JPH11323041A - Plastic optical fiber cable - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject cable, harmless, excellent in scratch resistance and flexibility and useful for a personal computer, an audiovisual instrument, etc., by including a covering layer of a resin composition containing a specific block copolymer, a specific polypropylene resin mixture or the like in a specific ratio. SOLUTION: This plastic optical fiber cable contains a covering layer of a resin composition consisting of (A) 100 pts.wt. one or more kinds of block copolymers having 30,000-400,000 number-average molecular weight and consisting of 10-50 wt.% >=2 polymer blocks consisting mainly of styrene and >=1 polymer blocks obtained by hydrogenating a polymer consisting mainly of a conjugated diene, (B) 5-900 pts.wt. polypropylene resin mixture containing 15-60 wt.% ethylene component, consisting of a polypropylene homopolymer or the like and a propylene-ethylene copolymer or the like containing <=75 wt.% propylene, (C) 0-200 pts.wt. hydrocarbon oil and (D) 0-15 pts.wt. polyolefinic resin other than the component (B).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plastic optical fiber cable used for personal computers, audiovisual equipment, exchanges, telephones, OA equipment and FA equipment.

[0002]

2. Description of the Related Art Conventional plastic optical fiber cable coating resins include polyethylene resin, olefin-based elastomer resin, polyvinyl chloride resin, polyurethane resin, polyamide resin, polyester elastomer resin and the like. The most general ones are polyethylene resins and polyvinyl chloride resins. Among them, polyvinyl chloride is an essential feature of the resin that it is resistant to scratches, that it can be processed into a high-quality cable with a very soft touch depending on the formulation, and that it has excellent flame retardancy. There is a mainstream cable used in familiar places such as audio cables and OA cables.

[0003]

However, polyvinyl chloride resins have begun to be avoided from the viewpoint of environmental problems. The present invention relates to a plastic optical fiber cable comprising a harmless covering material having the characteristics of polyvinyl chloride, which has been conventionally used as a covering material for cables. That is, the present invention provides a plastic optical fiber cable comprising a coating material having excellent scratch resistance, flexibility, weather resistance, heat resistance, low-temperature properties, coating workability, and, in some cases, excellent flame retardancy. Things.

[0004]

That is, the present invention relates to (a) two or more polymer blocks A mainly composed of styrene and one or more polymer blocks A obtained by hydrogenating a polymer mainly composed of a conjugated diene compound. (B) 100 parts by weight of at least one kind of a block copolymer having a number average molecular weight of 30,000 to 400,000 and comprising a total of 10 to 50% by weight of the polymer block B; A propylene-α-olefin copolymer containing 85% by weight or more of propylene, or a propylene-ethylene copolymer containing 85% by weight or more of propylene, and a propylene-ethylene copolymer containing 75% by weight or less of propylene Or a mixture of a propylene-ethylene-α-olefin copolymer containing 75% by weight or less of propylene. 5 to 900 parts by weight of a polypropylene resin mixture having a content of ethylene component of 15 to 60% by weight (c) 0 to 200 parts by weight of a hydrocarbon oil (d) 0 to 150 parts by weight of a polyolefin resin other than (b) 1 is a plastic optical fiber cable having a coating layer made of a resin composition.

[0005] The polymer block A mainly composed of styrene constituting the hydrogenated block copolymer which is the component (a) constituting the coating resin of the present invention is 10 to 10 of the hydrogenated block copolymer.
50% by weight. If the amount is less than 10% by weight, the mechanical strength and the heat resistance decrease, so that it is not preferable. If the amount exceeds 50% by weight, the scratch resistance and the flexibility decrease, which is not preferable. Examples of the conjugated diene compound include butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-
One or more of 1,3-butadiene and the like can be selected. The number average molecular weight of the hydrogenated block copolymer in the present invention is 30,000 to 400,000. If the number average molecular weight of the hydrogenated block copolymer is less than 30,000, strength and heat resistance are undesirably reduced. On the other hand, if it exceeds 400,000, the molding processability deteriorates and it cannot be used. The molecular weight distribution (Mw / Mn) of the hydrogenated block copolymer is 5 or less, preferably 2 or less, more preferably 1.5 or less, as indicated by a value determined by GPC analysis based on standard polystyrene. If it exceeds 5, the mechanical strength and heat resistance are not sufficient, which is not preferable.

