JPS59171905A - Fiber for infrared light - Google Patents

Abstract

PURPOSE:To improve the ease of operation and durability of a fiber by providing a pipe-shaped protective layer on the outside of a crystalline fiber composed of the mixed crystals formed by adding a specified amt. of silver chloride to silver bromide or silver bromide to silver chloride. CONSTITUTION:The refractive index of the mixed crystals formed by adding 0.01-10wt% silver chloride to silver bromide with 10.6mum light is about 2.1, and the refractive index of the mixed crystals formed by adding 0.01-10wt% silver bromide to silver chloride with 10.6mum light is about 2. The mixed crystal fiber having such compsn. region is put into a pipe-shaped protective layer 3 using a porous plastic or the like and the mixed crystals of the former are used as a core part 1 and the mixed crystals of the latter a clad part 2, by which IR light can be quided in the core and the fiber for IR light which has high breading stress, yield stress and breaking elongation, is resistant to scratching, and has flexibility and an excellent mechanical characteristic is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an infrared fiber with excellent mechanical properties.

Various studies have been made to create fibers for infrared light by extruding optical crystals that transmit infrared light or growing fiber-shaped single crystals (Nikkei Electronics, December 8, 1980). As shown in Fig. 1, a crystalline fiber 1 is placed in a pipe-shaped protective layer 3, and the crystalline fiber is used as a core part and the gap part of the pipe is used as a cladding part 2. Alternatively, infrared light fibers having the configurations shown in FIGS. 2 and 3, such as step-index fibers for optical communications, have been considered.

Silver chloride and silver bromide have a wide wavelength transmission range, can transmit CO and laser light (wavelength 1a6 μm) with low loss, and are suitable as materials for infrared light.

Infrared light fiber using silver halide crystal was published in Japanese Patent Application Laid-open No. 1986-
As disclosed in Japanese Patent No. 121,406, US Pat. No. 4,255,731, etc., step-index fibers are known in which silver halide optical hexagonal crystals are extruded, with a crund of silver chloride and a core of silver bromide. however,
When attempting to produce an infrared fiber using a combination of silver chloride and silver bromide, the breaking stress and yield stress are small, and when performing operations such as extrusion processing or bending the produced fiber, the fiber The disadvantage is that the surface is easily damaged or broken. This disadvantage becomes more pronounced when impurities in the fiber material are removed in order to reduce optical transmission loss.

On the other hand, in JP-A-55124105, the core part is made of silver bromide or a molten mixture of silver bromide and silver chloride, and the clad part is made of bromide at a lower silver bromide content than the core part. A mixture of bromide and silver chloride of up to 50 mol %, especially a mixture of bromide and silver chloride, is described, especially from the viewpoint of transmission characteristics. A mixture containing 5 to 30 moles of silver oxide is mentioned. In this case, the breaking stress and yield stress become large, but the breaking elongation becomes significantly small, and the fiber becomes hard and brittle, and has the drawback of being easily broken by operations such as bending.

The present invention investigates a mixed crystal composition with large breaking stress, yield stress, and breaking elongation in an infrared-filled fiber using a silver/ride such as silver chloride and silver bromide, and improves the operability and durability of the fiber. It is calculated by

Next, the results of a study on the mechanical properties of a silver bromide-silver chloride mixed crystal will be shown.

After arbitrarily mixing silver chloride and silver bromide powders, they were melted at 480°C and crystallized by the Bridgman method.

This crystal was solution-treated at 400° C. for 24 hours to produce a mixed crystal with a uniform composition. These crystals of various compositions were hot extruded at an extrusion temperature of 180 DEG to 350 DEG C. to produce fibers having a diameter of .alpha.1 to 1.5 .phi.. The fibers were subjected to a tensile test. The results are shown in FIG. As can be seen from FIG. 4, by adding a small amount of silver bromide to silver chloride, and by adding a small amount of silver chloride to silver bromide, the yield stress, breaking stress, and breaking elongation become thicker, and empirically, 0. A positive effect was observed by adding 01 weight ratio. Specifically, a mixed crystal in which 0.01 to 10% by weight of silver bromide is added to silver chloride, or a mixed crystal in which 0.01 to 1% by weight of silver bromide is added to silver bromide.
It was found for the first time that the mixed crystal containing 0% by weight silver chloride has a satisfactory range of breaking stress, yield stress, and breaking elongation.

