JP6076629B2 - Herbicidal material and herbicidal method using polymer chip - Google Patents

Description

The present invention relates to a herbicidal material obtained by previously mixing earth and sand and polymer chips, and a herbicidal method using the polymer chips.

Weeds grow naturally on the exposed ground and harm the beauty. In addition, weeds become a place for pests and cause insect damage. For these reasons, weeding is regularly performed by mowing, weeding, and herbicides. Mowing and weeding work are very hard work, and herbicides cause environmental pollution.

In order to solve such problems, the ground of walking paths, parks, gardens, etc. is paved with asphalt or cement, as in Patent Document 1, sheets and mats are laid on the soil, and gravel is spread. And was weeding. However, if it is paved with asphalt or cement, or if it is laid with gravel, it has no shock absorption, and if it falls, there is a risk of injury. When using a sheet or mat, there are problems such as meklet and floating, and the sheet shrinks over time, resulting in a gap between the sheets. An attempt to prevent the sheet from lifting with a fixing tool such as a fixing pin is not preferable because it causes a fall. Furthermore, there is a problem that the sheet breaks from the place where the fixture is applied, and the herbicidal effect is impaired.

On the other hand, Patent Document 2 discloses a technique for imparting cushioning properties to the ground by mixing a rubber chip having a high specific gravity with a racetrack or ground earth and sand. The rubber chip of Patent Document 2 makes it difficult to separate the rubber chip by adding barium sulfate to approximate the specific gravity of the rubber chip to that of earth and sand. Patent Document 2 does not describe the herbicidal effect, and it is also unclear how much rubber chips are mixed with earth and sand.

JP 2007-107353 A JP 2001-241008 A

An object of the present invention is to provide a herbicidal material and a herbicidal method that can be applied to soil very easily and that exhibit a herbicidal effect over a long period of time without being deteriorated or washed away by wind and rain. And

The present invention relates to a herbicidal material obtained by mixing earth and sand and 0.9 to 2.0 g / cm ³ of polymer chips having a bulk density equivalent to or higher than that of earth and sand, and the content of the polymer chips The above-mentioned problems are solved by a herbicidal material characterized in that the amount is 15 to 70% by weight, and a herbicidal method characterized by spraying the herbicidal material so that the ground surface is covered.

In the above-mentioned herbicidal method, the above-mentioned problem can be solved not by mixing the earth and sand with the polymer chips in advance but also by a method of pouring the polymer chips into the earth and sand in the applied soil with a cultivator. That is, 0.9 to 2.0 g / cm ³ of polymer chips having a bulk density equivalent to or higher than the earth and sand in the soil, so that the content of the polymer chips is 15 to 70% by weight. It is a weed control method characterized by being mixed with the soil in the soil by spraying onto the soil and swallowing it with a cultivator.

The polymer chip used for the herbicidal material of the present invention has a bulk density equivalent to or higher than that of earth and sand so that specific gravity separation does not occur over time. The polymer chip is composed of a polymer component and a filler, and the specific gravity is adjusted by adding a filler having a relatively high specific gravity to a polymer component having a relatively low specific gravity. Since the bulk density varies depending on the type of earth and sand, it is difficult to specify the bulk density of the polymer chip, but it is excellent in drainage and is a pure sand soil (bulk density of about 1.6) that is frequently used as athletic field soil and garden soil. and, since other sediment in the range of the bulk density is approximately ^{1.3~2.0g / cm 3, 1.2~3.0g / cm} 3 the true density of the polymer chips, preferably a true density 2. The bulk density of the earth and sand and the polymer chip is made equal by changing the particle diameter and the shape of the particle to 5 to 3.0 g / cm ³ . Equivalent here means that the bulk density of the polymer chip is in the range of 0.9 to 2.0 g / cm ^{3 with} respect to the bulk density of earth and sand of 1.3 to 2.0 g / cm ³ , more preferably, The range is 1.3 to 2.0 g / cm ³ . When the bulk density is less than 0.9 to 1.3 g / cm ³ , the bulk density is lower than that of general earth and sand. More preferably, the bulk specific gravity of the earth and sand and the polymer chip should coincide with each other in the range of 1.3 to 2.0 g / cm ³ .

The polymer chip preferably has an average particle size equivalent to the earth and sand to be mixed. Since the average particle size varies depending on the type of earth and sand, it is difficult to specify the average particle size of the polymer chip. It is preferable to adjust between -20 mm. By making the particle size equivalent to the earth and sand to be mixed, mixing becomes easy, and separation does not easily occur. Furthermore, the sense of incongruity disappears by aligning with the particle size of the earth and sand.