The method for producing these block copolymers can be described by, for example, producing a block copolymer of a styrene-conjugated diene compound before hydrogenation by a method described in Japanese Patent Publication No. 40-23798. Can be done. Examples of the method of hydrogenation include, for example, JP-B-42-8704, JP-B-43-6636, and JP-A-60-220.
147, JP-A-61-33132 and JP-A-62-207303. The aliphatic double bond derived from the conjugated diene compound is hydrogenated so that at least 80%, preferably 90% or more of the styrene block is hydrogenated, while less than 20%, preferably less than 10% of the styrene block is hydrogenated. Selected. The hydrogenation rate of these hydrogenated block copolymers can be known by infrared spectroscopy or NMR analysis. These hydrogenated block copolymers may be composed of a plurality of types.

[0007] The polypropylene resin mixture as the component (b) of the present invention is a propylene-α-olefin copolymer containing 85% by weight or more of propylene or a propylene-ethylene copolymer containing 85% by weight or more of propylene. A mixture of a polymer and a propylene-ethylene copolymer containing 75% by weight or less of propylene or a propylene-ethylene-α-olefin copolymer containing 75% by weight or less of propylene, and the content of the ethylene component in the mixture. Is 15 to 60% by weight, and it is particularly preferable that the rubber phase formed by mixing is finely and evenly distributed in the polypropylene matrix. Such a mixture may be, for example, one produced by a method in which a mixture is formed simultaneously with polymerization in a polymerization vessel, and such a polypropylene resin mixture has plastic elasticity. Compared to a mixture by blending, the coating resin composition of the present invention has much better scratch resistance, and has a role of forming a cable coating layer having a smooth molded appearance while maintaining the scratch resistance and flexibility of the coating resin composition of the present invention.

A more preferable example of a method for producing a mixture in which such polymerization and mixing are carried out simultaneously is a propylene copolymer mixture obtained by sequential polymerization of two or more stages. In the first step, a propylene homopolymer, a propylene-α-olefin copolymer containing 85% by weight or more of propylene, or a propylene-ethylene copolymer containing 85% by weight or more of propylene is produced. Propylene-ethylene copolymer containing 75% by weight or less of propylene or propylene containing 75% by weight or less of propylene in the second step while being present in the reactor
A mixture of polypropylene is produced while producing an ethylene-α-olefin copolymer. The polymerization of propylene in the first step is carried out in such an amount that the resulting polypropylene has an isotactic index of 80% or more, preferably 85% or more, more preferably 90% or more.
It can be carried out in the presence of an olefin, such as butene-1, pentene-1, 4-methylpentene 1, hexene 1, and octene 1 or a combination thereof. The monomers used in the second step are propylene, ethylene and α-olefin. In this step, butadiene, 1,1, and 2 were used in an amount of 10% by weight or less based on the weight of all monomers.
It can also be carried out in the presence of a diene such as 4 hexadiene or 1-5 hexadiene. And in such a production method, the amount of the polypropylene resin in the first reaction step is 10 to
60% by weight, preferably 15 to 50% by weight, and the amount of the polypropylene resin in the second reaction step is 40 to 90% by weight, preferably 50 to 85% by weight. The total amount of ethylene copolymerized in the polypropylene resin mixture of the component (b) is 15 to 65% by weight, preferably 17 to 45% by weight, and more preferably 20 to 35% by weight. The amount of all α-olefins copolymerized in the polypropylene resin mixture of (b) is 0 to 30% by weight, preferably 3 to 20% by weight,
More preferably, it is 5 to 10% by weight. The polypropylene resin mixture (b) shows at least one melting peak at a temperature of 120 ° C. or higher as measured by differential scanning calorimetry.

