JPH05313016A - Light transmission hose - Google Patents

Abstract

PURPOSE:To prevent the infiltration of gas into core liquid so as to maintain the transparency of a light transmission hose in a wide temperature range for a long period of time by covering the outer periphery of a hollow tube shaped clad material with material of high gas barrier property. CONSTITUTION:Liquid or flowable core material 2 higher in refractive index than clad material 1 is filled inside a hollow tube shaped clad material 1, and both end opening parts of the clad material 1 are closed by sealing plugs 3. The outer periphery of the clad material 1 is covered with material of high gas barrier property. Accordingly, even in the case of the internal pressure of the core liquid 2 being lowered by the use under low temperature so as to place the hollow part of the clad material 1 into the vacuum state, gas is not permeated from the tube wall of the clad material 1 so as to effectively prevent the generation of bubbles in the core liquid 2. The transparency of a liquid transmission hose is thereby maintained in a wide temperature range, and the increase of weight is prevented since the hollow part of the clad material 1 is not placed in the vacuum state.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical transmission hose in which a core material is in a liquid or fluid state, and more specifically, it prevents gas from entering the core material and is excellent in flexibility. The present invention relates to an optical transmission hose that does not lose its function over a long period of time.

[0002]

2. Description of the Related Art Conventionally known optical fibers include inorganic glass based optical fibers such as quartz glass and multi-component glass, and plastic based optical fibers such as polymethylmethacrylate and polystyrene, both of which have a solid core and clad material. It is an all-solid-state optical fiber made of material.

Although these optical fibers have excellent characteristics, they are limited in flexibility because they are made of glass or a hard plastic material, and when they have a large diameter for transmitting a large amount of light. , Diameter 10-1000μ
It is necessary to bundle a large number of optical fibers of about m.
However, no matter how densely the optical fibers are bundled, since the voids remain between the fibers, the effective light-receiving area when light is incident becomes narrow, resulting in poor efficiency and a very high cost. was there.

As a solution to these problems of the all-solid-state optical fiber, the inventors of the present invention disclosed in Japanese Patent Laid-Open No. 64-809.
10 and 64-80912 (U.S. Pat. No. 4009).
382, 3814497) proposed an optical transmission hose using an optical transmission medium that is liquid at room temperature. In these liquid optical fibers, a clad material composed of a flexible hollow tubular body is filled with a liquid core material having a refractive index higher than that of the clad material, and openings at both ends of the clad material are closed by window materials. Therefore, it was easy to increase the aperture, had a wide effective light receiving area, high efficiency, and was excellent in economic efficiency.

[0005]

However, although the liquid-type optical fiber has excellent characteristics as described above, when used for a long period of time, gas penetrates into the core liquid, resulting in a decrease in transparency. There was a point. Since the core material is a liquid, the expansion coefficient is generally larger than that of a hollow tubular clad material made of a resin material, and therefore at a low temperature, the volume of the core liquid becomes smaller than the inner volume of the clad material, Since the hollow portion of the clad material is in a negative pressure state, gas permeates through the tube wall of the clad material, and this gas causes bubbles in the core liquid.

[0006] As a liquid type optical fiber which solves such a problem of gas invasion, for example, British Patent 1450608.
There are optical fibers proposed in the issue. This optical fiber consists of a core liquid reservoir connected to a hollow tubular clad material, and the core liquid is supplied from the reservoir even when the volume of the core liquid becomes small at low temperatures, so the hollow part of the clad material is under negative pressure. It is possible to prevent gas from entering the core liquid without causing a state.

However, in this optical fiber, it is necessary to make a hole for liquid inflow in the clad material when connecting the reservoir and the hollow tubular clad material,
Light scattering occurs at the holes, and the transparency is reduced. Further, since the reservoir is attached, there is a problem that it is heavy and expensive.

The present invention has been made in view of the above circumstances,
An object of the present invention is to provide a lightweight and inexpensive optical transmission hose capable of preventing gas from entering the core liquid and maintaining transparency of the optical transmission hose over a wide temperature range for a long period of time.

