KR102018124B1 - Optical network duct formed with sheet shaped outer covering material - Google Patents

Abstract

In the optical communication network duct formed of the sheet-like outer cladding according to the present invention, after the plurality of primary tubes are fixed to the sheet-shaped outer cladding in parallel, a plurality of primary tubes may be used. It is characterized by being formed so as to be positioned inside. The optical communication network duct formed of the sheet-like outer cladding according to the present invention can be loaded and transported with the outer cladding unfolded, thereby significantly reducing transportation costs, and simplifying manufacturing facilities and manufacturing processes by eliminating complicated coextrusion processes. It can reduce the production cost and the defective rate, solve the bending problem caused by the bobbin wound during transportation, and it is easy to remove and re-install the external coating material at the construction site, so that the addition of the primary tube of the existing duct Additional laying or separating operations are possible, making maintenance easy and reducing costs.

Description

OPTICAL NETWORK DUCT FORMED WITH SHEET SHAPED OUTER COVERING MATERIAL}

The present invention relates to an optical network duct.

In installing an optical communication network, a technique of laying an air-blown cable (optical cable) 2 in the duct 50 using air pressure is widely used as shown in FIG. 1.

The basic form is composed of a plurality of primary tubes 20, which are long thin tubes made of a polymer, and an outer covering 40 which surrounds them. This is a general form of the duct 50 applied to all existing optical communication network has a structure as shown in Figs. Therefore, the production, production, installation and construction, installation, transportation, storage, and post management are all very similar.

This structure has been applied and used quite easily, depending on the size (traffic volume) and location (ground, ground, seabed, etc.), or according to the user or internationally required properties, suitable for the purpose of the optical network to be constructed. Depending on (flame retardancy, chemical resistance, heat resistance, tensile strength, acupressure or hardness according to impact), a complicated application as shown in FIG. 4 is also possible.

In FIG. 4, in the case of the direct duct, the outer covering material 40 surrounding the primary tube 20 is composed of three layers of the outer layer 42, the inner layer 44, and the aluminum layer 46. 22 represents a rip cord. In the case of the duct for the pipeline, the outer covering member is made of two layers of the outer layer 42 and the aluminum layer 46, and in the case of the flame retardant duct, the outer covering member 40 is made of a single layer.

Air blown cable (2), which is an optical network cable installed using air pressure in general, is individually assembled or integrated into a single tube by extruded or coextruded tubular coating through an extruder at the time of manufacture of the pipe. It is then shaped into a large diameter pipe, or directly buried underground, or installed on the ground.

However, the outer covering 40 for laying the air blown cable 2 using air pressure did not escape from the basic form of a tube, and thus accompanied the following problems.

(1) The structure becomes complicated according to the function to have a multi-layered tube structure, and the manufacturing process also produces an inner primary tube 20, and then again produces an outer coating material 40 to be seated and inserted therein. Is added.

(2) As the coextrusion according to the multi-layer structure increases, the apparatus equipment at the time of manufacture increases, the production process becomes complicated, and the defective rate increases accordingly.

(3) The duct 50 used for the general optical network cable 2 includes the outer covering 40 and the primary tubes 20 such as 1, 2, 4, 7, 12, 14, 19, 24, and the like. It is composed of a combination. Since the number of primary tubes 20 is already determined before production according to the market demand (capacity and scale) by the user, it is impossible to apply the proper loading location according to the construction because it is impossible to expand, reduce or adjust the number of items and grades. Becomes

(4) It is not possible to insert or remove the primary tube 20 at the construction site.

(5) As the capacity of the optical communication network increases, the number or aperture of the primary tubes 20 increases. Then, the diameter of the duct 50 is also increased, and accordingly, the core of the bobbin 54, which is a circular structure for winding the duct 50, needs to be large (FIG. 5). If the core is small, because the diameter of the duct 50 is large, the bending radius of the duct is small, and the duct is unreasonable. The larger the core, the greater the cost of transportation and loading.

(6) The duct 50 wound on the bobbin 54 becomes hard in accordance with the low temperature and high temperature environment changes, and the bending remains without being completely unfolded during construction. Then, the flow of the fluid is disturbed when the air blown cable 2 is transmitted by the high pressure air pressure.

(7) After construction, the duct 50 cannot be disassembled and expanded or rolled, so the whole duct should be replaced when a problem occurs.

The present invention is to solve the above problems, it is possible to significantly reduce the transportation cost by loading and transport operation with the outer coating material unfolded, and by eliminating the complex co-extrusion process and the production cost and production process by simplifying the manufacturing process and It can reduce the defective rate, solve the bending problem caused by the bobbin wound during transportation, and it is easy to remove and re-install the external coating material at the construction site, so that the addition of the primary tube of the existing buried duct and additional laying work Or it is an object of the present invention to provide an optical network duct that can be separated and easy to maintain and reduce the cost.

In order to achieve the above object, an optical communication network duct formed of a sheet-type outer cladding material according to the present invention comprises a sheet-shaped outer cladding material having a plurality of primary tubes fixed thereto after a plurality of primary tubes are fixed in parallel to the sheet-shaped outer cladding material. A plurality of primary tubes are characterized in that the roll is formed to be located inside.