As the polymer component, a polymer compound that can be formed into a chip shape is used. Among the polymer compounds, one or a mixture of two or more selected from the group consisting of rubber, thermoplastic elastomer, and thermoplastic resin is easy to mold, and therefore it is preferable to use these. Of these, thermoplastic elastomers are particularly preferable because they have excellent cushioning properties and can be easily reused by remelting the polymer chip.

Since the polymer chip of the present invention is mixed with earth and sand, an antioxidant is not necessary in principle. However, an antioxidant may be added to protect the polymer chip near the ground surface from ultraviolet rays or the like. When the polymer chip is rubber, vulcanization containing sulfur or peroxide is added. When vulcanization is performed, a vulcanization accelerator and a vulcanization acceleration auxiliary for shortening the vulcanization time may be added.

The filler uses a material having a relatively higher specific gravity than the polymer chip. Among such substances, titanium oxide, zinc oxide, barium sulfate, magnesium oxide and magnesium hydroxide have a high density of 2.4 to 5.5 g / cm ^3, and no harmful components are produced even when buried in the soil. Preferably, one or a mixture of two or more selected from the group consisting of these compounds is used as the filler. By making the bulk density of the earth and sand and the polymer chip equal or higher with such a substance, it is possible to prevent the earth and sand and the polymer chip from being separated or the polymer chip from being washed away by rainwater or the like. Magnesium oxide reacts with water to form magnesium hydroxide, which is particularly preferable because it has a particularly high effect of enhancing hydrophilicity and preventing polymer chips from being washed away by rainwater. Therefore, the main component of the filler is preferably magnesium oxide.

The polymer chip may be mixed with earth and sand in advance so as to have a content rate of 15 to 70% by weight as a herbicidal material and sprayed on the ground surface. It may be spread over the ground surface so that the content is 15 to 70% by weight, and mixed with the earth and sand of the soil. In the latter case, when the earth and sand and polymer chips are mixed with a cultivator, the earth and sand and polymer chips can be mixed easily and reliably. If a cultivator is used, the embedding depth of a polymer chip can be easily adjusted by changing the depth of a rotary blade (rotary). The embedding depth of the polymer chip is preferably 1 cm or more, more preferably 3 cm or more. This is because if the embedding depth is smaller than this, the herbicidal effect is not sufficient. From the viewpoint of the herbicidal effect, there is no particular upper limit of the embedding depth. However, if the embedding depth is excessively increased, the cost is increased. Similarly, in the case of a herbicidal material obtained by previously mixing polymer chips and earth and sand, it is preferable to spray the herbicidal material so as to have a thickness of 1 to 12 cm, more preferably 3 to 12 cm from the ground surface.

The polymer chip of the present invention may be colored by adding a pigment or the like. By coloring in green or red, etc., the land can be partitioned for each purpose, used as a landmark, and the laying location can be given design.

In the herbicidal method of the present invention, a plurality of layers having different mixing ratios of earth and sand and polymer chips are provided, and the mixing ratio of the polymer chips in the upper layer is set higher than the mixing ratio of the lower polymer chips. Good. Thereby, compared with the case of a single layer, it becomes possible to obtain an equivalent herbicidal effect with a smaller amount of addition of polymer. As a result, it is possible to reduce the cost because the amount of polymer chips to be mixed is small. As described above, when the bulk density is less than 0.9 to 1.3 g / cm ³ , the specific gravity separation naturally proceeds. Therefore, in this range, the mixing ratio of the polymer chip in the upper layer is set to be higher than the mixing ratio of the lower layer polymer chip. Can be higher. Moreover, within this bulk density range, the polymer chip and the earth and sand are not completely separated, the mixing ratio of the polymer chip and the earth and sand is high near the surface layer, and the mixing ratio is low in the ground. Therefore, the polymer chip is not easily washed away by wind and rain, and is not easily affected by ultraviolet rays.

The herbicidal material of the present invention is difficult to separate from earth and sand and can maintain the herbicidal effect over a long period of time. That is, since the state in which the polymer chip and earth and sand are mixed can be maintained, the polymer chip does not float on the ground surface. Therefore, the polymer chip is not washed away by rainwater, and the polymer chip is not deteriorated by direct sunlight.

It is the figure which showed typically the confirmation test method of the herbicidal effect of an Example. It is the graph which showed the change of the herbicidal effect when changing the content rate of the polymer chip in the mixture of earth and sand and the polymer chip.

Embodiments of the present invention will be described below.

The herbicidal material of the present invention is a mixture of earth and sand and polymer chips having a bulk density equivalent to or higher than that of earth and sand. The polymer chip is composed of a polymer component and a filler that makes the density equal to or higher than that of earth and sand.

