U.S. patent application number 11/291633 was filed with the patent office on 2006-07-06 for recycled energy absorbing underlayment and moisture barrier for hard flooring system.
Invention is credited to Norman Manning, Steven E. Ogle.
Application Number | 20060144012 11/291633 |
Document ID | / |
Family ID | 36638781 |
Filed Date | 2006-07-06 |
United States Patent
Application |
20060144012 |
Kind Code |
A1 |
Manning; Norman ; et
al. |
July 6, 2006 |
Recycled energy absorbing underlayment and moisture barrier for
hard flooring system
Abstract
A flooring underlayment comprising a plurality of recycled
fibers formed into a nonwoven fiber batt, and a resin intermixed
with the recycled fibers in the nonwoven fiber batt, the resin
bonding the recycled fibers together. The invention includes a
flooring underlayment comprising a plurality of recycled fibers
formed into a nonwoven fiber batt, wherein the nonwoven fiber batt
is formed using a method selected from the group comprising resin
bonding, thermal bonding, mechanical bonding, and combinations
thereof. The invention includes a nonwoven fiber batt comprising a
blend of recycled fibers and binder fibers formed into a nonwoven
fiber batt, and a resin intermixed with the recycled fibers and the
binder fibers in the nonwoven fiber batt, wherein the resin and the
binder fibers bond the recycled fibers and the binder fibers in the
nonwoven fiber batt together.
Inventors: |
Manning; Norman;
(Hendersonville, TN) ; Ogle; Steven E.;
(Murfreesboro, TN) |
Correspondence
Address: |
CONLEY ROSE, P.C.
5700 GRANITE PARKWAY, SUITE 330
PLANO
TX
75024
US
|
Family ID: |
36638781 |
Appl. No.: |
11/291633 |
Filed: |
December 1, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60632315 |
Dec 1, 2004 |
|
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Current U.S.
Class: |
52/782.1 |
Current CPC
Class: |
E04F 15/182 20130101;
D04H 1/48 20130101; E04F 15/18 20130101; E04C 2/16 20130101; B32B
5/02 20130101; B32B 5/022 20130101; B32B 2307/7265 20130101; E04F
15/04 20130101; B32B 2266/08 20130101; B32B 2471/00 20130101; D04H
1/43835 20200501; B32B 2307/7246 20130101; B32B 2260/021 20130101;
B32B 5/245 20130101; Y10T 156/10 20150115; B32B 2307/102 20130101;
E04F 15/186 20130101; B32B 2260/046 20130101; E04F 15/203 20130101;
B32B 27/12 20130101 |
Class at
Publication: |
052/782.1 |
International
Class: |
E04C 2/00 20060101
E04C002/00 |
Claims
1. A flooring underlayment comprising: a plurality of recycled
fibers formed into a nonwoven fiber batt; and a resin intermixed
with the recycled fibers in the nonwoven fiber batt, the resin
bonding the recycled fibers together.
2. The flooring underlayment of claim 1 wherein the recycled fibers
are shoddy fibers.
3. The flooring underlayment of claim 1: wherein the flooring
underlayment comprises an upper surface and a lower surface; and
wherein the flooring underlayment further comprises a moisture
barrier attached to the upper surface or the lower surface of the
nonwoven fiber batt.
4. The flooring underlayment of claim 3 wherein the moisture
barrier comprises: a flap that extends past the edge of the
nonwoven fiber batt.
5. The flooring underlayment of claim 3 wherein the moisture
barrier is closed cell foam.
6. The flooring underlayment of claim 3 wherein the nonwoven fiber
batt has a ratio of basis weight to thickness greater than about 2
to 1.
7. The flooring underlayment of claim 3 wherein the moisture
barrier is attached to the nonwoven fiber batt without an
adhesive.
8. The flooring underlayment of claim 3 wherein the nonwoven fiber
batt has a density at most about 10 pounds per cubic foot.
9. The flooring underlayment of claim 3 wherein the flooring
underlayment is attached to a flooring layer.
10. A flooring system comprising: a subfloor; a flooring layer
positioned above the subfloor; and the flooring underlayment of
claim 1 positioned between the subfloor and the flooring layer.
11. A flooring underlayment comprising a plurality of recycled
fibers formed into a nonwoven fiber batt, wherein the nonwoven
fiber batt is formed using a method selected from the group
comprising: resin bonding, thermal bonding, mechanical bonding, and
combinations thereof.
12. The flooring underlayment of claim 11: wherein the flooring
underlayment comprises an upper surface and a lower surface; and
wherein the flooring underlayment further comprises a moisture
barrier attached to the upper surface or the lower surface of the
nonwoven fiber batt.
13. The flooring underlayment of claim 12 wherein the nonwoven
fiber batt has a density at most about 10 pounds per cubic
foot.
14. The flooring underlayment of claim 13 wherein the recycled
fibers are shoddy fibers.
15. A flooring system comprising: a subfloor; a flooring layer
positioned above the subfloor; and the flooring underlayment of
claim 14 positioned between the subfloor and the flooring
layer.
16. A nonwoven fiber batt comprising: a blend of recycled fibers
and binder fibers formed into a nonwoven fiber batt; and a resin
intermixed with the recycled fibers and the binder fibers in the
nonwoven fiber batt; wherein the resin and the binder fibers bond
the recycled fibers and the binder fibers in the nonwoven fiber
batt together.
17. The nonwoven fiber batt of claim 16: wherein the nonwoven fiber
batt comprises an upper surface and a lower surface; and wherein
the nonwoven fiber batt further comprises a moisture barrier
attached to the upper surface or the lower surface of the nonwoven
fiber batt.
18. The nonwoven fiber batt of claim 16 wherein the nonwoven fiber
batt has a density at most about 10 pounds per cubic foot.
19. The nonwoven fiber batt of claim 16 wherein the binder fibers
have a weight per unit length at most about 5 denier.
20. A flooring system comprising: a subfloor; a flooring layer
positioned above the subfloor; and the nonwoven fiber batt of claim
16 positioned between the subfloor and the flooring layer.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This Application claims priority from U.S. Provisional
Patent Application Ser. No. 60/632,315 filed Dec. 1, 2004, which is
hereby incorporated by reference as if reproduced in its
entirety.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable.
REFERENCE TO A MICROFICHE APPENDIX
[0003] Not applicable.
FIELD OF THE INVENTION
[0004] The present disclosure relates to flooring systems and, more
particularly, to a hard flooring system that contains an energy
absorbing layer manufactured from recycled materials and a moisture
barrier.
BACKGROUND
[0005] Typically, a subfloor is either a slab of concrete or one or
more sheets of plywood supported by a combination of joists, beams,
posts and, in multiple-story buildings, bearing walls. Broadly
speaking, a flooring layer is comprised of the various materials
which, when installed above the subfloor, collectively form the
flooring for a building or other structure. Many times, an
underlayment may be installed between the subfloor and the flooring
layer. The primary types of flooring layers used in structures are
"soft" flooring layers and "hard" flooring layers. As its name
suggests, soft flooring is soft, quiet underfoot, and tends to
yield upon application of a force thereto. Hard flooring, on the
other hand, is hard and thus durable and easy to maintain. However,
hard flooring also tends to be relatively noisy, cold, and hard
underfoot.
[0006] Most hard flooring, particularly wood and laminate flooring,
has an underlayment installed between the subfloor and the
flooring, which acts as a moisture barrier, an energy absorber, and
a leveler. Moisture barriers are important because they prevent the
migration of moisture from the subfloor into the flooring. Moisture
barriers are essential for slab foundations and basements because
the moisture frequently seeps through the concrete subfloor into
the wood or laminate flooring, causing the wood to warp or the
laminate flooring to delaminate. If the flooring is soft flooring,
such as carpet, moisture causes mildew or microbial growth in the
carpet. Underlayment is also important in hard flooring because the
underlayment absorbs some of the sound or "echo" created by a
person walking on the hard floor. Underlayment also creates a more
level surface for the flooring by smoothing high points (peaks),
low points (valleys), and other irregularities in the subfloor so
that the flooring rests on a more level surface.
[0007] A wide variety of underlayments are used in conjunction with
flooring. For example, a thin, continuous film of polymer, such as
polyethylene or vinyl, may be installed over the subfloor to
provide a moisture barrier. Oftentimes, a polymeric open cell foam
layer is positioned over the polymer film to provide a degree of
cushioning to the flooring placed above it. The polymer film and
open cell foam layer may be laminated to one another or may be
discrete components installed one over the other. Alternatively, a
solid sheet of polymer having some cushioning characteristics, for
example, a slightly polymerized vinyl chloride polymer, can
function as both a moisture barrier and a cushion between the
subfloor and the flooring. Another suitable underlayment is a
laminate composite formed of a moisture impervious vinyl,
polyethylene, or polyester film attached to latex or vinyl foam.
