JP3217766U - Peeling protection net - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a peeling protection net having rigidity while having flexibility that is easy to follow along an underside of an elevated or an inner wall surface of a tunnel.
The peeling protection net is composed of a net. The net base 1 and the knot 2 are formed of a fiber reinforced plastic material having a low melting point polymer as a base and a plurality of high melting point polymer fibers existing in the base. The mass ratio of the low melting point polymer and the high melting point polymer fiber is low melting point polymer: high melting point polymer fiber = 1: 1 to 3. The low melting point polymer is derived from the sheath component of the core-sheath type composite long fiber, and the high melting point polymer fiber is derived from the core component of the core-sheath type composite long fiber. The low melting point polymer is a copolyester, and the high melting point polymer is polyethylene terephthalate. A fabric 4 for connecting the mesh or fixing the structure is sewn on the edge of the mesh.
[Selection] Figure 1

Description

  The present invention relates to a peeling protection net that protects people and automobiles against the fallen objects falling from the structure, in particular, on the underside of an elevated bridge that bridges a bridge, road, or track, etc., and on the inner wall of a cave or tunnel. It relates to a peeling protection net for tensioning.

  Conventionally, a net knitted or netted with synthetic fiber yarn has been used as a peeling protection net. Such a mesh is stretched and used on the lower surface of the elevated, the inner wall surface of the tunnel, or the wall surface of the construction site. However, since the net made of synthetic fiber yarn is flexible, it sometimes hangs down after being stretched on the underside of the elevated. For this reason, it has been proposed to attach a shape-retaining band to a part of the netting to give rigidity to the netting (Patent Document 1). It is described that the shape-retaining band is formed by placing a glass fiber bundle impregnated with a thermosetting resin on a mesh surface and heating and pressing (Patent Document 1, paragraph 0022).

  However, in order to manufacture the peeling protection net described in Patent Document 1, a process of attaching a shape retaining band to the mesh is required, which is complicated. In addition, the rigidity is improved at the portion where the shape retaining band is attached, but the portion where the shape retaining band is not attached is still lacking in rigidity and has a drawback that sagging occurs.

JP 2011-241635 A

  An object of the present invention is to provide a peeling protection net having rigidity while having flexibility that is easy to follow along an underside of an elevated or an inner wall surface of a tunnel.

  The present invention solves the above-mentioned problems by forming a knot and a net leg of a net with a fiber reinforced plastic material in which a specific polymer is used as a base and a specific polymer fiber is dispersed therein. Is. That is, the present invention provides a stripping protection net comprising a net used to be stretched on a structure, wherein the net legs and knots of the net are based on a low melting point polymer, and a plurality of high melting points are formed in the base. It is formed of a fiber reinforced plastic material in which polymer fibers are present, and the mass ratio of the low melting point polymer and the high melting point polymer fiber is low melting point polymer: high melting point polymer fiber = 1: 1 to 3. It is related with the peeling protection net characterized by this.

The net used in the present invention is composed of a net 1 and a knot 2. A part surrounded by the net legs 1 and the nodules 2 is a gap and is called an eye 3. The form of the eye 3 may be a square as shown in FIG. 1 or may be another form such as a rhombus. As shown in FIG. 1, the nodule 2 may be a nodule or a nodule. Since a nodule is likely to have irregularities in the nodule, it is preferably no-nodule. The diameter of the mesh leg 1 is about 2 to 7 mm, and the area of the nodule 2 is about 25 to 80 mm ² . Moreover, the size (mesh) of the eyes 3 is about 5 to 20 mm. When the mesh is less than 5 mm, the mesh 3 is small, and the air permeability tends to deteriorate and the weight of the netting tends to increase. On the other hand, when the mesh exceeds 20 mm, the eyes 3 become too large, and the peeled objects easily fall off.

  The net legs 1 and the knots 2 are formed of a fiber reinforced plastic material having a low melting point polymer as a base and a plurality of high melting point polymer fibers existing in the base. Examples of the combination of the low melting point polymer and the high melting point polymer fiber include a combination of polyolefin and polyethylene terephthalate fiber, a combination of polyamide A and polyamide B fiber, or a combination of copolymerized polyester and polyethylene terephthalate fiber. Here, polyethylene is generally used as the polyolefin which is a low melting point polymer. In addition, as polyamide A, which is a low melting point polymer, a copolymerized polyamide can be generally used. Specifically, the monomers constituting polyamide 6, polyamide 11 or polyamide 12 are copolymerized at an appropriate ratio. What is formed can be adopted. As the polyamide B fiber which is a high melting point polymer fiber, polyamide 6 fiber is generally used. The copolymer polyester, which is a low melting point polymer, is obtained by copolymerizing terephthalic acid and ethylene glycol with other monomers such as 1,4-butanediol, aliphatic lactone, or adipic acid. The difference in melting point between the low-melting polymer and the high-melting polymer is arbitrary, but is generally about 50 to 200 ° C.

