JP2000039542A - Plastic optical fiber cable - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a coating material excellent in scuffing resistance, flexibility, weather resistance, heat resistance, low temp. characteristics, coating ability, etc., and excellent also in flame resistance by combining a specified olefinic elastomer, a block copolymer, a propylene polymer and an oil for rubber in a specified ratio. SOLUTION: A mixture of 100 pts.wt. olefinic elastomer, 0-100 pts.wt. block copolymer, 5-200 pts.wt. propylene polymer and 5-150 pts.wt. oil for rubber is mixed with a radical initiator and the resultant thermoplastic elastomer compsn. is used as a coating resin for outer coating. The olefinic elastomer consists of ethylene and a 6-12C α-olefin, the proportion of the α-olefin in copolymn. is 20-60 wt.% and the elastomer has 0.8-0.9 g/cm3 density and is produced using a metallocene catalyst. The block copolymer consists of polymer blocks A based on a vinyl arom. compd. and polymer blocks B based on a conjugated diene compd.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[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. It has been occupied as a mainstream cable such as an audio cable and an OA cable.

[0003]

However, in recent years, it has been found that harmful dioxins are generated when organic chlorine compounds such as polyvinyl chloride are burned by inappropriate facilities at the stage of waste incineration. Polyvinyl chloride resin has begun to be shunned. 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 has excellent scratch resistance, excellent flexibility, excellent weather resistance, excellent heat resistance, excellent low temperature properties, excellent coating processability, and in some cases, flame retardancy. It is intended to provide a plastic optical fiber cable made of a coating material excellent in quality.

[0004]

That is, the present invention provides (1)
It consists of ethylene and an α-olefin having 6 to 12 carbon atoms, and the copolymerization ratio of the α-olefin is 20 to 60% by weight.
Having a density in the range of 0.8 to 0.9 g / cm ³ , 100 parts by weight of an olefin-based elastomer produced by using a metallocene-based catalyst, and (2) mainly containing at least one vinyl aromatic compound. A block copolymer comprising a polymer block A and a polymer block B mainly composed of at least one conjugated diene compound, or a block copolymer 0 to 1 obtained by hydrogenating this block copolymer.
A mixture comprising 00 parts by weight, (3) 5-200 parts by weight of a propylene-based polymer, and (4) 5-250 parts by weight of a rubber oil is crosslinked with a radical initiator or a radical initiator and a crosslinking aid. A plastic optical fiber cable in which a thermoplastic elastomer composition is externally coated as a coating resin.
A thermoplastic elastomer composition, a block copolymer comprising at least one polymer block A mainly composed of a vinyl aromatic compound and at least one polymer block B mainly composed of a conjugated diene compound, or This is a plastic optical fiber cable in which a thermoplastic elastomer composition obtained by mixing a block copolymer obtained by hydrogenating this block copolymer is coated as a coating resin.

(Olefin-based elastomer) The olefin-based elastomer which is a main component of the thermoplastic elastomer composition of the present invention is a copolymer comprising ethylene and at least one or more α-olefins having 6 to 12 carbon atoms. It has a specific copolymerization ratio, a specific density, and a specific molecular weight distribution.

As the α-olefin having 6 to 12 carbon atoms, for example, hexene-1,4-methylpentene-1,
Heptene-1, octene-1, nonene-1, decene-
1, undecene-1, dodecene-1 and the like. Among them, hexene-1, 4-methylpentene-1 and octene-1 are preferred, and octene-1 is particularly preferred.
Octene-1 is excellent in softening effect even in a small amount, and the obtained copolymer is excellent in mechanical strength.

The olefin elastomer used in the present invention is preferably produced using a known metallocene catalyst.

The metallocene catalyst comprises a cyclopentadienyl derivative of a group IV metal such as titanium or zirconium and a co-catalyst, and is not only highly active as a polymerization catalyst but also compared with a conventional catalyst such as a Ziegler catalyst. do it,
The molecular weight distribution of the obtained polymer is narrow, and the distribution of the comonomer α-olefin having 6 to 12 carbon atoms in the copolymer is uniform.

