JPS5940603A - Material for forming organic thin film for optical fiber - Google Patents

Abstract

PURPOSE:To enhance joint strength by leaps and bounds, by using a thin film forming material made of a synthetic resin contg. chlorine in order to weld and connect optical fibers. CONSTITUTION:The present thin film forming material made of a synthetic resin contg. chlorine, is prepared by two kinds of methods (A) using a monomer for forming said resin contg. chlorine in the skeleton of the monomer, and (B) using a resin compsn. obtd. by adding a chlorinated org. compd. to a resin contg. no chlorine. For example, in the case of (A), a monomer for forming said resin, such as epoxy, urethane, polyester, or polyamide resin, contg. chlorine in the skeleton of the monomer is used, and in the case of (B), a resin compsn. prepd. by adding chlorinated paraffin, chlorinated polyphenyl, or the like chlorinated compd. to said epoxy resin contg. no chlorine is used.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field The present invention relates to an organic thin film forming material for optical fibers, which is suitable for optical fibers to be fusion spliced.

(b) Background Art When installing optical fiber cables, the connection of optical fibers is an important point. Methods for connecting optical fibers include a method of abutting and fixing optical fibers together and a method of fusion splicing the optical fibers themselves, and the present invention relates to the latter method.

When optical fibers are fusion spliced, the primary cover is usually removed and the optical fibers are melted and spliced by electrical discharge or the like. Problems with this type of fusion splicing include the fact that when the primary material is removed, the surface of the optical fiber is falsified, and the primary material that is not sufficiently removed becomes dust on the surface of the optical fiber, causing damage when heated. are doing. Particularly in the case of silicone resins which are primarily coated and exhibit excellent properties, a reduction in strength due to insufficient removal has become a problem.

As a countermeasure to Nana et al., a method was proposed in which an organic thin film of several micrometers was interposed on the surface of an optical fiber and the silicone removed from the thin film was removed without applying VC on the surface. Since this organic thin film vaporizes during fusion splicing, there should be no problem with the connection characteristics of the optical fiber, but even when splicing an optical fiber with this organic thin film, the splicing strength is about 115 that of the original optical fiber. It just turned out to be. The location of the break is near the connection point, and it cannot be considered that L1 is a flaw caused when the primary coating is removed, as in the conventional case, but is considered to be caused by an essential problem of such fusion splicing.

On the other hand, it is known that using a chlorine gas atmosphere during fusion splicing increases the strength of the connection, and this is thought to be due to suppressing the growth of defects that occur on the optical fiber surface due to moisture. . However, although excellent connection strength can be obtained by fusion splicing in a carbon gas atmosphere, it is too dangerous for practical use.

(C) Disclosure of the Invention The inventors of the present invention have conducted independent research on a method for easily obtaining excellent connection strength through fusion splicing, and the result is an optical fiber that has been developed using an organic thin film containing chlorine atoms. t-#J
It was discovered that the connection strength was dramatically improved when the connection was made on the right, and the present invention was achieved.

The present invention consists of a synthetic tree 11ir containing chlorine atoms,
Regarding organic thin film forming materials for coating on the surface of optical fibers, synthetic resins containing chlorine atoms include 0) those containing chlorine atoms in the skeleton of the monomer forming the resin, and ■ chlorine atoms. There are two types: one is a resin composition in which a chlorinated organic compound is added to a resin that does not contain chlorinated organic compounds.

■ Examples of binders include those containing chlorine atoms in the skeleton of resin-forming monomers such as epoxy resins, urethane resins, polyester resins, polyamides, polybutadiene resins, and acrylic resins. Examples include the epoxy resin of (1) and the urethane resin of formula (II).

An example of ■ is a resin composition made by adding a salt water-based compound such as chlorinated paraffin, chlorinated polyphenyl, or perchloropentacyclodecane to a resin such as the above-mentioned epoxy resin that does not contain a chlorine atom. Can be mentioned.

The content of chlorine atoms must be at least 5% by weight, and the thickness of the thin film is preferably in the range of #'i1 to 20 pm.

Such an organic thin B! Chlorine radicals are generated by heating the optical fiber coated with A with electric discharge, and the same effect as fusion splicing in a salt water gas atmosphere can be obtained.

B) Best Mode for Carrying Out the Invention Example 1 An optical fiber is drawn to a thickness of 125 μm, and (a) an epoxy resin shown in formula (1) is coated on the fiber to a thickness of 5 μm, (b) ) 400% silicone resin on top of (a)
(C) An epoxy resin that does not contain chlorine atoms is coated on the fiber with a wave phase of 5 μm, (d) A chlorine atom is applied to the fiber to have an outer diameter of 20% of chlorinated paraffin in epoxy resin that does not contain
A mixture of heavy densified silicone and a 5 μm thick coating on the fiber, (2) silicone resin on the fiber with a thickness of 400 μm
Five types of strands were manufactured which were coated to the outer diameter.

(a), (Q), (d) remain as is, (b), (θ>F
i The silicone was peeled off with gauze and fusion spliced by electrical discharge. The average strength of these connections is (a) Fi
a K, F, (b) #1xa4, (C) is 1hs (d
) is 57-1(6) is (L 5 K9 and request Matta.

It can be seen that the strength of the L-side connection is increased due to the effects of prevention of surface scratches by the organic thin film and removal of moisture by the chlorine atoms.

(b) is slightly smaller than (a) because the silicone has not been completely removed. This is thought to be due to the presence of a portion that does not clear, or the presence of vinyl poles in the epoxy film due to imperfections in the Fi manufacturing conditions.

Agent: 1) Akira Agent Ryo Hagi Hara -

Claims (1)

[Claims] An organic thin film-forming material made of synthetic resin containing chlorine atoms and used to coat the surface of optical fibers.