JPS5918903A - Optical transmission cable - Google Patents

Abstract

PURPOSE:To obtain an optical transmission cable having excellent resistance to flexing by consisting a sleeve component of an org. polymer and making the peeling strength between a core component and the sleeve component higher than the specific peeling strength that the sleeve component and a jacket component possess. CONSTITUTION:A sleeve component is constituted of an org. polymer and the peeling strength between a core component and the sleeve component is made the same or higher than the peeling strength of the sleeve component and a jacket component and the peeling strength between the sleeve component and the jacket component is maintained at >=30 when tested with a cross cut test for peeling strength, in an optical transmission cable having a double structure of the core and the sleeve and an optical transmission cable thereof. A polymer prepd. by copolymerizing 30-99.95pts.wt. fluorinated alkyl methacrylate, 0- 70pts.wt. vinyl polymer that can be copolymerized therewith, and 0.05-30pts.wt. vinyl monomer that can form an independent hydrophilic polymer is advantageously used as the above-described sleeve component.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an optical transmission cable with excellent bending resistance. In a preferred embodiment, the present invention also relates to an optical transmission cable comprising a step-index optical transmission fiber and a jacket portion, the sheath component of which is a substantially transparent organic polymer having a lower refractive index than the core component.

Conventionally, optical cape 71/ which uses optical transmission fiber with core-sheath double X & has a weak peeling strength between the core and sheath and between the sheath and jacket, and the optical transmission performance deteriorates when the optical cable is repeatedly bent and bent. has decreased significantly, and improvements have been desired at a practical level.

The inventors of the present invention have conducted research aimed at improving the bending resistance of optical cables and completing optical transmission cables that are practically mechanically durable, have high durability, and are reliable. We discovered that the adhesion between the core and sheath components and the adhesion between the sheath and jacket components are correlated with the bending resistance of optical cables.We then succeeded in improving the sheath component polymer and, more importantly, the jacket component. , reached the 6th day of Thursday.

That is, the present invention provides an optical transmission cable consisting of an optical transmission fiber having a core-sheath double-groove structure and a jacket portion covering the optical transmission fiber (herein, the sheath component is made of an organic polymer, and the core component and the sheath component are The peeling strength between the sheath component and the jacket component is substantially the same as or greater than the peeling strength between the sheath component and the jacket component, and the peeling strength between the sheath component and the jacket component has been tested using the cross-cut peeling 9fW test described below. Must be 3θ or more′? i: Characteristic bending resistance [This is related to the extremely poor optical transmission cable G.

The cross-cutting test for non-invention is JIS.
! It is a test method based on QOO, and the peeling strength is measured by straining as follows: Consists of core component or jacket component. SO on a 2-3 nm thick sheet
A film of the combined sheath component with a thickness of μσ is llli degree, 2
00C 1 hour 70 seconds, main power 5 IC 9/cJ heating breath G reamed - cut the laminate film vertically and horizontally with a razor in a square shape for 21 seconds, cut into 100 pieces of 211 m square. Create a grid. After thoroughly rubbing the tape on all the squares, remove the tape at once. When the peeling strength is weak, the sheath component film will stick to the cellophane tape and separate from the original sheet. The remaining squares on the laminated sheet without being peeled off! Let I be the peeling strength. If the peeling strength is sufficiently high, the squares will not be peeled off and the peeling strength will be /θ0.

Although this test method is a very simple method, it has an extremely good correlation with the bending resistance of optical transmission cables.

The core components of the optical transmission fiber G of the present invention include substantially transparent organic polymers such as methyl methacrylate polymers, styrene polymers, and polycarbonates, and known components for optical fibers such as quartz and multicomponent glass. is used.

