JPH0483007A - Artificial lawn sand, manufacture thereof, and artificial lawn structure using the same - Google Patents

Abstract

PURPOSE:To improve performance by adding a specified quantity of a blocking preventing agent and a resin aqueous emulsion having a specified resin solid component to a sand raised in temperature to a specified temperature to partially adhere a specified quantity of the resin to the sand, and charging it into a lawn mesh. CONSTITUTION:A cross-linking resin aqueous emulsion having 0.5-5 wt.% to sand of a resin component is provided. A blocking preventing agent consisting of 0.001-5 wt.% to sand of a higher fatty acid or its salt is provided. Then, the resin aqueous emulsion and the blocking preventing agent are added to a sand 1 dried and raised in temperature to a temperature of 100-15O deg.C while stirring in a mixer, and 0.05-5 wt.% to the sand of a resin 2 is partly adhered thereto. The resulting sand is spread into the lawn mesh of an artificial lawn structure body in a determined thickness. Thus, cushion property and softness can be given to the ground to prevent injuries of a foot and the waist.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to an artificial lawn sand that provides a ground with excellent cushioning properties, compression durability, and flexibility, a method for producing the same, and an artificial lawn structure made from the sand. .

[Prior Art] It has been known to spread sand within the grain of an artificial lawn for use as a sports field.

It is also known to spread elastic resin particles or sand uniformly coated with an elastic resin into the turf of an artificial lawn.

[Problems to be Solved by the Invention] However, in the artificial lawn ground in which such elastic resin uniformly coated sand is spread, the filling becomes fine and the porosity is low, and as a result,
The drawbacks were that the cushioning properties were poor, the surface hardened quickly, and the elasticity retention period of the gland surface was short and insufficient.

In view of the drawbacks of conventional artificial lawns containing sand, the present invention aims to provide sand for artificial lawns that can provide a flexible ground that has excellent cushioning properties and is less prone to surface hardening. be.

[Means for Solving the Problems] The present invention achieves this object with the following configuration.

That is, the artificial lawn sand of the present invention has an amorphous resin partially attached to the sand surface, and the amount of the resin attached is in the range of 0.5 to 5% by weight based on the sand. It is characterized by this.

In addition, the method for producing artificial lawn sand of the present invention has a
A film of the resin is partially attached to the sand by applying an aqueous resin emulsion to the sand in the presence of an anti-blocking agent while stirring the sand that has been dried and heated at a temperature of 50°C in a mixer. It is characterized by allowing

Further, the artificial lawn structure of the present invention is an artificial lawn structure in which the grass grains are filled with sand, and the sand is characterized in that a resin is partially attached to the surface of the artificial lawn structure. be.

[Function] Conventionally, there is a technology in which the surface of sand is uniformly coated with a resin film and filled into the grain of artificial grass, but even if such technology is adopted, the cushioning properties are still insufficient. All I got was something.

The present invention has been made as a result of intensive investigation into the problems of the prior art, and it has been found that the adhesion state of the resin coating has an important effect.

That is, the present invention was completed by investigating the fact that when the resin is partially attached to the sand surface, preferably in the form of protrusions or lumps, extremely high cushioning properties are provided.

The present invention will be explained with reference to the drawings.

FIG. 1 is an enlarged photographic diagram showing an example of the particle structure of the sand for artificial lawns of the present invention. FIG. 2 is a schematic diagram of FIG. 1.

In FIG. 2, 1 is the sand body, and 2 is the resin partially attached to the sand surface.

FIG. 3 is an enlarged photograph showing the particle structure of sand (Comparative Example 1) uniformly coated with a resin coating outside the scope of the present invention.

Comparing FIGS. 1-2 with FIG. 3, it can be seen that the way the resin is attached is clearly different. That is, in the sand of the present invention, the resin 2 is partially attached to the surface of the sand 1, preferably in the form of protrusions or lumps.

In the sand of the present invention, the adhesive thickness of the resin is preferably about 3% or more, more preferably 4 to 15%, based on the particle size in the adhesion direction, which provides a good balance between cushioning properties and durability. good.

Such a resin has excellent flexibility and flexibility, and more preferably a resin having rubber elasticity has excellent cushioning properties.

Such resins include, for example, SBR series, NBR series, C
Synthetic rubber and natural rubber such as R type and chloroprene type, acrylic resin, polyethylene-vinyl acetate type copolymer resin,
Polyethylene-vinyl acetate-vinyl chloride copolymer resins, vinyl acetate-vinyl chloride copolymer resins, vinylidene-acrylic copolymer resins, urethane resins, and the like can be used, but are not limited to these.

