JP2003089942A - Net-formed product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a net-formed product free from the troubles of the shift of mesh yarns and the fray of the edge, having sufficient strength and durable to repeated extension by firmly bonding the crossing points of the wefts and warps with heat. SOLUTION: The net-formed product is produced by using a triple layer flat yarn as one of the warp and weft and a sheath-core conjugate monofilament yarn as the other yarn and heat-bonding the crossing points of the warps and the wefts. The triple layer flat yarn has a triple layer structure composed of propylene copolymer layers composed mainly of propylene and copolymerized with an α-olefin as both surface layers and a polypropylene layer as the core layer. The sheath-core conjugate monofilament yarn has a sheath-core structure composed of a propylene copolymer composed mainly of propylene and copolymerized with an α-olefin as the sheath component and a polypropylene as the core component. The yarns are woven and the crossing points of the warps and wefts are integrated by heat bonding.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a net-shaped product obtained by weaving a three-layer flat yarn and a composite monofilament yarn, and heat-bonding the intersecting portions thereof.

[0002]

2. Description of the Related Art Conventionally, a net-like material composed of a flat yarn or a monofilament yarn has been widely used in the fields of agriculture such as a light-shielding net, a gauze cloth, an insect net, and the field of construction and civil engineering. As a net-like material, a net-like material in which a flat yarn or a monofilament yarn made of a single material for both warp and weft is net-woven is generally used. However, in the net-like material having this structure, since the intersections of the warp threads and the weft threads are not adhered, when the net-like material having a wide mesh is used, misalignment is likely to occur, and the net-like material is produced in the net manufacturing process. When slitting is performed, there is a problem that the cut end portion is loosened.

As a method for preventing such misalignment and loosening, a flat yarn having a three-layer structure and a composite monofilament yarn are used for both warp and weft yarns in Japanese Unexamined Patent Publication No. 1-321947, and the crossing portion of the warp and weft yarns is heated. A bonded net is disclosed. This net-like material has no misalignment or loosening of the edges, has sufficient strength, and has excellent spreadability. However, the net-shaped material, using the low-density polyethylene as the thermoplastic resin that constitutes both outer layers of the three-layer flat yarn and the sheath component of the sheath-core type composite monofilament yarn, and the middle-core layer of the three-layer flat yarn,
Since high-density polyethylene is used as the thermoplastic resin that constitutes the core component of the sheath-core type composite monofilament, the adhesive portion between the flat yarn and the composite monofilament yarn peels off when the spread book is repeatedly used. There is a problem that this causes eye misalignment and further reduces durability.

[0004]

DISCLOSURE OF THE INVENTION The object of the present invention is to firmly bond the intersections of both warp and weft yarns by heat, to prevent misalignment and loosening of the ends, and to have sufficient strength for repeated book spreading. It is to provide a net-like material that can withstand.

[0005]

As a result of intensive studies to solve the above problems, the present inventor constructed both outer layers of a three-layer flat yarn and a sheath component of a sheath-core type composite monofilament yarn. The thermoplastic resin to be used, a propylene copolymer consisting of propylene containing propylene as a main component and an α-olefin, is used, and the heat that forms the core layer of the three-layer flat yarn and the core component of the sheath-core type composite monofilament is used. It was found that the above problems can be solved by using polypropylene as the plastic resin, and the present case was completed based on this finding. That is, the present invention has the following configurations. (1) A net-like material obtained by weaving the three-layer flat yarn as one of the warp and weft yarns and the sheath-core type composite monofilament yarn as the other yarn of the warp and weft yarns and thermally bonding the intersections of the warp yarns and the weft yarns. The three-layer flat yarn is a three-layer structure in which a propylene copolymer layer composed of propylene and a α-olefin containing propylene as a main component is disposed on both outer layers, and a polypropylene layer is disposed on a core layer. The sheath-core type composite monofilament yarn having a structure has a sheath component in which a propylene copolymer composed of propylene having propylene as a main component and α-olefin is disposed in the sheath component, and polypropylene in the core component. A net-like material having a core structure, in which both are woven, and the intersections of the warp threads and the weft threads are heat-bonded and integrated. (2) The net-like article according to item (1), wherein the propylene copolymer composed of propylene containing propylene as a main component and an α-olefin is an ethylene / propylene copolymer. (3) The net-like material according to the above item (1), wherein the propylene copolymer mainly composed of propylene and α-olefin is an ethylene / propylene / butene-1 copolymer. .