Further, the mixture (b) has a flexural modulus of 20 to
Preferably, it is 700 MPa. Further, the Shore D hardness is preferably 20 to 60, more preferably 20 to 50.
It is. Further, the melt flow rate of the mixture (b) (AST
MD 1238, 230 ° C, 2.16Kg load)
100 g / 10 min is preferable, and 30 to 6 is more preferable.
0 g / 10 minutes. If it is less than 2 g / 10 minutes, it becomes difficult to coat the plastic optical fiber smoothly. If it exceeds 100 g / 10 minutes, the mechanical strength and heat resistance decrease, which is not preferable. As a polymerization method of the polypropylene mixture of the component (b), for example, JP-A No. 3-2
05439, JP-A-6-25367, JP-A-6-25489 and the like.

As such a polypropylene mixture, Adflex, Hifax (manufactured by Montell, Inc.)
(Catalloy TPO series) and can be easily obtained. The blending amount of the polypropylene resin mixture of the component (b) in the coating resin of the present invention is 5 to 900 parts by weight based on 100 parts by weight of the hydrogenated block copolymer (a). As this amount increases, the rubber elasticity decreases. On the other hand, if the amount is less than 5 parts by weight, the appearance of the cable deteriorates, which is not preferable. From such a viewpoint, the coating resin for the plastic optical fiber cable is more preferably 5 to 100 parts by weight.

The component (c) in the present invention is a hydrocarbon oil, which has the effect of improving the flexibility and processability of the resulting composition. Paraffin oils and naphthenic oils can be used. it can. The blending amount of the hydrocarbon oil is 0 to 20 with respect to 100 parts by weight of the hydrogenated block copolymer.
0 parts by weight. If the blending amount of the hydrocarbon oil is large, the scratch resistance and the heat resistance decrease. More preferred compounding amount is 10-6.
0 parts by weight.

Next, the polyolefin resin other than the component (d) (b) of the present invention is specifically a polyethylene resin or a polypropylene resin, and includes low-density polyethylene, high-density polyethylene, and linear low-density polyethylene. polyethylene,
Other examples include a copolymer of ethylene and an α-olefin having 3 to 8 carbon atoms. As the α-olefin, propylene, butene 1, isobutene, pentene 1, hexene 1,
4-methylpentene 1, octene 1 and the like.
The polypropylene resin is a homopolymer of propylene or a copolymer of propylene and an α-olefin having 2 to 8 carbon atoms. The melt flow rate of these polyolefin resins is 5 to 100 g / 10 minutes. 5g
If it is less than / 10 minutes, the fluidity is low and the molded appearance is not good. 1
On the other hand, when it is more than 00 g / 10 minutes, the mechanical strength and the heat resistance are undesirably reduced. In the present invention, the polyolefin resin (d) has the effect of adjusting the hardness of the coating resin and improving the processability, and the compounding amount is 100 parts by weight of the hydrogenated block copolymer (a). 20 to 150 parts by weight. If the amount is less than 20 parts by weight, heat resistance and fluidity decrease, which is not preferable. If the amount exceeds 150 parts by weight, flexibility decreases, which is not preferable. Well, these (a), (b),
If necessary, a heat stabilizer, a light stabilizer, a flame retardant, a colorant, and the like are added to the basic resin composition comprising (c) and (d).
Additives such as inorganic fillers may be added to form a coating resin.

As the heat stabilizer, a hindered phenol-based antioxidant is preferable, and as the light stabilizer, a hindered amine-based light stabilizer having a molecular weight of 1500 or more is preferable because it does not give coloring to the plastic optical fiber. Particularly when it is necessary to make the flame retardant, it is very effective to add a halogen-free magnesium hydroxide and red phosphorus as the flame retardant. The addition amount of magnesium hydroxide is preferably 40% by weight to 60% by weight based on the total weight of the coating resin, and the addition amount of red phosphorus is preferably about 0.5% to 8% by weight.

Various pigments such as carbon black as a coloring agent, calcium carbonate, titanium oxide as an inorganic filler,
Addition of silicic acid or the like is also possible. The plastic cable coated cable resin has been described above. The plastic optical fiber will now be described. The plastic optical fiber in the present invention is a step index type plastic optical fiber having a core and a sheath, a multi-core plastic optical fiber, or a refractive index distribution type plastic optical fiber. A step index type plastic optical fiber is widely used. For this, the core resin is, for example, a methyl methacrylate homopolymer or a copolymer containing 50% by weight or more of methyl methacrylate. Methyl acrylate, ethyl acrylate, acrylates such as butyl acrylate, ethyl methacrylate, propyl methacrylate, methacrylates such as cyclohexyl methacrylate, maleimides such as isopropyl maleimide, acrylic acid, methacrylic acid, There are styrene and the like, and one or more of them can be appropriately selected and copolymerized. As other preferable resins, styrene resins can be used. For example, a styrene homopolymer or a styrene-methyl methacrylate copolymer is used.
As other preferable resins, polycarbonate resins can be used. Polycarbonate resins have high heat resistance and low hygroscopicity. Also, Amorofaspole olefin resin can be used. Resins with trade names such as "Zeonex" manufactured by Zeon Corporation.