  The mass ratio of the low melting point polymer and the high melting point polymer fiber is low melting point polymer: high melting point polymer fiber = 1: 1 to 3. When the mass ratio of the low melting point polymer is lower than this range, it becomes difficult to become a base material. On the other hand, if the mass ratio of the low-melting polymer is higher than this range, the diameter or number of the high-melting polymer fibers becomes small, and the strength of the fiber-reinforced plastic material is lowered. FIG. 2 is a photograph of the cross section of the screen legs 1 observed with a microscope, and is a photograph of using polyethylene 6 as the low-melting polymer and polyethylene terephthalate fiber 7 as the high-melting polymer. In FIG. 2, the whitish portion is polyethylene 6, which is the parent body. In FIG. 2, the blackish portion is a cross section of the polyethylene terephthalate fiber 7.

  The net used in the present invention may be used as it is as a peeling protection net, but generally the net is fixed to the fabric 4 or structure for connecting the nets to the edge of the net with pins or the like. It is preferable to sew the fabric 4 for sewing with the sewing thread 5. As the fabric 4, a knitted fabric or a nonwoven fabric is used. The fabric 4 can be sewn with the sewing thread 5 because the mesh used in the present invention is manufactured using a core-sheath type composite continuous fiber. That is, at the stage before the mesh legs and knots are made of fiber-reinforced plastic material (precursor network of the stage composed of core-sheath type composite continuous fibers), the fabric 4 and the precursor network are overlapped with a sewing machine. This is because it can be sewn. The peeling protection net according to the present invention is mainly used by being stretched on a concrete structure. In other words, it is used by being stretched on the underside of an elevated road such as an expressway or on the inner wall surface of a tunnel, so that the concrete pieces that have deteriorated and fall off do not pose a danger to people, automobiles, and the like. Of course, it may be used in construction sites, civil engineering sites, etc. to prevent danger from falling objects.

  The manufacturing method of the net used in the present invention is as follows. That is, a core-sheath type composite long fiber in which the core component is composed of a high melting point polymer and the sheath component is composed of a low melting point polymer, and the mass ratio of the core component to the sheath component is core component: sheath component = 1-3: 1. A step of preparing a multifilament yarn formed by bundling a plurality of yarns, a step of obtaining a precursor network composed of a mesh leg and a knot using a yarn obtained by aligning a plurality of the multifilament yarns, and the precursor network It comprises a step of heat-treating the ground and solidifying after melting only the sheath component in the yarn constituting the braid and knot. In the last step, the core component is present in the sheath component that is the mother body while maintaining the original fiber form, and the network legs and knots are based on the low-melting point polymer, and a plurality of them are contained in the mother body. This is a fiber-reinforced plastic material in which high-melting polymer fibers are present.

  Next, each step will be described. First, a core-sheath type composite long fiber in which a core component is composed of a high melting point polymer and a sheath component is composed of a low melting point polymer is prepared. In the core-sheath type composite continuous fiber, the mass ratio of the core component to the sheath component is core component: sheath component = 1-3: 1. The low melting point polymer which is a sheath component is a base material for the fiber reinforced plastic material. Therefore, when the mass ratio of the sheath component is lower than this range, it becomes difficult to become a mother body. Moreover, when the mass ratio of the sheath component is higher than this range, the diameter or number of the core component is reduced, and the strength of the fiber-reinforced plastic material is reduced. The fineness of the core-sheath type composite continuous fiber is about 4 to 20 dtex. A plurality of such core-sheath type composite continuous fibers are bundled to form a multifilament yarn. The number of focusing is about 30 to 400.

