed rollers 104 are positioned within a predetermined distance from the splitting knife 107. The distance is important because of the compressible and pliable nature of the insulative floor pad 90. In the preferred embodiment, the predetermined distance is from about zero to about two millimeters.

In a preferred embodiment using the Mercier Turner splitting machine 114, the splitting machine 114 is modified by adjusting the feed rollers 104 to a position as close as possible to the splitting knife 107, and removing feed guides so that the splitting knife 107 may be moved closer to the feed rollers than would be possible with the feed guides still in place. In addition, the splitting machine 114 is modified by changing the feed rollers 104 from a serrated surface type with multiple sections to a smooth surface type of a single piece construction.

The tension rollers 118 maintain a predetermined amount of tension on the two partial thickness pads 200′ and 200.

The adhesive appliers 123 are downstream of the tension rollers 118 and apply adhesive to outer surfaces of the two partial thickness batts. In a preferred embodiment, the adhesive appliers 123 spray a layer of adhesive onto the two partial thickness batts. Alternatively, the adhesive appliers 123 may apply the adhesive directly such as, for example, with wipers or brushes.

The adhesive is preferably a high viscosity, low melting point adhesive that is applied hot and forms a bond as it cools (i.e., a “hot melt” adhesive). Such adhesives are available from H.B. Fuller, from Swift Adhesive, and from Western Adhesive (the Western Adhesive product is sold under the product name of RHM542.) Alternatively, any other adhesive capable of bonding the textile batt to the multi-layer vapor barrier may be used.

The pair of vapor barrier supply rollers 126 are also located downstream of the tension rollers 118 and serve to supply a vapor barrier layer 206′ and 206 to each of the two partial thickness pads 200′ and 200.

The multi-layer vapor barrier preferably is a plastic sheet material, typically about ½ to about 1 mil in thickness. The multi-layer vapor barrier, as the name implies, prevents the travel of vapor (usually water vapor) through the textile pads 210′ or 210.

The pair of pressure rollers 129 are downstream of the adhesive appliers 123 and the vapor supply rollers 126. The pair of pressure rollers 129 bring together the two partial thickness pads 200′ and 200 and the two vapor barrier layers 206′ and 206 to form the two textile underlayment pads 210′ and 210. The pair of pressure rollers 129 heat and partially compress the batts during the bonding of the adhesive to form the two textile underlayment pads 210′ and 210.

In the preferred embodiment, the pressure rollers 129 apply about 400 psi (pounds per square inch) of pressure to the two partial thickness textile pads 200′ and 200 and to the multi-layer vapor barrier layers 206′ and 206. In addition, the pressure rollers 129 are maintained at a temperature of about 200 degrees Fahrenheit. The heating partially softens or breaks down the multi-layer vapor barrier to make it pliable and to aid in penetration of the multi-layer vapor barrier by the adhesive.

Downstream of the pressure rollers 129 is a pair of take-up rollers 132. The pair of take-up rollers 132 may be used to roll up the finished textile underlayment pads 210′ and 210. The finished textile underlayment pads 210′ and 210 may be used as a floor underlayment, a laminate floor underlayment, as part of a paint drop cloth, etc.

FIG. 4 discloses a floor structure 212 according to the present invention. The floor is formed of a subfloor 214, a surface layer 216, and the insulative floor pad 90 which is disposed between said subfloor 214 and surface layer 216. The insulative floor pad 90 is formed by the binder and reinforcement fibers which are distributed substantially random in a first plane. The binder fibers are meltable at a predetermined temperature to couple the binding fibers to the reinforcement fibers.

The floor surface layer 216 can be wood, a wood based laminate, or polymer. The binder fibers are thermoplastic and are preferably selected from the group containing polyethylene, polyester, polypropylene, and mixtures thereof.

As shown in FIG. 5, the multi-layer vapor barrier layer 206 is a multilayer coextruded film which is configured to sealably engage a nail or a fastener which has been driven through the multi-layer vapor barrier. Optionally, the multi-layer vapor barrier is an opaque seven layer coextruded film. The film 206 is formed of a pair of outer polyamide (nylon) skin layers, which has a naturally high dyne level. Dyne level is defined as a measurement of surface tension. The higher the dyne level, the better the adhesion to an object piercing the multi-layer vapor barrier 206. Disposed between the polyamide skin layers 230 are the internal layers of LLDPE polyethylene 232. Disposed between the nylon skin layers 230 and the internal layer or layers 232 or LLDPE polyethylene is a tie or an adhesive material 236 that binds two dissimilar materials together, for example nylon and LLDPE. Linear low-density polyethylene (LLDPE) is a substantially linear polymer (polyethylene), with significant numbers of short branches, commonly made by copolymerization of ethylene with longer-chain olefins. Linear low-density polyethylene differs structurally from conventional low-density polyethylene (LDPE) because of the absence of long chain branching. In general, LLDPE is produced at lower temperatures and pressures by copolymerization of ethylene and such higher alpha-olefins as butene, hexene, or octene.

