CN112261870B

CN112261870B - Grass-proof sheet and method for producing grass-proof sheet

Info

Publication number: CN112261870B
Application number: CN201980001378.4A
Authority: CN
Inventors: 宫崎幸辅
Original assignee: Seiren Co Ltd
Current assignee: Seiren Co Ltd
Priority date: 2019-05-21
Filing date: 2019-05-21
Publication date: 2021-10-22
Anticipated expiration: 2039-05-21
Also published as: WO2020235001A1; CN112261870A; JPWO2020235001A1; KR102103683B1; JP6634190B1

Abstract

The invention provides a grass-proof sheet which has a structure that is not easy to damage and can improve light-shielding performance. A grass protection sheet (1) having a twill weave or satin weave including a front side ground weave (10), a back side ground weave (20), and weft yarns (31), wherein the front side ground weave (10) includes first warp yarns (11), the back side ground weave (20) includes second warp yarns (21), and the weft yarns (31) connect the front side ground weave (10) and the back side ground weave (20) to form a warp double weave, and is configured such that: the first warp (11) is a twisted yarn containing a black spun dyed yarn, the weft (31) is a yarn containing a black spun dyed yarn, and the twist direction of the first warp (11) coincides with the twill grain direction expressed by the surface side base weave (10).

Description

Grass-proof sheet and method for producing grass-proof sheet

Technical Field

The present invention relates to a grass-repellent sheet having a twill weave or satin weave including a front-side ground weave including first warp yarns, a back-side ground weave including second warp yarns, and weft yarns connecting the front-side ground weave and the back-side ground weave to form a warp double weave, and a method for manufacturing the grass-repellent sheet.

Background

The grass-control sheet has a luxuriant grass-control effect of blocking light irradiated to soil and suppressing the proliferation of plants, and is used for maintaining the beauty of the surroundings of trees in buildings and streets, or for adjusting the growing environment of fruit trees and vegetables by directly spreading the grass-control sheet on the cultivation ground in orchards, vegetable gardens, and the like.

Conventionally, as a grass-control sheet, a method of laying a plastic sheet, a rubber-coated fabric sheet, or the like on soil has been employed, but since the plastic sheet or the rubber-coated fabric sheet does not have water permeability and water such as rainwater does not permeate into the ground, when the sheet is laid between trees, there is a problem that the soil dries and the trees wither. In order to solve such a problem, in recent years, as the grass-proof sheet, a fabric such as a nonwoven fabric or a woven fabric has been used from the viewpoint of water permeability.

For example, there is a grass-control sheet composed of a double-weave fabric (see, for example, patent document 1). The grass-control sheet of patent document 1 has water permeability due to its fabric structure, and can prevent the growth of plants while suppressing the drying of soil.

There is a grass-protection sheet having a joint portion that joins a front surface layer and a back surface layer, and a non-joint portion that does not join the front surface layer and the back surface layer (see, for example, patent document 2). The grass-protective sheet of patent document 2 has sufficient light-shielding properties and improved weather resistance and the like by spreading the joints.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2004-73146

Patent document 2: international publication No. 2016/039266 pamphlet

Disclosure of Invention

Problems to be solved by the invention

Although the grass-protective sheet of patent document 1 has a light-shielding rate of 99% (see example 2), it is necessary to further improve the light-shielding property in order to completely suppress the blooming of plants below the sheet.

The grass-repellent sheet of patent document 2 has a surface layer and a back layer to achieve high light-shielding properties, but if there are many unbonded portions where both layers are completely separated, slippage occurs between the surface layer and the back layer, and there is a possibility that the cloth may be damaged at the bonded portions.

The present invention has been made in view of the above problems, and an object thereof is to provide a grass-protection sheet having a structure that is less likely to be damaged and capable of improving light-shielding properties, and a method for manufacturing the grass-protection sheet.

Means for solving the problems

The grass-preventive sheet of the present invention for solving the above problems is characterized in that,

the grass-control sheet has a twill weave or a satin weave including a front-side ground weave including first warp yarns, a back-side ground weave including second warp yarns, and weft yarns connecting the front-side ground weave and the back-side ground weave to form a warp double weave,

the grass-prevention sheet is configured as follows:

the first warp yarn is a twisted yarn comprising a black spun dyed yarn,

the weft yarns are yarns comprising black spun dyed yarns,

the twist direction of the first warp is consistent with the twill grain direction expressed by the surface side base weave.

According to the grass-control sheet of this structure, the following structure is provided: the warp double weave structure has a twill weave or a satin weave including a front side ground weave including first warp yarns, a back side ground weave including second warp yarns, and weft yarns connecting the front side ground weave and the back side ground weave to form a warp double weave, and thus has no region where the front side ground weave and the back side ground weave are completely separated, and does not slide between the front side ground weave and the back side ground weave, and is less likely to be broken. Further, the present inventors have made various grass-repellent sheets by variously changing the structure and the use of yarns, and have found that, when the twist direction of the warp yarn coincides with the twill grain direction expressed in the structure, a force in the twist return direction acts on the warp yarn during weaving, and the obtained grass-repellent sheet slightly returns the twist, so that the apparent thickness of the warp yarn increases, and a gap is less likely to be formed between adjacent warp yarns. Accordingly, the present inventors have utilized this phenomenon to complete a grass-control sheet having more excellent light-blocking properties than conventional grass-control sheets. That is, according to the grass-repellent sheet of this configuration, the first warp yarns are twisted yarns including black spun dyed yarns, the weft yarns are yarns including black spun dyed yarns, and the twisting direction of the first warp yarns coincides with the twill grain direction expressed in the front side ground weave, so that the occurrence of gaps between adjacent first warp yarns in the front side ground weave is suppressed. As a result, the light-shielding property of the grass-protection sheet can be improved.