The optical communication network duct formed of the sheet-like outer cladding according to the present invention can be loaded and transported with the outer cladding unfolded, thereby significantly reducing transportation costs, and simplifying manufacturing facilities and manufacturing processes by eliminating complicated coextrusion processes. It can reduce the production cost and the defective rate, solve the bending problem caused by the bobbin wound during transportation, and it is easy to remove and re-install the external coating material at the construction site, so that the addition of the primary tube of the existing duct Additional laying or separating operations are possible, making maintenance easy and reducing costs.

1 illustrates an apparatus for installing an air blown cable inside an optical network duct using air pressure.
2 shows various optical communication network tufts.
3 shows two examples in which cables are installed in an optical network duct.
Figure 4 shows various examples according to the use of the optical network duct.
Figure 5 shows a state in which the optical network duct is wound on the bobbin.
Figure 6 simply shows a manufacturing method of the optical network duct according to the present invention.
Figure 7 shows the outer covering material (single layer) of the optical network duct according to the present invention.
8 shows an outer covering material (two layers) of the optical network duct according to the present invention.
9 shows an outer covering material (three layers) of the optical network duct according to the present invention.
10 is a graph measuring the interlayer bonding force of the outer coating material (two or more layers) of the optical network duct according to the present invention.
11 shows a method for testing the interlayer adhesion holding force of the outer covering material (two or more layers) of the optical network duct according to the present invention.
12 is a diagram illustrating a mechanism for forming a strong bond between an inner layer and a metal layer of an outer covering of an optical network duct according to the present invention.
Figure 13 shows the outer covering material (5 layers) of the optical network duct according to the present invention.
FIG. 14 schematically shows before and after adding an additive for strengthening heat resistance and shrinkage resistance to a base polymer of an outer coating material of an optical communication network duct according to the present invention.
Figure 15 shows that the textile fiber is impregnated into the outer coating material of the optical network duct according to the present invention.

In the optical communication network duct 30 formed of the sheet-like outer cladding 10 according to the present invention, the plurality of primary tubes 20 are arranged in parallel and fixed to the sheet-like outer cladding 10, and then the plurality of primary tubes 20 are fixed. ) Is formed by rolling a sheet-like outer cladding 10 to which a plurality of primary tubes 20 are located.

Specifically, as shown in FIG. 6, a plurality of primary tubes 20 are disposed and fixed in a sheet-like outer covering material 10 (the outer covering material and the primary tube are unfolded) and transported to the construction site. Then, at the construction site, the outer covering 10 is made so that the primary tube 20 is located inside, and then the both ends of the outer covering 10 are bonded to form the duct 30.

Alternatively, the primary tube 20 is transported to the construction site in each state in which the primary tube 20 is not fixed to the sheet-like outer sheath 10, and then the primary tube 20 is disposed on the sheet-like outer sheath 10 at the construction site. The outer cover 10 may be fixed so that the primary tube 20 is positioned inward, and then both ends of the outer cover 10 may be bonded to form the duct 30.

The optical network duct 30 according to the present invention is composed of an inner primary tube 20 and an outer outer covering material 10, where the outer covering material 10 may be composed of a single layer or two or more layers.

1. Outer cladding is single layer

In the tubular extrusion applied to the conventional optical network duct 50, it is difficult to realize the biaxial stretching effect, and the modification of the material for changing the tensile strength or the mechanical properties was virtually impossible. As a result, single layer outer cladding was generally a high density polyethylene material with high tensile strength (high molecular weight, low MI, low elongation).

However, in the case of the sheet-like outer cladding 10 of the present invention, the biaxial stretching effect can be applied at the time of sheet production, and thus the material can be freely modified according to the required physical properties of the market.

Therefore, depending on the required tensile strength, chemical resistance and impact resistance, polyolefins (high density polyethylene, low density polyethylene, linear low density polyethylene, polypropylene, etc.), polyethylene vinyl acetate, polyethylene vinyl alcohol, polyamides (nylon 6, nylon 66, nylon 12) Etc.) What is necessary is just to use at least one of polyethylene terephthalate as a base polymer.

0 ~ 30 additive of at least one of CaCO ₃ , BaSO ₄ , talc, SiO ₂ , molybdenum clay, and silicone oil used as inorganic filler or functional modifier according to the market property demand such as wear resistance, surface hardness, gloss, transparency % Can be added. In addition, in order not to reduce the tensile strength, a particle size in the range of 500 to 100,000 mesh (50 μm to sub μm 1) is applied.

In the case where electrical conductivity or antistatic property is required, at least one of metal or metal salt carbon, MgO, graphene, carbon nanotube, H-BN, ZnO, Al ₂ O ₃ , AIN, and SiC may be selected.

As a slip agent, a lubricant, a mold release agent, an antiwear agent, and an antifriction agent, at least one of silicone oil or wax, stearate-based or metal salt stearate-based (Zn-stearate, etc.), molybdenum, and the like may be added at a weight ratio of 1 to 15 phrs. have.

2. Outer covering material is 2 layers

In order to meet the required physical properties (market standard properties) against the external environment, the optical communication network duct that requires pneumatic laying and construction requires the outer surface of the outer cladding 10 to have chemical resistance (chemical resistance), heat resistance, air tightness, rigidity, and hardness. , Coloration (coloring, gloss, transparency), flame retardancy, flame resistance, etc. is required, but the inner surface of the outer coating material 10 is inserted into the primary tube 20 designed to withstand high pressure air pressure without a connection 1 ~ 2km or more As such, it requires abrasion resistance, friction resistance, or connection bonding with the primary tube 20 inserted into several strands depending on the internal cable format. In consideration of this, the material of the outer covering 10 should be selected.

