U.S. patent application number 17/470805 was filed with the patent office on 2021-12-30 for artificial turf with textured hydrophilic fibers.
The applicant listed for this patent is 4427017 Canada Inc.. Invention is credited to Frederic VACHON.
Application Number | 20210404126 17/470805 |
Document ID | / |
Family ID | 1000005880919 |
Filed Date | 2021-12-30 |
United States Patent
Application |
20210404126 |
Kind Code |
A1 |
VACHON; Frederic |
December 30, 2021 |
ARTIFICIAL TURF WITH TEXTURED HYDROPHILIC FIBERS
Abstract
An artificial turf system for installation over a receiving
surface is described. The artificial turf system comprising: a
sheet member made of a flexible material, the sheet member defining
a first surface for interfacing with the receiving surface and a
second surface; primary yarns made of straight fibers backstitched
in and threaded through the sheet member and upwardly extending
from the sheet member to a first elevation; and secondary yarns
made of textured fibers backstitched in and threaded through the
sheet member and upwardly extending from the sheet member at a
second elevation less than the first elevation which is caused by a
difference in texture between the primary yarns and the secondary
yarns, wherein the secondary yarns are more rigid than the primary
yarns, and wherein the primary yarns and the secondary yarns have
ends which are cut after being threaded through the sheet
member.
Inventors: |
VACHON; Frederic; (Laval,
CA) |
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Applicant: |
Name |
City |
State |
Country |
Type |
4427017 Canada Inc. |
Laval |
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CA |
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Family ID: |
1000005880919 |
Appl. No.: |
17/470805 |
Filed: |
September 9, 2021 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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16551635 |
Aug 26, 2019 |
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17470805 |
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15065138 |
Mar 9, 2016 |
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16551635 |
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62130113 |
Mar 9, 2015 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
D10B 2401/063 20130101;
D10B 2401/022 20130101; D01F 6/60 20130101; E01C 13/08 20130101;
D10B 2331/02 20130101 |
International
Class: |
E01C 13/08 20060101
E01C013/08; D01F 6/60 20060101 D01F006/60 |
Claims
1. An artificial turf adapted to be installed free of infill
material, comprising: a sheet member comprising a first surface and
a second surface; first yarns made of straight fibers tufted in the
sheet member, and having a first pulled length; second yarns made
of air jet textured hydrophilic fibers tufted in the sheet member,
having a second pulled length equivalent to the first pulled
length, and having a relaxed length of at maximum 50% of the first
pulled length.
2. The artificial turf of claim 1, wherein the sheet member, the
first yarns and the second yarns sum up to the artificial turf
having a weight density of at least 2000 gram per square meter.
3. The artificial turf of claim 1, wherein the second yarns
represents a minimum of 50% of the weight density of the artificial
turf.
4. The artificial turf of claim 1, wherein chock absorption
characteristics of the artificial turf is of a value smaller than
200 G according to ASTM F355 method of testing.
5. The artificial turf of claim 1, wherein each the first yarns are
made of hydrophobic fibers, wherein the second yarns have a linear
density of between about 4500 and about 7500 deniers, and wherein
the linear density of the first yarns is lower than the linear
density of the second yarns.
6. The artificial turf of claim 1, wherein the sheet member made of
a layer of woven polypropylene and at least one extra layer made of
one of fiber glass and polyester, wherein the artificial turf
comprises a curable material to be applied to the first surface of
the sheet member, wherein the sheet member, the first yarns, the
second yarns and the curable material are heated together when
curing the curable material, wherein each the first yarns and
second yarns have a linear density of between about 4500 and about
7500 deniers, and wherein the linear density of the first yarns is
lower than the linear density of the second yarns.
7. The artificial turf of claim 1, wherein the second yarns have a
tensile strength of a minimum of about 15 N per filament.
8. An artificial turf adapted to be installed free of infill
material, comprising: a sheet member comprising a first surface and
a second surface; exclusively first yarns and second yarns, wherein
the first yarns tufted in the sheet member, and having a first
pulled length, and wherein the second yarns are made of air jet
textured hydrophilic fibers tufted in the sheet member, having a
second pulled length equivalent to the first pulled length, wherein
chock absorption characteristics of the artificial turf free of
infill is of a value smaller than 200 G according to ASTM F355
method of testing.
9. The artificial turf of claim 8, wherein chock absorption
characteristics of the artificial turf free of infill is of a value
smaller than 130 G according to ASTM F355 method of testing when
the first surface of the sheet member is installed over a padding
layer.
10. The artificial turf of claim 8, further comprising a curable
material applied to the first surface of the sheet member, wherein
the sheet member, the first yarns the second yarns and the curable
material are heated together when curing the curable material,
wherein once the curable material cured, the sheet material
undergoes a puncture process, and wherein drainage characteristics
of the artificial turf free of infill is at least 750 mm of water
per hour.
11. The artificial turf of claim 8, wherein the sheet member, the
first yarns and the second yarns sum up to the artificial turf
having a weight density of at least 2000 gram per square meter.
12. The artificial turf of claim 8, wherein each of the first yarns
and second yarns have a linear density of between about 4500 and
about 7500 deniers, and wherein the linear density of the first
yarns is lower than the linear density of the second yarns.
13. The artificial turf of claim 8, wherein the yarns of the
artificial turf comprise a mix of hydrophobic material and
hydrophilic material.
14. The artificial turf of claim 8, wherein the second yarns have a
relaxed length of at maximum 50% of the first pulled length.
15. An artificial turf adapted to be installed free of infill
material, comprising: a sheet member comprising a first surface and
a second surface; first yarns made of straight fibers tufted in the
sheet member, and having a first pulled length; second yarns made
of air jet textured fibers tufted in the sheet member, having a
second pulled length equivalent to the first pulled length, a
curable material to be applied to the first surface of the sheet
member, wherein the sheet member, the first yarns, the second yarns
and the curable material are heated together when curing the
curable material; and wherein the second yarns tufted in the sheet
member have a relaxed length of at maximum 50% of the first pulled
length prior to curing of the curable material.
16. The artificial turf of claim 15, wherein the sheet member, the
first yarns and the second yarns sum up to the artificial turf
having a weight density of at least 2000 gram per square meter.
17. The artificial turf of claim 15, wherein the second yarns are
hydrophilic textured fibers representing a minimum of 50% of weight
density of the artificial turf.
18. The artificial turf of claim 15, wherein chock absorption
characteristics of the artificial turf is of a value smaller than
200 G according to ASTM F355 method of testing.
19. The artificial turf of claim 18, wherein chock absorption
characteristics of the artificial turf is of a value smaller than
130 G according to ASTM F355 method of testing when the first
surface of the sheet member is installed over a padding layer.
