JP3757331B2 - Grass protection sheet - Google Patents

Description

【００７０】
＜防草性試験方法＞
実施例、比較例の各防草シートを屋外に敷設して防草性の評価を行った。敷設条件は、４月〜翌１０月までの１８ヶ月間、場所は、千葉県内とした。
【００７１】
その結果、実施例、比較例ともに防草シートを敷設した部分には、草が生えず（評価◎）良好な防草性が得られることが確認できた。
【００７２】
＜耐久性（耐光性）試験方法＞
強エネルギー・サンシャイン・フェードメーター（スガ試験機株式会社製、ＳＥＬ−１型）を用いて１００ｈ、３００ｈ、４００ｈ光を照射した後、引張強さを測定し、引張強さ保持率を測定した。
【００７３】
引張強さ保持率(%)＝光照射後の引張強さ(N)/光照射前の引張強さ(N)
結果を図５に示す。
【００７４】
図５より、比較例の防草シートに対し、実施例の防草シートは、引張強さ保持率が５倍以上であり、耐光性が良好であることがわかる。
【００７５】
なお、実施例の防草シートにおいては、光照射前の引張強さ（縦：５８４Ｎ／５ｃｍ、横：３１９Ｎ／５ｃｍ）、伸び率（縦：８３．５％、横：８６．０％）、引裂強さ（縦：３７．３Ｎ、横：３９．２Ｎ）と、いずれの数値も防草シートとして好適であることを確認している。
【００７６】
＜防滑性試験方法＞
図６に示す防滑性試験装置を用いて、下記手順により測定を行った。
【００７７】
（１）１６ｃｍ×９ｃｍの試験片をヨコのみ３点とる。
【００７８】
（２）試験片５０を台紙上に塗膜面を上にして、両面テープにて固定する（しわのないように注意する）。
【００７９】
（３）台紙を測定板５２に両面テープにて固定する。
【００８０】
（４）測定板５２を水平にし、試験片５０の中央に静かに５０ｇ分銅５４をのせる（水平は分度器５６の目盛りにて確認する）。
【００８１】
（５）測定板５２をゆっくりと下方へ動かし、分銅５４の動き出す角度を読み取る（分度器５６の目盛りを読み取る）。
【００８２】
その結果、比較例の防草シートは、約２０°の傾斜時点で分銅が滑り始めた（評価×）のに対し、実施例の防草シートは約３０°の傾斜（評価◎）まで分銅が滑り出さなかった。よって、比較例の防草シートに比して、本発明の防草シートは防滑性が非常に良好であることがわかる。
【００８３】
＜透水性試験方法＞
JIS A 1208に準じて透水係数の測定を行った。なお、測定水温は１５℃とした。
【００８４】
その結果、比較例の防草シートの透水係数が１．１×１０^-2cm/secであった（評価◎）のに対し、実施例の防草シートは透水係数が３．３×１０^-4cm/cec（評価○）と、透水性にやや劣るが、防草シートとして十分な評価値であることがわかる。
【００８５】
＜通気性試験方法＞
実施例、比較例の防草シートを口に当て、それぞれ口で息を強く吹きつけて、裏面に空気が通るかどうかを判定した。その結果、比較例の防草シートが無理なく空気を通す（評価◎）のに対し、実施例の防草シートは通気性にやや劣る（評価○）が、防草シートとして十分な評価値であることがわかる。
【００８６】
＜難燃性試験方法＞
JIS L 1091 繊維製品の燃焼試験方法（Ｂ法）に準じて判定を行った。エアーミックスバーナーを用いて燃焼試験を行った結果、比較例の防草シートは、残炎時間０sec、燃焼長さ（炭化長）３．３ｃｍ（評価△）に対し、実施例の防草シートは、残炎時間０sec、燃焼長さ（炭化長）２．７ｃｍ（評価◎）と、非常に難燃性が良好であることがわかる。
【図面の簡単な説明】
【図１】本発明の防草シートを示す断面モデル図である。
【図２】本発明の防草シートの基材となる不織布を製造する工程概略図である。
【図３】不織布の圧接接着に使用する圧接ローラの概略図である。
【図４】基材（不織布）に表面塗膜剤を塗布する工程の工程概略図である。
【図５】実施例における耐光性試験結果を示すグラフ図である。
【図６】防滑性試験に使用する装置の概略図である。
【符号の説明】
１２：エクストルーダー
１３：無機系粒子及び／又は有機系粒子
１５：バインダー
１８：紡糸口金
２０：フィラメント
２４：ベルトコンベア
２８：ウェブ
２９：圧接機
３０：圧接ロール
３４：不織布
３６：ナイフコーター機
４２：防草シート
４４：ヒートセット機[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a herbicidal sheet. More specifically, the present invention relates to a herbicidal sheet based on a non-woven fabric made of long fibers that has an excellent effect of suppressing the growth of weeds and can be suitably used in the agricultural field, the civil engineering field in a broad sense, and the like.