In the grass-protective sheet of the present invention,

preferably, in the front side ground weave, when a twill angle formed by a line connecting intersections where the weft yarns are exposed and a warp yarn direction is α and a twist angle of the first warp yarn of the front side ground weave is β, the following expression (1) is satisfied:

|(α-β)/α|×100≤70···(1)。

according to the grass-repellent sheet having the above configuration, since the above equation (1) is satisfied, when the twist of the first warp yarn rebounds, the gap between the adjacent first warp yarns is reliably filled, and the light-shielding property can be further improved.

In the grass-protective sheet of the present invention,

preferably, the first warp yarn has a twist multiplier of 0.3 to 4.

According to the grass-control sheet having the above configuration, since the twist factor of the first warp is 0.3 to 4, the twist is appropriately rebounded during weaving, and thus the light-shielding property can be further improved.

In the grass-protective sheet of the present invention,

preferably, the weft yarns are non-shrinkable yarns.

According to the grass-repellent sheet having the above-described structure, since the weft is a non-shrinkable yarn, shrinkage with time is suppressed, and thus, excellent workability can be obtained.

In the grass-protective sheet of the present invention,

preferably, the grass-control sheet has a cover factor of 4000 or more.

According to the grass-repellent sheet having the above-described structure, since the cover factor is 4000 or more, the grass-repellent sheet becomes a high-density woven fabric, and light can be prevented from passing between the single yarns constituting the warp and the weft, thereby further improving the light-shielding property.

In the grass-protective sheet of the present invention,

preferably, the weft yarn is composed of a yarn having the same thickness as or greater than the first warp yarn.

According to the grass-protective sheet of this configuration, since the weft yarn is made of a yarn having the same thickness as or greater than the first warp yarn, the arching of the first warp yarn of the front-side ground weave is lengthened, and therefore the gap between adjacent first warp yarns is filled, and the light-shielding property can be more effectively improved.

In the grass-protective sheet of the present invention,

preferably, the first warp yarn, the second warp yarn, and the weft yarn are each at least one selected from the group consisting of a polyester yarn, a polyolefin yarn, and a polyamide yarn.

According to the grass-control sheet having the above-described structure, excellent strength and weather resistance can be achieved by using the yarn.

In the grass-protective sheet of the present invention,

preferably, the surface-side base structure is made of a satin weave.

According to the grass-repellent sheet having the above-described configuration, since the front-side ground weave is made of a satin weave, the arching of the first warp yarns of the front-side ground weave is increased, and therefore, the gaps between the adjacent first warp yarns are filled up, and the light-shielding property can be more effectively improved.

The method for producing a grass-repellent sheet according to the present invention for solving the above problems is characterized in that,

the grass-control sheet has a twill weave or satin weave which is formed by connecting a front-side ground weave including first warp yarns and a back-side ground weave including second warp yarns with weft yarns to form a warp double weave,

in the method of manufacturing the grass-preventive sheet,

using a twisted yarn comprising a black spun dyed yarn as the first warp yarn,

using a yarn comprising a black spun dyed yarn as the weft yarn,

the weft yarns are woven between the front side base weave and the back side base weave so that the twist direction of the first warp yarns coincides with the twill grain direction expressed in the front side base weave.

According to the method for manufacturing the grass-repellent sheet having the above structure, the grass-repellent sheet having the following structure can be manufactured: the warp knitting machine has a twill weave or a satin weave in which a front side ground weave including first warp yarns and a back side ground weave including second warp yarns are connected by weft yarns to form a warp double weave, has no region where the front side ground weave and the back side ground weave are completely separated, and is less likely to be broken because no slip occurs between the front side ground weave and the back side ground weave. In addition, according to the method for producing a grass-repellent sheet having the above configuration, the twisted yarn including the black spun dyed yarn is used as the first warp, the yarn including the black spun dyed yarn is used as the weft, and the weft is woven between the front side ground weave and the back side ground weave so that the twist direction of the first warp coincides with the twill grain direction expressed in the front side ground weave, thereby suppressing the occurrence of a gap between the adjacent first warps in the front side ground weave. As a result, a grass-preventive sheet having improved light-shielding properties can be produced.

Drawings

Fig. 1 is an explanatory view of the grass-preventive sheet of the present invention.

FIG. 2 is an example of a structure diagram of the grass-preventive sheet of the present invention.

Fig. 3 is a top view of a face side base weave woven with twill weave.

Fig. 4 is a microscope image of the grass-repellent sheets of examples and comparative examples, the surface side base structure being photographed.

Detailed Description

The following describes the grass-control sheet and the method for producing the grass-control sheet of the present invention. However, the present invention is not intended to be limited to the following structures.

