JP2011160762A - Monofilament for fishline and fishline - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a monofilament for fishline which has combined high strength, elasticity, and durability to contact with obstacle and having suitable performance as a fishline, and to provide a fishline comprising the monofilament. <P>SOLUTION: There is provided a monofilament for fishline, wherein the monofilament is provided by melt-spinning a vinylidene fluoride homopolymer having a melt flow rate (230°C, 10 kg) of 1.5-3.5 g/10 min, and a molecular weight distribution Mw/Mn of 2.0-3.0, and the monofilament has a dry tensile strength of 650-1,000 MPa, and a bending hardness index Bhi of 9-13. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a monofilament for fishing line having high strength, flexibility and root slip resistance, and suitable performance as a fishing line, and a fishing line comprising the same.

  A vinylidene fluoride resin (hereinafter abbreviated as PVdF) monofilament has useful properties such as toughness, high specific gravity, close refractive index to water, and low water absorption. Conventionally, it is widely used for fishery materials such as fishing lines and fishing nets and various industrial materials.

  However, PVdF monofilaments are stiffer and less linear than other synthetic fibers such as polyamide-based resin fibers due to the high crystallinity and elastic modulus derived from the fiber structure, and are easy to get a string. There was a problem. That is, when PVdF monofilament is used for fishing lines, for example, it is easy to get a winding rod after being wound on a spool or reel. The point that it was easy to do each became the neck. Also, when PVdF monofilament is used as a luer line with bait reel, once a phenomenon called backlash occurs, backlash often occurs based on the folds attached to the yarn. It was a problem. In this way, the fact that the fishing line is stiff and has poor linearity and is likely to be hooked not only reduces handling, but also causes unnatural movement of lures and fishing baits, which causes damage to the fishing results. It was.

  For the purpose of solving such problems, attempts have been made to soften PVdF monofilaments, and such techniques include monofilaments made of vinylidene fluoride copolymers (see, for example, Patent Document 1) and comonomer components. Monofilaments composed of a PVdF composition containing a vinylidene fluoride copolymer containing 1% by mass or more (for example, see Patent Document 2) have already been proposed, but these monofilaments are flexible, Since its melting point is low, physical properties are lowered due to frictional heat when used as a fishing line, and particularly root displacement resistance and knot strength are apt to be lowered.

  In addition, a PVdF monofilament (for example, see Patent Document 3) having high knot strength and yarn resistance obtained by subjecting a high-viscosity PVdF to an extremely short time high temperature relaxation heat treatment has already been proposed. The monofilament manufacturing method not only requires high temperature relaxation heat treatment to be applied to the normal spinning process, but also uses organic solvents such as glycerin and silicone oil for this heat treatment, which is sufficiently satisfactory from an industrial and environmental standpoint. It wasn't possible.

  Furthermore, phosphorescent tegus and road yarns (for example, see Patent Document 4) made of PVdF, which have excellent durability and operability, have already been proposed, but this tegus is for improving the visibility of road yarns in night fishing. Although it is an invention related to phosphorescent tegus, the PVdF monofilament is provided with flexibility by containing a phosphorescent phosphor, but when used as an underwater thread such as Harris, it causes the fish to be wary and damages the fishing results. However, since the phosphorescent phosphor works as a foreign substance in the yarn, it is not satisfactory in terms of strength.

  As described above, the conventional flexible PVdF monofilament for fishing line is insufficient in terms of physical properties, manufacturing method, and the like, and the actual situation is that improvement is desired.

Japanese Patent Publication No. 5-33059 JP 2002/064867 A JP 2005-105483 A JP 2006-81543 A

  The present invention has been achieved as a result of examining the solution of the problems in the above-described prior art as an object.

  Accordingly, an object of the present invention is to provide a monofilament for fishing line that has high strength, flexibility and resistance to root slip, and has suitable performance as a fishing line, and a fishing line comprising the same.

