JPH11313751A - Artificial lawn - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a synthetic resin-made artificial lawn being well drained, which is provided with a structure where a water drop is hardly stuck to projecting bodies. SOLUTION: A base plate part 2 and multiple projecting bodies 1 which extend upward from the part 2 are formed in the synthetic resin-made artificial lawn. In this lawn, at least a mixture of a thermoplastic resin with a silicon graft polymer is made to be a base material as a resin composition constituting the projecting body 1 and also a silicon containing rate in the base material is made to be 0.5-10 wt.%. Besides, at least a hydrophobicity resin is adopted as the base material in the resin composition constituting the projecting body and also crimp working is executed in a part or the whole of the projecting bodies.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art An artificial turf made of synthetic resin is generally known to have a structure in which natural grass-like projections are planted in a matrix on a synthetic resin substrate. However, such artificial turf has poor drainage properties as compared with tile flooring or saw-like flooring, so the artificial turf itself or the underlying ground such as concrete on which artificial turf is laid, It will be wet for a long time. As a result, the moisture remaining on the base surface is corroded, damaging the base surface or giving off odor.

Therefore, conventionally, a grid-shaped board is provided in a rectangular peripheral frame, and pillars are provided on the lower surface of the intersection of the grid-shaped bars of the board to improve drainage between the board and the ground. Artificial turf made in this way has been proposed (for example,
1-118183).

[0004]

However, in the case of the above-mentioned conventional artificial turf, the state in which water droplets adhere to the natural turf-like projections planted on the substrate for several days immediately after the rain falls. Become. Therefore, walking on the artificial turf in such a state while wearing socks or bare feet will cause discomfort due to stickiness.

The present invention has been made in view of the above circumstances, and has a structure in which water droplets do not easily adhere to a projection.
The purpose is to provide synthetic resin artificial turf with good drainage properties.

[0006]

The artificial turf according to the present invention for solving the above-mentioned problems comprises a synthetic resin artificial turf in which a substrate and a large number of protrusions extending upward from the substrate are molded. The resin composition constituting at least the protruding body has a mixture of a thermoplastic resin and a silicone graft polymer as a base material, and has a silicone content of 0.5 to 10% by weight in the base material. Things.

As the thermoplastic resin, polyethylene (ultra low density polyethylene, low density polyethylene, linear low density polyethylene, medium density polyethylene, high density polyethylene), polypropylene, ethylene-propylene copolymer, ethylene-α-olefin Copolymer, olefin resin such as ethylene-vinyl acetate copolymer, polyamide resin such as nylon 6, nylon 6.6, nylon 6,10, polyvinyl chloride resin, styrene-acrylonitrile copolymer, styrene-acrylonitrile -Polystyrene resins such as butadiene three-dimensional copolymers, other thermoplastic resins, or mixtures of these resins. In particular, it is preferable to use an olefin resin from the viewpoints of water repellency of the resin, moldability of artificial turf, and economic efficiency.

[0008] The silicone graft polymer is a polymer obtained by graft-polymerizing a silicone represented by polydimethylsiloxane to a polymer or copolymer having thermoplasticity.

The thermoplastic polymer or copolymer serving as the main chain of the silicone graft polymer includes:
Low density polyethylene, linear low density polyethylene, medium density polyethylene, high density polyethylene, polypropylene, polymethyl acrylate, polyethyl acrylate, polyester, ethylene-vinyl acetate copolymer, ethylene-methacrylate copolymer, ethylene- Ethyl acrylate copolymer and the like can be mentioned. For example, when an ethylene-vinyl acetate copolymer is used as the main thermoplastic resin, the main chain constituting the silicone graft polymer mixed therewith should also be of the same type of ethylene-vinyl acetate copolymer. It is preferable from the viewpoint of compatibility.

The silicone content in the silicone graft polymer is not particularly limited, but in the case of a commercial product,
Often about 40-60% by weight. The commercially available products include Dow Corning resin additive silicone master pellets SP-100, SP-110, and SP-30.
0, SP-310, SP-350, RESADA GP-700 manufactured by Toa Gosei Chemical Co., Ltd., and silk grafts # 150, # 210, # 310, # 610 manufactured by Nippon Unicar Co., Ltd.
# 710 and the like.