In addition, when the two-layer sheet is applied for the optical network duct, the manufacturing method and material are different according to the following classification.

In FIG. 8, when the material of the outer layer 12 and the inner layer 14 is the same polymer, it is easily produced by a process such as co-extrusion of a general T-die type or roller pressing by heat fusion after individual production. It is possible.

On the other hand, when the materials of the two layers 12 and 14 are not homogeneous polymers, the two layers 12 and 14 should be manufactured by T-die co-extrusion or three-layer roller casting using an adhesive resin for reliably bonding between the two layers.

In such a structure, if the adhesive layer for adhesion is regarded as another layer, it may be coextruded at once in a 3 T-die line, and each layer is produced separately and bonded by a casting method through a heating roller. Production is possible.

The material of the outer layer 12 may be manufactured by applying the material of the single layer described above.

The choice for the adhesive resin is a suitable material for fusion if the base polymer of the outer layer 12 is an olefin series and the base polymer of the inner layer 14 is polyethylene vinyl acetate, a polyamide (nylon 6, 66, 12) series. It is preferable to use a polyethylene vinyl alcohol series.

3. Outer covering material is three layers

The optical network duct of the present invention may be composed of three layers in the order of the outer layer 12, the inner layer 14, the metal layer 16 as shown in FIG. The base polymer used for the outer layer 12 and the inner layer 14 is at least one selected from the group consisting of polyolefins, polyamides and polyethylene terephthalates, and the material of the metal layer 16 is selected from the group consisting of aluminum, iron and magnesium. It is preferable that it is at least one.

In this case, each layer (12, 14, 16) can be manufactured in a three-layer structure that can be separated or easily peeled off rather than completely bonded. This is to facilitate the expansion connection of the cable at the time of extension connection of the duct 30, and to facilitate maintenance.

In the existing duct form, but using a complex process such as inserting after molding in an extruder, in the sheet form of the present invention, as shown in Figure 6 the outer coating material 10 is loaded only when it is coupled with the primary tube 20, Easy to carry and install

Furthermore, in order to facilitate the additional insertion or maintenance of the primary tube 20 after laying and construction, it should be manufactured using a method such as adhesion or temporary adhesion. The method devised in the present invention in this case is as follows.

About the bonding method between each layer which forms the outer coating material 10, the adhesive resin of this invention was devised in consideration of the following. It is divided into adhesive, adhesive, hot melt type, adhesive / adhesive tape.

(1) In the case of using an adhesive, a non-persistent adhesive made of polymer (bonding has no persistence and decreases adhesive strength after curing) for ease of connection and maintenance of the cable, and at the interface of each layer Adhesives that follow physical adhesion mechanisms, such as Pandervals bonds, are used rather than chemical bonds that damage the surfaces that make up the surface.

At this time, the bonding force has sufficient tensile pressure and bonding force at the time of construction, and when maintaining and connecting the connection pipe, it should be possible to separate each layer constituting the outer covering material 30 in the field without additional equipment. To this end, the coupling force may be measured as shown in FIG. 10, and in order to satisfy the international standard of the optical network duct 30, it should be maintained in the range of 3 to 30 kgf / cm ² at -20 to 50 ° C.

(2) When using the adhesive can be applied in the range of 3 ~ 20kgf / cm ² at -20 ~ 50 ℃.

Due to the characteristics of the duct 30 used in the optical communication network, the component structure of the pressure-sensitive adhesive to be applied should be composed of an elastic body and a tackifying resin. The ratio and composition of these should be changed and applied according to the specification of the maintenance of the duct 30 and the connection of the joint.

In addition, in the nature of the material configuration, it is necessary to maintain elasticity in order to maintain the persistence of the external exposure material 10 of the duct 30, in accordance with the temperature change of the external environment in which the optical communication network is installed at the critical upper limit temperature and the lower limit temperature. Should be synthesized and applied.

In addition to the bonding force to prevent peeling, the pressure-sensitive adhesive is applied by measuring the change in viscosity to maintain the persistence, and the change in adhesive holding power as shown in FIG.

(3) Even in the case of hot-melt type and adhesive / adhesive tape, the bonding strength range of the pressure-sensitive adhesive is consistent.

(4) To satisfy the above (1) to (3) and to apply the market purpose (ground, underground, indoor, seabed, coast, etc.) and climatic environment (tropical, tropical, cold, toxic gas environment, humidity environment) ), And depending on the material of each layer, the adhesive resin may be acrylic, acrylic (anaerobic), olefin, olefin (hot melt), urethane, urethane (emulsion), ether cellulose, ethylene-vinyl acetate resin (emulsion), Ethylene-vinyl acetate resin (hot melt), epoxy type, epoxy type (emulsion), vinyl chloride resin (solvent type), vinyl acetate resin (emulsion), chloroprene rubber type, cyanoacrylate type, silicone type, modified silicone type, aqueous polymer Isocyanate type, styrene butadiene rubber, styrene butadiene rubber (latex), nitrile rubber, nitrocellulose type, polyamide type (hot melt), polyimide type, polyvinyl acetate resin (solvent type), polystyrene resin (solvent type), Polyvinyl alcohol To, polyvinyl pyrrolidone, polyvinyl butyral, poly benzimidazole type, polymethacrylate-based (solvent-based), melamine resin, at least one selected from urea resin and resorcinol when the group consisting of play to step is preferred.