Alternatively, the multi-layer vapor barrier 206 can be a laminate having a layup such as Nylon/LLDPE /Nylon/LLDPE and Tie/LLDPE and Tie/LLDPE and Tie/LLDPE and color concentrate. The most common stretch wrap material is linear low-density polyethylene or LLDPE, which is produced by copolymerization of ethylene with alpha-olefins, the most common of which are butene, hexene and octene. The use of higher alpha-olefins (hexene or octene) gives rise to enhanced stretch film characteristics, particularly in respect of elongation at break and puncture resistance. Other types of polyethylene and PVC can also be used. Many films have about 500% stretch at break but are only stretched to about 100-300% in use. Once stretched, the elastic recovery is used to keep the load tight around the piecing member.

As shown in FIG. 6, the laminate construction allows the film to sealingly engage the outside surface of a piecing nail or screw 238. Upon engagement with the nail 238, the multi-layer vapor barrier elastically deforms along the length of the nail to form a seal 240. Upon piercing of all of the laminate layers, the material elastically relaxes, compressing the formed hole around the piercing nail, thus forming a seal which reduces the transport of water vapor through the multi-layer vapor barrier 206.

The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention.

Claims

1. A floor structure comprising: an insulative pad disposed adjacent to a laminate floor covering, the insulative pad having an interlocked fibrous web layer having a compression resistance at a compression of 25% of the original thickness of greater than about 20 psi;a multilayer film vapor barrier fixably coupled to the insulative pad, wherein the multilayer film vapor barrier comprises a pair of external polyamide skin layers, disposed between the polyamide skin layers is an internal layer of linear low-density polyethylene; anda fastener pierced through the insulative pad and the multilayer film vapor barrier, forming a hole defined in the multilayer film vapor barrier, wherein the multilayer film vapor barrier elastically relaxes, compressing the hole through the multilayer film vapor barrier around the fastener, and thereby forming a seal between the fastener and the multilayer film vapor barrier, which reduces transport of water vapor through the multilayer film vapor barrier.

2. The floor structure according to claim 1, wherein the multilayer film vapor barrier comprises a polyamide skin layer adjacent a linear low-density polyethylene layer.

3. The floor structure according to claim 1, wherein the laminate floor covering comprises wood.

4. The floor structure according to claim 1, wherein the fastener is a nail.

5. The floor structure according to claim 1, wherein the insulative pad is about 3/32 inch thick.

6. The floor structure according to claim 1, wherein the insulative pad has a compression resistance at 50% of the original thickness of greater than about 180 psi.

7. The floor structure according to claim 1, further comprising an adhesive layer disposed between the insulative pad and the vapor barrier.

8. A wood based laminate floor structure comprising: an insulative pad disposed adjacent to a wood based laminate, said insulative pad consisting of an interlocked fibrous web;a multilayer coextruded film vapor barrier fixably coupled to the insulative pad, wherein the multilayer coextruded film vapor barrier is formed of a pair of external skin layers, disposed between the skin layers is at least one internal layer of linear low-density polyethylene; anda fastener pierced through the fibrous web and the multilayer coextruded film vapor barrier forming a hole defined in the multilayer coextruded film vapor barrier, wherein the multilayer coextruded film vapor barrier elastically relaxes, compressing the hole through the multilayer coextruded film vapor barrier around the fastener, and thereby forming a seal between the fastener and the multilayer coextruded film vapor barrier which reduces transport of water vapor through the multilayer coextruded film vapor barrier.

9. The floor structure according to claim 8, wherein the external skin layers are polyamide skin layers, and the at least one internal layer of linear low-density polyethylene includes a pair of linear low-density polyethylene layers disposed between the polyamide skin layers.

10. The floor structure according to claim 8, further comprising an adhesive layer between at least one of the external skin layers and the at least one internal layer of linear low-density polyethylene.

11. The floor structure according to claim 8, wherein the insulative pad is about 3/32 inch thick.

12. The floor structure according to claim 8, wherein the insulative pad has a compression resistance at 50% of the original thickness of greater than about 180 psi.

13. The floor structure according to claim 8, further comprising an adhesive layer disposed between the insulative pad and the vapor barrier.

14. The floor structure according to claim 8, wherein the multilayer coextruded film vapor barrier defines an aperture defined around and in contact with the fastener.

15. A floor structure disposed over a subfloor and fastened to the subfloor with a fastener comprising: a floor surface layer;an insulative pad disposed adjacent to the floor surface layer, said insulative pad consisting of an interlocked fibrous web; anda film vapor barrier fixably coupled to the insulative pad, the film vapor barrier has a pair of polyamide skin layers and at least one low-density polyethylene layer disposed between the pair of polyamide skin layers, wherein the fastener is pierced through the vapor barrier forming a hole defined in the pair of polyamide skin layers and the at least one low-density polyethylene layer, wherein at least a portion of the film vapor barrier elastically relaxes, compressing the hole through the vapor barrier around the fastener, and thereby forming a seal between the fastener.

16. The floor structure according to claim 15, further comprising an adhesive disposed between the polyamide skin layers and the at least one low-density polyethylene layer.

17. The floor structure according to claim 15, wherein the insulative pad has a compression resistance at 50% of the original thickness of greater than about 180 psi.

18. The floor structure according to claim 15, wherein the at least one low-density polyethylene layer includes multiple low-density polyethylene layers.

19. The floor structure according to claim 15, wherein the at least one low-density polyethylene layer includes at least one linear low-density polyethylene layer.

20. The floor structure according to claim 15, wherein the fastener extends through the insulative pad and the film vapor barrier.