Note: Descriptions are shown in the official language in which they were submitted.
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FLOOR MATTING/CARPETING
This application claims the benefit of Great Britain Patent Application No.
GB0620907.6,
filed October 20, 2006, and Great Britain Patent Application No. GB0702025.8,
filed
February 2, 2007, the disclosure of which is incorporated by reference herein
in its
entirety.
FIELD OF THE INVENTION
The present invention relates to floor matting/carpeting, more especially
matting/carpeting
that is suitable for use at the entrances of buildings or other locations.
BACKGROUND
Entrance mats are used to remove dirt and water (hereinafter referred to
generally as
"soil") from the shoes of pedestrians as they enter a building. In some
locations, for
example supermarket and airport buildings, entrance mats are also required to
remove dirt
and water from the wheels of trolleys or similar articles. Accordingly,
reference herein to
the removal of soil from the shoes of pedestrians should be considered to
include the
removal of soil from all traffic (pedestrian and wheeled) that passes over an
entrance mat.
It is recognized that an entrance mat that functions efficiently can greatly
assist in the
maintenance of a building by reducing the amount of cleaning that is required.
In addition,
the owners/occupiers of buildings are increasingly demanding entrance mats
that will
enhance the appearance of their premises.
Various forms of entrance mat are known and, depending on their construction
and the
materials from which they are formed, are placed immediately outside or inside
a building.
Some entrance mats are intended to be disposable (i.e. when they become dirty,
they are
taken up and thrown away and a new mat is put in place), and some are semi-
disposable
(i.e. when they become dirty, they are removed for cleaning, often by washing,
and then
re-used). Other mats are intended to be left in position for longer periods of
time: they are
typically harder-wearing and more-effective in removing soil from shoes, and
have a
greater capacity for trapping and storing the removed soil (so that it is not
subsequently
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carried into the building) without the appearance and effectiveness of the mat
being
adversely affected. A mat of that type can be installed in a recess well in a
floor or laid
directly on the floor as a drop-down mat and may be constructed so that dirt
can fall
through the mat onto the underlying surface: in that way, the surface of the
mat remains
clean and effective on the basis of minimal maintenance, it being necessary to
take up or
roll back the mat only periodically so that the underlying surface can be
cleaned,
following which the mat can be replaced. Any water that is removed and trapped
by the
mat is expected, in time, to evaporate.
Mats generally remove soil from shoes by a scraping and/or wiping action,
depending on
their construction and the materials from which they are formed. Mats that
provide a
scraper action typically have an upper, shoe-contacting, surface that
comprises scraper
edges or projections as described, for example, in US 4 497 858 (Dupont and
Laurent); US
2004/0161988 (Yaw); WO 01/60218 (Milliken & Company); and WO 02/15765
(Construction Specialities (UK) Ltd.). Scraper mats that have proved to be
both durable
and effective in removing dirt from shoes etc. are available, under the trade
names
"NomadTM Terra 8100" and "NomadTM Terra 9100", from 3M Company of St. Paul,
Minnesota, USA. Mats that provide a wiping action typically have an absorbent
textile
upper surface: they are often more aesthetically pleasing than scraper mats,
and are
available in a wide range of colors and designs and with differing
characteristics
depending on the textile fibers and textile constructions from which they are
formed.
Some entrance mats have an operative surface that provides both wiping and
scraping
actions. US 4 820 566 (Heine and Tharpe), for example, describes a tufted
textile mat
comprising fine denier fibers that provide a wiping action, and stiff,
crimped, coarse
denier fibers that provide a scraping action and also form an open structure
in the mat
capable of receiving and obscuring dirt. Examples of mats that comprise fine
and coarse
fibers are those available, under the trade name "NomadTM Aqua", from 3M
Company of
St. Paul, Minnesota, USA. In those mats, the fine and coarse fibers are tufted
into a
primary backing which is then provided with a secondary backing formed, for
example,
from vinyl or a non-woven fleece.
