JP2023167212A - Artificial lawn - Google Patents

Abstract

To provide an artificial lawn having high impact absorption.SOLUTION: An artificial lawn comprises a warp knitted fabric 5 having a plurality of stitch rows 1, 1,.. running in the wale direction and having through-holes 4, a plurality of pile yarns 2, 2,.. rising upward from the surface of the warp knitted fabric 5 and having a top part serving as a loop part 2r, and a synthetic resin 3 which adhered without closing the through-holes 4. The loop part 2r of the pile yarn 2 is formed to pass through the loop portions of other adjacent pile yarns, whereby the plurality of pile yarns 2, 2,.. are in a connected state. The synthetic resin 3 adheres in a film shape, a puddle shape, or a ball shape to a part between the pile yarns 2, 2, ..and the part between the pile yarns 2, 2, ...is bonded.SELECTED DRAWING: Figure 3

Description

Application for exception to loss of novelty applied

The present invention relates to artificial turf, particularly temporary artificial turf, and relates to artificial turf to be laid on natural turf in stadiums, or on tracks, paths, etc. other than natural turf.

BACKGROUND ART Conventionally, as temporary artificial turf laid on natural turf, one formed of a warp-knitted fabric and pile yarns standing up from the surface of the warp-knitted fabric has been known (Patent Document 1). Athletes practice and warm up on the temporary artificial turf. However, the temporary artificial turf described in Patent Document 1 has low shock absorption properties, and if a player steps on it incorrectly or falls, there is a risk of injury during practice or the like.

Japanese Patent Application Publication No. 2001-238551

An object of the present invention is to provide artificial turf with high shock absorption.

The present invention solves the above-mentioned problems by devising the structure of the pile yarns and bonding a portion between the pile yarns with a synthetic resin. That is, the present invention provides a warp knitted fabric having a plurality of stitch rows running in the wale direction and having openwork stitches, and a plurality of piles that stand upward from the surface of the warp knitted fabric and have a ring at the top. The plurality of pile yarns are composed of a thread and a synthetic resin attached without blocking the openwork, and the plurality of pile threads are connected by forming a loop passing through another neighboring loop. The present invention relates to an artificial turf characterized in that a portion of the pile yarns are bonded with the synthetic resin.

In the artificial turf according to the present invention, the pile yarns are connected to each other near the ring, and a portion of the pile yarns are bonded with synthetic resin, so that when an impact is applied, the pile yarns are connected to each other. The impact is not only felt at the point where it was received, but also at the area around that point. Therefore, the artificial turf according to the present invention exhibits the effect of increasing shock absorption and protecting players from injury.

FIG. 3 is a schematic diagram showing a connected state of a ring according to an example of the present invention. It is a schematic diagram which showed the connected state of the ring part based on another example of this invention. It is a photograph taken of a part of artificial turf according to an example of the present invention.

The artificial turf according to the present invention is composed of a warp knitted fabric 5 having open-cut stitches 4, pile yarns 2 standing up from the surface of the warp-knitted fabric 5, and synthetic resin 3 attached without blocking the open-cut stitches 4. . The warp knitted fabric 5 can be knitted by a conventionally known method, for example, by using a Raschel knitting machine or the like. The openwork stitches 4 are formed by providing intervals between the stitch rows 1, 1, . . . running in the wale direction of the warp knitted fabric 5. The shape of the openwork 4 is generally a square (square) or a rhombus (diamond). The warp knitted fabric 5 may be any conventionally known fabric having openwork 4. For example, it may be formed only of stitch rows 1, 1, . . . and may be obtained by partially forming knots between adjacent stitch rows 1, 1. Alternatively, an insertion yarn may be inserted between the stitch rows 1, 1, . . . . In the former case, the openwork is likely to be diamond-like, and in the latter case, the openwork is likely to be square. The presence of such openwork improves water permeability, making it difficult for sprinkled water or rainwater to accumulate.

Since the artificial turf according to the present invention is provided with pile yarns 2 that stand up from the surface of the warp knitted fabric 5, it is preferably knitted using a double Raschel knitting machine. A double raschel knitting machine is a machine that knits a front warp knitted fabric and a back warp knitted fabric while connecting these two warp knitted fabrics with a connecting yarn. Using this double raschel knitting machine, for example, if you knit only the back warp knitted fabric without knitting the front warp knitted fabric, and knit a connecting yarn to this back warp knitted fabric, you can knit the back warp knitted fabric and this back warp knitted fabric. A knitted fabric consisting of connecting yarns standing up from the surface is obtained. Since the front warp knitted fabric is not knitted, the connecting yarn extending upward from the back warp knitted fabric forms a loop at the original position of the front warp knitted fabric, and becomes pile yarn 2 with this loop as the top. .