As the sheath resin, when the core resin is a methyl methacrylate resin, a resin containing a fluoroalkyl methacrylate, a vinylidene fluoride resin, or a mixture of a vinylidene fluoride resin and a methacrylate resin is used. Such as alloys. In particular, for communication applications, fluoroalkyl methacrylate resins are preferred because they have no crystallinity and do not change in loss at high temperatures. Fluoroalkyl methacrylate
Is a compound of the following formula:

[0016]

Embedded image

N = 1, 2; Integers from m = 1 to 11 X = H, F At least one kind of the fluoroalkyl methacrylate monomer represented by these, and another copolymerizable fluoroalkyl acrylate or It is a copolymer with alkyl methacrylate or alkyl acrylate. More specifically, as a fluoroalkyl methacrylate,
Trifluoroethyl methacrylate, tetrafluoropropyl methacrylate, pentafluoropropyl methacrylate, heptadecafluorodecyl methacrylate,
Examples include octafluoropropentyl methacrylate, and examples of fluorinated acrylate monomers include trifluoroethyl acrylate, tetrafluoropropyl acrylate, and octafluoropentyl acrylate. In addition to these fluorine-based monomers, methacrylate monomers such as methyl methacrylate and ethyl methacrylate and methyl acrylate as high refractive index components.
And copolymers in various combinations with acrylate monomers such as acrylate, ethyl acrylate and butyl acrylate.

Such a plastic optical fiber bare wire is coated with the coating resin of the present invention to form a plastic optical fiber cable. For example, when the core resin is a methyl methacrylate resin, the thermal deformation temperature of the resin is low. Care must be taken not to increase the transmission loss of the plastic optical fiber by coating the plastic optical fiber so as not to apply a thermal load as much as possible. However, since the molding temperature of the coating resin of the present invention ranges from about 170 ° C. to 230 ° C., it is necessary to perform a primary coating with a low thermal load on the bare plastic optical fiber before coating a thicker layer outside the primary coating. Can also. The coating of the inner layer may be a coating of polyethylene resin, a coating resin of the present invention, or a coating of vinylidene fluoride resin or nylon 12.

The plastic optical fiber cable of the present invention is used for personal computers, audiovisual equipment, exchanges, telephones, OA equipment, FA equipment and the like. Particularly flexible cables have a good touch to the touch. Ideal for familiar home appliances. It is also suitable as a curl code. Hereinafter, an embodiment will be described.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described by way of examples.

[0021]

Example 1 A core resin was a polymethyl methacrylate resin,
A plastic optical fiber manufactured using a copolymer resin of fluoroalkyl methacrylate and methyl methacrylate as the sheath and having a core diameter of 980 μm and a sheath outer diameter of 100
The following coating resin was coated on the 0 μm bare wire. The coating resin comprises the following components. Hydrogenated block copolymer Number average molecular weight 210,000, molecular weight distribution 1.2, bound styrene content 35% by weight, 1,2-vinyl bond content of polybutadiene portion before hydrogenation 36% by weight, hydrogenation rate of polybutadiene portion 99 % Styrene / butadiene block copolymer hydrogenated block copolymer.
No. 4 synthesized by the method described in JP-A No. 0147
0 parts by weight. Hydrogenated block copolymer Number average molecular weight 65,000, molecular weight distribution 1.13, bound styrene amount 23% by weight, 1,2-vinyl bond amount in polybutadiene portion before hydrogenation 36% by weight, hydrogenation rate in polybutadiene portion 99 % Styrene / butadiene block copolymer hydrogenated block copolymer.
No. 6 synthesized by the method described in JP-A No. 0147
0 parts by weight. Polypropylene resin mixture 60 parts by weight of a polypropylene mixture, manufactured by Montell Corporation, manufactured by Cataloy Adflex KS-084P, having a melt flow index of 30 g / 10 min, a flexural modulus of 108 MPa and a Shore D hardness of 44. Hydrocarbon oil As a hydrocarbon oil, 40 parts by weight of Diana process oil PW-380, manufactured by Idemitsu Kosan Co., Ltd. Polyolefin-based resin A polyolefin-based resin made of JPO, SHIO ALLOMER 511, melt flow index 15 g / 10 min, and a flexural modulus of 1400 MPa.
Resin consisting of cm ² and elongation of 760%.