20. The artificial turf of claim 15, wherein each the first yarns
and second yarns have a linear density of between 4500 and 7500
deniers, and wherein the linear density of the first yarns is lower
than the linear density of the second yarns.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation-in-part of and claims
priority from U.S. patent application Ser. No. 16/551,635 filed
Aug. 26, 2019, which is a continuation-in-part of and claims
priority from U.S. patent application Ser. No. 15/065,138 filed
Mar. 9, 2016, which is a non-provisional application of and claims
priority from U.S. patent application 62/130,113 filed Mar. 9,
2015, the specifications of which are all hereby incorporated
herein by reference in their entireties.
BACKGROUND
(a) Field
[0002] The subject matter disclosed generally relates to playing
fields and more particularly to artificial sports and amusement
playing fields. The subject matter disclosed may also relate to
artificial turf surface of all kinds (i.e., artificial sports
playing fields, artificial amusement playing fields, gymnasium
surfaces, backyard surfaces and the like).
(b) Related Prior Art
[0003] The use of artificial or synthetic turf has been growing
steadily in recent years. Artificial turf is a surface of synthetic
fibers made to look like natural grass. It is most often used in
arenas and fields for sports that were originally or are normally
played on grass.
[0004] However, it is now being used in other applications such as,
for residential lawns or landscapes, for pet areas, for child
playgrounds, for golf courses and putting greens, on roofs, decks
and patios as well.
[0005] The advantages of synthetic turf are numerous. For example,
synthetic turf does not need to be cared as much as real grass.
Moreover, synthetic turf is more durable.
[0006] There exist on the market numerous artificial or synthetic
turf systems aiming to provide improved comfort, sufficient
traction, and shock absorbent characteristics. For example, and now
referring to PRIOR ART FIGS. 1A and 1B, there is shown a regular
artificial turf system 10 which includes a sheet member 12 made of
a flexible material and a plurality (substantially straight) fibers
14 upwardly extending from the sheet member 12. The plurality of
fibers 14, which creates a carpet-like top layer, therefore
includes a series of regularly spaced apart (or equally spaced)
parallel rows of backstitches 16. For providing the shock absorbent
characteristic, straight fiber support and sufficient traction for
the desired sport to the artificial turf system 10, a plurality of
rubber granules and/or sand (not shown, such as from recycled
tires) are often disposed on the artificial turf system 10.
[0007] Even though the rubber granules and/or sand used in modern
artificial synthetic turf tend to contain lower quantities of
harmful substances, such as metal (e.g., lead and zinc), inorganic
and organic compounds, it may significantly increase health
problems for those playing/walking on it, it may significantly
increase the surface temperature above the surface covering panel
and it may lead to some other environmental problems. The infill
also becomes compacted with time affecting directly shock
absorption and traction of the artificial synthetic turf to the
detriment of the players.
[0008] As for another example and referring now to PRIOR ART FIGS.
2A and 2B, there is shown an artificial turf system without infill
100 for installation over a receiving surface (not shown). The
artificial turf system 100 includes a sheet member 102 made of a
flexible material. The sheet member 102 defines a first surface or
primary backing 104 for interfacing with the receiving surface and
a second surface 106. The artificial turf system 100 further
includes a plurality of primary yarns 108 made of straight fibers
(monofilament, parallel fibrillated or fibrillated fibers) which
are upwardly extending from the second surface 106 of the sheet
member 102 and a plurality of secondary yarns 110 made of textured
fibers or thatch fibers which are upwardly extending from the
second surface 106 of the sheet member 102. The plurality of
secondary yarns 110 are positioned on the sheet member 102 such as
to intersperse with the plurality of primary yarns 108.
[0009] The plurality of secondary yarns 110 made of textured or
thatch fibers represent less than 50% in weight (aka face weight)
of the plurality of primary and secondary yarns 108, 110 taken
together. Therefore, the straight fiber support, traction and shock
absorbent characteristics are not optimized.
[0010] The plurality of primary and secondary yarns 108, 110 which
creates together a carpet-like top layer 112 includes a series of
regularly spaced apart (or equally spaced) parallel rows of
backstitches 114, 116 tufted or knitted in straight line, in
"zigzag" or in a S pattern. The series of regularly spaced apart
parallel rows of backstitches 114, 116 include a series of
regularly spaced apart parallel rows of backstitches 114 made of
the plurality of primary yarns 108 and a series of regularly spaced
apart parallel rows of backstitches 116 made of the plurality of
secondary yarns 110, which are interspersed within the series of
regularly spaced apart parallel rows of backstitches 114 made of
the plurality of primary yarns 108.
[0011] The fact that the artificial turf system 100 combines both
the plurality of primary yarns 108 made of straight fibers and the
plurality of secondary yarns 110 made of textured or thatch fibers
provides straight fiber support and player traction to the
artificial turf system 100. However, according to this
configuration, the straight fiber support, players traction and
shock absorbent characteristic are not optimized.
[0012] There is therefore a need for improved no-infill artificial
turf system that optimizes straight fiber support, player traction
and shock absorbent characteristics and that would overcome the
above-noted drawbacks.
SUMMARY
[0013] According to an embodiment, there is provided an artificial
turf system for installation over a receiving surface, the
artificial turf system comprising: a sheet member made of a
flexible material, the sheet member defining a first surface for
interfacing with the receiving surface and a second surface;
primary yarns made of straight fibers backstitched in and threaded
through the sheet member and upwardly extending from the second
surface of the sheet member to a first elevation; and secondary
yarns made of textured fibers backstitched in and threaded through
the sheet member and upwardly extending from the second surface of
the sheet member at a second elevation less than the first
elevation defining a difference in elevation which is caused by a
difference in texture between the primary yarns and the secondary
yarns, wherein the secondary yarns are more rigid than the primary
yarns, and wherein the primary yarns and the secondary yarns have
ends which are cut after being threaded through the sheet
member.
[0014] According to an aspect, the material used for the primary
yarns is not the same material which is used for the secondary
yarns, wherein the material used for the secondary yarns is more
rigid than the material used for the primary yarns.
[0015] According to an aspect, the secondary yarns are textured,
and wherein the textured fibers comprise crimped fibers.
[0016] According to an aspect, the secondary yarns represent more
than 50% in weight of the primary and secondary yarns together.
[0017] According to an aspect, combined yarns composed of the
primary and secondary yarns are backstitched in parallel equally
spaced apart rows on the sheet material.
[0018] According to an aspect, the mass of the secondary yarns is
greater than the mass of the primary yarns.
[0019] According to an aspect, the mass of the secondary yarns is
in a range between 15,001 and 20,000 deniers.
