JPH08158309A - Synthetic resin-made artificial lawn - Google Patents

Abstract

PURPOSE: To enhance the adhesion resistance against walking or prevent sand or the like from flowing out by reducing gradually the wall thickness of a leaf-shaped part planted on a base part from its root to its tip and changing the rate of change in the reduction of the wall thickness from the root to the tip at least at one location. CONSTITUTION: A leaf-shaped part 1 of a lawn-shaped molded body before the application of post work is adapted to change its rate of wall thickness from a root A to positions B and C respectively. When the leaf-shaped part 1 is bent, it is so arranged that stress may be easily concentrated at the positions B and C, thereby bending the leaf-shaped part at the positions B and C with priority. This constitution makes it possible to produce a bending part at two locations and over on the leaf-shaped part 1 and prepare a zigzag leaf-shaped part. The rate of change in the wall thickness is changed only at the tip position E from the central part of the lawn molded body 1 before the execution of post work. When bending the leaf-shaped part 1, it is so arranged that stress may be concentrated only at the position E. At this position E, a leaf-shaped part 1' is bent with priority. It is, therefore, possible to provide the leaf-shaped part 1' including many bending parts at the tip from the central part of lawn leaves.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to synthetic resin artificial grass.

[0002]

2. Description of the Related Art As an artificial turf, for example, Japanese Patent Publication No. 48-4
As disclosed in Japanese Patent No. 4721, there is a structure in which natural grass-like leaf portions are planted in a matrix on a synthetic resin base portion.

This kind of artificial turf is used in tennis, golf, baseball, gateball, artificial ski fields, other stadiums and practice fields, gardens and verandas of ordinary houses, "Chibikko Square" in parks, kindergartens, elementary schools, etc. It is widely used for rugs on the grounds and rooftops of stores.

However, the artificial turf as described above forms a turf body composed of a base portion and leaf portions integrally formed with the synthetic resin by supplying synthetic resin onto the outer peripheral surface of the forming roll. The posterior leaves will inevitably be erected vertically to the base, and therefore, in order to give a natural grass-like appearance, a post-processing step in which the leaves are bent like natural grass is required. Will be needed.

As a subsequent process, in the above-mentioned publication, a heated pressure roll is arranged on the leaf-shaped portion side of the turf molded product after molding, and the leaf-shaped portion is bent by using this pressure roll to produce a natural grass-like material. A technique for imparting the appearance of is disclosed.

[0006]

By the way, according to this type of synthetic resin artificial grass, for example, (1) when improving the sag resistance against the load from the upper surface of the grass due to walking, etc., Since it is considered that the shape where the stress is not concentrated on the grass and the grasses are easily entangled with each other is good, the leaf-shaped part where the bent part is zigzag is suitable, and (2)
In artificial turf with granular material such as sand used for golf walking paths, most of the leaf-shaped parts are buried by the filled granular material, not only the appearance deteriorates, but also the filled granular material causes weather, rain, walking, etc. In order to avoid problems such as spillage due to water leakage, a leaf-shaped part that has a bent part near the tip from the center so as to cover the upper surface of the granular body is suitable, and an artificial shape with a bent shape suitable for the application such as Grass is required.

However, the above Japanese Patent Publication No. 48-44
In the method according to Japanese Patent No. 721, although it is possible to give a natural grass-like appearance to some extent, it is difficult to accurately control the temperature of the leaf portion during pressure deformation, so the molding conditions are narrowed, and the above ( It was difficult to intentionally process the shapes like 1) and (2).

The present invention has been made in view of the above circumstances, and has a bent shape for various purposes such as improvement in settling resistance to walking and prevention of outflow of particles such as sand. The purpose is to provide artificial turf made of resin.

[0009]

In order to achieve the above object, the artificial turf of the present invention is provided with a base 2 as shown in FIG. 1 corresponding to an embodiment. The thickness of the cross section cut along a plane parallel to the direction of the leaf-like portion 1 decreases from the root toward the tip, and the rate of change in thickness reduction (AB, BC, CD) is from the root A. It is characterized by being processed into a shape that changes at least at one point (B and C) up to the tip D.