In addition, the control of the required physical properties (adhesive strength, persistence, adhesion hardening, environment in which the duct is laid, antistatic property) for the adhesive force can be controlled by the mineral fillers CaCO ₃ , BaSO ₄ , talc, SiC or SiO ₂ , Al ₂ O ₃ , Al (0H) ₃ , Mg (OH) ₂ , molybdenum or molybdenum oxide, carbon, carbon nanotubes, MgO and at least one selected from 0 to 12% by weight, or by adjusting the surfactant (anion, cation) Or it adjusts by adding oil, such as an antifoamer and a neutralizing agent, in the weight ratio of 0-1%.

This may be equally applied to adhesives, pressure-sensitive adhesives, pressure-sensitive adhesive tapes, hot melt systems depending on the formulation configuration for each layer.

However, there exists a construction site which is insufficient only by the bonding force of the adhesive, the adhesive, the hot melt, and the adhesive / adhesive tape mentioned in the above (4).

In places where the network is installed, the pressure in the ground is severe, the pressure is increased in long cables such as the seabed, the temperature is severely changed, such as the desert, or when the long distance is required to have a very high tensile strength. In order to maintain the physical properties of each outer layer of the outer covering 10 without peeling, a strong bond is required.

In addition, in the composite outer cladding with the addition of a thin layer of metal, which can be applied / implemented to a special purpose environment by using the sheet-shaped outer cladding 10 of the present invention, the bonding force between heterogeneous materials such as metal and polymer It is significantly lower than the bonding force.

Existing hardened physical-chemical adhesives, or Pandervals bonding, which is a bonding mechanism of physical adhesives, cannot be easily handled. To this end, in the present invention, in order to maintain a strong bond to high pressure, large temperature change, chemically modify the surface, or end groups of polymers (mainly present in the outer coating material -CH ₃ , = O, -COOH, -OH groups Etc.) By using chemical mechanisms such as substitution sharing or electron substitution and crosslinking of the main chain (the outer covering material is mainly made of carbon chain -C-), which forms a polymer, direct chemical bonds are bonded to each layer. The method was chosen.

In the co-extruded tubular duct, which is a general method of producing the existing optical network duct, it was difficult to apply due to the problems of equipment, equipment, and process. This is because it is impossible to separately add additives of different natures in one machine to form each layer. In the process of forming the sheet-like outer cladding 30 of the present invention, after producing each layer, heat fusion, thermocompression, biaxial stretching, application of auxiliary additives by a casting film that can be repeatedly performed (for example, a surface Activation of the surface or interface, or by the addition of peroxides to activate the polar end groups at the surface or interface, or by the effect of adsorption, coating, or embossing of the common covalent bonds contained in the heterogeneous materials on the other side, the surface area is increased or the surface etching is realized. This can be expressed as “planting chemical anchors”).

Adhesive resin for realizing the purpose of high pressure, strong coupling of the optical network duct 30 of the present invention was developed as follows.

In this case, there are largely a heat welding method and a pressing method, but the pressing method adds an additive to the adhesive bonding method (similar to the method of (2) above), or similar to the sheet manufacturing process of a general sheet maker, Only the thermal welding method by surface modification is mentioned.

12 schematically shows the mechanism by which the inner layer of the present invention makes a strong bond with the metal layer surface.

The material of the inner layer 14 is polyolefin (polyethylene, polyethylenevinylacetate, polypropylene, etc.) or polyamide (nylon, etc.), and the heterogeneous layer 16 to be bonded is a metal series (aluminum, iron, magnesium, or other oxidized material). In the case of a sheet-like strip of a metal type, the adhesive resin contains 70% or more of the base resin regardless of whether the additive (objective modifier, flame retardant, high tensile, etc.) contained in the inner layer contains an inorganic substance or an organic substance. Then, peroxide (H ₂ O ₂ ) is added to 0.06% to 3.5% of the base resin, and maleic anhydride is added to 0.18 to 10.5% of the base resin to prepare.

The addition ratio of the peroxide and maleic anhydride follows the content ratio of the base resin of the inner layer 14, but is maintained by maintaining 1: 3. Maleic anhydride resin can be used interchangeably like ethylene-maleic anhydride resin. Stearate acid may be used depending on the additive contained in the base resin.

If the content of the base resin is low and physical properties such as tensile strength of the adhesive resin occur, in order to reinforce it, butadiene rubber, TPX-based rubber modifier, and styrene-based resin are mixed with the base resin by 20 to 40%. And graft copolymerization in the reactor.

The reaction temperature at the time of copolymerization of adhesive resin is 130-210 degreeC, and it should be processed at low temperature as much as possible, and the reaction temperature at the time of bonding is 20-50 degreeC higher than the reaction temperature at the time of copolymerization. This is to maintain the maximum reactivity of the end group in the production of the material, and to induce instantaneous chemical corrosion (oxidation) of the metal surface to be sufficiently bonded at the time of bonding.

If the temperature is high at the time of manufacture of the material, the bonding group is lost due to the self-crosslinking between the end groups, or if the temperature is too low at the time of bonding with the metal surface, the bonding strength is lowered, and if the temperature is too high, a large amount of gel may be obtained by self-crosslinking It may be formed to roughen the surface of the outer cladding sheet, which may also cause a decrease in the bonding force.