In the case where the earth and sand and the polymer chips are mixed in advance, as the earth and sand to be mixed, any earth and sand such as sand, gravel, clay, agglomerated earth (humus earth) or a mixture thereof can be used. Among these, a true sandy soil made by weathering granite, particularly one having a small amount of clay is excellent in drainage, and it is preferable that separation between the polymer chip and the soil is difficult to occur.

As the polymer component, it is preferable to use any one of rubber, thermoplastic elastomer, thermoplastic resin, or a mixture of two or more thereof.

As the rubber, it is preferable to use a vulcanizable rubber. This is because vulcanization improves its elasticity and strength. As vulcanizable rubber, natural rubber (NR), epoxidized natural rubber (ENR), isoprene rubber (IR), styrene butadiene rubber (SBR), butadiene rubber (BR), chloroprene rubber (CR), nitrile rubber ( NBR), butyl rubber (IIR), acrylic rubber (ACM), ethylene propylene copolymer (EPM), ethylene propylene diene copolymer (EPDM), and chlorosulphonated polyethylene (CSM). At least any one of these may be adopted, or any plurality of types may be combined.

Examples of the thermoplastic elastomer include styrene (TPS), olefin (TPO), polyvinyl chloride (TPVC), polyester (TPEE), polyurethane (TPU) and amide (TPA) thermoplastic elastomers. .

Examples of the thermoplastic resin include general-purpose resins such as polyethylene, polypropylene, polystyrene, acrylic resin, polyvinyl chloride, polyester, and polyamide.

As the vulcanizing agent for vulcanizing the rubber, sulfur, peroxide, or the like can be used, and only one of these may be adopted, or a plurality of arbitrary types may be combined.

Vulcanization accelerators include guanidine, aldehyde ammonia, aldehyde amine, thiazole, sulfenamide, thiuram, dithiocarbamate, xanthate, and fatty acids such as stearic acid as vulcanization accelerators. Metal oxides such as zinc oxide can be used, and only one of these may be adopted, or any plurality of types may be combined.

As the anti-aging agent, amine-based, phenol-based, wax, and the like can be used, and only one of these may be adopted, or a plurality of arbitrary types may be combined.

When rubber is used as the polymer component, for example, a polymer chip is produced in the following manner. A vulcanizing agent is obtained by adding a vulcanizing agent and a filler to the rubber and kneading it using a Banbury mixer, kneader, roll, or the like, then forming a shape that is easy to grind and heating. The molded product of the vulcanized rubber is pulverized with a rotary pulverizer and sieved using a mesh or the like to obtain a polymer chip having an arbitrary particle size.

When a thermoplastic elastomer or a thermoplastic resin is used as the polymer component, for example, a polymer chip is produced in the following manner. A thermoplastic elastomer or thermoplastic resin and a filler are put into an extruder and extruded into a shape that is easy to grind. Thereafter, the compact is pulverized with a rotary pulverizer and sieved using a mesh or the like to obtain a polymer chip having an arbitrary particle size.

After spraying the above polymer chips directly on the laying site, mix with the soil directly with a tiller (including tractor) or mix the polymer chips in advance so that the polymer chip content is 15 to 70% by weight In this case, weed protection can be achieved by spreading the laying part.

Next, based on an Example, this invention is demonstrated more concretely.

Polymer chips according to Experimental Examples 1 to 5 were prepared by blending the polymer component and the filler in the ratio shown in Table 1.

Experimental Example 1 is a rubber chip using rubber (natural rubber) as a polymer component. The rubber chip was manufactured as follows. A natural rubber shown in Table 1, each filler, a vulcanizing agent, a vulcanization accelerator, an anti-aging agent, and a pigment were put into a Banbury mixer, kneaded, and molded into a sheet by a molding apparatus. This was put in a vulcanizing furnace and vulcanized at 120 ° C. for 60 minutes. This was pulverized with a rotary pulverizer and sieved to obtain rubber chips having an average particle size of 3 mm. When the bulk density of the rubber chip was measured by the test method of JIS K7365, it was 1.7 g / cm ³ . Sulfur is used as the vulcanizing agent, 2-mercaptobenzothiazole is used as the vulcanization accelerator, stearic acid is used as the vulcanization accelerating aid, and 2-6 ditertiarybutyl- 4-methylphenol was used, and phthalocyanine green was used as a pigment.