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Other entrance mats are available in which the surface of the mat is divided
into distinct
components having different cleaning functions. Examples of mats of that type
are the
profile mats available, under the trade name "NomadTM Optima", from 3M Company
of
St. Paul, Minnesota, USA. Those mats comprise a plurality of parallel aluminum
profiles
that are linked together, each profile containing an infill of the above-
mentioned
"NomadTM Aqua" matting material. The infill material provides a wiping and a
scraping
action, the latter being supplemented by the scraping action of the profiles.
In addition,
soil removed from the soles of shoes is efficiently retained by the mat,
either by the infill
material or by falling between the profiles into the recess well in which the
mat is
installed.
SUMMARY
There is a demand from consumers for continued improvement in the performance
of
entrance mats. They generally appreciate the ability of some existing entrance
mats to
remove dirt from shoes, to maintain their appearance during use and to be easy
to clean
and wish to see those properties retained. They also continue to expect
entrance mats to be
aesthetically pleasing, and to be available in a wide range of designs and
colors to
complement the building or facility in which they are used. However, consumers
are now
additionally looking for mats that provide improved performance in terms of
removing
water from the shoes of pedestrians, especially under bad weather conditions,
coupled
with an enhanced ability to retain the water and eliminate what is known as
"re-tracking"
(i.e. the possibility that water removed from shoes during one passage over
the mat will be
picked up during a subsequent passage over the mat and carried into the
building or
facility that the mat is intended to protect). Re-tracking not only detracts
from the
appearance of the building or facility but can also result in floors becoming
slippery to the
extent that they present a safety hazard. At present, consumers who encounter
this
problem are usually obliged to spend time and money in arranging for the
delivery of
additional mats to supplement or replace those that have become saturated. In
extreme
conditions, they may even consider the installation of permanent drains
beneath their
entrance mats. The present invention has been made with those issues in mind.
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In some spaces, such as small entrance lobbies in public transport vehicles
(e.g. train
carriages) as well as in buildings, carpeting is required that will perform
the same function
as an entrance mat. Accordingly, reference herein to a mat and/or matting
should be
considered, where applicable, to include carpet and/or carpeting and vice
versa.
Outside the field of entrance matting, it is known to use water-
collecting/drainage layers
under surfaces such as artificial turf or artificial ski slopes to address the
problem of
removing excess water. Examples of such water collecting/drainage layers can
be found in
US-A-2006/0068157 and EP-A-0 452 529.
The present invention provides a mat/carpet comprising an upper layer having a
soil-
removing outer surface for contacting traffic passing over the mat/carpet, and
a lower
layer located below the upper layer, the upper layer comprising textile
fibers; wherein the
upper layer is water-permeable whereby water can drain from the upper layer
into the
lower layer; and the lower layer is arranged to collect, for subsequent
removal, water that
is received from the upper layer.
The mat/carpet may comprise a water-impermeable base layer to contain water
within the
mat/carpet. For example, the lower layer may have a water-impermeable lower
surface for
containing water that collects in the lower layer.
The upper layer of a mat/carpet in accordance with the invention may, for
example,
comprise a textile pile layer that provides the soil-removing outer surface.
The lower layer
may comprise channels through which water can flow in a direction generally
parallel to
the soil-removing outer surface of the mat. Those channels may be provided by,
for
example, extruded polymeric material or by a layer of non-woven material or
coiled web
material. The water-impermeable base layer, when present, may be a rubber or
plastic
sheet, or a rubber or plastic coating on the lower surface of the lower layer.
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BRIEF DESCRIPTION OF THE DRAWINGS
By way of example, mats/carpets in accordance with the invention will now be
described
with reference to the accompanying drawings, in which:
Fig. 1 is a diagrammatic cross-section of an entrance mat in accordance with
the
invention;
Fig. 2 is a diagrammatic plan view of one component of the mat of Fig. 1;
Fig. 3 is a diagrammatic perspective view of another component of the mat of
Fig. 1;
Fig. 4 is a diagrammatic cross-section of a modified form of the component
shown in Fig.
2;
Fig. 5 is a diagrammatic cross-section of another entrance mat in accordance
with the
invention;
Fig. 6 is a diagrammatic perspective view of one component of the mat of Fig.
5; and
Fig. 7 is a diagrammatic cross-section of a modified form of the component
shown in Fig.
6.