[0020] According to an aspect, the primary yarns and the secondary
yarns have respectively a length, and wherein the length of
secondary yarns is greater than the length of primary yarns.
[0021] According to an aspect, a ratio of the second elevation over
the first elevation is smaller than 75%.
[0022] According to an embodiment, there is provided an artificial
turf system for installation over a receiving surface, the
artificial turf system comprising: a sheet member made of a
flexible material, the sheet member defining a first surface for
interfacing with the receiving surface, and a second surface; a
plurality of primary yarns being backstitched to the sheet member
at primary backstitches, with the primary yarns raising from the
primary backstitches away from the second surface to a first
elevation; and a plurality of secondary yarns defining an
underturf, the secondary yarns being backstitched to the sheet
member at secondary backstitches, wherein the secondary
backstitches are distributed in-between the primary backstitches,
wherein the secondary yarns extend from the secondary backstitches
up to a second elevation lower than the first elevation, wherein
the secondary yarns extend sideways in random directions, and
wherein the secondary yarns intertwine with other secondary
yarns.
[0023] According to an aspect, the primary yarns comprise a lower
section rising from the sheet member under the second elevation,
and wherein the underturf provides a least partial support to the
lower section of the primary yarns thereby impeding the lower
section of the primary yarns from curving, bending or crooking.
[0024] According to an aspect, the primary yarns are made of
straight fibers.
[0025] According to an aspect, the secondary yarns are made of
curved fibers.
[0026] According to an aspect, the plurality of secondary yarns
represents more than 50% in weight of the sum of the plurality of
primary and secondary yarns together.
[0027] According to an aspect, the secondary yarns are more rigid
than the primary yarns.
[0028] According to an aspect, the secondary yarns are textured,
and wherein the textured fibers comprise crimped fibers.
[0029] According to an aspect, the primary yarns and the secondary
yarns have respectively a length, and wherein the length of
secondary yarns is greater than the length of primary yarns.
[0030] According to an aspect, a ratio of the second elevation over
the first elevation is smaller than 75%.
[0031] According to an aspect, the primary yarns and the secondary
yarns have respectively a width, and wherein the width of the
primary yarns is greater than the width of the secondary yarns.
[0032] According to an aspect, the primary yarns and the secondary
yarns have respectively a thickness, and wherein the thickness of
the secondary yarns is equal or greater than the width of the
primary yarns.
[0033] According to an embodiment, there is provided an artificial
turf system for installation over a receiving surface. The
artificial turf system comprises a sheet member made of a flexible
material, the sheet member defining a first surface for interfacing
with the receiving surface and a second surface. The artificial
turf system further comprises a plurality of primary yarns made of
straight fibers upwardly extending from the second surface of the
sheet member and a plurality of secondary yarns made of textured
fibers upwardly extending from the second surface of the sheet
material and interspersed within the plurality of primary yarns.
The plurality of secondary yarns represent more than 50% in weight
of the plurality of primary and secondary yarns together.
[0034] According to an aspect, the plurality of secondary yarns are
made of textured, thatched or crimped fibers.
[0035] According to another aspect, the primary and secondary yarns
are backstitched in parallel equally spaced apart rows on the sheet
material.
[0036] According to another aspect, combined yarns composed of the
primary and secondary yarns are backstitched in parallel equally
spaced apart rows on the sheet material.
[0037] According to another aspect, the artificial turf system with
combined yarns composed of the primary and secondary yarns are
backstitched in parallel equally spaced apart rows on the sheet
material, with the rows forming a straight, S, or Z pattern.
[0038] According to another aspect, the artificial turf system with
combined yarns composed of the primary and secondary yarns are
backstitched in parallel equally spaced apart rows on the sheet
material, with a distance separating two rows being ranged between
1/16'' and 1/2''.
[0039] According to another aspect, the sheet material is
manufactured as one of a closed-weave woven, an opened-weave woven,
leno weave cross weave or non-woven material.
[0040] According to another aspect, the thickness of the sheet
member is substantially uniform and ranges between about 0.20 mm to
about 2 mm.
[0041] According to another aspect, the mass of each of the
plurality of primary yarns is ranged between about 2,000 and about
20,000 deniers.
[0042] According to another aspect, the plurality of secondary
yarns are made of textured, thatched or crimped fibers and the mass
of each of the plurality of secondary yarns is ranged between about
2,000 and about 20,000 deniers.
[0043] According to another aspect, the plurality of primary and
secondary yarns are bound to the sheet member by heat, pressure or
with Polyurethane.
[0044] According to another aspect, the primary yarns have a first
length, the secondary yarns have a second length, and the second
length is at least equal to the first length.
[0045] According to another aspect, the plurality of secondary
yarns made of textured or thatch fibers represents one of: more
than about 51%, more than about 55%, more than about 60%, more than
about 65%, more than about 70%, more than about 75%, more than
about 80%, more than about 85%, more than about 90% and more than
about 95% in weight of the plurality of primary and secondary yarns
together.
[0046] According to another aspect, at least one of a material in
which is made the secondary yarns and a process performed on the
secondary yarns render the secondary yarns more rigid than the
primary yarns.
[0047] According to another aspect, the primary yarns are made of
one of polyethylene, polypropylene, Polyamide, polyester (PET), and
a combination of polyethylene and polypropylene.
[0048] According to another aspect, the secondary yarns are made of
one of Polyamide, Polyester (PET), polyethylene, polypropylene, and
a combination of polyethylene and polypropylene.
[0049] According to another aspect, the elevation of the secondary
yarns with respect to the second surface is less than the elevation
of the primary yarns with respect to the second surface.
[0050] According to another embodiment, there is provided an
artificial turf system for installation over a receiving surface.
The artificial turf system comprises a sheet member made of a
flexible material, the sheet member defining a first surface for
interfacing with the receiving surface and a second surface. The
artificial turf system further comprises a plurality of primary
yarns made of substantially straight fibers upwardly extending from
the second surface of the sheet member and having a first elevation
with respect to the second surface, and a plurality of secondary
yarns upwardly extending from the second surface of the sheet
material, the plurality of secondary yarns having a second
elevation, lesser than the first elevation, with respect to the
second surface. The artificial turf system has the plurality of
primary and secondary yarns backstitched to the sheet material such
as each backstitch is composed of a plurality of secondary yarns
surrounding at least one primary yarn.
[0051] According to a further embodiment, there is provided an
artificial turf system for installation over a receiving surface.