< grass-preventive sheet >

Fig. 1 is an explanatory view of a grass-preventive sheet 1 of the present invention. Fig. 1 (a) is a perspective view of a part of the grass-repellent sheet 1, fig. 1 (b) is a plan view of a part of the front-side ground weave 10, and fig. 1 (c) is an enlarged plan view of a part of the first warp yarns 11. The grass-repellent sheet 1 includes a front side ground weave 10 including first warp yarns 11, a back side ground weave 20 including second warp yarns 21, and weft yarns 31 connecting the front side ground weave 10 and the back side ground weave 20 to form a warp double weave. By forming the double-layer structure, there is no region where the front-side base structure 10 and the back-side base structure 20 are completely separated, and the structure is not easily broken, and has excellent light-shielding properties and durability. The volume density of the grass-control sheet 1 is preferably 0.30g/cm³Above, more preferably 0.35g/cm³The above. For example, thatch or cedar sprouts grow from transverse-climbing rhizomes, thus enabling even layingThe area is shielded from light, and a bud having a high penetration force may be ejected from the lower side of the grass-control sheet 1. The buds of herba Imperatae or herba Cunninghamiae Lanceolatae are hard and sharp, but if the volume density is 0.30g/cm³As described above, the weed-control sheet 1 becomes dense, and the shoot tips of the thatch or cedar can be prevented from penetrating.

< surface-side base texture >

Fig. 2 is an example of a structure diagram of the grass-control sheet 1. Referring to fig. 1 (a), in fig. 2, the first warp yarns 11 constituting the front side ground weave 10 are shown in black in odd-numbered columns, the second warp yarns 21 constituting the back side ground weave 20 are shown in black in even-numbered columns, and the weft yarns 31 are shown in white in each column. As shown in odd-numbered columns in the weave diagram of fig. 2, the surface-side base weave 10 is woven using the first warp yarn 11 and the weft yarn 31. The weave structure of the front side ground weave 10 is a regular twill weave and its modified weave (hereinafter, simply referred to as "twill weave") or a regular satin weave and its modified weave (hereinafter, simply referred to as "satin weave") that can obtain a high-density weave, and as described later, in order to fill the gaps between adjacent first warp yarns and realize a structure that more effectively improves the light-shielding property, the satin weave is preferable, and 7 or more satin weaves are more preferable. Fig. 1 shows an example in which the front-side ground weave 10 is formed of 7 satin weaves. The warp density of the surface side base weave 10 is preferably 100 to 200 pieces/2.54 cm. The weft density is preferably 50-150 pieces/2.54 cm. If the warp density and the weft density are in this range, the front side foundation weave 10 has a relatively dense structure, and light transmission between the first warp 11 and the weft 31 can be substantially completely suppressed. When the warp density is less than 100 threads/2.54 cm or when the weft density is less than 50 threads/2.54 cm, the light transmission between the yarns may not be substantially completely suppressed. In addition, when the warp density exceeds 200 pieces/2.54 cm, or when the weft density exceeds 150 pieces/2.54 cm, the flexibility of the grass-protection sheet 1 may be impaired.

The first warp yarn 11 is a twisted yarn including a black spun dyed yarn in a single yarn. The inclusion of the black spun dyed yarn improves the light-shielding property and suppresses the bloomeness of plants under the sheet. The black spun dyed yarn is excellent in durability and weather resistance compared with the case where the color tone is given by dyeing, printing, or the like, and therefore can be suitably used for the grass-repellent sheet 1 laid outdoors. As the fiber material of the first warp yarn 11, polyester-based fibers such as polyethylene terephthalate and polybutylene terephthalate; polyamide fibers such as nylon 6, nylon 66, and nylon 46; and synthetic fibers such as polyolefin fibers including polyethylene and polypropylene. By using these materials, excellent strength and weather resistance can be obtained. The total fineness of the first warp yarns 11 is preferably 77 to 330dtex, and the single yarn fineness of the first warp yarns 11 is preferably 1.0 to 5.0 dtex. If the total fineness and the single yarn fineness are within the above ranges, the grass-control sheet 1 has good flexibility and can improve workability during construction. When the total fineness of the first warp yarn 11 is less than 77dtex, or when the single-yarn fineness of the first warp yarn 11 is less than 1.0dtex, the strength of the grass-protection sheet 1 may be poor. In addition, when the total fineness of the first warp yarn 11 exceeds 330dtex, or when the single yarn fineness of the first warp yarn 11 exceeds 5.0dtex, the flexibility of the grass-protection sheet 1 may be impaired.