In the present invention, such resins may be used as they are, but using resins that are further crosslinked, vulcanized, or modified to self-crosslinking type provides sand with excellent cushioning properties and durability. preferable.

The crosslinking agents and vulcanizing agents mentioned above differ depending on each resin, but commonly used agents include sulfur, zinc white, magnesium oxide, organic peroxide, sardine compounds, melamine compounds, and epoxy compounds. The one that is available will be used. In addition, such a composition may further contain a drug such as an anti-aging agent that is normally blended into rubber.

Further, as the self-crosslinking resin, for example, those modified by introducing a functional group such as a carboxyl group or a methylol group into the above-mentioned various resins can be used.

For example, a modified resin in which carboxyl groups are introduced into SBR, methylolmelamine, etc. can be used.

In the present invention, such resin is prepared as an aqueous dispersion (emulsion).
used in the form of This aqueous resin emulsion forms a film partially on the surface of the sand, but the resin solution cannot form a uniform film and achieve the effects of the present invention.

Further, a filler can be further added to the aqueous resin emulsion, thereby making it possible to form an even stronger film. As such fillers, for example, calcium carbonate, aluminum hydroxide, carbon, clay, etc. can be used.

Further, when the sand is to be colored, the resin coating can be colored using ordinary pigments and dyes.

The aqueous resin emulsion of the present invention preferably contains a wax and a lubricating agent such as the anti-blocking agent described below, preferably in the range of 0.01 to 5% by weight, more preferably 1 to 3% by weight, in order to control the tackiness. It is better to contain a sexual substance. Such slippery substances act synergistically with the antiblocking agent to contribute to partial adhesion of the resin, and both remain in the adhering resin.

The amount of the resin attached is 0.0% based on the weight of the sand.
A range of 5 to 5% by weight, preferably 1 to 3% by weight is preferable in order to satisfy the above-mentioned resin adhesion thickness.

There are no particular restrictions on the particle size of the sand, but for ground use, sand with a size of 0.15 to 1.7 mm (100 to 10 mesh) is preferably used.

Next, an example of the method for manufacturing artificial lawn sand of the present invention will be described.

First, sand is heated to 110 to 140°C with hot air heated to 300 to 500°C while stirring to dry and preheat.

The heated sand is then transferred to a mixer and mixed with the aqueous emulsion of the resin while being stirred, and an antiblocking agent is added and mixed therein.

The mixer at this time is preferably 100 to 40
It is good to use a speed of 0 rpm, more preferably 100 to 20 Qrpm, to partially adhere the resin film. If the rotation is too fast, the resin coating will be easily broken and the sand will be crushed. If the rotation is too slow, the sand will tend to stick together (and in any case, the specific effect of partially adhering will be achieved. I can't do it.

The aqueous resin emulsion has a resin solid content of preferably 0.5 to 5%, more preferably 1 to 5%, based on the weight of the sand.
Granted within the range of 3%.

Also, the antiblocking agent is preferably 0% against sand.
．． 0.01 to 5% by weight, more preferably 0.02 to 0.1
They are mixed in a range of % by weight.

Such anti-blocking agents include, for example, higher fatty acids and their salts, such as stearic acid and calcium salts, lead salts, and zinc salts of stearic acid, waxes such as polyethylene wax and paraffin, esters of fatty acids and polyhydric alcohols, or portions thereof. Esters, fatty acid amides, fatty acid ketones, etc. can be used. Among these, higher fatty acids and their salts are effective and excellent.

Such an anti-blocking agent acts synergistically with the wax that has been mixed in the resin in advance to bias the resin adhering to the sand surface.

The mixer described above can be heated if necessary. This heating may be carried out at a temperature necessary for crosslinking or vulcanization, and in some cases it may be at room temperature, but is preferably 88°C.
A temperature of 0° C. or higher is applied. By using such a specific mixer, the resin is an aqueous emulsion;
Preferably, the resin can be advantageously partially attached to the sand surface due to the synergistic effects of the crosslinked type, the agitation, and the presence of wax or antiblocking agent.

The artificial lawn structure of the present invention is obtained by filling the grains of an artificial lawn with such artificial lawn sand.

There are no particular restrictions on the amount of sand packed, but it is preferably at least 30% by weight, more preferably 50% by weight of the total sand filling.
It is preferable to contain more than % by weight in order to utilize the functions of the sand. Such sand can of course be used by mixing it with other sands, or it can be used by filling it in layers.

The ground made of such an artificial lawn structure has a high porosity and exhibits excellent cushioning properties and flexibility because the resin is partially attached and the ground is amorphous.

[Example] The present invention will be explained below with reference to Examples.