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is described in detail below.
The net-like material of the present invention is woven with a three-layer flat yarn made of the following thermoplastic resin as one of the warp and weft yarns, and a sheath-core type composite monofilament yarn made of the following thermoplastic resin as the other yarn of the warp and weft yarns, It is a net-like material in which the intersections of the warp threads and the weft threads are heat-bonded and integrated.

In the three-layer flat yarn used in the present invention, a layer of a propylene copolymer consisting of propylene containing propylene as a main component and α-olefin as a thermoplastic resin is arranged on both outer layers, and a core layer is formed. It has a three-layer structure in which a polypropylene layer is arranged. Incidentally, the propylene copolymer composed of propylene containing propylene as a main component and an α-olefin refers to a propylene copolymer composed of propylene and an α-olefin in which the most component in the propylene copolymer is propylene. Say.

The sheath-core type composite monofilament yarn used in the present invention has a sheath component as a thermoplastic resin,
It has a sheath-core structure in which a propylene copolymer containing propylene as a main component and α-olefin is arranged and polypropylene is arranged as a core component.

The polypropylene used as the core component of the core layer of the three-layer flat yarn and the sheath-core type composite monofilament yarn of the present invention is crystalline polypropylene, which is a propylene homopolymer or a small amount of propylene. Is a copolymer with 1% by weight or less of α-olefin. As such polypropylene, isotactic polypropylene polymerized using a known Ziegler-Natta catalyst, isotactic polypropylene polymerized using a metallocene catalyst, or syndiotactic polypropylene can be used. Moreover, you may mix and use these multiple types in the range which does not prevent the effect of this invention. The MFR (melt flow rate) of polypropylene used for the sheath-core type composite monofilament yarn is 0.
In the range of 1 to 20 g / 10 minutes, the spinnability is good,
The tenacity of the obtained composite monofilament yarn is also sufficient, and more preferably 0.1 to 10 g / 10 minutes. When polypropylene having an MFR significantly exceeding 20 g / 10 min is used, the spinnability of the composite monofilament yarn tends to deteriorate. The molecular weight distribution (Mw / Mn) of polypropylene is not particularly limited, but polypropylene having a molecular weight distribution of 3 or less is preferable in consideration of spinnability. Further, if the MFR (melt flow rate) of polypropylene used for the three-layer flat yarn is in the range of 0.1 to 20 g / 10 min, the film-forming property is good, and the strength of the obtained three-layer flat yarn is sufficient. Is preferable, and more preferably 0.1 to 10 g / 1.
A range of 0 minutes is good. When polypropylene having an MFR significantly exceeding 20 g / 10 min is used, the film forming property of the three-layer flat yarn tends to be deteriorated.

Further, as a propylene copolymer composed of propylene containing propylene as a main component and α-olefin, which is used as the outer layer of the three-layer flat yarn of the present invention and the sheath component of the sheath-core type composite monofilament yarn,
Examples thereof include binary or random copolymers of propylene containing propylene as a main component and monomers other than propylene, and mixtures of two or more of these. The monomer other than propylene is not particularly limited,
Ethylene, 1-butene, 1-pentene, 1-hexene,
Examples include α-olefins having 2 to 12 carbon atoms such as 1-octene. These may be used alone or in combination of two or more. Specifically, an olefin-based terpolymer containing propylene as a main component or an olefin-based terpolymer containing propylene as a main component can be mentioned. The olefin-based binary copolymer is ethylene / ethylene having an ethylene content of 1 to 15% by weight and a propylene content of 85 to 99% by weight.
A propylene copolymer, a propylene / 1-butene copolymer having a propylene content of 50 to 99% by weight and a 1-butene content of 1 to 50% by weight can be used. As the olefinic terpolymer, ethylene / propylene / butene-having an ethylene content of 1 to 10% by weight, a propylene content of 84 to 98% by weight, and a 1-butene content of 1 to 15% by weight.
1 copolymer available, ethylene content 3-5% by weight, propylene content 92-96% by weight, 1-butene content 1-3.
A weight% of ethylene / propylene / butene-1 copolymer is more preferably utilized. These can be polymerized by using a Ziegler-Natta catalyst or a metallocene catalyst similarly to the above polypropylene, and it is preferable that the MFR and the molecular weight distribution are also in the same range.

