JPS6033520A - Fiber-reinforced optical fiber and its manufacture - Google Patents

Abstract

PURPOSE:To prevent the fracture, microbending, etc., of an element wire and to improve flexure characteristics by bringing a fiber-reinforced resin layer formed around the outer circumference of the element wire and a thermoplastic resin coating layer arranged around its outer circumference into contact integrally by anchor effect. CONSTITUTION:The layer 22 of the fiber-reinforced thermosetting resin (FRP) is formed around the outer circumference of the optical fiber element wire 2, and the layer 8 of thermoplastic resin (TP) is arranged around the outer circumference of the FRP layer 22; and the coating layer 8 and FRP layer 22 are brought into contact integrally by the anchor effect. Namely, a reinforcing fiber bundle 4 impregnated with thermosetting resin (TR) in an unset state is arranged around the outer circumference of the element wire 2 and coated with TP, and then a heat treatment is carried out after temporary cooling to bring the FRP layer 22 and TP layer 8 into contact integrally by the anchor effect simultaneously with the setting of the TS. Consequently, the TP layer 8 serves as a die which sets the internal FRP layer 22 while holding it in a specific shape, and prevents the breaking of the wire by protecting the element wire 2 against high tensile force. Further, the FRP layer 22 and TP layer are brought into contact by the heat treatment to improve the flexure characteristics and to increase the coating speed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a 4JIi navy blue reinforced optical fiber and a method of manufacturing the same.

Conventionally, this is a reinforced fiber bundle in which the outer periphery of an optical fiber is formed by first coating the core and cladding made of quartz glass, etc., and then applying a buffer layer of silicone, etc. to the outer periphery of the optical fiber, which is bound and integrated with thermosetting resin. A fiber reinforced optical fiber coated with is known.

A general manufacturing method for fiber-reinforced optical fibers as described above is to cover the outer periphery of an optical fiber with a reinforcing fiber bundle impregnated with an uncured thermosetting resin, and then heat-form the fiber through a thermoforming die. The thermosetting resin is completely cured as it is passed through and pulled out. However, in the above J: eel manufacturing method, the reinforcement 11i1 impregnated with an uncured thermosetting resin
When the 1f bundle passes through the die, the thermosetting resin hardens from an uncured state to a solid state, and the friction between the die wall surface and reinforcing fibers also changes due to a significant change in the viscosity of the thermosetting resin at that time. As a result, the reinforcing IM 11 bundle moved within the molding die, deforming the soft silicon layer of the optical fiber strand, and causing micro-bent, etc., which caused a reduction in transmission loss. In addition, for a certain length of the molding die, there is friction between the hardened thermosetting resin and the wall of the die, so the tension between the molding die and the pulling machine increases and the tension exceeds the allowable range. There was a risk of breaking the central optical fiber. Furthermore, the length of the die is also bad because it takes a relatively long time for the thermosetting resin to harden, so the die is long and loud.

The present invention has been made in view of the above-mentioned deficiencies of the prior art.The purpose of the present invention is to provide a microphone 1-
In the past, thermosetting 1 (1 resin layer and its outer periphery coating thermoplastic resin) was formed around the optical fiber cable. An object of the present invention is to provide a finely reinforced optical fiber which is integrally bound by an anchor effect and has excellent bending properties FLR, and a method for manufacturing such a fiber reinforced dark blue optical fiber extremely efficiently.

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

First, the method of the present invention will be explained with reference to FIGS. 1 and 2. An optical fiber 2 is continuously drawn out from a bobbin 1 and supplied. The optical fiber cable 2 is made of a wire having a core made of quartz glass or the like, a cladding, and a buffer layer coated on the core and cladding. In the above-mentioned bobbin 1, a large number of glass fiber bundles 4 are continuously drawn from another boggon 3, and the glass fiber bundles are placed in a tank 5 containing an uncured thermosetting resin, preferably an unsaturated polyester resin. The glass fiber sheath bundle 4 is then impregnated with this uncured thermosetting resin. Next, glass 1 impregnated with this uncured thermosetting resin
The 1i1F bundle 4 is shaped into a predetermined cross-sectional shape through a series of shaping rings 6, and guided to the central passage of the discharge port of the melt extruder 7 with the optical fiber cord 2 coated in the center. In this molten extruder 7, the molten thermoplastic resin 8 is discharged in the form of a discharge port that annularly surrounds the outlet of the central channel 3, and coats the glass 1IIlf bundle 4. Immediately thereafter, The thermoplastic resin 8 covering the glass fiber bundle 4 in a molten state is cooled and solidified in a cooling water tank 19 to obtain a linear object 10 in which the thermosetting resin inside has not yet hardened.

This linear material 10 is introduced into a curing tank 11, which is shown in detail in FIG. The curing tank 11 is shaped like a long and narrow pipe in the front-rear direction, and one end of the curing tank 11 has a predetermined temperature fft (100
A supply port 12 for steam pressurized at temperatures above .degree. C.) is provided, and a condensed water outlet 13 is provided at the narrow end side thereof.

Water tanks 171a and 14b are provided at both front and rear ends of this curing tank 11.
are provided, and water supply ports 15a, 15b and drain ports 16a, 16b are formed in the lower and upper sides of each water tank, respectively. The water tanks 14a, 14b and the curing tank 11 are partitioned by sheet-like elastic packings 18a, 18b having through holes 17a, 17b, and the water 4f'! 14
The front and rear sides of a and 141) are closed by other sheet-like elastic packings 19a and 19b having through holes. First, steam at a temperature of 100° C. or higher is supplied from the supply port 12 at a saturated steam pressure into the curing tank 11, and the rainwater tanks 14a, 14. b to each water supply 1115a
, supply cooling water from 15b, and drain the overflow water to υ1waterro16
a, discharge from 16b. In this state, the linear object 10 is introduced into the curing tank 11 through the through holes of the rear water tanks 14a and 14h. The temperature of the steam in this curing tank 11 is around the melting point of the thermoplastic resin 8 covering the linear material 10, for example, 140 to 150°C in the case of nylon 12, 120 to 14.0°C in the case of low density polyethylene, In the case of polypropylene, the temperature is 130 to 150°C.