The artificial turf system comprises a sheet member made of a
flexible material, the sheet member defining a first surface for
interfacing with the receiving surface and a second surface. The
artificial turf system further comprises a plurality of primary
yarns made of substantially straight fibers upwardly extending from
the second surface of the sheet member and having a first elevation
with respect to the second surface, and a plurality of secondary
yarns upwardly extending from the second surface of the sheet
material and interspersed within the plurality of primary yarns,
the plurality of secondary yarns having a second elevation, lesser
than the first elevation, with respect to the second surface. The
plurality of secondary yarns represent more than 50% in weight of
the plurality of primary and secondary yarns together.
[0052] Features and advantages of the subject matter hereof will
become more apparent in light of the following detailed description
of selected embodiments, as illustrated in the accompanying
figures. As will be realized, the subject matter disclosed and
claimed is capable of modifications in various respects, all
without departing from the scope of the claims. Accordingly, the
drawings and the description are to be regarded as illustrative in
nature, and not as restrictive and the full scope of the subject
matter is set forth in the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0053] Further features and advantages of the present disclosure
will become apparent from the following detailed description, taken
in combination with the appended drawings, in which:
[0054] FIG. 1A is a schematic showing the top surface of an
infilled artificial turf system in accordance with the PRIOR
ART;
[0055] FIG. 1B is a schematic showing the bottom surface of the
infilled artificial turf system in accordance with the PRIOR
ART;
[0056] FIG. 2A is a schematic showing the top surface of a
no-infill artificial turf system in accordance with the PRIOR
ART;
[0057] FIG. 2B is a schematic showing another side (perpendicular
to the side shown in FIG. 2A) of the no-infill artificial turf
system of FIG. 2A in accordance with the PRIOR ART;
[0058] FIG. 3 is a schematic showing the top surface of an
artificial turf system in accordance with an embodiment;
[0059] FIG. 4 is a schematic showing the side of the artificial
turf system of FIG. 3;
[0060] FIG. 5 is a schematic showing a close-up view of the
artificial turf system of FIG. 3;
[0061] FIG. 6 is a schematic showing the bottom surface of the
artificial turf system of FIG. 3;
[0062] FIG. 7 is a schematic showing a close-up view of the sheet
member of the artificial turf system; and
[0063] FIG. 8 is a schematic depicting the process of yarns through
air jet spinning process.
[0064] It will be noted that throughout the appended drawings, like
features are identified by like reference numerals.
DETAILED DESCRIPTION
[0065] In embodiments, there are disclosed artificial turf systems
for applying on receiving surfaces.
[0066] Referring now to the drawings, and more particularly to
FIGS. 3-6, there is shown a no-infill artificial turf 200 for
installation over a receiving surface (not shown) in accordance
with an embodiment. The no-infill artificial turf 200 includes a
sheet member 202 made of a flexible material. The sheet member 202
defines a first surface, or primary backing 204 for interfacing
with the receiving surface, and a second surface 206. The no-infill
artificial turf 200 further includes a plurality of primary yarns
208 made of straight fibers (substantially straight fibers) which
are upwardly extending from the second surface 206 of the sheet
member 202 and a plurality of secondary yarns 210 made of textured
fibers or thatch fibers which are upwardly extending from the
second surface 206 of the sheet member 202. Because of their curly
shape, the plurality of secondary yarns 210 position themselves
automatically on the sheet member 202 in all direction and
therefore result in surrounding the plurality of primary yarns
208.
[0067] The plurality of secondary yarns 210 made of textured or
thatch fibers represents more than 50% in weight of the plurality
of primary and secondary yarns 208, 210 taken together. More
particularly, the plurality of secondary yarns 210 made of textured
or thatch fibers may represent one of: more than about 51%, more
than about 55%, more than about 60%, more than about 65%, more than
about 70%, more than about 75%, more than about 80%, more than
about 85%, more than about 90% and more than about 95% in weight of
the plurality of primary and secondary yarns 208, 210 taken
together.
[0068] The plurality of primary and secondary yarns 208, 210 which
creates together a carpet-like top layer 212 includes a series of
regularly spaced apart (or equally spaced) parallel rows of
backstitches 214. These rows can be straight, in S or Z patterns,
tufted or knitted. According to one embodiment, parallel rows of
backstitches 214 of primary yarns 208 are alternated with parallel
rows of backstitches of 214 secondary yarns 210. According to
another embodiment, the series of regularly spaced apart parallel
rows of backstitches 214 are made of a plurality of secondary yarns
210 surrounding or with at least one or a plurality of primary
yarns 208. The combined yarn is therefore composed of both primary
yarns 208 and secondary yarns 210. Regardless of the embodiment,
the plurality of primary yarns 208 are therefore interspersed
within the plurality of secondary yarns 210.
[0069] The fact that the no-infill artificial turf 200 combines
both the plurality of primary yarns 208 made of straight fibers and
the plurality of secondary yarns 210 made of textured or thatch
fibers (more than 50% face weight of the plurality of secondary
yarns is greater than the face weight of the plurality of primary
yarns) provides improved straight fiber support, player traction
and shock absorbent characteristics to the shock absorbent surface
covering panel 200.
[0070] As shown in FIGS. 3-6, and as better shown in FIG. 6, the
no-infill artificial turf 200 includes a plurality of backstitches
214a. Each backstitch 214a similarly includes a plurality of
primary yarns 208 made of straight fibers with a plurality of
secondary yarns 210 made of textured or thatch fibers, such as to
allow the plurality of secondary yarns 210 made of textured or
thatch fibers to represent more than about 50% in weight of the
plurality of primary yarns 208 and secondary yarns 210 taken
together.
[0071] Each backstitch 214a may be separated by a backstitch
distance. The backstitch distance may range between about 1/16''
and about 1/2''.
[0072] The sheet member 202 or several sheet members used together
may include materials made of but not exclusively limited to Olefin
(Polypropylene), Polyamide (Nylon), Polyethylene Terephalate (PET)
virgin or a recyclable material, Polyestere Woven and non woven,
cordura material either 100% or combination of these materials,
manufactured in a closed-weave woven, an opened-weave woven, leno
weave cross weave or non-woven material suitable to maximize
ability to tuft, provide tuft bind of the primary and secondary
yarns, provide dimensional stability, the hardness-flexibility
ratio of the sheet member, provide penetration of the sheet by the
secondary coating which is applied to the bottom of the sheet
member and which can be made of polyurethane or latex or acrylic or
some other material suitable to ask as a binder to hold the fibers
in place to the sheet member or to allow the binding of the fibers
to the sheet member by heat, pressure or with Polyurethane.
[0073] The thickness of the sheet member 202 is normally
substantially uniform and may range between 0.20 mm to 2 mm.
