Double rope structure

Abstract

Provided is a double rope structure comprising an inner core and an outer skin. In the double rope structure, the inner core is composed of high-strength / high-elastic-modulus fibers having a yarn strength of 20 cN / dtex or more and a yarn elastic modulus of 400 cN / dtex or more, and the fitness of the inner layer and the outer layer represented by formula (1) is 0.70-1.20. (a2 / b2) / Vf * 100 (1) In formula (1), a represents the diameter of the outer periphery of the inner core, b represents the diameter of the outer periphery of the outer skin, and Vf represents the volume ratio (%) of the inner core to the total volume of the inner core and the outer skin.

Description

[0001] Related Applications

[0002] This application claims priority based on Japanese Patent Application No. 2022-101743, filed in Japan on June 24, 2022, the entire contents of which are incorporated by reference as a part of this application. Technical Field

[0003] The present invention relates to a double rope structure composed of an inner core (inner layer) and an outer sheath (outer layer). Background Art

[0004] Ropes are made by twisting or braiding multiple strands of wire into cables or ropes. They can be used for mooring ships, fishing nets, and other water-based purposes, as well as for hauling cables and load-bearing cables. A strand of wire is made of multiple yarns, and a yarn is made of multiple single yarns as raw yarns.

[0005] In addition to the rope structure of a single-layer structure, there is also a rope structure of a double structure. The rope structure of the double structure is formed by arranging a bundle of twisted or woven wires in the inner core and the outer sheath, respectively. For example, Patent Document 1 (Utility Model Registration No. 3199266) discloses a fiber rope, which is a double-structured fiber rope formed of a core material and an outer sheath rope covering the outer side thereof, wherein the core material is formed of high-strength / high elastic modulus fiber, and the outer sheath rope is a rope woven from yarns in which high-strength / high elastic modulus fiber and general-purpose fiber are mixed, and in the outer sheath rope, the high-strength / high elastic modulus fiber is mixed more than the general-purpose fiber.

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent Document 1: Utility Model Registration No. 3199266 Summary of the invention

[0009] Problems to be solved by the invention

[0010] However, Patent Document 1 proposes to deal with "friction" by using general-purpose fibers and high-strength / high-elastic modulus fibers in a specific ratio in the sheath. It records that a closer fit between the core material and the sheath will make the rope as a whole less likely to deform. On the other hand, it also records that insufficient twisting and excessive softness of the core material will make it less resistant to bending and twisting.

[0011] Therefore, an object of the present invention is to provide a double rope structure having excellent bending resistance and strength per unit cross-sectional area.

[0012] Solutions to the problem

[0013] The inventors of the present invention have conducted intensive research to achieve the above-mentioned purpose, and as a result, they have confirmed that when a high-strength / high elastic modulus fiber is used as the inner core of a double rope structure, the strength of the rope structure can be improved due to the strength characteristics of the high-strength / high elastic modulus fiber, but on the other hand, they have also found that there is room for improvement in the bendability of the rope structure. Then, as a result of further research, they have found that when there is a moderate gap between the inner core and the outer skin, the bendability of the entire rope structure can be unexpectedly improved, and the strength per unit cross-sectional area of ​​the rope structure can be increased, thereby completing the present invention.

[0014] That is, the present invention can be constituted in the following aspects.

[0015] [Method 1]

[0016] A double rope structure, which consists of an inner core and an outer skin, wherein:

[0017] The inner core is composed of high-strength / high-elasticity modulus fibers having a yarn strength of 20 cN / dtex or more and a yarn elastic modulus of 400 cN / dtex or more.

[0018] The inner and outer layer fit represented by the following formula (1) is 0.70 to 1.20 (preferably 0.80 to 1.15, more preferably 0.85 to 1.10),

[0019] (a 2 / b 2 ) / Vf×100 (1)

[0020] In formula (1), a represents the diameter of the outer periphery of the inner core, b represents the diameter of the outer periphery of the outer skin, and Vf represents the volume ratio (%) of the inner core to the total volume of the inner core and the outer skin.

[0021] [Method 2]

[0022] A double rope structure according to embodiment 1, wherein:

[0023] Relative to the total volume of the inner core and the outer skin, the volume ratio Vf of the inner core is greater than 10% (preferably greater than 15%, more preferably greater than 20%, further preferably greater than 25%, for example, it can be less than 75%, preferably less than 70%, more preferably less than 65%, further preferably less than 60%).

[0024] [Method 3]

[0025] A double rope structure according to embodiment 1, wherein:

[0026] The above-mentioned double rope structure is cut into a given length to obtain a cut portion, and the ratio of the average value of the yarn length of the yarn constituting the inner core of the above-mentioned cut portion to the rope length of the above-mentioned cut portion is 1.005~1.400 (preferably 1.005~1.200, more preferably 1.006~1.180, and further preferably 1.007~1.150) in terms of yarn length / rope length.

[0027] [Method 4]

[0028] The double rope structure according to any one of aspects 1 to 3, wherein:

[0029] The tensile strength of the double rope structure per unit cross-sectional area measured in accordance with JIS L 1013:2021 is 180N / mm 2 Above (preferably 200N / mm 2 More preferably 220N / mm 2 above).

[0030] [Method 5]

[0031] The double rope structure according to any one of aspects 1 to 4, wherein:

[0032] The yarn elongation of the high-strength / high-elastic modulus fiber is 1 to 6% (preferably 2 to 5.5%).

[0033] [Method 6]

[0034] The double rope structure according to any one of aspects 1 to 5, wherein:

[0035] The high strength / high elastic modulus fiber is selected from liquid crystal polyester fiber, ultra-high molecular weight polyethylene fiber, aromatic polyamide fiber, and poly (p-phenylene benzodione) At least one of azole) fibers.

[0036] [Method 7]

[0037] The double rope structure according to any one of aspects 1 to 6, wherein:

[0038] The ratio of the strength of the fibers used for the outer skin to the strength of the fibers used for the inner core is 0.10 to 0.40 (preferably 0.12 to 0.35).