Other flooring underlayments include nonwoven batts of polyester,
nylon, or polypropylene with a moisture barrier attached to one
side of the batt.
[0008] One of the goals of flooring manufacturers is to reduce the
time and complexity of installing the flooring. While this goal is
important for flooring that is installed by professional
installers, such as carpet, this goal is essential for flooring
that is installed by consumers, such as laminate flooring, because
consumers will often base their purchase decisions on the
complexity and time required to install the flooring as well as the
price of the flooring. These consumer needs have led to an increase
in the number of flooring systems that have tongue-and-groove,
click-together, or other connection mechanisms on a plurality of
their edges so that the flooring is quick and easy to install.
However, with all of these advances in flooring installation, the
consumer still has to install the underlayment in the conventional
manner, which often includes laying down sheets of the underlayment
on the subfloor prior to installing the flooring. Therefore, a need
exists for a method of simplifying the process of installing a
flooring underlayment while simultaneously reducing the time
required to install the underlayment.
[0009] One of the ongoing concerns of many underlayment
manufacturers is the need to reduce manufacturing costs. Lowered
manufacturing costs result in lower product costs, which make the
manufactured product more appealing to the consumers. Underlayment
consumers, particularly large retail outlets and flooring
installers, are constantly seeking the lowest price on flooring
underlayment and frequently change suppliers in order to save a few
cents per square foot of underlayment. Thus, it is in the
manufacturers' best interest to produce flooring underlayment for
the lowest possible price. As the cost of upgrading manufacturing
equipment to improve efficiency can be prohibitive, most
manufacturers seek to lower production costs by using less
expensive materials to manufacture the underlayment. Consequently,
what is needed is a flooring underlayment material that is less
expensive than the existing flooring underlayment material, which
will allow manufacturers to produce and sell a flooring
underlayment that is less expensive than existing flooring
underlayment.
[0010] Another ongoing concern for many manufacturers is the
consumer's perception of the manufacturer. Manufacturers who use
recycled materials to manufacture their product are perceived as
environmentally friendly or "green", a trait preferred by consumers
who are environmentally conscious. Consumers who are
environmentally conscious are willing to pay a premium for goods
that contain recycled materials. Recycled materials are generally
made from previously used or waste materials, and thus are
relatively inexpensive. Because recycled materials are both
cost-effective and consumer-preferable, a need exists for a
flooring underlayment that utilizes recycled materials.
SUMMARY
[0011] In one aspect, the invention includes a flooring
underlayment comprising: a plurality of recycled fibers formed into
a nonwoven fiber batt; and a resin intermixed with the recycled
fibers in the nonwoven fiber batt, the resin bonding the recycled
fibers together. In an embodiment, the recycled fibers are shoddy
fibers. In another embodiment, the flooring underlayment comprises
an upper surface and a lower surface; and the flooring underlayment
further comprises a moisture barrier attached to the upper surface
or the lower surface of the nonwoven fiber batt. The moisture
barrier may comprise a flap that extends past the edge of the
nonwoven fiber batt and/or the moisture barrier may be closed cell
foam. In yet another embodiment, the nonwoven fiber batt has a
ratio of basis weight to thickness greater than about 2 to 1. The
moisture barrier may be attached to the nonwoven fiber batt without
an adhesive. Variously, the nonwoven fiber batt has a density at
most about 10 pounds per cubic foot, and/or the flooring
underlayment is attached to a flooring layer. The invention
includes a flooring system comprising: a subfloor; a flooring layer
positioned above the subfloor; and the flooring underlayment
positioned between the subfloor and the flooring layer.
[0012] In another aspect, the invention includes a flooring
underlayment comprising a plurality of recycled fibers formed into
a nonwoven fiber batt, wherein the nonwoven fiber batt is formed
using a method selected from the group comprising: resin bonding,
thermal bonding, mechanical bonding, and combinations thereof. In
an embodiment, the flooring underlayment comprises an upper surface
and a lower surface and the flooring underlayment further comprises
a moisture barrier attached to the upper surface or the lower
surface of the nonwoven fiber batt. In another embodiment, the
nonwoven fiber batt has a density at most about 10 pounds per cubic
foot. The recycled fibers may be shoddy fibers. The invention
includes a flooring system comprising: a subfloor; a flooring layer
positioned above the subfloor; and the flooring underlayment
positioned between the subfloor and the flooring layer.
[0013] In yet another aspect, the invention includes a nonwoven
fiber batt comprising: a blend of recycled fibers and binder fibers
formed into a nonwoven fiber batt; and a resin intermixed with the
recycled fibers and the binder fibers in the nonwoven fiber batt;
wherein the resin and the binder fibers bond the recycled fibers
and the binder fibers in the nonwoven fiber batt together. In an
embodiment, the nonwoven fiber batt comprises an upper surface and
a lower surface; and the nonwoven fiber batt further comprises a
moisture barrier attached to the upper surface or the lower surface
of the nonwoven fiber batt. Variously, the nonwoven fiber batt has
a density at most about 10 pounds per cubic foot, and/or the binder
fibers have a weight per unit length at most about 5 denier. The
invention includes a flooring system comprising: a subfloor; a
flooring layer positioned above the subfloor; and the nonwoven
fiber batt of claim 16 positioned between the subfloor and the
flooring layer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] For a more complete understanding of the present invention,
and for further details and advantages thereof, reference is now
made to the accompanying drawings, in which:
[0015] FIG. 1 is a perspective view of an embodiment of the
Recycled Energy Absorbing Underlayment and Moisture Barrier for
Hard Flooring System;
[0016] FIG. 2 is a perspective view an embodiment of the Recycled
Energy Absorbing Underlayment and Moisture Barrier for Hard
Flooring System installed under the hard flooring layer;
[0017] FIG. 3 is a perspective view of an embodiment of the
Recycled Energy Absorbing Underlayment and Moisture Barrier for
Hard Flooring System attached to the hard flooring layer;
[0018] FIG. 4 is a block diagram of an embodiment of the method of
manufacturing the fiber batt embodiment of the Recycled Energy
Absorbing Underlayment and Moisture Barrier for Hard Flooring
System;
[0019] FIG. 5 is a plan view of an embodiment of an apparatus for
manufacturing the fiber batt embodiment of the Recycled Energy
Absorbing Underlayment and Moisture Barrier for Hard Flooring
System in accordance with the method of FIG. 4;
[0020] FIG. 6A is a side view of an embodiment of a thermal bonding
apparatus used in forming the shoddy batt embodiment of the
Recycled Energy Absorbing Underlayment and Moisture Barrier for
Hard Flooring System in accordance with the method of FIG. 4;
[0021] FIG. 6B is a side view of an embodiment of an alternative
thermal bonding apparatus used in forming the shoddy batt
embodiment of the Recycled Energy Absorbing Underlayment and
Moisture Barrier for Hard Flooring System in accordance with the
method of FIG. 4;
[0022] FIG. 7 is a block diagram of an embodiment of the method of
manufacturing the bonded foam embodiment of the Recycled Energy
Absorbing Underlayment and Moisture Barrier for Hard Flooring
System;
[0023] FIG. 8 is a side view of an embodiment of a mixing tank used
in forming the bonded foam embodiment of the Recycled Energy
Absorbing Underlayment and Moisture Barrier for Hard Flooring
System;
[0024] FIG. 9 is a side view of an embodiment of an apparatus for
compressing and steaming the bonded foam embodiment of the Recycled
Energy Absorbing Underlayment and Moisture Barrier for Hard
Flooring System;
[0025] FIG. 10 is a side view of an embodiment of an apparatus for
peeling the bonded foam embodiment of the Recycled Energy Absorbing
Underlayment and Moisture Barrier for Hard Flooring System;
[0026] FIG. 11 is a side view of an embodiment of an alternative
apparatus for compressing and steaming the bonded foam embodiment
of the Recycled Energy Absorbing Underlayment and Moisture Barrier
for Hard Flooring System;
[0027] FIG. 12 is a side view of an embodiment of an apparatus for
laminating the film embodiment of the moisture barrier onto the
energy absorbing layer in accordance with the methods of FIGS. 4
and 7; and
[0028] FIG. 13 is a side view of an embodiment of the apparatus for
laminating the closed cell foam embodiment of the moisture barrier
onto the energy absorbing layer in accordance with the methods of
FIGS. 4 and 7.
DETAILED DESCRIPTION
[0029] The Recycled Energy Absorbing Underlayment and Moisture
Barrier for Hard Flooring System will now be described in greater
detail. As seen in FIG. 1, the underlayment 50 generally comprises
a moisture barrier 54 laminated onto an energy absorbing layer 52
made of recycled materials. The energy absorbing layer 52 may be a
nonwoven fiber batt made from recycled fibers, such as shoddy
materials or bonded foam. Shoddy materials are recycled fibers from
clothing, bedding, fabric, and other natural and synthetic
materials. Alternatively, the shoddy materials may be a specific
type of recycled fiber, such as polyester or polypropylene from the
manufacturing of bedding components or cotton waste from the yarn
spinning process. The shoddy material is generally cleaned and
shredded to form a homogeneous blend of fibers prior to being
formed into a nonwoven batt. Bonded foam pads are made from a
plurality of foam pieces that are attached together. The foam
pieces are generally collected from waste, trimmings, and recycled
carpet pads. The foam pieces are preferably polyurethane foam, but
may also be other materials such as latex foam, polyvinyl chloride
(PVC) foam, or any other polymeric foam.