Here, the artificial turf in the present invention means a leaf portion of a synthetic resin turf molded body in which a base portion and a large number of leaf portions extending above the base portion are integrally molded like a natural turf. The artificial turf that is bent into a turf, and the turf molded body before being processed into a natural turf may be molded one by one by a batch method such as injection molding, but it is economical and molding. A molded article formed into a long shape by continuous molding is preferable because it is possible to continuously perform the steps from the processing of the leaf-shaped portion of the present invention.

Further, since the leaf-shaped portion of the turf molded body before post-processing is inevitably erected vertically to the base portion,
The leaf-shaped part is processed and deformed to be bent unevenly, giving a natural grass-like appearance. As a method of subsequent processing, a method of pressurizing and deforming a leaf-shaped portion with a pressure roll that has been heated can be mentioned, but the artificial grass is made to be in a softened state before the deformation,
After that, it is preferable to adopt a method of obtaining a bent shape by cooling simultaneously with processing deformation.

The present invention will be described in more detail below with reference to the drawings. First, as shown in FIG. 3, in the artificial grass S of the present invention, a plurality of synthetic resin base portions 2 are arranged in parallel with each other at a predetermined interval,
A product in which a large number of leaf strains 3 ... 3 are integrally molded in a matrix form between the base portions 2 and 2 is molded so as to have a natural grass appearance as a whole. Each of the leaf strains 3 is composed of a plurality of leaf-shaped portions 1.
.. The backing material 4 is joined to the back surface of 2.

The backing material 4 is provided for the purpose of preventing swelling due to thermal expansion and improving the adhesiveness to the laying surface, and its material is, for example, either thermoplastic synthetic resin fiber or glass fiber. Examples include non-woven fabrics, woven fabrics, nets, and open mesh metal screens.

Here, the shape of the leaf-like portion is preferably a shape like a turf leaf in appearance, but it is, for example, a polygonal prism such as a cylinder, an elliptic cylinder, a triangular prism or a quadrangular prism, or a pyramid such as a cone, a triangular pyramid or a quadrangular pyramid. It may be.

If the shape of the leaf-like portion is grass-leaf-like, the thickness is 0.5 mm to 3.0 mm near the root and near the tip.
The range of 0.2 mm to 1.0 mm is preferable, and especially in the vicinity of the root, 0.
It is preferably 8 mm to 2.0 mm and 0.3 mm to 0.8 mm near the tip. This is because the wall thickness near the root of the leaf is 3.
If the thickness is 0 mm or more, the appearance of turf leaves will not appear, and if the thickness near the tip is less than 0.2 mm, the strength required for use will not be obtained.

Further, regarding the rate of change in the longitudinal direction of the leaf-shaped portion, in the case corresponding to the use of (1) described above, FIG.
As shown in (b), the leaf-shaped part 1 of the turf molded body before post-processing.
However, the shape may be configured by the root portion A, the position B slightly apart from the root, the position C on the tip side from the center, and the tip portion D, and the thickness change rate may change at the positions B and C, respectively. Or, in the case of corresponding to the use of the above (2), as shown in FIG. 1 (c), only the position of E on the tip side from the center of the leaf-shaped portion 1'of the grass molded article before post-processing The shape may be such that the rate of change in thickness changes.

Furthermore, the length of the leaf portion of the present invention is required to be sufficiently longer than the wall thickness, and is preferably in the range of 5 mm to 70 mm, particularly preferably in the range of 10 mm to 40 mm.
Furthermore, the leaf-shaped portions may exist individually and independently in the base portion, or, as shown in FIG. 3 above, exist in a state in which a predetermined number of leaf-shaped portions are grouped together. It may be one that does. In this case, the size of one leaf strain is preferably 5 mm to 20 mm in diameter when the strain is circular, and particularly preferable in terms of aesthetics and durability when it is 7 mm to 12 mm.

On the other hand, the base portion may be either the strip-shaped flat plate shown in FIG. 3 or the rectangular small flat plate.
Considering productivity, workability, etc., it is preferable to use a belt-shaped base portion. The thickness of the base portion is not particularly limited, but it is necessary to have a thickness that can sufficiently maintain the standing posture of the leaf portion in the unloaded state. Further, in place of the backing material 4 as shown in FIG. 3, a large number of small protrusions or ribs are provided on the back surface of the base portion to facilitate drainage and laying down, or a linear or corrugated shape or You may provide the groove of various shapes other than that. Further, it is preferable to provide an opening for drainage in the space 5 between the base or the leaf stock or in the inner portion of the leaf stock.