These blending materials are mixed to the blending number of parts,
After blending with a Henschel mixer, the mixture was melt-kneaded at 220 ° C. with a twin-screw extruder to obtain coated resin pellets. A flat flat plate is formed using the pellets, the flat plate is placed horizontally, a cotton cloth to which a load of 40 g / cm ² is applied is placed and reciprocated 200 times, and the glossiness of the friction surface is measured according to JISK.
The gloss retention was measured before and after friction by the method of 7105. The value was 84%, and it was confirmed that the coating resin had excellent scratch resistance.

The coating resin was introduced into a coating extruder equipped with a cross die head, and a plastic optical fiber bare wire was coated at a molding temperature of 210 ° C. to a thickness of 0.6 mm to obtain a cable. The transmission loss in the plastic optical fiber cable was 150 dB / km for 650 nm monochromatic light. When this cable was left at 85 ° C. for 1000 hours, the transmission loss was stable at 155 dB / km.

[0024]

Example 2 The core resin was a polymethyl methacrylate resin,
A plastic optical fiber made of a copolymer of vinylidene fluoride 80 mol% and tetrafluoroethylene 20 mol% as a sheath, having a core diameter of 980 μm and a sheath outer diameter of 1000
1. μm bare wire, and polyethylene on top
A cable coated to an outer diameter of 2 mm was coated with the following coating resin. That is, 100 parts by weight of the hydrogenated block copolymer shown in Example 1, 100 parts by weight of the polypropylene mixture, and 100 parts by weight of the hydrocarbon oil were mixed as the coating resin in the number of parts by weight, and blended with a Henschel mixer. After that, the mixture was melt-kneaded at 220 ° C. using a twin-screw extruder to obtain coated resin pellets. The resin has a melt flow index of 15 g / 10 minutes and a hardness of JISA 42.
, Tensile strength 100 kgf / cm ² and elongation 950%.

This coating resin was also subjected to a friction test in the same manner as in Example 1, and the gloss retention was examined.
And had excellent scratch resistance. The temperature of the cable coating was 230 ° C. A soft touch cable with a glossy appearance and an elastic surface was obtained. The transmission loss of this plastic optical fiber cable was 140 dB / km with 650 nm monochromatic light. When this cable was left at 70 ° C. for 1000 hours, the transmission loss was stable at 160 dB / km.

[0026]

The optical fiber cable having the coating material of the present invention has excellent scratch resistance, flexibility and the like.

Claims (1)

[Claims] (A) It comprises two or more polymer blocks A mainly composed of styrene and one or more polymer blocks B obtained by hydrogenating a polymer mainly composed of a conjugated diene compound, 100% by weight of one or more of block copolymers having a number average molecular weight of 30,000 to 400,000 constituting a total amount of the polymer block A of 10 to 50% by weight (b) a homopolymer of polypropylene or 85% by weight of propylene A propylene-α-olefin copolymer containing the above, or a propylene-ethylene copolymer containing 85% or more of propylene, and a propylene-ethylene copolymer containing 75% or less of propylene or propylene containing 75% or less of propylene -A mixture comprising an ethylene-α-olefin copolymer, wherein the content of the ethylene component in the mixture is 15%. 5 to 900 parts by weight of a polypropylene resin mixture which is 60% by weight (c) 0 to 200 parts by weight of a hydrocarbon oil (d) A coating layer comprising a resin composition comprising 0 to 150 parts by weight of a polyolefin resin other than (b) Having plastic optical fiber cable.