In the present invention, polypropylene used as the core component of the three-layer flat yarn of the present invention and the sheath-core type composite monofilament yarn, the outer layer of the three-layer flat yarn of the present invention, and the sheath, if necessary. Various additives generally used in the propylene copolymer consisting of propylene and α-olefin containing propylene as the main component used as the sheath component of the core-type composite monofilament yarn, for example, an antioxidant, a light stabilizer, UV absorber, antistatic agent, neutralizing agent, lubricant, antiblocking agent,
A flame retardant, a pigment (carbon black, etc.), an antibacterial agent, etc. are added and compounded, and the obtained compound is extruded by an extruder to form a film or filament.

In particular, in order to improve the light-shielding performance of the net-like material, it is sufficient to reduce the solar light transmittance of the flat yarn and the composite monofilament yarn forming the net-like material. It is good to add.
Above all, the addition of a pigment having a large hiding power is particularly preferable because it has a high effect of preventing transmission. For example, it is preferable to use a flat yarn and a composite monofilament yarn to which carbon black is added as a pigment to form a net, and use this net as a light-shielding net because the light-shielding net can reduce the transmission of sunlight.

In the present invention, the above additives can be added to the thermoplastic resin constituting the net-like material of the present invention in the form of compound or masterbatch. For example, the additive and the thermoplastic resin powder are uniformly mixed with a publicly known and officially used tumbler mixer, Henschel mixer (trade name), super mixer, ribbon blender, Banbury mixer, etc., and then a mixing roll, an extruder, etc. It is possible to make pellets which are melted and kneaded by heating using, and further cut into granules. Use the pellets as a compound or masterbatch.

In the present invention, examples of a method for molding a thermoplastic resin into a three-layer film include an extrusion molding method such as a T-die method and an inflation method, a calendering method, and the like. An extrusion method that is easy to produce is preferable. When the extrusion molding method is used, for example, the thermoplastic resin used for each of the outer layer and the core layer is melted, the molten polymer is supplied to one die, and each thermoplastic resin layer is fused inside the die. Film formation,
The obtained three-layer film is slit into a certain width and stretched to give further strength. Further, it can also be produced by stretching in the state of the three-layer film and then slitting into a narrow width. Further, the stretching is uniaxial stretching in the machine direction (MD), and as a heating method of the film or the like at the time of stretching, a method of passing hot air or hot water or a method of contacting with a hot plate or a heating roll can be used. , Either may be used. The draw ratio is preferably 5 to 9 times.

In the present invention, the fineness of the three-layer flat yarn is 200 to 2000 dtex, preferably 300 to 1
It is 000 dtex. The flat yarn has a fineness of 2
When it is less than 00 dtex, the strength of the flat yarn is low, and when it exceeds 2000 dtex, the rigidity becomes too high, which makes it difficult to knit or weave. The flat yarn preferably has a width of 1 to 10 mm and a thickness of 30 to 300 μm.
m is preferred. If the width of the flat yarn is less than 1 mm, the strength of the flat yarn is too low, and if it exceeds 10 mm, knitting or weaving becomes difficult. Further, if the thickness of the tape yarn is less than 30 μm, the film forming property becomes poor, and if it exceeds 300 μm, it becomes difficult to knit or weave. The single layer thickness of the outer layer of the three-layer flat yarn is preferably in the range of 5 to 100 μm,
The range of 10 to 100 μm is more preferable.

In the present invention, as the method for molding the thermoplastic resin into the sheath-core type composite monofilament yarn, an ordinary composite spinning method can be used. In this case, for example, by melting the thermoplastic resin used for the sheath component and the core component,
The molten polymer is supplied to one die, drawn out as a sheath-core type composite shape by the composite mouthpiece part, and solidified by cooling with water to form a composite monofilament. By stretching this after heating, it is possible to impart strength to the composite monofilament yarn.