Further, the distance between the plurality of leaf-shaped portions or leaf stocks planted from the base portion may be set to an arbitrary distance according to the application, but the distance is the leaf-shaped portion (or leaf stock). Are preferably arranged in a straight line or in a zigzag pattern at equal intervals. Furthermore, when the leaves (or leaf stumps) are deformed by the load applied to the artificial grass, the leaves adjacent to each other are sufficiently The distance is preferably such that they are entangled.

The apparatus used for molding the artificial grass of the present invention is, as shown in FIG.
And a texture processing device 20, and a take-up device 30 and a take-up device 40 for taking out the formed artificial turf at a line speed and cutting / winding the artificial turf at a predetermined length.

The long artificial turf molding device 10 is equipped with a resin delivery device composed of an extruder (not shown) and an extrusion head 12 arranged at the tip of the extruder, and a molding roll 11, and is molded from a nozzle of the extrusion head 12. By supplying a thermoplastic resin to the outer peripheral surface of the roll 11, the base portion and the leaf-shaped portion integrally formed with the base portion are sequentially and continuously formed in the rotation direction of the forming roll 11. The turf body formed by the elongated artificial turf forming apparatus 10 passes through the dancer roll 23 and is then supplied to the texture processing apparatus 20 for post-processing.

The texture processing device 20 is a device for post-processing the grass body into a natural grass-like state, and comprises a heating zone 22 and a press die 21. Heating zone 22 with five infrared radiators (capacity 3 kW / piece), each of which can control output, at the upper and lower surfaces of the grass.
And a press die 21 capable of temperature control.
The die 21 is activated by a hydraulic cylinder (not shown), and the clearance at the time of pressurization, the press speed, the press time, and the number of presses can be arbitrarily adjusted.

The long artificial turf molding apparatus 10 described above is used.
3, artificial turf having a shape as shown in FIG. 3, that is, a plurality of elongated base portions 2, ... Are arranged at a predetermined interval from each other, and the leaf-shaped portion 1 is provided between the base portions 2 and 2. It is possible to obtain the artificial turf S having a structure formed at a constant pitch in the longitudinal direction, and further, by the post-processing by the texture processing device 20, as shown in FIG. 4, the leaf-shaped portion 1 is formed into a natural turf-like shape. It is possible to obtain the processed artificial grass S1.

In the present invention, examples of the synthetic resin forming the leaf portion 1 and the base portion 2 include polyethylene, polypropylene, ethylene-propylene copolymer,
Olefin-based resin such as ethylene-vinyl acetate copolymer,
Polyvinyl chloride, polyvinylidene chloride, vinyl chloride resins such as vinyl chloride-vinyl acetate copolymer, polystyrene, styrene-acrylonitrile copolymer, styrene-
Styrene resin such as acrylonitrile-butadiene terpolymer, nylon 6, nylon 6.6, nylon 6
Polyamide resins such as 10 and the like, polyester resins such as polyethylene terephthalate and polybutylene terephthalate, other thermoplastic resins, and mixtures of these resins may be mentioned. It is preferable to use a system resin.

[0025]

As shown in FIG. 1 (b), the leaf-shaped portion 1 of the grass-shaped molded body before post-processing has a root portion A, a position B slightly separated from the root, and a tip side from the center of the artificial grass. Assuming that the shape is composed of the position C and the tip portion, and the rate of change in wall thickness changes at the positions B and C, when the leaf-shaped portion 1 is bent by post-processing, stress concentrates at the positions B and C. The leaf-shaped portion 1 bends preferentially at these positions B and C. As a result, the leaf-shaped portion 1 is formed with two or more bent portions, and it is possible to obtain the grass molding S1 having the zigzag-shaped leaf-shaped portion 1 as shown in FIG.

Further, as shown in FIG. 1 (c), if the shape is such that the rate of change in wall thickness changes only at the position E on the tip side from the center of the leaf-shaped portion 1'of the turf molded body before post-processing, When the leaf-shaped portion 1'is bent by the post-processing, stress is likely to be concentrated at the position E, and the leaf-shaped portion 1'is preferentially bent at this position E. As a result, as shown in FIG. In addition, it is possible to obtain the artificial grass S2 containing a large number of leaf-shaped portions 1'having a bent portion on the tip side from the center of the grass.