  In order to achieve the above object, according to the present invention, a fluoride having a melt flow rate (230 ° C., 10 kg) of 1.5 to 3.5 g / 10 min and a molecular weight distribution Mw / Mn of 2.0 to 3.0. A monofilament obtained by melt spinning a vinylidene homopolymer, having a dry tensile strength of 650 to 1000 MPa, and a bending hardness index Bhi represented by the following formula (1) of 9 to 13. Monofilaments are provided.

  However, Bh shows bending hardness [mN] and (phi) shows the diameter [mm] of a monofilament.

In the fishing line of the present invention,
The bending recovery rate of the monofilament is 79% or more, and the vinylidene fluoride homopolymer is 70 to 30% by weight of the vinylidene fluoride component (A) having a weight average molecular weight Mw1, and a weight average molecular weight higher than Mw1 It is a preferable condition that it is composed of 30 to 70% by weight of a vinylidene fluoride component (B) having Mw2, and when these conditions are applied, acquisition of a further excellent effect can be expected. .

  The fishing line of the present invention is characterized by comprising the above-described monofilament for fishing line, and exhibits the best effect particularly when applied as Harris.

According to the present invention, as will be described below, a fishing line monofilament having high strength, flexibility, and resistance to root slip and having suitable performance as a fishing line can be obtained.
Therefore, the monofilament for fishing line of the present invention is extremely useful for various fishing lines, particularly for Harris and lure line applications, taking advantage of the above-described excellent characteristics.

  Hereinafter, the present invention will be specifically described.

  First, the vinylidene fluoride homopolymer constituting the monofilament for fishing line of the present invention will be described.

  A fishing line using a vinylidene fluoride homopolymer becomes a monofilament having a higher melting point than that using a copolymer, and is resistant to frictional heat. As a result, for example, the durability when the thread comes into contact with obstacles such as underwater rocks, sharp shells, concrete and decayed trees, so-called root slip resistance, is improved, and fishing lines or fishing lines and needles are tied together. Sometimes the problem that the strength of the nodule portion becomes weak due to frictional heat is less likely to occur. Accordingly, the melting point of the vinylidene fluoride resin is preferably 170 ° C. or higher for the above reasons.

  For the vinylidene fluoride homopolymer used in the present invention, for example, various additives such as pigments, dyes, light-proofing agents, ultraviolet absorbers, antioxidants, crystallization inhibitors, and plasticizers inhibit the intended performance. As long as it is not added, it may be added after the polymerization step, after polymerization or just before spinning.

  In the monofilament for fishing line of the present invention (hereinafter sometimes simply referred to as monofilament), the melt flow rate (hereinafter referred to as MFR) measured at 230 ° C. and a load of 10 kg according to the method of JIS K 7210 (1999) is 1. It is important to use a vinylidene fluoride homopolymer of 5 to 3.5 g / 10 min, preferably 1.7 to 3.0 g / 10 min. If the MFR is below the above range, the load applied to the screw during melt extrusion becomes too large or the productivity is lowered, which is not preferable. On the other hand, if it exceeds the above range, the tensile strength at the time of making the monofilament is not preferable.

  In the vinylidene fluoride homopolymer used in the present invention, it is also important that the molecular weight distribution Mw / Mn is 2.0 to 3.0, preferably 2.0 to 2.5. Here, Mw represents the weight average molecular weight, Mn represents the number average molecular weight, and the ratio Mw / Mn is generally used as an index representing the breadth of the molecular weight distribution. Conventionally, it was known that the smaller the molecular weight distribution Mw / Mn, the better the monofilament tensile strength. However, if the molecular weight distribution is smaller than the above range, it is not preferable because the molecular weight is uniform, so that the monofilament is easily crystallized and becomes a hard monofilament. Conversely, when the molecular weight distribution Mw / Mn is wider than the above range, crystallization is insufficient, and the tensile strength of the monofilament is so low that it is not suitable for use.

