JP4504248B2 - Fiber end treatment method - Google Patents

Description

  The present invention relates to a fiber bundle in which a plurality of optical fibers used as an optical transmission body such as a light guide and an image guide provided in an endoscope, for example, and more particularly to a fiber end processing method thereof.

  Generally, in this type of fiber bundle, optical fibers formed by a plurality of cores and clads are bundled, and both end portions thereof are inserted and fixed in a base made of a metal material or a resin material. Then, an adhesive is filled between the end portions of the optical fiber and the base, and the fiber is bundled and fixed to produce a fiber bundle. As the adhesive, when the fiber bundle is disposed in the vicinity of the light source, an adhesive having a high heat resistance temperature is used by being exposed to a high temperature.

  By the way, in order to protect the optical fiber, the fiber bundle used in the endoscope forms a coating layer on at least one of fluorosilicone oil and perfluoroether on the outer periphery of the optical fiber, and a solid lubricant is formed on the coating layer. The technique which apply | coats is proposed (for example, refer patent document 1).

  However, in the technique for forming a coating layer on the outer peripheral portion, when an optical fiber bundle is used as a light guide for an endoscope, if the endoscope is subjected to high-temperature and high-pressure steam sterilization treatment, the coating layer is protected. It has the disadvantage that the effect is lost. When the protective effect by this coating layer is lost, the clad provided around the core melts at high temperature and high pressure, and the clads are fixed to each other, and the clads are fixed to each other by the bending operation of the endoscope insertion portion. There is a problem that optical transmission becomes difficult due to breakage at the site.

Therefore, a technique has been considered in which a coating layer containing a fluorine-substituted alkyl group-containing organosilicon compound is provided on the outer periphery of the optical fiber to prevent the clad from sticking to each other.
JP 2001-302286 A

  However, in the technique in which the coating layer containing the fluorine-substituted alkyl group-containing organosilicon compound is provided on the outer peripheral portion of the optical fiber, when the end portion of the optical fiber and the base are bonded and fixed using an adhesive, the coating layer has an adhesive strength between each other. When the load is applied from the outside, the fiber bundle may be depressed or pulled out from the base.

  The present invention has been made in view of the above circumstances, and a fiber end portion processing method capable of realizing reliable bonding and fixing between an optical fiber terminal portion and a base after reliably preventing adhesion between clads. The purpose is to provide.

The fiber end treatment method according to the present invention includes a first step of coating the ends of a plurality of optical fibers with a fluorine-substituted alkyl group-containing organosilicon compound and irradiating each coating layer with plasma, and irradiating the plasma. and by bundling coating layer of a plurality of optical fibers bonded with adhesives, it has configured and a second step of producing a fiber bundle.

  According to the above configuration, the terminal portions of the plurality of optical fibers coated with the fluorine-substituted alkyl group-containing organosilicon compound are bonded to the C radicals of the organic pollutant and fluorine-substituted alkyl group organosilicon compound by oxidation radicals generated by the plasma state. By cutting and oxidative decomposition, it is removed in the state of carbon dioxide, and a functional group containing oxygen is formed on the surface, and it is bundled and bonded and fixed in a state where a molecular level uneven surface is formed. As a result, the coated fluorine-containing alkyl group-containing organosilicon compound reliably prevents the clad of the optical fibers from sticking to each other, and the plasma treatment causes organic contaminants and fluorine-substituted alkyl group organosilicon compounds to be decomposed and removed. The uneven surface of the optical fiber enhances the adhesive strength of each end portion of the optical fiber, and secures the adhesive bonding.

Further, the fiber end treatment method of the present invention includes a first step in which a fluorine-substituted alkyl group-containing organosilicon compound is coated on end portions of a plurality of optical fibers , and each coating layer is irradiated with plasma, and the plasma And a second step of manufacturing a fiber bundle by bundling a plurality of optical fiber coating layers irradiated with the above and inserting the same into a base and filling an adhesive.

  According to the above configuration, the terminal portions of the plurality of optical fibers coated with the fluorine-substituted alkyl group-containing organosilicon compound are bonded to the C radicals of the organic pollutant and fluorine-substituted alkyl group organosilicon compound by oxidation radicals generated by the plasma state. By cutting and oxidative decomposition, it is removed in the state of carbon dioxide, and a functional group containing oxygen is formed on the surface, and a molecular level uneven surface is formed and bundled and inserted into the base and bonded and fixed. The As a result, the coated fluorine-containing alkyl group-containing organosilicon compound reliably prevents the optical fiber clads from sticking to each other, and the organic contamination and fluorine-substituted alkyl group organosilicon compound are decomposed and removed by the plasma treatment. The uneven surface of the optical fiber enhances the adhesive strength of each end portion of the optical fiber, and secures adhesive bonding within the base.