[0002]
[Prior art]
Conventionally, several means have been put to practical use as the weedproof means. Herbicides are commonly used as chemical herbicides, but problems such as temporary effects, damage to surrounding crops, and pollution when discharged into water. Had a point.
[0003]
Therefore, a means for laying a weedproof sheet made of non-woven fabric to carry out the weed prevention has been put into practical use and attracting attention (see Japanese Patent Publication No. 4-52727). However, the durability is inferior (the lifetime is limited to about 3 years), and when laid on an inclined surface, there are problems such as slipperiness when a person walks. In addition, there are cases where perforation occurs due to throwing away cigarette butts, and no satisfactory one has appeared.
[0004]
[Problems to be solved by the invention]
In view of the above, the present invention provides a herbicidal material that has excellent herbicidal properties, has air permeability and water permeability, and has a non-slip property that prevents the surface from slipping. It is an object to provide a sheet.
[0005]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present inventors have come up with a herbicidal sheet having the following constitution in the course of diligent research and development.
[0006]
In the herbicidal sheet based on a nonwoven fabric formed by pressure-bonding long fibers, on the surface of the nonwoven fabric, The particle size is 10 to 500 μm A coating film layer made of a matrix material having inorganic particles and / or organic particles as a dispersed phase and a binder (resin binder) as a continuous phase is formed.
[0007]
By using a non-woven fabric formed by press-bonding long fibers, it has a high light-shielding effect, and also exerts a strong herbicidal effect that can prevent breakthroughs even for plants such as rice that have a strong vitality. can do. In addition, by using a non-woven fabric as a base material and forming a coating layer with inorganic particles and / or organic particles as a dispersed phase and a binder continuous phase on the surface of the non-woven fabric, the seeds flying on the surface are fixed. In fact, it does not impede the growth of surrounding trees and plants because it has water permeability and air permeability.
[0008]
Moreover, there is no accumulation of water due to rain or the like, and even if the ground becomes soft, no soil or water is ejected to the surface. Moreover, it is excellent in durability (year in which it can be used). Furthermore, when walking on a grass-proof sheet installed on an inclined bank, the surface is hard to slip, so it does not fall down and is safe.
[0009]
In the above configuration, it is desirable that the weedproof sheet is subjected to a flame retardant treatment. By applying a flame retardant treatment, even if the cigarette butt is thrown away, it can be prevented from burning and causing perforation.
[0010]
As the flame retardant treatment, a method of applying a flame retardant to the matrix material is easy and desirable.
[0011]
Furthermore, when a recycled material is used as the inorganic particles and / or organic particles, an environmentally-friendly weedproof sheet can be obtained, which is economical.
[0012]
In producing the herbicidal sheet, the surface coating agent of the present invention which is a matrix material having inorganic particles and / or organic particles as a dispersed phase and binder as a continuous phase can be used. And it is desirable for the said surface coating agent to contain a flame retardant.
[0013]
And, the above-mentioned herbicidal sheet directly forms an aggregate of continuous filaments from a heat-melted synthetic resin, and after forming a non-woven fabric by a spunbond method in which pressure welding is performed using a pressure roll, on the surface of the non-woven fabric, The particle size is 10 to 500 μm It can be produced by applying a surface coating agent comprising a matrix material having inorganic particles and / or organic particles as a dispersed phase and a binder as a continuous phase, using a coating machine.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the production method of the herbicidal sheet, the surface coating agent for the herbicidal sheet and the herbicidal sheet of the present invention will be described in detail. Hereinafter, “%” representing a blending unit in this specification is a mass unit unless otherwise specified.