The surface of the metal layer to be bonded can be used by removing foreign substances (dust, dirt, wax, rust preventive oil, release agent, etc.), or by etching, embossing, scratching, or sanding to increase the surface area of the interface to increase bonding strength. have.

4. Outer covering material is 5 layers

The structure, which has not been realized due to the complexity or inefficiency of the productivity for production by the conventional tubular coextrusion method, has also been realized according to the present invention. As an example, the outer covering material 10 has five layers.

The area where the optical communication network is installed requires chemical resistance, blocking of oxygen, sulfurous acid gas, etc., high heat resistance against temperature is required, and the increase in cable thickness is prevented due to the increase in capacity as the capacity increases. When high tensile strength is required and cold resistance and flexibility are required. The structure of the outer covering material 10 of the duct by this is shown in FIG.

Referring to FIG. 13, the sheet-shaped outer covering material 10 includes five layers, and the five layers include the outer layer 12, the first inner layer 14, the metal layer 16, the second inner layer 18, and the third inner layer ( 19), the outer layer 12 is high density polyethylene, the first inner layer 14 is polyethylene vinyl alcohol, the metal layer 16 is aluminum, the second inner layer 18 is nylon 6, the third inner layer 19 ) Consists of a high density polyethylene containing 7% polysilicon oil.

In addition, the adhesive resin 13 for adhering the outer layer 12 and the first inner layer 14 is an adhesive resin 15 for adhering the anhydride-modified polyethylene vinyl acetate, the first inner layer 14, and the metal layer 16. The adhesive resin 17 for adhering the acrylic resin or the styrene copolymer resin, the metal layer 16 and the second inner layer 18 is a maleic anhydride styrene ethylene copolymer, the second inner layer 18 and the third inner layer 19 ) Is an anhydride-modified polyethylenevinylacetate.

The outer covering 10 has a thickness of 0.5 mm and a total thickness of 2.5 mm, and can be freely produced, including biaxial stretching, by simple heating calender casting, and the production cost is low.

As such, the present invention has made it possible to produce a multilayer structure of a duct which is very difficult or inefficient to produce with a conventional tubular coextrusion method at low cost without complicated device facilities.

Next, a method of fixing the plurality of primary tubes 20 to the sheet-like outer cladding 10 will be described.

In order to maintain the desired uniform formulation of the sheet-shaped outer cladding 10 and the plurality of primary tubes 20, the duct 30 must be firmly coupled to maintain its shape during the installation, as well as maintenance thereafter. There should be no destruction of properties even when detached for

The methods for this purpose can be broadly classified into four types: 1) adhesion of physical, physical-chemical and chemical methods, 2) adhesives and adhesive tapes, 3) adhesive resins such as hot melts, and 4) heat fusion and co-substitution. Permanent bonding, such as bonding.

In addition, in addition to maintaining a constant form at the time of installation, in order to overcome the contraction and relaxation caused by changes in external temperature, and to withstand a long time after installation must maintain a certain bonding force.

Moreover, the outer covering 10 in the form of cotton and the primary tube 20 in the form of lines have different shrinkage and relaxation moments, which are more important. When the material of the outer coating material 10 and the primary tube 20 is not the same, or even if the content of the inorganic and organic additives added for heat resistance, flame retardancy, etc., even if the same type, the separation phenomenon due to shrinkage relaxation Appears badly.

To overcome this, a bond strength of 3 to 14 kgf / cm ² should be maintained. In particular, adhesives such as hardening which occur after drying should be avoided, and materials which exhibit brittleness after curing should be avoided.

Therefore, it is preferable to add at least one of styrene rubber, epoxy rubber, butadiene rubber, ethylene rubber, urethane rubber, and ethylene-vinyl acetate copolymer-based elastic resin to 0-30% of the base polymer by weight ratio. . If the temperature difference is a gentle external environment, it can be used without adding them.

The base polymer of the adhesive, the pressure-sensitive adhesive, and the adhesive resin is the same as the material for bonding the respective layers of the outer coating material 10 of the multilayer structure, but there are differences depending on the manufacturing process.

This is a face-to-face, non-face-to-face adhesion at the time of manufacture, and most of the maintenance-related ones are not permanent bonds, there is a partial bond area, and compatibility with elastomers or rubbers used as reaction modifiers should be considered. Because.

Therefore, the base polymer of the adhesive resin for fixing the primary tube 20 to the outer coating material 10 is acrylic, olefin, olefin (hot melt), urethane, urethane (emulsion), ether cellulose, ethylene-vinyl acetate resin (Emulsion), ethylene-vinyl acetate resin (hot melt), epoxy type, epoxy type (emulsion), vinyl acetate resin (emulsion), chloroprene rubber type, cyanoacrylate type, silicone type, modified silicone type, aqueous polymer-isocyanate type, styrene Butadiene rubber, styrene-butadiene rubber (latex), nitrile rubber, nitrocellulose, polyamide (hot melt), polyvinyl acetate resin (solvent type), polystyrene resin (solvent type), polyvinyl alcohol system, polyvinyl buty At least one selected from the group consisting of Lal, melamine and urea resins is preferred.