Fig. 3 is a plan view of the surface-side base structure 10 woven with twill weave. The twist direction of the first warp yarn 11 is configured to be aligned with the twill grain direction expressed in the front-side base structure 10. Here, the "twill grain direction" refers to a direction in which, in a satin weave, as shown in fig. 1 (b), when the front surface side ground weave 10 is viewed in plan view, the woven weft yarns 31 are connected in order to expose the centers 31a of the intersections (hereinafter simply referred to as "intersections") of the weft yarns 31 in the front surface side ground weave 10, and is a direction of twill lines in which the centers 31a of the intersections are connected to each other as shown in fig. 3 in a twill weave. The "twist direction" is a direction along the direction of the single yarn constituting the twisted first warp yarn 11 in a plan view as shown in fig. 1 (c). The twist direction and the twill grain direction are aligned, and both the twist direction and the twill grain direction are inclined to the same side with respect to the warp direction of the front side foundation 10. That is, when the first warp yarn 11 is twisted in the Z direction when the twill grain direction is upward to the right, and when the first warp yarn 11 is twisted in the S direction when the twill grain direction is upward to the left, the twist direction coincides with the twill grain direction. When the twist direction of the first warp yarns 11 coincides with the twill grain direction expressed by the front-side base structure 10, a force in the twist rebound direction acts on the first warp yarns 11 during weaving, and the twist of the first warp yarns 11 slightly rebounds in the resulting grass-repellent sheet 1, so that the thickness in appearance increases and gaps are less likely to be generated between adjacent first warp yarns 11. As a result, in the grass-repellent sheet 1, the gaps between the adjacent first warp yarns 11 are filled, and the light-shielding property is improved. In addition, when the weave of the front side ground weave 10 is a satin weave, particularly a satin weave of 7 or more, since the distance of the crowning between the adjacent first warp yarns 11 in the front side ground weave 10 becomes long, the gap between them can be filled up, and the light-shielding property can be more effectively improved.

The number of twists of the first warp yarn 11 is preferably 300 to 500T/m. The twist factor of the first warp yarn 11 is preferably 0.3 to 4, and more preferably 0.9 to 2.4. By setting the twist factor to 0.3 to 4, the twist of the first warp yarns 11 is appropriately rebounded during weaving, so that the gap between the adjacent first warp yarns 11 is more easily filled, and the light-shielding property can be further improved. If the twist factor is less than 0.3, the gap between the first warp yarns 11 cannot be completely filled with the springback even if the twist of the first warp yarns 11 is twisted, and if the twist factor exceeds 4, the twist of the first warp yarns 11 is fixed and is not easily rebounded during weaving, so that there is a possibility that the light-shielding property cannot be sufficiently improved.

In order to maintain high light-shielding properties of the grass-repellent sheet 1, it is preferable that the twist direction of the first warp yarns 11 in the front-side base structure 10 is aligned with the direction of the twill formed by the first warp yarns 11 and the weft yarns 31, and the deviation between both directions is within a certain range. Therefore, in the present invention, the difference (%) between the twill grain angle α and the twill angle β expressed by the following equation (1) is used as a parameter indicating the degree of deviation between the twist direction and the twill grain direction.

The rate of difference (%) ═ α (α - β)/α | × 100 · (1)

As shown in fig. 1 (b), the twill grain angle α is represented by an angle formed by the warp direction and the twill grain direction of the front side base weave 10. As shown in fig. 1 (c), the twist angle β is represented by an angle formed by the warp direction of the front side foundation weave 10 and the twist direction of the first warp 11. The twill grain angle α is positive when the twill grain direction is inclined to the right with respect to the warp direction of the front side base weave 10, and is negative when the twill grain direction is inclined to the left. Similarly, the twist angle β is positive when the twist direction is inclined rightward with respect to the warp direction of the front side ground weave 10, and is negative when the twist direction is inclined leftward. The grass-control sheet 1 preferably satisfies the following equation (2):

|(α-β)/α|×100≤70···(2)

more preferably, the following equation (3) is satisfied:

|(α-β)/α|×100≤60···(3)

by satisfying the above equation (2), when the twist of the first warp yarn 11 rebounds during weaving, the gap between the adjacent first warp yarns 11 in the front-side ground weave 10 is reliably filled, and the light-shielding property of the grass-repellent sheet 1 is further improved. If equation (2) is not satisfied, there is a limit to the improvement of the light-shielding property when the twist of the first warp yarn 11 rebounds during weaving.

The weft yarn 31 is composed of a yarn including a black spun dyed yarn. Since the weft yarn 31 contains a black spun dyed yarn as in the case of the first warp yarn 11, the color tone of the front side ground weave 10 is uniformly blackened, and thus the light-shielding property of the grass-preventive sheet 1 is improved, and the blooming of plants under the sheet can be suppressed. The type of the weft yarn 31 is not particularly limited, and is preferably a non-shrinkable yarn, and more preferably a heat-set yarn. Here, "non-contractible" means a contraction rate of 5% or less, preferably 3% or less. By making the weft yarns 31 non-shrinkable, the grass-protection sheet 1 can be inhibited from shrinking over time, and therefore workability can be improved. When a heat-set yarn is used for the weft yarn 31, heat-setting is preferably performed at 120 to 130 ℃. By performing heat setting under the above-described conditions, appropriate non-shrinkability can be imparted. As the fiber material of the weft yarn 31, synthetic fibers such as polyester fibers, polyamide fibers, and polyolefin fibers are preferably used. By using these synthetic fibers, excellent strength and weather resistance can be obtained. The total fineness of the weft yarns 31 is preferably 77 to 330dtex, and particularly preferably equal to or more than the total fineness of the first warp yarns 11. If the total fineness of the weft yarns 31 is equal to or greater than the total fineness of the first warp yarns 11, the arching of the first warp yarns 11 of the front-side foundation structure 10 becomes long, and therefore the gaps between adjacent first warp yarns 11 are filled, and the light-shielding property is more effectively improved. When multifilament yarn is used for the weft yarn 31, the single yarn fineness of the weft yarn 31 is preferably 1.0 to 5.0 dtex. If the total fineness and the single yarn fineness of the weft yarns 31 are in the above ranges, the grass-repellent sheet 1 has good flexibility and workability in construction can be improved. When the total fineness of the weft yarns 31 is less than 77dtex, or when the single yarn fineness of the weft yarns 31 is less than 1.0dtex, the strength of the grass-protection sheet 1 may be poor. In addition, when the total fineness of the weft yarns 31 exceeds 330dtex, or when the single yarn fineness of the weft yarns 31 exceeds 5.0dtex, the flexibility of the grass-protection sheet 1 may be impaired.