[0015]
As shown in FIG. 1, the weedproof sheet 42 of the present invention is basically characterized in that a non-woven fabric 34 formed by press-bonding long fibers is used as a base material. By pressure-bonding the long fibers, the fiber density of the weedproof sheet 42 becomes very high, and weed growth can be prevented. Furthermore, since the fiber density of the sheet is high, it is possible to sufficiently cope with the problem of sheet breakage due to protrusions and the like at the laying site.
[0016]
Natural fiber (plant fiber, animal fiber, mineral fiber) and chemical fiber (inorganic fiber, regenerated fiber, semi-synthetic fiber, synthetic fiber) can be used as the material of the above-mentioned long fiber. From the standpoint of sex, continuous filaments of synthetic fibers are usually used.
[0017]
Examples of the synthetic fibers include polyolefin fibers such as polypropylene and polyethylene, polyester fibers such as polyethylene terephthalate, polytrimethylene terephthalate and polybutylene terephthalate, polyamide fibers such as nylon, acrylic fibers such as acrylonitrile, and other, polyvinyl alcohol. Fiber, polyvinyl chloride fiber, polyvinylidene chloride fiber, modacrylic fiber, fluorocarbon fiber, polyurethane fiber, etc. can be used singly or in combination, but the weather resistance and cost can be reduced. In consideration, it is preferable to use a polyester fiber, particularly polyethylene terephthalate.
[0018]
As the long fiber, one having an average fineness of about 1.1 to 15.4 dtex (dg / km), preferably about 2.2 to 12.1 dtex, more preferably about 3.3 to 7.7 dtex may be used. desirable. If the average fineness is too large, the projection plane porosity described later is increased, and the light transmittance of the nonwoven fabric 34 is increased to help the growth of weeds. On the other hand, if it is too small, the projected plane porosity is lowered and the light shielding effect is increased, but the water permeability is deteriorated, which is not preferable.
[0019]
The pressure-bonding means that the material is pressed and bonded by a pressure roller such as a smooth calender roll or engraving roll, and may be bonded only by the pressure of the above-mentioned various rolls. An adhesive such as an adhesive or a fibrous adhesive may be used in combination. In addition, after mechanical entanglement by a needle punch method, a stitch method, a spun lace method, or the like may be applied, press contact may be performed with the various rolls.
[0020]
As the nonwoven fabric 34 (base material) formed by the pressure-bonding adhesion, for example, the nonwoven fabric described in Japanese Patent Publication No. 4-52727 can be suitably used. More specifically, the weight per unit area is about 30 to 500 g / m. ² , Preferably about 40 to 350 g / m ² More desirably, about 100 to 300 g / m ² And If the mass per unit area is too small, the number of fibers constituting the nonwoven fabric 34 is small, and the light shielding property and the penetration resistance of weeds are low, so that the initial purpose cannot be achieved. On the other hand, if the amount is too large, the herbicidal effect is high and there is no problem, but the water permeability and air permeability become low. Moreover, when producing with a pressure roll, it is necessary to increase the pressure load of the pressure roll, which increases production problems, increases costs, increases mass, and makes construction difficult.
[0021]
The nonwoven fabric density is about 0.1 g / cm ^Three Or more, preferably about 0.2 g / cm ^Three More preferably, about 0.25 g / cm ^Three As described above, the projected plane porosity is about 0.01 to 0.1%, desirably about 0.02 to 0.09%, more desirably about 0.03 to 0.08%, and the penetration resistance is desirably 5 kg or more. Is 6 kg or more, more desirably 8 kg or more. In order to satisfy this condition, not only the weight per unit area is important, but also the fineness of the synthetic long fibers to be formed and the roll pressure contact conditions can be controlled appropriately.
[0022]
Here, the projected plane porosity is calculated by a measurement method described later.
[0023]
In addition, the said nonwoven fabric 34 should just form the above-mentioned long fiber as a main body, and may mix a middle fiber and a short fiber in the range which cannot show | play the effect of this invention. Such a nonwoven fabric sheet is generally stronger and harder to deform than a short fiber nonwoven fabric sheet, so that the penetration resistance of weeds is increased, and weed prevention can be performed efficiently.