  As described above, according to the present invention, there is provided a fiber end portion processing method capable of realizing reliable bonding and fixing between an optical fiber terminal portion and a base after reliably preventing adhesion between clads. be able to.

  Hereinafter, a fiber end processing method according to an embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 1 shows a terminal portion of a fiber bundle 10 manufactured by a fiber end processing method according to an embodiment of the present invention. The terminal portions of a plurality of optical fibers 11 are inserted into a base 12. Filled with an adhesive. That is, the plurality of optical fibers 11 are formed by the core 111 and the clad 112 as shown in FIG. 2, and the coating layer 13 is formed on the outer peripheral portion of the terminal portion, which is coated with the fluorine-substituted alkyl group-containing organosilicon compound. The plurality of optical fibers 11 covered with the coating layer 13 are transferred to the plasma processing step, and for example, as shown in FIG. 3, the optical axes are arranged in parallel on a plane and the coating layers are arranged. The end face on the terminal portion side from which 13 is removed is aligned and disposed opposite to the plasma generator 14.

  The plasma generator 14 generates plasma particles in the atmosphere and irradiates plasma onto the coating layers 13 at the end portions of the plurality of optical fibers 11 (see FIG. 4). This plasma treatment is performed, for example, in a range of 5 to 100 mm at the end portion of the optical fiber 11, and is performed by moving and scanning the plasma generator 14 in the front-rear direction and the left-right direction.

  Next, in the grad assembly process, the plurality of optical fibers 11 are filled with a terminal portion subjected to plasma treatment on the coating layer 13 with an adhesive interposed in the base 12 (see FIG. 1). It is formed. Here, the coating layers 13 of the plurality of optical fibers 11 are removed in the state of carbon dioxide by separating and oxidizing organic C molecules by the plasma irradiated by the plasma treatment. At the same time, the irradiated plasma forms a functional group containing oxygen on the surface of the coating layer 13, and further forms an uneven surface at the molecular level.

  Thereby, the plurality of optical fibers 11 are experimentally filled with the base 12 by increasing the adhesive force between the coating layer 13 and the adhesive, and the coating layer 13 prevents mutual clad 112 from sticking to each other. Is confirmed.

  Here, the plasma irradiation conditions of the plasma generator 14 during the experiment were, for example, that the supply gas composition was formed of argon and oxygen, and the plasma type was oxygen plasma. The argon gas flow rate can be set in the range of 1.0 to 5.0 L / mm, and the oxygen gas flow rate can be set in the range of 10 to 50 cc / min. Preferably, the argon gas flow rate is 1.5 to 2.5 L / mm, and the oxygen gas flow rate is 20 to 30 cc / min. Moreover, the space | interval of the terminal part of the optical fiber 11 from the plasma generator 14 is possible in the range of 1.0 mm-50 mm.

  The above conditions are obtained by measuring the fiber terminal portion adhesive force when the plasma output from the plasma generator 14 is constant and the scanning speed of the plasma spot is moved in 5 mm increments between 5 and 20 mm / sec.

  Here, experimentally, when the distance from the plasma generation device 14 to the end portion of the optical fiber 11 is 5 mm and 10 mm, a result that both are very good at a scanning speed of 5 mm / sec as shown in FIG. 5 is obtained. When the scanning speed is 10 mm / sec and the distance is 5 mm, a very good result is obtained. When the distance is 10 mm, the good result is obtained. When the scanning speed is 15 mm / sec, the distance is 5 mm. A result is obtained, a result that is slightly better when the distance is 10 mm, a result that is better when the distance is 5 mm at a scanning speed of 20 mm / sec, and a result that is slightly better when the distance is 10 mm is obtained. In the absence of plasma treatment, it is confirmed that there is no improvement in adhesion.

  As described above, the fiber end treatment method irradiates each of the terminal portions of the plurality of optical fibers 11 provided with the coating layer 13 coated with the fluorine-substituted alkyl group-containing organosilicon compound, and then irradiates the plasma. The end portion of the optical fiber 11 was bundled and inserted into the base 12 and filled with an adhesive, so that the fiber bundle 10 was manufactured.