[0039] [Method 8]

[0040] The double rope structure according to any one of aspects 1 to 7, wherein:

[0041] The outer skin is substantially composed of non-high strength / non-high elastic modulus fibers.

[0042] [Method 9]

[0043] The double rope structure according to any one of aspects 1 to 8, wherein:

[0044] The outer sheath is formed of multifilaments.

[0045] [Method 10]

[0046] The double rope structure according to any one of aspects 1 to 9, wherein:

[0047] When a bending test was performed in which bending R was set to 7.5 mm and bending angle was 240° and bending was repeated 10,000 times under a load of 1% of the tensile breaking strength of the rope, the ratio of the tensile strength of the double rope structure after the bending test to the tensile strength of the double rope structure before the bending test was 90% or more.

[0048] When used in this specification, the singular form, "a", "an" and "the" include plural forms including "at least one", unless the content clearly indicates otherwise. When used in this specification, the terms "and / or", "at least 1" and "more than 1" include any and all combinations of the related listed items.

[0049] It should be noted that any combination of at least two constituent elements disclosed in the claims and / or the specification and / or the drawings is included in the present invention. In particular, any combination of two or more of the claims recorded in the claims is also included in the present invention.

[0050] Effects of the Invention

[0051] According to the present invention, since the inner core is made of high-strength and high-elastic modulus fiber yarn and the outer skin is formed with an appropriate gap between the inner core and the outer skin, the bending resistance of the rope structure and the strength per unit cross-sectional area can be improved at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] The present invention can be more clearly understood by describing the following preferred embodiments with reference to the accompanying drawings. However, the embodiments and drawings are only for illustration and description and should not be used to limit the scope of the present invention. The scope of the present invention is determined by the accompanying claims.

[0053] Figure 1 This is a schematic cross-sectional view for explaining a double rope structure according to an embodiment of the present invention.

[0054] Figure 2This is a schematic exploded side view of a double rope structure according to one embodiment of the present invention.

[0055] Figure 3 It will form Figure 2 A simplified three-dimensional diagram of a partially enlarged portion of the inner core wire harness of a double rope structure.

[0056] Figure 4 This is a schematic perspective view for explaining the relationship between the length of one yarn among a plurality of yarns of a wire bundle forming a cut portion of a double rope structure and the length of the cut portion.

[0057] Figure 5 This is a schematic exploded side view of a double rope structure according to another embodiment of the present invention. DETAILED DESCRIPTION

[0058] (Double rope structure)

[0059] The double rope structure is composed of an inner core and an outer skin, wherein the inner core uses high-strength / high-elastic modulus fiber yarn. The double rope structure has a moderate gap between the high-strength / high-elastic modulus fiber yarn of the inner core and the outer skin, so the rope structure is soft as a whole, which can not only improve the bending resistance but also improve the strength per unit cross-sectional area of ​​the rope structure.

[0060] In the double rope structure, the inner and outer layer conformity expressed by the following formula (1) is controlled within a given range.

[0061] (a 2 / b 2 ) / Vf×100 (1)

[0062] In formula (1), a represents the diameter (mm) of the outer circumference of the inner core, b represents the diameter (mm) of the outer circumference of the outer skin, and Vf represents the volume ratio (%) of the inner core to the total volume of the inner core and the outer skin.

[0063] The diameter b of the outer periphery of the outer skin is a value obtained by clamping the double rope structure 10 with the outer measurement jaws of an electronic vernier caliper and measuring it.

[0064] The diameter a of the outer periphery of the inner core is a value obtained by clamping the inner core obtained by removing the outer skin from the double rope structure with the outer measurement jaws of an electronic vernier caliper and measuring it.

[0065] Specifically, these diameters can be measured by the methods described in Examples described later.

[0066] The fit of the inner and outer layers is 0.70~1.20. When the fit of the inner and outer layers is less than 0.70, the inner core rope cannot be tightened by the outer skin, and the gap between the inner core and the outer skin increases. When there are many such gaps, the outer skin will be crushed by the hollow part generated inside the rope, and the strength of the outer skin cannot be maintained, and the strength of the entire rope decreases.

[0067] On the other hand, when the inner and outer layer fit exceeds 1.20, the inner core is tightened too much by the outer skin, resulting in a very hard rope with poor flexibility. Such a rope suffers from severe abrasion between fibers every time the rope is deformed, and has poor bending resistance.

[0068] The inner and outer layer conformity is preferably 0.80 to 1.15, more preferably 0.85 to 1.10. By twisting or braiding so that the inner and outer layer conformity is within the above range, an appropriate gap is present between the inner core and the outer sheath, so that the rope structure is soft as a whole and the bending resistance can be improved.

[0069] The volume ratio Vf of the inner core relative to the total volume of the inner core and the outer skin is the ratio (%) of the total volume occupied by the fibers of the inner core to the total volume occupied by the fibers of the double rope structure in a sample obtained by cutting the double rope structure to a given length (1.000m).

[0070] When calculating the volume ratio Vf,

[0071] (i) After measuring the weight of the sample, separate it into the outer sheath and the inner core, and measure the weight (g) of each fiber group for each fiber type constituting the outer sheath and the inner core.

[0072] (ii) Divide the weight of each fiber group by the density (g / cm2) specific to that fiber type. 3 ), and the volume of each fiber group is calculated.

[0073] (iii) calculating the volume Vo as the sum of the volumes of the fiber groups constituting the outer skin, and calculating the volume Vi as the sum of the volumes of the fiber groups constituting the inner core,

[0074] (iv) The volume ratio Vf can be obtained according to the following formula.

[0075] Vf=(Vi) / (Vi+Vo)×100

[0076] When the sheath is formed of a single fiber type, the weight (Wo) of the fibers constituting the sheath can be obtained by subtracting the weight (Wi) of the fibers constituting the core from the weight (Wo+Wi) of the sample.