  A vinylidene fluoride homopolymer having a molecular weight distribution Mw / Mn of 2.0 to 3.0 is simply prepared by producing at least two kinds of vinylidene fluoride homopolymers having different average molecular weights by respective polymerization methods. These are obtained by mixing them. That is, according to a preferred embodiment of the present invention, the vinylidene fluoride component A having a weight average molecular weight Mw1 is 70 to 30% by weight, and the vinylidene fluoride component B having a weight average molecular weight Mw2 higher than Mw1 is 30 to 70% by weight. More preferably, a raw material containing 50 to 30% by weight of component A and 50 to 70% by weight of component B can be used. In addition, it is preferable that the weight average molecular weight Mw2 of the component B is 350,000 or more. When this raw material is used, since the component B having a high weight average molecular weight Mw2 maintains high tensile strength and can be mixed with the component A to suppress crystallization, the hardness is improved and a flexible monofilament Is obtained.

  When mixing at least two kinds of vinylidene fluoride homopolymers, a powdered polymer is mixed at a predetermined weight ratio, then supplied to a twin-screw kneading extruder, a dough mixer, etc., and kneaded under heating A method of pelletizing a resin or a method of dry blending a pellet-like polymer can be used.

  The monofilament of the present invention formed by melt spinning using the above-mentioned vinylidene fluoride homopolymer has a dry tensile strength of 650 to 1000 MPa, preferably 680, measured according to the method of JIS L1013 (1999) 8.5.1. It is necessary to be ˜950 MPa, more preferably 700 to 900 MPa. If the dry tensile strength is less than the above range, it is not suitable for use as a fishing line that requires the strength of the straight portion. On the other hand, when the above range is exceeded, the orientation and crystallization are excessively advanced, so that it becomes a hard monofilament.

  Furthermore, as an index of flexibility which is an important characteristic of the monofilament of the present invention, it is important that the bending hardness index Bhi represented by the following formula (1) is 9 to 13, preferably 10 to 12.5. is there.

  However, Bh shows bending hardness [mN] and (PHI) shows the diameter [mm] of a monofilament.

  Here, a method for measuring the bending hardness index Bhi will be described. First, after the monofilament sample was allowed to stand for 24 hours or more under the conditions of a temperature of 20 ° C. and a relative humidity of 65%, a monofilament sample cut to a length of about 4 cm was prepared. Set the sample so that it touches the bottom of a 2mm diameter stainless steel rod installed in the horizontal direction at intervals of 10mm, and hangs a 1mm diameter stainless steel hook on the sample at the center of the stainless steel rod. Using a TCM-200 type universal tensile / compression tester, the stainless steel hook was pulled up at a speed of 50 mm / min, and the maximum stress generated at this time was defined as the bending hardness Bh. The bending hardness index Bhi was calculated using the bending hardness Bh [mN] and the monofilament diameter Φ [mm].

  When this bending hardness index is less than the above range, the monofilament is not stiff, and it is not preferable because it becomes a monofilament that is difficult to handle such as being easily entangled, and as a result, it becomes a fishing line in which folds are easily developed. On the other hand, when the above range is exceeded, the monofilament is too hard, and it cannot be wound up neatly on a spool or reel. .

  Furthermore, the monofilament of the present invention preferably has a flexion recovery rate of 79% or more, and more preferably 80% or more. Here, a method for measuring the bending recovery rate will be described.

  Make a loop of two pairs of monofilaments crossed, fix the upper loop to the clasp, and apply a load (weight [g] of 1/2 the fiber fineness [denier]) to the lower loop for 3 minutes. Thus, a pair of pine needle-shaped samples formed at the intersections of the loops is obtained. A sample was collected by cutting the bent portion into a length of about 3 cm, and the flexion recovery rate was calculated from the opening angle (θ) measured after standing for 60 minutes, using the formula: θ / 180 × 100 [%]. . This bend recovery rate is an important characteristic of fishing line hooks. If the bend recovery rate is less than the above range, the hook tends to develop, and an unfavorable tendency to deteriorate handling properties and damage the fishing results is caused. There are times.