Therefore, olefin elastomers produced with metallocene catalysts differ greatly in polymer properties compared to conventional ones using Ziegler catalysts and the like.

The characteristics of an olefin elastomer composed of ethylene and an α-olefin using a metallocene polymerization catalyst are listed below. Since the polymerization catalyst has high activity, the composition of the comonomer α-olefin can be greatly increased as compared with the conventional one, and an elastomeric polymer having high flexibility can be obtained even without a plasticizer. 2. Uniform distribution of comonomer compared to Ziegler-based polymer; 3. Extremely sharp molecular weight distribution, extremely low molecular weight components, excellent mechanical strength and processability, and high quality compared to Ziegler polymers. Despite the sharp molecular weight distribution, when a long-chain branch is introduced, the melt index (I10) at 190 ° C./10 kgf specified by ASTM D1238 and the melt index (I2) at 190 ° C./2.16 kgf are obtained. 4. The ratio (I10 / I2) is large, and the processing characteristics are excellent. 5. It does not contain a diene component and has excellent resistance to environmental degradation. Even if the copolymerization ratio of the α-olefin is high, blocking hardly occurs, and a pellet form is possible.

In the case of an olefin elastomer which is a copolymer of ethylene and an α-olefin with a Ziegler catalyst, the above-mentioned melt index ratio (I10 / I2) and the molecular weight distribution show a substantially linear proportional relationship. The molecular weight distribution tends to increase with the increase. The molecular weight distribution is about 3 to 10.

On the other hand, in the case of an olefin polymer using a metallocene catalyst, the molecular weight distribution becomes a sharp value of less than 3.0 and the amount of low molecular weight components is extremely small regardless of the value of the melt index ratio. For this reason, workability is extremely excellent.

The molecular weight distribution (Mw / Mn) of these olefinic elastomers is calculated by GPC. GP
The C apparatus and the measuring method are not particularly limited, but the present inventors used the following apparatus and measuring method.

[0014] 1. Equipment Waters 150C GPC 2. 2. One column SHOdex AT-807S 1 Tosoh TSK-GEL GMH-H6 2 3 in total Solvent 1,2,4-trichlorobenzene 4. Measurement temperature 140 ° C 5. Standard substance Polystyrene The olefin elastomer used in the present invention is α
The copolymerization ratio of the olefin is from 20 to 60% by weight;
At this time, the hardness of the elastomer is low and the amount of oil that can be retained is large, so that a composition that is difficult to bleed oil can be obtained.

If the amount is less than 20% by weight, it is difficult to obtain a composition having a high hardness of the copolymer and a low hardness, the oil holding capacity is insufficient, and the problem of oil bleeding occurs.
On the other hand, if the content is 60% by weight or more, the mechanical strength of the copolymer is greatly reduced, and the tensile strength and the like of the composition are greatly reduced, which is not desirable.

By using such an elastomer, it is possible to obtain a flexible thermoplastic elastomer composition having a surface hardness A type specified in ASTM D2240 of 90 or less.

The density ranges from 0.8 to 0.9 g / cm ³ . By using an olefin elastomer having a density in this range, a thermoplastic elastomer composition having excellent flexibility and low hardness can be obtained.
In particular, copolymerization ratio c (% by weight) and density d (g / cm ³ )
When the following formula (a) is satisfied, -0.0026 × c + 0.9200 ≦ d ≦ −0.0026 × c + 0.9400 (a) The elastomer has an excellent balance between mechanical strength and physical properties of hardness. Is more preferable. If the density d is lower than this range, the mechanical strength is insufficient, and if the density d is higher than this range, oil bleed tends to occur, which is not preferable.

The olefin elastomer used in the present invention preferably has a long-chain branch. The presence of the long-chain branch enables the density to be lower than the ratio (% by weight) of the copolymerized α-olefin without lowering the mechanical strength.
An elastomer having low hardness and high strength can be obtained. Examples of the olefin elastomer having a long chain branch include U
It is described in SP5278272 and the like.