[0027]

EXAMPLES Examples of the present invention and the results of performance tests thereof will be described. [Example 1] This example is an example of improving the sag resistance against a load from the upper surface of the grass due to walking or the like, and a low density polyethylene resin (manufacturer: Mitsubishi Oil Chemical Co., Ltd., Grade: MS31) 1
0.2 parts by weight of a hindered phenolic antioxidant (manufacturer: Ciba Geigy Co., Ltd., grade: IRGANOX1010) as a processing stabilizer, and a hindered amine ultraviolet stabilizer (manufacturer: Ciba Geigy Co., Ltd.) as a light stabilizer. , Grade: CHIMASSORB944) 0.5
A blended resin obtained by dry blending each part by weight was used.

For molding the artificial grass, the long-sized artificial grass manufacturing apparatus 10 shown in FIG. 2 was used, and the leaf stumps 3 were planted in a matrix form with a pitch width of 10 mm between the respective base portions 2. In addition, the leaf-shaped portion 1 constituting the leaf plant 3 has eight outer diameters of 7 mm and an inner diameter of 4 mm, which are vertically erected on the root of a cylindrical leaf strain, and the length of the upright turf leaf of the leaf-shaped portion 1 is 26 mm. In addition, the thickness of the root is 1.5 mm and the thickness of the tip is 0.4 mm.The rate of change in thickness in the longitudinal direction is 8/100 between the root and 5 mm, 4/100 between 5 and 15 mm, and 15-26.
The width between the leaves is 2.7 / 100, and the width of the leaf 1 is 2.0m at the root.
m is 1.3 mm at the tip, and in the meantime, the shape is gradually reduced in the range of 2.0 mm to 1.3 mm.

Then, pressure deformation processing was performed by the texture processing apparatus 20 to obtain an artificial grass S1 having the shape shown in FIG.
However, the height of the grass after pressure deformation was set to about 22 mm, considering that a sufficient bending angle can be obtained without impairing the appearance of natural grass. [Comparative Example 1] The same shape as in Example 1 was used, except that the rate of change in the wall thickness from the root to the tip of the leaf portion in the longitudinal direction was constant at 4.2 / 100.

With respect to the above-described Example 1 and Comparative Example 2, the processing conditions of the texture processing apparatus 20 were used as parameters, and the shape after processing was the height of the lawn, the distribution of the number of bent portions, and the performance evaluation was compression resistance and sag resistance. When I measured the sex,
The results shown in Table 1 below were obtained.

However, regarding the distribution of the number of bends, among sample 25 (5x5) strains used in the performance test, 10 strains (80 turf leaves) were randomly selected, and about 10 strains, the bend portion was from the root. 14 mm or less, between 14-18 mm, 18
The number of turf leaves between ~ 26mm was counted.

The compressive deformation resistance was measured by measuring the amount of deformation under a compressive load of 0.8 kgf / cm ² , and the sag resistance was measured by measuring the grass height after standing for 24 hours at room temperature after the compression fatigue test. The rate of change was measured. The condition of the compression fatigue test is a load of 0.8.
kgf / cm ² , test speed: 0.5 Hz, fatigue limit: 10,000 times.

[0033]

[Table 1]

From the experimental results shown in Table 1, Example 1- (1)-
1- (3) can be manufactured stably compared to Comparative Examples 1- (1) to 1- (3) without the number of two or more bends being affected by the processing conditions. It was also confirmed that the sag resistance was improved. [Embodiment 2] This embodiment is an example in the case of an artificial turf containing a granular material such as sand used in a golf walking path, etc., and in Embodiment 1, the rate of change in wall thickness in the longitudinal direction is from the root to 16 mm. 5 to 100 mm, and 16 to 26 mm to 3/100 except that the shape is the same as that of Example 1, and the artificial grass S2 after further processing has a granular shape as shown in FIG. As a body, silica sand (manufactured by Miku Kaiun Co., Ltd .; No. F-4) was filled at 25 kg / m ³ so that the height of the leaf-shaped portion 1 ′ was 5 mm or more from the surface of 6 layers of the granular body. [Comparative Example 2] The same shape as in Example 2 was used except that the rate of change in the wall thickness from the root to the tip of the leaf-shaped portion in the longitudinal direction was constant at 4.2 / 100.