Means and Actions for Solving the Problems As a result of intensive investigations by the present inventors to achieve the above object,
In an optical transmission hose in which a hollow or tubular clad material is filled with a liquid or fluid core material having a higher refractive index than the clad material, and both end openings of the clad material are closed with sealing plugs, When the outer periphery of the clad material is coated with a material having a high gas barrier property, it is used at a low temperature, and even if the inner pressure of the core liquid is reduced and the hollow part of the clad is in a negative pressure state, the gas from the clad material tube wall Since it is possible to effectively prevent the generation of air bubbles in the core liquid after permeation, the transparency of the optical transmission hose is maintained in a wide temperature range, and the outer circumference of the clad material is covered with a material having a high gas barrier property. Since the hollow portion of the clad material is prevented from being in a negative pressure state by doing so, it was found that the weight does not increase and the manufacturing cost is low, and the present invention is made. Was Tsu.

The present invention will be described in more detail below. The optical transmission hose of the present invention comprises a hollow tubular clad material,
In an optical transmission hose in which a liquid or fluid core material having a higher refractive index than the clad material is filled and both end openings of the clad material are closed with sealing plugs, the outer periphery of the clad material is provided with a gas barrier property. It is coated with a high material.

FIG. 1 shows an example of the optical transmission hose of the present invention. In FIG. 1, 1 is a hollow tubular clad material, 2 is a liquid or fluid core material filled in the clad material 1, 3 is a sealing plug for holding the internal pressure of the hollow part of the core material and the clad material, 4 is a gas barrier coating material that covers the outer periphery of the clad material 1. Reference numeral 5 is an end fastener for preventing the sealing plug 3 from coming off and the core material 2 from leaking.

Here, as a material for forming the hollow tubular clad material 1, it is preferable to use a flexible material such as plastic or elastomer, which can be formed into a tube and has a low refractive index. .. Specific examples thereof include polyethylene, polypropylene, polyamide, polystyrene, ABS, polymethylmethacrylate, polycarbonate, polyvinyl chloride, polyvinylidene chloride, polyvinyl acetate, polyethylene-vinyl acetate copolymer, polyvinyl alcohol, polyethylene-polyvinyl alcohol copolymer. Polymer, fluororesin, silicone resin, natural rubber, polyisoprene rubber, polybutadiene rubber, styrene-butadiene copolymer, butyl rubber, halogenated butyl rubber, chloroprene rubber, acrylic rubber, EPDM, acrylonitrile-butadiene copolymer, fluororubber, Silicon rubber etc. are mentioned.

Of these, silicone-based polymers and fluorine-based polymers having a low refractive index are particularly preferable. Specifically, silicone-based polymers such as polydimethylsiloxane polymer, polymethylphenylsiloxane polymer and fluorosilicone polymer, and polytetrafluoroethylene (P
TFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), tetrafluoroethylene-perfluoroalkoxyethylene copolymer (PFE), polychlorotrifluoroethylene (PCTFE), tetrafluoroethylene-ethylene Copolymer (ETFE), polyvinylidene fluoride, polyvinyl fluoride, vinylidene fluoride-trifluorochloroethylene copolymer, vinylidene fluoride-hexafluoropropylene copolymer, vinylidene fluoride-propylene hexafluoride- Examples thereof include tetrafluoroethylene terpolymer, tetrafluoroethylene propylene rubber, and fluorinated thermoplastic elastomer.

These materials may be used alone or as a mixture of two or more kinds, and may be used as a single tube or a multiple tube. Furthermore, only the inner surface in contact with the core liquid can be subjected to a treatment such as a smoothing treatment by a method such as coating or double extrusion.