[0077] The volume ratio Vf of the inner core relative to the total volume of the inner core and the outer skin may be, for example, 10% or more, preferably 15% or more, more preferably 20% or more, and even more preferably 25% or more. When the volume ratio of the inner core is large, the strength of the double rope structure can be increased by the high-strength / high-elastic modulus fiber yarn. The upper limit of the volume ratio Vf of the inner core is not particularly limited, but from the viewpoint of improving the covering property by the outer skin, the upper limit of the volume ratio Vf of the inner core may be, for example, 75% or less, preferably 70% or less, more preferably 65% ​​or less, and even more preferably 60% or less.

[0078] Since the double rope structure has excellent bending resistance, when a bending test is performed in which the bending R is set to 7.5 mm and the bending angle is 240° under a load of 1% of the tensile breaking strength of the rope, the ratio of the tensile strength of the double rope structure after the bending test to the tensile strength of the double rope structure before the bending test, that is, the bending retention rate (%) can be 90% or more, preferably 93% or more, and more preferably 95% or more. The bending retention rate is a value measured by the method described in the examples described later. The upper limit of the bending retention rate is usually 100%.

[0079] For the double rope structure, since the strength per unit cross-sectional area of ​​the rope structure can be increased, the tensile strength per unit cross-sectional area of ​​the double rope structure measured based on JIS L 1013:2021 can be 180 N / mm 2 Above, preferably 200N / mm 2 More preferably, it can be 220N / mm 2 The upper limit is not particularly limited, and may be, for example, 2000 N / mm 2 .

[0080] Hereinafter, the present invention will be described in detail based on examples. Figure 1 This is a schematic cross-sectional view for explaining a double rope structure.

[0081] like Figure 1 As shown, the double rope structure 10 has an inner core 1 having an outer diameter a and an outer skin 2 having an outer diameter b obtained by braiding the inner core 1. It should be noted that the gap between the inner core 1 and the outer skin 2 is omitted in the figure, and the outer diameter b of the outer skin is also the diameter of the double rope structure 10.

[0082] When the outer sheath 2 is braided, the yarn fineness, number of strands, and spacing of the outer sheath 2 are controlled according to the diameter of the inner core 1, the weight and density of the inner core, etc., so that the fit between the inner and outer layers is within a given range. As a result, the double rope structure can improve the bending resistance and strength per unit cross-sectional area.

[0083] Figure 2 1 is a schematic exploded side view of a double rope structure according to an embodiment of the present invention. Figure 3 Yes Figure 2 A three-dimensional simplified diagram of a part of the harness 3 forming the inner core of the double rope structure is enlarged. Figure 2 As shown, the double rope structure 10 comprises an inner core 1 and an outer skin 2 covering the inner core, wherein the outer skin 2 is a braided fabric and is integrated with the inner core 1 to form the double rope structure. Figure 2 In the figure, the outer skin 2 is partially omitted in order to show the state of the inner core 1.

[0084] The inner core 1 and the outer sheath 2 have a structure in which a plurality of wire bundles are twisted and / or woven, each of which is composed of a plurality of yarns, each of which is composed of a plurality of single yarns twisted in a specific range. Each single yarn may be a monofilament or a multifilament.

[0085] For example, Figure 3 As shown, the formation Figure 2 The wire bundle 3 of the inner core 1 of the double rope structure 10 is composed of a plurality of yarns 4, each of which is a twisted body formed by twisting a plurality of original yarns (preferably monofilaments or multifilaments, particularly preferably multifilaments).

[0086] Figure 2 1A of the inner core 1 is shown. The cut portion 1A represents the inner core portion when the double rope structure 10 is cut at the given length V. If the cut portion 1A is decomposed, a plurality of wire bundles constituting the cut portion 1A can be obtained. Figure 2 In the figure, one of the wire bundles 3A is indicated by a dot. The wire bundle 3A is composed of a plurality of yarns (not shown).

[0087] Figure 4 This is a perspective schematic diagram for explaining the relationship between the length W of one yarn 4A among the plurality of yarns forming the cut portion 1A and the length V of the cut portion 1A. The double rope structure 10 is cut into a given length V to obtain the cut portion 1A, and the wire bundle 3A present in the cut portion 1A is decomposed into the yarn 4A. When the length of the yarn 4A is measured, the yarn 4A has a length W.

[0088] In the double rope structure of the present invention, in the cut portion 1A, the length W of the yarn 4A forming the wire harness 3A may be within a range of, for example, 1.005 to 1.400 in terms of yarn length / rope length (W / V).

[0089] In addition, with respect to the length direction Z passing through the center of the double rope structure (hereinafter referred to as the rope length direction Z), for example, Figure 2 As shown in FIG. 1 , the bundle 3A constituting the inner core crosses at a crossing angle θ (0°<θ<90°) relative to the rope length direction Z. The crossing angle θ can be measured by photographing the side surface of the fiber with the outer sheath 1 removed and the inner core 2 exposed. For example, Figure 2 In the embodiment, the harness 3A intersecting the rope length direction Z of the double rope structure 10 is randomly selected, and the angle θ formed by the rope length direction Z and one side of the harness 3A on the rope length direction Z side is used as the crossing angle.

[0090] Figure 5 2 is an exploded side view of a double rope structure according to another embodiment of the present invention. The double rope structure 20 comprises an inner core 6 and an outer skin 2 covering the inner core. The outer skin 2 is a braided fabric and is integrated with the inner core 6 to form a double rope structure. Figure 2 The same symbols are used for the common parts and the description is omitted.

[0091] In this double rope structure, when the outer sheath 2 is braided, the inner core 6 and the outer sheath 2 are braided so that the inner and outer layer fit represented by the above formula (1) has a given range, thereby improving the bending resistance and strength per unit cross-sectional area of ​​the double rope structure.