  The monofilament of the present invention can be efficiently produced by the method described below.

  When melt spinning the monofilament, normal conditions using an extruder-type spinning machine can be adopted, the polymer temperature is 220 to 285 ° C., the extrusion pressure is 1 to 50 MPa, the nozzle diameter is 0.1 to 20 mm, the spinning speed. Conditions such as 0.3 to 100 m / min can be appropriately selected.

  The monofilament spun from the extruder is then cooled in a cooling bath after passing through a short gas zone. As the cooling medium here, a liquid inert to the polymer, usually water, glycerin, polyethylene glycol and the like are used.

  The cooled and solidified composite monofilament continues to be sent to the first drawing step. As an atmosphere (bath) for drawing and heat setting, a heated heat medium bath such as warm water, polyethylene glycol, glycerin and silicone oil, hot air is used. A body bath and a steam bath are used.

  In the stretching step, one-stage to multi-stage stretching is performed, and a preferable total stretching ratio is usually 5.0 times or more, preferably 5.5 times or more.

  After the one-step or multi-step stretching, an appropriate constant length and / or relaxation heat treatment can be performed for the purpose of removing stretching strain as necessary.

  The monofilament of the present invention may be colored or dyed after spinning or during spinning using an existing method. Moreover, you may give finishing oil etc. to the surface of a monofilament.

  Furthermore, the outer shape of the monofilament of the present invention is not necessarily limited to a circular cross section, and can take any shape such as a triangular cross section, a square cross section, and a multi-leaf cross section. It does not exclude the secondary processing such as twisting or twisting a single yarn.

  As described above, the monofilament of the present invention has a melt flow rate (230 ° C., 10 kg) of 1.5 to 3.5 g / 10 minutes and a molecular weight distribution Mw / Mn of 2.0 to 3.0. Since the vinylidene homopolymer is melt-spun and has a dry tensile strength of 650 to 1000 MPa and a bending hardness index Bhi of 9 to 13, it has higher strength than a conventional monofilament made of vinylidene fluoride resin. It has both flexibility and resistance to root displacement, and has suitable performance as a fishing line.

  Therefore, the monofilament of the present invention is extremely useful for various fishing lines, particularly for Harris and lure line applications, taking advantage of the above-described excellent characteristics.

  Hereinafter, the present invention will be described based on examples. Evaluation of monofilaments in the examples was performed according to the following method.

[Melt flow rate (MFR)]
According to JIS K 7210 (1999), the measurement was performed at 230 ° C. and a load of 10 kg.

[Weight average molecular weight (Mw) and number average molecular weight (Mn)]
Using a gel permeation chromatography (GPC) device “GPC-900” manufactured by JASCO Corporation, “Sodex KD-806M” manufactured by Showa Denko KK for the column, “Sodex KD-G” for the precolumn, and NMP for the solvent. The polystyrene-converted molecular weight was measured by the GPC method at a temperature of 40 ° C. and a flow rate of 10 mL / min. In principle, monofilaments were used as samples.

[Dry tensile strength and dry joint strength]
According to JIS L 1013 (2008) 8.5.1 and 8.6.1, measurement was performed at a grip interval of 25 cm and a tensile speed of 30 cm / min.

[Bending hardness index]
After the monofilament sample was allowed to stand for 24 hours or more under the conditions of a temperature of 20 ° C. and a relative humidity of 65%, a monofilament sample cut to a length of about 4 cm was prepared. Set the sample so that it touches the bottom of a 2mm diameter stainless steel rod installed in the horizontal direction at intervals of 10mm, and hangs a 1mm diameter stainless steel hook on the sample at the center of the stainless steel rod. Using a “TCM-200 universal tensile / compression tester”, the stainless steel hook was pulled up at a speed of 50 mm / min, and the maximum stress generated at this time was defined as the bending hardness Bh. Then, using this bending hardness Bh [mN] and the monofilament diameter Φ [mm], the bending hardness index Bhi was calculated by the following formula (1).

