Note: Descriptions are shown in the official language in which they were submitted.
CA 02340299 2001-03-08
UNDERLAYMENT COMPOSITE AND ASSOCIATED FLOORING
INSTALLATION SYSTE1~I
CROSS-REFERENCE TO RELATED APPLICATION
'this application is a continuation-in-part application of US Serial Number
09/532,231, filed on March 21, 2000.
FIELD OF THE INVENTION
The present invention is directed generally to the field of surface
coverings. In particular, the present invention is directed to underlayment
assemblies suitable for use with a decorative floor covering.
1o BACKGROUND OF THE INVENTION
Surface coverings, particularly decorative finished flooring products, often
require an underlayment to be installed over a structural wood subfloor or
other
substrate. Commonly, the underlayment is attached to the substrate by
application of an adhesive, nails, screws, staples or any combination thereof.
The
15 underlayment serves as a foundation for the application of the surface
coverings,
and provides a clean, smooth surface upon which to lay the surface coverings.
A
smooth surface is desirable the so that the substrate's texture or Braining is
not
transmitted through to the viewable surface of the surface covering.
Underlayments also should resist dents and punctures from concentrated loads
2o and traffic, and should not contain substances that can stain the surface
covering.
In one such type of application, a liquid adhesive is applied to the exposed
surface of the underlayment, and then the surface covering is laid over the
adhesive which adheres the surface covering to the underlayment. Typically,
the
adhesives are applied at the installation location by employing a notched
trowel to
25 spread the adhesive on the underlayment, which is a labor intensive and
often
messy process. Roll-on and spray-on adhesives may be employed as well. Such
adhesives should firmly bond the surface covering to the underlayment to
prevent
the surface covering from buckling or curling through a wide range of wear and
N2151G3 vl -~11.t8 1271 CIP Patcnt:\p
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environmental conditions. Importantly, the adhesive should not contribute to
staining of the finished flooring. Further, in conventional on-location
adhesive
application, the selected adhesive should have certain attributes or
properties
which make it easy to trowel and provide adequate working time over a wide
variety of substrates or underlayments in combination with a wide variety of
surface covering backing materials. It is known, however, that such liquid
adhesives utilized at the surface covering installation site sometimes have
problems with mildew staining, bottom-up staining from the substrate or
underlayment, seam contamination, and vapor bubbles.
1o Another current practice is to provide an adhesive layer on the back of the
surface covering itself. Pre-applied adhesives primarily have been utilized
for
carpet installation. For example, one installation device includes a thin
scrim
webbing with adhesive on both sides and a release film disposed over the
adhesive on one side. Another similar device is a carpet padding which has a
pressure sensitive adhesive on both sides and a release film disposed over the
adhesive on one side. The exposed adhesive is contacted with the sub floor,
and
the release film is removed to expose an adhesive layer which receives and
bonds
to the carpet. These devices, however, are not appropriate for adhering
surface
coverings such as vinyl flooring to the subfloor. In the case of the scrim
device, it
2o is too varied in thickness, which allows its surface texture to show
through the
vinyl surface covering. Additionally, breakage can occur over its individual
strands when thin, smooth, and glossy surface coverings are installed over
them.
The carpet installation device is likewise unacceptable for vinyl flooring
installation, because it provides too much cushioning and not enough
resiliency to
protect surface coverings, such as vinyl sheet, tile, and veneers and high
pressure
laminate flooring, from indent or deflection-type damage from concentrated
loads. For example, U.S. Patent Nos. 4,557,774, 5,160,770, and 5,304,268 all
to
Hoopengardner disclose a carpet pad with pressure sensitive adhesive and a
removable release film.
3o Surface coverings also are known which have a pressure sensitive
adhesive layer disposed on the back side or backing material. A protective
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covering of a releasable film, such as a release paper or a thermoplastic or
polyethylene film, is disposed over the adhesive layer. During installation,
the
releasable film is removed and the surface covering is pressed onto the
substrate
or underlayment. These surface coverings are produced by applying the
5 releasable film to the adhesive layer by attaching the leading ends of the
film and
the surface covering to a core roll. The surface covering is oriented such
that the
adhesive layer faces inwardly towards the core roll and adjacent the
protective
layer. The core roll then is rotated such that the protective layer is applied
to and
overlies the adhesive surface as the surface covering is simultaneously
collected
10 on the core roll. Self adhering tile, in which adhesive and release film
are on the
back of the tile, are prevalent in the residential flooring segment. Also, as
indicated above, some manufacturers have introduced self adhering sheet
flooring
(roll goods such as carpet and vinyl). This concept, however, usually involves
the
application of both adhesive and release film to the back of the sheet
flooring by
is the installer. Factory applied adhesive to sheet goods presents a unique
set of
concerns to manufacturers of conventional flooring products due to
manufacturing, logistical, packaging and storage issues.
U.S. Patent 4,397,906 to Nakagawa et al. discloses a multilayer backing
material consisting of a polyolefin or polybutadiene foam sheet base layer, a
dry
20 coated interlayer of polychloroprene-type adhesive, and a dry coated layer
of a
mixture of a water-based adhesive and an inorganic filler. The interlayer and
dry
coated layer can be disposed on one or both sides of the backing material. The
dry coated adhesive layers allow use of water-based adhesives to adhere the
backing material on one side to wall paper or a non woven fabric and the other
25 side to a floor, wall, or ceiling.
Despite the existing methods of adhering a surface covering to an
underlayment, the need for a underlayment assembly that provides a smooth,
indent resistant surface for the installation of surface coverings remains.
Further,
there remains a need for a underlayment assembly which has a pre-applied
30 adhesive layer suitable for bonding a variety of surface coverings, such as
finished flooring products, and a release film or paper disposed on the
surface.
tt215163 v l - A 148 1271 CIP Patent Ap
CA 02340299 2001-03-08
Still further, there remains a need for a method of installing a underlayment
assembly over a sub floor system typically found in residential building
construction, that employs staples or other like mechanical fasteners.
Finally,
there remains a need for a method of installing a surface covering onto a
5 underlayment assembly. It is to the provision of a underlayment assembly and
associated flooring installation system that meets these needs that the
present
mvenhon is primarily directed.