The content of the silicone in the mixture of the silicone graft polymer and the thermoplastic resin as the main component is 0.5 to 10% by weight, preferably 1 to 5% by weight.
And If it is less than 0.5% by weight, the water-repellent effect is small, and if it is more than 10% by weight, the water-repellent effect is very large, but the slip resistance is small and it is not suitable for use as a flooring material. The target strength is significantly reduced.

As described above, the mixture of the silicone graft polymer and the thermoplastic resin, which is the main material, is used as a base material by adjusting the content of silicone to 0.5 to 10% by weight.

[0013] The resin composition may be added to the above-mentioned base material, if necessary, with a weather resistance improving material such as an antioxidant, an ultraviolet absorber or a light stabilizer, or a known additive such as a pigment or an antistatic agent. Is prepared by adding

The artificial turf of the above resin composition may be molded into a unit by injection molding, or may be continuously extruded and cast into a transfer molding roll into a long shape. It may be molded.

The artificial turf thus formed has a substrate portion and a number of protrusions extending upward from the substrate portion.

Among these, the substrate portion is not particularly limited, but may be formed in, for example, a rib shape, a band shape, a plate shape, or the like. In any shape, it is preferable to provide an opening on the substrate in order to quickly drain water on the substrate downward. Also, in order to quickly drain the water on the ground surface in the horizontal direction, and to quickly dry the ground surface with air by ventilation, a pillar is provided on the lower surface of the substrate part, so that the base part and the substrate part are interposed. Preferably, a clearance is provided.

The projecting body is not particularly limited, but may be, for example, a polygonal prism such as a cylinder, an elliptic cylinder, a triangular prism or a quadrangular prism, a pyramid such as a cone, a triangular pyramid or a quadrangular pyramid, or a pseudo-turf-like. Any shape may be used, and these shapes may be mixed and formed on the substrate portion. However, a pseudo-turf-like shape is preferable from the viewpoint of aesthetics.

The artificial turf may be entirely formed of the above resin composition. However, the protruding portion may be formed of the above resin composition, and the substrate may be formed of a resin having an adhesive property with the above resin composition. May be formed of the above resin material. For example, the protruding portion can be formed from the above resin composition, and the substrate portion can be formed from a thermoplastic resin obtained by removing the silicone graft polymer from the above resin composition.

According to this artificial turf, by mixing the silicone graft polymer, the water repellency of the resin composition is remarkably improved due to the effect of the silicone in the silicone graft polymer, and water droplets hardly adhere to the surface of the projecting body. Become. In addition, for example, compared to mixing a water repellency improver such as a master batch of silicone oil, in the case of a silicone graft polymer, since the thermoplastic resin is graft-polymerized, the molecular weight is very large, Very little loss of silicone due to bleeding on the surface, so not only long lasting effect of water repellency but also good compatibility with the main material, so there is almost no decrease in physical properties such as mechanical strength . In addition, since water repellency is improved, dirt such as scale is hardly attached. further,
Silicone acts as a lubricant, and the releasability during molding is improved.

Further, the artificial turf of the present invention for solving the above-mentioned problem has at least a projecting shape in a synthetic resin artificial turf in which a substrate portion and a plurality of projecting members extending upward from the substrate portion are molded. The resin composition constituting the body has a hydrophobic resin as a base material, and a part or all of the protruding body is subjected to graining.

As the hydrophobic resin, as shown in FIG.
The water contact angle θ when the water droplet b is dropped on the surface of the resin flat plate a is 90 ° or more. As such a hydrophobic resin, for example, polyethylene (ultra low density polyethylene, low density polyethylene, linear low density polyethylene,
Medium density polyethylene, high density polyethylene) polypropylene, ethylene-propylene copolymer, ethylene-α-
Olefinic resins such as olefin copolymers, ethylene-vinyl acetate copolymers, nylon 6, nylon 6.6,
Polyamide-based resin such as nylon 6,10, polyvinyl chloride resin, styrene-acrylonitrile copolymer, styrene-acrylonitrile-butadiene three-dimensional copolymer and other polystyrene-based resins, other thermoplastic resins, or these resins Examples thereof include a mixture or a resin obtained by adding a water repellency improver such as silicone or Teflon to the above resin. The hydrophobicity of the resin itself, the moldability of artificial turf,
The use of an olefin-based resin is optimal in consideration of economic efficiency.