In Experimental Example 2, a thermoplastic elastomer (SEPS) is used as a polymer component to form an elastomer chip. The production of the elastomer chip was performed as follows. Each of the fillers shown in Table 1, the anti-aging agent, and the pigment shown in Table 1 were put into an extruder for resin molding and extruded from a die while being heated at 230 ° C. to form a sheet. This was pulverized by a rotary pulverizer and sieved to obtain an elastomer chip having an average particle diameter of 3 mm. When the bulk density of the elastomer chip was measured by the test method of JIS K7365, it was 1.5 g / cm ³ . 2-6 ditertiarybutyl-4-methylphenol was used as an anti-aging agent, and phthalocyanine green was used as a pigment.

In Experimental Example 3, a thermoplastic resin (PP) is used as a polymer component to form a plastic chip. The plastic chip was manufactured as follows. Each of the fillers shown in Table 1, the anti-aging agent, and the pigment shown in Table 1 was put into an extruder for resin molding and extruded from a die while being heated at 210 ° C. to be molded into a sheet. This was pulverized by a rotary pulverizer and sieved to obtain a plastic chip having an average particle diameter of 3 mm. When the bulk density of the plastic chip was measured by the test method of JIS K7365, it was 1.5 g / cm ³ . 2-6 ditertiarybutyl-4-methylphenol was used as an anti-aging agent, and phthalocyanine green was used as a pigment.

Experimental Example 4 is a rubber chip manufactured by the same composition and manufacturing method as Experimental Example 1 except that the amount of magnesium oxide was increased in the rubber chip of Experimental Example 1 instead of barium sulfate. When the bulk density of the rubber chip was measured by the test method of JIS K7365, it was 1.5 g / cm ³ .

Experimental Example 5 is a comparative example prepared for the target experiment, and is a general-purpose rubber chip to which no filler for adjusting the specific gravity is added. 60 parts by weight of pigment and carbon black as a reinforcing material are added. Sulfur as vulcanizing agent, 2-mercaptobenzothiazole as vulcanization accelerator, zinc oxide and stearic acid as vulcanization accelerating aid, and N-1,3dimethylbutyl-N′-phenyl-P— as anti-aging agent Naphthenic process oil was used as the softening agent for phenylenediamine. When the bulk density of the rubber chip was measured by the test method of JIS K7365, it was 0.8 g / cm ³ .

[Example 1]
A pure sand soil for gardening (bulk density: 1.5 g / cm ³ ) was prepared, and rubber chips of Experimental Example 1 were mixed with the true sand soil at a ratio of 5 to 100% to obtain a herbicidal material.

The herbicidal effect of the above herbicidal materials was examined as follows. First, as shown in the schematic diagram of FIG. 1, the field was partitioned into 50 cm × 50 cm, and the same amount of Arabidopsis seeds 2 was sown in each partition 1. Arabidopsis thaliana was cultivated by sowing each herbicide with a herbicide whose content of polymer chips was changed at a rate of 5 to 100%. The herbicidal material was spread to the extent that a 5 cm thick layer of herbicidal material was formed on the ground surface. At the time when 3 months passed, the plant was cut and the raw weight of Arabidopsis was measured for each section. The measurement results are shown in the graph of FIG. The experiment was conducted independently on the herbicidal material using the polymer chips of Experimental Examples 1 to 4. For comparison, Experiment 5 was also performed under the same conditions as in Experiment 1. The measurement results are shown in the graph of FIG.

As apparent from the graph of FIG. 2, the herbicidal effect of Arabidopsis thaliana increased when the rubber chip content was about 15% by weight, and the herbicidal effect reached saturation at 70% by weight. Although illustration is omitted in view of the ease of viewing the graph, similar inflection points were observed in the elastomer chip of Experimental Example 2, the plastic chip of Experimental Example 3, and the rubber chip of Experimental Example 4. From this result, it was found that the polymer chip is preferably blended in an amount of 15 to 70% by weight, more preferably 30 to 70% by weight based on earth and sand. Although 70% by weight or more of the polymer chip may be blended, the herbicidal effect is saturated and the herbicidal effect corresponding to the cost required for laying the rubber chip cannot be obtained.

In Experimental Example 5 to be compared, rubber chips appeared on the ground surface during exposure to rain, and were washed away or lost by blowing in the wind, so that a sufficient herbicidal effect was not obtained (FIG. 2). .

[Example 2]
Next, it was confirmed whether or not the herbicidal effect could be obtained by a method in which the polymer chips of Experimental Examples 1 to 5 were directly sprayed on the soil and were swallowed with a cultivator. First, it was 1.3 g / cm < ³ > when the bulk density of the soil of the vacant lot to test was confirmed. Next, the weeds that had grown in the vacant land were drawn out and partitioned into 50 × 50 cm in order to spray the polymer chips of Experimental Examples 1-5. The weeds in each plot were removed, but the soil was not replaced so that weed seeds remained. Next, 24.375 kg of polymer chips of Experimental Examples 1 to 5 were sprayed to each compartment so that the content of the polymer chips was 60% by weight. In this example, the penetration depth of the cultivator is set to 5 cm, and since one section is 50 × 50 cm, the capacity of the soil is about 16.25 kg. Polymer chips sown in each compartment were squeezed into each compartment with a cultivator.