The olefin elastomer preferably has a DSC melting point peak at room temperature or higher. When it has a melting point peak, the form is stable in the temperature range below the melting point, the handleability is excellent, and the stickiness is small.

The melt index of the olefin elastomer used in the present invention is 0.01 to 10%.
Those having a range of 0 g / 10 minutes (190 ° C., 2.16 kg load) are preferably used, and more preferably 0.2 to 10 minutes.
g / 10 minutes. If it exceeds 100 g / 10 minutes, the crosslinking property of the thermoplastic elastomer composition will be insufficient, and if it is less than 0.01 g / 10 minutes, the fluidity will be poor and the processability will be undesirably reduced.

The olefin-based elastomer having the above specific structure has surprisingly excellent radical crosslinkability comparable to conventional EPDM, and is a crosslinkable elastomer component of a thermoplastic elastomer composition by dynamic crosslinking. Is the most suitable polymer. Dynamic cross-linking is a processing method in which a cross-linking reaction is performed in a short time in a kneading machine, and a cross-linking time (Tc90), which is an index of the cross-linking speed, is 400 seconds or less, preferably a copolymer having 300 seconds or less, More preferably, the time is 200 seconds or less. Here, the crosslinking time (Tc90) is defined as the value obtained by adding 1.0 part by weight of dicumyl peroxide to the elastomer as peroxide.
When the vulcanization characteristics were measured with a rheometer at 70 ° C,
This is the time required to reach 90% of the maximum degree of crosslinking (viscosity). In particular, when octene-1 is used as the α-olefin and the copolymerization ratio is 20 to 40% by weight, the crosslinking time (Tc90) is preferably 200 seconds or less.

The olefin elastomer used in the present invention may be a mixture of a plurality of types.
It is possible to further improve the workability.

[0023] Ethylene produced by such a metallocene catalyst and at least one or more carbon atoms having 6 to 1 carbon atoms.
As the olefin-based elastomer composed of the α-olefin No. 2, products such as "Engage" of DuPont Dow Elastomers are known.

(Block copolymer) A block copolymer comprising at least one polymer block A mainly composed of a vinyl aromatic compound and at least one polymer block B mainly composed of a conjugated diene compound, or By adding a block copolymer obtained by hydrogenating this block copolymer, it is possible to drastically improve oil retention, which is desirable.

The block copolymer of the present invention comprises, for example, A
-B, ABA, ABAB, ABAB-
A, BABAB, (AB) 4Si, (BA)
-B) 4Si, (BAB) 4Sn, etc.

The polymer block mainly composed of a vinyl aromatic compound refers to a copolymer block of a vinyl aromatic compound containing 50% by weight or more of a vinyl aromatic compound and a conjugated diene compound and / or a single polymer of a vinyl aromatic compound. Shows the coalescing block.

The polymer block mainly composed of a conjugated diene compound refers to a copolymer block of a conjugated diene compound containing at least 50% by weight of a conjugated diene compound and a vinyl aromatic compound and / or a homopolymer block of a conjugated diene compound. Show.

As the vinyl aromatic compound constituting the block copolymer, styrene, methylstyrene, 1,3-
One or more of dimethylstyrene, p-tert-butylstyrene and the like can be used. Among them, styrene is preferred.

As the conjugated diene compound constituting the block copolymer, one or more of butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene and the like can be used. . Among them, butadiene, isoprene and a combination thereof are preferred.

The method for producing these block copolymers may be any known method, for example, using a polymerization initiator such as an organolithium compound in a hydrocarbon solvent to block a vinyl aromatic compound and a conjugated diene compound. A block copolymer obtained by hydrogenation, which is a polymerization method, can be obtained by subjecting the block copolymer to a hydrogenation reaction. The method of the hydrogenation reaction may be any known method, for example, hydrogenation can be performed in an inert solvent in the presence of a hydrogenation catalyst. The reaction conditions for hydrogenation are selected such that at least 80%, preferably 90% or more, of the conjugated diene compound is hydrogenated, while less than 20%, preferably less than 10%, of the vinyl aromatic compound is hydrogenated. Is done.