< backside substructure >

Referring to fig. 1 (a), it can be seen that the back side ground weave 20 shown in the even numbered columns in the weave diagram of fig. 2 is woven using the second warp yarns 21 and the weft yarns 31. The weave of the back-side base weave 20 is preferably a twill weave or a satin weave. The warp density of the back-side ground weave 20 is preferably 100 to 200 yarns/2.54 cm. The weft density is preferably 50-150 pieces/2.54 cm. If the warp density and the weft density are within this range, the back-side foundation weave 20 has a dense structure, and light transmission between the second warp 21 and the weft 31 can be suppressed. When the warp density is less than 100 threads/2.54 cm or the weft density is less than 50 threads/2.54 cm, the light transmission between the yarns may not be suppressed. In addition, when the warp density exceeds 200 pieces/2.54 cm, or when the weft density exceeds 150 pieces/2.54 cm, the flexibility of the grass-control sheet 1 may be impaired.

The type of the second warp yarn 21 is not particularly limited, and is preferably a yarn that suppresses light transmittance, such as a black-spun dyed yarn, a full-dull yarn, or a half-dull yarn. As the fiber material of the second warp yarns 21, synthetic fibers such as polyester fibers, polyamide fibers, and polyolefin fibers are preferably used. By using these synthetic fibers, excellent strength and weather resistance can be obtained. These fiber materials may be the same type of fiber materials used for the first warp yarn 11, the second warp yarn 21, and the weft yarn 31, or may be different fiber materials. The total fineness of the second warp yarns 21 is preferably 77 to 330dtex, and when a multifilament yarn is used for the second warp yarns 21, the single yarn fineness of the second warp yarns 21 is preferably 1.0 to 5.0 dtex. If the total fineness and the single yarn fineness of the second warp yarns 21 are within the above ranges, the grass-control sheet 1 is excellent in productivity and flexibility, and workability can be improved. When the total fineness of the second warp yarns 21 is less than 77dtex, or when the single yarn fineness of the second warp yarns 21 is less than 1.0dtex, the strength of the grass-protection sheet 1 may be poor. In addition, when the total fineness of the second warp yarns 21 exceeds 330dtex, or when the single yarn fineness of the second warp yarns 21 exceeds 5.0dtex, the flexibility of the grass-protection sheet 1 may be impaired.

Further, in the grass-repellent sheet 1, in the back-side ground weave 20, as in the front-side ground weave 10, twisted yarns in which single yarns include black spun dyed yarns are used as the second warp yarns 21, and the twist direction of the second warp yarns 21 may be configured to coincide with the twill grain direction expressed in the back-side ground weave 20. In this configuration, since a gap is less likely to be formed between the adjacent second warp yarns 21, the light-shielding property of the grass-protection sheet 1 can be further improved. When the twist direction of the second warp yarns 21 is aligned with the twill grain direction expressed in the back-side base weave 20, the grass-control sheet 1 is preferably woven so that the twill grain angle α formed by the warp direction of the back-side base weave 20 and the twill grain direction and the twist angle β of the second warp yarns 21 satisfy the above equation (2), and more preferably so that the above equation (3) is satisfied. By satisfying the above equation (2), when the twist of the second warp yarns 21 rebounds during weaving, the gap between the adjacent second warp yarns 21 in the back-side ground weave 20 is reliably filled, and the light-shielding property of the grass-repellent sheet 1 can be further improved. In order to further effectively improve the light-shielding property by filling the gap between the adjacent second warp yarns 21, the twist factor of the second warp yarns 21 is preferably 0.3 to 4, and more preferably 0.9 to 2.4, similarly to the first warp yarns 11. The weave of the back-side ground weave 20 is preferably a satin weave, and more preferably a satin weave of 7 or more.

In the back-side ground weave 20, when the twist direction of the second warp yarns 21 is configured to coincide with the twill grain direction expressed in the back-side ground weave 20, the total fineness of the weft yarns 31 is preferably equal to or greater than the total fineness of the second warp yarns 21. If the total fineness of the weft yarns 31 is equal to or greater than the total fineness of the second warp yarns 21, the arching of the second warp yarns 21 of the back-side foundation structure 20 becomes long, and therefore the gaps between adjacent second warp yarns 21 are filled, and the light-shielding property is more effectively improved.