[0024]
The herbicidal sheet 42 of the present invention has a coating film made of a matrix material having inorganic particles and / or organic particles 13 as a dispersed phase and a binder (resin binder) 15 as a continuous phase on the surface of the nonwoven fabric 34. The layer 17 is formed. The durability of the weedproof sheet 42 can be improved by forming the coating layer 17 using a matrix material having inorganic particles and / or organic particles 13 as a dispersion layer and a binder 15 as a continuous phase. Furthermore, slip resistance can be imparted to the weedproof sheet 42. The weedproof sheet 42 has a coefficient of friction of about 0.5 to 0.8, preferably about 0.6 to 0.7.
The coating film layer 17 may be formed on at least one side of the nonwoven fabric 34 (the side that becomes the upper side when laid), but may be formed on both sides. In addition, the inorganic particles and / or the organic particles 13 may protrude from the surface as illustrated in FIG. 1 or may be embedded in the binder 15.
[0025]
In the above case, the surface coating agent for a herbicidal sheet having the following constitution of the present invention can be used.
[0026]
A surface coating agent used by being applied to the surface of the herbicidal sheet 42, the matrix coating material having inorganic particles and / or organic particles 13 as a dispersed phase and binder 15 as a continuous phase. It is formed by.
[0027]
As the inorganic particles and / or organic particles 13, when a recycled material is used, it is possible to obtain an environmentally friendly weedproof sheet 42, which is economical. The recycling material can be used without any particular limitation as long as the waste can be reused. For example, in the case of inorganic particles, concrete, wall materials, tiles, and other waste materials from construction demolition sites, etc., powders of metal and other waste materials generated when dismantling automobiles, etc. Shells, glass pieces, ceramic pieces, etc. that have been disposed of as trash can be crushed or sand particles.
[0028]
More specifically, examples thereof include aluminum silicate, calcium carbonate, calcium silicate, aluminum hydroxide, silica, mica, carbon, metal powder, and the like.
[0029]
In the case of organic particles, recycled products such as various waste rubbers and waste plastics, and powdered other waste materials can be used. These may be used as a mixture of plural kinds or as a single kind.
[0030]
The size of the inorganic particles and / or organic particles 13 used above is about 10 to 500, preferably about 20 to 300 μm, and more preferably about 30 to 100 μm. If the size of the inorganic particles and / or the organic particles 13 is too small, the slip resistance is deteriorated. On the other hand, if it is too large, the coating property when producing the herbicidal sheet 42 is deteriorated as will be described later, and the particles fall off during use.
[0031]
From the viewpoint of the production process and cost, it is preferable to use silica as the inorganic particles and to use recycled products of waste rubber and plastic as the organic particles.
[0032]
The binder 15 is usually in a solution form or an emulsion (latex) form, but an emulsion form is usually used. Specifically, acrylic resin binders such as acrylic acid, methacrylic acid, homopolymers of acrylic esters or other monomers and copolymers, polyvinyl acetate, polyvinyl chloride, polyvinyl alcohol (PVA), ethylene-acetic acid Examples thereof include vinyl resin binders such as vinyl copolymer (EVA), rubber binders such as styrene-butadiene rubber and acrylonitrile-butadiene rubber.
[0033]
Among the above, in terms of durability, production conditions, and cost, it is preferable to use an acrylic resin binder, particularly a copolymer of styrene and an acrylic monomer. Since the acrylic resin binder is rich in flexibility and less discolored by heat, ultraviolet rays, etc., a considerable amount of flame retardant can be mixed as described later without deteriorating the physical properties of the herbicidal sheet 42. It is.
[0034]
The blending amount of the inorganic particles or the organic particles 13 is about 30 to 80%, desirably about 40 to 80%, more desirably about 50 to 80% with respect to the binder 15. When the amount is too large, the coating property on the surface of the nonwoven fabric is deteriorated, and particle dropout easily occurs during use, which is not preferable. Moreover, when there are too few compounding quantities, since water permeability and air permeability worsen and slip resistance will also worsen, it is unpreferable.
[0035]
The surface coating agent is a matrix material having inorganic particles and / or organic particles 13 as a dispersed phase and binder 15 as a continuous phase. The matrix material can be produced simply by mixing the binder 15 with inorganic particles and organic particles 13.