[0030] The moisture barrier 54 is a thin layer of material that is
attached or otherwise laminated onto the energy absorbing layer 52.
The moisture barrier 54 is made of a material that is impervious to
liquid moisture and moisture vapor. Alternatively, the moisture
barrier 54 may be permeable with respect to moisture vapor, but
impervious to liquid moisture. Such moisture barriers 54 are
advantageous because they discourage the transmission of liquid
moisture across the underlayment yet allow the underlayment to
"breathe." Further in the alternative, the moisture barrier 54 may
contain one hydrophobic side and one hydrophilic side. Such
moisture barriers 54 encourage the migration of moisture in one
direction, but not the other direction. The moisture barrier 54 is
typically a polymeric film, such as polyethylene or ethylene vinyl
acetate (EVA) copolymer. An example of a suitable film is 150 gauge
low density polyethylene film weighing 35 grams per square meter,
available from numerous manufacturers including Dow.RTM. and
DuPont.RTM.. Alternatively, the moisture barrier 54 may be a layer
of closed cell foam, such as a styrene butadiene rubber (SBR),
latex, or PVC foam. By definition, closed cell foam has too few
interconnecting cells to allow the transmission of bulk fluids
through the foam. The formulation of a typical closed cell foam is
disclosed in U.S. patent application Ser. No. 10/306,271 to Brodeur
et al., entitled "Moisture Barrier and Energy Absorbing Cushion,"
incorporated herein by reference as if reproduced in its entirety.
A number of other moisture barriers 54 are commercially available,
any one of which may be suitable for the underlayment 50.
[0031] While the underlayment 50 is described in conjunction with
hard flooring layer, it is contemplated that the underlayment 50
can be used as an underlayment for any type of flooring. As used
herein, the term "flooring" refers to any type of flooring product
that utilizes an underlayment. The term flooring includes soft
flooring, such as carpet and rugs, and hard flooring. As used
herein, the term "hard flooring" refers to rigid flooring products
that utilize and underlayment such as ceramic tile, linoleum,
vinyl, wood flooring, and laminate flooring. Hard flooring layers
typically require an underlayment with a moisture barrier that
keeps moisture from migrating from the subfloor into the hard
flooring layer. Moisture in the hard flooring layer is not
preferred because the moisture tends to warp, rot, or delaminate
the hard flooring. As used herein, the term "laminate flooring"
describes any flooring product that contains various layers
attached or otherwise laminated together and includes laminated
pressboard, paper, or wood particles, and the like. The term
"laminate flooring" also includes ceramic tile or other flooring
attached to laminated pressboard, paper, or wood particles, and the
like. Examples of laminate flooring are the products sold under the
names PERGO.TM. laminate flooring and EDGE.TM. precision tile.
[0032] The orientation of the underlayment (i.e. with the moisture
barrier on the upper or lower side of the energy absorbing layer)
when installed under the hard flooring layer is an important aspect
of installing the underlayment. For example, if the underlayment is
placed moisture barrier side down, then the moisture barrier
prevents the migration of moisture from the subfloor into the
energy absorbing layer and the hard flooring layer. This
application is typically well suited for basement and slab
foundation applications. Alternatively, if the underlayment is
placed moisture barrier side up, the moisture barrier prevents the
migration of moisture from the hard flooring layer into the energy
absorbing layer. This application is typically well suited for
upper floor applications. However, the circumstances associated
with individual applications will dictate the particular
orientation of the underlayment (i.e. whether the moisture barrier
side is placed face-up or face-down) when the underlayment is
installed under the flooring.
[0033] In an alternative embodiment, the underlayment can be
configured with the moisture barrier on both sides of the energy
absorbing layer. This embodiment enjoys the benefits of both
embodiments described above: a moisture barrier between the
subfloor and the energy absorbing layer, and a moisture barrier
between the energy absorbing layer and the hard flooring layer.
This embodiment is preferable when the energy absorbing layer has a
high percentage of absorbent materials because the absorbent
materials readily absorb moisture into the energy absorbing layer
and can promote the growth of mildew, mold, fungus, and/or
microbes. It is also contemplated the underlayment can contain an
antimicrobial additive to discourage the growth of mildew, mold,
fungus, and microbes. Two examples of such antimicrobial,
antifungal, or similar additives are the Sanitized.TM. and
Actigard.TM. product lines available from Sanitized AG of Burgdorf,
Switzerland. The incorporation of an antimicrobial, antifungal, or
similar additive to the underlayment is described in U.S. patent
application Ser. No. 10/840,309 to Gilder entitled "Anti-Microbial
Carpet Underlay and Method of Making", which is incorporated herein
by reference as if reproduced in its entirety.
[0034] As a further alternative embodiment, the underlayment can be
configured without a moisture barrier laminated onto the energy
absorbing layer. Manufacturing the energy absorbing layer without a
moisture barrier lowers the production cost of the underlayment.
The moisture barrier may be unnecessary for applications where
discouraging moisture migration is not an issue. In dry climates,
such as the southwest United States, moisture is not as problematic
as in coastal and other humid regions. Thus, the need for a
moisture barrier is not as great in these areas. In addition,
multi-story homes may not need a moisture barrier on the upper
floors because moisture migration from the subfloor is limited to
the bottom floor of the residence. Thus, there may not be a need
for a moisture barrier on the upper floors. Consequently, in some
applications the elimination of the moisture barrier from the
manufacturing process can reduce the production costs and make the
underlayment less expensive and thus more appealing to
consumers.
[0035] In a further alternative embodiment, the underlayment can be
manufactured with a flap that is an extension of the moisture
barrier past at least one edge of the underlayment (see flap 56 in
FIG. 2). Preferably, the flap consists of about 4 inches of
moisture barrier extending past two adjacent edges of the
underlayment. This embodiment allows the flap of a previously
installed piece of underlayment to be positioned underneath the
moisture barrier on a newly installed and similarly oriented piece
of underlayment, thereby creating an overlapping moisture barrier
at the seam between the two pieces of underlayment. The overlapping
moisture barrier is beneficial because there is an opportunity for
moisture to circumvent the moisture barrier at the seam between two
pieces of underlayment. An overlapping moisture barrier is
additional assurance that the moisture barrier will discourage the
migration of moisture into the flooring. If the moisture barrier is
on the upper surface of the underlayment, the flap may be secured
in place with tape. If the moisture barrier is on the lower surface
of the underlayment, the weight of the newly installed piece of
underlayment is sufficient to hold the flap in place. However, the
newly installed piece of underlayment can be secured to the
existing piece of underlayment with a piece of tape or other
apparatus, if desired.
[0036] The installation of the underlayment will now be described
in greater detail. FIG. 2 is a perspective view of a corner of a
room where the underlayment 50 is installed between the subfloor 62
and the hard flooring layer 60. As previously stated, the
underlayment 50 may be installed with either the moisture barrier
side facing up or the moisture barrier side facing down. In FIG. 2,
the underlayment 50 is installed with the moisture barrier side
facing down. The embodiment of the underlayment 50 in FIG. 2
contains the flap 56, discussed previously. The flap of the
right-most piece of underlayment 50, which is covered by the
left-most piece of underlayment 50, is indicated by the dashed line
in FIG. 2. When installing a piece of the underlayment 50, the
installer places the piece of underlayment 50 directly adjacent to
the existing underlayment 50. If the underlayment 50 contains a
flap 56, the new piece of underlayment 50 is placed on top of the
flap 56 of the existing piece of underlayment 50. The pieces of
underlayment 50 are secured in place with a piece of tape 58. After
the underlayment 50 has been installed, the hard flooring layer 60
is installed on top of the underlayment 50. The long seams of the
hard flooring layer 60 may run parallel, perpendicular, diagonally,
or any other orientation with respect to the long seams of the
underlayment 50.
[0037] In an alternative embodiment of the installation process, an
additional piece of moisture barrier (not shown) may be installed
under the outside edge of the underlayment 50 where the subfloor 62
meets the walls 63, such that the additional piece of moisture
barrier is simultaneously under the horizontal underlayment 50 and
extends up the walls 63 of the room (i.e. in the vertical plane).
If the underlayment 50 is configured with the flap 56, the flap 56
can be used as the additional piece of moisture barrier by simply
bending the flap 56 so that the flap 56 is vertically oriented
against the wall 63. The additional piece of moisture barrier
adjacent to the walls 63 may be concealed using trim (not shown)
after the hard flooring layer 60 has been installed over the
underlayment 50. This embodiment allows the moisture barrier 54 to
partially extend up the walls 63 of the room, thereby protecting
the edges of the hard flooring 60 from moisture.