SUIVIlVIARY OF THE INVENTION
Briefly described, a underlayment assembly of the present invention
10 comprises a substantially rigid underlayment having an upper and a lower
surface,
a pressure sensitive adhesive layer disposed on the upper surface, and a
release
layer disposed on the adhesive layer. Another pressure sensitive adhesive
layer
and another release layer are optionally provided on the lower surface of the
underlayment assembly. One or more performance enhancing layers, such as
15 foam and solid layers, are disposed bet<veen the underlayment and the
adhesive
layer to modify and/or enhance various properties of the underlayment
assembly.
Mechanical fasteners, such as staples, penetrate the underlayment assembly and
engage a structural support member, such as a subfloor, to attach the
underlayment assembly thereto.
20 In addition to the above embodiments, the present invention also can
include another type of mechanical fastener attached to the upper surface of
the
underlayment. This mechanical fastener can be incorporated into the
underlayment assembly described above along with the various performance-
enhancing layers. This mechanical or primary fastener can include either the
25 hook portion or the loop portion of commonly known hook and loop fastener
systems. A release layer comprising a release fastener is positioned over the
primary fastener in order to protect the primary fastener during shipment and
installation. The release fastener can comprise the complementary or mating
portion of the hook and loop system, as appropriate, in order to mate with the
it2151 G3 v I - A 143 1271 CIP Patent Ap
CA 02340299 2001-03-08
primary fastener. Additionally the release fastener can comprise a film or
sheet
having an adhesive on its lower surface, or a tape, such as masking tape.
Another aspect of the present invention relates to a method of installing a
surface covering over a structural support member. The method includes
5 providing at least one underlayment assembly made in accordance with the
present invention, positioning the at least one underlayment assembly on the
structural support member, fastening the at least one underlayment assembly to
the structural support member, removing the release layer from the at least
one
underlayment assembly, and placing the surface covering onto the adhesive
layer
to of the at least one underlayment assembly. The surface covering may be
pressed
against the underlayment during installation. The underlayment assembly is
fastened to the structural support member by the mechanical fasteners. Each
mechanical fastener preferably has a crown and the crown is recessed within
the
underlayment assembly such that the crown is substantially below the surface
15 covering/adhesive interface to provide a substantially protrusion free
surface
covenng.
In the case of the embodiment using a primary mechanical fastener of the
hook and loop type, the underlayment assembly which includes the primary
fastener is fastened to the structural support member by passing the crown of
the
20 staple where other appropriate fastener through the primary fastener so
that the
crown is below the primary fastener.
Thus, a unique underlayment assembly and associated flooring installation
system is provided that successfully addresses the shortcomings of existing
underlayments and surface covering installation systems and provides distinct
25 advantages over such underlayments and systems. Additional objects,
features,
and advantages of the invention will become more apparent upon review of the
detailed description set forth below when taken in conjunction with the
accompanying drawing Figs., which are briefly described as follows.
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CA 02340299 2001-03-08
BRIEF DESCRIPTION OF THE DRA'VINGS
Fig. 1 is a partial view shown in top perspective of an embodiment of a
underlayment assembly made in accordance with the present invention installed
on a subfloor.
Fig. 2 is a partial view shown in top perspective of a second embodiment
of a assembly made in accordance with the present invention.
Fig. 3 is a partial view shown in top perspective of a third embodiment of
an underlayment made in accordance with the present invention.
Fig. 4 is a partial view shown in top perspective of the underlayment of
Fig. 3 secured to the subfloor.
Fig. ~ is a partial view shown in perspective of another embodiment of the
present invention.
Fig. 6 is a partial view of the embodiment of Fig. 5 showing the
underlayment secured to the subfloor.
DETAILED DESCRIPTION OF THE INVENTION
For a more complete understanding of the present invention, reference
should be made to the following detailed description taken in connection with
the
accompanying drawings, wherein like reference numerals designate
corresponding parts throughout the several Figs. Referring to Fig. 1, Fig. 1
illustrates an embodiment of a underlayment assembly 10 made in accordance
with the present invention for the installation and bonding of surface
coverings
(not shown), such as floor, wall, and ceiling coverings thereto, which
eliminates
the need for on-site adhesive application. In this embodiment, the
underlayment
assembly 10 comprises an underlayment 12 which has an upper surface 14 and a
lower surface 16, a pressure sensitive adhesive layer 18 pre-applied to the
upper
surface 14, and a release layer 20 disposed on the adhesive layer 18.
Referring to Fig. 2, another embodiment of a underlayment assembly 10
of the present invention is illustrated. The lower surface 16 of the
underlayment
12 is coated with a second adhesive layer 18~ to enhance attachment of the
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CA 02340299 2001-03-08
underlayment 12 to the structural support member 2. A second release layer 20~
is
provided to cover adhesive layer 18~ until assembly 10 is ready for
installation.
This adhesive layer 18~, in addition to the mechanical fasteners 28, is
utilized to
secure the underlayment 12 to the structural support member 2. In particular,
if
the structural support member 2 is a subfloor, this adhesive layer 18~ assists
in
maintaining a "silent" floor. Often, the mechanical fasteners 28 can loosen
from
the subfloor over time, and create noise when the flooring is walked upon. The
additional adhesive layer 18~ fizrther secures the underlayment 12 to the
subfloor.
This adhesive layer 18~ and associated release layer 20~ may be the same or
to different from the adhesive and release layers 18 and 20 disposed on the
upper
surface 14 of the underlayment 12 or the performance layer 22.
Referring now to Figs. 3 and 4, the underlayment assembly 10 comprises
one or more performance enhancing layers 22 disposed on the upper surface 14
of
the underlayment 12. The performance enhancing layers 22 can provide, for
example, improved impact resistance, barrier properties to limit migration of
staining agents and moisture from the structural support member 2, and
cushioning properties for comfort including short term exposure, such as
walking,
and long term exposure, such as standing. Further, sound absorbing and
transfer
properties can be modified by the performance enhancing layers 22.