In addition, the elongation at break of another sample manufactured in the same manner as above (
As shown in Table 1 Sandals No. 1 to 14, silver bromide contains 1
The elongation at break of a mixed crystal fiber with silver chloride added to 0% by weight and a mixed crystal fiber with silver bromide added to silver chloride up to 10% by weight corresponds to the elongation at break of a fiber consisting only of silver bromide or silver chloride. We were able to obtain a mechanically stable fiber that exhibited an elongation at break of 200 nm or more.

Among them, mixed crystal fibers in which up to 10% by weight of silver bromide is added to silver chloride and mixed crystal fibers in which up to 5% by weight of silver chloride is added to silver bromide have excellent elongation at break. Mixed crystal fiber with silver bromide added to 01 to 5% by weight, and mixed crystal fiber with silver chloride added to silver bromide to 1 to 5% by weight, and furthermore, 1 to 5 weight% of silver chloride.
Mixed crystal fibers doped with silver bromide up to 1% and silver bromide doped with 1
It can be seen from Table 1 that the mixed crystal fibers doped with silver chloride up to 55% by weight are significantly superior in elongation at break.

Liquid crystal fibers with these compositions are more resistant to scratches and have better flexibility than fibers with a single silver bromide composition, and they are less likely to be scratched than fibers with a higher amount of additives than mixed crystal fibers. We were able to obtain a mechanically stable fiber with no brittleness.

Therefore, as shown in Figure 1, by placing a mixed crystal fiber in this composition range in a pipe-shaped protective layer, with the crystal part as the core part 1 and the gap between the pipe and the clad part 2, excellent mechanical properties can be achieved. We were able to obtain a fiber for infrared light.

This pipe-shaped protective layer may be made of soft, porous plastic or rubber that acts as a cushioning material, such as polyurethane, polystyrene, ABS resin, polyvinyl chloride, etc.
Polyethylene, polypropylene, phenolic, silicone, urea, and fluororesin pipes can be used. Furthermore, if necessary, the pipe may be further coated with waterproof dense plastic or rubber (eg, ABS resin, polybutadiene, polypropylene, polycarbonate, polyvinyl chloride, polyphenylene oxide, polysulfone, or a mixture thereof). Melt extrusion or polyesterimide, polyester, polyurethane, polyol, polyimide,
It can be coated by coating and baking polyamideimide, silicone resin, tetrafluoride resin, epoxy resin, or a mixture thereof.

It is also effective to use a heat-shrinkable pipe as the coating layer used for the exterior. For example, polyethylene, polyvinyl chloride, polyethylene, polyvinyl acetate copolymer, chlorinated polyethylene, polyvinylidene fluoride, etc. can be used. If necessary, the resin may be coated singly or in multiple layers.

On the other hand, as a protective layer, the plastic or rubber coated on the buffer layer, which is the pipe protective layer, can be directly coated on the cladding material, either singly or in multiple layers.

In addition, the refractive index at 10.6 μm light of a mixed crystal obtained by adding 0.01 to 10% by weight of silver chloride to silver bromide is around 2.1. mixed crystal'
i El The refractive index at 6 μm is around 2, and by using the former mixed crystal as the core part 1 and the latter mixed crystal as the cladding part 2, it is possible to guide infrared light into the core, and the breaking stress can be reduced. The yield stress and elongation at break were as large as those of the mixed crystal, and it was possible to obtain fcQ external optical fibers with excellent mechanical properties as shown in FIGS. 2 and 5, which were scratch resistant and flexible. This infrared light fiber has large breaking stress and breaking elongation even when subjected to bending that causes plastic deformation, is resistant to repeated bending, and is mechanically stable.