[0038] As yet another alternative embodiment of the present
invention, the underlayment 50 can be attached to the underside of
the hard flooring layer 60 as illustrated in FIG. 3. Attaching the
underlayment 50 to the bottom of the hard flooring layer 60 is
preferable because it combines the separate steps of installing the
underlayment and installing the hard flooring layer 60 on top of
the underlayment 50. By utilizing the embodiment illustrated in
FIG. 3, the user can install the underlayment 50 and the hard
flooring layer 60 in substantially less time than separately
installing the underlayment 50 and the hard flooring layer 60. If
desired, the embodiment shown in FIG. 3 may be configured with a
piece of tape or moisture barrier (similar to flap 56 in FIG. 2)
that extends past the edge of the underlayment 50. The piece of
tape or moisture barrier is utilized much the same way as flap 56
in FIG. 2 to create a more secure moisture barrier seal at the seam
where two pieces of underlayment 50 are installed next to each
other.
[0039] One method for making the Recycled Energy Absorbing
Underlayment and Moisture Barrier for Hard Flooring System will now
be described in greater detail. As seen in FIG. 4, the method for
making the nonwoven fiber batt embodiment of the Recycled Energy
Absorbing Underlayment and Moisture Barrier for Hard Flooring
System 70 generally comprises: blending the fibers 72, forming the
fibers into a web 74, coating the web with a resin 76, needle
punching the web 78, compressing the web 80, heating the web to
form a batt 82, cooling the batt 84, trimming the batt 86, and
laminating the moisture barrier onto the batt 90. If it is
desirable to attach the underlayment 50 to the hard flooring layer
60 as seen in FIG. 3, then the method 70 further comprises the step
of adhering or otherwise laminating the underlayment onto the hard
flooring layer 92. Each of these steps is described in greater
detail below.
[0040] Referring now to FIG. 5, a schematic top plan view of the
general processing line 110 for constructing an underlayment in
accordance with the teachings of the present invention will now be
described in greater detail. The general processing line performs
72 through 86 in method 70. As may now be seen, the recycled fibers
are blended together per 72 in method 70 in a fiber blender 112 and
conveyed by conveyor pipes 114 to a web forming machine or, in this
example, three machines 116, 117, and 118. The recycled fibers are
preferably shoddy fibers, but may be recycled natural fibers such
as cotton or wool, recycled synthetic fibers such as polyester or
polypropylene, or a mixture of recycled natural and synthetic
fibers. A suitable web forming apparatus is a garnett machine. An
air laying machine, known in the trade as a Rando webber, or any
other suitable apparatus can also be used to form a web structure.
Garnett machines 116, 117, and 118 card the blended fibers into a
web per 74 in method 70, the web having a desired width and
delivers the web to a cross lapper, or in this example three
cross-lappers 116', 117', and 118' to cross-lap the web onto a slat
conveyor 120 which is moving in the machine direction.
Cross-lappers 116', 117', and 118' reciprocate back and forth in
the cross direction from one side of conveyor 120 to the other side
to form the web having multiple thicknesses in a progressive
overlapping relationship. The number of layers that make up the web
is determined by the speed of the conveyor 120 in relation to the
speed at which successive layers of the web are layered on top of
each other and the number of cross-lappers 116', 117', and 118'.
Thus, the number of single layers which make up the web can be
increased by slowing the relative speed of the conveyor 120 in
relation to the speed at which cross layers are layered, by
increasing the number of cross-lappers 116', 117', and 118', or
both. Conversely, a fewer number of single layers can be achieved
by increasing the relative speed of conveyor 120 to the speed of
laying the cross layers, by decreasing the number of cross-lappers
116', 117', and 118', or both. In the present invention, the number
of single layers which make up the web of fibers varies depending
on the desired characteristics of the underlayment of the present
invention. As a result, the relative speed of the conveyor 120 to
the speed at which cross layers are layered and the number of
cross-lappers 116', 117', and 118' for forming the web may vary
accordingly.
[0041] A heat curable resin is then applied to the web by resin
applicator 122 per 76 in method 70. While there are a variety of
techniques suitable for applying resins onto the web, generally
liquid resin is sprayed onto the web or froth resin is extruded
onto the web. Resins suitable for the present invention are curable
by heat and can be any of a variety of compositions. Generally, the
resin is comprised of polyvinyl acetate, but may also be a
polymeric composition such as vinylidene chloride copolymer, latex,
acrylic, or any other chemical compound. An example of a suitable
resin is the SARAN 506 resin sold by the Dow Chemical Company.
Additionally, the resin can contain antimicrobial, antifungal, or
hydrophobic additives that further enhance the properties of the
energy absorbing layer 52.
[0042] Further describing the application of liquid resin, as the
web moves along a conveyor in the machine direction, the resin is
sprayed onto the web from one or more spray heads that move in a
transverse or cross direction to substantially coat the web.
Alternatively, froth resin can be extruded onto the web using a
knife or other means. The web can also be fed through or dipped
into a resin bath. The applied resin is crushed into the web for
saturation therethrough by nip rollers disposed along the
transverse direction of the conveyor to apply pressure to the
surface of the batt. Alternatively, the resin is crushed into the
web by vacuum pressure applied through the batt.
[0043] The web then moves to a needle loom 124 where the web is
needle-punched per 78 in method 70 to increase the density of the
web. The needle loom is a device that bonds a nonwoven web by
mechanically entangling the fibers within the web. The needle loom
contains a needle board that contains a plurality of
downwardly-facing barbed needles arranged in a non-aligned pattern.
The barbs on the needles are arranged such that they capture fibers
when the needle is pressed into the web, but do not capture any
fibers when the needle is removed from the web. A variety of
suitable needles are offered by the Foster Needle Company,
Incorporated. The use of the needle loom in the present invention
provides mechanical compression of the web prior to vacuum and/or
mechanical compression along with the heating that occurs in
housing 130. It is within the scope of the invention to forego the
needle punching described herein if adequate compression can be
obtained by vacuum and/or mechanical compression. Likewise, it is
within the scope of the invention to forego the vacuum and/or
mechanical compression if adequate compression can be obtained by
needle punching.
[0044] The conveyor 120 then transports the web to housing 130 for
mechanical and/or vacuum compression per 80 of method 70 and
heating per 82 of method 70. While there are a variety of resin
bonding methods which are suitable for the purposes contemplated
herein, one such method comprises using vacuum pressure applied
through perforations (not shown) in first and second counter
rotating drums 140 and 142 positioned in a central portion of the
housing 130. The first and second counter rotating drums 140 and
142 heat the web to the extent necessary to cure the resin in the
web, typically 225-275.degree. F. for three to five minutes.
Alternatively, the web may instead move through an oven by
substantially parallel perforated or mesh wire aprons that
mechanically compress the batt and simultaneously cure the
resin.
[0045] As the web exits the housing 130, the web is compressed and
cooled per 84 in method 70 by a pair of substantially parallel wire
mesh aprons 170, only one of which is visible in FIG. 5. The aprons
170 are mounted for parallel movement relative to each other to
facilitate adjustment for a wide range of web thicknesses. The web
can be cooled slowly through exposure to ambient temperature air
or, in the alternative, ambient temperature air can be forced
through the perforations of one apron 170, through the web and
through the perforations of the other apron 170 to cool the web and
set it in its compressed state. The web is maintained in its
compressed form upon cooling since the solidification of the resin
bonds the fibers together in that state.
[0046] While there are a variety of resin bonding methods which are
suitable for the present invention, one such method, illustrated in
FIG. 6A, comprises holding the web by vacuum pressure applied
through perforations of first and second counter-rotating drums and
heating the web so that the resin in the batt cures to the extent
necessary to fuse together the fibers in the web. Alternatively,
the web moves through an oven by substantially parallel perforated
or mesh wire aprons to cure the resin.
[0047] As may be seen in FIG. 6A, the aforementioned vacuum
pressure method may be implemented using counter-rotating drums
140, 142 having perforations 141, 143, respectively, which are
positioned in a central portion of a housing 130. The housing 130
also comprises an air circulation chamber 132 and a furnace 134 in
an upper portion and a lower portion, respectively, thereof. The
drum 140 is positioned adjacent an inlet 144 though which the web
is fed. The web is delivered from the blending and web-forming
processes described herein by means of an infeed apron 146. A
suction fan 150 is positioned in communication with the interior of
the drum 140. The lower portion of the circumference of the drum
140 is shielded by a baffle 151 positioned inside the drum 140 such
that the suction-creating air flow is forced to enter the drum 140
through the perforations 141, which are proximate the upper portion
of the drum 140, as the drum 140 rotates.