2o Additionally, the performance enhancing layers 22 can fill in irregularly-
shaped
areas in upper surface 14, which create additional surface area to be coated
by the
adhesive, to provide a substantially uniform, smooth surface upon which to
apply
the adhesive layer 18. As a result, the amount of adhesive needed to coat the
underlayment assembly 10 can be reduced. Such performance enhancing layers
22 may include one or more foam layers 24 and/or solid layers 26. The foam
layer 24 imparts energy absorption with little or no permanent indent.
Additionally, the foam layer 24 comprises a mechanical cushioning layer.
Preferably, each foam layer 24 is between about 10 mils to about 100 mils
thick.
The solid layer 26 includes one or more filled or unfilled polymeric film
layers
3o which can either be coated directly on the underlayment or preformed and
laminated to the underlayment. Preferably, each solid layer 26 has a thickness
#2t~163 vl -A143 1271 CIP PatentAp
f
CA 02340299 2001-03-08
between about 1 mil to about 100 mils. As shown in Fig. 3, a solid layer 26,
such
as an unfilled polyvinyl chloride film layer, is disposed on the upper surface
l~ of
the underlayment 12, and a foam layer 24 is disposed on the solid layer 26.
The
adhesive layer 18 is coated onto the foam layer 24, and the release layer 20
is
releasably disposed on the adhesive layer 18. As shown in Fig. 4, a first
solid
layer 26 comprising a filled hot melt calendered ("HMC") polyvinyl chloride
layer is disposed on the upper surface 14 of the underlayment 12. A second
solid
layer 27 comprising an unfilled polyvinyl chloride film layer is disposed on
the
HMC layer, thereby forming two solid layers disposed on the underlayment 12.
The adhesive layer 18 is coated onto the unfilled polyvinyl chloride film
layer 27,
and the release layer 20 is releasably disposed on the adhesive layer 18. The
thickness of the foam and solid layers 24 and 26 are variable depending upon
the
desired performance enhancement to the underlayment assembly 10.
The release layer 20 facilitates storage of the underlayment assembly 10 in
stacks without blocking, protecting the adhesive from dirt and debris during
installation, and permits the finished surface covering to be cut, handled,
and
otherwise maneuvered on top of the underlayment assembly 10 prior to adhering
the surface covering to the underlayment assembly 10. Preferably, the release
layer 20 comprises a release paper or a release film. Release papers include
papers coated with a polymer coating, such as carbon based polymers including
polyolefin copolymers, polyesters, polyamides, polyimides, and polyurethanes,
or
a silicone coating comprising silicone monomers and/or polymers. Release films
include films formed from polyolefin copolymers, polyesters, polyamides,
polyimides, and polyurethanes. Notably, any release layer 20 comprising a
composition capable of being bent and removed from the adhesive layer is
suitable for use with the present invention.
After the surface covering is fitted over the underlayment having the
release paper for installation, the surface covering is either lifted, in the
case of
tile, planks, or otherwise small and relatively rigid modules, or folded back
on
3o itself in the case of sheet vinyl or carpeting, so that the release layer
20 can be
peeled away to expose the adhesive. Once the release layer 20 is removed, the
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CA 02340299 2001-03-08
surface covering is returned to the underlayment assembly 10 and placed in
contact with the adhesive to form an adhesive and/or mechanical bonding of the
surface covering to the underlayment 12.
The underlayment 12 comprises any conventional material utilized as an
5 underlayment in the construction industry. Preferably, the underlayment 12
is
formed from a substantially rigid natural or synthetic material. For example,
an
underlayment 12 of one foot in length which is only supported at one end that
does not bend more than 45 degrees from its weight is considered a
substantially
rigid material. Further, a material which is non-rollable is considered
l0 substantially rigid. Such underlavments 12 include without limitation
plywood,
particleboard, oriented strand board, fiberboard, hardboard, fiber reinforced
gypsum board, fiber cement board, cemetitious backerboard, boards comprising
recycled materials such as paper, plastic board, fiber/plastic composite
board, and
any board made from a material having the desired density and smoothness to
15 make it acceptable as an underlayment for surface coverings. Typically,
such
underlayments 12 are nominally one-quarter inch in thickness, but the
thickness
can be varied as desired.
The present invention also provides a method and unique installation
system for securing the pregluded underlayment assembly 10 to a structural
2o support member 2 by stapling or tacking through the release layer 20 and
the
adhesive layer 18. As illustrated in Figs. 1 and 4, the underlayment assembly
10
can be fastened to a structural support member 2, such as, but not limited to,
subflooring, sheathing panels, joists, rafters, studs, or furring lath with
mechanical
fasteners 28. Mechanical fasteners 28 include staples, tacks, nails, screws,
and
z5 the like in any combination thereof. Preferably, the pregluded underlayment
assembly 10 is fastened to the structural support member 2 with staples.
Importantly, in the case where the adhesive is a substantially continuous
coating, the mechanical fastener 28 is driven to a sufficient depth such that
the
uppermost portion or crown 30 of the fastener 28 is recessed below the
30 underlaymentJadhesive interface to aide in preventing a protrusion in the
visible
surface of the surface covering. Preferably, the crown 30 is recessed below
the
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CA 02340299 2001-03-08
adhesive/underlayment interface. Likewise, if the underlayment 12 has one or
more performance enhancing layers 22 disposed thereon, the crown 30 is
recessed
below the distal performance enhancing layer/adhesive interface. If the
pressure
sensitive adhesive is disposed on the underlayment 12 or a performance
5 enhancing layer 22 in the form of elongated beads, and the surface covering
comprises a substantially rigid material, such as wood, however, it is only
necessary for the crown 30 of the mechanical fastener 28 to be below the apex
of
the bead.
Preferably, the removable release layer 20, the adhesive layer 18, any
l0 performance enhancing layer 22, and the underlayment 12 are selected so
that
mechanical fasteners 28 can penetrate through the release layer 20, the
adhesive
layer 18, performance enhancing layer or layers 22 if present, and the
underlayment 12 to anchor or fasten the underlayment 12 to the structural
support
member 2, such as a subfloor, and have the crown 30 of the mechanical fastener
15 28 embedded in the underlayment 12. The release layer 20 readily releases
from
the adhesive layer 18 even after the mechanical fasteners 28 have penetrated
the
release layer 20.