[0036]
And it is desirable to make the said surface coating agent for grass prevention sheets contain a flame retardant further. As the above flame retardant,
Phosphate ester, tricresyl phosphate (TCP), triphenyl phosphate (TPP), trixylene phosphate (TXP), chlorinated organic polyphosphate, trichloropropyl phosphate (TCPP), chlorinated organic phosphate Phosphorus compounds such as
Halogenated hydrocarbon, chlorinated polyethylene, chlorinated paraffin, chlorinated hydrocarbon, brominated organic (aromatic), 1,1,2,2-tetrabromoethane (TBE), 1,2,3,4-tetra Halogenated compounds such as bromobutane (TBB), 1,2,3-tribromopropane (TBP), brominated polymer compounds,
Other organic substances such as trialkyl-boron-ester, ethylene-vinyl chloride-latex, etc.
Inorganic substances such as aluminum hydroxide, antimony trioxide, ammonium-fluoroborate, sodium antimonate, barium metaborate, zinc borate, ammonium orthophosphate,
Can be illustrated.
[0037]
Of these, non-halogen compounds such as aluminum hydroxide can be preferably used.
[0038]
As the blending ratio of the flame retardant, the range of about 5 to 50% is effective, desirably about 10 to 40%, and more desirably about 20 to 30%.
[0039]
The coating thickness of the surface coating agent is about 30 to 500 μm, preferably about 40 to 300 μm, more preferably about 60 to 150 μm. If the coating thickness is too thin, it is difficult to obtain the effect of the present invention. Conversely, if the coating thickness is too thick, the water permeability of the weedproof sheet 42 decreases.
[0040]
In the flame retardant treatment of the herbicidal sheet 42 of the present invention, methods other than the method of mixing the flame retardant with the inorganic particles and the organic particles 13 in the binder 15 as described above can also be used.
[0041]
For example, it is difficult to use a flame retardant resin as a raw material for long fibers, to press and bond a flame retardant together during molding of a nonwoven fabric, to bond inorganic particles and organic particles 13, and to mix with a binder 15. It is conceivable to apply a coating agent containing a flame retardant.
[0042]
Next, the manufacturing method of the said weed prevention sheet 42 is demonstrated. The herbicidal sheet 42 of the present invention directly forms an aggregate of continuous filaments from a heat-melted synthetic resin, and after forming the nonwoven fabric 34 by a spunbond method in which pressure welding is performed using a pressure-contacting roll, It can be produced by applying a surface coating agent made of a matrix material having inorganic particles and / or organic particles 13 as a dispersed phase and binder 15 as a continuous phase, using a coating machine.
[0043]
Here, the spunbond method is a method for producing the nonwoven fabric 34 in which spinning, drawing, stacking, adhesion, and winding on a roll are combined in one step.
[0044]
Hereinafter, each process of the said spun bond method is demonstrated based on drawing. FIG. 2 is a process schematic diagram until a nonwoven fabric 34 (base material) is manufactured using a synthetic resin as a raw material. mainly,
(1) A melt extrusion process in which synthetic resin is melted and extruded to form long fibers (continuous fibers).
(2) A continuous filament forming process in which the resin extruded in the melt extrusion process is formed into a filament,
(3) A web forming process for forming a web (aggregate) from continuous filaments,
(4) Filament bonding step in which the webs are pressed and bonded between the continuous filaments to form a nonwoven fabric 34;
Consists of.
[0045]
The conditions for extruding the synthetic resin vary depending on the type of resin used, but may be the same as the conditions for producing ordinary fibers. Specifically, a synthetic resin is charged into a hopper (resin charging portion) 14 of an extruder (extruder) 12 and melted by heat, and then the molten resin is extruded from a spinneret 18 by a gear pump 16. The filament 20 melt-spun from the spinneret 18 is drawn by the lower ejector 22 and sent downward. By applying static electricity to the ejector 20, the filaments are charged and spread uniformly, and are collected on the lower belt conveyor 24 by a suction machine 26, and a random long fiber web 28 is obtained.