[Bending recovery rate]
A pair of two loops crossed from the monofilament is made, the upper loop is fixed to the clasp, and a load (weight [g] of 1/2 of the fiber fineness [denier]) is applied to the lower loop for 3 minutes. Thus, a pair of pine needle-shaped samples formed at the intersections of the loops is obtained. A sample was collected by cutting the bent portion into a length of about 3 cm, and the flexion recovery rate was calculated from the opening angle (θ) measured after standing for 60 minutes, using the formula: θ / 180 × 100 [%]. . The fiber fineness [denier] represents the weight of the yarn per 9000 m (1 denier = 1 g / 9000 m). The number of measurements was 4, and the average value was shown. The larger the value, the better the bend recovery.

[Root root resistance]
A device was used in which eight rubbing rods made of a stainless steel rod having a square section with a side of 10 mm square were attached to the outer periphery of a rotating frame having a diameter of 130 mm and a length of 240 mm in parallel and at equal intervals. A weight of 3 kg per unit cross-sectional area [mm ² ] of the fishing line is attached to one end of a 400 mm long fishing line (monofilament), and the other end is connected to the slide shaft. The fishing line in this state is suspended from the rotating frame so as to contact the corners of the six rubbing rods. Then, by traversing the slide shaft while showering water on the fishing line, the rotating frame is moved in the weight direction at a rotational speed of 250 rpm while giving the fishing line a reciprocating movement with a width of 20 mm and a speed of 60 seconds one way. Rotate for 60 seconds. The fishing line after this treatment is collected, its tensile strength is measured in accordance with JIS L1013, and the strength retention [%] with respect to the tensile strength before treatment is calculated. Higher strength retention means better root resistance.

[Melting point of resin]
Using “DSC22” manufactured by Seiko Denshi Kogyo Co., Ltd., 5.00 mg of monofilament sample was set, heated from room temperature to 300 ° C. at a heating rate of 10 ° C./min (1st run), held for 5 minutes, then returned to room temperature, The temperature was raised again from room temperature to 300 ° C. at a rate of temperature increase of 10 ° C./min (2nd run). The melting point of the resin was determined from the endothermic peak of 2nd run.

[Actual fishing evaluation]
Several anglers evaluated actual fishing as Harris, and the evaluation results were expressed in the following three stages.
◎… Satisfied with all strength, flexibility and root resistance, suitable for fishing.
○: There is a problem in any of strength, flexibility, and rooting resistance, but fishing is possible.
X: There was a serious problem in any of strength, flexibility, and root resistance, and it was impossible to continue fishing or it was not suitable for fishing.

[Example 1]
As a vinylidene fluoride homopolymer, component A (Solvey Solexis, “Solef (registered trademark) 1013”, Mw1 = 340000) 50% by weight and component B (Solvey Solexis, “Solef (registered trademark) 1015”, Mw2 = 4800000) After mixing both powdered polymers using 50% by weight, the mixture was fed to a twin-screw kneading extruder and kneaded under heating to form resin pellets, MFR = 2.0 g / 10 min, molecular weight distribution Mw A raw material of /Mn=2.41 was obtained. This raw material was melted by an extruder type spinning machine at a spinning temperature of 260 ° C., and a monofilament was spun through a die having a diameter of 2.0 mm. The monofilament was passed through a space having an atmosphere length of 150 mm heated to a temperature of 300 ° C. provided immediately below the die, and immediately cooled in a polyethylene glycol solution at 20 ° C.