  Next, a plurality of multifilament yarns are aligned to obtain a yarn. The number of lines is about 5 to 20. Then, by using this yarn, it is hung on a braided netting machine, a braided netting machine or a Russell knitting machine to obtain a netting composed of netting legs and knots. When hanging on a braided net machine, a net leg is obtained by using a plurality of 3 to 5 yarns and assembling them. When hanging on a braid machine, one yarn may be used, but it is preferable to twist and use a plurality of about 2 to 4 yarns. In the case of hanging on a Russell knitting machine, a single yarn is generally used. The core-sheath type composite continuous fibers constituting the yarns are in close contact with each other by assembling or twisting a plurality of yarns, and even if the subsequent heat treatment step is performed without pressing, it is a sheath component A low-melting-point polymer is likely to become a matrix. When hung on a braided netting machine or a braided netting machine, the knot may be knotless or knotted, but it is preferable that the knot be knotless in order to flatten the net.

  The resulting precursor network is heat treated. The heat treatment temperature is equal to or higher than the melting point of the low-melting polymer as the sheath component, and is specifically about 140 to 200 ° C. By this heat treatment, only the sheath component of the core-sheath type composite continuous fiber constituting the yarn is melted. The heat treatment may be performed under pressure or without pressure, but is preferably performed without pressure in order to give flexibility. After the heat treatment, when cooled, the melted sheath component is solidified, and a fiber reinforced plastic material having a low melting point polymer whose bases 1 and knots 2 are sheath components becomes a base material. That is, the fiber reinforcement in which the net legs 1 and the knots 2 exist in a state where the high melting point polymer fiber as the core component maintains the original fiber form in the low melting point polymer as the base sheath component. A net made of plastic material is obtained.

  In the peeling protection net according to the present invention, the net legs and knots are formed of a high-strength fiber-reinforced plastic material having a low-melting polymer as a base and encapsulating a high-melting polymer fiber. Therefore, it is more rigid than the conventional synthetic fiber yarn net, and even when it is stretched on the underside of the overhead or the like, there is an effect that it is difficult to hang down. In addition, since it is made of only a synthetic resin, it is rigid and has a certain flexibility, and it is easy to follow the underside of an elevated body and to be easily stretched.

Example 1
The core component is polyethylene terephthalate having a melting point of 260 ° C. and the sheath component is a copolymer polyester having a melting point of 140 ° C., so that the core component: sheath component = 2.7: 1 (mass ratio) and the core-sheath type having a fineness of about 8.7 dtex. A composite long fiber was prepared. 192 core-sheath type composite long fibers were converged to obtain a multifilament yarn of 1670 dtex / 192 filaments. Using this multifilament yarn, the inserted yarn and the loop yarn were made into a net using a Russell knitting machine to obtain a Russell net. The Russell network was introduced into a pin tenter type heat treatment machine and heat treated for 3 minutes in an atmosphere at 150 ° C. while applying tension in the width direction. Then, by leaving it to stand in room temperature and cooling, a mesh having a mesh size of 10 mm was obtained.

Example 2
A similar network was obtained in the same manner as in Example 1 except that a copolyester having a melting point of 160 ° C. was used as the sheath component and the heat treatment temperature was 180 ° C.

Example 3
A similar network was obtained in the same manner as in Example 1 except that a copolyester having a melting point of 180 ° C. was used as the sheath component and the heat treatment temperature was 200 ° C.

Example 4
A similar network was obtained in the same manner as in Example 1 except that a copolyester having a melting point of 220 ° C was used as the sheath component and the heat treatment temperature was 240 ° C.

Example 5
A core-sheath type composite long fiber having a fineness of about 8.7 dtex in which the core component is polyethylene terephthalate having a melting point of 260 ° C. and the sheath component is polyethylene having a melting point of 130 ° C. and the core component: sheath component = 3: 1 (mass ratio). Got ready. 192 core-sheath type composite long fibers were converged to obtain a multifilament yarn of 1670 dtex / 192 filaments. Thereafter, a Russell network was obtained by the same method as in Example 1, and heat treatment was performed to obtain a similar network.

Example 6
A core-sheath type composite length having a fineness of about 7.3 decitex in which the core component is polyamide 6 having a melting point of 225 ° C. and the sheath component is a copolymer polyamide having a melting point of 155 ° C., the core component: sheath component = 3: 1 (mass ratio). Fiber was prepared. 192 core-sheath type composite long fibers were converged to obtain a multifilament yarn of 1400 dtex / 192 filaments. Thereafter, a similar network was obtained in the same manner as in Example 1 except that the heat treatment temperature was 175 ° C.