[0048] The drum 142 is downstream from the drum 140 in the housing
130. The drums 140, 142 can be mounted for lateral sliding movement
relative to one another to facilitate adjustment for a wide range
of batt thicknesses (not shown). The drum 142 includes a suction
fan 152 that is positioned in communication with the interior of
the drum 142. The upper portion of the circumference of the drum
142 is shielded by a baffle 153 positioned inside the drum 142 so
that the suction-creating air flow is forced to enter the drum 142
through the perforations 143, which are proximate the lower portion
of drum 142, as the drum 142 rotates.
[0049] The nonwoven web is held in vacuum pressure as it moves from
the upper portion of the rotating drum 140 to the lower portion of
the counter rotating drum 142. The furnace 134 heats the air in the
housing 130 as it flows from the perforations 141, 143 to the
interior of the drums 140, 142, respectively, to cure the resin in
the web to the extent necessary to bind together the fibers in the
web.
[0050] Referring to FIG. 6B, in an alternative resin bonding
process, the web enters housing 130' by a pair of substantially
parallel perforated or mesh wire aprons 160, 162. The housing 130'
comprises an oven 134' that heats the web to cure the resin to the
extent necessary to bind the fibers in the web together.
[0051] Collectively referring back to FIGS. 4, 5, 6A and 6B, the
web is compressed and cooled per 84 of method 70 as it exits from
the housing 130 or 130' by a pair of substantially parallel first
and second perforated or wire mesh aprons 170 and 172. The aprons
170 and 172 are mounted for parallel movement relative to each
other to facilitate adjustment for a wide range of web thicknesses
(not shown). The web can be cooled slowly through exposure to
ambient temperature air or, alternatively, ambient temperature air
can be forced through the perforations of one apron, through the
web and through the perforations of the other apron to cool the web
and set it in its compressed state. The web is maintained in its
compressed form upon cooling since the resin bonds the fibers
together in the compressed state. The cooled web (which, after
completion of the bonding, compression and cooling, is referred to
as a batt) moves into cutting zone 180 where the lateral edges of
the batt are trimmed per 86 to a finished width. The batt is then
cut transversely to a desired length.
[0052] It is contemplated that thermal bonding may be used to bond
the batt together in lieu of the resin bonding method described
herein. Thermal bonding uses low-melt binder fibers to bind the
fibers together. Low-melt binding fibers do not actually melt as
the term is generally understood; instead, the low-melt binder
fibers become sticky or tacky when heated to a certain temperature.
If the fiber batt is to be thermally bonded, the low-melt binder
fibers are blended with the recycled fibers to make a homogeneous
fiber blend of recycled fibers and low-melt binder fibers. The
fiber blend is then carded into a web as described above. It is not
necessary to apply a resin to the web if the web is to be thermally
bonded although in many instances it may be desirable to do so to
obtain the advantageous features of the resin described below. The
web is then needle punched, if a compression is desired prior to
simultaneous heat and compression. The web is then sent to a
compression and heating apparatus, such as those illustrated in
FIGS. 6A and 6B, where the heat melts the low-melt binder fibers.
The batt is then cooled and trimmed in the same way that the resin
embodiment of the batt was cooled and trimmed.
[0053] In the thermal bonded embodiment, the fiber batt is
preferably formed from a homogeneous blend of binder fibers and
recycled fibers. The binder fibers can be either natural or
synthetic fibers. The binder fibers may also be mono-component
binder fibers or bi-component binder fibers. While the homogeneous
mixture of recycled fibers and binder fibers can be any of a number
of suitable fiber blends, for purposes of illustrating the process
and the blend, the mixture is comprised of binder finders in an
amount sufficient for binding the fibers of the blend together upon
application of heat at the appropriate temperature to melt the
binder fibers. In one example, the binder fibers are in the range
of about 5 percent to about 95 percent by total volume of the
blend. Preferably, the binder finders are present in the range of
about 10 percent to about 15 percent for a high-loft batt and in
the range of about 15 percent to about 40 percent for a densified
batt, as those characteristics are discussed below. The recycled
fibers in the remaining blend volume ranges anywhere from about 5
percent to about 95 percent. Preferably, the recycled finders are
present in the range of about 85 percent to about 90 percent for a
high-loft batt and in the range of about 60 percent to about 85
percent for a densified batt, as those characteristics are
discussed below. Blends having other percentages of binder fibers
and recycled fibers are also within the scope of the invention.
[0054] The weight per unit length of the binder fibers is also a
consideration. While coarse binder fibers, e.g. those binder fibers
having a weight per unit length of at least about 5 denier, are
suitable for the purposes described herein, preferably the binder
fibers are fine binder fibers. It is believed that a batt made of
the fine binder fibers contains less porosity due to their ability
to fill smaller void spaces within the binder fiber batt. By
filling more of the void spaces than the coarse binder fibers, the
fine binder fibers give the binder fiber batt better acoustical
properties than the binder fiber batt having the coarse binder
fibers. In various embodiments, the weight per unit length of the
binder fibers in the binder fiber batt is at most about 5 denier,
at most about 3 denier, or at most about 1 denier.
[0055] It is also contemplated that mechanical bonding may be used
to bond the batt together in lieu of the resin bonding or thermal
bonding methods described herein. Mechanical bonding is the process
of bonding the nonwoven batt together without the use of resins,
adhesives, or heat. Examples of mechanical bonding methods are
needle punching, hydro entanglement, and clustering. Needle
punching is the previously described method of entangling fibers
using barbed needles. Hydro entanglement uses streams of high
pressure water to entangle the fibers of the nonwoven web.
Clustering is the mechanical entanglement of fibers during the batt
forming process. Clustering frequently uses crimped fibers or
fibers that otherwise have a complex shape. It is also contemplated
that the fiber batt may be manufactured using different
combinations of resin bonding, mechanical bonding, and/or thermal
bonding.
[0056] The use of resin in the batt is advantageous for many
reasons. First, resin-bonded batts are less porous than
mechanically bonded or thermally bonded batts. More specifically,
the resin is able to permeate through the batt more thoroughly and
effectively than fibers, such as recycled fibers or binder fibers,
due to its liquid form. The decreased porosity makes the fiber batt
less water permeable, gives the batt better acoustical insulating
properties, and makes it easier to attach various items, such as
the moisture barrier or a floor covering, to the surface of the
batt. In fact, depending on the specific level of water and/or
vapor permeability sought, it is possible to eliminate the need for
the moisture barrier by applying a sufficient amount to resin to
the fiber batt.
[0057] In the embodiment utilizing a nonwoven fiber batt as the
energy absorbing layer 52, the basis weight, density, and thickness
of the underlayment are determined by, among other factors, the
process of compressing the batt as it is cooled. The ratio of batt
density to batt thickness generally dictates whether the
underlayment is a high loft batt or a densified batt. For purposes
herein, a densified energy absorbing layer has a ratio of basis
weight (in ounces) per square foot to thickness (in inches) greater
than approximately 2 to 1. Thus, a densified underlayment would
have a density greater than approximately 1.5 pounds per cubic foot
(pcf). Conversely, an underlayment having a ratio of basis weight
to thickness of less than approximately 2 to 1 and a density less
than 1.5 pcf are defined herein as high loft batts.
[0058] The expected amount of handling prior to installation should
be a consideration when selecting the density of the fiber batt.
Denser fiber batts provide better acoustical properties than less
dense fiber batts. The acoustical properties of the fiber batt are
important because a person of ordinary skill in the art will
generally want the fiber batt to attenuate as much sound as
possible. However, denser fiber batts are also less flexible than
less dense fiber batts. Flexibility is important because a
preferred feature of the fiber batt is the ability to be rolled up
for storage, transportation, handling, and installation. Thus, when
selecting the density of the fiber batt, a person of ordinary skill
in the art must balance the need for acoustical performance with
the need for flexibility. In various embodiments, a suitable
balance for the density of the fiber batt is between about 1 pcf
and about 10 pcf, between about 2 pcf and about 7 pcf, or between
about 3 pcf and about 5 pcf.
[0059] FIG. 7 depicts a block diagram of the major steps comprising
one embodiment of a method 180 for making a bonded floor covering
underlayment. The method 180 comprises: shredding foam into foam
pieces 182, separately mixing a pre-polymer 183, coating the foam
pieces with the pre-polymer 184, compressing the foam pieces into a
foam log 185, steaming the foam log 186, drying the foam log 187,
coring the foam log 188, peeling the foam log 189 into sheets, and
laminating the moisture barrier onto the sheets 191. If desired,
the sheets may then be adhered or otherwise attached to the hard
flooring layer. Each of these steps is described in greater detail
below.