Pressure sensitive adhesives include any adhesive system that creates a
bond with the flooring material by contact and pressure. There are numerous
2o pressure sensitive adhesives available in the market place suitable for use
with the
present invention. Pressure sensitive adhesives can include those that are
tacky
and remain tacky, those that are tacky initially and harden after contact with
the
flooring material, and those that are non-tacky. Such adhesives include
organic
solvent-based, water-based, and hot melt adhesives. For example, organic
25 solvent- and water-based adhesives include without limitation styrene
butadiene
rubber, styrene isoprene rubber, polyisobutylene rubber, styrene-isoprene-
styrene
("SIS") and styrene-butadiene-styrene ("SBS") block copolymer rubbers, natural
rubber, acrylic homopolymers and copolymers, vinyl acetate copolymers,
polyesters, polyurethanes, and asphalt. Hot melt pressure sensitive adhesives
3o include without limitation amorphous polypropylene, polyisobutylene,
ethylene
vinyl acetate, polyesters, ethylene acrylic acid copolymers, SIS and SBS block
#215163 v l - A I.1~ 1271 C1P Patcnt AP 10
CA 02340299 2001-03-08
copolymer rubbers, and polyurethanes. Additionally, hot melt adhesives also
include contact responsive materials such as those described in U.S. Patent
No.
5,888,335 to Kobe et al. These organic solvent-based, water-based, and hot
melt
adhesive polymers can be blended with a lower molecular weight tactifying
resins, such as aliphatic and aromatic hydrocarbons or rosin esters.
Additionally,
such adhesives include plasticizing oils or plasticizers. Further, the
adhesive can
be a blend of rivo or more of these polymers to achieve desired performance
characteristics. Suitable adhesives for use with the present invention include
water-based adhesives S-580 for Flash Coving, S-89 for Tile, H-630 for Carpet
t0 Tile, and H-620 for Vinyl-backed Carpet Tile; organic solvent-based
adhesive S-
89 for Tile; and hot melt adhesive PLACE 'N PRESS for factory application to
tile, all manufactured by Armstrong World Industries, Ine., Lancaster, PA.
Additionally, the adhesive can be a nvo part system adhesive. In this
embodiment, one part of the adhesive is coated onto the underla~~nent 12 and
the
second part is coated onto the back of the surface covering. When the second
part
on the surface covering is contacted with the first part on the underlayment
12, an
adhesive chemical reaction occurs to chemically bond the surface covering to
the
underlayment 12. The adhesive layer 18 can be a substantially uniform layer or
non-continuous. For example, the adhesive can be coated onto the underlayment
12 in the form of beads.
The foam layer 24 includes foamable compositions comprising resinous
compositions containing a chemical blowing agent that is applied to the upper
surface 14 of the underlayment 12 or performance enhancing layer 22 thereon
and
subsequently expanded or blown. Alternatively, froth foams can be utilized
that
are applied to the upper surface 14 of underlayment 12 or performance
enhancing
layer 22 thereon and subsequently cured. Preferably, the foam layer 24 has a
substantially uniform thickness. The foam layer 24 can be coated onto the
underlayment 12 by any suitable conventional coating apparatus (not shown)
such
as a screen coater, a reverse roll coater, a doctor blade, an air knife, or
other
coating apparatus for fluid compositions. If an additional resinous layer is
to be
coated onto the foam layer 24, the coated underlayment 12 is then passed
through
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CA 02340299 2001-03-08
a heating unit (not shown) which supplies sufficient heat to at least
partially gel
the thermoplastic resinous coating without decomposing the blowing agent. Any
conventional heating unit such as a bank of radiant heaters, an oven, and the
like
may be utilized. Otherwise, the temperature of the heating unit can be set
sufficiently high to expand and cure the foam layer 24.
Also, extrusion coating and other melt coating techniques for melt
processable compositions may be utilized to coat the underlayment 12 or
performance enhancing layer 22 thereon with the foam layer 24. Alternatively,
the foam layer 24 can be preformed and laminated to the upper surface 14 of
the
10 underlayment 12 or performance enhancing layer 22 thereon. Depending upon
the material selected, an optional adhesive layer may be required between the
foam layer 24 and the underlayment 12 or the performance enhancing layer 22
thereon.
The foam layer 24 of the present invention can be any conventional foam
layer used in surface coverings, such as a foam layer used in flooring. In
particular, the foam layer 24 can be any suitable material known in the art
for
producing foam layers such as chemical blown polyvinyl chloride
plastisols/organosols, acrylics, polyurethane foams; froth foams such as
polyvinyl
chloride plastisol, acrylics, etc.; and melt processed foams such as polyvinyl
20 chloride, polyethylene, ethylene vinyl acetate, metallocene polyolefins,
elastomeric polyolefin copolymers, etc. Additionally, foams which are cross-
linked may also be employed. Further, fibers or fibrous reinforcing mats may
be
included as part of the foam layer 24. Preferably, the foam layer 24 is a
resilient,
cellular foam layer. Additionally, a non-foam (mechanical cushioning) cushion
25 layer such as SKYDEX'~' made by SKYDEX Cushioning Technologies can also
be utilized in this invention. There are no limitations on the nature of the
foam
layer composition utilized with the present invention except as limited by the
manufacturing process employed and desired performance characteristics of the
underlayment assembly 10.
3o As indicated above, the expandable resinous composition comprising the
foam layer 24 includes an effective amount of a foaming or blowing agent. The
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CA 02340299 2001-03-08
larger the amount of blowing agent within practical limits used, the greater
is the
expansion of the foam. Foaming or blowing agents are well known in the art,
and
the particular blowing agent selected usually depends on such matters as cost,
resin, and desired foam density. Complex organic compounds which, when
5 heated, decompose to yield an inert gas and have residues which are
compatible
with the resin are preferred as foaming or blowing agents. Such materials
should
have the property of decomposition over a narrow temperature range which is
particularly desirable to obtain a good foam structure. Examples of typical
foaming or blowing agents include without limitation substituted nitroso
10 compounds substituted hydrazides, substituted azo compounds, acid azides,
and
guanyl compounds, to name only a few. Foaming or blowing agents for use in the
present invention must be decomposed an effective amount at a temperature
below the decomposition temperature of the resinous compositions and
underlayment 12. The preferred foaming or blowing agents are those that
15 decompose above the elastomeric point of the resin composition of the foam
layer
24 since this enables at least partial gelling of the foam layer 24 so that
additional
layers can be coated thereon if desired. Additionally, accelerators or
catalysts can
be added to the resinous composition of the foam layer 24 to accelerate the
decomposition of the blowing agents, reduce the decomposition temperature, act
20 as stabilizers for the resinous composition, and/or narrow the
decomposition
temperature range. Such accelerators and catalysts are known in the art.
