Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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Floor-Covering Web for Sports Surfaces,
in particular Synthetic Turfs
The invention relates to a floor-covering web designed as a pile
fabric for sports surfaces, in particular a syn-~hetic tur~, with
a supporting web comprising openings and therefore being
water-permeable, pile elements secured to the supporting web and
forming the pile as well as a plastic layer arranged on the
underside of the supporting web, the plastic layer being elastic
in the direction of its thickness.
So-called synthetic turfs have gained acceptance to a
considerable e~tent as floor or ground coverings for sports
surfaces. These synthetic turfs are knitted, weft-knit, woven
or tufted textile products which are produced from plastic tapes
(ribbons) and/or plastic yarns and are in -the form of a
so-called pile fabric. The pile elements simulating the blades
of grass are mostly produced rom plastic tapes or ribbons ~hich ~ -
penetrate the supporting web and are fixed in position in this
web by a textile interlacing and/or (the latter, in particular,
in a so-called tufting abric) by a back coating of part or all
o -the surface of the supporting web by means of a plastics mass.
Since a requirement, in par-ticular, of sports surfaces laid - ~
outdoors is that the floor or ground covering is permeable to ~ -
wate~, the supporting web of known synthetic -turfs has openings,
and in the case of a partial back coating the latter does not
eliminate the water-permeability of the floor covering. Floor
coverings of the type mentioned at the outset are, however, also
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known which have a back coating over their entire surface in the
form of a plas-tic layer which is elastic in the direction of its
thickness and which can be a plastic layer made from closed-cell
foamed plastic; in order to bring about the water-permeability
of the floor covering in such a case, the back coating must be
perforated.
All these known, water-permeable floor coverings described in
the above have the disadvantage that water collecting on the
surface of the floor covering passes through the floor covering
relativèly fast and in an uncontrolled manner and the floor
covering then dries out again rela-tively quickly. It has,
however, been shown that the playing conditions of a floor
covering of the type in question, in particular of a so-called
synthetic turf, depend quite substantially on whether the
surface of the covering is somewhat damp - this results in
considerably improved playing conditions.
The object underlying the invention was to provide a
water-permeable floor covering designed as a pile fabric for
sports surfaces, in particular a synthetic turf, which
essentially has ths same advantageous properties as the known
floor coverings of the type described above but retains the
desired playing conditions for a longer time than the known
floor coverings after the surface of the covering has been
wat~red.
Proceeding on the basis of a floor covering of the type
mentioned at the outset, this object may be accomplished in
accordance with the invention in that a water storage means and
a layer are provided beneath the supporting web, this layer
causing the water from the water storage means to be transported
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back to the upper regions of the floor covering during the use
of the floor covering. It is, in particular, suggested for
accomplishing the cited object that the plastic layer of a
floor-covering web of the type mentioned a-t the outset be formed
from an open-celled foamed plastic (e.g. latex foams,
polyurethane foam, sponge rubber or the like) and a storage
layer (e.g. fiber fleeces, needlefelts, heavy woven fabric,
open-celled foams or the like) having wa-ter-storing properties
be provided on the underside of the foamed plastic layer.
Water collecting on the upper side of the floor covering when it
ra-ins or when the floor covering is watered passes throu~h the
openings of the supporting web into the open-celled foamed
plastic layer and, from there, reaches the storage layer due to
the force of gravity and/or a capillary action. This storage
layer absorbs the water until its storage volume is exhausted;
water collecting on the surface of the covering, which can no
longer be s-tored, passes through the storage layer and exits -
downwardly from the floor covering. It is then drained into the
substructure or flows laterally away over the surface o a
water-impermeable substructure. Once the rain has stopped or
wa-ter is no longer being sprayed onto the floor covering, its
surface dries out relatively quickly, e.g. due to the sun and
wind. However, when the inventive floor covering is played on,
the open-celled foamed plastic is pressed together by pressure
exerted on the surface of the covering (e.g. by the foot of a
player) and this causes the surface of the covering to be
moistened again somewhat so tha~ the desired gliding effect by
means of a film of water again results (pump and play system).
This procedure is repeated until the storage layer can no longer
fill the open-celled foamed plastic with capillary water.