[0092] The inner core 6 has a twisted structure formed by twisting a plurality of wire bundles 7, each of which is composed of a plurality of yarns, and each of which is composed of a plurality of single yarns. Figure 5 The wire harness 7 of the inner core 6 of the double rope structure 20 and Figure 3 The wire harness 3 shown is similarly composed of a plurality of yarns 4, each of which is a twisted body of a plurality of raw yarns (preferably monofilaments or multifilaments, particularly preferably multifilaments).

[0093] Figure 5 6A of the inner core 6 is shown in FIG. The cut portion 6A shows the inner core portion when the double rope structure 20 is cut at a given length V. If the cut portion 6A is decomposed, a plurality of wire bundles constituting the cut portion 6A can be obtained. Figure 5In the figure, one of the wire harnesses 7A is indicated by a dot. The wire harness 7A is composed of a plurality of yarns (not shown), and the length W of the yarns forming the wire harness 7A relative to the length V of the cut portion 6A, for example, in terms of yarn length / rope length (W / V), can be in a range of, for example, greater than 1.005 and less than 1.400.

[0094] In addition, if Figure 5 As shown, the wire bundle 7A constituting the inner core crosses at a crossing angle θ (0°<θ<90°) relative to the rope length direction Z. Figure 5 In the embodiment, the harness 7A intersecting the rope length direction Z passing through the center of the double rope structure 20 is randomly selected, and the angle θ formed by the rope length direction Z and one side of the harness 7A on the rope length direction Z side is used as the crossing angle.

[0095] like Figure 2 and 4 As shown, the outer skin 2 is formed by a braid of wire harnesses. Figure 3 As shown, the wire harness is further composed of a plurality of yarns. Each yarn is a twisted body formed by twisting a plurality of raw yarns (preferably monofilaments or multifilaments, particularly preferably multifilaments).

[0096] Hereinafter, a preferred embodiment of the double rope structure will be described.

[0097] (Inner core)

[0098] The diameter of the inner core can be appropriately set according to the intended use, and may be, for example, 0.5 to 100 mm, preferably 1.0 to 80 mm, and more preferably 1.5 to 60 mm. The diameter of the inner core is a value measured by the method described in the Examples described below.

[0099] In the double rope structure, the twist of each yarn of the multiple yarns constituting the inner core can be, for example, 150 to 0.1 T / m, preferably 100 to 2 T / m, more preferably 80 to 3 T / m, further preferably 70 to 5 T / m, and particularly preferably 60 to 6 T / m. If the twist is small, the strength of the rope can be increased, but if it is not twisted, the handling property when forming the rope bundle is reduced. In addition, the multiple rope bundles constituting the inner core can be twisted as needed. For example, as a reference for the twist of the rope bundle, it can be twisted as needed within the range of the yarn length of the inner core / rope length. In addition, the multiple rope bundles can be further twisted as needed.

[0100] The fineness of the yarn can be appropriately set according to the fineness required for the double rope structure, and can be, for example, 30 to 5000 dtex, preferably 200 to 4000 dtex, more preferably 400 to 2500 dtex, and further preferably 1000 to 2000 dtex. If the yarn fineness is within the above range, it is preferred in terms of handling properties such as convergence of the wire harness.

[0101] In the inner core constituting the double rope structure of the present invention, the ratio of the average yarn length of the yarn constituting the inner core cut into a cut portion of 1 m (to be precise, 1.000 m) to the rope length of the cut portion may be in the range of 1.005 to 1.400, preferably 1.005 to 1.200, more preferably 1.006 to 1.180, and even more preferably 1.007 to 1.150 from the viewpoint of improving the tensile strength of the double rope structure. It should be noted that the yarn length and the rope length are values ​​measured by the method described in the Examples described later.

[0102] The inner core of the double rope structure of the present invention may be a twisted body or a braided fabric. In the case of a twisted body, 3 strands or 4 strands are often used, and a braided fabric may be 4 strands, 6 strands, 8 strands, 12 strands, 16 strands, 32 strands, 64 strands, etc. Among them, a braided fabric is preferred, and a braided fabric of 4 strands, 6 strands, 8 strands, 12 strands, 16 strands, or 32 strands is particularly preferred.

[0103] When twisting or braiding is performed, the pitch (mesh / inch) can be adjusted to, for example, 2.5 to 25, preferably 2.5 to 20, more preferably 3 to 18, and even more preferably 3.3 to 15. The pitch means the number of yarns per inch in the length direction of the rope, and can be confirmed by measuring using a digital microscope VHX-2000 manufactured by KEYENCE, for example.

[0104] The crossing angle θ of the harness with respect to the length direction of the rope may be, for example, 50° or less, preferably 40° or less, more preferably 35° or less, further preferably 33° or less, further more preferably 30° or less, and particularly preferably 27° or less. The lower limit of the crossing angle may be, for example, 2° or more, preferably 3° or more, more preferably 6° or more, and further preferably 10° or more. When the crossing angle of the harness is less than the upper limit, it is preferred in terms of strength, and when it is greater than the lower limit, it is preferred in terms of bending durability.

[0105] The high-strength / high-elastic modulus fiber constituting the inner core is not particularly limited as long as it can achieve a yarn strength of 20 cN / dtex or more and a yarn elastic modulus of 400 cN / dtex or more. Specific examples include: liquid crystal polyester fibers (Vectran (trademark), Siveras (trademark), Zexion (trademark), etc.), ultra-high molecular weight polyethylene fibers (Izanas (trademark), Dyneema (trademark), etc.), aramid fibers (Kevelar (trademark), Twaron (trademark), Technora (trademark), etc.), poly(p-phenylene benzodipamide ... etc.), poly(p-phenylene benzodipamide), poly(p-phenylene benzodipamide), etc.), and poly(p-phenylene benzodipamide). azole) fiber (Zylon (trademark) etc.)

[0106] The yarn strength of the high-strength / high-elastic modulus fiber is 20 cN / dtex or more, preferably 22 cN / dtex or more. The upper limit is not particularly limited, and may be 40 cN / dtex, for example.