Further
discussion of foaming or blowing agents is provided in U.S. Patent No.
3,293,108,
incorporated herein by reference. Further, the resinous composition can
include
solvents, viscosity modifiers, color and UV stabilizers, and the like.
25 The solid layer 26 comprises a coat or film of a filled or unfilled
resinous
or polymeric composition. The solid layer 26 is applied over either the upper
surface 14 of the underlayment 12, the foam layer 24, or any other solid layer
26
by suitable conventional coating apparatus (not shown) such as a screen
coater, a
reverse roll coater, a doctor blade, an air knife, or other coating apparatus
for fluid
30 compositions. Examples of film layers that can be coated directly on the
underlayment l2 or performance enhancing layer 22, if present, include
polyvinyl
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CA 02340299 2001-03-08
chloride plastisol films, and solvent- or water-based films based upon
polyvinyl
chloride, polyesters, polyamides, polyurethanes, etc. These coated films can
either be thermoplastic or thermoset in nature, and the selection may be
tailored to
cooperate with the manufacturing process employed to coat the underlayment.
5 Additionally, these film layers can be preformed from the compositions
described
above, or they can be formed on the underlayment or performance layer by
calendering or extrusion processes. These film layers can also include
polyethylene terephthalate, polyvinyl chloride, polyolefin homo- and
copolymers,
polyurethanes, polyamides, polyesters, polyvinylidene chloride, etc. Depending
l0 upon the film layer selected, an optional adhesive layer may be required
between
the underlayment and the film layer. Preferably, the film layer has a
substantially
uniform thickness across the underlayment 12 or the performance layer 22, if
present. The film layer can be transparent, translucent, or pigmented opaque.
It
can also contain fibers or reinforcing fibers or fibrous mats. The film layer
15 employed should adhere to the underlayment and/or performance layer, if
present,
and should be compatible with the adhesive/release paper, as well as the
product
installed in contact with this adhesive.
After applying the solid layer 26, if the solid layer 26 comprises a heat
curable composition, the coated underlayment 12 is passed through a heating
unit
20 (not shown) which supplies sufficient heat to at least partially gel the
solid layer
26 if an additional fluid resinous composition is to be applied. For example,
if the
expandable foam layer 24 is present and additional performance enhancing
layers
22 are desired, the temperature of the heating unit should be sufficient to at
least
partially gel the wear layer without decomposing the blowing agent. Again, any
25 conventional heating unit such as a bank of infra-red heating lamps, an
oven, and
the like may be utilized. Otherwise, the temperature of the heating unit can
be set
sufficiently high to cure the wear layer.
The term "gel" includes both the partial solvation to the elastomeric point
of the resinous composition and complete solvation of the resin or resins with
the
30 plasticizer to fuse the resinous layers. For example, the temperature is
raised to
between about 275° F. and 325° F., preferably about 300°
F., to gel the polyvinyl
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chloride resinous compositions. If the non-gelled foam layer 24 or the gelled
foam layer 24 and non-gelled wear layer are to be cured, the coated
underlayment
12 is then passed through a fusion oven (not shown) to expand and cure the
foam
layer and/or cure the wear layer. The fusion oven can be any heating apparatus
5 such as a hot air impingement oven or in&a-red heat lamps. The fusion oven
raises the temperature of the resinous compositions on the underlayment 12
sufficiently high to cause the selective decomposition of the blowing agent
contained in the foam layer 24 and to completely solvate and fuse all resinous
layers on the underlayment 12. Upon exiting the fusion oven, the coated
10 underlayment 12 is preferably allowed to cool prior to applying the
adhesive layer
18.
If desired, a solid layer 26 comprising the HMC layer manufactured by a
HMC process can be coated onto any of the underlayment 12, the foam layer 24,
or other solid layer 26. HMC refers to the process of formulating a
homogeneous
15 mixture containing a hot melt processable resin and preferably plasticizer,
stabilizer, filler, and other ingredients, heating the mixture, and delivering
the
heated mixture to a calender where the mixture is applied in a precisely
controlled
thickness to the underlayment 12 or the foam or solid layers 24 and 26 thereof
to
form a laminated underlayment 12. Such melt processable resins include, but
are
2o not limited to, polyvinyl chloride (including general purpose polyvinyl
chloride as
defined in ASTM Standard D1755-92), polyethylene, polypropylene, polystyrene,
and copolymers thereof. Fillers include, without limitation, mineral fillers,
such
as clay, talc, dolomite, and limestone. The HMC composition may be tailored to
achieve the desired performance enhancing characteristic for the underlayment
25 assembly 10.
The constituents of the HMC layer are mixed in a mixer (not shown), and
fed into a calender (not shown) at a desired mix temperature. The calender nip
opening (not shown) of the calender is adjusted to the desired thickness of
HMC
layer, and the HMC layer is melt-coated directly onto the underlayment 12 or
any
30 layer thereon by bringing the underlayment 12 or layer thereon into contact
with a
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calender transfer roll (not shown) in a continuous process to form a laminated
HMC underlayment 12.
Optionally, besides the layers discussed above, one or more additional
layers can be present, such as the layers described in U.S. Pat. No. 5,4S8,9S3
to
5 GYang et al., incorporated herein in its entirety by reference. Such
additional
layers include strengthening layers, additional foamable layers, and a wear
layer
base coat. The composition of these layers and their locations are described
in
U.S. Pat. No. 5,458,953 and can be used in underlayment assembly 10 of the
present invention. Such layers are disposed between the underlayment 12 and
the
1o adhesive layer 18.