Regarding Example 2 and Comparative Example 2 described above, the height of the grass as the shape after processing, the distribution of the number of bent portions, and the granular material layer after the granular material was filled were treated with the processing conditions of the texture processing apparatus 20 as parameters. When the length of the leaf portion exposed on the surface was measured, the results shown in Table 2 below were obtained.

However, the distribution of the number of bends was measured by the same treatment as in Example 1.

[0037]

[Table 2]

From the experimental results of Table 1, Example 2- (1)-
2- (3), compared with Comparative Examples 2- (1) ~ 2- (3), the number of two or more bends is not affected by the processing conditions, 14 ~ 18
It was confirmed that it was possible to stably manufacture in the range of mm. In addition, in Examples 2- (1) to 2- (3), the proportion of the leaf-shaped portions exposed on the surface of the granular layer was large, and the surface layer of the granular body was covered, whereby It was confirmed that not only artificial turf having the appearance of natural turf can be obtained, but also the effect of preventing the outflow of the granular material from the surface of the granular material layer due to wind and rain or walking is improved.

The sample of Comparative Example 2- (3) had a problem that the angle of the bent portion became too large at about 90 degrees and the appearance of the artificial grass was not exhibited.

[0040]

As described above, according to the present invention,
Since the wall thickness of each leaf-shaped portion planted in the base portion gradually decreases from the root toward the tip, and the rate of change in the wall thickness reduction changes at least at one location in the longitudinal direction of the leaf-shaped portion. The position of the bent portion can be stably produced in a wide range of the texture processing conditions in the post-processing, whereby an artificial grass having a bent shape suitable for the application can be obtained.

As one example thereof, in the case of an artificial turf having a leaf-shaped portion processed into a shape in which there are at least two points where the rate of change in thickness of the turf in the longitudinal direction changes, a bent portion is formed by post-processing. It is possible to easily manufacture artificial turf that has two or more leaf-shaped parts, has an appearance similar to natural turf, but has improved settling resistance, and the resistance to the sole of the foot when walking is turf. Since it smoothly increases in proportion to the deformation of the leaves, it is possible to achieve the effect of improving the sense of stability during walking.

As another example, a leaf-shaped portion processed into a shape in which there is one position where the rate of change in thickness of the turf in the longitudinal direction changes and the change point is located from the center of the turf to the tip side. In the case of artificial turf that has, it is possible to easily manufacture an artificial turf that has a leaf-shaped portion whose bent portion is located on the tip side from the center of the turf by post-processing. Even if the body is filled, the length of the leaf-shaped part exposed from the surface of the granular layer and the angle of the bent part become large, so that not only artificial turf with a natural grass appearance can be obtained, but also wind and rain and walking The effect of preventing the outflow of granules from the surface of the granule layer is improved, and furthermore, the leaf-shaped portion in the granule layer has few bent portions, so that it is relatively easy to fill the granules and wear with the granules. It is possible to achieve the effect of reducing breakage due to.

[Brief description of drawings]

FIG. 1 is a structural view of an embodiment of the present invention, (a) is a vertical cross-sectional view showing an enlarged leaf-shaped portion, and (b) and (c) are leaf-shaped portions 1, respectively.
And FIG. 1 is a diagram showing the rate of change in the wall thickness of 1'in the longitudinal direction.

FIG. 2 is a diagram showing a schematic structure of an apparatus used for molding artificial turf according to an embodiment of the present invention.

3A and 3B are views showing the structure of an artificial turf S obtained by the long-sized artificial turf body manufacturing apparatus 10, where FIG. 3A is an external perspective view and FIG. 3B is a plan view.

FIG. 4 is an external perspective view showing the shape of the artificial turf S1 of Example 1 of the present invention.

FIG. 5 is an external perspective view showing the shape of artificial turf S2 of Example 2 of the present invention.

[Explanation of symbols]

 S Artificial grass S1 Artificial grass after post-processing (Example 1) S2 Artificial grass after post-processing (Example 2) 1 ... body

Claims (1)

[Claims] 1. A synthetic resin artificial turf formed by molding a plate-shaped base portion and a large number of leaf-shaped portions extending upward from the base portion, wherein each leaf-shaped portion has a surface parallel to the base portion. The thickness of the cut cross section is reduced from the root of the leaf-shaped portion toward the tip, and the rate of change of the thickness reduction is processed in at least one location from the root to the tip. An artificial turf made of synthetic resin.