Due to the problem caused by the change of the existing tubular outer cladding 40 to the sheet outer cladding 10 of the present invention, when the sheet outer cladding 10 is bonded to the primary tube 20, an adhesive, pressure-sensitive adhesive, or tape There is a heat shrinkage phenomenon in which the outer covering 10 is warped in the connection part of the drying, curing or heat fusion process.

This phenomenon is conspicuous when the outer sheath 10 is made thin because the outer sheath 10 does not need to be made thicker than necessary to make the low-capacity duct 30 having a small number of primary tubes 20.

In order to prevent this phenomenon, it is necessary to reinforce the heat resistance and shrinkage resistance to the outer coating material 10, and for this purpose, an additive, a modifier, or the like must be added.

In the tube type produced by co-extrusion at one time, if the property variable of one layer is changed in the whole process, the whole production process may be modified, the standard may be reset, or the speed and amount of co-extrusion constituting each layer may be changed at once. This is very difficult because it must be consistently controlled, resulting in increased process costs and rejects, increased finished product failure rates, and the addition and increase of equipment.

On the other hand, the sheet type of the present invention can produce each layer independently, or can be produced by reducing the number of co-extrusion (T-die line is used to produce two layers separately, or three layers after film casting heat Fusion and biaxial stretching), control parameters for material properties are much less.

In order to solve the above phenomenon, the base polymer of the sheet-type outer cladding 10 is a polyolefin (high density polyethylene, low density polyethylene, linear low density polyethylene, polypropylene, etc.), polyethylene vinyl acetate, polyethylene vinyl alcohol, used in the above-described single layer outer coating material. , Polyamides (nylon 6, nylon 66, nylon 12, etc.) and polyethylene terephthalate should be used, but base polymers having a melt flow index of 10-25% lower than the base polymer used in the single layer outer cladding should be selected. do. This is because the melt flow rate is significantly lowered when the heat resistant and shrinkage strengthening additive is contained.

The heat and shrinkage strengthening additives are as follows.

(1) A crosslinking agent capable of crosslinking the base polymer of the outer covering material 10 (crosslinking agent capable of introducing peroxide-based chelate functional groups, etc.)

(2) Additives to increase the heat resistance and hardness (including Rockwell hardness, Moss hardness, etc.), Vicat softening temperature, acicular wollastonite (CaSiO ₃ ), talc, mica, CaCO ₃ , metal salt (Fe ₂ O ₃ , Magnesium whisker (MgSO ₄ )), Na-Al-Si ₂ O ₆ , BaSO ₄ , SiO _{2 ,} molybdenum oxide or molybdenum powder, clay, white carbon (Si-C) to select at least one of 5 ~ 45 It is prepared by adding%.

The particle size of the additive at this time is preferably 500 to 100,000 mesh (50 μm to sub μm 1) for internal dispersion (particle dispersion). The particle shape should be as spherical as possible, and lighter weight (with pores) is more effective.

At this time, the temperature at the time of manufacturing the sheet-type outer cladding 10 should be increased by 2 to 5 ° C. according to the type of the additive per 10% of the additive, depending on the amount of the additive, and the temperature at the time of bonding with the primary tube 20 changes. There is no

(3) In order to strengthen the heat resistance and shrinkage resistance of the organic system, there is a method of increasing the molecular weight by adding an ultra high molecular weight participant (e.g., HDPE powder having a molecular weight of 2 million or more, V-PET (ultra high molecular weight PET))

14 shows a state of a general base polymer, and ② shows a polymer matrix (morphology) after strengthening.

Next, the problem of satisfying the flame retardant standards required or strengthened in the optical network market and international standards will be described.

It is much more competitive to flame retardant material in the sheet form of the present invention than conventional tubular form and is advantageous in terms of physical properties. This is because the number of variables in the sheet production process at the time of addition of additives is smaller than that of conventional coextrusion tubes.

Various methods have been developed and applied to make existing tubular ducts from flame retardant materials. However, in order to impart flame retardancy to the sheet-like outer cladding 10 of the present invention, that is, to impart flame retardancy while maintaining flexibility and luster flexibility, which are general characteristics of the optical network duct 30, material cost and economical efficiency There is a problem that is not easy.

Particularly, due to the regulation of halogen flame retardants and non-phosphorus flame retardants, which are becoming more important in recent years, more difficult compounding techniques are needed. In the present invention, but prepared using a non-halogen-based flame retardant, it was developed to differentiate from the existing in terms of cost.

Specifically, in the conventional coextrusion tube type, the application of the non-halogen flame retardant has resulted in the reduction of the existing physical properties (particularly the decrease in tensile strength and flexibility), but the problem has been solved in the sheet type of the present invention.

There are two following methods for imparting flame retardancy to the sheet-like outer covering material of the present invention.

(1) Silane or ethane oxide is added to the base polymer of the outer coating material 10 as an organic flame retardant. Silane is widely used as a coupling agent for polymers, and in the present invention, the silane was selected as one of the most suitable methods for the form of a sheet having a large surface area using this property. This increases the manufacturing cost, but promotes oxidation at the end of the polymer and rapidly carbonizes, and flame retardation is realized without seriously reducing the flexibility and tensile strength.

In order to realize the flame retardant grade Vo or V1 based on UL, at least one of polyolefin, polyethylene vinyl acetate, polyethylene vinyl alcohol, polyamide (nylon 6, nylon 66, nylon 12, etc.) and polyethylene terephthalate is used as the base polymer of the outer coating material. 1-15% of silane (methyltrimethoxysilane, tetraethoxysilane) or ethane oxide is used.