The structure of the net-like material of the present invention will be described in detail with reference to FIG. The three-layer flat yarn (1) used in the present invention has a structure having outer layers (1a) on the front and back of the core layer (1b). The composite monofilament yarn (2) used in the present invention has a structure of a composite fiber composed of a sheath component (2a) and a core component (2b). The net-like material of the present invention is woven using the three-layer flat yarn (1) for one of the warp and weft yarns and the composite monofilament yarn (2) for the other, which is lower than the melting point of polypropylene and contains propylene. Propylene and α as main components
A net-like material in which a heat-bonded intersection (3) is formed by heat treatment at a temperature higher than the melting point of a propylene copolymer containing olefin. Here, in the crossing portion (3), the outer layer (1a) of the three-layer flat yarn (1) and the sheath component (2a) of the composite monofilament yarn are softened / melted and bonded. If this bonded portion does not peel off, there will be no misalignment or loosening. At this time, the fineness of the composite monofilament yarn (2) used for the warp and weft yarns, the thickness and width of the three-layer flat yarn (1), and the number of threads of each can be arbitrarily set according to the application. It is also possible to mix the three-layer flat yarn (1) and the composite monofilament yarn (2) in both the warp and weft yarns to form a net-like material.

The net-like material of the present invention is used in the fields of agriculture such as light-shielding nets, ginseng nets, wind-proof nets, sand-proof nets, insect-proof nets, bird-proof nets, vegetable packing bags, construction nets, base materials for construction sheets, and concrete. Building fields such as curing mats,
It can be suitably used in various fields such as civil engineering fields such as drain materials, daily sundries such as drainage bags, garbage bags and laundry bags, various backing materials, industrial materials such as packing cloths and container bags. Above all, it is particularly preferably used for a light-shielding net or the like for repeatedly carrying out exhibition.

[0019]

EXAMPLES The present invention will be described in detail below with reference to examples. Further, the measuring method used in the present invention will be described. MFR: The melt flow rate of polypropylene or the like is measured according to JIS K 7210-1976 "flow test method for thermoplastics" (condition 14 in Table 1, test temperature 230 ° C, test load 21.18N). MI: JIS K 7210-1976 "The flow test method for thermoplastics" (condition 10 in Table 1, test temperature 190 ° C, test load 21.18N) is used to measure the melt flow rate of polyethylene or the like. Repeated expansion test: A net-like material cut into A4 size is prepared, and the expansion book-winding is repeated 100 times for one net, and the peeling of the adhesive portion of the net is observed.

Example 1 The core layer (1b) had an MFR of 1.8 g / 10 mi.
n, a polypropylene having a melting point of 163 ° C. (propylene homopolymer) is used, and the outer layer (1a) has an MFR of 2.0.
An ethylene / propylene copolymer (ethylene content 3.35% by weight, propylene content 96.65% by weight) having a g / 10 min and a melting point of 142 ° C. was used to extrude a three-layer film by air-cooling type two-layer inflation with three layers. The film is formed, and the three-layer film is slit into a width of 4 mm, and the draw ratio is 7
Double stretched, 385 dtex, strength 5.4 cN / dte
A three-layer flat yarn having x and an elongation of 25% was obtained. Next, as the core component (2b), the MFR was 1.8 g / 10 min,
Using polypropylene (propylene homopolymer) having a melting point of 163 ° C., the sheath component (2a) has an MFR of 2.0 g.
Using an ethylene / propylene copolymer (ethylene content 3.35% by weight, propylene content 96.65% by weight) with a melting point of / 10 min and a melting point of 142 ° C., spinning was performed with a composite spinning machine and stretched 6.5 times with a roll. 550 dtex,
A composite monofilament yarn having a strength of 3.4 cN / dtex and an elongation of 31% was obtained. Using the three-layer flat yarn as the weft and the composite monofilament yarn as the warp, both were plain woven with a loom and further heated to 158 ° C. in a through air processing machine, and the crossing portion of the warp and weft was thermally bonded. A net-like article having the shape shown in FIG. 1 was obtained. When repeated spreading was carried out using this net-like material, it was found that the bonded portion of the net in the hinge portion of the spreader did not peel off and the durability was excellent.