The number average molecular weight of the block copolymer having the above structure is 20,000 to 300,000, preferably 30.
000 to 200,000.

In the present invention, the addition of the block copolymer may be carried out simultaneously with the dynamic crosslinking, or may be carried out after the completion of the dynamic crosslinking. As a result, it is a major feature that the characteristics as an elastomer are increased, and the ability to hold a large amount of rubber oil is increased, so that a low hardness composition can be obtained. This allows
As if you had the conventional soft PVC resin,
A cable with a profound feeling and good touch with an A hardness of around 60 is possible.

The block copolymer is used in a composition ratio of 0 to 100 parts by weight. If it exceeds 100 parts by weight, the heat resistance of the composition decreases, which is not desirable.

In addition, it is preferable to add a low molecular weight ethylene polymer having a number average molecular weight of 20,000 or less.
This is desirable because the molding processability of the composition, the surface texture of the molded product, and the like are remarkably improved.

The low molecular weight ethylene polymer used in the present invention is a polymer having a number average molecular weight of 20,000 or less. As the type of the polymer, for example, polyethylene,
Ethylene-α olefin copolymer, ethylene-vinyl ester copolymer such as ethylene-vinyl acetate copolymer, ethylene-unsaturated carboxylic acid ester copolymer such as ethylene-ethyl acrylate copolymer, ethylene-vinyl alcohol copolymer Polymers and the like. Among them, an ethylene-α-olefin copolymer has excellent flexibility and is suitable without impairing the physical properties of the elastomer composition. Here, the α-olefin preferably has 3 to 12 carbon atoms.

The number average molecular weight is calculated by GPC.
The same GPC apparatus and measuring method as those used in the measurement of the molecular weight distribution of the olefin-based elastomer described above were used. The value obtained under these conditions is expressed in terms of the polyethylene conversion coefficient (0.4
Multiplied by 3) to obtain the number average molecular weight of the present invention.

Such an ethylene polymer having a low molecular weight is well compatible with an olefin elastomer, and does not significantly decrease fluidity under the dynamic crosslinking reaction environment of the present invention. The degree of crosslinking of the system elastomer can be adjusted. That is, by changing the amount of the low molecular weight ethylene-based polymer in the range of 0 to 100 parts by weight, the degree of crosslinking of the olefin-based elastomer is 30 to 80 parts by weight based on the weight of the olefin-based elastomer used.
% Can be adjusted. If the amount of the low molecular weight ethylene polymer exceeds 100 parts by weight, the mechanical strength of the elastomer composition is undesirably reduced.

(Propylene Polymer) Specific examples of the propylene polymer used in the present invention include homo-isotactic polypropylene, propylene and ethylene, butene-1, pentene-1, hexene-1 and the like. And isotactic copolymers (including blocks and random) with other α-olefins.

At least one selected from these polymers
More than one polymer is used in a composition ratio of 5 to 200 parts by weight. Preferably it is 20 to 100 parts by weight. If the amount is less than 5 parts by weight, the fluidity and processability of the composition are reduced. If the amount is more than 200 parts by weight, the flexibility of the composition is insufficient, which is not desirable as a cable covering material.

The propylene polymer used in the present invention has a melt index of 0.1 to 100 g / 1.
Those in the range of 0 minutes (230 ° C., 2.16 kg load) are preferably used. If it exceeds 100 g / 10 minutes, the heat resistance and mechanical strength of the thermoplastic elastomer composition will be insufficient, and if it is less than 0.1 g / 10 minutes, the fluidity will be poor and the moldability will be reduced, which is not desirable. .

(Rubber Oil) The rubber oil used in the present invention is preferably a paraffinic or naphthenic process oil. These are used in an amount of 5 to 250 parts by weight for adjusting the hardness and flexibility of the composition. Preferably it is 10 to 150 parts by weight. If the amount is less than 5 parts by weight, flexibility and workability are insufficient, and if it exceeds 250 parts by weight, oil bleeding becomes remarkable, which is not desirable.