EXAMPLES
Example 1
Various types of conventional underlayments were coated with an acrylic
copolymer emulsion pressure sensitive adhesive. The underlayment sample size
15 varied from 12"xl2" to 24"x24", and ranged in thickness from .20" (5.2 mm)
to
.375" (9.5 mm). Underlayments included plywood, such as fir, poplar, arctic
birch, and lauan, various species of oriented strand board, particleboard,
hardboard or fiberboard, and fiber-reinforced gypsum and cementitious boards.
The adhesive used was Armstrong S-580 FLASH COVE ADHESIVE, an acrylic
2o polymer emulsion supplied by Franklin International, described as COVINAX
379-02. COVINAX 379-02 is a surfactant-stabilized, acrylic copolymer for use
as a permanent pressure sensitive adhesive containing 62%-64% solids and 8.6
lb.
per gallon.
The adhesive was applied with a 3/16" nap paint roller and allowed to air
25 dry. Tests conducted with one and two coats of adhesive, depending on the
texture and porosity of the underlayment substrate, yielded dried weights of
the
adhesive film ranging from 3.3 grams/ftZ to 11 grams/ ft'. Upon drying, a
white,
silicone treated release paper obtained from Peterson Scanproof, Saffle,
Sweden,
typical of that used on the back of place-and-press self adhering tile, was
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positioned on top of the adhesive film. The silicone treated side was
positioned
adjacent the adhesive layer, and rolled into place with a hand roller. Typical
values of the release paper were: Caliper, 2.2 mils; Tensile, 30 lb./in ivlD,
13
lb./in Al'~m.
Example 2
Underlayments coated with adhesive as described in Example l, had the
adhesive layer covered with alternative release papers and release films.
These
included polyethylene and/or polypropylene sheeting in various thicknesses
ranging from 1 mil to 10 mils. Other felts and papers with various release
coatings employed in the manufacture of vinyl flooring were also employed as a
release layer on top of the adhesive layer. Silicon release coated paper
obtained
from SD Warren Company, flooring release paper carrier corresponding to U.S.
Patent No. 4,423,100, polypropylene coated paper obtained from Fortifiber
Corp.,
and release paper used to protect plexiglas sheeting (Cyro Acrylite~) from
Cyro
Industries were employed. Small samples were created using various tapes, such
as paper masking tape and duct tape, to cover the upper adhesive side of the
sample so that the characteristics of the protective covering could be
determined
when fasteners were plunged through the top surface as described in Example 3
below.
2o E!cample 3
The method of installing the underlayment assembly was demonstrated by
stapling the underlayment to a structural wood panel typical for sub
floorings.
Although any conventional stapling tool capable of inserting a staple into a
sub floor and an underlayment may be utilized in the method of the present
invention, pneumatic staplers manufactured by Paslode {a division of Illinois
Tool
Works) and Spotnails, Inc. were used in this example. The stapling tools
employed were pneumatic, electric, or manually activated with a mallet and
were
an "oil-less" design to prevent contamination which could compromise adhesion
or cause staining. The staples were 18 gauge, chisel or divergent chisel point
of
3o 5/8" to 1" length with a crown of 3/16" to 1/4". The air pressure was
regulated to
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conform to the stapling tool manufacturer's recommendations and adjusted as
appropriate for the type of subfloor and the underlayment assembly employed.
Generally, pressure ranged from 75 psi to 100 psi, so that the staple
penetrated
through the release layer and the adhesive layer, with the final placement of
the
5 staple having the top of the crown just recessed in the underlayment
substrate
below the plane of the adhesive/substrate interface, as indicated in Figs. l
and 4.
When penetrated with the staples, underlayments with a release layer of a
white, silicone treated release paper showed that the staple and plunger
device on
the staple gun would cut a small rectangular hole in the release layer
to approximating the size of the staple crown. This small cut out of release
layer
was carried by the staple into the underlayment and did not interfere with
overall
surface smoothness of the underlayment. It was found that most of the other
paper and felt release layers and protective tapes were cut in similar
fashion,
having the displaced cut out portion carried below the adhesive layer and
trapped
15 underneath the crown (top) of the staple in the underlayment.
Some polyolefin or polyethylene release films would sometimes show a
similar cut out mechanism to the paper release layers when penetrated by the
staples. Other polyolefin films, depending on their physical properties would
show more of a cut or slit in the film rather than an actual "cut out". There
was
2o also some elongation deformation of some polyolefin films. This was noted
in the
subsequent examples when the release layer was actually peeled from the
adhesive layer in preparation for bonding the finished flooring. There was
occasional tearing away of the portion of film trapped under the crown of the
staple from the main portion of the release film.
25 Example 4
The ability to peel off and remove the various top layer release papers and
films was tested by lifting up one corner of the release layer and then
removing it
in a peeling fashion from the pre-applied adhesive layer. Most of the coated
paper and polyolefin film release layers released with a minimal amount of
effort
3o and left behind a clean, tacky adhesive surface on the upper surface of the
underlayment, ready to accept the floor covering. The silicon release paper
from
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SD Warren and the release paper corresponding to U.S. Patent No. 4,23,100 did
not release cleanly and left too much residue on the adhesive. This is
primarily
due to the relative thickness of the paper. In this initial testing the
silicone treated
papers at 2.2 mils thickness, and the polyethylene sheeting in the 5 mils
thickness
range showed satisfactory results. Polyethylene film of approximately 1.0 mil
to
1.5 mils thickness would sometimes elongate and tear leaving a small torn
piece
behind on the adhesive where a staple penetration was located.
Suitable release layers allowed the staple to penetrate through and into the
underlayment, had sufficient durability to support limited traffic during the
l0 cutting and fitting process of the decorative floor covering, were easily
removed
from the adhesive leaving a clean, smooth adhesive surface and did not pre-
release during cutting and handling of the underlayment.
E~cample 5
Samples of various floor coverings were bonded to the exposed adhesive
15 layer after the protective release layer was removed. The flooring types
included
dry-back residential tile, SUCCESSOR INTERFLEX sheet flooring, INITIATOR
and STARSTEP sheet flooring in both conventional felt and ToughGuard'~
structures, and glass-encapsulated, vinyl-backed sheet structures, all in the
vinyl
flooring category and all made by Armstrong World Industries, Inc., Lancaster,
2o PA. Urethane and vinyl-backed carpet and carpet with ACTION BAC'~ and hot
melt backings were also adhered to the underlayments.