tli rfl < , a combination of vinyl monomers 0 to 06 that can be copolymerized with this is advantageous (this is used, but it is preferable to use the following copolymer: /) methacrylic acid 2.212-trifluoroethyl 10-999
5 parts by weight, vinyl II-mer θ~30 that can be copolymerized with this
* Electric part, vinyl ridge body O that can form a hydrophilic homopolymer
A fluoroalkyl methacrylate copolymer characterized by copolymerizing a mixture consisting of θS ~ 30 moieties, 2) methacrylic acid, 2. +2.3. ．． 3. 60 to 9995 parts by weight of 3-pentafluoropropyl, vine vinyl #excipient o-1Io heavy paper copolymerized with this, vine vinyl monomer O,OS to 3θ Kurama that forms a hydrophilic homopolymer 3) a fluoroalkyl methacrylate copolymer characterized by copolymerizing a mixture consisting of a mixture of methacrylic acid, λ, 313-tetrafluoropropyl 70 and q'zqs; A fluoroalkyl methacrylate copolymer characterized by copolymerizing a mixture consisting of a single vinyl body OθS to 30 body parts and a vinyl body body OθS to 30 body parts capable of forming a hydrophilic homopolymer. .

Examples of the citrus monomer copolymerized with the fluoroalkyl methacrylic acid include methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, tθrt-butyl methacrylate, lauryl methacrylate, nonyl methacrylate, methyl acrylate, butyl acrylate, Examples include two-ethylhexyl acrylate, styrene, and α-methylstyrene, but methacrylate is preferable due to its copolymer properties.

Examples of vinyl monomers that can form hydrophilic ridge polymers include those having the following properties.

Single ethylenic mono- or dicarboxylic acids such as G, acrylic acid, methacrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid, glutaconic acid, 3-methylglutaconic acid, muconic acid, dihydromuconic acid, methylenemalonic acid , citraconic acid, mesaconic acid, methylene glutaconic acid, etc., but methacrylic acid and acrylic acid are used as effective monomers, and in particular, methacrylic acid improves the heat decomposition resistance of the copolymer obtained. desirable.

Examples of ethylenically unsaturated epoxy monopolymers include glycidyl methacrylate, methylglycidyl methacrylate, allyl glycidyl ether, etc., but glycidyl methacrylate and methylglycidyl methacrylate are effective in improving the dense layer properties of the copolymer. be.

Examples of ethylenically unsaturated carboxylic acid amide, N-alkylcarboxylic acid amide, N-methylolcarboxylic acid amide, and their alkyl ether monomers include acrylamide, methacrylamide, N-methylacrylamide, N
- diethyl acrylamide, maleic acid, fumaric acid, itaconic acid or other ethylenically unsaturated dicarboxylic acid 7/amide, diamide or ester amide, N-methylolacrylamide, N-methylolmethacrylamide, N-% as long as it is hydrophilic; Thiro/l/Ether examples of compounds are methyl ether, ethyl ether, 3-oxabutyl ether, 3,6-dioxahebutyl ether,
J, A, 9-) rioxadecyl ether and the like are mentioned as monomers that improve layer density.

Further, ethylene oxide addition products of N-methylolacrylamide, N-methylolmethacrylamide or &'LN-methylolmaleimide, N-vinylamide such as N-vinylacetamide, and N-vinylpyrrolidone may also be mentioned as hydrophilic monomers.

As the ethylenically unsaturated polycarboxylic acid, 1' obtained by a combination of hydroxyethyl acrylate, hydroxypropyl methacrylate, hydroxyethyl acrylate or hydroxyethyl methacrylate and succinic anhydride, phthalic anhydride, maleic anhydride or trimeliz anhydride 11' Monomers that are % ester compounds are mentioned.
Ru.

Well-known methods are adopted for polymerization, but as the undercarriage catalyst, it is recommended to use a normal radical undercarriage catalyst.
Here, specific examples include di-tert-butyl peroxide, dicumyl peroxide, methyl ethyl ketone peroxide, tert-butyl benzoate, tert-butyl benzoate, methyl isobutyl ketone peroxide, lauroyl peroxide, cyclohexyl peroxide 1.2.5- Dimethyl rouille, left-gee tθrt
Organic peroxides such as -butylperoxyhexane, tert-butylberocta/ate, tert-butylberisobutyrate, tert-butylberroisobutyrate, methylco, 2'-azobisisobutyrate, etc. rate, /, /'-azobiscyclohexanecarbonitrile, -monophenylazo, 2. lI-dimethyl-
Examples include azo compounds such as Hiro-methoxyvaleronitrile, -carpomoyl-azobisisobutyronitrile, 2,2'-azobisuyl, cage methylvaleronitrile, and 2,2'-azobisisobutyronitrile.

