JP2934760B2 - Polishing film for optical fiber end face polishing - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a polishing film, and more particularly, to a polishing film used for precision finish polishing of an end face of an optical fiber.

[Conventional technology]

In recent years, optical fibers have been widely used as mass communication means instead of conventional small electric wires. However, it is particularly required that the end face of the optical fiber be finished to a precise surface in order to transmit an optical signal without loss, and a high hardness inorganic fine powder is coated on a base material for a polishing film such as a film or synthetic paper. A polishing film or the like obtained by applying and drying a dispersion resin solution of an inorganic powder dispersed in a solution to form a polishing layer is used.

[Problems to be solved by the invention]

In recent years, in an optical fiber end face polishing machine for polishing an end face of an optical fiber, a polishing treatment is performed by pressing a load of about several kg / cm ² against a tip of an optical fiber-equipped connector against a polishing film. Since the film is inferior in elasticity, it is easily affected by the surface condition of the support supporting the polishing film, and the influence of the occasional occurrence of convex portions and foreign substances on the surface of the polishing film. In some cases, it is difficult to perform highly accurate polishing.

[Means for solving the problem]

The present invention has been made in order to solve the above-mentioned disadvantages, and is not affected by the surface state of the support supporting the polishing film by absorbing excessive pressure even if an excessive pressure is applied. A polishing film for polishing an end face of an optical fiber that can perform a good polishing finish and that can perform a polishing finish with high accuracy without being affected by the intrusion of a convex portion or a foreign substance sometimes generated on the surface of the polishing film. It was made for development purposes.

Therefore, as a result of studying various aspects in order to develop a polishing film having the above properties, the present inventors focused on the point that the properties of the binder component of the polishing layer are important. Furthermore, the present inventor further studied and obtained a new finding that the glass transition point is particularly important among the properties of the binder component, and made a deep study based on this new finding, thereby completing the present invention.

That is, an important feature of the present invention is that in a polishing film for polishing an end face of an optical fiber, a binder component of the polishing layer is made of a resin having a glass transition temperature of 30 ° C. or lower.

Examples of the substrate for the polishing film in the polishing film for polishing the end face of the optical fiber of the present invention include polyethylene terephthalate, polypropylene, polycarbonate, di-
Acetate acetate, tri-acetate acetate, polyethylene, polybutylene terephthalate, a resin film having excellent properties in terms of mechanical strength, dimensional stability, heat resistance, etc., with a thickness of about 12 to 150 μm, which are widely used. You.

In the present invention, a resin having a glass transition temperature of the binder component in the polishing layer of 40 ° C. or lower, preferably 30 ° C. or lower is used. Examples of the resin include a polyester resin, a polyurethane resin, and salt / vinegar. Bi-resin, polyamide resin, epoxy resin, butyral resin and the like are used.

However, as long as the resin has the above glass transition point, various resins are widely used without being limited thereto. One or more of these can be used. Further, in order to improve properties such as abrasion resistance, solvent resistance and adhesion to a substrate in the polishing layer, an isocyanate-based curing agent may be added to form a cured resin layer.

Further, the mechanism of action of the present invention must be studied in the future, but for the time being, the resin as a binder component in the polishing layer in the polishing film for polishing the end face of the optical fiber exhibits rubber-like elasticity when the polishing film is used, It is presumed that the polishing layer realizes buffering properties.

As the abrasive particles in the polishing layer containing a resin having a glass transition temperature of 30 ° C. or lower as a binder component, commonly used abrasive particles are appropriately used, for example, aluminum oxide, silicon carbide, silicon nitride, zirconium oxide, chromium oxide, oxidized oxide. A primary particle diameter of about 0.1 to 60 μm made of iron, diamond, boron nitride, emery, cerium oxide, or the like is used. Generally, about 100 to 1400 parts by weight of abrasive particles per 100 parts by weight of a binder component. Is a polishing layer containing.

The method for applying the coating liquid for forming a polishing layer on the base material for the polishing film includes two rolls, three rolls, a roll coat with four rolls, a gravure coat, a kiss coat, a knife coat, a bar coat, a rod coat, There are a comma coat, a spray coat, a park coat, and the like. In the roll coat method and the gravure coat method, both the direct method and the reverse method can be used, and in particular, two, three, or four reverse rolls When the coating method is used, a coating layer having excellent surface smoothness can be obtained.

