JP3481414B2 - Permeable cloth sheet - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water-permeable cloth sheet, and more specifically, it is generally used by being laid on the surface of soil and has excellent light-shielding property and water-permeable property. Regarding the seat.

[0002]

2. Description of the Related Art Conventionally, a woven fabric in which a flat yarn made of a synthetic resin such as a polyolefin is struck at a high density is laid on a soft ground, and the soft ground is improved by spreading it on top of it and filling it with earth and sand. It may be used for civil engineering work such as temporary road construction and residential land development. This material is
Since it is a woven fabric, there are gaps in the weave structure, and since pressure of earth and sand is also generated, it has drainage properties and is useful as a ground that can be stabilized. However, since it is a dense woven fabric, when it is used without earth pressure, for example, by simply laying it on the soil surface, the fabric material is made of synthetic resin and has water repellency. Occurs, and the water does not effectively permeate, and the water remains in the form of beads on the surface of the fabric. In other words, due to insufficient water permeability, laying on the ground to prevent muddyness may result in a pool of water.

Next, there is an attempt to use the above-mentioned woven fabric to prevent weeds from growing in orchards, vegetable gardens, etc., and to prevent weeds from growing in order to maintain a beautiful appearance around buildings and street trees.
Here, as a means for preventing the growth of weeds, a means such as a film that completely blocks light and water is conceivable, but a film that completely blocks water should be used in the soil when used as the root of a plant. Since rainwater does not enter, the soil will dry and even the expected plants will die, and there will be problems such as pooling due to the inability to drain the rainwater.The film also has low tensile strength and piercing strength, and it will spread. There is a problem such as damage when it cannot withstand the tensile strength applied at the time of trampling or trampling, and the problem that it is torn without being able to withstand the vigor of plants with strong vigor such as grass and grass There is. Therefore, in some cases, instead of the film, a woven or knitted fabric or a non-woven fabric made of a polyolefin fiber is used to prevent weeds from growing.

However, polyolefin fibers have tensile strength and puncture strength, but are hydrophobic, and when the voids of the woven or knitted fabric or the nonwoven fabric are small, water may not be able to permeate due to surface tension and may stay on the surface. However, if an attempt is made to solve this problem by increasing the size of the voids, the light-shielding property is deteriorated, and the transmitted light from the voids may promote the growth of weeds, making it impossible to achieve the purpose of the grass-controlling sheet. In other words, the problem is to impart water permeability even when used for the purpose of weed control. In terms of imparting water permeability, for example, a thread or string made of natural fibers such as cotton, silk, wool, or a water-permeable thread or string utilizing the capillary phenomenon such as multifilament yarn or staple filament yarn of synthetic fiber is used. Although a grass-proof sheet (Japanese Utility Model Publication No. Sho 60-33141) made of a flat yarn knitted woven fabric made of mixed fibers is also disclosed, there are many problems such as a complicated manufacturing process and poor productivity and high cost. , Further improvement was requested.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems technically, the present invention is a method that is easy to handle, economical and inexpensive, has sufficient light-shielding property and water permeability, and is strong. An object of the present invention is to provide a water-permeable cloth sheet which is excellent and can be used for various purposes such as prevention of weed overgrowth in agriculture and horticulture, prevention of dirt due to mud splashes in flowerpots, and prevention of mud including general household use.

[0006]

According to the present invention, a coating layer containing a polyoxyalkylene fatty acid ester compound is formed on the surface of a woven or knitted fabric obtained by finely woven and knitting a polyolefin flat yarn as warp and weft yarns. It is a water-permeable cloth sheet. In addition, as another mode, a coating layer containing a polyoxyalkylene fatty acid ester compound is formed on the surface of a polyolefin-based flat yarn, which is a woven or knitted fabric in which the polyolefin-based flat yarn is densely woven and knitted. Is a water-permeable cloth sheet.

In the present invention, a coating layer containing a specific surfactant is formed on the surface of a sheet body made of a woven or knitted fabric using a polyolefin-based flat yarn, or a specific surfactant is contained on the surface in advance. By forming a woven or knitted fabric from a polyolefin-based flat yarn having a coating layer formed thereon, the sheet body is rendered hydrophilic, and a water-permeable cloth sheet having water permeability while maintaining sufficient light-shielding properties is obtained. Is.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, the flat yarn used for constructing the water-permeable cloth sheet is prepared by introducing a polyolefin resin into an extruder and forming a film by a T-die flat method or an inflation method. ~ 2
It is a high-strength flat yarn formed by slitting to a width of 0 mm, heat drawing, and then heat relaxation treatment. Here, the heat stretching of the film is usually in the temperature range of 120 to 150 ° C. and is 5 to 20 from the melting point of the polyolefin resin used.
It is carried out at a temperature as low as about 0 ° C., and the draw ratio is preferably 3 to 15 times, more preferably 5 to 10 times. That is, if the draw ratio is less than 3 times, sufficient strength as a sheet base material cannot be obtained, and if it exceeds 15 times, the orientation in the drawing direction is too strong and the flat yarn may crack, and stable productivity is obtained. Tends to be a problem.