[0074] The total mass (total of the mass of each filament) of each
primary yarn filament 208 may be in a range between about 2,000 to
about 20,000 deniers. The total mass of each primary yarn 208 may
be in a range between about 2,000 and about 20,000 deniers
depending on the denier per filament (DPF) and number of filaments
in the yarn. Preferably, the total mass of each primary yarn
filament 208 is ranged between about 4,000 and about 16,000
deniers.
[0075] The mass (total of the mass of each filament) of each
secondary yarn 210 may be in a range between about 2,000 and about
20,000 deniers. The mass of each secondary yarn 210 may be in a
range between about 2,000 and about 20,000 deniers depending on the
denier per filament (DPF) and number of filaments in the yarn.
Preferably, the total mass of each secondary yarn filament 210 is
ranged between about 4,000 and about 16,000 deniers.
[0076] According to an embodiment, the mass of the secondary yarn
filament 210 is greater than the mass of the primary yarn filament
208. According to an embodiment, the mass of the primary yarns is
between about 2,000 and 19,999 deniers and the mass of the
secondary yarns is between 2,001 and 20,000 deniers so long as the
mass of the secondary yarn filament 210 is greater than the mass of
the primary yarn filament 208.
[0077] According to an embodiment, the mass of each secondary yarn
210 may be in a range between 15,001 and 20,000 deniers depending
on the denier per filament (DPF) and number of filaments in the
yarn. Preferably, the total mass of each secondary yarn filament
210 is ranged between 15,001 and 16,000 deniers.
[0078] The material of the plurality of primary yarns 208 may
include polyethylene, polypropylene, Polyamide, polyester (PET),
Nylon, a combination of polyethylene and polypropylene and the
like.
[0079] The shape and construction of the plurality of primary yarns
208 may include flat face fibers, monofilament fibers, monotape
yarn and fibrillated yarn, polyfilament fibers, parallel
fibrillated or fibrillated fibers and split fibers. The primary
yarns 208 may be made from extrusion and take different shapes such
as a rectangular cross-section ribbon, diamond, horseshoe, U, V, S
shape or a flat rectangular general cross section with its shorter
sides rounded. Its cross-section may feature one or more
curved-convex projections for instance. When backstitched to the
sheet member 202, the straight (or substantially straight) primary
yarns 208 are set upwardly extending from the second surface to
simulate the blades of grass of natural grass cover.
[0080] The material of the plurality of secondary yarns 210 may
include Polyamide, Polyester (PET), polyethylene, polypropylene,
Nylon, a combination of polyethylene and polypropylene and the
like.
[0081] The shape and construction of secondary yarns 210 may
include texturized monofilament, monotape yarn and fibrillated
yarn.
[0082] According to an embodiment, the physical characteristics of
the secondary yarns 210 are selected to obtain secondary yarns 210
that are more rigid than the primary yarns 208, therefore having
the secondary yarns 210 providing the desired support while having
the primary yarn 208 providing the desired texture. These desired
physical characteristics may be commonly obtained through selection
of a more rigid material for the secondary yarns 210 than for the
primary yarns 208; that is, the material of the primary yarns 208
(selected from the list of materials disclosed herein for the
primary yarns 208) is not the same material as the material for the
secondary yarns 210 (selected from the list of materials disclosed
herein for the secondary yarns 210). Alternatively, a process
(physical or chemical) over the secondary yarns 210 modifying its
physical characteristics may be used to obtain the desired
rigidity.
[0083] The plurality of secondary yarns 210, while described herein
as textured fibers or thatch fibers, may not require, according to
one embodiment, to be textured. However, it is referred to herein
as "textured" to distinguish itself in all embodiment from the
primary "straight" yarn 208. The secondary yarns 210 may be made of
a plurality of filiform formations arranged in turfs so as to
provide a better simulation of the blades of grass of natural grass
cover. The manufacturing of secondary yarns 210 to provide the
desired shape and structure may be performed, for instance, by
means of a heat, chemical or mechanical treatment before use
through which the secondary yarns 210 are crimped. Accordingly,
second yarns 210 may consist of yarns of at least the same length
as the first yarns 208 that, when processed, result in the desired
shorter looking secondary yarns 210.
[0084] Still referring to Figs. FIGS. 3-6, and more particularly to
FIG. 4, the elevation 218 of the primary yarns 208 from the second
surface is illustrated as greater than the elevation 220 of the
secondary yarns 210 from the second surface regardless the real
length of the primary and secondary yarns 208 and 210. Thereby the
secondary yarns 210 provide the desired fiber support of the
primary yarns 208, player traction and shock absorbing
characteristics.
[0085] The tufting process of both primary and secondary yarns 208
and 210 can be performed by stitching both the primary and
secondary yarns 208 and 210 concurrently, using the same needle.
Alternatively, the primary yarns 208 and secondary yarns 210 may be
stitched separately, using distinct needles. The latter result in
parallel backstitches of primary yarns 208 and secondary yarns
210.
[0086] According to an embodiment, the tufting process includes
threading the primary and secondary yarns 208 and 210 through the
sheet member 202. Loops are thereby formed. The tops of the loops
are then cut leaving the primary and secondary yarns 208 and 210
extending from the sheet member 202 with the end of each of the
primary and secondary yarns 208 and 210 being cut.
[0087] It should be noted that while some prior art references,
such as US Application publication number 2004/0253390 by Trafford
indicate that their blades of different heights can be anchored
into the pad in any manner desired including any way shown in the
references which are listed therein, a person skilled in the art
would know that the result that they wish to achieve is not
possible by using the tufting techniques available at that time.
That is, all tufting techniques cited by references in Trafford
will cut the blades at the same height. This point is illustrated
clearly by another reference (US Application publication number
2003/0099787 by Fink) which states: "the typical machine available
for sports carpet tufting is capable of cutting only one pile
height". It is therefore not possible to have straight blades of
different heights and different flexibility as in Trafford using
conventional tufting techniques known at the time of Trafford which
require the cutting of the loops resulting from the threading of
yarn through a mat/sheet member.
[0088] According to an embodiment, both the primary and secondary
yarns 208 and 210 are cut at the same height. The secondary yarns
210 being pre-stressed, textured, crimped, curled, curved or
otherwise pre-shaped, they will return to a shorter height to form
the underturf 300 described herein and leave the primary yarns 208
extending above the underturf 300 thus higher than the secondary
yarns 210.
[0089] According to another embodiment, the loops forming the rows
of primary yarns 208 and the loops forming the rows of secondary
yarns 210 are cut using blades which are set at different heights.
The selection of the heights of the cutting blades for each row of
yarn is determined based on the desired rigidity and density for
each of the rows.
[0090] According to another embodiment, the secondary yarns 210 are
tufted in the sheet member 202 forming loops which are cut at a
given height. The resulting carpet is then tufted again with
primary yarns 208 forming loops which are cut at a given height
which is different from the given height for the secondary yarns
210.