As the core material 2 filled in the hollow portion of the hollow tubular clad material 1, a liquid or fluid transparent material having a higher refractive index than the clad material is used. Specific examples thereof include aqueous solutions of inorganic salts, polyhydric alcohols such as ethylene glycol and glycerin, silicone oils such as polydimethylsiloxane and polyphenylmethylsiloxane, hydrocarbons such as polyether, polyester and liquid paraffin, and trifluorochlorochloride. Examples thereof include halogenated hydrocarbons such as ethylene oil, phosphoric acid esters such as tris (chloroethyl) phosphate and trioctylphosphate, and polymer solutions obtained by diluting a polymer with a suitable solvent.

The material forming the sealing plug 3 is inorganic glass,
It can be selected from organic glass, metals, inorganic materials, plastics and the like according to the purpose. For example, as shown in FIG. 2, the sealing plugs 31 and 32 are transparent in order to allow light to enter the light transmission hose body and to act as a window material for light that transmits the light. However, for example, when the light is emitted from the side surface of the hose as shown in FIG. 3, the end sealing plug 32 does not necessarily have to be transparent.

Specifically, when transparency is required as the material for the sealing plug, quartz glass, multi-component glass, sapphire, inorganic glass such as quartz, polyethylene, polypropylene, ABS resin, acrylonitrile / styrene copolymerization. Resin, styrene / butadiene copolymer, acrylonitrile / styrene copolymer resin, styrene / butadiene copolymer, acrylonitrile / EPDM / styrene terpolymer, styrene / methyl methacrylate copolymer, methacrylic resin, epoxy resin, polymethyl Pentene, allyl diglycol carbonate resin, spirane resin, amorphous polyolefin, polycarbonate, polyamide, polyarylate, polysulfone, polyallylsulfone, polyethersulfone, polyetherimide, polyimide, polyethylene It is preferable to use organic glass or plastic transparent material such as terephthalate, diallyl phthalate, fluororesin, polyester carbonate, and silicon resin. Among them, quartz glass, Pyrex glass, inorganic glass such as multi-component glass is not only transparent, Since it has excellent heat resistance and is chemically stable, the core material 2 contacting at the end surface 3a and the end surface 3b
It does not chemically react with the gas or moisture that comes into contact with it, and can provide excellent performance in the long term.

When transparency is not required, stainless steel such as Cr—Fe and Cr—Ni—Fe and metal and ceramic materials such as Al, Fe, Ti, Cu and Shinchu can be used in addition to the above materials. .. In this case, it is preferable to polish at least the surface of the sealing material that is in contact with the core liquid or to provide a reflective film in order to reflect the light with the sealing material and increase the light emission from the side surface.

As the material of the gas barrier coating material 4, it is preferable to use a material which has a high gas barrier property and does not impair the flexibility of the optical transmission hose, and is selected from plastics, elastomers, metals, inorganic materials and the like. can do.

Specifically, polyvinyl alcohol, ethylene-vinyl alcohol copolymer, polyvinylidene chloride, polyvinyl fluoride, polyester, polychlorotrifluoroethylene, phenol resin, polyamide, epoxy resin, polyacrylonitrile, polyvinyl chloride, Cellulose, acetal resin, polycarbonate, acrylic resin, polystyrene, fluororesin, butyl rubber, halogenated butyl rubber, polyethylene, polypropylene, polyurethane, polyvinyl acetate, polyethylene-vinyl acetate copolymer, hydrochloric acid rubber, natural rubber, polyisoprene rubber, polybutadiene Rubber, styrene-butadiene copolymer, butyl rubber, halogenated butyl rubber, chloroprene rubber, acrylic rubber, EPDM, acrylonitrile-butadiene copolymer, phenyl rubber Examples include polymeric materials such as base rubber, metals such as stainless steel, aluminum, copper, iron, zinc, tin, brass, bronze, silver and gold. These materials may be used alone or as a composite with other materials. Can be used.