The flat yarn has a single yarn fineness of 3
It is from 00 to 2000 denier (hereinafter abbreviated as d), preferably from 500 to 1500 d. If the single yarn fineness is less than 300 d, the tensile strength becomes insufficient, which causes problems such as damage when the cross sheet is stretched, and if it exceeds 2000 d, the cross sheet lacks flexibility and cannot adhere to the laid surface having irregularities.

Carbon black may be added to the flat yarn for the purpose of improving the light-shielding property and the weather resistance. The content of carbon black in the polyolefin resin is 0.1 to 3% by weight, preferably 0.5 to 1% by weight. Also, like any carbon black, other inorganic fillers, antioxidants, ultraviolet absorbers, light stabilizers,
You may mix | blend normally used additives, such as a lubricant, a pigment, a flame retardant, a foaming agent, and a nucleating agent.

The flat yarn is densely woven as warp and weft to form a woven or knitted fabric, which is used as a base material.
The weaving / knitting structure here is not particularly limited, and may be plain weave, twill weave, warp knitting fabric, or the like as long as it is a woven fabric, and may be any of flat knitted fabric or warp knitted fabric as long as it is a knitting fabric. In order to develop, it is preferable that the number of voids in the tissue is reduced and the misalignment is unlikely to occur. Specifically, it is preferable that the driving density of the flat yarn is about 10 to 35 yarns / inch for both warp and weft yarns depending on the single yarn fineness, and the porosity of the woven or knitted fabric is 5% or less.
That is, when the porosity of the woven or knitted fabric exceeds 5%, the light-shielding property cannot be maintained, and the function of preventing overgrowth of weeds becomes insufficient.

The basis weight of this woven or knitted fabric is 50 to 500.
preferably ^{g / m 2, 100~400g / m} 2 is more preferable. That is, when the basis weight is less than 50 g / m ^2, it is easily scattered by wind even when it is laid, and the basis weight is 500
If it exceeds g / m ² , it becomes too heavy and difficult to handle.

Further, as the mechanical strength of this woven or knitted fabric,
Tensile strength is 100kgf / 5cm or more, tear strength is 20
It is preferably not less than kgf. In other words, if the tensile strength is less than 100 kgf / 5 cm, there will be problems such as damage due to insufficient strength during extension of the laying work, and even when laid as an underlay of concrete, cracks will occur due to long-term ground subsidence, etc. When the tear strength is less than 20 kgf, there is also a problem that the plant is pierced and torn without being able to withstand the growth of plants with strong growth such as Pondaceae.

Next, a coating layer containing a polyoxyalkylene fatty acid ester compound is formed on the surface of the woven or knitted fabric for the purpose of improving water permeability. Alternatively, it is also possible to form a coating layer containing a polyoxyalkylene fatty acid ester compound on the surface of the flat yarn in advance, and use this for at least one of the warp and weft yarns to finely woven and knit it. Here, the polyoxyalkylene fatty acid ester-based compound used is an ester-based compound derived from polyethylene glycol and a saturated or unsaturated higher aliphatic carboxylic acid, and belongs to a nonionic surfactant. Examples thereof include polyoxyethylene oleate and polyoxyethylene stearate.

The polyoxyalkylene fatty acid ester compound has an HLB value of 8 to 1 determined by the following mathematical formula.
It is preferably 4.

[0016]

[Equation 1]

When the HLB value is within the above range, the molecular weight of polyethylene glycol is appropriately adjusted, and the polyethylene glycol has excellent affinity for resins and hydrophilicity.

As a method for forming the coating layer containing the polyoxyalkylene fatty acid ester compound, a solution or emulsion containing the polyoxyalkylene fatty acid ester compound is dipped or coated on the surface of the woven or knitted fabric or the flat yarn. A known method such as a method, a brushing method, or a spray method can be adopted.

Here, the coating layer containing the polyoxyalkylene fatty acid ester-based compound has a solid content conversion amount of preferably 0.1 to 20 g / m ² , more preferably 1 to 10 g / m ² . . That is, when the solid content-adhered amount is less than 0.1 g / m ² , the water permeability is insufficient and 20 g / m ²
Even if it exceeds m ² , the effect is not changed and it is not economical.