[0107] In addition, the yarn elastic modulus of the high-strength / high elastic modulus fiber is 400 cN / dtex or more, preferably 450 cN / dtex or more. The upper limit is not particularly limited, for example, it can be 600 cN / dtex. In addition, the yarn elongation of the high-strength / high elastic modulus fiber can be, for example, 1 to 6%, preferably 2 to 5.5%.

[0108] The yarn strength, yarn elastic modulus and yarn elongation are values ​​measured by the methods described in the examples described later.

[0109] By using such high-strength / high-elastic modulus fibers, it is possible to achieve high strength per unit cross-sectional area in the double rope structure.

[0110] Among these high-strength / high-elastic modulus fibers, liquid crystal polyester fibers, ultra-high molecular weight polyethylene fibers, or aramid fibers are preferred.

[0111] Liquid crystal polyester fibers can be produced, for example, by melt spinning a liquid crystal polyester and further subjecting the spun yarn to solid phase polymerization. Liquid crystal polyester multifilaments are fibers formed by aggregating two or more liquid crystal polyester monofilaments.

[0112] Liquid crystal polyester is a polyester that shows optical anisotropy (liquid crystallinity) in the molten phase, and can be identified, for example, by placing a sample on a heating table, heating it in a nitrogen atmosphere, and observing the transmitted light of the sample with a polarizing microscope. In addition, the liquid crystal polyester includes, for example, repeating structural units derived from aromatic diols, aromatic dicarboxylic acids, or aromatic hydroxycarboxylic acids, and the chemical composition of the above structural units is not particularly limited as long as the effect of the present invention is not impaired. In addition, within the scope of not impairing the effect of the present invention, the liquid crystal polyester may include structural units derived from aromatic diamines, aromatic hydroxyamines, or aromatic aminocarboxylic acids.

[0113] For example, preferred structural units include those shown in Table 1.

[0114] [Table 1]

[0115]

[0116] (Wherein, X in the formula is selected from the following structures)

[0117]

[0118] (wherein m=0-2, Y=is a substituent selected from hydrogen, halogen, alkyl, aryl, aralkyl, alkoxy, aryloxy, and aralkyloxy)

[0119] Here, Y is present in a number ranging from 1 to the maximum number of substitutable groups in the aromatic ring, and is independently selected from a hydrogen atom, a halogen atom (e.g., a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc.), an alkyl group (e.g., an alkyl group having 1 to 4 carbon atoms, such as a methyl group, an ethyl group, an isopropyl group, a tert-butyl group, etc.), an alkoxy group (e.g., a methoxy group, an ethoxy group, an isopropoxy group, an n-butoxy group, etc.), an aryl group (e.g., a phenyl group, a naphthyl group, etc.), an aralkyl group [benzyl (phenylmethyl), phenethyl (phenylethyl)), etc.], an aryloxy group (e.g., a phenoxy group, etc.), and an aralkyloxy group (e.g., a benzyloxy group, etc.).

[0120] More preferred structural units include the structural units described in Examples (1) to (18) shown in Tables 2, 3 and 4. In the case where the structural unit in the formula is a structural unit that can show a plurality of structures, two or more such structural units may be combined and used as the structural unit constituting the polymer.

[0121] [Table 2]

[0122]

[0123] [Table 3]

[0124]

[0125] [Table 4]

[0126]

[0127] In the structural units of Tables 2, 3 and 4, n is an integer of 1 or 2, and each structural unit wherein n=1 or n=2 may exist alone or in combination, and Y1 and Y2 may each independently be a hydrogen atom, a halogen atom (e.g., a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc.), an alkyl group (e.g., an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, an isopropyl group, a tert-butyl group, etc.), an alkoxy group (e.g., a methoxy group, an ethoxy group, an isopropoxy group, an n-butoxy group, etc.), an aryl group (e.g., a phenyl group, a naphthyl group, etc.), an aralkyl group [benzyl (phenylmethyl), phenethyl (phenylethyl) group, etc.], an aryloxy group (e.g., a phenoxy group, etc.), an aralkyloxy group (e.g., a benzyloxy group, etc.), etc. Among them, preferred Y1 and Y2 include a hydrogen atom, a chlorine atom, a bromine atom or a methyl group.

[0128] In addition, as Z, there can be mentioned substituents represented by the following formulae.

[0129] [Chemical formula 1]

[0130]

[0131] The preferred liquid crystal polyester preferably has two or more naphthalene skeletons as structural units. It is particularly preferred that the liquid crystal polyester comprises both structural units (A) from hydroxybenzoic acid and structural units (B) from hydroxynaphthoic acid. For example, as structural unit (A), the following formula (A) can be cited, and as structural unit (B), the following formula (B) can be cited. From the viewpoint of easily improving melt moldability, the ratio of structural unit (A) to structural unit (B) can preferably be 9 / 1~1 / 1, more preferably 7 / 1~1 / 1, and further preferably 5 / 1~1 / 1.

[0132] [Chemical formula 2]

[0133]

[0134] [Chemical formula 3]

[0135]

[0136] In addition, the total amount of the structural unit of (A) and the structural unit of (B) can be 65 mol% or more, more preferably 70 mol% or more, and further preferably 80 mol% or more relative to all structural units. In the polymer, a liquid crystal polyester in which the structural unit of (B) is 4 to 45 mol% is particularly preferred.

[0137] The melting point of the liquid crystal polyester that can be suitably used in the present invention is preferably 250 to 360° C., more preferably 260 to 320° C. Here, the melting point refers to the main absorption peak temperature observed by measuring with a differential scanning calorimeter (DSC; "TA3000" manufactured by METTLER) based on the JIS K7121:2012 test method. Specifically, in the above-mentioned DSC device, 10 to 20 mg of the sample can be taken and sealed in an aluminum pan, and nitrogen as a carrier gas is circulated at 100 cc / min, and the temperature is raised at 20° C. / min, and the endothermic peak at this time is measured. Depending on the type of polymer, when no clear peak appears in the 1st run in the DSC measurement, the temperature is increased at a rate of 50°C / min to a temperature 50°C higher than the expected flow temperature, and maintained at this temperature for 3 minutes. After complete melting, it is cooled to 50°C at a rate of -80°C / min, and then the endothermic peak is measured at a rate of 20°C / min.