After being laid on top of the adhesive layer, the flooring samples were
rolled with a hand roller as is typical of bond testy in the laboratory. The
resultant
bonds were checked by starting in the corner of the flooring sample and
25 attempting to peel the sample from the underlayment. The initial bonds were
found to be stronger than that of conventional troweled-on, water-based
adhesives. Some of the felt-backed vinyl floors showed a delamination of the
felt
backing when peeled. Some of the urethane foam backings on carpet samples
also showed delamination of the foam. Other vinyl-backed carpet and vinyl
sheet
3o goods peeled rather cleanly from the adhesive film with sufficient effort.
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Therefore, a wide variety of flooring products can be bonded with the
underlayment assembly and this method of installation. Also, the adhesive
types,
formulations, and thickness of the adhesive layer may be tailored and adjusted
so
as to achieve optimum performance with particular types of floor coverings and
5 may be designed to give the desirable traits of releasability and reuse with
subsequent floor coverings.
Example 6
Six larger prototypes were prepared by applying an adhesive layer and a
release layer to 2 ft. x 2 ft. underlayments so that a total of 24 sq. ft.
could be
to installed on a 4 ft. x 8 ft. piece of structural subflooring positioned on
a
supporting surface. An installation simulation was then performed. The
underlayment was fastened to the subflooring using staples as described in
Example 3. While working on top of the underlayment, nvo pieces of rotogravure
printed vinyl flooring were cut and fit to the size of the panel with the
pattern
~ 5 matched where the two pieces of vinyl flooring overlapped. A seam then was
cut
in the vinyl using a conventional double-cut seam method. One-half of the
vinyl
flooring was lapped back at,a time to allow for removal of the release layer
on the
underlayment. The release layer was removed and the vinyl laid back down in
position on top of the adhesive. The seam area was rolled with a hand roller,
and
2o the remaining vinyl in contact with the adhesive was lightly rubbed with
hand
pressure and a clean dry cloth. The remaining half of the flooring was lapped
back so that the release layer could be removed and then carefully laid back
in
position. This portion of the seam area was likewise rolled with a hand
roller.
The entire installation was then rolled with a 100 lb. roller. The resultant
25 installation was firmly bonded and could be trafficked immediately without
tracks
being made in the freshly installed flooring.
Example 7
Two 2 ft. x 2 ft. x 1/4" thick pieces of underlayment comprising oriented
strand board were coated with plastisol, and the plastisol was gelled and
cured at
3o approximately 350° F. One board had a plastisol clear coat
formulation of
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approximately 3.5 mils thick applied to it, while the other board had a
foamable
plastisol formulation of approximately 8 mils thick applied to it. Both
plastisols
were generically typical of formulations used in the manufacture of vinyl
flooring.
The resultant upper surface of the underlayment showed improved smoothness
and uniformity over the underlayments described in Examples 1-6.
Therefore, a plastisol layer can be coated onto the upper surface of the
underlayment to improve or enhance desirable characteristics, such as
smoothness, underfoot comfort, acoustical properties, performance properties
of
the decorative floor covering, and to reduce the amount of adhesive required
or
improve the adhesive performance of the adhesive layer.
Example $
Armstrong S-580 adhesive (Armstrong World Industries, Inc., Lancaster,
PA) was applied to the plastisol coated surface of the two underlayment
samples
described in Example 7. After the adhesive had air-dried, a polyolefin film
15 release layer was placed on top of the adhesive layer. Additional
intermediate
layers, therefore, can be incorporated between the underlayment and the
adhesive
layer in the underlayment assembly of the present invention.
Example 9
The underlayment assembly samples with plastisol interlayers described in
Example 8 were installed with staples on top of a structural subfloor panel.
The
release layer was removed and samples of both vinyl-backed and felt-backed
vinyl floors were installed on them.
Additional embodiments of the present invention incorporate a mechanical
fastener into an underlayment assembly, as shown in Figs. 5 and 6. The
preferred
type of mechanical fastener comprises a cooperative hook and loop assembly, a
first part of which is incorporated in the underlayment assembly and a
cooperating
or second part of which is incorporated into the surface covering supported by
the
underlayment assembly in use.
Fig. 5 shows underlayment assembly 110, comprising an underlayment
base 112, having an upper surface I 14, a lower surface 1 16, and a protective
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covering or release fastener 120. An adhesive layer 118 covers, either
partially or
entirely, upper surface 114. The adhesive can be a contact or pressure
sensitive
adhesive, although the present invention works well with various adhesives
which
bond a mechanical fastener to upper surface 114 sufficiently to prevent either
lateral movement of the mechanical fastener or the separation of the fastener
from
the underlayment base 112 by normal movement. The adhesive must be
compatible with both the composition of mechanical fastener and the
underlayment base 112. Specific types of adhesives found satisfactory for use
as
adhesive layer 118 are listed above with respect to the previous embodiments,
and
l0 in Examples 10, 1 l and 12 of the present embodiment.
A primary fastener 130 is attached to the upper surface 114 of
underlayment base 112 by adhesive layer 118. Primary fastener 130 is a
mechanical fastener, most suitably either a hook fastener or a loop fastener,
although other types of mechanical fasteners suitable to accomplish the
securing
of a surface covering to an underlayment are within the scope of the present
invention. The primary fastener can be of the hook and loop type commonly
known as VELCRO~, which is available from VELCRO, USA, Manchester,
New Hampshire. As is commonly known, a hook and loop system of this type
comprises a hvo part, cooperative mechanical system with a hook component
2o adapted to mate with a loop component. In the present invention, the
primary
fastener 130 can comprise either the hook component or the loop component. It
is
preferred, however, that the primary fastener be comprised of the hook
component. Most preferred are hooks that impact a strong adhesion to a loop
component attached to a surface covering (not shown), to prevent appreciable
lateral or appreciable normal movement between the two components. The
primary fastener also can comprise a nodule and loop system, as well as other
mechanical fastening systems.