DETAILED DESCRIPTION
The entrance mat 1 shown in diagrammatic cross-section in Fig. 1 comprises an
upper
layer 3 and a lower layer 5. As described in greater detail below, the upper
layer 3
comprises a textile floor covering and the lower layer 5 is a water-receiving
layer. The
upper surface of the lower layer 5 is permanently bonded to the lower surface
of the upper
layer 3 as will also be described in greater detail below.
The outer surface 7 of the upper layer 3 of the mat 1 is the surface that
comes into contact
with the shoes of pedestrians who walk over the mat when it is located at the
entrance of a
building or other facility, or the wheels of trolleys or similar objects that
pass over the
mat. The upper layer 3 is intended to remove soil (dirt and water) from that
pedestrian or
wheeled traffic, and to prevent the soil from being carried further into the
building.
The upper layer 3, which is shown separately in Fig. 3, has the form of a
tufted loop-pile
carpet, in which some of the looped tufts (shown diagrammatically, and
indicated by the
reference numeral 9) are formed from fine denier fibers (not shown
individually) and the
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others (also shown diagrammatically, and indicated by the reference numeral
11) are
formed from coarse denier fibers that are textured (i.e. crimped). The looped
tufts 9, 11 are
formed in known manner in a primary backing, to which a secondary backing is
subsequently applied to anchor the tufts in position. In Fig. 1, the primary
and secondary
backings are shown for simplicity as a single backing layer 13. The coarse and
fine fibre
tufts 9, 11 may be randomly interspersed with one another or they may be
arranged in
regular discrete areas to form, for example, a checkerboard pattern or a
pattern of
alternating stripes. The looped tufts 9, 11 have a height typically in the
range of from 9 to
mm, with the fine denier fibers of the tufts 9 having a denier per filament in
the range
10 of about 15 to 50 and the coarse denier fibers of the tufts 11 having a
denier per filament,
before texturization, in the range of about 150 to 500. A preferred material
for the fibers is
polyamide, a preferred material for the primary backing is a
polyester/polyamide non-
woven material, and a preferred material for the secondary backing is
polyvinyl chloride
(PVC), although other suitable materials could be used (including
polypropylene for the
15 fibers and rubber or latex, or a non-woven material for the secondary
backing).
Carpet materials of the type shown in Fig. 3, and variations thereof, are
described in US-
A-4 820 566 and US-A-5 055 333. In the case in which the backing 13 is
impervious, it is
perforated to provide a plurality of apertures 15 that extend through the
whole thickness of
the backing. The purpose of the apertures 15 will be described below.
The lower layer 5 of the entrance mat 1, which is shown separately in Fig. 2,
is an open,
three-dimensional structure comprising a series of straight, parallel,
vertical walls 17
spaced apart by undulating vertical walls 19. The upper edges of the
undulating walls 19
are level with those edges of the straight walls 17 whereas the lower edges of
the
undulating walls are located slightly above those of the straight walls. The
walls 17, 19
may be formed by extrusion and are preferably formed from the same material as
the
lower surface of the upper layer 3 (PVC in this case), although other suitable
materials
could be used. The layer 5 is provided with a water-impermeable bottom
surface,
indicated at 21 in Fig. 1. In this case, the bottom surface 21 is formed from
the same
material as the walls 17, 19. Suitable alternative materials for the walls 17,
19 and the
bottom surface 21 include butyl rubber, neoprene [polychloroprene] rubber,
nitrile
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[acrylonitrile-butadiene] rubber, natural rubber, synthetic polyisoprene
rubber,
polyurethane, polyamide, and polyolefine.
It will be appreciated that the lower edges of the straight walls 17 of the
lower layer 5 are
located on the bottom surface 21 but that the lower edges of the undulating
walls 19 are
located slightly above that surface, whereby the straight walls 17 define a
series of parallel
channels 50 extending over the surface.
Structures of the type shown in Fig. 2, variations thereof, and their
manufacture are
described in US-A-4 631 215.
The entrance mat 1 is assembled by bonding the lower surface of the upper
layer 3 to the
upper surface of the lower layer 5 (i.e. to the tops of the vertical walls 17,
19). The
bonding can be effected in any suitable way, for example using an adhesive.
