JPS6261008A - Production of plastic optical fiber - Google Patents

Abstract

PURPOSE:To permit simple and inexpensive production by filling a resin for core into a tube of a plastic capillary having the inside diameter corresponding to the diameter of the core and curing the resin. CONSTITUTION:A vinyl chloride capillary, PE capillary or 'Teflon(R)' capillary is utilized as the capillary for clad and a transparent thermoplastic epoxy resin is put into the capillary with a vacuum pump by putting one end of the capillary into the resin while the transparent thermosetting epoxy resin is kept heated to 20-50 deg.C to the decreased viscosity state and connecting the other end to the vacuum pump. The resin is then cured by a hot air dryer, by which a plastic optical fiber is obtd. The capillary which can be shrunk according to the shrinkage when the resin for the core cures is used.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for manufacturing plastic optical fibers.

(Prior Art) A common method for manufacturing plastic optical fibers is to put a predetermined core resin in a container, pull it out from the tip of the n1 nozzle, heat or cool it to harden it, and then coat it with a cladding resin.

(Problems to be Solved by the Invention) In conventional manufacturing methods, adjusting the core diameter to a predetermined core diameter requires a number of factors such as resin temperature, viscosity, container pressure, nozzle management, product feed rate, tension, surrounding temperature, and cleanliness. It was necessary to control many management items such as

Therefore, sophisticated instruments are required and careful attention must be paid, which makes it expensive and disadvantageous for manufacturing a wide variety of products in small quantities.The present invention makes it possible to manufacture glass optical fibers in a very simple and inexpensive manner. The present invention provides a method.

(Means for resolving the problem) The present invention provides a plastic capillary tube having a circular diameter corresponding to the core diameter, for example, a circular diameter α1 to α2. Q + nflll,
Manufactured from thermoplastic or thermosetting resins such as vinyl chloride, polyethylene, polyethylene, Teflon, etc.If the core is made of thermosetting resin, it may be opaque, but if the core is made of thermosetting resin, it may be opaque. A transparent one is better, but the entire core resin is press-fitted into the thin tube of cIL using a compression bonder or the like. If press-fitting is difficult, the core resin can be easily inserted into the thin tube by connecting one end of the thin tube to the vacuum bong 7' and inserting the other end into the core resin container.

According to the present invention, as a method for making the core diameter constant, it is sufficient to select and use a ready-made plastic capillary whose circular diameter has a predetermined core diameter. It does not require advanced technology. Moreover, it is preferable to use an epoxy resin as the core resin in this method, but epoxy resin takes a long time to harden, and when using other plastic optical fiber core resins such as PMMA, the core resin is removed from the nozzle and cooled during spinning. Since the resin cures instantly, it is easy to spin the resin. However, since the epoxy resin takes a long time to cure, from 10 minutes to 4 hours, it has not been possible to spin the resin using conventional methods. In the present invention, even if curing takes a long time, the core resin is contained in a thin tube for cladding having a predetermined outer diameter, so the curing process can be performed regardless of the time.

The first □□□ is a cross-sectional view of a plastic optical fiber obtained according to the present invention, in which 1 is a core and 2 is a plastic tube serving as a cladding.

(Example) Using vinyl chloride tubes, polyethylene tubes, and Tenron tubes with a circular diameter of 1 mm and an outer diameter of 5 mm as cladding tubes, a vacuum pump for central testing was used to generate a vacuum pressure of 500 to 1.000 ffll.
l! Depending on Hg, the temperature of thermosetting transparent epoxy resin is 20-5
One end of the thin tube was put into the resin while keeping the temperature at 0° C. to lower the viscosity, and the other end was connected to a pump to fill the entire tube with thermosetting transparent epoxy resin. Next, when it was cured in a heat dryer for 50 minutes to 3 hours at a temperature of 100 to 200°C, a plastic optical fiber with a transmission loss of 1 to 5 dB/m could be obtained.

Note that the thin tube is preferably one that can be contracted according to the shrinkage rate of the core resin upon curing. Also, using the same method in the same thin tube, use UV curable epoxy 83/J1 to 80 W/
By resisting ultraviolet irradiation for 5 to 1 Q cm, a plastic optical fiber with similar performance can be obtained.

(Effects of the Invention) According to the present invention, the core diameter can be easily obtained, the epoxy resin can be used as a resin for all cores, which was previously impossible, and the curing method is heat treatment. Both curing and ultraviolet curing are possible, and the manufacturing process is not limited to the curing time, making it possible to manufacture plastic optical fibers extremely simply and at low cost.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of the plastic optical fiber of the present invention. μ-shape of the code 1, Far, 2. Kunihiko Wakabayashi, Patent Attorney for Plastic Tubes / Core Kou 1 Procedural Amendment (Spontaneous) Date of December 1985 Relation to Patent Application No. 201318 of 1985 Patent Applicant Address Nishi, Shinjuku-ku, Tokyo Shinjuku 2-chome 1-1 name (
445) Hitachi Chemical Co., Ltd. Representative Ryoji Yokoyama 4, Agent 163 Address Hitachi Chemical Co., Ltd., 2-1-1 Nishi-Shinjuku, Shinjuku-ku, Tokyo [Telephone: Tokyo 346-3111 <Main representative)] Specification A column for a detailed description of the invention. 6. Contents of the amendment +l) In the third and fourth lines of page 2 of the specification, the phrase "control was necessary." should be corrected to "control was necessary." (2) On page 2, line 15 of the specification tube, the word "Teflon" has been corrected to "fluorine resin." (3) On page 2, line 16 of the specification, the phrase "manufactured and the core" is corrected to "manufactured and the core is". (4) On page 4, lines 6 and 7 of the specification, "Teflon" is corrected to "fluororesin." (5) On page 4, line 17 of the specification, the phrase ``Shrinkable is best.'' should be replaced with ``Shrinkable.'' In the case of heat-shrinkable tubes, the diameter can be reduced by shrinking after heating. Make sure that the core diameter is the specified value.''that's all

Claims (1)

[Claims] 1. A method for producing a plastic optical fiber, which comprises filling a plastic thin tube with a circular diameter corresponding to the core diameter with a core resin and curing the resin.