! ! l! As the chain transfer agent, alkyl mercaptan, which is usually used as a polymerization degree regulator, is used.

As the polymerization method, any of emulsion, suspension, bulk or solution I polymerization can be used, but the bulk polymerization method is preferred in order to obtain a highly pure polymer.

The jacket components of the present invention include thermoplastic outer car composites, such as polyethylene, polypropylene, borosilicate hibinyl, polyurethane, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, polyester elastomer, polyamide, borosilicate Vinylidene, polyvinyl fluoride, vinylidene fluoride, etc. are preferably used.

Blending carbon black into the thermoplastic shell of the jacket component (on the edge of the internal light transmitting body) is generally done to prevent damage or to prevent internal light leakage.

The blend M of the carbon blank is an important factor because it controls the contact strength between the jacket and the jacket, that is, the strength. The blending company of the carbon blank differs depending on the type of thermoplastic four-car combination used, but in general, it is preferably in the range of 0/~lO for the subcombination ioo
3-5 S is desirable. If the blending weight is below the O/L injection part, the material will leak, and if it is over 70°, the contact between the sheath and the jacket tends to be too strong.Next, referring to Drawing 24, the technical points of the present invention Explain.

In conventional Ritsu optical transmission cables, the interface between the core component (1) and the sheath component (,2) or (1 nitric acid component (,2) and the jacket component (3) was loose, so the cable was bent repeatedly. In this case, microcrazes occur in the sheath component (2) and the optical transmission performance is greatly reduced.

In the σ cable G of the present invention, since the sheath component (a) is copolymerized with a monomer that imparts hydrophilicity to G, that is, it has adhesion properties, the core component (1) and the sheath component (2) are copolymerized. denseness,
In addition, the denseness of the G moss sheath component (2) and the jacket component (3) has been improved, and in addition, the jacket component (3) has a stress σ due to the reinforcement effect from the outside caused by the G moss sheath component (2) and the sheath component (2). Since the occurrence of microcrazes in component (, 2) c has been reduced to a large lJ, the optical transmission performance will not deteriorate even when the cable is repeatedly bent. At this time, the sheath component (2) and the jacket component ( The ￥sexuality of 3) is the core component (1
) and the sheath component (, 2) must be substantially the same or smaller than the adhesion (3); otherwise, the interface between the core component (1) and the sheath component (, 2) will peel off. Undesirable.

In addition, the dense layer properties of the φtacic acid component 2) and the jacket component (3) must be 30 or higher in the cross-cut peeling strength test.
The effect of the present invention is not exhibited.

In the conventional 5'e File-Blu, when the cable is bent, the contact between the sheath component (2) and the jacket component (3) is loose, so the optical transmission fiber protrudes from the jacket cable at the terminal part. However, with the cable of the present invention, such a phenomenon does not occur, and the cable has good workability.

The manufacturing method of the optical transmission cable of the present invention can be briefly explained as follows.

The fibers can be loaded using the well-known slide-spinning method or solvent coating method, and the jacket coating can also be carried out using the well-known cable fiber method.

The optical transmission cable of the present invention can also be combined with a tensioned optical transmission cable or a copper wire.

Further, the optical transmission cable of the present invention is flame retardant or
It is also possible to provide a secondary coating to the heat-resistant thermoplastic outer car assembly.

Example/Ω,,2.2-)Lifluoroethyl methacrylate) 9
After mixing and dissolving 3 parts of methyl methacrylate, part of methacrylic acid, 0.05 parts of polymerization initiator azobisisobutyronitrile, and 1 part of n-dodecylbutane O, 1.21 The mixture was placed in an autoclave for bulk polymerization, and the mixture was repeatedly degassed and replaced with nitrogen, and then sealed.

Heat molding at soC for 70 hours and roughly at 7θC for S hours.
A sheath polymer having a refractive index of /25 was obtained.

This polymer was crushed using a crusher, and then a film of Oμ was prepared using a hot press.