The thermoplastic elastomer composition provided by the present invention is obtained by combining the above-described specific olefin-based elastomer, block copolymer, propylene-based polymer, and rubber oil in a specific composition ratio. The balance between mechanical strength, flexibility and workability is improved, and it can be preferably used.

The thermoplastic elastomer composition provided by the present invention requires that the composition be partially or completely crosslinked with a radical initiator such as an organic peroxide or a radical initiator and a crosslinking assistant. It is. Thereby, it becomes possible to further improve the wear resistance, mechanical strength, heat resistance, and the like.

Here, specific examples of the radical initiator preferably used include 1,1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane,
1,1-bis (t-hexylperoxy) -3,3,5
-Trimethylcyclohexane, 1,1-bis (t-hexylperoxy) cyclohexane, 1,1-bis (t-
Butylperoxy) cyclododecane, 1,1-bis (t
-Butylperoxy) cyclohexane, 2,2-bis (t-butylperoxy) octane, n-butyl-4,
Peroxy ketals such as 4-bis (t-butylperoxy) butane and n-butyl-4,4-bis (t-butylperoxy) valerate; di-t-butyl peroxide, dicumyl peroxide, t -Butylcumyl peroxide, α, α′-bis (t-butylperoxy-m
-Isopropyl) benzene, α, α'-bis (t-butylperoxy) diisopropylbenzene, 2,5-dimethyl-2,5-bis (t-butylperoxy) hexane and 2,5-dimethyl-2,5 Dialkyl peroxides such as -bis (t-butylperoxy) hexyne-3; acetyl peroxide, isobutyryl peroxide, octanoyl peroxide, decanoyl peroxide, lauroyl peroxide, 3,5,5-trimethylhexa Diacyl peroxides such as noyl peroxide, benzoyl peroxide, 2,4-dichlorobenzoyl peroxide and m-trioyl peroxide; t-butylperoxyacetate, t
-Butylperoxyisobutyrate, t-butylperoxy-2-ethylhexanoate, t-butylperoxylaurate, t-butylperoxybenzoate,
Di-t-butylperoxyisophthalate, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, t-butylperoxymaleic acid, t-butylperoxyisopropyl carbonate, and cumylperoxyoctate Peroxyesters; and
Hydrogens such as t-butyl hydroperoxide, cumene hydroperoxide, diisopropylbenzene hydroperoxide, 2,5-dimethylhexane-2,5-dihydroperoxide and 1,1,3,3-tetramethylbutyl peroxide Peroxides can be mentioned.

Among these compounds, 1,1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane, di-t-butyl peroxide, dicumyl peroxide, 2,5-dimethyl -2,5-bis (t-butylperoxy) hexane and 2,5-dimethyl-2,5-bis (t-butylperoxy) hexyne-3 are preferred.

These radical initiators are used in an amount of 0.02 to 3 parts by weight based on 100 parts by weight of the olefin elastomer.
Preferably it is used in an amount of 0.05 to 1 part by weight. 0.
If the amount is less than 02 parts by weight, the crosslinking is insufficient, and if it exceeds 3 parts by weight, the physical properties of the composition are not improved, which is not preferable.

Further, as a crosslinking aid, divinylbenzene, triallyl isocyanurate, triallyl cyanurate, diacetone diacrylamide, polyethylene glycol diacrylate, polyethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, trimethylolpropane triacrylate , Ethylene glycol dimethacrylate, triethylene glycol dimethacrylate, diethylene glycol dimethacrylate, diisopropenylbenzene, P-quinone dioxime, P, P'-dibenzoylquinone dioxime, phenylmaleimide, allyl methacrylate, N, N'-
m-phenylene bismaleimide, diallyl phthalate,
Tetraallyloxyethane, 1,2-polybutadiene and the like are preferably used. These crosslinking aids may be used in combination of two or more.

These crosslinking assistants are used in an amount of 0.1 to 5 parts by weight, preferably 0.5 to 2 parts by weight, based on 100 parts by weight of the olefin elastomer. If the amount is less than 0.1 part by weight, crosslinking is insufficient, and if it exceeds 5 parts by weight, the physical properties of the composition are not improved, and an excessive amount of a crosslinking aid remains, which is not preferable.