In order to enhance the buffering effect of the polishing layer, the thickness of the polishing layer is preferably at least 10 μm, more preferably at least 15 μm. If the thickness is less than 10 μm, the buffer effect of the polishing layer cannot be sufficiently realized.

〔Example〕

Hereinafter, a specific configuration of the polishing film of the present invention will be described based on production examples.

Example 1 A xylylene diisocyanate [XEL curing agent (D) manufactured by Morohoshi Ink Co., Ltd.] was added to an abrasive-dispersed resin solution [A] having the following composition to prepare a polyester in the abrasive-dispersed resin [A]. The relationship between the -OH group in the resin and the isocyanate group (-NCO) of the xylylene diisocyanate to be added,
(-NCO / -OH) = 5 (equivalent ratio)
Subsequently, a coating solution having a viscosity of 85 cp obtained by diluting with an equivalent mixed solvent of toluene and methyl ethyl ketone was applied to a thickness of 50.
3 μm coated on the surface of a polishing film substrate made of a polyethylene terephthalate film by a reverse method, dried, and then subjected to an aging treatment at 45 ° C. for 7 days to a thickness of 15 μm.
By forming a polishing layer having a thickness of μm, a polishing film [i] for polishing an end face of an optical fiber, which was one embodiment of the present invention, was obtained.

In addition, the polishing film for polishing the end face of the optical fiber [i]
The glass transition temperature of the polishing layer at 11 ° C. is 11 ° C.

Abrasive dispersion resin solution [A] (1) Polyester resin ... 40 parts by weight [Toyobo Co., Ltd .: Byron # 300] (2) Aluminum oxide ... 200 parts by weight [Fujimi Abrasives: WA #] 10000] (3) Toluene 60 parts by weight (4) Methyl ethyl ketone 60 parts by weight Comparative Example 1 Polyester resin in abrasive dispersion resin solution [A] in the production process of polishing film [i] in Example 1 Polyester resin [Toyobo Co., Ltd .: Byron # 60]
0] Except that 40 parts by weight were used, the formulation was the same as in Example 1 to obtain a polishing film [ii] for comparison.

The glass transition temperature of the polishing layer in the polishing film [iii] is 46 ° C.

Comparative Example 2 Except that the thickness of the polishing layer in the production process of the polishing film [i] in Example 1 was changed to 8 μm, the formulation was the same as in Example 1 and a polishing film [iii] for comparison.
I got

Experiment Using the polishing film obtained in the above example and the polishing film for comparison, the end face of the optical fiber attached to the connector was loaded using an optical fiber end face polishing machine manufactured by Seiko Giken Co., Ltd. Final finishing polishing was performed for 30 seconds with 6 kg applied, and the reflection return loss of the obtained optical fiber was measured. As a result, the polishing finish of the optical fiber end face by the polishing film [i] was 41 dB, whereas the polishing finish by the polishing film [ii] for comparison was 37 dB, and the polishing finish by the polishing film [iii] was 39 dB.

[Functions and Effects of the Invention]

The polishing film for polishing the end face of the optical fiber of the present invention has a binder component in a polishing layer formed on a substrate for a film-like polishing film having a glass transition temperature of 30.
The resin which is used in the polishing layer as a binder component and which has a resin temperature of not more than 0 ° C. develops rubber-like elasticity when the polishing film is used, and gives the polishing layer a buffering property.

Therefore, the polishing film for polishing the end face of the optical fiber of the present invention absorbs even when an excessive pressure is applied when the film is used, so that it is affected by the surface condition of the support on the back surface of the polishing film. It is possible to carry out extremely high-precision polishing finish because there is no effect, such as being not affected by projections that are occasionally generated on the surface of the polishing film or the inclusion of foreign matter during polishing work. is there.

Claims (1)

(57) [Claims] 1. A polishing film for polishing an end face of an optical fiber comprising a polishing film substrate having a polishing layer on a film-like polishing film substrate, wherein the polishing layer has a glass transition temperature of 30 ° C. or less and a rubber-like elasticity during polishing. And a resin component having a property of realizing a buffering property in the polishing layer, and a primary particle diameter.
Comprising 0.1 to 60 μm abrasive particles, and a coating layer of a coating liquid for forming a polishing layer containing 100 to 1400 parts by weight of the abrasive particles with respect to 100 parts by weight of the resin component, A polishing film for polishing an end face of an optical fiber, wherein the polishing layer has a thickness of 10 μm or more.