[0046]
The webs 28 are joined by press-bonding using the press rolls 30 and 30 in the press machine 29. At that time, a flat roll, an embossing roll, or the like can be used as the pressure contact roll 30. Adhesion may be used in combination, although adhesion may be performed only by the pressure contact of the pressure roll 30. Further, after mechanical entanglement is given by a needle punch method, a step method, a spin race method, or the like, the press contact roll 30 may be used for press contact.
[0047]
FIG. 3 shows an embossing roll 30a and a flat roll 30b that can be applied as the pressure contact roll 30. In FIG. 3, the embossing roll 30a is used on the upper surface side and the flat roll 30b is used on the lower surface side. However, the opposite may be used, or both types of pressure contact rolls may be used.
[0048]
When using polyethylene terephthalate resin, etc., the fibers are self-bonded by sufficient thermocompression bonding, and the fiber density of the sheet becomes very high, blocking sunlight by 99% or more and preventing weed growth. It becomes possible to do. Furthermore, since the fiber density of the sheet is high, it is difficult to cause a problem such as sheet breakage due to protrusions or the like at the laying site.
[0049]
The non-woven fabric 34 manufactured as described above is taken up by the take-up roller 32 and subjected to surface coating by the following application process.
[0050]
FIG. 4 shows an application process in which a surface coating agent is applied to the surface of the nonwoven fabric 34. The surface coating agent is a matrix material obtained by mixing inorganic particles and / or organic particles 13 with a binder 15 as described above. In addition, a flame retardant may be further contained.
[0051]
When coating the surface coating agent, a conventional coating apparatus (coating machine) such as a gravure coater, roll coater, knife coater, etc. can be used as a coating method.
[0052]
Of these, the knife coater 36 can be preferably used as shown in FIG. This is because the desired coating thickness can be easily obtained. The knife coater machine has a supply nozzle 40 for supplying a surface coating agent to the front side of the coating knife 38, so that continuous coating is possible.
[0053]
And the coating-film layer 17 is firmly formed in the surface of the nonwoven fabric 34 by allowing the heat setting machine 44 etc. to pass through. The coated grass protection sheet 42 is wound around a winding roller 48 of a winder 46 to obtain a final product.
[0054]
In addition, the weedproof sheet of this invention is not limited only to what was manufactured with the said manufacturing method.
[0055]
Finally, the method for measuring the projected plane porosity in this specification is described for reference.
[0056]
<How to sample>
The non-woven fabric is watermarked with transmitted light, and a low-weighted portion and a high-weighted portion are selected from the average and marked respectively. 10mm from the marking part using a ruler and cutter ² Four samples are collected from each of the low weight portion and the high weight portion.
[0057]
<Measurement method>
Using an optical microscope (magnification: 100 times, light source 6V, 30W), the size of the gap through which light passes is measured with a microscope scale. Since the void is irregular, the average major axis and the minor minor axis of the irregular void are measured, and the average value is obtained as the size of the void. The entire surface of the sample piece is inspected, and the number of voids having a size of 10 or more is counted in a size of 5 units (the size is determined by rounding off).
[0058]
<Calculation method>
The void area is Σ ((each size) ² X (number of sizes)). Projection plane
The void ratio is obtained as a percentage by dividing the void area calculated as described above by the sample area. The average value of 4 samples is calculated | required and it is set as the projection average porosity of the nonwoven fabric.
[0059]
【The invention's effect】
The herbicidal sheet of the present invention has a high light-shielding effect, and can exert a strong herbicidal effect that can prevent breakthrough even for plants with high vitality, such as rice. . In addition, seeds flying on the surface are not substantially settled and have water permeability and air permeability, so that they do not hinder the growth of surrounding trees and plants.
[0060]
Moreover, there is no accumulation of water due to rain or the like, and even if the ground becomes soft, no soil or water is ejected to the surface. Moreover, it is excellent in durability (year in which it can be used). Furthermore, when walking on a grass-proof sheet installed on an inclined bank, the surface is hard to slip, so it does not fall down and is safe.
[0061]
Further, by applying a flame retardant treatment, it is possible to prevent the occurrence of perforation due to burning even if the cigarette butts are thrown away.
[0062]
【Example】
Examples carried out to confirm the effects of the present invention will be described below.