[0138] It should be noted that, within the scope of not impairing the effects of the present invention, thermoplastic polymers such as polyethylene terephthalate, modified polyethylene terephthalate, polyolefin, polycarbonate, polyamide, polyphenylene sulfide, polyetheretherketone and fluororesin can be added to the above-mentioned liquid crystal polyester. In addition, various additives such as inorganic substances such as titanium oxide, kaolin, silicon dioxide, barium oxide, colorants such as carbon black, dyes, pigments, antioxidants, ultraviolet absorbers, and light stabilizers can also be added.

[0139] (Outer skin)

[0140] In the double rope structure of the present invention, the outer sheath is composed of a twisted body or a braided fabric of a wire bundle covering an inner core. The yarn constituting the wire bundle may be a monofilament or a multifilament, and is preferably a multifilament.

[0141] The twisted body can be formed by winding the wire bundle into a spiral shape with respect to the inner core, and the braid can be formed by braiding 8, 12, 16, 24, 32, 40, 48, 64 strands, etc. with the inner core as the core. Among them, a braid of 12, 16, 24, 32, 40, or 48 strands is preferred, and a braid of 12, 16, 24, 32, or 40 strands is more preferred.

[0142] The wire bundle constituting the outer skin may be formed by the above-mentioned high-strength / high elastic modulus fiber, or may be formed by non-high-strength / non-high elastic modulus fiber. For non-high-strength / non-high elastic modulus fiber, for example, the yarn strength may be less than 20 cN / dtex, and may generally be about 1 cN / dtex to 15 cN / dtex. The yarn elastic modulus may be less than 400 cN / dtex, and may generally be about 10 cN / dtex to 200 cN / dtex. The yarn elongation may be, for example, 3 to 20%, and preferably 7 to 20%.

[0143] For non-high-strength / non-high-elastic modulus fibers, from the perspective of ensuring the strength of the inner core, the ratio of the strength of the fiber used in the outer sheath to the strength of the fiber used in the inner core may be, for example, in the range of 0.10 to 0.40, preferably in the range of 0.12 to 0.35.

[0144] Specific non-high-strength / non-high-elastic modulus fibers include general-purpose synthetic fibers, such as general-purpose polyester fibers (e.g., polyethylene terephthalate fibers), polyolefin fibers (e.g., polyethylene fibers, polypropylene fibers), polyamide fibers (e.g., nylon 6 fibers, nylon 6,6 fibers), polyvinyl alcohol fibers (e.g., vinylon (trademark)), etc.), and the like.

[0145] In the case of a double rope structure, since the strength of the rope structure can be ensured by the inner core, the outer skin can be substantially composed of non-high-strength / non-high-elastic modulus fibers. Here, substantially means that the proportion of non-high-strength / non-high-elastic modulus fibers in the outer skin is 80% by weight or more, preferably 90% by weight or more (90 to 100% by weight).

[0146] The fineness of the yarn of the bundle forming the outer sheath can be appropriately set according to the diameter required for the double rope structure, for example, it can be 50 to 100,000 dtex, preferably 100 to 50,000 dtex, more preferably 200 to 40,000 dtex, further preferably 200 to 10,000 dtex, and further preferably 200 to 1,000 dtex. When the fineness of the yarn of the bundle forming the outer sheath is within the above range, it is easy to adjust the fit between the inner and outer layers.

[0147] The diameter of the double rope structure, that is, the diameter b of the outer periphery of the outer skin, can be appropriately set according to the application, and can be, for example, 1.0 to 250 mm, preferably 1.5 to 200 mm, and more preferably 1.8 to 100 mm. Here, the diameter b is the diameter of the outer periphery of the outer skin 2, and is a value obtained by clamping the double rope structure 10 with the outer measurement jaws of an electronic vernier caliper.

[0148] Example

[0149] The present invention will be described in more detail below by way of examples, but the present invention is not limited to these examples. It should be noted that in the following examples and comparative examples, various physical properties were measured by the following methods.

[0150] [Diameter and cross-sectional area]

[0151] The diameters of the double rope structure and the inner core were measured at seven random points by clamping with the outer measuring jaws of an electronic vernier caliper, and then calculated from the average value of the five points after excluding the maximum and minimum values.

[0152] Here, the diameter of the double rope structure is used as the diameter of the outer periphery of the outer skin.

[0153] It should be noted that when measuring the diameter of the inner core, the outer skin is carefully removed from the surface layer while the inner core is stretched so as not to affect the structure of the inner core of the double rope structure, and only the inner core portion is clamped with the outer measuring jaws of the electronic vernier caliper for measurement.

[0154] In addition, the cross-sectional area of ​​the double rope structure is calculated by dividing the diameter of the double rope structure by (diameter / 2) 2 ×3.14 to calculate.

[0155] [Volume ratio]

[0156] 1.000m was randomly selected and cut from the double rope structure, and its weight was measured using an electronic precision balance (weight of the double rope structure: Wi + Wo). After the above measurement, the outer skin was carefully removed while the inner core was stretched, and the weight of the outer skin (outer skin weight: Wo) and the weight of the inner core (inner core weight: Wi) were measured using an electronic precision balance.

[0157] Then, the volume ratio Vf (%) of the inner core to the total volume of the inner core and the outer skin is calculated according to the following formula.

[0158] Vf=(Wi / ρi) / (Wi / ρi+Wo / ρo)×100

[0159] Here, Wi is the weight of the inner core (g), ρi is the density of the inner core (g / cm 3 ), Wo is the weight of the outer skin (g), ρo is the density of the outer skin (g / cm 3 ).

[0160] In the above formula, the density of the inner core and the outer sheath is determined by utilizing the density of the polymer constituting the yarn forming the inner core and the outer sheath.