In the above combination of core part and crund part, silver bromide contains 1
A core made of a mixed crystal containing silver chloride in an amount of 55% by weight and a cladding made of a mixed crystal containing 1 to 5% by weight of silver bromide in silver chloride has excellent properties.

The infrared light fiber of the present invention can be used to connect to a 002 or CO laser light guide path of a laser treatment device such as a laser scalpel or laser coagulator (coagulator), or to an infrared detector such as a remote alarm. Can be used for infrared light guide.

Example 1 High purity silver chloride and silver bromide powders were mixed at a weight ratio of 99:1, and cylindrical crystals were produced by the Bridgman method. This crystal was solution-treated at a temperature of 350 to 410° C. for 24 hours to produce a mixed crystal with a uniform composition. This crystal was extruded into a billet, the billet and extrusion mold were heated with an external heater, and hot extrusion was carried out at an extrusion temperature range of 100 to 580°C to produce a fiber with a diameter of 15 to 1.5 mm.

Example 2 High-purity silver chloride and silver bromide powders were mixed at a weight ratio of 2=98, cylindrical crystals were produced by the Bridgman method, and hot extruded under the same conditions as in Example 1. Fibers with a diameter of 5 to 1.5 mm were fabricated.

The crystalline fibers of Examples 1 and 2 thus obtained were flexible fibers that were not easily damaged, and were loosely inserted into a resin pipe to form infrared light fibers.

Example 3 The ready-made mixed crystal columnar crystal of Example 2 and the mixed crystal pipe-shaped crystal of the composition of Example 1 are produced and fitted together to form a billet for extrusion. This crystal was hot extruded under the same conditions as in Example 1 to produce a fiber having a diameter of 0.5 to 1.5. The mixed crystal with the composition of Example 2 becomes the core part, and the mixed crystal with the composition of Example 1 forms the cladding part, and this step-index fiber is resistant to scratches like the fibers of Examples 1 and 2.
<, a flexible fiber.

In the crystalline fiber of Example 5, since light is guided to the core part 1 by the cladding part 2, the infrared light is It was used as a fiber for use.

Infrared fiber f 2 m obtained as above
A CO2 gas laser beam (wavelength 1α6 μm) with an output of 1 OW is input into one end, the laser beam is emitted from the other end, and the light is focused using an infrared focusing lens such as all-zinc selenide. When a hole is made in a plastic plate such as an acrylic plate or wood, or when it is cut, a tip is created.

[Brief explanation of the drawing]

1 to 5 are cross-sectional views of infrared light or optical fibers, and FIG. 4 is a graph showing the relationship between the mixed crystal composition and mechanical properties of a silver bromide-silver chloride mixed crystal fiber. Agents 1) Akira Agent Ryo Hagiwara - Figure 1 Figure 2 Figure 3

Claims (1)

[Scope of Claims] 1. An infrared light transmitting compound consisting of a mixed crystal obtained by adding 101 to 10% by weight of silver chloride to silver bromide, or a mixed crystal obtained by adding 1101 to 10% by weight of silver bromide to silver chloride. material. 2. A pipe-shaped fiber is formed on the outer periphery of a crystalline fiber made of a mixed crystal in which 0.01 to 10% by weight of silver chloride is added to silver bromide, or a mixed crystal in which 0.01 to 10% by weight of silver bromide is added to silver chloride. Infrared fiber with a protective layer. & Consisting of a core part and a cladding part, or a core part, a cladding part, and a protective layer covering the outer periphery, the core part is coated with silver bromide at 10%.
An infrared light fiber made of a material selected from a mixed crystal containing silver chloride in an amount of up to 10% by weight, and a mixed crystal in which the cladding part contains silver chloride and silver bromide in an amount of up to 10% by weight. 4. The silver chloride concentration in the core part is α01 to IO% by weight, and the silver bromide concentration in the cladding part is 0.01 to 10% by weight.
An infrared fiber according to claim 6.