The resin composition is prepared by adding a weather resistance improving material such as an antioxidant, an ultraviolet absorber or a light stabilizer, or a pigment or an antistatic agent to the hydrophobic resin as a base, if necessary. It is prepared by adding additives.

The artificial turf of the above resin composition may be molded into a unit by injection molding, or may be continuously extruded and cast into a transfer molding roll to form a long piece. It may be molded.

The artificial turf thus formed has a substrate portion and a number of protrusions extending upward from the substrate portion.

Among these, the substrate portion is not particularly limited, but may be formed in, for example, a rib shape, a band shape, a plate shape, or the like. In any shape, it is preferable to provide an opening on the substrate in order to quickly drain water on the substrate downward. Also, in order to quickly drain the water on the ground surface in the horizontal direction, and to quickly dry the ground surface with air by ventilation, a pillar is provided on the lower surface of the substrate part, so that the base part and the substrate part are interposed. Preferably, a clearance is provided.

The projecting body is not particularly limited, but may be, for example, a polygonal prism such as a cylinder, an elliptic cylinder, a triangular prism or a quadrangular prism, a pyramid such as a cone, a triangular pyramid or a quadrangular pyramid, or a pseudo-turf-like. Any shape may be used, and these shapes may be mixed and formed on the substrate portion. However, a pseudo-turf-like shape is preferable from the viewpoint of aesthetics.

The artificial turf may be entirely formed of the above resin composition. However, the protruding portion may be formed of the above resin composition, and the substrate may be formed of a resin having adhesive properties with the above resin composition. May be formed of the above resin material.

As shown in FIG. 2, for example, as shown in FIG. 2, a shallow grained pattern in which the entire surface of the projecting body 1 is roughened into a grindstone, that is, a so-called honing pattern 11 And, a deep grain pattern that has been further roughened,
A so-called pear-skin pattern, as shown in FIG. 3, a line-shaped grained pattern 1 provided with line-shaped irregularities along the longitudinal direction of the protrusion 1.
2. As shown in FIG. 4, a lattice-shaped grained pattern 13 in which lattice-like irregularities are provided on the entire surface of the protruding body 1 is exemplified.
In addition, the graining may be provided on the entire surface of the projection, or may be provided on a part of the projection 1 as shown in FIGS. As shown in the figure, the protruding body 1 is bent by a hot press so that a honing pattern 11, a line-shaped line-shaped pattern 12, and a lattice-shaped line-shaped pattern 13 are formed on the surface corresponding to the front surface of the turf leaves. Is also good.

The grain depth is preferably 5 to 80 μm. When it is shallower than 5 μm, when used, the textured portions are worn away in a short period of time due to friction caused by shoe soles and the like, and the effect durability cannot be expected. Further, since the surface area is not significantly increased by the surface roughening, a remarkable effect of improving water repellency cannot be obtained.
When it is deeper than 80 μm, when a molten resin is filled in a mold as in an injection molded product, and cooled and solidified for shaping, the mold release resistance when the cooled and solidified molded product is released from the mold is reduced. It becomes very large and it is very difficult to remove the product.

The graining process can be manufactured by forming a desired graining base by sandblasting or etching on the surface of a mold for shaping the projection.

According to the artificial turf in which the protrusions are subjected to graining, the surface is roughened and the surface area is increased, so that the water repellency is improved. This phenomenon is described by Wenzel's equation.

{× cos θ = cos θ ′}: true surface area / apparent surface area θ: true water contact angle θ ′: apparent water contact angle Here, when θ> 90 °, that is, in the case of a hydrophobic surface, Since Γ> 1, θ <θ ′. That is, when the hydrophobic surface is roughened, the hydrophobicity is improved.