At this time, antimony trioxide powder or melamine-based powder is added according to the use as a flame retardant adjuvant. The use of flame retardant aids should not exceed 10%, given their flexibility.

(2) Inorganic flame retardants are designed in the most economical way as non-halogen flame retardants in the present invention. This was not applicable to existing coextruded tubular ducts. When the inorganic flame retardant is used in the existing tubular duct, the flexibility is severely degraded, resulting in an additional cost due to the increased storage capacity of the duct. In addition, there is a problem that the load of the extruder increases during co-extrusion, the speed is lowered, difficulty in producing the multilayer structure, the tensile strength is severely lowered, and there is no way to compensate for this.

However, in the sheet form of the present invention, because of the sheet form, the problem of flexibility is relatively reduced, and problems such as tensile strength can be easily complemented and applied in the multilayer structure.

As the base polymer of the outer coating material 10, at least one of polyolefin, polyethylene vinyl acetate, polyethylene vinyl alcohol, polyamide (nylon 6, nylon 66, nylon 12, etc.) and polyethylene terephthalate is used, and MgOH ₂ , Al is used as the inorganic flame retardant. At least one of ₂ OH ₃ and Sb ₂ O ₃ is selected, 25-60 phrs (22-57% by weight) of the base polymer is added thereto, and a low-temperature graft polymerization is performed at 150-250 ° C.

At this time, in order to increase dispersion and prevent oxidation, a lubricant (outer lubricant: PE or PP wax; inner lubricant: Zn-stearate, Ca-stearate, Zn / Ca-stearate, etc.) may be used as a primary agent. 0.1 to 5% is added, and 0.1 to 3% of MgO etc. are added as a secondary antioxidant, and it is manufactured.

In addition, when flexibility modification is required, at least one of TPX series, butadiene rubber, styrene rubber, butadiene-styrene rubber, ethylene rubber, and ethylene-styrene rubber having elasticity is modified by adding 2-10% of the base polymer. In this case, a silicone oil (synthetic silicone oil), a white oil, a mineral oil (petroleum paraffin oil) and a polymer coupling agent are used as a compatibilizer.

The fibrous structure 9 can be applied to the sheet-like outer covering material 10 of the present invention (FIG. 15).

When the functional fiber structure 9 is applied to the single-layer or multi-layer outer cladding 10, physical properties such as tensile strength can be efficiently and dramatically improved in the optical network duct 30.

Applying the fibrous structure 9 to the sheet does not require consideration of kneading and bonding properties with the resin due to the impregnated effect (if the bonding property is good, it goes without saying that the physical properties are better). It can be applied in various ways.

Examples of the fibrous structure 9 to be applied include cotton yarn and polymer fibers (including polyethylene, polyethylene terephthalate, nylon, and the like). Special purpose fiber structures include aramid fibers (high strength fibers substituted with two phenyl groups in nylon) applied to military optical communication networks and the like, and fibers, filaments, and fabrics made of polyethylene having a molecular weight of 2 million or more. Applying them improves the tensile strength several times to several hundred times.

Although the present invention described above has been described in detail only with respect to the specific examples described, it will be apparent to those skilled in the art that various modifications and variations are possible within the technical scope of the present invention, and such modifications and modifications belong to the appended claims. .

2: air blown cable 10, 40: outer covering material
12: outer layer 14: inner layer, first inner layer
16: metal layer 18: second inner layer
19: third inner layer 20: primary tube
30, 50: optical network duct

Claims (21)