The fibers may contain a weather resistant agent in the first warp yarn 11, the second warp yarn 21, and the weft yarn 31. Examples of the weather-resistant agent include ultraviolet absorbers such as benzotriazoles and benzophenones. In addition, the weather resistant agent may contain a flame retardant, a herbicide, a fungicide, an insect repellent, and the like.

The grass-repellent sheet 1 is preferably provided with a polymer resin on one side or both sides. Since the intersecting portions of the yarns constituting the woven fabric are fixed to some extent by the polymer resin, the penetration of the sprout tips of the thatch or cedar can be reliably suppressed, and the light-shielding property of the grass-shielding sheet 1 can be maintained without the warp and weft being displaced even if the sprout tips of the thatch or cedar touch the grass-shielding sheet 1. The amount of the polymer resin is preferably 5 to 20 wt% based on the weight of the fabric. If the amount of the polymer resin added is within this range, the crossing portion can be fixed relatively reliably, and the base yarn is sufficiently covered with the polymer resin, so that the penetration resistance of the grass-control sheet 1 to plants is improved. In addition, the polymer resin does not hinder the flexibility of the grass-preventive sheet 1. If the amount of the polymer resin added is less than 5 wt%, penetration resistance to plants may be insufficient. If the amount of the polymer resin added exceeds 20 wt%, the flexibility and water permeability of the grass-control sheet 1 may be impaired. Examples of the polymer resin for imparting texture to the fabric may include polyester resins, acrylic resins, vinyl acetate resins, and the like. Among them, polyester resins are preferably used in terms of durability and flame retardancy, and particularly preferably polyester resins having a pencil hardness of 2H to 6H as measured in accordance with JIS K5600-5-4, and further preferably polyester resins having a glass transition temperature of 45 to 75 ℃. Within this range, the yarn constituting the texture of the woven fabric can be reliably fixed without impairing the flexibility of the grass-repellent sheet 1, and penetration resistance can be improved.

Examples of the method of applying the polymer resin include an immersion method, a spraying method, a coating method, and a gravure printing method. Among them, the impregnation method is preferable in that the base yarn can be uniformly covered with the polymer resin. The polymer resin may contain an antioxidant, a light stabilizer, an ultraviolet absorber, a weather resistant agent, a lubricant, a pigment, a filler, and other additives.

< characteristics of grass-preventive sheet >

[ 1] light-shielding rate

The light-shielding rate of the grass-repellent sheet 1 measured by adjusting the light source so that the illuminance before mounting the test piece is 100000 lux is preferably 99.99% or more according to JIS L1055A (test method for light-shielding property of curtain). If the light-shielding rate is 99.99% or more, the flourishing of plants on the ground on which the grass-control sheet 1 is applied can be substantially completely suppressed.

[ 2 ] coverage factor

When the warp density obtained by combining the first warp 11 and the second warp 21 is A (root/2.54 cm), the weft density is B (root/2.54 cm), and the average value of the total fineness of the first warp 11 and the second warp 21 is D_A(dtex) total fineness of weft yarn 31 is D_BIn the case of (dtex), the Coverage Factor (CF) calculated by the following equation (4) is preferably 4000 or more.

CF＝(A×D_A ^1/2)+(B×D_B ^1/2)···(4)

If the Cover Factor (CF) is 4000 or more, the grass-repellent sheet 1 is a high-density woven fabric, and light can be prevented from passing between the single yarns constituting the warp and the weft, thereby further improving the light-shielding property.

[ 3 ] Water Permeability coefficient

The grass-control sheet 1 preferably has a water permeability coefficient of 1.0X 10 measured in accordance with JIS A1218 (soil Water permeability test method)^-3cm/sec or more. As long as the water permeability coefficient is 1.0X 10^-3cm/sec or more, water such as rainwater can quickly permeate therethrough and penetrate into the ground, and therefore, the soil on which the grass-preventive sheet 1 is applied can be prevented from drying.

< method for producing grass-preventive sheet >

The grass-repellent sheet 1 of the present invention is manufactured by weaving weft yarns 31 between a front-side ground weave 10 and a back-side ground weave 20 according to a weave pattern shown in fig. 2, for example, so that the grass-repellent sheet 1 has a twill weave or a satin weave in which the front-side ground weave 10 including first warp yarns 11 and the back-side ground weave 20 including second warp yarns 21 are connected by the weft yarns 31 to form a warp double weave. At this time, a twisted yarn including a black spun dyed yarn is used as the base yarn of the first warp yarn 11, and the twist direction of the first warp yarn 11 is selected so as to match the twill grain direction expressed in the front side ground weave 10.

The base yarn of the weft yarn 31 is a yarn containing a black spun dyed yarn, but is preferably heat-set at 120 to 130 ℃ before weaving. By performing heat setting under the above-described conditions, appropriate non-shrinkability can be imparted, and therefore, the shrinkage of the woven grass-repellent sheet 1 with time can be suppressed.