[0161] [Rope length / Inner core yarn length]

[0162] A 1.000 m portion is randomly selected from a double rope structure (hereinafter sometimes referred to as a rope structure) and cut to obtain the rope length. In addition, the wire bundles constituting the cut portion are disassembled to take out the inner core, and further, one of the wire bundles constituting the inner core is arbitrarily selected to obtain the yarn constituting the inner core. The lengths of all the obtained inner core yarns are measured in a taut state based on JIS L 1013:2021, and the average value is taken as the yarn length.

[0163] [Yarn fineness (dtex)]

[0164] The wire bundle constituting the rope structure was disassembled to obtain yarns constituting the inner core and the outer sheath, and the yarn fineness of the obtained yarn was measured in accordance with JIS L 1013:2021.

[0165] [Yarn strength (N) / Yarn strength (cN / dtex) / Yarn elongation (%) / Yarn elastic modulus (cN / dtex)]

[0166] The wire bundle constituting the rope structure was decomposed to obtain the yarn constituting the inner core. The tensile strength of the obtained yarn was measured as the yarn strength (N) based on JIS L1013:2021, and the yarn elongation and yarn elastic modulus were measured. In addition, the value obtained by dividing the yarn strength (cN) by the yarn fineness (dtex) was taken as the yarn strength (cN / dtex).

[0167] [Pitch (mesh / inch)]

[0168] The number of yarns present per inch in the rope was measured using a digital microscope VHX-2000 manufactured by KEYENCE, and the measured number was defined as the pitch.

[0169] [Cross Angle]

[0170] The angle of the wire bundle in the inner core of the double rope structure with respect to the longitudinal direction of the rope was measured using a digital microscope VHX-2000 manufactured by KEYENCE Corporation.

[0171] [Tensile strength per unit cross-sectional area of ​​the rope (N / mm 2 )]

[0172] For the double rope structure, a vortex-type jig for rope evaluation (manufactured by Chubu Machinery Co., Ltd.) was used as a clamping jig of the universal testing machine, and the rope was wound around the groove part of the vortex part. The rope was fixed by the friction resistance of the surface, and the tensile strength of the double rope structure was measured based on JIS L 1013:2021. In addition, the diameter of the double rope structure was measured and the cross-sectional area was calculated. The obtained tensile strength was divided by the cross-sectional area, and the obtained value was used as the tensile strength per unit cross-sectional area of ​​the rope.

[0173] [Bending resistance: Strength retention after bending test (%)]

[0174] In a bending tester (TC111L / Yuasa System), a tension-free bending test jig (DX-TFB / Yuasa System Co., Ltd.) was used, and the bending R was set to 7.5 mm. A bending test was performed at a bending angle of 240° and a load of 1% of the tensile breaking strength of the rope for 10,000 times. The tensile strength of the double rope structure before and after the bending test was measured. As the strength retention rate after the bending test, the tensile strength of the double rope structure after the bending test relative to the tensile strength of the double rope structure before the bending test was calculated and expressed as a percentage.

[0175] [Example 1]

[0176] As a high-strength / high-elastic modulus fiber, liquid crystal polyester multifilament ("Vectran" manufactured by Kuraray Co., Ltd., with a fineness of 1670 dtex) was used, and an inner core rope was manufactured by adjusting the rotation speed and extraction speed of the braiding machine for an EL type 6-strand rope making machine (manufactured by Kokubun Limited) so that the pitch became 8.6 mesh / inch.

[0177] The obtained inner core rope was used as the core material, and polyethylene terephthalate multifilament (manufactured by Toray Industries, Ltd., fineness 280 dtex, yarn strength 7.2 cN / dtex, yarn elastic modulus 88 cN / dtex, yarn elongation 15.1%) was used. For a medium-sized 32-strand rope-making machine (manufactured by Kokubun Limited), the rotation speed and withdrawal speed of the braiding machine were adjusted so that the pitch became 50 mesh / inch, and a double rope was manufactured.

[0178] [Example 2]

[0179] A double rope structure was produced in the same manner as in Example 1 except that the number of strands and the pitch of the inner core of the double rope structure and the fineness and the pitch of the outer sheath were changed as shown in Table 5. The results are shown in Table 5.

[0180] [Example 3]

[0181] A double rope structure was produced in the same manner as in Example 1 except that the high strength / high elastic modulus fiber as the inner core of the double rope structure was changed to an ultra-high molecular weight polyethylene multifilament (manufactured by Toyobo Co., Ltd., "Izanas", fineness 1760 dtex), the pitch of the inner core was changed to 8.5, and the pitch of the outer sheath was changed to 49. The results are shown in Table 5.

[0182] [Example 4]

[0183] A double rope structure was produced in the same manner as in Example 3 except that the number of strands and the pitch of the inner core of the double rope structure and the fineness, number of strands and the pitch of the outer sheath were changed as shown in Table 5. The results are shown in Table 5.

[0184] [Example 5]

[0185] As a high-strength / high-elastic modulus fiber, a liquid crystal polyester multifilament ("Vectran", manufactured by Kuraray Co., Ltd., with a fineness of 1670 dtex) was used, 38 strands were wound on a bobbin by a winder under a certain tension to produce 38 bundled yarns, and the bundled yarns were further wound on a bobbin by a winder under a certain tension to obtain a rope-making wire bundle (fineness 2,411,480 dtex). Then, for the rope-making wire bundle, the rotation speed and extraction speed of the braiding machine were adjusted in a 6-strand rope-making machine so that the pitch was 0.45 mesh / inch, and an inner core rope was produced.

[0186] Using polyethylene terephthalate multifilament (manufactured by Toray Industries, Ltd., fineness 1100 dtex, yarn strength 6.8 cN / dtex, yarn elastic modulus 88 cN / dtex, yarn elongation 14%), 20 strands were wound on a bobbin by a winder under a certain tension to produce 20 bundled yarns, and 4 of the bundled yarns were twisted 10 times / m in the Z direction by a twisting machine under a certain tension and wound on a bobbin to obtain a twisted yarn for rope making (fineness 456,000 dtex). Then, using the inner core rope as the core material, the rotation speed and extraction speed of the braiding machine were adjusted in a 32-strand rope making machine so that the pitch was 3.1 mesh / inch, and a double rope structure with an inner and outer layer fit of 1.00 (diameter a around the outer periphery of the inner core: 48 mm, diameter b around the outer periphery of the outer sheath: 76 mm) was produced.