Example 7
The core component is polyethylene terephthalate having a melting point of 260 ° C. and the sheath component is a copolymer polyester having a melting point of 140 ° C., so that the core component: sheath component = 2.7: 1 (mass ratio) and the core-sheath type having a fineness of about 8.7 dtex. A composite long fiber was prepared. 192 core-sheath type composite long fibers were converged to obtain a multifilament yarn of 1670 dtex / 192 filaments. Four multifilament yarns were aligned to obtain a yarn. While twisting these two yarns (with two-twisting), they were hung on a braided netting machine to obtain a knotless network. This knotless network was introduced into a pin tenter type heat treatment machine and heat treated for 3 minutes in an atmosphere at 150 ° C. while applying tension in the width direction. Then, by leaving it to stand in room temperature and cooling, a mesh having a mesh size of 10 mm was obtained.

Example 8
A similar network was obtained in the same manner as in Example 7 except that a copolyester having a melting point of 160 ° C. was used as the sheath component and the heat treatment temperature was 180 ° C.

Example 9
A similar network was obtained in the same manner as in Example 7 except that a copolyester having a melting point of 180 ° C. was used as the sheath component and the heat treatment temperature was 200 ° C.

Example 10
A similar network was obtained in the same manner as in Example 7 except that a copolyester having a melting point of 220 ° C. was used as the sheath component and the heat treatment temperature was 240 ° C.

Example 11
A core-sheath type composite long fiber having a fineness of about 8.7 dtex in which the core component is polyethylene terephthalate having a melting point of 260 ° C. and the sheath component is polyethylene having a melting point of 130 ° C. and the core component: sheath component = 3: 1 (mass ratio). Got ready. 192 core-sheath type composite long fibers were converged to obtain a multifilament yarn of 1670 dtex / 192 filaments. Thereafter, in the same manner as in Example 7, a knotless network was obtained and heat-treated to obtain a similar network.

Example 12
A core-sheath type composite length having a fineness of about 7.3 decitex in which the core component is polyamide 6 having a melting point of 225 ° C. and the sheath component is a copolymer polyamide having a melting point of 155 ° C., the core component: sheath component = 3: 1 (mass ratio). Fiber was prepared. 192 core-sheath type composite long fibers were converged to obtain a multifilament yarn of 1400 dtex / 192 filaments. Thereafter, a similar network was obtained in the same manner as in Example 7 except that the heat treatment temperature was 175 ° C.

Example 13
The core component is polyethylene terephthalate having a melting point of 260 ° C. and the sheath component is a copolymer polyester having a melting point of 140 ° C., so that the core component: sheath component = 2.7: 1 (mass ratio) and the core-sheath type having a fineness of about 8.7 dtex. A composite long fiber was prepared. 192 core-sheath type composite long fibers were converged to obtain a multifilament yarn of 1670 dtex / 192 filaments. Two of these multifilament yarns were aligned to obtain a yarn. The four knots were hung on a braided netting machine, and knotted nets were obtained while assembling the net legs. This knotless network was introduced into a pin tenter type heat treatment machine and heat treated for 3 minutes in an atmosphere at 150 ° C. while applying tension in the width direction. Then, by leaving it to stand in room temperature and cooling, a mesh having a mesh size of 10 mm was obtained.

Example 14
A similar network was obtained in the same manner as in Example 13 except that a copolyester having a melting point of 160 ° C. was used as the sheath component and the heat treatment temperature was 180 ° C.

Example 15
A similar network was obtained in the same manner as in Example 13 except that a copolymer polyester having a melting point of 180 ° C. was used as the sheath component and the heat treatment temperature was 200 ° C.

Example 16
A similar network was obtained in the same manner as in Example 13 except that a copolyester having a melting point of 220 ° C. was used as the sheath component and the heat treatment temperature was 240 ° C.

Example 17
A core-sheath type composite long fiber having a fineness of about 8.7 dtex in which the core component is polyethylene terephthalate having a melting point of 260 ° C. and the sheath component is polyethylene having a melting point of 130 ° C. and the core component: sheath component = 3: 1 (mass ratio). Got ready. 192 core-sheath type composite long fibers were converged to obtain a multifilament yarn of 1670 dtex / 192 filaments. Thereafter, in the same manner as in Example 13, a knotless network was obtained and heat-treated to obtain a similar network.

Example 18
A core-sheath type composite length having a fineness of about 7.3 decitex in which the core component is polyamide 6 having a melting point of 225 ° C. and the sheath component is a copolymer polyamide having a melting point of 155 ° C., the core component: sheath component = 3: 1 (mass ratio). Fiber was prepared. 192 core-sheath type composite long fibers were converged to obtain a multifilament yarn of 1400 dtex / 192 filaments. Thereafter, a similar network was obtained in the same manner as in Example 13 except that the heat treatment temperature was 175 ° C.