[0091] According to another embodiment, the primary yarns 208 are
tufted in the sheet member 202 forming loops which are cut at a
given height. The resulting carpet is then tufted again with
secondary yarns 210 forming loops which are cut at a given height
which is different from the given height for the primary yarns
208.
[0092] According to an embodiment, the length of the secondary
yarns 210 is greater than the length of the primary yarns 208 while
resulting in a height of the secondary yarns 210 on the sheet
member 202 which is less than the height of the primary yarns
208.
[0093] Depending the tufting configuration selected, the tufting
gauge can vary from about 3/16'' to about 3/4''.
[0094] The no-infill artificial turf 200 as described above may
increase protection for child in playgrounds, may provide improved
players traction and shock absorbent characteristics for sport
fields of all kinds, and may reduce the surface temperature above
the panel. The plurality of secondary yarns 210 in sufficient
quantity (more than 50% in weight) render the presence of rubber
granules unnecessary to provide straight fiber support, while
provide adequate traction for players and shock absorbent
characteristics.
[0095] Referring back to FIGS. 2A-2B in comparison with FIGS. 4 and
5, the no-infill artificial turf 200, the present realization
features primary yarns 208 backstitched to the sheet member 202 at
locations, thereby defining through the backstitch interactions
between the primary yarns 208 and the sheet member 202 a plurality
of primary backstitches 302.
[0096] The secondary yarns 210 are also backstitched to the sheet
member 202 at locations, thereby defining a plurality of secondary
backstitches 304.
[0097] Accordingly, the sheet member 202 is scattered with a
plurality of primary backstitches 302 and secondary backstitches
304, thereby having secondary backstitches 304 located in the space
around the primary backstitches 302 or, in other words, having the
secondary backstitches 304 located in-between primary backstitches
302.
[0098] One should understand from the expression "scattered" and
"located in-between" that the secondary backstitches 304 may be
located in any location relative to the primary backstitches 302,
from having the secondary backstitches in rows aligned with rows of
primary backstitches 302 (see FIG. 6) to having the secondary
backstitches in a plurality of rows or random locations distributed
between primary backstitches 302, with for example the rows of
secondary backstitches 304 offset longitudinally and/or
transversally relatively to the primary backstitches 302 or
relative to neighbor secondary backstitches 304.
[0099] Referring particularly to FIGS. 4 and 5, the secondary yarns
210 are made of material having characteristics and shaped such as
the secondary yarns 210 extending from the secondary backstitches
substantially slightly upward and mainly sideward in order for the
secondary yarns 210 as a whole to generate an underturf 300, or in
other words a sub-layer of lower elevation (elevation 218) than the
top elevation 220. The underturf 300, based on characteristics
and/or shape of the secondary yarns 210 defining the underturf 300,
provides a support for the primary yarns 208 under the lower
elevation (elevation 218), thus about the primary backstitches 302.
Practically, the secondary yarns 210 provides side pressure over
the lower portion (under elevation 218) of the primary yarns 208
substantially on many (or all) directions of the primary yarns 208
such as impeding or hindering the lower portion of the primary
yarns 208 to curve, bend or crook and thereby increase the
efficient rigidity of the lower portion of the primary yarns 208
without requiring changes in the material, characteristics or
structure of the primary yarns 208.
[0100] Further, to optimize the effect of the underturf 300, the
secondary yarns 210 are configured to extend in random directions
from the secondary backstitches 304 so as to intertwine with each
other around and about the lower portion of the primary yarns 208,
providing a "cushion" surrounding the primary backstitches 302
resulting in the "cushion" hindering deflection, curvature, bending
and/or crooking of the lower portion of the primary yarns 208 as
stated before.
[0101] Further, according to a realization, the secondary yarns 210
are curved such as when backstitched to the sheet member 202 the
secondary yarns 210 raise from the secondary backstitches 304 and
extend sideways in random directions to intertwine with each other.
As a result, the lower section of the primary yarns 208 is
interspersed with the secondary yarns 210 surrounding the primary
yarns 208.
[0102] Further, according to a realization, the secondary yarns 210
intertwine with each other to form a substantially homogeneous
underturf 300, wherein homogeneous refers to performing as a
"cushion" having substantially similar characteristics over most of
the surface of the sheet member 202.
[0103] Further, according to a realization, the secondary yarns 210
are more rigid than the primary yarns 208, wherein according to
realizations, the secondary yarns 210 being more rigid is performed
through one of selection of material for the primary yarns 208 and
the secondary yarns 210, the shape of the secondary yarns 210, and
characteristics associated with the secondary yarns through one
chemical processing and physical processing of the secondary yarns
210.
[0104] Further, according to a realization, the weight of the
plurality of secondary yarns 210 represents more than 50% of the
weight of the sum of the plurality of primary yarns 208 and of the
secondary yarns backstitched to a unit of sheet member 202.
[0105] Further, according to a realization, the length of secondary
yarns 210 (when forced in a straight configuration) is greater than
the length of primary yarns 208 (when forced in a straight
configuration).
[0106] Further, according to a realization, the ratio of secondary
backstitches 304 over the total number of backstitches (summing up
primary backstitches 302 and secondary backstitches 304) per unit
of sheet member 202 is at least 50%. According to a realization,
this ratio is at greater than 50%. According to a realization, this
ratio is at least greater than 66%.
[0107] Further, according to a realization, the ratio of the number
of yarns per backstitch of the secondary backstitches over the
primary backstitches is at equal to 100%. According to a
realization, this ratio is greater than 100%. According to a
realization, this ratio is greater than about 125%.
[0108] The ratio of the lower elevation over the top elevation is
smaller than about 75%. According to a realization, this ratio is
smaller than about 60%. According to a realization, this ratio is
smaller than 50%. According to a realization, this ratio is smaller
than about 40%.
[0109] Further, according to a realization, the primary yarns 208
and the secondary yarns 210 have respectively a color, and wherein
the color of the primary yarns 208 differs from the color of the
secondary yarns 210. For instance, the primary yarns 208 have a
grass-green color while the secondary yarns 210 have a color that
includes some shade of brown to more effectively recall a natural
turf having a free grass on top and dying grass about the ground,
with the layer of dying grass supporting the free grass in a raised
position.
[0110] Further, according to a realization, the primary yarns 208
and the secondary yarns 210 have respectively a width, and wherein
the width of the primary yarns 208 is greater than the width of the
secondary yarns 210.
[0111] Further, according to a realization, the primary yarns 208
and the secondary yarns 210 have respectively a thickness, and
wherein the thickness of the secondary yarns 210 is greater than
the width of the primary yarns 208, thereby improving the support
the secondary yarns 210 provide to the primary yarns 208.
