JP2000062057A - Plastic tube composite - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a plastic tube composite useful for the outer skin of an image fiber. SOLUTION: This composite is used for the outer skin of an image fiber and is a plastic tube composite, which is produced by providing a tube layer 2 or 3, in which no material such as carbon powders or the like as the main cause of the lowering of characteristics is added, on at least one side of the inside or outside of a base tube, to which a material such as carbon powders or the like as the main cause of the lowering of the characteristics is added. The desired buckling resistance and coloration are obtained by the base tube 1 and, at the same time, a favorable slipperiness is obtained by the tube layer 2 or 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plastic tube composite useful as an outer cover of an image fiber composed of an assembly of optical fibers.

[0002]

2. Description of the Related Art An outer sheath of an image fiber is usually provided with a polyimide tube. In manufacturing the polyimide tube, for example, a polyimide varnish is applied in a longitudinal direction on a round wire having an outer diameter, and after baking, It is formed by pulling out the round wire.

This polyimide tube is required to have good slipperiness so that the image fiber can be smoothly inserted, and at the same time, it is required to have resistance to cavities that is hard to be deformed by a pressure in the longitudinal direction, and at the same time, to be light-resistant. In order to prevent light leakage from the fiber, coloring of the tube such as black is required. In order to improve the resistance to cavities and coloring, carbon is generally added to a resin material such as polyimide.

[0004]

However, when a material such as carbon is added in this way, there is a problem that the surface of the tube becomes rough in the case of a polyimide tube or the like. The graininess tends to appear remarkably when a large amount of carbon or the like is added or when the dispersion is poor. Therefore, it is desirable to suppress the addition amount of the material such as carbon as small as possible, but it is rarely required to add the material such as a large amount of carbon in order to improve the above-mentioned cavitation resistance. There wasn't. If the tube surface, especially the inner surface, becomes rough due to the addition of a large amount of carbon and other materials, the image fiber will not be inserted smoothly when it is used as the outer tube of the image fiber, leading to a decrease in workability. There is a risk that the optical fiber itself may be damaged and the yield may be reduced. In addition, in the case where the outer surface is rough, there is a problem that the slipperiness during use of the product is poor and the usability is reduced.

The present invention has been made in view of the above-mentioned conventional problems, and a base made by adding a material such as carbon, that is, a material that causes deterioration of characteristics, to the cavitation resistance and coloring. For the good slidability, etc., the tube is loaded with the material, and the material which is a factor that deteriorates the properties provided in the inner layer and / or the outer layer of the base tube is loaded on the tube layer without addition, and the above conventional problems are solved. It is intended to provide a plastic tube composite.

[0006]

According to a first aspect of the present invention, the material causing the characteristic deterioration is not added to at least one of the inside and the outside of the base tube to which the material causing the characteristic deterioration is added. The plastic tube composite is characterized in that it is provided with a tube layer.

The present invention according to claim 2 is for an outer cover of an image fiber composed of an assembly of optical fibers, and is provided on at least one of the inside and outside of a base tube to which a material that causes deterioration of characteristics is added. A plastic tube composite is characterized in that a tube layer containing no additive is provided as a material that causes deterioration of characteristics.

The present invention according to claim 3 is the plastic tube composite according to claim 1 or 2, characterized in that the base tube and the tube layer are made of polyimide as the plastic.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an example of an embodiment of a plastic tube composite body according to the present invention. In the figure, 1 is a base tube, 2 is a tube layer provided on the inner surface side, 3 is a tube layer provided on the outer surface side, 4
Is an image fiber composed of an assembly of optical fibers inserted in the base tube 1.

The base tube 1 is formed by adding about 3 to 10 parts by weight of carbon to 100 parts by weight of a base resin such as polyimide. The addition of this relatively large amount of carbon improves cavitation resistance on the side of the base tube and provides desired coloring (blackening), but the tube surface becomes rough. Therefore, carbon can be regarded as a material that causes deterioration of the characteristics from the viewpoint of appearance characteristics on the base tube 1 side.