In the present invention, the loop 2r of the pile yarn 2 is formed by passing through another loop nearby, and a plurality of pile yarns 2, 2, . . . are connected. This state will be explained below based on the diagram. In FIG. 1, symbols 11a and 11b indicate stitch rows running in the wale direction of the warp knitted fabric. Although not shown, the stitch rows 11a and 11b are connected by an insertion yarn running in the course direction, or a knot formed by intersecting the stitch rows 11a and 11b every few courses is used to create a warp with open eyes. It is a knitted fabric. When there is a pile yarn 21 knitted in one stitch row 11a and a pile yarn 22 knitted in the vicinity thereof, the loop 21r of the pile yarn 21 is formed by passing through the loop 22r of the pile yarn 22. There is. Further, the loop portion 22r of the pile yarn 22 is formed through the loop portion 23r of the pile yarn 23. Furthermore, the pile yarn knitted into the stitch row 11b also has the same structure as the pile yarn knitted into the stitch row 11a. By continuing these in the front and back, the loop portion 2r of the pile yarn 2 becomes connected.

In FIG. 2, symbols 11a, 11b, 11c, and 11d each indicate a stitch row of the warp knitted fabric. In the case of FIG. 2, as in the case of FIG. 1, the stitch rows 11a and 11b are either connected by an inserted yarn running in the course direction, or have openwork by knots knitted by crossing the stitch rows 11a and 11b every few courses. It is a warp knitted fabric. The pile yarn 21 woven into the stitch rows 11a and 11c forms a loop 21r just above the stitch row 11b, and this loop 21r is formed by passing through the loop 22r of the pile yarn 22. The pile yarn 22 is woven into the stitch row 11a and the stitch row 11c, and forms a ring portion 22r just above the stitch row 11b. This loop 22r is formed by passing through the loop 23r of the pile yarn 23. The pile yarn 23 is woven into the stitch rows 11a and 11c, forming a ring portion 23r just above the stitch row 11b. Furthermore, the pile yarns knitted into the stitch rows 11b and 11d form a loop just above the stitch rows 11c, and have the same structure as the pile yarns knitted into the stitch rows 11a and 11c. . By continuing this forward and backward, the loop portion 2r of the pile yarn 2 becomes connected. In the case of Fig. 2, the pile yarn stands diagonally upward facing the course direction, and a ring is formed at the top of the pile yarn, so the standing state of the pile yarn has a truss structure, which improves shock absorption. improves.

Further, the connected state of the pile yarns 2 may be a combination of the connected states of the pile yarns 2 shown in FIGS. 1 and 2. For example, in a plurality of courses such as 3 to 7 courses, the pile yarns may be connected in a manner as shown in FIG. 1, and in a subsequent plurality of courses such as 3 to 7 courses, the pile yarns may be connected in a manner as shown in FIG. 2. 1 and 2 schematically show the structure and form of pile yarn in an easy-to-understand manner. In reality, the spacing between adjacent stitch rows is about 0.5 to 2 mm, the spacing between adjacent pile yarns is also about 0.5 to 2 mm, and the pile yarn is a flexible monofilament of about 200 to 700 decitex. It is made of thread. Therefore, the pile yarns are deformed back and forth and left and right, and the pile yarns overlap or come into contact with each other.

The height of the pile yarn 2 standing upward from the surface of the warp knitted fabric is about 5 to 15 mm. As the pile yarn 2, conventionally known yarns can be used, but it is preferable to use a highly rigid monofilament yarn. Although conventionally known yarns can be used as the yarns constituting the warp knitted fabric, it is preferable to use multifilament yarns that are easily impregnated with the synthetic resin 3. Since the pile yarns 2 are knitted into the stitch row 1 of the warp knitted fabric having openwork stitches 4, there are gaps of about 0.5 to 2 mm between the pile yarns 2, 2, . A portion between the pile yarns 2, 2, . . . is bonded with a synthetic resin 3. In order to bond the pile yarns 2, 2, the synthetic resin 3 is preferably attached in the form of a film, a web, a bead, or the like. Further, the synthetic resin 3 is preferably impregnated into the yarn constituting the warp knitted fabric and attached to the yarn surface, and also attached to the surface of the pile yarn 2. This improves shock absorption and durability.

In order to join part of the pile yarns 2, 2, . What is necessary is to fix the synthetic resin 3 by using the following steps. At this time, by adjusting the viscosity and impregnation amount of the synthetic resin liquid based on the density of the pile yarns, part of the gap between the pile yarns 2, 2, etc. The synthetic resin 3 is attached in a cross-linked form, and a portion of the pile yarns 2, 2, . . . are bonded together by the synthetic resin 3. As the synthetic resin 3, conventionally known ones can be used, and flexible or elastic vinyl chloride resin, urethane resin, acrylic resin, etc. can be used. In particular, it is preferable to use flame-retardant vinyl chloride resin. This is because artificial turf is often required to be flame retardant when used in indoor stadiums or dome-shaped stadiums. It is preferable that the synthetic resin 3 contains a pigment. Since it is artificial grass, it is preferable to contain a green pigment. Further, arbitrary additives such as inorganic fillers, flame retardants, or plasticizers may be included.