Further, as the surface is roughened, an air layer is trapped in the concave portion, so that the water repellency is improved. This phenomenon is explained by Cassie's equation.

Cos θ ′ = Q ₁ cos θ ₁ + Q ₂ cos θ ₂ Q ₁ , Q ₂ : ratio of components 1 and 2 occupying the surface θ ₁ , θ ₂ : true water contact angle of components 1 and 2 θ ′: apparent Water contact angle Here, assuming that component 2 is air (θ ₂ = 180 °), θ
₁ <θ ′. This equation indicates that the water contact angle becomes higher when the air layer is trapped in the concave portions of the surface irregularities.

Further, the graining reduces gloss and prevents reflection. Also, when the protruding body is a pseudo-turf-like, for example, by performing vertical stripe-shaped grain processing,
The vertical stripes look like leaf veins and the appearance is significantly improved.

[0036]

Embodiments of the present invention will be described below with reference to the drawings.

[0037]

Examples 1 to 4 The resin composition was a linear low-density polyethylene (A204J manufactured by Nippon Polyolefin Co., Ltd.).
0 parts by weight, 0.2 parts by weight of a hindered phenolic antioxidant (IRGANOX1010 manufactured by Ciba-Geigy) and 0.5 parts by weight of a hindered amine light stabilizer (CHIMASSORB 944 manufactured by Ciba-Geigy) are dry-blended into a compounded resin. On the other hand, a silicone graft polymer resin additive silicone master pellet SP-350 manufactured by Dow Corning was added so as to have a silicone content shown in Table 1.

An artificial turf and a flat plate were formed from this resin composition. The artificial turf is 305 mm x
On a 305 mm rectangular short plate-like substrate 2 having a thickness of 1.3 mm, 841 plants (29 plants × 29 plants) are planted in a matrix with a pitch width of 10.5 mm.
The pseudo-turf-leaf-like projections 1 constituting the leaf plant 3 stand upright at equal intervals on a circumference of 7 mm in diameter, and an opening 4 having a diameter of 4.5 mm is provided in the concentric circle. I have.

The length of the turf leaves of the upright projection 1 is 15 mm.
The thickness of the base is 1.2 mm, the thickness of the tip is 0.3 mm, and the distance between them is gradually reduced in the range of 1.2 mm to 0.3 mm. The width of the protruding body 1 is 2.4 mm at the base and 1.6 mm at the tip, and 2.4 m between them.
The shape is gradually reduced in the range of m to 1.6 mm. In addition, in order to improve the appearance and the cushioning property, each protruding body 1 has a height from the root of about 10 mm.
It was bent by a hot press.

A boss-shaped pillar 5 having an outer diameter of 7 mm, an inner diameter of 4.5 mm, and a height of 8 mm is provided at a lower portion of the substrate portion 2 corresponding to the same position as that of the leaf plant 3 in a matrix of 225 with a pitch width of 21 mm.
(15 × 15).

A flat plate is 6.5 cm × 6.5 cm by injection molding.
It was molded to a thickness of 7.0 mm and a thickness of 3 mm. An experiment was conducted to measure drainage and water contact angle using the artificial turf and the flat plate thus formed.

First, in the drainage test, 300 ml of water was evenly sprayed on the artificial grass sample (spraying speed: 10 m).
1 / sec), drainage L after 2 minutes from the start of watering
(Ml), and the drainage rate was calculated by the following equation (atmosphere conditions: 23 ° C., 65% RH).

Drainage ratio D (%) = L / 300 × 100 Further, the water contact angle was measured by dropping distilled water having a water droplet diameter of about 1 mm onto the above-mentioned flat plate, and using a water contact angle measuring device (Kyowa Interface Science) Manufactured by the company).

In each evaluation, the unexposed product and the sample exposed outdoors for one year were measured, and the durability of the effect of water repellency was also confirmed. In each case, the samples used for the evaluation were thoroughly washed with a neutral detergent, rinsed sufficiently with distilled water, and dried sufficiently at 23 ° C. and 65% RH atmosphere. used.

The results are shown in Table 1.