[0060] Utilizing the bonded foam embodiment, the Recycled Energy
Absorbing Underlayment and Moisture Barrier for Hard Flooring
System begins with foam, which is generally scrap foam trimmings
from a prime foam manufacturer. However, the foam may also be new
foam or recycled foam. The size and shape of the foam is not
important because the foam is shredded into a plurality of smaller
foam pieces. The foam may be polyurethane, latex, polyvinyl
chloride (PVC), or any other polymeric foam of any density. The
foam is generally free of moisture. The foam may contain an
incidental amount of impurities, such as felt, fabric, fibers,
leather, hair, metal, wood, plastic, and so forth. The Recycled
Energy Absorbing Underlayment and Moisture Barrier for Hard
Flooring System includes other foam compositions and should not be
limited to the foam compositions disclosed herein. Preferably, the
foam is polyurethane foam with a density similar to the desired
density of the subsequently produced underlayment. If desired, the
foam may be sorted by type and/or density prior to shredding such
that foam pieces of similar composition and density are used to
make a single foam log. Using foam of similar composition and
density to make a single foam log produces a more uniform density
throughout the foam log, and thus throughout the subsequently
produced underlayment.
[0061] Once the foam for the foam log has been selected, the foam
is placed in a shredding machine for shredding per 182 in method
180. A shredding machine is a machine with a plurality of blades
that cut the foam into smaller pieces of foam. The shredding
machine resembles a household blender. The amount of time that the
foam spends in the shredding machine determines the size of the
shredded pieces of foam. The shredding machine may operate as
either a batch or a continuous process. An example of a suitable
shredding machine is the foam shredder manufactured by the Ormont
Corporation of Paramus, N.J. The foam pieces may be a geometric
shape, such as round or cubic, but are generally an irregular shape
due to the shredding process. The shape of the smaller foam pieces
is generally not important because the foam will conform to the
shape of the mold. The size of the foam pieces should be such that
they are large enough to be easily handled, yet small enough such
that there is not an abundance of empty space between the foam
particles. Preferably, the foam pieces are from about 1/4-inch to
about 3/4-inch in each of length, width, and height dimensions.
[0062] While the foam is being shredded by the shredding machine, a
pre-polymer is mixed in a separate process per 183 in method 180.
One of the chemical compounds in the pre-polymer is isocyanate. The
isocyanate reacts with the polyol (discussed below) and moisture in
the steam (see 186 in method 180) to bind the pieces of foam
together. The isocyanate used in the Recycled Energy Absorbing
Underlayment and Moisture Barrier for Hard Flooring System may be
any type of isocyanate, such as toluene diisocyanate (TDI),
diisocyanatodiphenyl methane (MDI), or blends thereof. Examples of
suitable isocyanates include: m-phenylene diisocyanate, p-phenylene
diisocyanate, polymethylene polyphenyl-isocyanate, 2,4-toluene
diisocyanate, 2,6-toluene diisocyanate, 4,4-diisocyanatodiphenyl
methane, dianisidine diisocyanate, bitolylene diisocyanate,
naphthalene-1,4-diisocyanate, diphenylene-4,4'-diisocyanate,
xylylene-1,4-diisocyanate, xylylene-1,2-diisocyanate,
xylylene-1,3-diisocyanate, bis(4-isocyanatophenyl)-methane,
bis(3-methyl-4-isocyanatophenyl)-methane, 4,4-diphenylpropane
diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate,
methylene-bis-cyclohexylisocyanate, and mixtures thereof. The
Recycled Energy Absorbing Underlayment and Moisture Barrier for
Hard Flooring System includes other isocyanates and should not be
limited to the isocyanates disclosed herein. The preferred
isocyanates are RUBINATE.RTM. 9041 MDI, available from the Huntsman
Corporation of Salt Lake City, Utah, or POLYMERIC MDI 199,
available from the Dow Chemical Corporation of Midland, Mich. The
isocyanate comprises between about 10 weight percent (percent) and
about 90 percent of the total pre-polymer mixture, preferably
between about 20 percent and about 50 percent of the total
pre-polymer mixture. Most preferably, the isocyanate comprises
between about 25 percent and about 40 percent of the total
pre-polymer mixture.
[0063] Another chemical compound in the pre-polymer is polyol. The
polyol used in the Recycled Energy Absorbing Underlayment and
Moisture Barrier for Hard Flooring System may be any type of
polyol, such as diol, triol, tetrol, polyol, or blends thereof.
Examples of suitable polyols include: ethylene glycol, propylene
glycol, butylene glycol, hexanediol, octanediol, neopentyl glycol,
1,4-bishydroxymethyl cyclohexane, 2-methyl-1,3-propane diol,
glycerin, trimethylolethane, hexanetriol, butanetriol, quinol,
polyester, methyl glucoside, triethyleneglycol, tetraethylene
glycol, polyethylene glycol, dipropylene glycol, polypropylene
glycol, diethylene glycol, glycerol, pentaerythritol,
trimethylolpropane, sorbitol, mannitol, dibutylene glycol,
polybutylene glycol, alkylene glycol, oxyalkylene glycol, ethylene
glycol, diethylene glycol, dipropylene glycol, triethylene glycol,
tripropylene glycol, tetraethylene glycol, tetrapropylene glycol,
trimethylene glycol, tetramethylene glycol,
1,4-cyclohexanedimethanol(1,4-bis-hydroxymethylcyclohexane), and
mixtures thereof. The Recycled Energy Absorbing Underlayment and
Moisture Barrier for Hard Flooring System includes other polyols
and should not be limited to the polyols disclosed herein. The
preferred polyol is VORANOL.RTM. 3512A, available from the Dow
Chemical Corporation of Midland, Mich. The polyol comprises between
about 10 percent and about 90 percent of the total pre-polymer
mixture, preferably between about 20 percent and about 50 percent
of the total pre-polymer mixture. Most preferably, the polyol
comprises between about 25 percent and about 40 percent of the
total pre-polymer mixture such that the polyol and isocyanate are
present in the pre-polymer in approximately equal amounts.
[0064] Another chemical compound in the pre-polymer is oil. The oil
lowers the overall viscosity of the pre-polymer solution to
facilitate better mixing and distribution of the components. The
lowered pre-polymer viscosity also allows the pre-polymer to
uniformly coat the foam pieces so that improved bonding occurs. The
oil may be any aromatic or non-aromatic, natural or synthetic oil.
Examples of suitable oils include: naphthenic oil, soybean oil,
vegetable oil, almond oil, castor oil, mineral oil, oiticica oil,
anthracene oil, pine oil, synthetic oil, and mixtures thereof. The
Recycled Energy Absorbing Underlayment and Moisture Barrier for
Hard Flooring System includes other oils and should not be limited
to the oils disclosed herein. The preferred oil is VIPLEX.RTM. 222,
available from the Crowley Chemical Company of New York, N.Y. The
oil comprises between about 10 percent and about 90 percent of the
total pre-polymer mixture, preferably between about 20 percent and
about 50 percent of the total pre-polymer mixture. Most preferably,
the oil comprises between about 25 percent and about 40 percent of
the total pre-polymer mixture such that the oil, polyol, and
isocyanate are present in the pre-polymer in approximately equal
amounts.
[0065] The pre-polymer may also contain a number of other additives
to improve the characteristics of the bonded foam. For example, the
pre-polymer may contain a flame retardant chemical compound, such
as melamine, expandable graphite or dibromoneopentyl glycol, which
improves the flame retardant properties of the bonded foam. The
pre-polymer may also contain an antimicrobial additive, such as
zinc pyrithione, that improves the antimicrobial properties of the
bonded foam, as discussed in the aforementioned patent application.
The pre-polymer may also include an antioxidant, such as butylated
hydroxy toluene, that improve the resistance of the foam to
oxidative-type reactions, such as scorch resulting from high
exothermic temperatures. The pre-polymer may also contain colored
dye, such as blue, green, yellow, orange, red, purple, brown,
black, white, or gray, to distinguish certain bonded foam products
from other bonded foam products. The Recycled Energy Absorbing
Underlayment and Moisture Barrier for Hard Flooring System includes
other additives and should not be limited to the additives
disclosed herein.
[0066] The pre-polymer ingredients are combined and mixed in a
mixer per 183 in method 180. The mixer may be a dynamic mixer or a
static mixer. The mixer may be a batch or a continuous process
mixer. Preferably, the mixer is a tank containing a motorized
paddle-type mixing blade. However, the Recycled Energy Absorbing
Underlayment and Moisture Barrier for Hard Flooring System includes
other types of mixers and should not be limited to the mixers
disclosed herein. The pre-polymer ingredients may be combined all
at once, or they may be added one at a time to the pre-polymer as
it is being mixed. Preferably, the pre-polymer is mixed until there
are about 10 percent free isocyanates available for reacting with
the steam during the steaming process. The mixed pre-polymer has a
viscosity between about 100 and 1,000 centipoises, preferably
between about 400 and 600 centipoises at a temperature between
about 100.degree. F. and about 110.degree. F. Although the time
varies depending on the composition of the pre-polymer, the
pre-polymer is mixed for at least about 1 hour prior to application
of the pre-polymer to the foam pieces. Preferably, the isocyanate,
the polyol, and the oil are mixed together for at least about 4
hours, and then the amine catalyst is added to the other
pre-polymer ingredients and mixed for at least about an additional
two hours.