  Next, this undrawn yarn is first-stage drawn 5.8 times in a polyethylene glycol bath at 165 ° C., and subsequently passed through a dry heat bath at 155 ° C. at a treatment magnification of 0.9 times for heat treatment. A monofilament having a diameter of 0.205 mm was obtained. The characteristics of the fishing line made of this monofilament are shown in Table 1.

[Example 2]
As a vinylidene fluoride homopolymer, 30% by weight of the component A (“Solef® 1013”) and 70% by weight of the B component (“Solef® 1015”) were mixed together. Thereafter, the mixture was fed to a twin-screw kneading extruder and kneaded under heating to form resin pellets, whereby a raw material having an MFR = 1.7 g / 10 min and a molecular weight distribution Mw / Mn = 2.33 was obtained. A monofilament having a diameter of 0.128 mm was obtained in the same manner as in Example 1 except that this raw material was used and the base diameter was 1.3 mm. The characteristics of the fishing line made of this monofilament are shown in Table 1.

[Example 3]
As a vinylidene fluoride homopolymer, “Solef (registered trademark) 1013” was pelletized to obtain a raw material having an MFR = 3.0 g / 10 minutes and a molecular weight distribution Mw / Mn = 2.27. A monofilament having a diameter of 0.380 mm was obtained in the same manner as in Example 1 except that this raw material was used. The characteristics of the fishing line made of this monofilament are shown in Table 1.

[Example 4]
The same as Example 1 except that resin pellets (MFR = 2.9 g / 10 min, molecular weight distribution Mw / Mn = 2.20) of “Solef® 6013” were used as the vinylidene fluoride homopolymer. Thus, a monofilament having a diameter of 0.205 mm was obtained. The characteristics of the fishing line made of this monofilament are shown in Table 1.

[Comparative Example 1]
As a vinylidene fluoride homopolymer, “Neofluon VP832” manufactured by Daikin Industries in the form of pellets was used. This raw material had MFR = 3.5 g / 10 min and molecular weight distribution Mw / Mn = 1.84. A monofilament having a diameter of 0.205 mm was obtained in the same manner as in Example 1 except that this raw material was used. The characteristics of the fishing line made of this monofilament are shown in Table 1.

[Comparative Example 2]
As a vinylidene fluoride homopolymer, “Solef (registered trademark) 1012”, “Solef (registered trademark) 1013”, and “Solef (registered trademark) 1015” were used at 30 wt%, 30 wt%, and 40 wt%, respectively. After the polymer is mixed, it is fed to a twin-screw kneading extruder and is kneaded under heating to form a resin pellet, and a raw material with MFR = 3.5 g / 10 min and molecular weight distribution Mw / Mn = 3.24 is obtained. Obtained. A monofilament having a diameter of 0.205 mm was obtained in the same manner as in Example 1 except that this raw material was used. The characteristics of the fishing line made of this monofilament are shown in Table 1.

[Comparative Example 3]
As a vinylidene fluoride homopolymer, powdered “Solef (registered trademark) 1015” was pelletized and tried to be used. However, the melt viscosity was too high to be pelletized, and spinning was impossible. This powder raw material had MFR = 0.7 g / 10 min, molecular weight distribution Mw / Mn = 1.95, and melting point 173 ° C.

[Comparative Example 4]
“Solef® 1012” pelletized as a vinylidene fluoride homopolymer was used. This raw material had MFR = 5.0 g / 10 min and molecular weight distribution Mw / Mn = 2.68. A monofilament having a diameter of 0.261 mm was obtained in the same manner as in Example 1 except that this raw material was used. The characteristics of the fishing line made of this monofilament are shown in Table 1.

[Comparative Example 5]
“Solef (registered trademark) 11010”, which is a copolymer of vinylidene fluoride and hexafluoropropylene, was used as a raw material resin. This raw material had MFR = 70.2 g / 10 min and molecular weight distribution Mw / Mn = 2.75. A monofilament having a diameter of 0.205 mm was obtained in the same manner as in Example 1 except that this raw material was used. The characteristics of the fishing line made of this monofilament are shown in Table 1.