[0112] In comparison, the no-infill artificial turf system 100 of
FIGS. 2A and 2B of the PRIOR ART features secondary yarns 110
extending substantially upward from the sheet member 102 providing
no support or low support to the section of the primary yarns
having an elevation smaller than the elevation of the secondary
yarns 108. Referring particularly to FIG. 2A, the secondary yarns
110, regardless their orientations, are not adapted to intertwine
with each other to surround the primary yarns 108 and thereby
provide support to the primary yarns 108 and thus the "cushion"
discussed before.
[0113] According to a realization, the no-infill artificial turf
200 comprises only primary yarns 208 and secondary yarns 210 tuft
side by side into a sheet member 202.
[0114] According to a non-limiting preferred realization, the
primary yarns 208 are preferrable made of substantially straight
fibers of polypropylene of about 5000 deniers. The primary yarns
208 have, typically, a pulled length extending from the sheet
member 202 of between 2 and 3 inches, thus the no-infill artificial
turf 200 having a corresponding top elevation (e.g., primary
elevation 218) of between about 2 and about 3 inches.
[0115] According to a non-limiting preferred realization, the
secondary yarns 210 are preferably made of highly textured fibers
of polyamide, and more preferably nylon, wherein the secondary
yarns 210 have undergone a series of tests to ensure that they
fulfill a series of requirements that have been identified by the
Applicant as mandatory to obtain the highly textured yarns (in
opposition to textured yarns) to result in a no-infill artificial
turf 200 fulfilling desired requirements without the necessity to
add infilled to the artificial turf system 100.
[0116] According to a manufacturing perspective, the secondary
yarns 210 are hydrophilic fibers, preferably nylon, having
undergone a texturing process, and preferably an air jet processing
under controlled environment, wherein the resulting yarn is a
highly textured hydrophilic yarn having improved characteristics
that none of a hydrophobic fiber having undergone a similar process
or a hydrophilic fiber having undergone another texturing process,
such as a knit-deknit process, would result in a fiber having
similar characteristics.
[0117] Accordingly, the nylon of the secondary yarns are highly
textured in preparation of its use in the manufacturing of the
no-infill artificial turf 200. An air jet spinning process is used.
It is a pneumatic method which consists of passing a drafted strand
of fibers through one or two fluid nozzles located between the
front roller of a drafting system and a take up a device (see FIG.
8 for example). This has been shown to be superior to methods
employing a single nozzle to spin the yarn.
[0118] For teaching purposes, the air jet spinning may be described
as follow. The drafting system drafts the input material into a
ribbon-like form with parallel fibers. Air is injected into the two
nozzles at high pressures, which cause swirling air streams in
opposite directions.
[0119] Sliver is fed into the machine and is further drawn out to
the final count and twist is inserted by means of a rotating vortex
of high pressured air. The resultant yarn is cleared of any defects
and wound onto packages ready for use in fabric formation.
[0120] Some fibers, particularly those at the edges of the ribbon,
will not be subjected to the full twisting action imparted to the
main body of fibers by the downstream air-jet. Hence they receive
less twist than those fibers in the main bundle. When the yarn gets
untwisted in the downstream of the twister, the low twist edge
fibers get untwisted to a greater degree than their original twist.
Therefore they are given a true twist in the direction opposite to
that of the upstream twist.
[0121] The main body of the strand will be untwisted into parallel
fibers, forming the core and these will be wrapped around by the
edge fibers forming the wrapper fiber layer or the sheath, thus
forming a fasciated yarn.
[0122] The function of the back nozzle is to enhance the cohesion
of the strand thus giving greater yarn strength. Since the
direction of airflow in the back nozzle is opposite to that of the
front nozzle, the back nozzle tends to untwist the wrapper fibers
as they are formed inside the front nozzle. This increases the
length of wrapping, thus improving the yarn cohesion.
[0123] The air-jet spun yarn consists of an untwisted core of
parallel fibers and a surface wrapping of fibers. The core fibers
account for approximately 85-95% of the yarn mass. The surface
wrapper fibers are helical in nature unlike the wrapper fibers in
the rotor yarn.
[0124] The wrapper fibers are not uniformly distributed over the
length; sometimes they are more on the surface and sometimes very
few are on the surface. Their frequency and tightness being
influenced by the fiber physical properties and the spinning
process parameters. "The high level of constriction of the straight
core fibers by the surface wrapper fibers results in high bending
modulus of air-jet yarns".
[0125] The tensile strength is lower than that of rotor and ring
yarns. More wrapping turns give better yarn strength, but at the
same time, higher wrapping frequency leads to higher bending
rigidity and lower compressive softness.
[0126] The untwisted core fibers contribute to the very low
snarling tendency of the air-jet spun yarns. Surface fibers twisted
lightly around the core cause the yarn to be well suited for use as
filling in air-jet weaving machines, as it can be propelled across
the shed more quickly. The lack of twist in the air-jet yarn core
is believed to contribute to the low pilling propensity of these
yarns.
[0127] The pills can still be created from abrasion, but they are
not locked into the structure because of the absence of the twist.
Pills break away easily after they are formed. Also, it has been
shown that as the number of the core fibers increases, the
proportion of the protruding fibers is reduced, resulting in lower
yarn hairiness.
[0128] According to realization, the air-jet textured yarn may be
subject to further processing before being tufted in the sheet
member 202.
[0129] Furthermore, as explained in
https://core.ac.uk/download/pdf/288373235.pdf, the process of
texturing the yarns using an air-jet process allows to obtain
textured yarns with texture characteristics determined by the
instability, linear density, and strength, together with structural
properties such as loop size, loop frequency, and degree of
entanglement, that may not be obtained with a method such as the
knit-deknit process of Auguste.
[0130] The typical yarn properties exhibited by the air jet
textured yarns are good tenacity, good evenness, low snarling
tendency, and low tendency to pilling, high stiffness, and high
shrinkage. Such properties allow the air jet textured nylon to be
used for the secondary yarns 210 to be tufted in the sheet member
202 with primary yarns 208 to form a no-infill artificial turf 200
wherein the secondary yarns 210 provide the necessary support to
the primary yarns 208 to avoid the necessity to add infill to the
yarns 208 and 210 to obtain the desired no-infill artificial turf
200.
[0131] It is worth noting, as stated in the article Air Jet
Texturising--A Versatile Process of Texturising by M. Y. Gudiyawar
Neha Hinge, The Textile Review, January, 2012, that:
[0132] "Air textured yarn is very bulky with permanent crimps and
loops. Interlacing of filaments in the jet can cause the loops to
be locked into the yarn, so that twist is unnecessary. Loop
frequency, loop dimensions, loop stability and physical bulk are
the important characteristics of air jet textured yarns.