Preferred
adhesives are hot melt adhesives, applied in discrete locations on the lower
layer 5 to
avoid the formation of an impermeable layer at the interface between the two
layers 3, 5.
In one specific example, the upper layer 3 of the entrance mat 1 is a matting
material
available, under the trade designation "3MTM NomadTM Aqua 8500", from 3M
Company
of St. Paul, Minnesota, USA (the backing of which has been perforated to
provide the
apertures 15) and the lower layer 5 is a matting material available, from 3M
Company,
under the trade designation "3MTM NomadTM Terra 6250". The layers are bonded
together
using a polyurethane hot melt adhesive available, from 3M Company, under the
trade
designation "3MTM Scotch-We1dTM Polyurethane Reactive Adhesive TE100". The
adhesive is applied in discrete locations on the top of the layer 5 using an
applicator gun
available, from 3M Company, under the trade designation "3MTM Jet-We1dTM
Adhesive
Applicator".
The mat 1 is intended to be used as a drop-down mat. The upper layer 3
functions to
remove both dirt and water from the shoes of pedestrians etc. passing over the
mat. More
specifically, the coarse fibers of the tufts 11 of layer 3 remove dirt through
a scraping
action and the fine fibers of the tufts 9 remove water through a wiping
action. The
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removed dirt falls into the tufts, where it is hidden and retained thereby
ensuring that the
upper surface of the entrance mat 1 presents a generally clean appearance and
that the dirt
is not subsequently picked up and tracked into the building. Under normal
weather
conditions, the removed water is trapped by the fine fibers of the tufts 9 and
subsequently
evaporates. Under extremely wet weather conditions, when the upper layer 3
becomes
saturated, the excess water drains through the apertures 15 in the backing 13
and passes
into the lower layer 5 where it is collected on the bottom surface 21. The
channels 50 that
are defined, on the bottom surface 21, by the vertical walls 17 of the lower
layer 5, allow
the water to flow and spread out over the surface 21, rather than accumulate
in one area,
thereby promoting subsequent removal of the water by evaporation when the
ambient
conditions permit. Alternatively, the channels 50 can facilitate positive
removal of the
water if preferred, as described below.
Another form of entrance mat 31 is shown in diagrammatic cross-section in Fig.
5. This
mat also comprises an upper, textile matting, layer 33 bonded to a lower,
water-receiving,
layer 35.
The upper layer 33 of the mat 31 is a tufted, cut-pile carpet in which the
fibers of the tufts
37 are all of one type. The tufts 37 are formed in known manner in a primary
backing, to
which a secondary backing is subsequently applied to anchor the tufts in
position. In Fig.
5, the primary and secondary backings are shown for simplicity as a single
backing layer
39. The tufts 37 typically have a height of about 5 mm, and the weight of the
pile is
typically in the range of from 550 to 600 g/m~. A preferred material for the
fibers of the
tufts 37 is polypropylene, a preferred material for the primary backing is
polyester, and a
preferred material for the secondary backing is polyvinyl chloride (PVC),
although other
suitable materials could be used (including natural materials, or other
polymeric materials
for the fibers and rubber for the secondary backing). The fibers used for the
tufts 37 need
not all be of the same type but could, for example, comprise a mixture of
coarse and fine
fibers. Cut-pile carpet materials of this type are well-known and widely-
available. In the
case in which the carpet backing 39 is impervious, it is perforated to form a
plurality of
apertures 41 that extend through the whole thickness of the material.
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The lower layer 35 of the entrance mat 31, which is shown separately in Fig.
6, is an open,
three-dimensional structure comprising coils of continuous, polymeric
filaments 43 that
loop and overlap one another in a random manner, and are bonded to one another
at their
points of contact. The lower layer 35 may be an extruded component, and is
preferably
formed from the same material as the lower surface of the backing 39 of the
upper layer 33
(PVC in this case), although other suitable materials could be used.
Structures of the type shown in Fig. 6, and their manufacture, are described
in US-A-3 837
988.