After 7 months, the state of the vacant lots that were partitioned was confirmed visually to check the weed growth. In any section where the polymer chips of Experimental Examples 1 to 4 were seeded, almost no weeds were grown, and it was confirmed that the herbicidal effect of the present invention was exhibited even by plowing with a cultivator. In particular, in Experimental Example 4 using magnesium oxide as a filler, the polymer chip rarely floated on the ground surface due to rainwater, and the herbicidal effect was excellent. On the other hand, in Experimental Example 5, weeds were thickened and the herbicidal effect was not exhibited. Examination of the soil revealed that most of the rubber chips were washed away by wind and rain.

Since the herbicidal material of the present invention is mixed with earth and sand, it is not exposed to direct sunlight. Therefore, the problem of deterioration due to ultraviolet rays does not occur unlike conventionally known rubber sheets and mulching materials. When the state of the polymer chip of Experimental Examples 1 to 4 in Example 2 was actually confirmed, the elasticity was maintained in Experimental Examples 1, 2, and 4. In Experimental Example 3, the soundness of the resin was maintained. On the other hand, when the rubber chip of Experimental Example 5 that remained slightly on the soil surface was confirmed, it was deteriorated by ultraviolet rays.

The herbicidal material obtained by previously mixing soil and polymer chips shown in Example 1 is easy because it only spreads on the soil to be weeded, and is optimal for general consumers such as home centers. The herbicidal method for polymer chips shown in Example 2 is optimal for business use because the weight per unit volume is small and the transportation cost of the polymer chips can be suppressed.

[Example 3]
In the same manner as in Example 1, rubber (natural rubber) was used as a polymer component to obtain a vulcanized rubber sheet having the composition shown in Table 2. This was pulverized and sieved to obtain a rubber chip according to the present invention having an average particle diameter of 3 mm (Experimental Example 6). When the bulk density of the rubber chip was measured by the test method of JIS K7365, it was 1.1 g / cm ³ .

The herbicidal material was mixed with horticultural pure sand soil (bulk density 1.5 g / cm ³ ) so that the rubber chip content was 50% by weight. The herbicidal material was sown in a vacant land from which weeds were removed in the same manner as in Example 2 to confirm the herbicidal effect. The herbicidal material was spread to the extent that a 2 cm thick layer was formed on the ground surface.

Since the rubber chip of Experimental Example 6 has a lower bulk density than that of true sand, the rubber chip moved to the vicinity of the ground surface as time passed. However, the content of the rubber chips was maintained at about 70% by weight near the surface of the earth, and the rubber chips and the true sand soil were not completely separated, and the herbicidal effect was exhibited. Since the content of rubber chips increases near the ground surface, as a result, a sufficient herbicidal effect was obtained with a small amount of rubber chips mixed. When the state of the rubber chip was confirmed, the elasticity was maintained and there was no appearance of deterioration due to ultraviolet rays.

1 section 2 seed

Claims (4)

A herbicidal material obtained by mixing earth and sand and polymer chips not containing a herbicide of 0.9 to 2.0 g / cm ³ having a bulk density equivalent to or higher than that of earth and sand, and containing polymer chips A herbicidal material having a rate of 15 to 70% by weight. The polymer chip is a polymer component comprising one or a mixture of two or more selected from the group consisting of rubber, thermoplastic elastomer, and thermoplastic resin,
The herbicidal material according to claim 1, comprising a filler comprising one or a mixture of two or more selected from the group consisting of titanium oxide, zinc oxide, barium sulfate, magnesium oxide and magnesium hydroxide. A herbicidal material obtained by mixing earth and sand and polymer chips not containing a herbicide of 0.9 to 2.0 g / cm ³ having a bulk density equivalent to or higher than that of earth and sand, and containing polymer chips A herbicide with a rate of 15-70% by weight,
A herbicidal method using a polymer chip, which is sprayed so that the ground surface is covered. A polymer chip not containing a herbicide of 0.9 to 2.0 g / cm ³ , which has a bulk density equivalent to or higher than that of soil in the soil, so that the content of the polymer chip is 15 to 70% by weight. A weed control method using polymer chips, characterized in that it is sprayed on the ground surface and mixed with soil in the soil by swallowing with a cultivator.

Images