It also is preferred, although not required, to have a protective covering
positioned over the primary fastener, in order to protect the primary fastener
3o during handling, such as transport, storage and installation of the
underlayment
assembly 110. If incorporated into the present invention, the protective
covering
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can comprise a mechanical fastener, such as a hook fastener or a loop
fastener, or
a nodule and loop fastener, typically in sheet form. If a hook fastener is
used as
the primary fastener, the protective covering, or release fastener 120, should
comprise a loop fastener or loop component of a hook and loop assembly.
5 Conversely, if the primary fastener 130 comprises a loop fastener, the
release
fastener should comprise a cooperating or mating hook fastener. Nodule and
loop
mechanical fasteners also can be selectively used as either the primary or the
release fastener. The type of release layer or release fastener 120, if used,
is not
limited to a hook and loop fastener component, but also can comprise a release
10 layer of the type described in the previous embodiments. Additionally, the
release
fastener 120 can comprise tape, either in sheet or strip form, such as tape
commonly referred to as masking tape. A tape fastener found usable with the
present invention is TESA 53123 Light Duty Tape manufactured by TESA TAPE,
Inc., Charlotte, North Carolina. If a release fastener or layer 120 is used,
the
15 strength of the mechanical bond between the release layer 120 and the
primary
fastener 130 should be sufficiently low to permit easy removal during
installation
without damaging the primary fastener or removing the primary fastener from
the
underlayment base 112. The strength of the bond between the release layer 120
and the primary fastener 130 should be less than that of the bond behveen the
20 primary fastener 130 and the underlayment base 112. The strength of the
bond
between the release layer 120 and the primary fastener 130 is less than the
strength of the bond bettveen the surface covering (not shown) and the primary
fastener 130.
The above components of the present embodiment comprise underlayment
25 assembly I 10, although as discussed above, the present invention does not
require
the release layer or fastener 120. Additional components, such as performance
enhancing layers of the type and of the composition described above with
respect
to the previous embodiments can be used. As in the previous embodiments, the
performance enhancing layer or layers, if used, are positioned below adhesive
30 layer I 18 and above underlayment base 112. Additionally, the primary
fastener
can be manufactured from any of the compounds discussed above which form a
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performance enhancing layer, such as a foam layer, solid layer or combinations
thereof. In this case, the primary fastener, itself, functions as a
performance
enhancing layer. Further, in the manufacturing process of the underlayment
assembly 110, it is possible to optionally eliminate the adhesive layer 118
and
5 adhere the primary fastener 130 directly to underlayment base 112. For
example,
the underlayment base 112 can include adhesive or tacky material and/or resin
which provides tack to the surfaces of the underlayment base. Otherwise, the
primary fastener 130 can be laminated to the underlayment base 112 by
subjecting
the primary fastener 130 to heat and contacting the heated fastener 130 to the
underlayment base 112.
The present invention also includes the method and installation system for
securing the underlayment assembly 110 to a structural support member 102
(Fig.
6). The method and installation system for underlayment assembly 110 of the
present embodiment includes stapling or tacking assembly 110 through the
release
15 fastener or release layer 120 and the primary fastener 130 as shown in Fig.
6. The
types of structural support members contemplated in relation to the present
invention and the types of mechanical fasteners used to attach underlayment
assembly 110 to a structural support member 102 are identical in the present
embodiment as in the previous embodiments discussed above. As in the previous
2o embodiments, preferably the underlayment assembly 110 is fastened to the
structural support member 102 with staples. The mechanical fastener 128 is
installed so as to penetrate into underlayment assembly 110 so that the crown
128a of the fastener is preferably below the upper surface of the primary
fastener.
The shank 128b of the fastener is driven through the underlayment base 112 and
25 into the subfloor material 102. Additionally, the mechanical fastener 128
will be
driven through any release layer or release fastener 120, if present, during
installation of mechanical fastener 128.
After securing underlayment assembly 110 to a supporting structure, such
as subfloor 102, the release fastener or layer 120 is removed from the primary
30 fastener to expose the primary fastener. A surface covering, such as
flooring,
ceiling covering or wall covering, is then positioned over the primary
fastener to
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contact the primary fastener. Pressure may be applied to the surface covering
(not
shown) to effect a suitable bond between the primary fastener and the surface
covering. Such surface covering will have the cooperative or mating component
attached to the undersurface thereof.
s
ADDITIONAL EXAMPLES
Example 10
A primary, hook-type fastener, Hook 29PP, available from Velcro USA,
Inc. was adhered to a plywood underlayment base panel using the pressure
to sensitive or contact adhesive, Acronal V210, available from BASF
Corporation,
Charlotte, North Carolina. A release fastener or release layer comprising a
loop-
type mechanical fastener, Aspen Loop, available from Velcro USA, Inc., was
applied to the primary fastener to complete the underlayment assembly. The
underlayment assembly was installed to a subfloor as described in Example 3.
15 The staples used to attach the underlayment assembly to the subfloor were
driven
into the subfloor so that the staple crown was positioned below the upper
surface
of the primary fastener. A fabric backed surface covering, Mannington
Performer
I Back, pattern number 62089 floor product, was installed onto the primary
fastener as described in Example 6. The resulting installation is firmly
bonded
2o together, and could be trafficked immediately.
Example 11
The type of primary fastener, Hook 29PP, was attached to a plywood
underlayment, as described in Example 7. The release fastener or release
layer,
25 however, comprised masking tape, which was applied to the upper surface of
the
primary fastener. The masking tape was TESA X3123 Light Duty Tape, available
from TESA TAPE, Inc., Charlotte, North Carolina. The underlayment assembly
was installed to a subfloor as described in Example 3. The surface covering of
the
type described in Example 7 was installed onto the primary fastener, using the
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method described in Example 6. The resulting installation was firmly bonded
and
could be trafficked immediately.
Example 12
This example was manufactured and installed identically as the product
and installation described in Example 8, except that the release fastener
comprised
a masking tape, ST-24: PP-T-42C, type 2, available from Spec Tape, Inc.,
Cincinnati, Ohio. This tape used was 8 mils in thickness.
10
Although the invention has been described in detail for the purpose of
illustration, it is understood that such detail is solely for that propose,
and
variations can be made therein by those skilled in the art without departing
from
the spirit and scope of the invention which is defined by the following
claims.
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