Example 1.2, Comparative Example 1.2 A base is made of asphalt, and a polyp is placed on top of it. An artificial lawn made of nylon film splint yarn with a pile length of 19 mm and made of Pirene Genpei textile was laid.

The following sand was spread within the grain of this artificial lawn to a thickness of about 16 mm to form a ground.

First, 10 kg of sand (particle size 0.3 to 1.2 mm) was heated to 130°C in a dryer, and then transferred into a mixer rotating at a constant speed of 130 rpm to form self-crosslinking modified 5B.
R(7) 46% aqueous emulsion (0.
2 kg) was added and mixed to the sand being stirred, and after no more water vapor was released, 5 g of calcium stearate was further added and mixed.

The resin coating amount of the obtained sand was 2% by weight, and as shown in FIG. 1, an amorphous resin was adhered to the surface, and the resin adhesion thickness was about 9%.

As Example 2, resin-attached sand was produced in the same manner as in Example 1 except that instead of the SDR of Example 1, a normal 5DR 46% aqueous emulsion having no functional groups was used. Similar to Example 1, this sand was also sand to which resin was partially attached.

As Comparative Example 1, resin-bound sand was formed in the same manner as in Example 1, using a 46% resin solution in which SBR was dissolved in toluene, but without using an antiblocking agent. This sand is
As shown in FIG. 3, the particle image was whitish and uniformly covered with a resin film.

As Comparative Example 2, ordinary sand was prepared.

Table 1 shows the results after three months of practical use of the ground using these various sands.

As is clear from Table 1, the product of Example 1 had excellent cushioning properties and flexibility even after 3 months, but the product of Example 2 had excellent cushioning properties and flexibility even after 3 months, but since the product of Example 2 was not a cross-linked resin, it The functionality was at the same level as in Example 1, but after 3 months, the SBR fell off and was crushed into fine pieces, reducing the flexibility of the gland, as shown in the table.

Compared to these Examples, Comparative Examples 1 and 2 showed significantly inferior results.

Cushioning properties in Table 1: Evaluation was performed by measuring the maximum acceleration (G) according to JIS Z-0235 "Dynamic compression test method for cushioning materials for packaging".

In other words, a square (20 x 20 cm) steel load weighing 3 kg with a built-in accelerometer is held with a magnet.
The sample sand was allowed to fall 30 cm below onto a support stand on which the sample sand was placed, and the impact received by the load was converted into maximum acceleration for evaluation. The sample sand was spread in a steel box with a constant thickness of 15 mm.

Flexibility: Evaluated by measuring compressive stress based on JIS A-1216 "Unconfined compression test method for soil" (unit:
kg/crl').

[Effects of the Invention] The present invention provides sand for providing a ground with excellent cushioning properties and flexibility, and exhibits an excellent effect of not hurting the feet or lower back due to appropriate slippage and cushioning properties.

[Brief explanation of the drawing]

FIG. 1 is an enlarged photographic diagram showing an example of the particle structure of the sand for artificial lawns of the present invention. FIG. 2 is a schematic diagram of FIG. 1. FIG. 3 is an enlarged photograph showing the particle structure of sand having a uniform resin coating obtained in Comparative Example 1. 1: Paper body 2: Resin patent applicant Higashi Shi Co., Ltd. 1st t! 1

Claims (8)

[Claims] (1) Irregularly shaped resin is partially attached to the sand surface,
Sand for artificial lawns, characterized in that the amount of the resin attached is in the range of 0.5 to 5% by weight based on the sand. (2) The artificial lawn sand according to claim (1), wherein the resin contains an antiblocking agent. (3) The artificial lawn sand according to claim (2), wherein the antiblocking agent is a higher fatty acid or a salt thereof. (4) By applying an aqueous resin emulsion to the sand in the presence of an antiblocking agent while stirring the sand that has been dried and heated at a temperature of 100 to 150°C in a mixer, a film of the resin is formed on the sand. A method for producing artificial lawn sand, characterized by partially adhering the sand. (5) The method for producing sand for artificial lawns according to claim (4), wherein the resin constituting the aqueous resin emulsion contains a crosslinking agent or is a self-crosslinking resin. (6) Claim (4) wherein the amount of the aqueous resin emulsion applied is in the range of 0.5 to 5% by weight of the resin solid content based on the sand.
The method for producing sand for artificial lawns as described. (7) The amount of anti-blocking agent applied is 0.
The method for producing artificial lawn sand according to claim 4, wherein the content is in the range of 0.001 to 5% by weight. (8) An artificial lawn structure in which the grass grains are filled with sand, characterized in that the sand has a resin partially attached to the surface.