This artificial turf is used for conventionally known purposes. It is particularly suitable as temporary artificial turf, and can be laid on natural turf in stadiums, or on tracks, paths, etc. other than natural turf. Moreover, since artificial turf using vinyl chloride resin as the synthetic resin is flame retardant, it can also be used by laying it on the floor indoors.

Example 1
A polyester multifilament yarn of 330 decitex and 96 filaments was prepared as a yarn for knitting a warp knitted fabric. Further, a 455 decitex polyester monofilament yarn was prepared as a yarn for knitting a pile yarn. Using both of these yarns, a knitted fabric consisting of pile yarn and warp knitted fabric was knitted with the following knitting structure using a 14-gauge double Raschel knitting machine using reeds L3, L4, L5, and L6.
(Pile yarn structure)
L3: 2-3, 4-5/3-2, 1-0// (1in 1out)
(Warp knitted fabric structure)
L4:0-0,0-1/1-1,1-0// (All in)
L5: 3-3, 0-0/0-0, 1-1/1-1, 0-0/0-0, 3-3/3-3, 2-2/2-2, 3-3/ / (All in)
L6: 0-0, 2-2/2-2, 1-1/1-1, 2-2/2-2, 0-0/0-0, 1-1/1-1, 0-0/ / (All in)

The basis weight of this knitted fabric was approximately 500 g/m ² . The warp knitted fabric had a yarn density of 17 courses/inch and 14 wales/inch, and had open-cut stitches consisting of square stitches. The height of the pile yarn was about 10 mm, and the standing state of the pile yarn was of a truss structure.

This knitted fabric was impregnated with a vinyl chloride resin solution containing 100 parts by mass of vinyl chloride resin and 14 parts by mass of green pigment, and then heat-treated at 185° C. to obtain artificial turf. The amount of vinyl chloride resin deposited was about 700 g/m ² . Vinyl chloride resin was attached in the form of a film or the like to a portion between the pile yarns, and the pile yarns were bonded together.

Comparative example 1
The knitted fabric knitted in Example 1 without adhering vinyl chloride resin was used as artificial turf.

The impact absorption properties (%) of the artificial turf according to Example 1 and Comparative Example 1 were measured. Shock absorption (%) was measured by the AAA method (Advanced Artificial Athlete), which is an advanced test method of EN 14808. In the AAA method, a 20 kg weight equipped with an accelerometer is dropped onto artificial turf from a height of 55 mm, and the impact force (N) received by the weight is detected and calculated using the following formula.
Shock absorption (%) = [(X-Y)/Y] x 100
In the formula, X is the impact force (N) that the weight receives, and Y is the reference impact force (6760N). Here, the standard impact force is the impact force that a 20 kg weight receives when it is dropped from a height of 55 mm onto a concrete surface (20 cm thick), and a value of 6760 N is generally adopted. .

As a result of measurement using the AAA method, the impact absorption property of the artificial turf according to Example 1 was 14%, and that of the artificial turf according to the comparative example was 5%. Therefore, it can be seen that the artificial turf according to Example 1 has better shock absorption properties than the artificial turf according to Comparative Example 1.

1 Stitch row 2 Pile yarn 2r Pile yarn loop 3 Synthetic resin 4 Openwork 5 Warp knitted fabric 11a, 11b, 11c, 11d Stitch row 21, 22, 23 Pile yarn 21r, 22r, 23r Pile yarn loop

Claims (9)

A warp knitted fabric with multiple stitch rows running in the wale direction and having openwork stitches;
a plurality of pile yarns standing upward from the surface of the warp knitted fabric and having a ring at the top;
and a synthetic resin adhered without blocking the watermark,
The loops of the pile yarns are formed by passing through the loops of other nearby pile yarns, so that they are connected,
An artificial turf characterized in that a portion between the pile yarns is bonded with the synthetic resin. 2. The artificial turf according to claim 1, wherein a portion of the pile yarns are bonded by a membrane-like, web-like, or bead-like synthetic resin. 2. The artificial turf according to claim 1, wherein the warp knitted fabric is formed of a plurality of stitch rows running in the wale direction and insertion yarns connecting the plurality of stitch rows and running in the course direction. The artificial turf according to claim 1, wherein the pile yarn is woven into the stitches constituting the stitch row and stands upwardly. A pile yarn stands upward from one stitch row, and a loop of the pile yarn is formed by passing through a loop of another neighboring pile yarn standing upward from the stitch row. The artificial turf according to claim 1. A pile yarn stands diagonally upward from two adjacent stitch rows and forms a loop at the top, and the loop is a loop of another pile yarn that stands diagonally upward from the two stitch rows. The artificial turf according to claim 1, wherein the artificial turf is formed by passing through the inside of the turf. The artificial turf according to claim 1, wherein the pile yarn is a monofilament yarn. The artificial turf according to claim 1, wherein the synthetic resin is a vinyl chloride resin. The artificial turf according to claim 1, wherein the synthetic resin contains a pigment and/or a flame retardant.