Example 2 As a propylene copolymer, MFR was 5.5 g / 10 m.
in, ethylene / propylene / butene with a melting point of 129 ° C.
1 copolymer (ethylene content 3.65% by weight, butene-1
A net-like material having the shape shown in FIG. 1 was obtained in the same manner as in Example 1 except that the content was 2.65% by weight and the propylene content was 93.70% by weight. When repeated spreading was carried out using this net-like material, it was found that the bonded portion of the net in the hinge portion of the spreader did not peel off and the durability was excellent.

Comparative Example 1 MI as the core layer (1b) was 5.0 g / 10 mi.
n, a high-density polyethylene having a melting point of 132 ° C., a low-density polyethylene having an MI of 8.0 g / 10 min and a melting point of 107 ° C. is used as the outer layer (1a), and three layers are formed by air-cooling inflation of two types and three layers. The film was extruded and formed into a film, the multilayer film was slit into a width of 4 mm, and further stretched at a draw ratio of 6.52 to obtain a three-layer flat yarn having 370 dtex, strength of 4.5 cN / dtex and elongation of 26%. . Next, MI is 5.0 as the core component (2b).
Using a high density polyethylene having a melting point of 132 ° C. for g / 10 min and using a low density polyethylene having an MI (melt index) of 8.0 g / 10 min and a melting point of 107 ° C. as a sheath component (2a), spinning was performed by a composite spinning machine. , Stretched 7 times by roll, 500 dtex, strength 1.9c
A composite monofilament yarn having N / dtex and an elongation of 23% was obtained. Using the above three-layer flat yarn as the weft and the composite monofilament yarn as the warp, both of them were plain woven by a loom, and further this was lapped at 125 ° C by a through air processing machine.
Then, a net-like article having the shape shown in FIG. 1 was obtained, in which the intersections of the warp and weft yarns were heat-bonded. When repeated spreading was performed using this net-like material, it was found that peeling occurred at the adhesive part of the net in the hinge portion of the spread book, and it was found that the durability was poor.

[0023]

INDUSTRIAL APPLICABILITY The net-like article of the present invention is capable of firmly heat-bonding the intersections of both warp and weft yarns, and is
Further, since the misalignment and the loosening of the end portion are unlikely to occur, the net shape can be more favorably maintained. Further, since it has excellent repeatability, it has excellent durability and can be favorably used for a light-shielding net or the like for performing repeated exhibitions.

[Brief description of drawings]

FIG. 1 is a partially enlarged perspective view of a net-like object of the present invention.

[Explanation of symbols]

1 Three-layer flat yarn 1a outer layer 1b Core layer 2 Composite monofilament yarn 2a sheath component 2b core component 3 intersections

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) // D01F 8/06 D01F 8/06 F term (reference) 2B024 AA01 DA03 DB01 DB04 DB07 DD01 2B029 EB03 EB08 EC02 EC06 EC12 EC14 4L041 AA20 AA28 BA02 BA03 BA05 BA09 BA21 BA37 BC20 BD02 BD03 BD14 CA38 CA42 CA43 DD05 DD11 DD24 4L048 AA15 AA28 AA30 AA37 AA44 AA46 AB10 AB28 AC18 BA01 BA02 BA06 CA00 CA01 DA28 DA30 EB05

Claims (3)

[Claims] 1. A net shape in which a three-layer flat yarn is woven as one of the warp and weft yarns and a sheath-core type composite monofilament yarn is woven as the other yarn of the warp and weft yarns, and the intersections of the warp yarns and the weft yarns are heat-bonded. In the three-layer flat yarn, a layer of propylene copolymer composed of propylene containing propylene as a main component and α-olefin is arranged on both outer layers, and a layer of polypropylene is arranged on the center core layer. It has a three-layer structure, the sheath-core type composite monofilament yarn, the sheath component, a propylene copolymer consisting of propylene and α- olefin containing propylene as a main component is arranged,
It has a sheath-core structure in which polypropylene is arranged in the core component, and both are woven, and the intersections of the warp and weft are heat-bonded and integrated, which is a net-like material. 2. The net-like material according to claim 1, wherein the propylene copolymer composed of propylene containing propylene as a main component and an α-olefin is an ethylene / propylene copolymer. 3. The net-like material according to claim 1, wherein the propylene copolymer composed of propylene containing propylene as a main component and an α-olefin is an ethylene / propylene / butene-1 copolymer. .