[0067] After the pre-polymer components (isocyante, polyol, oil,
and any additives) have been suitably mixed, the pre-polymer is
coated onto the foam pieces per 184 in method 180. The coating
machine may be a batch or a continuous coating machine. FIG. 8 is
an illustration of a suitable coating machine 200. The coating
machine 200 comprises a tank 202, an agitator 204, and a
pre-polymer applicator 206. The size and shape of the tank 202 may
be varied to suit the particular application. Similarly, the number
and type of agitators 204 may be varied to suit the particular
application. The process of coating the foam pieces 210 begins by
placing the foam pieces 210 inside the tank 210. The pre-polymer
applicator 206 sprays the pre-polymer 208 onto the foam pieces 210.
While the pre-polymer applicator 206 is spraying the foam pieces
210, the agitator 204 rotates with respect to the tank 202 and
moves the foam pieces 210 around within the tank 202. As the foam
pieces 210 move around in the tank 202, the foam pieces 210 are
substantially coated with the pre-polymer 208. The time required to
substantially coat the foam pieces 210 with the pre-polymer 208
varies depending on the volume and density of the foam pieces 210,
the size of the tank 202, and the number and type of agitators 204,
but is generally between about 0.5 minutes and 15 minutes.
Preferably, the coating process proceeds for between about 1 minute
and about 10 minutes, most preferably between about 1.5 minutes and
about 2.5 minutes. Although the pre-polymer 208 is sprayed onto the
foam pieces 210 in the coating process illustrated in FIG. 8, the
pre-polymer may be applied to the foam pieces by other methods,
such as dipping or roller coating. The Recycled Energy Absorbing
Underlayment and Moisture Barrier for Hard Flooring System includes
other types of coating processes and should not be limited to the
coating process disclosed herein.
[0068] After the foam pieces have been coated with the pre-polymer,
the foam pieces are transferred to a mold for the compression per
185 in method 180. FIG. 9 is an illustration of a typical mold 220
used to compress the foam pieces. The mold 220 comprises a base
229, a cylindrical wall 224, a piston 222, and a steam injection
system 227. The piston 222 is able to move vertically with the wall
224 such that the volume of the cylindrical cavity defined by the
piston 222, the wall 224, and the base 229 can be varied. The
piston 222 is also able to be removed from within the wall 224 and
positioned away from the remainder of the mold 220 to facilitate
easy loading of foam pieces into the cylindrical cavity defined by
the base 229 and the wall 224. The foam pieces are generally
weighed before they are loaded into the mold 224. After the foam
pieces are loaded into the mold 220, the piston 222 compresses the
foam pieces into a foam log 226. The compression ensures complete
contact between the foam pieces in the foam log 226. Because the
weight of the foam pieces is known and volume within the mold 220
can be varied by the piston 222, the density of the foam log 226
can be selected by compressing the foam log 226 to a specific
volume. For example; if the foam pieces weigh 100 pounds and the
desired density of the foam log is 4 pcf, then the piston is
positioned such that the volume of the foam log is 25 cubic feet.
Although a batch-type mold is illustrated in FIG. 9, the foam
pieces may be compressed using other compression methods, such as
the continuous extruder illustrated in FIG. 11. The Recycled Energy
Absorbing Underlayment and Moisture Barrier for Hard Flooring
System includes other types of compressing processes and should not
be limited to the compression process disclosed herein.
[0069] Once the foam pieces are compressed into a foam log 226, the
foam log 226 is steamed to cure the pre-polymer per 186 in method
180. The steam injection system 229 is connected to a steam supply
(not shown) and is able to inject steam 228 through the base 229.
The steam 228 passes through the foam log 226 and any excess steam
exits through perforations in the piston 222. The moisture in the
steam 228 cures the pre-polymer. The steam 228 may be any steam
that is at least about 212.degree. F. and a sufficient pressure to
permeate the foam log 226. Preferably, the temperature of the steam
is between about 220.degree. F. and about the combustion
temperature of the foam (about 1400.degree. F.). The pressure of
the steam is preferably between about 10 pounds per square inch
gauge (psi) and about 100 psi. Most preferably, the temperature of
the steam is between about 246.degree. 0 F. and about 256.degree.
F. and the pressure of the steam is between about 13 psi and 15 psi
for a batch operation and between about 30 psi and about 45 psi for
a continuous operation. The steaming time is dependent on the steam
pressure and the density of the foam log. For a 4 pcf foam log and
using the most preferred steam, the steam time is between about 0.5
minutes and about 3 minutes, preferably about 1.0 minutes and about
1.5 minutes. For an 8 pcf foam log, the steam time is between about
1.5 minutes and about 5 minutes, preferably about 2 minutes and
about 3 minutes. Steam times for foam logs of other densities can
be interpolated or extrapolated from these steam times and steam
data. The wall 224 of the mold 220 is removable with respect to the
base 229 to facilitate easy unloading of a foam log 226 after the
steaming process. The Recycled Energy Absorbing Underlayment and
Moisture Barrier for Hard Flooring System includes other types of
steaming processes and should not be limited to the steaming
process disclosed herein.
[0070] After the steaming 186 is complete, the foam log 226 is
removed from the mold and allowed to dry per 187 in method 180. The
required drying time is dependent on the density of the foam log
226 and the amount of moisture present in the foam log 226. Lower
density foam logs 226 may be sufficiently dry to allow immediate
processing. However, the foam logs 226 are generally set aside to
dry for 12 to 24 hours at ambient temperature and humidity so that
foam logs 226 are sufficiently dry such that the moisture in the
foam log 226 does not affect any of the processing equipment
downstream of the steaming 186. If desired, the drying 187 for the
foam log 226 may be sped up by forcing ambient, heated, and/or
dried air over or through the foam log 226. The Recycled Energy
Absorbing Underlayment and Moisture Barrier for Hard Flooring
System includes other drying processes and should not be limited to
the drying processes disclosed herein.
[0071] After the drying 187 is complete, the foam log 226 is cored
by drilling an aperture through a center axis thereof per 188 in
method 180. A rod is then inserted into the aperture, thereby
enabling the foam log 226 to be handled without damaging the foam.
The foam log 226 is then sent to a suitable peeling machine, such
as peeling machine 230 illustrated in FIG. 10, for peeling per 189
in method 180. The peeling machine 230 comprises a blade 236, a
conveyor 232, and a take-up roll 234. The foam log 226 is rotated
against the blade 236 such that the blade peels off a length of a
flooring underlayment 238 having a desired thickness, T.sub.1, and
formed from the bonded foam. The bonded foam peeled off of the foam
log is uniformly thick and can be used as flooring underlayment
238. As the bonded foam is peeled off of the foam log 226, the foam
log 226 is continuously lowered with respect to the blade 236 such
that the blade 236 constantly peels off a thickness T.sub.1, of
foam from the foam log 226. In other words, as the diameter of the
foam log 226 is reduced, the foam log 226 is lowered so that a
uniform thickness of flooring underlayment 238 is continuously
peeled off of the foam log 226. The flooring underlayment 238 may
also be trimmed to a uniform width. The flooring underlayment 238
travels along the conveyor 232 and is collected on the take-up roll
234 and sent to distributors, wholesalers, and retailers. If
desired, the underlayment may be cut up into shorter lengths on the
take-up roll 234 so that the rolls of flooring underlayment 238 are
lighter and easier to handle.
[0072] As an alternative to the batch compressing and steaming
process described above, the present invention may be utilized in a
continuous compressing and molding process. FIG. 11 illustrates a
continuous extruder 240 used for continuously compressing and
steaming the foam pieces 210 into a continuous foam log 250. The
continuous extruder 240 comprises an upper conveyor 244, a lower
conveyor 242, and a steam injection system 246. The process of
compressing and steaming the foam log 250 begins with the placement
of foam pieces 210 onto the lower conveyor 242. Because the density
of the foam log 250 produced by the continuous extruder 240 depends
on the mass flow rate of the foam pieces 210 through the continuous
extruder 240 as well as the volumetric flow rate of the foam log
250 exiting the extruder, the weight of the foam pieces 210 is
typically measured prior to placing the foam pieces 210 onto the
lower conveyor 242. As the foam pieces 210 travel through the
continuous extruder 240, the foam pieces 210 are compressed by the
upper conveyor 244. Because the upper conveyor 244 and the lower
conveyor 242 travel in the same direction and the foam pieces 210
are continuously entering the continuous extruder 240, the foam
pieces 210 are compressed by the downward traveling upper conveyor
244. The height of the upper conveyor 244 over the lower conveyor
242 is adjustable and the density of the foam log 250 can be
adjusted by raising and lowering the upper conveyor 242 relative to
the lower conveyor 242.