The hardness of the thermoplastic elastomer composition provided by the present invention is desirably 50 to 90 for the surface hardness A type defined by ASTM D2240. If it is less than 50, stickiness becomes a problem, and if it exceeds 90, similar materials can be easily procured. Preferred hardness is 55-69,
A composition having a hardness in this range is a coating material having a very heavy feel and excellent touch, and is most suitable for audio cables, home appliance cables, OA cables, and the like.

In addition, the following polymers may be added to the composition of the present invention to such an extent that the characteristics are not impaired. Specifically, polyethylene, polybutene, polyisobutene,
Ethylene-vinyl ester copolymers such as ethylene-vinyl acetate copolymers, ethylene-unsaturated carboxylic acid ester copolymers such as ethylene-ethyl acrylate copolymers,
And ethylene-vinyl alcohol copolymer.

In the present invention, it is possible to add a flame retardant such as magnesium hydroxide, aluminum hydroxide, red phosphorus, or a phosphorus compound to the thermoplastic elastomer composition to carry out safe flame retarding treatment. it can. It is effective to add about 40 to 80% by weight of magnesium hydroxide. In addition, other additives, for example, organic and inorganic pigments, heat stabilizers, antioxidants, ultraviolet absorbers, light stabilizers,
Flame retardants, silicone oils, antiblocking agents, foaming agents, antistatic agents, antibacterial agents, and rodents are also used.

For the production of the thermoplastic elastomer composition of the present invention, general resin compositions and general Banner mixers, kneaders, single-screw extruders, twin-screw extruders and the like used for the production of elastomer compositions are used. It is possible to adopt a method.

However, among them, a twin-screw extruder is preferably used. The twin-screw extruder uniformly and finely disperses the olefin-based elastomer, the propylene-based polymer, and the block copolymer, and further adds another component to cause a crosslinking reaction. Is more suitable for continuous production.

The form of the olefin-based elastomer, propylene-based polymer or block copolymer to be used is preferably a finely divided form such as pellets, powders and crumbs.

The thermoplastic elastomer composition of the present invention comprises:
As a specific example, it can be manufactured through the following processing steps.

That is, the olefin-based elastomer, the propylene-based polymer, and the block copolymer are well mixed and then charged into a hopper of an extruder. The radical initiator and the crosslinking assistant may be added from the beginning together with the olefin-based elastomer, the block copolymer, and the propylene-based polymer,
You may add from the middle of an extruder. The oil may be added from the beginning of the extruder or from the middle, or may be added separately from the beginning and the middle. The olefin-based elastomer, the propylene-based polymer, and the block copolymer may be partially added in the middle of the extruder. When heated and melted and kneaded in an extruder, the elastomer and the radical initiator and the crosslinking auxiliary undergo a crosslinking reaction, and the crosslinking reaction and kneading dispersion are sufficiently performed by further adding and melting oil and kneading. Then remove from the extruder. Pellets can be obtained to obtain pellets of the thermoplastic elastomer composition of the present invention.

The degree of crosslinking is defined as a measure of the crosslinkability of the composition. 0.5 g of the thermoplastic elastomer composition of the present invention
Is refluxed for 4 hours in 200 ml of xylene. The solution is filtered through a filter paper for quantification, the residue on the filter paper is vacuum-dried, quantified, and calculated as a ratio (%) of the weight of the residue to the weight of the olefin-based elastomer in the composition.

The crosslinking degree of the thermoplastic elastomer composition of the present invention is desirably 30% or more. If it is less than 30%, crosslinking is insufficient, and heat resistance such as compression set and physical properties such as rebound resilience are reduced.