The entrance mat 31 of Fig. 5 is assembled by bonding the backing 39 of the
upper layer
33 to the upper surface of the lower layer 35 (i.e. to the tops of some of the
filament
loops). The bonding can be effected in any suitable way, for example using an
adhesive.
Preferred adhesives are hot melt adhesives, applied in discrete locations on
the lower layer
35 to avoid the formation of an impermeable layer at the interface between the
two layers
33, 35.
In one specific example, the upper layer 33 of the entrance mat 31 is a
matting material
available, under the trade designation "Duet" from Rinos of Genemuiden,
Netherlands,
and the lower layer 5 is a matting material available, from 3M Company, under
the trade
designation "3MTM NomadTM Terra 8100". The layers are bonded together using a
polyurethane hot melt adhesive available, from 3M Company, under the trade
designation
"3MTM Scotch-WeldTM Polyurethane Reactive Adhesive TE100". The adhesive is
applied
in discrete locations on the top of the layer 5 using an applicator gun
available, from 3M
Company, under the trade designation "3MTM Jet-We1dTM Adhesive Applicator".
The entrance mat 31 is intended to be placed in a recess well for use. The
upper layer 33
functions to remove both dirt and water from the shoes of pedestrians etc.
passing over the
mat. The removed dirt and water is retained by the tufts 37 and, under normal
weather
conditions, the removed water subsequently evaporates. Under extremely wet
weather
conditions, when the upper layer 33 becomes saturated, the excess water drains
through
the apertures 41 in the backing 39 and passes into the lower layer 35 where it
is collected
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in the bottom of the recess well and contained. The open construction of the
lower layer
35 provides channels that permit the drained water to spread across the recess
well, rather
than accumulate in one area, thereby promoting subsequent removal of the water
by
evaporation when the ambient conditions permit. Alternatively, the channels
provided by
the lower layer 35 can facilitate positive removal of the water if preferred,
as described
below.
It will be appreciated that the upper layers 3, 33 of the mats 1, 31 could be
interchanged to
provide alternative entrance mats in which the upper layer 3 of Fig. 1 would
be combined
with the lower layer 35 of Fig. 5, and the upper layer 33 of Fig. 5 would be
combined with
the lower layer 5 of Fig. 1. It will also be appreciated that the closed
bottom surface 21 of
the lower layer 5 of Fig. 1 could be omitted (as shown in Fig. 4) when the
entrance mat is
for use in a recess well, and that a closed bottom surface 45 could be added
to the lower
layer 35 of Fig. 5 (as shown in Fig. 7) to provide a drop-down mat.
As a further alternative, a tufted pile carpet material of the type comprising
a water-
permeable primary backing and a fleece secondary backing could be used to form
a drop-
down mat by providing a water-impermeable base layer on the lower surface of
the
secondary backing. It will be understood that, in this context, the term
"fleece" means a
non-woven material of a type known to be suitable for use as a carpet
secondary backing
and includes felt materials. In such a construction, the tufted pile and
primary backing
constitute the upper layer of the mat and the fleece secondary backing
constitutes the
lower layer.
One specific example of a mat of that construction comprises a matting
material available,
from 3M Company, under the trade designation "3M NomadTM AquaTM 9500 to the
lower
surface of which is bonded a PVC sheet having a weight of 3 kg/m2 . The layers
are
bonded together using a polyurethane hot melt adhesive available, from 3M
Company,
under the trade designation "3MTM Scotch-We1dTM Polyurethane Reactive Adhesive
TE100". The adhesive is applied in discrete locations on the top of the layer
of the PVC
sheet using an applicator gun available, from 3M Company, under the trade
designation
"3MTM Jet-We1dTM Adhesive Applicator". It is also possible to laminate the
matting
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material to an extruded layer of PVC, while the PVC is still hot and tacky,
thereby
eliminating the need for adhesive.