In the optical network duct including a primary tube into which the optical cable is inserted, which is installed on the ground, underground or undersea,
After arranging and fixing a plurality of primary tubes in parallel to the sheet-like outer cladding, make the sheet-like outer cladding on which the plurality of primary tubes are fixed so that the plurality of primary tubes are located inside, and then attaching both ends of the sheet-like outer cladding Optical communication network duct formed of a sheet-like outer cladding material, characterized in that formed by. The method of claim 1,
And a base polymer used for the outer covering material is at least one selected from the group consisting of polyolefins, polyethylene vinyl acetates, polyethylene vinyl alcohols, polyamides and polyethylene terephthalates. The method of claim 2,
And an additive used in the outer covering material is at least one selected from the group consisting of CaCO ₃ , BaSO ₄ , talc, SiO _{2 ,} molybdenum clay and silicone oil. The method of claim 3,
At least one antistatic agent selected from the group consisting of metal or metal salt carbon, MgO, graphene, carbon nanotubes, H-BN, ZnO, Al ₂ O ₃ , AlN and SiC is further added. Optical network duct formed of sheath. The method of claim 1,
An optical communication network duct formed of a sheet type outer cover material, wherein the sheet type outer cover material comprises a plurality of layers. The method of claim 5,
The sheet-like outer covering material is composed of two layers, an outer layer and an inner layer,
The base polymer used for the outer layer is a polyolefin, the base polymer used for the inner layer is polyethylene vinyl acetate or polyamide, and the adhesive resin for bonding both layers is polyethylene vinyl alcohol, wherein the optical communication network formed of the sheet type outer coating material duct. The method of claim 1,
The sheet-shaped outer covering material is composed of three layers,
The three layers are configured in the order of the outer layer, the inner layer, the metal layer,
The base polymer used in the outer layer and the inner layer is at least one selected from the group consisting of polyolefin, polyethylene vinyl acetate, polyethylene vinyl alcohol, polyamide and polyethylene terephthalate,
And a material of the metal layer is at least one selected from the group consisting of aluminum, iron, and magnesium. The method of claim 7, wherein
Adhesive resin for adhering the outer layer and inner layer, inner layer and metal layer is acrylic, acrylic (anaerobic), olefin, olefin (hot melt), urethane, urethane (emulsion), ether cellulose, ethylene-vinyl acetate resin (emulsion) , Ethylene-vinyl acetate resin (hot melt), epoxy type, epoxy type (emulsion), vinyl chloride resin (solvent type), vinyl acetate resin (emulsion), chloroprene rubber type, cyanoacrylate type, silicone type, modified silicone type, aqueous polymer -Isocyanate type, styrene-butadiene rubber, styrene-butadiene rubber (latex), nitrile rubber, nitrocellulose type, polyamide type (hot melt), polyimide type, polyvinyl acetate resin (solvent type), polystyrene resin (solvent type) Polyvinyl alcohol, polyvinylpyrrolidone, polyvinyl butyral, polybenzimidazole, polymethacrylate (solvent type), melamine resin, urea resin, and An optical communication network duct formed of a sheet-like outer coating material, characterized in that at least one selected from the group consisting of resorcinol. The method of claim 8,
In the group consisting of CaCO ₃ , BaSO ₄ , talc, SiO _{2 ,} Al ₂ O ₃ , Al (OH) ₃ , Mg (OH) ₂ , molybdenum, molybdenum oxide, carbon, carbon nanotubes and MgO as additives to the adhesive resin An optical network duct formed of a sheet-like outer cladding, characterized in that at least one selected is added. The method of claim 7, wherein
The material of the inner layer is polyolefin or polyamide,
And an adhesive resin for adhering the inner layer and the metal layer comprises maleic anhydride and peroxide in addition to the base polymer. The method of claim 1,
The sheet-shaped outer covering material is composed of five layers,
The five layers are configured in the order of the outer layer, the first inner layer, the metal layer, the second inner layer, the third inner layer,
The optical communication network formed of a sheet type outer coating material, wherein the outer layer is made of high density polyethylene, the first inner layer is polyethylene vinyl alcohol, the metal layer is aluminum, the second inner layer is nylon 6, and the third inner layer is made of high density polyethylene containing polysilicon oil. duct. The method of claim 11,
The adhesive resin for bonding the anhydride-modified polyethylene vinyl acetate, the first inner layer and the metal layer to the adhesive resin for bonding the outer layer and the first inner layer is an adhesive resin for bonding the acrylic resin or the styrene-based copolymer resin, the metal layer and the second layer. An optical communication network duct formed of a sheet type outer coating material, wherein the adhesive resin for adhering the maleic anhydride styrene ethylene copolymer, the second inner layer and the third inner layer is an anhydride-modified polyethylenevinylacetate. The method of claim 1,
And the fixing of the primary tube to the sheet-shaped outer coating material is adhesion by an adhesive resin. The method of claim 13,
The base polymer of the adhesive resin is acrylic, olefin, olefin (hot melt), urethane, urethane (emulsion), ether cellulose, ethylene-vinyl acetate resin (emulsion), ethylene-vinyl acetate resin (hot melt), epoxy, Epoxy type (emulsion), vinyl acetate resin (emulsion), chloroprene rubber type, cyanoacrylate type, silicone type, modified silicone type, aqueous polymer-isocyanate type, styrene-butadiene rubber, styrene-butadiene rubber (latex), nitrile rubber, nitro At least one selected from the group consisting of cellulose, polyamide (hot melt), polyvinyl acetate resin (solvent type), polystyrene resin (solvent type), polyvinyl alcohol system, polyvinyl butyral system, melamine resin system and urea resin system An optical communication network duct formed of a sheet-like outer covering material, characterized in that. The method of claim 14,
At least one selected from the group consisting of styrene rubber, epoxy rubber, butadiene rubber, ethylene rubber, urethane rubber, and ethylene-vinyl acetate copolymer-based elastic resin is added to the adhesive resin. duct. The method of claim 2,
The optical communication network duct formed from the sheet | seat type outer cladding material characterized by the additive used for the said outer cladding material being a crosslinking agent which can bridge | crosslink the said base polymer. The method of claim 2,
The additive used in the outer coating material is at least one selected from the group consisting of CaSiO ₃ , Fe ₂ O ₃ , MgSO ₄ , Na-Al-Si ₂ O ₆ , clay and Si-C as a sheet type outer coating material Formed optical network duct. The method of claim 2,
An optical communication network duct formed of a sheet-type outer coating material, characterized in that the additive used for the outer coating material is a high-density polyethylene powder of 2 million or more molecular weight or ultra high molecular polyethylene terephthalate of 2 million or more molecular weight. The method of claim 2,
And an silane or ethane oxide as a flame retardant to the outer coating material. The method of claim 2,
And an at least one of MgOH ₂ , Al ₂ OH ₃ and Sb ₂ O ₃ as a flame retardant to the outer coating material. The method of claim 1,
An optical communication network duct formed of a sheet-like outer cladding material, wherein the sheet-like outer cladding material is impregnated with a fiber structure.

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