[0073] When the foam log is at a desired density, steam 248 is
injected into the underside of the foam log 250 through
perforations in the lower conveyor 242, with any excess steam
passing through the perforations in the upper conveyor 244. The
continuous extruder 240 is configured such that the residence time
of the foam log 250 in the steaming area of the continuous extruder
240 is equal to the steaming time required in the batch process.
The foam log produced by the continuous extruder 240 is generally
rectangular in cross section and is thus sliced into sheets rather
than peeled in the manner described above.
[0074] After either the nonwoven fiber batt embodiment or the
bonded foam embodiment of the energy absorbing layer 52 is
produced, the moisture barrier 54 is laminated onto the energy
absorbing layer 52 per 90 in method 70 or 191 in method 180 to
create the underlayment 50. In the case where the moisture barrier
54 is a film, FIG. 12 illustrates an apparatus 260 that laminates
the film 274 onto the energy absorbing layer 52. The energy
absorbing layer 52 moves across a conveyer 266 and passes under an
adhesive applicator 262. The adhesive applicator 262 sprays an
adhesive 264 onto the energy absorbing layer 52. Alternatively, the
adhesive applicator 262 could extrude a frothed adhesive onto the
energy absorbing layer 52. The moisture barrier 274 from roll 268
is layered onto the top surface of the energy absorbing layer 52.
Two nip rollers 270 compress the moisture barrier 274 and the
energy absorbing layer 52 together to form the underlayment 50. If
the adhesive 264 needs to be cured, the underlayment 50 can pass
through an oven (not shown) to cure the adhesive. The underlayment
50 is then collected on roller 272 and shipped to wholesalers,
distributors, and/or retailers as needed.
[0075] In the case where the moisture barrier is closed cell foam,
FIG. 13 illustrates an apparatus 300 that laminates a layer of
closed cell foam 304 onto the energy absorbing layer 52. A conveyor
306 carries the energy absorbing layer 52 underneath a foam
applicator 302, which deposits foam 304 on top of the energy
absorbing layer 52. Alternatively, the foam 304 may be sprayed,
roller coated, or otherwise applied to the energy absorbing layer
52, or the energy absorbing layer 52 may be dipped into a vat of
the foam 304. A doctor blade 308 regulates the amount of foam 304
deposited on top of the energy absorbing layer 52. The foam 304 and
energy absorbing layer 52 pass through an oven 310 that cures the
foam 304. The resulting underlayment 50 is collected on a roller
312 and shipped to wholesalers, distributors, and/or retailers as
needed.
[0076] If the energy absorbing layer is 52 is a nonwoven fiber batt
containing recycled synthetic fibers, then an alternative
embodiment of the moisture barrier 54 exists. When the energy
absorbing layer is 52 is a nonwoven fiber batt, the moisture
barrier 54 may be created by calendering one or more surfaces of
the nonwoven fiber batt. Calendering is a process by which one
surface of the batt is modified by passing the batt between a set
of cylindrical drums, one of which is heated. Alternatively, the
batt can be placed on a smooth conveyor belt and passed through an
oven. The heat from the drum or the oven melts the synthetic fibers
in the batt such that they form a thin layer of material similar to
a film. The calendered surface of the batt differs from a layer of
film laminated onto the batt in that the batt and the calendered
surface are the same material, generally polymeric material, but in
fiber and sheet form. The calendered surface of the batt is
generally moisture impervious, but may be vapor permeable,
depending on the specific temperature and calendering apparatus
used. Because the calendered surface of the batt is moisture
impervious, the calendered surface of the batt acts as a moisture
barrier, eliminating the need for any other type of moisture
barrier. Thus, calendering the surface of the batt is advantageous
because it eliminates the need to laminate a moisture barrier onto
the nonwoven fiber batt.
[0077] In an additional alternative embodiment, the energy
absorbing layer 52 and/or the moisture barrier 54 can contain a
scented or deodorizing additive. Scented and deodorizing additives
are advantageous because they improve the smell of the flooring and
can mask or eliminate unwanted odors. Scented and deodorizing
additives are well known in the art, as evidenced by scented and
deodorizing carpet cleaner. It is within the scope of the invention
to include a scented or deodorizing additive in the recycled fiber
blend for the nonwoven fiber batt embodiment of the energy
absorbing layer 52, within the pre-polymer of the bonded foam
embodiment of the energy absorbing layer 52, or within the moisture
barrier 54. Alternatively, the scented or deodorizing additive can
be attached to the energy absorbing layer 52, the moisture barrier
54, or both.
[0078] It is contemplated that methods other than adhesive may be
used to laminate the moisture barrier 54 onto the energy absorbing
layer 52. For example, some moisture barriers 54 become tacky when
heated. If such a moisture barrier 54 were used, the moisture
barrier 54 would be layered onto the energy absorbing layer 52
without the use of an adhesive. The energy absorbing layer 52 and
moisture barrier 54 would then be heated to make the moisture
barrier 54 tacky such that the moisture barrier 54 bonds to the
energy absorbing layer 52. When the underlayment 50 cools, the
moisture barrier 54 would then be attached to the energy absorbing
layer 52 without the use of a separate adhesive. Alternatively, if
the moisture barrier 54 and the energy absorbing layer 52 contain
polymeric and/or thermoplastic materials, the moisture barrier 54
and the energy absorbing layer 52 can be integrally joined by
heating the moisture barrier 54 and the energy absorbing layer 52,
contacting or compressing the moisture barrier 54 and the energy
absorbing layer 52 together, and then cooling the moisture barrier
54 and the energy absorbing layer 52. It is contemplated that any
other bonding method that does not use an adhesive may be used to
laminate the moisture barrier 54 onto the energy absorbing layer
52, thereby forming the underlayment 50.
[0079] If it is desired that the underlayment 50 be attached to the
hard flooring layer 60 per 92 in method 70 or 192 in method 180,
the underlayment 50 is preferably attached to hard flooring layer
60 after the moisture barrier 54 has been attached to the energy
absorbing layer 52. The process of adhering the energy absorbing
layer 52 onto the hard flooring layer 60 is similar to the process
of adhering the moisture barrier 54 onto the energy absorbing layer
52: an adhesive (not shown) is sprayed onto the bottom side of the
hard flooring layer 60 and the underlayment 50 is laminated onto
the bottom side of the hard flooring layer 60. A pair of nip
rollers (not shown) can ensure that the underlayment 50 completely
contacts the hard flooring layer 60. As part of the process of
attaching the underlayment 50 to the hard flooring layer 60, the
hard flooring layer 60 can be inverted so the side that faces up
during the manufacturing process will be the underside of the hard
flooring layer 60 when the hard flooring layer 60 is installed.
This allows gravity to hold the underlayment 50 on the hard
flooring layer 60 until the adhesive takes full effect and bonds
the underlayment 50 onto the hard flooring layer 60.
[0080] Another consideration for the underlayment 50 is the
thickness of the energy absorbing layer 52. While thicker energy
absorbing layers 52 are preferred in some applications, such as
carpet underlayment 50, thinner energy absorbing layers 52 are
preferred in hard flooring layer 60. An example of a energy
absorbing layer 52 suitable for use as an underlayment 50 for hard
flooring layer 60 has a thickness of between about 0.05 inches and
about 0.25 inches, a density of between about 2 pcf and about 20
pcf, and a basis weight of between about 0.5 ounces per square foot
and about 10 ounces per square foot. Preferably, the energy
absorbing layer 52 has a thickness between about 0.1 inches and
about 0.3 inches, a density between about 5 pcf and about 10 pcf,
and a basis weight between about 1 ounce per square foot and about
4 ounces per square foot. Such an underlayment 50 typically comes
in a 3 foot by 60 foot roll and has a roll weight of about 28
pounds.
[0081] There are many advantages to using the underlayment 50 over
prior art underlayments. The underlayment 50 contains recycled
fibers, which lowers the cost of manufacturing the underlayment 50.
With lowered manufacturing costs, the manufacturer can sell the
underlayment 50 to the consumer at a lower cost. The recycled
materials in the underlayment 50 are also appealing to consumers
who prefer recycled materials for environmental reasons. The
underlayment 50 can also be attached to the bottom of hard flooring
60 so that the time and complexity of installing the underlayment
50 and the flooring is reduced. The underlayment 50 also acts a
moisture barrier 54, absorbs the sound of a person walking on the
underlayment 50, and smoothes irregularities in the subfloor.
[0082] While a number of preferred embodiments of the invention has
been shown and described herein, modifications thereof may be made
by one skilled in the art without departing from the spirit and the
teachings of the invention. The embodiments described herein are
exemplary only, and are not intended to be limiting. Many
variations, combinations, and modifications of the invention
disclosed herein are possible and are within the scope of the
invention. Accordingly, the scope of protection is not limited by
the description set out above, but is defined by the claims which
follow, that scope including all equivalents of the subject matter
of the claims.
* * * * *