[0063]
<Example>
A polyethylene terephthalate resin is melted at an intrinsic viscosity of 0.65 at a melting temperature of 290 ° C., spun at 2.5 g / min per single hole from the die hole, and taken up at a spinning speed of 4800 m / min by an air take-off method. It was collected on a conveyor as a long fiber nonwoven web. A long-fiber nonwoven fabric sheet was obtained by pressure-bonding the web at a temperature of 230 ° C. and a linear pressure of 20 kg / cm using a pair of thermal engraving rolls having a pressure contact area of 16%.
[0064]
The resulting sheet is
Mass per unit area: 130 g / m ² Sheet density: 0.26 g / cm ^Three , Constituent fiber average fineness: 3.8 dtex,
Met.
[0065]
As the surface coating agent, 70% of inorganic particles of silica containing styrene acrylic as a main ingredient and 30% of aluminum hydroxide as a flame retardant were kneaded on one side of the substrate with a knife coating machine. In this case, the thickness of the surface coating agent was 120 microns. The coating surface was dried at 170 ° C.
[0066]
<Comparative example>
A polyethylene terephthalate resin is melted at an intrinsic viscosity of 0.65 at a melting temperature of 290 ° C., spun at 2.5 g / min per single hole from the die hole, and taken up at a spinning speed of 4800 m / min by an air take-off method. It was collected on a conveyor as a long fiber nonwoven web. A long-fiber nonwoven fabric sheet was obtained by pressure-bonding the web at a temperature of 230 ° C. and a linear pressure of 20 kg / cm using a pair of thermal engraving rolls having a pressure contact area of 16%.
[0067]
The resulting sheet is
Mass per unit area: 130 g / m ² Sheet density: 0.26 g / cm ^Three , Constituent fiber average fineness: 3.8 dtex
Met.
[0068]
The physical properties of the herbicidal sheets of the above Examples and Comparative Examples were evaluated. The results are shown in Table 1.
[0069]
[Table 1]

[0070]
<Method for testing herbicidal properties>
The grass protection sheets of Examples and Comparative Examples were laid outdoors to evaluate the grass protection performance. The laying conditions were 18 months from April to the following October, and the place was in Chiba Prefecture.
[0071]
As a result, it was confirmed that grass was not grown on the part where the herbicidal sheet was laid in both Examples and Comparative Examples (evaluation ◎) and good herbicidal properties were obtained.
[0072]
<Durability (light resistance) test method>
After irradiating light for 100 h, 300 h, and 400 h using a strong energy sunshine fade meter (manufactured by Suga Test Instruments Co., Ltd., SEL-1 type), the tensile strength was measured and the tensile strength retention rate was measured.
[0073]
Tensile strength retention rate (%) = Tensile strength after light irradiation (N) / Tensile strength before light irradiation (N)
The results are shown in FIG.
[0074]
From FIG. 5, it can be seen that the herbicidal sheet of the example has a tensile strength retention ratio of 5 times or more as compared with the comparative herbicidal sheet and has good light resistance.
[0075]
In the herbicidal sheet of the examples, the tensile strength before light irradiation (length: 584 N / 5 cm, width: 319 N / 5 cm), elongation (length: 83.5%, width: 86.0%), It has been confirmed that the tear strength (length: 37.3N, width: 39.2N) and any numerical values are suitable as a herbicidal sheet.
[0076]
<Anti-slip test method>
Using the anti-slip test apparatus shown in FIG.
[0077]
(1) Take only 3 horizontal 16 cm × 9 cm test pieces.
[0078]
(2) The test piece 50 is fixed with double-sided tape with the coating surface facing up on the mount (be careful not to wrinkle).
[0079]
(3) The mount is fixed to the measurement plate 52 with double-sided tape.
[0080]
(4) Level the measurement plate 52 and gently place a 50 g weight 54 in the center of the test piece 50 (confirm horizontal with the scale of the protractor 56).
[0081]
(5) The measurement plate 52 is slowly moved downward to read the angle at which the weight 54 starts to move (read the scale of the protractor 56).
[0082]
As a result, the weight control sheet of the comparative example began to slide when the inclination was about 20 ° (evaluation ×), whereas the weight prevention sheet of the example had a weight of about 30 ° (evaluation ◎). I didn't slide out. Therefore, it turns out that the anti-slip property of the anti-slip sheet of the present invention is very good as compared with the anti-weed sheet of the comparative example.