Comparative Example 1
Instead of the core-sheath type composite long fiber, a single-phase type long fiber having a fineness of about 8.7 dtex made of a polyethylene terephthalate single component having a melting point of 260 ° C. was used, and the heat treatment temperature was 160 ° C. Similar netting was obtained in the same way.

Comparative Example 2
Instead of the core-sheath type composite long fiber, a single-phase type long fiber having a fineness of about 7.3 dtex composed of a single component of polyamide 6 having a melting point of 225 ° C. was used, and the heat treatment temperature was 150 ° C. Similar netting was obtained in the same way.

Comparative Example 3
Instead of the core-sheath type composite long fiber, a single-phase type long fiber having a fineness of about 8.7 dtex composed of a single component of polyethylene terephthalate having a melting point of 260 ° C. was used except that the heat treatment temperature was 160 ° C. Similar netting was obtained in the same way.

Comparative Example 4
Instead of the core-sheath type composite long fiber, a single-phase type long fiber having a fineness of about 7.3 dtex made of polyamide 6 single component having a melting point of 225 ° C. was used, and the heat treatment temperature was 150 ° C. Similar netting was obtained in the same way.

Comparative Example 5
Instead of the core-sheath type composite long fiber, a single-phase type long fiber having a fineness of about 8.7 dtex made of a single component of polyethylene terephthalate having a melting point of 260 ° C. was used except that the heat treatment temperature was 160 ° C. Similar netting was obtained in the same way.

Comparative Example 6
Instead of the core-sheath type composite long fiber, a single-phase type long fiber having a fineness of about 7.3 dtex made of polyamide 6 single component having a melting point of 225 ° C. was used, and the heat treatment temperature was set to 150 ° C. Similar netting was obtained in the same way.

  Test pieces having a length of 150 mm and a width of 50 mm were collected from the nets obtained in Examples 1 to 18 and Comparative Examples 1 to 6. The rigidity of this test piece was evaluated according to the 45 ° cantilever method of JIS L 1096. That is, each test piece is placed on a cantilever testing machine, and each test piece is slid in the direction of the slope. If the test piece comes into contact with the slope, it is evaluated that there is no rigidity. It was evaluated. As a result, all the nets obtained in Examples 1 to 18 were evaluated as having rigidity, but all the nets obtained in Comparative Examples 1 to 6 were evaluated as having no rigidity. Therefore, it can be seen that when the mesh obtained in Examples 1 to 18 is used as a peeling protection net and is stretched on the lower surface of the elevated, the peeling protection net is less likely to hang down.

It is a photograph when a part of peeling protection net concerning an example of the present invention is viewed in plan. It is a photograph when the cross section of the screen leg of the peeling protection net concerning an example of the present invention is observed with a microscope.

DESCRIPTION OF SYMBOLS 1 Netting foot 2 Nodule 3 Eye 4 Fabric 5 Sewing thread 6 Polyethylene 7 Polyethylene terephthalate fiber

Claims (6)

In the peeling protection net consisting of the net used to be stretched on the structure,
The net legs and knots of the net are formed of a fiber reinforced plastic material having a low melting point polymer as a base and a plurality of high melting point polymer fibers in the base, and the low melting point polymer and the nodule A peeling protection net, wherein the mass ratio of the high-melting polymer fiber is low-melting polymer: high-melting polymer fiber = 1: 1 to 3.   2. The peeling protection according to claim 1, wherein the low melting point polymer is derived from the sheath component of the core-sheath type composite long fiber, and the high melting point polymer fiber is derived from the core component of the core-sheath type composite long fiber. Net.   The peeling protection net according to claim 1, wherein the combination of the low melting point polymer and the high melting point polymer fiber is a combination of polyolefin and polyethylene terephthalate fiber, a combination of polyamide A and polyamide B fiber, or a combination of copolymer polyester and polyethylene terephthalate fiber. .   The peeling protection net according to claim 1, wherein a fabric for connecting the mesh or fixing the structure is sewn on an edge of the mesh.   The peeling protection net according to claim 1, wherein the nodule is a nodule.   The peeling protection net according to claim 1, wherein the structure is a concrete structure, and the concrete piece is deteriorated and peeled from the concrete structure.