[0046]

COMPARATIVE EXAMPLES 1-4 The resin composition is a silicone-grafted polymer, Dow Corning's resin additive silicone master pellet SP-, in the resin composition of the above example.
In place of 350, a resin additive HOMOC290 manufactured by Hexachemical Co., Ltd., which is a water-repellent improver obtained by converting a silicone oil into a master batch, was added so as to have a silicone content shown in Table 1. Further, a resin composition to which such a resin additive was not added was also prepared.

Using these resin compositions, an artificial turf and a flat plate were formed in the same manner as in the above Examples, and an experiment for measuring drainage and water contact angle was performed. Table 1 shows the results.

[0048]

[Table 1]

From Table 1, it can be seen that the addition of the silicone graft polymer improved drainage due to the improvement in water repellency, and the sample exposed outdoors for one year showed the same performance as the non-exposed sample. As it was maintained, the effect persistence was also confirmed.

On the other hand, in the case where the silicone of the comparative example was made into a master batch, a large improvement in drainage was observed in the unexposed product, but the effect was significantly reduced in the exposed product. hand,
It was confirmed that the durability was poor.

[0051]

Examples 5 to 15 The resin composition of Comparative Example 4 was prepared by removing the silicone graft polymer Dow Corning resin additive silicone master pellet SP-350 from the resin composition of the above example. A corresponding resin composition was prepared. In addition, an artificial turf and a flat plate were formed from the resin composition in the same manner as in the above-described examples, and an experiment for measuring drainage and water contact angle was performed. However, the artificial turf was subjected to various graining processes shown in Table 2 on both surfaces of the protruding body constituting the leaf plant. The grain shape used corresponds to the grain number of NGK Fine Mold Co., Ltd.

Using these artificial turf and flat plate, an experiment for measuring drainage and water contact angle was performed in the same manner as in the above-mentioned embodiment. Table 2 shows the results. As a comparative example, Table 2 also shows the results when the artificial turf and the flat plate of Comparative Example 4 described above, which were not subjected to graining, were used.

[0053]

[Table 2]

From Table 2, it can be seen that according to the embodiment of the present invention,
Compared with the comparative example, it was confirmed that the water repellency was improved and the resulting hydrophobicity was improved.

[0055]

As described above, according to the first aspect of the present invention, the water repellency of the protruding body is remarkably improved, and it is difficult for water droplets to adhere, so that the drainage property is improved. In addition, since the silicone graft polymer is a high molecular weight additive, it has excellent effect persistence and little deterioration in other properties such as mechanical strength.

According to the second aspect of the present invention, the water repellency of the surface of the projection is remarkably improved by roughening the surface by graining and using a hydrophobic resin as a resin. Drainability is improved by making it difficult for water droplets to adhere.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a state where a water drop is dropped on the surface of a resin flat plate.

FIG. 2 is a partial perspective view showing a state in which a protrusion has been subjected to a honing pattern graining process.

FIG. 3 is a partial perspective view showing a state in which a projection is subjected to a graining process of a stripe-shaped grain pattern.

FIG. 4 is a partial perspective view showing a state in which a protrusion is subjected to a graining process of a lattice-like grain pattern.

FIG. 5 is a partial perspective view schematically showing the entire configuration of the artificial turf.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 projecting body 11 honing pattern (texture processing) 12 streak-like line texture pattern (texture processing) 13 lattice-like line texture pattern (texture processing) 2 substrate part

Claims (2)

[Claims] An artificial turf made of synthetic resin in which a substrate portion and a number of protrusions extending upward from the substrate portion are molded, at least a resin composition constituting the protrusions is a thermoplastic resin and silicone. A mixture with a graft polymer is used as a base material, and the silicone content in the base material is 0.5 to 1
An artificial turf characterized by being 0% by weight. 2. A synthetic resin artificial turf in which a substrate portion and a plurality of protrusions extending upward from the substrate portion are molded, wherein at least the resin composition constituting the protrusions is based on a hydrophobic resin. An artificial turf characterized by being made of wood and having a part or the entire surface of the protruding body subjected to graining.