  According to this, the terminal part of the some optical fiber 11 which has the coating layer 13 which coat | covered the fluorine-substituted alkyl group containing organosilicon compound isolate | separates C molecule | numerator of organic substance with plasma, and oxidizes, The state of a carbon dioxide In addition, a functional group containing oxygen is formed on the surface, and a molecular level uneven surface is formed and bundled and inserted into the base 12 and bonded and fixed. As a result, the adhesion between the clads of the optical fiber 11 is reliably prevented, and the adhesion of each end portion of the optical fiber 11 is enhanced by the uneven surface of the molecular level from which the carbon dioxide formed by the plasma treatment is removed. Then, reliable bonding and fixing within the base 12 is performed.

  In the above embodiment, the case where the fiber bundle 10 is manufactured by bonding and fixing the plurality of optical fibers 11 in the base 12 has been described. However, the present invention is not limited to this, and the base 12 is not used. It is also possible to manufacture the fiber bundle by bonding and fixing the terminal portions of the plurality of optical fibers 11.

  In the above-described embodiment, the case where the atmospheric pressure plasma is applied to the coating layer of the end portion of the optical fiber 11 as the plasma irradiation has been described. However, the present invention is not limited to this, and other than that, reduced pressure plasma, air plasma, etc. It is also possible to configure so that the same effect is expected.

  Therefore, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention at the stage of implementation. Further, the above embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements.

  For example, even if some constituent elements are deleted from all the constituent elements shown in the embodiment, the problem described in the column of the problem to be solved by the invention can be solved, and the effect described in the effect of the invention can be obtained. In some cases, a configuration from which this configuration requirement is deleted can be extracted as an invention.

  In addition, according to each of the above embodiments, the present invention can also obtain the following configuration.

(Appendix 1)
A method for producing a fiber bundle in which a plurality of optical fibers coated with a fluorine-substituted alkyl group-containing organosilicon compound are bundled,
A fiber end processing method, wherein after irradiating plasma to the terminal portions of each of the plurality of optical fibers, the fiber bundles are manufactured by bundling the optical fibers and bonding the terminal portions.

(Appendix 2)
A method for producing a fiber bundle in which a plurality of optical fibers coated with a fluorine-substituted alkyl group-containing organosilicon compound are bundled,
A fiber end treatment method comprising manufacturing the fiber bundle by irradiating each of the plurality of optical fibers with plasma, bundling the optical fibers, inserting the optical fibers into a base, and filling the adhesive.

(Appendix 3)
The fiber end treatment method according to appendix 1 or 2, characterized in that the plasma irradiation conditions are: the supply gas composition is argon and oxygen, and the plasma type is oxygen plasma.

(Appendix 4)
The fiber end treatment method according to appendix 3, wherein the plasma irradiation conditions are: the argon gas flow rate is 1.0 to 5.0 L / min, and the oxygen gas amount is 10 to 50 cc / min.

(Appendix 5)
The fiber end treatment method according to appendix 3 or 4, wherein the plasma irradiation condition is that the distance from the plasma generator to the end of the optical fiber is 1.0 mm to 50 mm.

It is the figure which showed the terminal part structure of the fiber bundle manufactured by the fiber end part processing method concerning one embodiment of this invention. It is the figure which showed the structure of the optical fiber of FIG. It is the figure which showed the plasma treatment process. It is the figure which showed the plasma irradiation state of FIG. It is the figure which showed the example of plasma irradiation conditions of the fiber bundle manufactured by FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Fiber bundle, 11 ... Optical fiber, 111 ... Core, 112 ... Cladding, 12 ... Base, 13 ... Covering layer, 14 ... Plasma generator.

Claims (5)

A first step of coating a fluorine-substituted alkyl group-containing organosilicon compound on the terminal portions of a plurality of optical fibers, and irradiating plasma on each coating layer;
A second step of manufacturing a fiber bundle by bundling a plurality of optical fiber coating layers irradiated with the plasma and bonding them with an adhesive;
A fiber end treatment method comprising: A first step of coating a fluorine-substituted alkyl group-containing organosilicon compound on the terminal portions of a plurality of optical fibers, and irradiating plasma on each coating layer;
A second step of manufacturing a fiber bundle by bundling a plurality of optical fiber coating layers irradiated with the plasma, inserting the bundle into a base, and filling an adhesive;
A fiber end treatment method comprising:   The fiber end treatment method according to claim 1 or 2, wherein the plasma irradiation conditions in the first step are: the supply gas composition is composed of argon and oxygen, and the type of plasma is oxygen plasma.   4. The fiber end treatment method according to claim 3, wherein the plasma irradiation condition is that the argon gas flow rate is 1.0 to 5.0 L / min and the oxygen gas amount is 10 to 50 cc / min. 5. The fiber end treatment method according to claim 3, wherein the plasma irradiation condition is that the distance from the plasma generator to the coating layer of the optical fiber is 1.0 mm to 50 mm.

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