- The ten-man core component is made into a continuous lump (10 θ parts of methyl methacrylate, 10 parts of methyl methacrylate, - Polymerization temperature/3SC1 average residence time IAO
The temperature of the vent extruder was adjusted to 30C at the vent part, 2 OC 1 press IJ 3 TO 30C, and the vacuum degree at the vent part lI.
After the volatile matter was separated by amH refrigeration, a core-sheath compound spinning head at 230C was supplied through a gear pump section maintained at 3θC. Only the core component is discharged and pelletized into a sheet of 21J+ core component.
Rishi T: .

In addition, the jacket If is 10% carbon black, 1% wire coated polyethylene (Nippon Unicar N0C90, 2A)
) was used to mold a 2 am thick sheet.

f) A 4'71 JE film was heat laminated with a core component sheet or a jacket component sheet (1) and then tested for cross force and peeling strength using the method described above. Next, the sheath polymer was discharged with the j1 sheath composite spinning head (this supply L, 2 J O'C). The yarn was spun at a take-up speed of 3 m/min, and the yarn was spun continuously at 1 loC.

A light transmission fiber with a core diameter of 9gθμ and a sheath thickness of 10μ was fabricated by stretching the fibers at the same time.

This message is sent'f11. The fiber was guided through the center G of the crosshead type cable processing hm v) tie, and the jacket polymer was melted and ruptured. Cable conditions are Gui Salt Isu/Guo
C, the take-up speed was J Om/min.

The outer diameter of the obtained optical transmission cable was 2 mm.

This optical transmission cable was repeatedly tested for attributes using the method shown in FIG. The number of times Tashamoto's light was bent until the retention rate reached 90% of the initial value was read and used as a measure of bending resistance. This transmission cable was extremely durable and could be bent 10,000 times.

Example A core fiber with a diameter of 10θμ was prepared from commercially available quartz rond, and a light transmitting fiber was prepared using a solvent coating method using a sheath polymer (Example/α).

The thickness of the sheath polymer was 50μ. When this fiber was coated with a jacket in the same manner as in Example 1, the outer diameter of the cable was 3000 times.

Examples 3 to 41, Comparative Examples, and Examples 1 to 4 were operated with a slight change in condition 1, and their performance was measured.

The important cable operating conditions and the performance of the obtained cables are summarized in the following table, including Examples/--〇].

2 PMMA polymethyl methacrylate SiG quartz glass pc polycarbofluoride-1 3FM, x, 2. p) Refluoroethi! Remethacrylate SFM, 2. ．． ? ,,? ,,? -Pentafluoropropylene methacrylate t, tFWI 2,2. J, 3-tetrafluoropropyl methacrylate ttF2M; t,,i,3,3. da, g, 5.5
-Octafluoropentyl methacrylate MMA Methyl methacrylate <' F A 2 , " + J , 3-Tetrafluoropropyl acrylate α-MSt α-Methylstyrene M A A Methacrylic acid AA Acrylic acid GMA Glycidyl methacrylate N-0AAn
N-octylacrylamide PE Polyethylene CB Carbon blank pt-VAC Ethylene-vinyl acetate copolymer PEs
polyester

[Brief explanation of drawings]

FIG. 1 illustrates a cross section of a typical optical transmission cable. Figure 2 shows a typical optical transmission cable in a bent state.
This is a diagram illustrating a cross section along the length of the cable. FIG. 3 explains a method for measuring the bending resistance of a couple. In Figures 1 and 2, (1) is the core component, (,2
) indicates the sheath component, and (3) indicates the jacket component.

Claims (3)

[Claims] (1) In a CC transmission cable consisting of an optical transmission fiber with a core-sheath two-wheel structure and a jacket portion covering the self-transmission fiber, the sheath component is made of an organic polymer, and the core component and sheath component are Strength: Substantially the same as or greater than the peeling strength between the sheath component and the jacket component, and the peeling strength between the sheath component and the jacket component is cross-cut. A self-transmission cable with excellent bending resistance G, which is characterized by a peeling strength test of 30 or higher. (2) The sheath component organic polymer is an organic polymer formed by polymerizing 0 to 70 parts of fluorinated alkyl methacrylate acid with O/~3 parts of fluorinated alkyl methacrylate. The Y6 transmission cable according to claim 1, characterized in that: (3) The jacket component is O/carbon black.
The optical transmission cable according to claim 1, characterized in that it is an organic polymer blended with ~/θ.