As an alternative, for a mat of that construction, the tufted pile and primary
backing
forming the upper layer could be provided separately in so-called "greige
good" form and
bonded to a selected fleece layer. The water impermeable base layer may be
applied to the
lower surface of the fleece layer either before or after the fleece layer is
bonded to the
upper layer. The non-woven web that is used for the fleece layer can be
composed of
various materials for example polyester or polyamide, or a mixture of both:
these materials
may be of recycled type. The non-woven should be in a form that is easy to
handle and
process, for example one that is stabilized by needle-punching,
hydroentangling, sewing
or heat welding. Typical web thicknesses are in the range of from 1 to 10 mm,
with a
typical basis weight being in the range of from 100 to 1000 g/m2. One suitable
web is a
spunbond, needle-punched web formed from polyester fibers and having a
thickness of
3.2mm and a basis weight of 300 g/m~, commercially available under the trade
name
VALBOND GEO GAT VRE/5172 from ORV Manufacturing (Peruzzo group) of
Carmignano (PD) Italy.
It will be understood that other constructions are possible for both the upper
and lower
layers of an entrance mat in accordance with the invention.
As regards the upper layer, any textile floor covering (or similar) material
that offers the
required soil-removing characteristics can be considered, provided it is in a
form capable
of being secured to the selected lower layer of the mat. The material need not
be of tufted
construction but could, for example, be of needle-punched, flocked, or woven
construction. If the material comprises a pile layer, the pile fibers can be
of any suitable
material(s), both natural and synthetic, and of any suitable denier and
length, and may be
texturized or otherwise treated as required. Any backing materials known to be
suitable
for textile floor covering materials can be used, including woven and non-
woven backings
formed from natural or synthetic materials, provided that the backing is
either inherently
water-permeable or is perforated in some way to allow water to pass through
it. Although,
as described above, the backing for a tufted pile material will typically
comprise both a
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primary and a secondary backing, the latter can (as already indicated) be
omitted provided
that the textile is sufficiently stable to be handled without it.
Generally, the use of a textile floor covering material in the upper layer of
a mat in
accordance with the invention provides a wide degree of choice in the
appearance of the
mat and its functional characteristics. For example, a wide range of colors
and surface
patterns can be made available through selection of the pile fibers and the
carpet
construction, and use of finishing operations such as printing and embossing.
Likewise, a
wide range of functional characteristics can be made available through
selection of the pile
fibers and the carpet construction, and use of surface treatments to enhance
performance.
The presence of the lower, water-receiving layer means that the ability of the
upper layer
to retain water removed from the soles of shoes becomes less significant to
the
performance of the mat, which also increases the degree of choice in the
appearance of the
upper layer and the materials from which it is constructed.
Examples of textile floor covering materials from which the upper layer of a
mat in
accordance with the invention could be selected are described in US-A-4 045
605 (Breens
et al); WO 95/30040 (Kleentex Industries, Inc.); WO 01/90471 (Walk Off Mats
Limited);
WO 96/35836 (Minnesota Mining and Manufacturing Company); and US-A-5 662 980
(E.I Du Pont de Nemours and Company).
As regards the lower layer of an entrance mat in accordance with the
invention, any web
material that offers the required water-receiving characteristics can be
considered,
provided it is in a form capable of being secured to the selected upper layer
of the mat. In
some situations, it may be sufficient that the lower layer simply enables
water that drains
into it from the upper layer to be collected but, in other situations, it may
be preferred that
the lower layer is structured to direct the collected water to one or more
sides of the mat so
that it can be removed. Other characteristics of the lower layer, for example
its resilience,
may also affect the overall characteristics of the entrance mat. If required,
more than one
such lower layer may be provided to increase the water-collecting capacity.
The lower
layer may be an extruded structure but alternative forms are possible
including, for
example, woven, molded, embossed or corrugated structures.
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Examples of alternative web materials from which the lower layer of a mat in
accordance
with the invention could be selected are described in US-A-4 177 312; 4 212
692; 4 252
590 and 4 342 807 (Akzona). Specific examples of alternative materials are
those
available, under the trade names "ENKAMAT" and "ENKADRAIN" from Colbond
Geosynthetics Company of St. Denis la Plaine, 93128 France.
Alternative materials suitable for the water-impermeable bottom surface of a
drop-down
mat in accordance with the invention include water-impermeable foams (for
example an
SBR [styrene-butadiene rubber] foam) and durable synthetic carpet underlay
materials (for
example an underlay material made of recycled rubber granules agglomerated and
bound
with polyurethane, commercially available in thicknesses of 5 and 10 mm from
3M
Company under the trade designation "3MTM NomadTM Recessed Well Underlay").