[0083]
<Permeability test method>
The hydraulic conductivity was measured according to JIS A 1208. The measured water temperature was 15 ° C.
[0084]
As a result, the hydraulic conductivity of the comparative herbicidal sheet was 1.1 × 10. ^-2 Whereas it was cm / sec (evaluation ◎), the weedproof sheets of the examples had a water permeability of 3.3 × 10. ^-Four Although cm / cec (evaluation (circle)) and water permeability are somewhat inferior, it turns out that it is a sufficient evaluation value as a weed prevention sheet.
[0085]
<Breathability test method>
The weedproof sheets of Examples and Comparative Examples were applied to the mouth, and each breath was blown strongly through the mouth to determine whether air passed through the back surface. As a result, while the comparative herbicidal sheet allows air to pass through (evaluation ◎), the herbicidal sheet of the example is slightly inferior in air permeability (evaluation ○), but with a sufficient evaluation value as a herbicidal sheet I know that there is.
[0086]
<Flame retardance test method>
Judgment was performed according to the JIS L 1091 textile product combustion test method (Method B). As a result of performing a combustion test using an air mix burner, the comparative herbicidal sheet has a residual flame time of 0 sec and a combustion length (carbonization length) of 3.3 cm (evaluation Δ). After flame time 0 sec, combustion length (carbonization length) 2.7 cm (evaluation ｃｍ), it can be seen that the flame retardancy is very good.
[Brief description of the drawings]
FIG. 1 is a cross-sectional model view showing a weedproof sheet of the present invention.
FIG. 2 is a schematic view showing a process for producing a nonwoven fabric which is a base material of the herbicidal sheet of the present invention.
FIG. 3 is a schematic view of a pressure roller used for pressure bonding of a nonwoven fabric.
FIG. 4 is a process schematic diagram of a process of applying a surface coating agent to a substrate (nonwoven fabric).
FIG. 5 is a graph showing the results of the light resistance test in Examples.
FIG. 6 is a schematic view of an apparatus used for a slip resistance test.
[Explanation of symbols]
12: Extruder
13: Inorganic particles and / or organic particles
15: Binder
18: Spinneret
20: Filament
24: Belt conveyor
28: Web
29: Pressure welding machine
30: Pressure contact roll
34: Nonwoven fabric
36: Knife coater machine
42: Grass protection sheet
44: Heat set machine

Claims (8)

In a herbicidal sheet based on a nonwoven fabric formed by pressure-bonding long fibers, inorganic particles and / or organic particles having a particle diameter of 10 to 500 μm are dispersed on the surface of the nonwoven fabric, and a binder is continuously provided. A herbicidal sheet comprising a coating layer made of a matrix material as a phase. The weedproof sheet according to claim 1, wherein the density of the nonwoven fabric is 0.2 g / cm ³ or more and less than 0.3 g / cm ³ . The herbicidal sheet according to claim 1 or 2 , wherein a flame retardant treatment is applied to the herbicidal sheet by adding a flame retardant to the matrix material.   The weedproof sheet according to claim 1, 2 or 3, wherein the inorganic particles and / or organic particles are recycled materials. A method for producing a herbicidal sheet comprising a nonwoven fabric formed from long fibers as a base material, and a coating layer containing inorganic particles and / or organic particles is formed on the surface of the nonwoven fabric,
  A continuous filament assembly is directly formed from a heat-melted synthetic resin, and the nonwoven fabric is formed by a spunbond method in which pressure welding is performed using a pressure roll, and then the surface of the nonwoven fabric has a particle diameter of 10 to 500 μm. A method for producing a herbicidal sheet, wherein a surface coating agent comprising a matrix material having inorganic particles and / or organic particles as a dispersed phase and a binder as a continuous phase is applied using a coating machine. The nonwoven fabric has a density of 0.2 g / cm. ^Three 0.3 g / cm ^Three The method for producing a herbicidal sheet according to claim 5, wherein Furthermore, the weedproof sheet after application | coating with the said coating machine is passed through a heat setting machine, The manufacturing method of the weedproof sheet of Claim 5 or 6 characterized by the above-mentioned . The method for producing a herbicidal sheet according to claim 5, 6 or 7, wherein the surface coating agent further contains a flame retardant.

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