The inner and outer tube layers 2 and 3 of the base tube 1 are provided exclusively for improving slipperiness and the like, and are made of a natural resin such as polyimide.
That is, the base tube 1 is made of a resin in which a material such as carbon that causes a deterioration in characteristics is not added.

In the production of such a plastic tube composite, for example, an enameled wire baking machine is used to apply a paint on the ceramic electric wire, and after baking, the ceramic electric wire of the core is pulled out. For example, when the thickness of the base tube 1 side is about 30 μm, the thickness of the tube layers 2 and 3 may be 1 μm or more, and more preferably 3 μm or more. That is, when the thickness is 3 μm or more, roughness due to unevenness on the base tube 1 side is favorably smoothed, and smooth slipperiness can be obtained.

EXAMPLES Plastic tube composites satisfying the conditions of the present invention (Examples 1 to 3), plastic tube composites lacking the conditions of the present invention (Comparative Examples 1 to 2), and tubes without inner and outer tube layers ( Comparative Examples 3 to 4) were produced, and their cave resistance, coloration, and slipperiness were examined. The results are shown in Table 1. In addition, in the same table, the anti-cave property is examined by the kink diameter (for example, the diameter of the ring when the ring is broken by making a ring by hand and making it smaller),
The coloring was visually examined, and the slidability was examined by the insertability into a Teflon tube having an outer diameter of +5 μm. Then, it is indicated as ◯ when it is good, as Δ when it is somewhat good, and as x when it is bad.

[0014]

[Table 1]

From Table 1, in the case of the plastic tube composites (Examples 1 to 3) satisfying the conditions of the present invention, desired cavitation resistance and coloring, and good sliding property can be obtained. I understand. On the other hand, plastic tube composites lacking the conditions of the present invention (Comparative Examples 1-2) and tubes without inner and outer tube layers (Comparative Examples 3-4).
It can be seen that in the case of the above, the desired cave resistance and coloring were not obtained, and good slipperiness was not obtained.

[0016]

EFFECT OF THE INVENTION According to the plastic tube composite of the present invention, the desired cavitation resistance and coloring can be achieved by using the base tube to which the material such as carbon, that is, the material that causes the deterioration of the characteristics is added. In addition to obtaining the same, good slipperiness and the like can be provided as an excellent tube composite because a material that is a factor for deteriorating the properties provided in the inner layer and / or the outer layer of the base tube can be obtained by the tube layer without addition. . In particular, when the tube for the outer cover of the image fiber is used, the insertion of the image fiber can be smoothly performed and the workability can be expected to be improved. Moreover, the damage to the optical fiber itself can be prevented, so that the yield can be improved. it can. Further, since the roughness on the outer surface side of the tube is also improved, the slipperiness during use of the product is good and good usability can be obtained.

[Brief description of drawings]

FIG. 1 is a plastic tube composite 1 according to the present invention.
It is a longitudinal cross-sectional view showing one embodiment.

[Explanation of symbols]

1 base tube 2,3 tube layers 4 image fiber

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 2H001 DD23 KK12 KK22 MM08                 4F100 AA37B AK49A AK49B AK49C                       AR00D BA02 BA03 BA04                       BA06 BA07 BA10A BA10D                       BA41 DA02 DD32 EJ91A                       EJ91C GB90 JK01 JK16                       JL10 JN08 JN08D

Claims (3)

[Claims] 1. A plastic tube characterized in that a tube layer containing no addition of the material causing the characteristic deterioration is provided on at least one of the inside and outside of the base tube to which the material causing the characteristic deterioration is added. Complex. 2. A material for causing a deterioration of characteristics on at least one of the inside and outside of a base tube, which is used for the outer cover of an image fiber formed of an aggregate of optical fibers and to which a material causing a deterioration of characteristics is added. A plastic tube composite characterized by being provided with an additive-free tube layer. 3. The plastic tube composite according to claim 1, wherein the base tube and the tube layer are made of polyimide as a plastic.