[0133] Yarns produced by the air-jet texturising are totally
different structures in that they much more closely simulate spun
yarn structures. Whereas the bulkiness of the stretch yarns
decreases with the degree of the tension imposed on them, the form
of air-textured yarns can be made to remain virtually unchanged at
loads corresponding to those normally imposed in fabric production
and during wear. This is due to the locked-in entangled loop
structure attributed to air jet textured yarns."
[0134] Further, by controlling process parameters, and particularly
the overfeed, fibers of polyamide may be subject to air jet
texturing to obtain the desired characteristics for the secondary
yarns 210 fulfilling the requirements for the no-infill artificial
turf 200.
[0135] Accordingly, the hydrophilic fibers are air jet textured
while the knit-deknit process as known nowadays and as described in
Auguste (U.S. Pat. No. 6,321,427) teaches the use of an autoclave
to heat the fibers with the autoclave set at temperature of between
about 230- and 290-degrees Fahrenheit. Such knit-deknit process
does not provide the desired results.
[0136] The secondary yarns 210 are of over 5000 deniers and
preferably about 6000 deniers. The secondary yarns 210 consist in
yarns, when pulled and stretched, that are of about the same length
as the primary yarns 208. Once cut at an equivalent height of the
primary yarns 208, they retract into their normal relaxed length of
about 40% of their original length. According to realizations, the
relaxed length of the secondary yarns 210 is at most 75%,
preferably at most 60%, and preferably at most 50%, and even more
preferably about 40% of its pulled length.
[0137] It is to be noted that the secondary yarns 210 are tested
for extension and restauration characteristics before use.
Acceptable secondary yarns 210 for this purpose must fulfill a test
with the yarns being classified in highly textured yarns. For the
present description, textured yarns according to industry standards
are fibers that, according to a modified ASTM D4031 method, wherein
the yarns are imposed a standard weight and are calculated a value
of bulk shrinkage of at most 15%. Highly textured yarns are yarns
that according to the same testing method are calculated a bulk
shrinkage of at least 20%, and preferably at least 25%, and more
preferably about 30%.
[0138] The resulting no-infill artificial turf 200 further
undergoes a compression test of the yarns 208 and 210 tufted to the
sheet member 202 undergoing a compression from 12 mm to 10 mm with
a mass of 22 kg (2.2 kg per square mm) placed over the no-infill
artificial turf 200.
[0139] Accordingly, the present no-infill artificial turf 200
fulfils the following standard tests without the use of infill
material, while these tests require for other artificial turfs the
use of infill material and/or the use a padding layer to be within
acceptable limits. These tests are:
[0140] 1. A chock absorption (Gmax, aka slow down rate in n-times
the gravitation acceleration) with the no-infill artificial turf
200 mounted directly on a receiving surface (without the use
between the receiving surface and the no-infill artificial turf 200
of a padding layer such as the padding layer described in U.S. Pat.
No. 8,858,349 from the Applicant) of less than 200 G according to
the testing method ASTM F355, and even closer to 190 G, and with
such an padding layer a result of between 80 and 130 G, which is
about the chock absorption of a natural turf in the ideal
conditions (between 90 and 110 G).
[0141] 2. Force reduction according to ASTM F3189 of more than 50%
without the use of any infill material and any padding layer.
According to realizations, the measure of force reduction may be up
to 52%, and even up to 54-55%.
[0142] 3. Bulk test according to ASTM D4031 requiring a result of
over 30%. According to realizations, the test result is over 30%
and more preferably over 40% and may even result to about 50%.
[0143] The secondary yarns 210, when made of nylon, are designed to
provide a tensile strength (measured according to ASTM D2256-06) of
about 15 N per filament.
[0144] The primary yarns 208 and secondary yarns 210 are tufted
side-by-side to a sheet member 202 on which, after the tufting, the
opposed side, aka the underside, the underside is processed with a
curable material, e.g., urethan, and with heat applied to the
underside to cure the urethan to the underside. The underside is
slowly heated over a conveyor with a heat temperature that is
preferably under 85 degrees Celsius.
[0145] The density of the resulting no-infill artificial turf 200,
without the addition of infill, is at least 2000 gram per square
meter, and preferably about 2200 gram per square meter, resulting
in a no-infill artificial turf system 100 able to remain stable and
in place regardless of the external forces undergone as long as the
external forces are within the range of normal use.
[0146] Th drainage characteristics of the no-infill artificial turf
200, with draining punctures made over the sheet member 202, is of
at least 500 mm of water per hour according to method EN 12216,
without affecting negatively other characteristics of the no-infill
artificial turf 200 (see tests discussed before). According to
realizations, the absence of infill material combined with the
characteristics of the yarns 208 and 210, and of the sheet member
202, provide drainage characteristics of more than 750 mm of water
per hour, more than 1000 mm of water per hour, more than 1500 mm of
water per hour, and that can even reach 2000 mm of water per
hour.
[0147] According to a preferred realization, the sheet member 202
is made of a combination of at least two layers, one of woven
polypropylene, and another of one of glass fiber or of polyester,
wherein the combination provides the desired characteristics
comprising stability within a desired range to face temperature
drops and temperature increases. According to a realization, the
sheet member 102 comprises more than two layers, wherein the extra
layers are made of any of the before listed materials.
[0148] As a result, the no-infill artificial turf 200 resulting
from that process may fulfill all the requirements for sports field
use without the use of infill material. The no-infill artificial
turf 200 may further be installed directly on a receiving surface
and fulfill the requirements, or may optionally be installed over a
under padding to obtain a rate of chock absorption of a system that
very closely mimics the characteristics of natural turf.
[0149] Therefore, according to a realization, of the no-infill
artificial turf 200 is installed on a gravel surface, another
natural surface, or a concrete surface.
[0150] According to other realizations, the no-infill artificial
turf 200 is installed over a under padding layer itself previously
installed over one of a gravel surface, another natural surface, or
a concrete surface, where drainage characteristics are designed to
match the drainage characteristics of the no-infill artificial turf
200 when installed outdoor.
[0151] It is worth noting that, according to a preferred
realization, the no-infill artificial turf 200 comprises a
compilation of hydrophobic material for the primary yarns 208 that
are extending the highest, and of hydrophilic material for the
secondary yarns 210.
[0152] While preferred embodiments have been described above and
illustrated in the accompanying drawings, it will be evident to
those skilled/in the art that modifications may be made without
departing from this disclosure. Such modifications are considered
as possible variants comprised in the scope of the disclosure.
* * * * *
References