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Tests on a sports surface covered with the inventive floor
covering have shown in the summer months, with the climate in
Central Europe, that the inventive floor covering remains
playable the entire day after it has been watered once, i.e. the
desired playing conditions are maintained. In comparison with
conventional floor coverings, the inventive floor covering
requires only a third to a quarter of the water otherwise needed
for watering with the known floor coverings to bring about the
same playing conditions.
The storage layer can likewise be an open-celled foamed plastic
layer. For this reason, in an inventive floor-covering web the
foamed plastic layer bringing about the pump-back effect and the
storage layer can be of the same type and even form a single
layer. In preferred embodiments of the inventive floor
covering, the stora~e layer is, however, formed from a fiber
fleece which can adhesively store a multiple of its own weight
in water. In this respect, fiber fleeces are preferred which
are made from a non-decaying material and this does, of course,
apply, in addition, to all the elements of the inventive floor
covering.
As in known floor coverings, the pile elements in preferred
embodiments of the inventive floor covering also have anchoring
feet arranged on the underside of the supporting web, whereby it
is particularly advantageous for these to be located between the
supporting web and the foamed plastic layer. In this way, the
foamed plastic layer which is, in particular, bonded to the rear
side of the supporting web serves to secure the pile elements in
an improved manner in the supporting web, and the anchoring feet
of the pile elements are covered by the foamed plastic layer and
the storage layer so that when the floor covering is laid on a
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rough surface they are not subject to the risk of being chafed
through owing to l:he floor covering being played on.
Butadiene styrene is recommended, in particular, as plas~ic for
the foamed plastic layer bringing about the pump-back effect; in
order to obtain a floor covering which can be easily and
completely recycled, supporting web, pile elements, foamed
plastic layer and storage layer in other preferred ~mbodiments
of the inventive floor covering are, however, made of the same
plastics material.
As- already mentioned, it is recommended that the open-celled
foamed plastic layer bringing about the pump-back effect and the
storage layer be bonded to the rear side of the supporting web.
In this respect, it must, however, be ensured by the type of
bonding, in particular by a correspondingly selected pattern of
a connec~ing layer, that water collec-ting on the surface of the
covering can pass through the supporting web, the foamed plastic
layer and the storage layer.
Additional features, advantages and details of the invention
result from the attached, schematic illus-tration and the
followin~ description of a particularly preferred embodiment of
an inventive floor covering; the drawing shows a section through
the floor covering designed as a tufted fabric.
The drawing shows a supporting web 10, which is a tufting base
fabric, in particular a woven fabric made from plastic tapes.
Pile elements 12 are anchored in this web; these elements are
inserted into the supporting web 10 by tufting and are formed by !'
plastic tapes. They are of an approximately U-shaped design in
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the side view and each form an anchorin~ foot 12a on the
underside of the supporting web.
A foamed plastic layer 14 is bonded to ~he underside of the
tufted fabric 10, 12; this layer consists of an open-celled
foamed plastic and is, in accordance with the invention, elastic
in the direction of its thickness. Finally, a layer of fiber
fleece 16 is bonded to the underside of the foamed plastic layer
14 and forms the inventive water-storage layer. The desired
storage capacity can be achieved and adjusted by the thickness,
density, structure and the type of fibrous material used for the
layer of fiber fleece 16.
The pores of the foamed plastic layer 14 allow a transport of
water effected by the force of gravity through the foamad
plastic layer 1~ into the layer of fiber fleece 16 and, as a
result of the capillary action or the pumping effect occurring i,~
when the floor covering is played on, back from the layer of
fiber fleece 16 into the actual syn~hetic turf layer 10, 12 and,
in particular, through its water-permeable supporting web 10 to
the surface of the synthetic turf layer. With respect to the -
water-permeability of the supporting web 10 it is to be noted
that this can be ensured and adjusted in a variety of ways, for
example by means of relatively thick needles during tufting, the
type and density o the textile material used for the production ~;
of the supporting web lO, e~g. the width of the plastic tapes
used for the production of a woven fabric and the spacings
between the warp and weft threads formed by the tapes, as well
as by the type of finishing possibly used for the supporting web
material; these are, howe~er, known measures and so a d~tailed
explanation of them is not required.