The grass-control sheet 1 of the present invention woven as described above has the following structure: by having a twill weave or satin weave including the front side foundation weave 10, the back side foundation weave 20, and the weft yarns 31 formed by connecting the front side foundation weave 10 and the back side foundation weave 20 to form a double weave, no slippage occurs between the front side foundation weave 10 and the back side foundation weave 20, and therefore breakage is less likely to occur. The front side ground weave 10, which is composed of the first warp yarn 11, which is a twisted yarn including a black spun-dyed yarn, and the weft yarn 31, which is a yarn including a black spun-dyed yarn, is black in color tone, and thus has high light-shielding properties. Further, by weaving in such a manner that the twist direction of the first warp yarns 11 coincides with the twill grain direction expressed in the front-side ground weave 10, a force in the twist rebound direction acts on the first warp yarns 11, and the twist slightly rebounds in the grass-repellent sheet 1 that is woven, so that the apparent thickness of the first warp yarns 11 increases, the gaps between adjacent first warp yarns 11 are filled, and the light-shielding property can be further improved.

Examples

In order to confirm the light-shielding property of the grass-guard sheet of the present invention, a grass-guard sheet having the structure of the present invention was produced (examples 1 to 3). For comparison, grass-control sheets different from the present invention were produced (comparative examples 1 and 2).

< example 1>

A multifilament yarn (Z-direction twist, number of twists: 400T/m, heat-set conditions: 85 ℃ C. times.40 minutes) having a total fineness of 84dtex/36f, using a black spun dyed yarn made of PET as a single yarn, was used as a first warp yarn, and a multifilament yarn (S-direction twist, number of twists: 400T/m, heat-set conditions: 85 ℃ C. times.40 minutes) having a total fineness of 84dtex/36f, using a semi-dull yarn made of PET as a single yarn, was used as a second warp yarn. The twist yarn factor of the first warp yarn and the second warp yarn is 1.2. As the weft yarn, a multifilament yarn (heat-set condition: 130 ℃ C. times.40 minutes) having a total fineness of 167dtex/36f, in which a black spun-dyed yarn made of PET was used as a single yarn, was used. The first warp, the second warp, and the weft were woven in a double 7-ply satin weave in the twill grain direction of the surface side ground weave so that the warp density obtained by combining the first warp and the second warp was 309 pieces/2.54 cm and the weft density was 100 pieces/2.54 cm, to obtain the grass-repellent sheet of example 1.

The grass-repellent sheet of example 1 had a twill grain angle α of 41 ° on average, a twist angle β of 17 ° on average, and an angular difference between the twill grain angle α and the twist angle β of 17 to 32 °, and the difference ratio calculated by the above equation (1) was 58.5 (%), satisfying the above equation (2). The Cover Factor (CF) was 4124.

< example 2>

An anti-grass sheet of example 2 was woven in the same manner as in example 1, except that the twist of the first warp was S-direction twist, the twist of the second warp was Z-direction twist, and the weave structure was double 7 satin weave in the twill grain direction of the front side ground weave.

The twill grain angle α of the grass-repellent sheet of example 2 is-41 ° on average, the twist angle β is-17 ° on average, the angular difference between the twill grain angle α and the twist angle β is 17 to 32 °, and the difference ratio is 58.5 (%), and satisfies the above equation (2). The Cover Factor (CF) was 4124.

< example 3>

An grass-repellent sheet of example 3 was produced in the same manner as in example 1, except that the combined first warp and second warp was woven so that the warp density was 283 yarns/2.54 cm and the weft density was 106 yarns/2.54 cm.

The grass-repellent sheet of example 3 had a twill grain angle α of 36 ° on average, a twist angle β of 17 ° on average, an angle difference between the twill grain angle α and the twist angle β of 11 to 28 °, and a difference rate of 52.5 (%), and satisfied the above equation (2). The Cover Factor (CF) was 3964.

< comparative example 1>

An grass-repellent sheet of comparative example 1 was woven in the same manner as in example 1, except that the weave pattern was a double 7 satin weave pattern in which the twill grain direction of the surface side ground weave was an upward-facing warp.

The grass-repellent sheet of comparative example 1 had a twill grain angle α of-38 ° on average, a twist angle β of 13 ° on average, an angle difference between the twill grain angle α and the twist angle β of 46 to 54 °, and a difference rate of 134.2 (%), which did not satisfy the above formula (2). The Cover Factor (CF) was 4124.

< comparative example 2>

An grass-repellent sheet of comparative example 2 was produced in the same manner as in example 1, except that the twist of the first warp was an S-direction twist and the twist of the second warp was a Z-direction twist.

The grass-repellent sheet of comparative example 2 had a twill grain angle α of 38 ° on average, a twist angle β of-13 ° on average, an angle difference between the twill grain angle α and the twist angle β of 46 to 54 °, and a difference rate of 134.2 (%), which did not satisfy the above formula (2). The Cover Factor (CF) was 4124.

[ measurement of light-blocking Rate ]

The grass-control sheets of examples 1 to 3 and comparative examples 1 and 2 were measured for light-shielding rate by adjusting the light source so that the illuminance before mounting the test piece was 100000 lux according to JIS L1055A (test method for light-shielding property of a curtain).

Table 1 shows the structures of the grass-protective sheets of examples 1 to 3 and comparative examples 1 and 2, and the measurement results of the light-shielding property test.

[ Table 1]

The grass-control sheets of examples 1 to 3 all had a light-blocking ratio of 99.99%. Therefore, if the grass-control sheet of examples 1 to 3 is used to cover the ground, the blooming of plants can be substantially completely suppressed.