The plastic optical fiber 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 a trade name such as "Zeonex" manufactured by Zeon Corporation. When the core resin is a methyl methacrylate resin, the sheath resin may be a resin containing a fluoroalkyl methacrylate, a vinylidene fluoride resin, or an alloy obtained by mixing a vinylidene fluoride resin with a methacrylate resin. In particular, fluoroalkyl methacrylate resins having no crystallinity and having no change in loss at high temperatures are preferred for communication applications. As a fluoroalkyl methacrylate is a compound of the following formula, n = 1, an integer from m = 1 to 11 X = H, F One or more of the fluoroalkyl methacrylate monomers represented by these and other copolymerizable fluoroalkyl acrylate, alkyl methacrylate or alkyl acrylate It is a copolymer. More specifically, examples of the fluoroalkyl methacrylate include:
Trifluoroethyl methacrylate, tetrafluoropropyl methacrylate, pentafluoropropyl methacrylate, heptadecafluorodecyl methacrylate,
Examples include octafluoropropentyl methacrylate, and examples of the fluorinated acrylate monomer include trifluoroethyl acrylate, tetrafluoropropyl acrylate, and octafluoropentyl acrylate. And, in addition to these fluorine-based monomers, as a high refractive index component, methacrylate monomers such as methyl methacrylate and ethyl methacrylate and copolymers by various combinations with acrylate monomers such as methyl acrylate, ethyl acrylate, and butyl acrylate are cited. Can be

A plastic optical fiber cable is obtained by coating such a plastic optical fiber bare wire with the coating resin of the present invention. 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, the flexible cable has a good touch to the touch. Ideal for home appliance use. It is also suitable as a curl code. Hereinafter, an embodiment will be described.

[0062]

EXAMPLE A plastic optical fiber manufactured using a polymethyl methacrylate resin as a core resin and a copolymer resin of fluoroalkyl methacrylate and methyl methacrylate as a sheath, having a core diameter of 980 μm and a sheath outer diameter of 1000.
The following coating resin was coated on the μm bare wire.

Example 1 The coating resin was composed of the following components.

Component (1) Olefin elastomer 100 parts by weight of a copolymer of ethylene and octene-1 (Engage 8180 available from Dupont Dow Elastomers, polymerization catalyst: metallocene, α-olefin copolymerization ratio: 28) % By weight, density: 0.863 g / c
DSC, m ³ , Mw / Mn = 2.4, with long chain branching
Melt index (ASTM having melting point peak)
D1238) 0.5, hardness (ASTM D2240, type A) 65), crosslinking time (Tc90) 168 seconds) Component (2) Block copolymer AB composed of styrene block polymer A and butadiene block polymer B 50 weight parts of a block copolymer having a structure of -A and being hydrogenated (a styrene-butadiene block copolymer having a styrene content of 20 weight%, a number average molecular weight of 51,000, and a hydrogenation rate of a polybutadiene portion of 99%; Melt index (AST
M D1238) 12, hardness (ASTM D224)
0, Type A) 67) Component (3) Propylene Polymer 50 parts by weight of homo isotactic polypropylene (J-Aroma M16 manufactured by Nippon Polyolefin Co., Ltd.)
00, melt index 15) Component (4) Oil for rubber PW-38 manufactured by Idemitsu Kosan Co., Ltd. as a paraffinic oil
0 as 100 parts by weight 2,5-dimethyl-2,5-bis (t-butylperoxy) hexane as a radical initiator 0.5 parts by weight perhexa 25B (manufactured by NOF CORPORATION) divinylbenzene as a crosslinking aid 1.0 part by weight was used.

These materials were kneaded and reacted at a temperature of 220 ° C. in a twin-screw extruder to obtain pellets. The hardness of this composition was 60 for surface hardness A type defined in ASTM D2240. The melt flow index of this composition was 1.5 at 230 ° C. under a load of 2.16 kg. 0.5% by weight of carbon black is added to the resin,
The coating resin was used.

The coating resin was introduced into a coating extruder equipped with a cross die head, and a cable was coated at a molding temperature of 210 ° C. The plastic optical fiber was coated with the composition of the present invention on a cable having a low-density polyethylene coating having an outer diameter of 2.2 mm on a bare wire of 1.0 mm. The coating temperature was 220 ° C., and the coating outer diameter was 4.
It was set to 0 mm. The obtained cable was elastic and the surface was fine and matte, and the cable was heavy and comfortable to touch. Transmission loss in plastic optical fiber cable is 140 dB / km for 650 nm monochromatic light
Met. When this cable was left at 85 ° C. for 1000 hours, the transmission loss was stable at 140 dB / km.