Depending on its nature, the bottom surface may be attached to the layer above
by
adhesive or by reclosable fasteners, or it may be applied by coating or
spraying
techniques. In the case of a drop-down mat, the floor-contacting surface of
the bottom
surface advantageously has anti-slip characteristics.
Alternative methods can also be used for securing together the upper and lower
layers of a
mat in accordance with the invention, provided that they permit water to drain
from the
upper layer into the lower layer. For example, a permeable adhesive web in the
form of a
film or a non-woven material could be located between the upper and lower
layers to bond
them together. Alternatively, depending on the materials present in the
layers, it may be
possible to bond the layers together simply by applying heat to soften them.
As a further
alternative (for example, in the case in which the upper and lower layers are
both woven
structures) it may be possible to form the two layers together.
As a further alternative, the upper layer may be removably-secured to the
lower layer
using, for example, some form of reclosable fastener system such as a hook-and-
loop
fastener system, or through the provision of hooks or similar features only on
the lower
layer. In that case, the upper layer can be replaced by another for cleaning
purposes (e.g.
for washing), or simply to change the appearance of the mat. As yet a further
alternative,
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the upper layer could simply be laid on top of the lower layer provided that
there is
sufficient friction between the layers to prevent them from moving relative to
one another.
A drop-down mat in accordance with the invention can be provided, if required,
with an
edging of any suitable type that takes account of the water-receiving function
of the lower
layer of the mat. The edging may serve to contain water that collects in the
lower layer.
Suitable mat edgings include those available, from 3M Company, for use with
3MTM
NomadTM Terra matting and 3MTM NomadTM Aqua matting. In some cases, the edging
alone could serve to secure the upper layer of the mat to the lower layer.
As indicated above, the water that is received in the lower layer of a mat in
accordance
with the invention is contained for subsequent removal, either because the mat
is installed
in a recess well in the floor, or because the mat is provided with an
impermeable lower
surface and, if appropriate, a suitable edging. If the amount of water is not
large, it may
simply evaporate when the weather conditions have improved, this being
encouraged by
the provision of channels in the lower layer that permit the water to spread
out over the
area of the mat. In the case of a drop-down mat, evaporation may be encouraged
by the
provision of some form of ventilation in the edging.
If required, however, the water can be deliberately removed from the lower
layer. This can
be achieved in several ways, depending on the construction of the mat. In the
case of a mat
with an edging, for example, the edging could be designed to permit the water
to be
removed by the application of suction. In the case of a mat in which the upper
layer is
removable, access to the lower layer can readily be gained to permit the water
to be
removed, either by suction or in any other suitable way. Alternatively, water
may be
removed from the top surface of the mat using a widely available vacuum
cleaner of the
type that is suitable for removing water. If desired, an absorbent particulate
material can
be provided in the lower layer and removed in any suitable way when it has
become
saturated. In the case in which the lower layer is a non-woven material as
described above,
it has been found that water removal can be facilitated by punching apertures
through both
the backing of the upper layer and the non-woven lower layer, even when the
backing of
the upper layer is inherently water-permeable.
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It will be appreciated that material of any of the constructions described
above as being
suitable for use as a drop-down mat (i.e. having a water-impermeable lower
surface) could
also be used as carpeting in, for example, spaces such entrance lobbies in
buildings or
public transport vehicles (e.g. train carriages). The carpeting could, if
required, be
provided in wall-to-wall form and removably-secured in position with
mechanical or
adhesive fasteners.
Material of any of the constructions described above with reference to the
drawings can,
where suitable, also be used as infill material in a mat/carpet, where it
would provide a
part only of the surface area of the mat/carpet. For example, the material
could be used in
the profiles of a profile mat or in specially-adapted areas of a scraper mat.
An example of
a profile mat is the above-mentioned product available, under the trade name
"NomadTM
Optima", from 3M Company. An example of a scraper mat with specially-adapted
areas
for textile infills is a one that is formed using Nomad 8900 "scraping and
textile" tiles,
also available from 3M Company.
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