On the other hand, the grass-preventive sheet of comparative example 1 had a light-blocking ratio of 99.98%, and the grass-preventive sheet of comparative example 2 had a light-blocking ratio of 99.97%. When the grass-control sheets of comparative examples 1 and 2 were used to cover the ground, the grass-control effect was not reliable, and some plants were likely to flourish.

Although the grass-repellent sheet of example 1 uses the same yarn as that used in the grass-repellent sheet of comparative example 1, the weave pattern is the same as the warp yarn fly number or the like, except that the twill grain direction of the front side ground weave is reversed, and the shading rate is different. To investigate the cause, the surface-side base structures were photographed under magnification with a microscope and observed in detail. Fig. 4 (a) is a microscope image obtained by imaging the surface side ground structure in the grass-prevention sheet of example 1, and fig. 4 (b) is a microscope image obtained by imaging the surface side ground structure in the grass-prevention sheet of comparative example 1.

In the image of fig. 4 (a) obtained by imaging the front-side ground structure of the grass-repellent sheet of example 1, the adjacent first warp yarns are closely attached to each other with substantially no gaps therebetween. On the other hand, in the image obtained by imaging the front-side ground structure of the grass-guard sheet of comparative example 1, as indicated by a white frame in fig. 4 (b), a gap is formed between the adjacent first warp yarns and between the adjacent first warp yarns. The presence or absence of the gap between the adjacent first warp yarns 11 due to such a difference in the state of crowning is considered to be a factor that affects the light-shielding rate of the grass protection sheet.

< reference example >

In the above examples, the heat setting of the weft yarn was performed at 130 ℃, but the influence of the shrinkage with time due to the decrease in the heat setting temperature was also examined. As a reference example, an anti-grass sheet was produced which was woven in the same manner as in example 1, except that the heat-setting conditions of the weft were set to 85℃ × 40 minutes. The grass-repellent sheet of the reference example was subjected to the same conditions as those of the grass-repellent sheet of example 1, except that the weft yarns were heat-set at 85 ℃. As a result of comparing the shrinkability with time of the grass-preventive sheet of example 1 and the grass-preventive sheet of reference example, the dimensional change rate in the weft direction was smaller in the grass-preventive sheet of example 1 (heat-set: 130 ℃ C.) than in the grass-preventive sheet of reference example (heat-set: 85 ℃ C.). Further, the same examination was made on the case where the heat-setting temperature was 120 ℃ and, as a result, the dimensional change rate in the weft direction was smaller than that of the grass-preventive sheet of the reference example (heat-setting: 85 ℃). Therefore, it is found that if the weft is heat-set at least 120 ℃, the shrinkage of the grass-preventive sheet with time can be suppressed, and good workability can be achieved.

Industrial applicability

The grass-control sheet of the present invention is used for suppressing the proliferation of unnecessary plants, and is suitable for use in buildings such as houses, the surroundings of trees on streets, agricultural lands such as orchards and vegetable gardens, construction sites, large-sized solar power plants, railways, roads, and the like.

Description of reference numerals:

1 grass-proof sheet

10 surface side base structure

11 first warp yarn

20 back side ground texture

21 second warp yarn

31 weft yarn

Center of intersection 31a

Angle of alpha twill line

Beta lay angle

Claims

1. A grass-control sheet having a twill weave or a satin weave including a front side ground weave including first warp yarns, a back side ground weave including second warp yarns, and weft yarns connecting the front side ground weave and the back side ground weave to form a warp double weave, wherein,

the grass-prevention sheet is configured as follows:

the first warp yarn is a twisted yarn comprising a black spun dyed yarn,

the weft yarns are yarns comprising black spun dyed yarns,

2. The grass protection sheet according to claim 1,

in the front side base weave, when a twill line angle formed by a line connecting crossing points where the weft yarns are exposed and a warp yarn direction is defined as α, and a twist angle of the first warp yarn of the front side base weave is defined as β, the following equation (1) is satisfied:

|(α-β)/α|×100≤70…(1)。

3. the grass-protective sheet according to claim 1 or 2,

the yarn twisting coefficient of the first warp yarn is 0.3-4.

4. The grass-protective sheet according to claim 1 or 2,

the weft yarns are non-shrinkable yarns.

5. The grass-protective sheet according to claim 1 or 2,

the grass-prevention sheet has a cover factor of 4000 or more.

6. The grass-protective sheet according to claim 1 or 2,

the weft yarn is composed of a yarn having the same thickness as or greater than the first warp yarn.

7. The grass-protective sheet according to claim 1 or 2,

the first warp yarn, the second warp yarn, and the weft yarn are each at least one selected from the group consisting of a polyester yarn, a polyolefin yarn, and a polyamide yarn.

8. The grass-protective sheet according to claim 1 or 2,

the surface side base weave is composed of a satin weave.

9. A method for producing a grass-repellent sheet having a twill weave or satin weave formed by connecting a front-side ground weave including first warp yarns and a back-side ground weave including second warp yarns with weft yarns to form a warp double weave,

in the method of manufacturing the grass-preventive sheet,

using a twisted yarn comprising a black spun dyed yarn as the first warp yarn,

using a yarn comprising a black spun dyed yarn as the weft yarn,