Example 2 Component (1) Olefin-based elastomer 100 parts by weight of a copolymer of ethylene and octene-1 (Engage 8100 available from Dupont Dow Elastomers, polymerization catalyst; metallocene-based, α-olefin copolymer Ratio: 24% by weight, Density: 0.870 g / c
m ³ , Mw / Mn = 2.3, DSC having a long chain branch
Melt index (ASTM having melting point peak)
D1238) 1.0, hardness (ASTM D2240, type A) 75), crosslinking time (Tc90) 315 seconds) Component (2) Block copolymer AB composed of styrene block polymer A and isoprene block polymer B -A structure, hydrogenated block copolymer 40 parts by weight (a styrene-isoprene block copolymer having a styrene content of 20 wt%, a number average molecular weight of 53,000, and a hydrogenation rate of the polyisoprene portion of 99%) , Melt index (AST
MD1238) 13, hardness (ASTM D224)
0, Type A) 66) Component (3) Propylene polymer 40 parts by weight of homo isotactic polypropylene (J-Aroma M16 manufactured by Nippon Polyolefin Co., Ltd.)
00, melt index 15) Component (4) Oil for rubber PW-38 manufactured by Idemitsu Kosan Co., Ltd. as a paraffinic oil
0 90 parts by weight 2,5-dimethyl-2,5-bis (t-butylperoxy) hexane 0.5 parts by weight perhexa 25B (manufactured by NOF CORPORATION) as a radical initiator divinylbenzene as a crosslinking aid 1.0 part by weight was used.

These materials were subjected to a kneading reaction at a temperature of 220 ° C. in a twin-screw extruder to obtain pellets. The hardness of this composition was 63 for surface hardness A type specified in ASTM D2240. The melt flow index of this composition was 1.6 at 230 ° C. and a load of 2.16 kg. 0.5% by weight of carbon black is added to the resin,
The coating resin was used.

A cable was made in the same manner as in Example 1. The obtained cable was elastic and the surface was fine and matte, and the cable was heavy and comfortable to touch. The transmission loss of the plastic optical fiber cable was 135 dB / km for 650 nm monochromatic light. Connect this cable to 8
Transmission loss when left at 5 ° C for 1000 hours is 135dB
/ Km.

[0070]

As described above, according to the present invention, a plastic optical fiber cable which is suitable as a coating resin for a plastic optical fiber cable and is coated with a coating resin which can be substituted for conventional polyvinyl chloride can be obtained.

Claims (3)

[Claims] (1) (1) It comprises ethylene and an α-olefin having 6 to 12 carbon atoms, the copolymerization ratio of the α-olefin is 20 to 60% by weight, and the density is 0.8 to 0.9 g /
in the range of cm ^3, mainly of olefin elastomer 100 parts by weight of the preparation (2) and at least one polymer block A composed mainly of a vinyl aromatic compound at least one conjugated diene compound using a metallocene catalyst Or a block copolymer obtained by hydrogenating this block copolymer. (3) 5-200 parts by weight of a propylene-based polymer (4) A plastic optical fiber cable in which a thermoplastic resin composition obtained by crosslinking a mixture of 5 to 250 parts by weight of rubber oil with a radical initiator or a radical initiator and a crosslinking aid is used as a coating resin. 2. The thermoplastic elastomer composition according to claim 1, wherein component (2) is 0, wherein at least one polymer block A mainly composed of a vinyl aromatic compound and at least one conjugated diene compound are added. A plastic light coated with a thermoplastic elastomer composition comprising a block copolymer comprising a main polymer block B or a block copolymer obtained by hydrogenating this block copolymer as a coating resin. Fiber cable. 3. The thermoplastic resin composition according to claim 1, wherein said thermoplastic elastomer composition having a surface hardness of A type defined in ASTM D2240 is 50 to 90 as a coating resin.
A plastic optical fiber cable as described.