[Comparative Example 6]
“VP-830” manufactured by Daikin was used as the vinylidene fluoride homopolymer. This raw material had MFR = 4.4 g / 10 min and molecular weight distribution Mw / Mn = 1.87. A mixture containing 10% by weight of “N Yoko Luminaba GLL300FFS” (SrAl ₂ O ₄ · Eu, Dy) manufactured by Nemoto Special Chemical Co., Ltd. with respect to 90% by weight of this raw material was used with an extruder-type spinning machine at a spinning temperature of 260 ° C. After melting, the monofilament was spun through a 2.5 mm diameter die. A monofilament having a diameter of 0.285 mm was obtained in the same manner as in Example 1 except for this.
Subsequently, the monofilament was subjected to high-temperature and short-time heat treatment for the purpose of obtaining high strength. With the monofilament wound up, the monofilament was preliminarily dried in a dryer at 70 ° C. for 24 hours to adjust the moisture content of the monofilament to 0.03%. Then, high-temperature short-time heat treatment was performed at 710 ° C. for 0.1 second while pulling the pre-dried monofilament from the winding tool.

  Table 1 shows the characteristics of these monofilaments and fishing lines made of them.

  As is apparent from Table 1, the fishing line of the present invention has both high strength, flexibility and resistance to root displacement, and is superior to conventional ones especially when used as a Harris or lure line.

  On the other hand, the fishing line using the raw material having a narrow molecular weight distribution (Comparative Example 1) was excellent in tensile strength, but was not sufficiently flexible and not satisfactory in terms of hardness. Although the fishing line (comparative example 2) using the raw material with a wide molecular weight distribution has flexibility, it has insufficient tensile strength and cannot withstand actual fishing. In addition, fishing lines using a raw material with a low melt flow rate (MFR) (Comparative Example 3) cannot be spun, and fishing lines using a raw material with a high MFR (Comparative Example 4) cannot withstand actual fishing due to insufficient tensile strength. It was. The fishing line using the copolymer resin (Comparative Example 5) was insufficient in tensile strength and was not satisfactory in terms of anti-root misalignment, and could not withstand actual fishing. A fishing line (Comparative Example 6) using a raw material resin having a low MFR and a narrow molecular weight distribution and containing a phosphorescent phosphor gives not only strong strength and insufficient root resistance, but also gives a warning to the fish. The result was significantly impaired.

  As described above, the fishing line of the present invention has high strength, flexibility, and resistance to root displacement compared with a conventional monofilament made of vinylidene fluoride resin, and has suitable performance as a fishing line. Therefore, taking advantage of these excellent characteristics, it is extremely useful for various fishing lines, especially Harris and lure line applications.

Claims (5)

A monofilament obtained by melt spinning a vinylidene fluoride homopolymer having a melt flow rate (230 ° C., 10 kg) of 1.5 to 3.5 g / 10 min and a molecular weight distribution Mw / Mn of 2.0 to 3.0. A fishing line monofilament having a dry tensile strength of 650 to 1000 MPa and a bending hardness index Bhi represented by the following formula (1) of 9 to 13.

However, Bh shows bending hardness [mN] and (phi) shows the diameter [mm] of a monofilament. The monofilament for fishing line according to claim 1, wherein a bending recovery rate of the monofilament is 79% or more. The vinylidene fluoride homopolymer is a vinylidene fluoride component (A) having a weight average molecular weight Mw1 of 70 to 30% by weight and a vinylidene fluoride component (B) having a weight average molecular weight Mw2 higher than Mw1 of 30 to 70% by weight. The fishing line monofilament according to claim 1 or 2, characterized by comprising: A fishing line comprising the monofilament for fishing line according to any one of claims 1 to 3. The fishing line according to claim 4, wherein the fishing line is Harris.