[0187] [Comparative Example 1]

[0188] A double rope structure was produced in the same manner as in Example 1 except that the number of strands and the pitch of the inner core of the double rope structure and the pitch of the outer skin were changed as shown in Table 5. The results are shown in Table 5.

[0189] [Comparative Example 2]

[0190] A double rope structure was produced in the same manner as in Example 2 except that the pitch of the inner core of the double rope structure and the fineness and number of strands of the outer sheath were changed as shown in Table 5. The results are shown in Table 5.

[0191] [Comparative Example 3]

[0192] A double rope structure was produced in the same manner as in Example 3 except that the number of strands and the pitch of the inner core of the double rope structure and the fineness and the pitch of the outer sheath were changed as shown in Table 5. The results are shown in Table 5.

[0193] [Comparative Example 4]

[0194] A double rope structure was produced in the same manner as in Example 4 except that the pitch of the inner core of the double rope structure and the fineness and number of strands of the outer sheath were changed as shown in Table 5. The results are shown in Table 5.

[0195] [Comparative Example 5]

[0196] A double rope structure was produced in the same manner as in Example 1 except that the fiber of the inner core of the double rope structure was changed to polyethylene terephthalate multifilament (manufactured by Toray Industries, Ltd., fineness 1670 dtex, yarn strength 8.0 cN / dtex, yarn elastic modulus 143 cN / dtex, yarn elongation 12.6%), the pitch of the inner core was changed to 9.6, the number of strands was changed to 12, and the pitch of the sheath was changed to 55. The results are shown in Table 5.

[0197]

[0198] As shown in Table 5, for Examples 1 to 4, in any of the examples, the inner and outer layer conformity of the double rope structure is in the range of 0.70 to 1.20, the strength retention rate (%) after the bending test is 90% or more, and the average tensile strength per cross-sectional area is 180 N / mm 2 above.

[0199] On the other hand, in Comparative Examples 1 and 2, the inner and outer layer conformity of the double rope structure was higher than 1.20, and the strength retention rate after the bending test was inferior to that of the Example. In Comparative Examples 3 and 4, the inner and outer layer conformity of the double rope structure was lower than 0.70, and the tensile strength per unit cross-sectional area was inferior to that of the Example. In Comparative Example 5, the fiber constituting the inner core was a non-high strength / non-high elastic modulus fiber, and therefore, the strength of the rope structure as a whole was halved compared to Example 1 having the same diameter.

[0200] Industrial Applicability

[0201] The double rope structure of the present invention can be very preferably used for aquatic uses such as mooring of ships, fishing net rims, mooring of floating water equipment set in a floating state on the water, marine ropes used when mooring floating offshore structures used for marine resource exploration to the seabed, aquatic uses such as towing cables, load-bearing cables, wind power generation equipment, substation equipment, etc., land uses such as towing cables, load-bearing cables, and sports and leisure uses.

[0202] As described above, the preferred embodiments of the present invention are described with reference to the accompanying drawings. Those skilled in the art can refer to the specification of this application and make various additions, changes or deletions without departing from the spirit of the present invention, which are all included in the scope of the present invention.

Claims

1. A double rope structure, which consists of an inner core and an outer skin, wherein: The inner core is composed of high-strength / high-elasticity modulus fibers having a yarn strength of 20 cN / dtex or more and a yarn elastic modulus of 400 cN / dtex or more. The inner and outer layer fit expressed by the following formula (1) is 0.70 to 1.20, (a 2 / b 2 ) / Vf×100 (1) In formula (1), a represents the diameter of the outer periphery of the inner core, b represents the diameter of the outer periphery of the outer skin, and Vf represents the volume ratio (%) of the inner core to the total volume of the inner core and the outer skin.

2. The double rope structure according to claim 1, wherein: A volume ratio Vf of the inner core relative to the total volume of the inner core and the outer skin is 10% or more.

3. The double rope structure according to claim 1, wherein: The double rope structure is cut into a given length to obtain a cut portion, and the ratio of the average yarn length of the yarn constituting the inner core of the cut portion to the rope length of the cut portion is 1.005 or more and 1.400 or less in terms of yarn length / rope length.

4. The double rope structure according to any one of claims 1 to 3, wherein: The tensile strength of the double rope structure per unit cross-sectional area measured in accordance with JIS L 1013:2021 is 180N / mm 2 above.

5. The double rope structure according to any one of claims 1 to 4, wherein: The yarn elongation of high strength / high elastic modulus fibers is 1~6%.

6. The double rope structure according to any one of claims 1 to 5, wherein: The high strength / high elastic modulus fiber is selected from liquid crystal polyester fiber, ultra-high molecular weight polyethylene fiber, aromatic polyamide fiber, and poly (p-phenylene benzodione) At least one of azole) fibers.

7. The double rope structure according to any one of claims 1 to 6, wherein: The ratio of the strength of the fiber used for the outer skin to the strength of the fiber used for the inner core is 0.10 to 0.

40.

8. The double rope structure according to any one of claims 1 to 7, wherein: The outer skin is essentially composed of non-high strength / non-high elastic modulus fibers.

9. The double rope structure according to any one of claims 1 to 8, wherein: The outer sheath is formed of multifilaments.

10. The double rope structure according to any one of claims 1 to 9, wherein: When a bending test was performed in which bending R was set to 7.5 mm and bending angle was 240° and bending was repeated 10,000 times under a load of 1% of the tensile breaking strength of the rope, the ratio of the tensile strength of the double rope structure after the bending test to the tensile strength of the double rope structure before the bending test was 90% or more.

Images