Among them, the gas barrier property is high, the transparency is
Particularly, vinyl chloride, polyvinyl alcohol, ethylene-vinyl alcohol copolymer, and polyvinylidene chloride are preferably used because they have excellent environment resistance and processability and are easily available. In this case, the thickness of the covering material 4 is preferably 0.01 to 10 mm, particularly 0.5 to 2 mm.

In order to cover the outer periphery of the clad material 1 with these materials, a method such as coating, extrusion molding, winding a tape-shaped material, heat shrinkage treatment, etc. can be adopted. Alternatively, a method of inserting an optical transmission hose whose outer periphery of the clad material is not covered with a gas barrier material into a flexible tubular material formed of the polymer material or the metal material may be used. In this case, silicone oil, fluorine oil, ethylene glycol, water, liquid paraffin should be used to prevent gas such as air existing in the gap between the upper air light transmission hose and the flexible pipe from entering the light transmission hose. Liquid or silicone rubber, etc.
It is preferable to seal with a polymer material such as urethane rubber. Further, the metal material may be coated on the outer periphery of the clad material or the inner surface or outer periphery of the coating material by a method such as plating, vapor deposition, and sputtering.

The terminal fastening portion 5 is provided to prevent the sealing plug from coming off and the core liquid from leaking, and also to prevent gas from entering from the joint end of the clad material 1 and the gas barrier coating material 4. , Mechanical sealing such as tightening with a hose band, winding with a wire wire, tightening through a sleeve, O-ring, packing, etc., heat shrinkage treatment, adhesive treatment, sealing with a curable material, etc. Can be performed alone or in combination. Among them, sealing by mechanical caulking using a die is preferably used, and as the material of the die, iron, nickel, Fe—Cr—Ni alloy, aluminum, brass, titanium, or the like can be used.

[0024]

EXAMPLES The present invention will be specifically described below by showing Examples and Comparative Examples, but the present invention is not limited to the following Examples.

[Example 1] Inner diameter 12 mm, outer diameter 13 m
m, 3 m long, tetrafluoroethylene / propylene hexafluoride copolymer hollow tubular clad material coated with polyvinyl chloride resin to a thickness of 1 mm. Trioctyl phosphate was added to the hollow part of the double tube. After filling, both ends have a diameter of 13m
A quartz rod having a length of m and a length of 50 mm was inserted, and the end portion was bound with a wire.

When this optical transmission hose was left standing in a refrigerator at -5 ° C., no air entered even after about 6 months, and high light transmittance was maintained.

[Example 2] An optical transmission hose was prepared in the same manner as in Example 1 except that a polyethylene-vinyl acetate copolymer (vinyl acetate amount: 25%) was used as the coating material instead of the polyvinyl chloride resin. ..

The optical transmission hose was left to stand in a refrigerator at -5 ° C., but no air entered even after about 6 months, and high light transmittance was maintained.

[Comparative Example] An optical transmission hose was produced in the same manner as in Example 1 except that the cladding material was not coated.

When this optical transmission hose was allowed to stand in a refrigerator at -5 ° C, about 1 ml of air was generated in the core portion after 2 days, and the light transmittance was reduced to 40% from 70% before entering the air. did.

[0031]

EFFECTS OF THE INVENTION According to the present invention, the flexibility and handleability are excellent, and the transparency of the optical transmission hose is maintained for a long period of time in a wide temperature range by preventing gas from entering the core liquid. It is possible to obtain a lightweight and inexpensive optical transmission hose.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of an optical transmission hose of the present invention.

FIG. 2 is a sectional view showing another embodiment of the optical transmission hose of the present invention.

FIG. 3 is a sectional view showing another embodiment of the optical transmission hose of the present invention.

[Explanation of symbols]

 1 clad material 2 core material 4 gas barrier coating material

Claims (1)

[Claims] 1. A light obtained by filling a hollow tubular clad material with a liquid or fluid core material having a refractive index higher than that of the clad material, and closing both end openings of the clad material with sealing plugs. In the transmission hose, an outer circumference of the clad material is coated with a material having a high gas barrier property, which is an optical transmission hose.