The water-permeable cloth sheet of the present invention having such a structure is laid on soil or aisle in agriculture or horticulture to prevent weeds, and in general households to be laid on the ground in the garden to prevent mud, or pots. In cultivation, it is used for multiple purposes, such as laying on soil or a bench and placing a flowerpot on it to prevent spattering due to rain.

[0021]

【Example】

Test method 1. Tensile test: JIS-L1096 compliant 2. Tear test: JIS-L1096 compliant 3. Light-shielding test: Photocell illuminance meter TOPCON, IM-3
Using a mold, the illuminance meter was set to 10000 Lux when there was no sample, and then the sample was set to measure the light-shielding rate (Japan Chemical Fiber Inspection Association method). 4. Water permeability test: 200 cc of water was sprayed on the sample, and the surface condition was visually observed.

Example 1 High-density polyethylene (density = 0.958 g / cm ³ , MFR = 5 g / 10 min.) As a polyolefin resin
Select 0.5% by weight of high-density polyethylene 99.5% by weight of carbon black and put into an extruder to form a black film by the inflation method. After slitting this film, contact with a hot plate. Stretching temperature of 120 ° C., annealing temperature of 124
Heat drawing was performed at a temperature of 5 ° C. and a draw ratio of 5 to obtain a flat yarn having a fineness of 950 d. Using this flat yarn as warp and weft, a plain weave fabric was formed with a driving density of 15 warps / inch. Next, an aqueous emulsion containing 1% by weight of polyoxyethylene oleic acid ester having an HLB value of 9 was prepared, and the woven fabric previously formed was dipped in the aqueous emulsion to form a uniform film, which was then dried at room temperature to 1 After drying for an hour, heat treatment was performed at 120 ° C. for 2 minutes to form a coating layer, and the cross sheet of Example 1 was obtained. The coating amount here was set to 5 g / m ² as a solid content conversion amount.

The cross sheet of Example 1 has a basis weight of 20.
0 g / m ² , tensile strength 138 kgf / 5 cm, tear strength 33.4 kgf, light-shielding rate 97.6% (set porosity 0.24
%)Met. Further, in the water permeability test, it was able to quickly permeate water.

[0024] When this embodiment was used by actually covering the root soil of a roadside tree for the purpose of preventing weed reproduction,
Rainwater did not stay on the cloth sheet, and even when water was applied from above the cloth sheet, the water penetrated the cloth sheet and was quickly absorbed by the soil. In addition, there was no damage due to insufficient strength during spreading, the effect of preventing weed overgrowth was remarkable for one year, and there were no accidents such as tears and damage due to the growth of plants with strong growth potential such as Japanese pampas grass.

Example 2 The flat yarn used in Example 1 was dipped in an aqueous emulsion containing 1% by weight of polyoxyethylene oleic acid ester having an HLB value = 9, and this was used as a warp and weft yarn. A woven fabric was prepared in the same manner as in Example 1. This woven fabric was dried at room temperature for 1 hour and then heat-treated at 120 ° C. for 2 minutes to obtain a cross sheet of Example 2. Similarly, in the water permeability test of the cloth sheet of Example 2, water was quickly permeated.

COMPARATIVE EXAMPLE A water permeability test was conducted by using as a comparative example the same procedure as in Example 1 except that the coating layer containing polyoxyethylene oleic acid ester was not formed. It was in the form of beads and stayed on the surface of the woven fabric.

[0027]

As described above, according to the present invention, since the woven and knitted fabric composed of the flat yarn made of the polyolefin resin serves as the base material, it has a high density and high strength and is easy to handle and durable. In addition, the yarn structure of the woven or knitted fabric has unevenness on the surface to provide slip resistance. Further, since the woven or knitted fabric has a coating layer containing a polyoxyalkylene fatty acid ester-based compound, it can be laid in soil and has good water permeability without passing mud, and can prevent mud. Further, it is densely woven and has water permeability while maintaining a sufficient light-shielding property, so that the reproduction of weeds can be effectively prevented. Therefore, the water-permeable cloth sheet of the present invention is effective in that it can be used for various purposes in the fields of agriculture, civil engineering and construction, and even general households.

[Brief description of drawings]

FIG. 1 is a partially enlarged plan view of a water-permeable cloth sheet of the present invention.

[Explanation of symbols]

1 cross sheet 2 flat yarn

Claims (2)

(57) [Claims] 1. A water-permeable cloth, wherein a coating layer containing a polyoxyalkylene fatty acid ester-based compound is formed on the surface of a woven or knitted fabric formed by densely weaving a polyolefin-based flat yarn as warp and weft yarns. Sheet. 2. A woven or knitted fabric in which a coating layer containing a polyoxyalkylene fatty acid ester compound is formed on the surface of a polyolefin-based flat yarn, and the polyolefin-based flat yarn is densely woven and knitted. A water-permeable cloth sheet.