Under such temperature conditions, when the curing reaction of the uncured thermosetting resin in the linear object 10 starts, the interface with the coating thermoplastic resin 8 becomes warmer than the steam temperature due to the heat generated by curing of the thermosetting resin. The temperature rises and melts the inner part of the coating thermoplastic resin at the interface of A, whereby the thermosetting ↑Il resin and the coating thermoplastic resin are firmly adhered to each other by the anchor effect under pressure.

On the other hand, the surface of the coated thermoplastic resin that is in contact with the steam is heated to tJ (heated by the steam and maintained almost like a steam hot stone, and the roundness of the surface is maintained. 10 is then introduced into the forward water PJ 14 b, and the coated thermoplastic f11 resin 8, which was in a molten state, is immediately cooled and assimilated 2).

This water tank 14b and the rear plastic side water tank 14a are the hardening tank 11.
There is also a liquid seal C to prevent the vapor pressure from escaping, and there is a water tank 141i on the front side.
also serves as a cooling tank in which the coated thermoplastic ↑1 resin 8 is cooled and solidified.

- The linear material 10 heat-treated by the sea urchin is transported to the collecting machine 2.
It is picked up, wound 2N onto a drum by 21, and then shipped.

7 of book i. The manufactured fiber-reinforced optical fiber is shown in FIG. A coating layer 8 made of a thermoplastic resin is formed on the outer periphery of the coating layer 8, and the thermosetting resin on the inside of the coating layer 8, such as the thermoplastic ↑II resin, is tightly adhered to the inner side of the thermoplastic resin due to the anchor effect. This is what happens.

As is clear from the above explanation, in the string-reinforced optical fiber according to the present invention, the string-reinforced thermosetting resin layer 22 and the coating layer 8
I, which is in close contact with each other due to the anchor effect:
Therefore, both layers integrally function as a tension member and can be covered with a fiber reinforced optical fiber having extremely excellent tensile strength and bending strength.

(g) In the method of the present invention, a reinforcing fiber sheath bundle having an optical fiber wire arranged in the center is impregnated with an uncured thermosetting resin, and then coated with a molten thermoplastic resin, and then this thermoplastic resin is coated with a molten thermoplastic resin. Because it is cooled and solidified, this solidified coating thermoplastic 1!1 resin plays the role of a die that hardens the internal thermosetting resin while maintaining it in a predetermined shape.
: There is no need for the thermosetting T11 resin to be pulled with high resistance inside the thermoforming die, making molding extremely simple, and there is no need to worry about applying high tension that could cause breakage to the internal optical fiber. do not have. Furthermore, -7 = covered with thermoplastic bamboo tree 111r assimilated into sea urchin, of which 81≦
The uncured thermosetting resin is placed in a heat treatment tank filled with heated steam, and heated at a temperature close to the melting heat of the thermoplastic resin. When the thermoplastic resin hardens, a portion of the thermoplastic resin in contact with it melts, and the two are brought into close contact due to the anchor effect, improving bending properties and eliminating the phenomenon of reinforcing fibers popping out of the surface coating resin layer. .

Furthermore, when the heat treatment is carried out under pressurized steam, it is possible to carry out the heat treatment at a comparatively low rate of 1% and at a rate 3 to 5 times faster than heat treatment using hot water.

[Brief explanation of drawings]

FIG. 1 is an overall explanatory diagram of the method for manufacturing fiber-reinforced optical fiber according to the present invention, FIG. 2 is a side sectional view showing the specific structure of the steam curing tank of FIG. 1, and FIG. FIG. 2 is a cross-sectional view showing a reinforced optical fiber. =8- 2......Optical fiber cable 4...Glass 141i 111 bundle 5...
...... Thermosetting resin layer 7 ...... Melt extruder 8 ...... Thermoplastic resin 9 ......
・・・Cold 7Jl water 11ν10・・・String material 11・・・Cured layer 22・・・Thermosetting v1 resin layer Patent applicant Ube Mezuka Kasei Co., Ltd. Agent Patent attorney Shi - Kensuke Iro

Claims (2)

[Claims] (1) Form a string-reinforced thermosetting bamboo resin layer around the outer periphery of the optical fiber wire, form a covering layer made of thermoplastic T'l resin around the outer periphery of the resin layer, and A reinforced optical fiber characterized in that a T'l resin is integrally adhered to an inner thermosetting resin and an anchor. (2) A reinforcing fiber bundle impregnated with an uncured thermosetting resin is arranged around the outer periphery of the optical fiber cable, and the outer periphery of the reinforcing mw# bundle is coated with a molten thermosetting resin by extrusion. The thermoplastic resin is immediately cooled and solidified, and then introduced into a heat treatment tank. In the heat treatment tank, steam having a temperature near the melting point of the solidified coated thermoplastic resin is applied under pressure, whereby the thermosetting resin is While accelerating the curing reaction of the resin, the coating thermoplastic resin is brought into close contact with the thermosetting ↑1 resin in a molten state at the interface, and after passing through the heat treatment tank, the coating thermoplastic resin is cooled and solidified again. A method for manufacturing a fiber-braided reinforced optical fiber.