Sumitomo Electric Industries, Limited

Nippon Telegraph and Telephone Corporation

Kazumasa Oishi

Yasuo Matsuda

Nobuhiro Akasaka

Ichiro Tsuchiya

Tatsuya Kakuta

Kaoru Okuno

Rei Koike

Akira Inoue

Atsushi Suzuki

Tomoyuki Hattori

Tetsuya Haruna

Wataru Sakurai

Kohei Kobayashi

Mitsuaki Tamura

Masahiro Takagi

Keiji Osaka

Tomomi Moriya

Yoshiji Sato

Shigeru Tomita

Kazunori Tanaka

Hideo Miyaki

Wataru Katsurashima

Tatsuo Saito

Katsuichi Omori

Yoshiharu Meguro

Kazuto Saito

Kenji Io

Yukio Nomura

When a glass fiber and an inner fiber coating layer are to be attached to a connector by removing an outer fiber coating layer while leaving the inner fiber coating layer as it is, a collective coating and the outer fiber coating layer can be removed at a stretch so that the inner fiber coating layer can easily and satisfactorily be exposed. In the ultraviolet curable resin coating layer of a coated optical fiberof an optical fiber ribbonfor wiring of equipment, the inner fiber coating layerhas a Young's modulus of 600 MPa to 1000 MPa, and the outer fiber coating layerhas a Young's modulus of 10 MPa to 300 MPa. The material of the outer fiber coating layeris made by mixing 100 weight parts of base resin, 1-30 weight parts of silicone-based additive, and 0.5 to 40 weight parts of long chain fatty acid ester compound, wherein the base resin is a material made of a urethane metha acrylate oligomer, a mono-functional or multi-functional reactive dilution monomer, and an optical initiator.

Optical fiber ribbon for wiring of equipment and connector-attached optical fiber ribbon for wiring of equipment

A molding dieis constituted by an upper dieand a lower diewhich are made of a material transparent to an ultraviolet light, and has a cavityconstituted by grooves, whereas a resin injection gateand a resin exit gateare provided so as to communicate with the cavity. A junction of an optical fiberis inserted into the cavity. A UV-curable resin is injected into the cavitysurrounding an exposing portion of the glass optical fiberfrom the resin injection gatepositioned at one of coating ends of the optical fiber, whereas a part thereof is discharged from the resin exit gatepositioned at the other coating end. The ultraviolet light is emitted through the lower dieso as to cure the resin, thereby forming a reinforcement resin coating. As a consequence, bubbles can be prevented from occurring due to the residual air within the reinforcement resin coating in the junction of the optical fiber

MOLDING APPARATUS FOR A REINFORCEMENT RESIN COATING OF GLASS OPTICAL FIBER EXPOSING PORTION OF AN OPTICAL FIBER JUNCTION, METHOD FOR MOLDING REINFORCEMENT RESIN COATING OF A GLASS OPTICAL FIBER EXPOSING PORTION OF AN OPTICAL FIBER JUNCTION, AND OPTICAL FIBER CABLE

In a method for molding an optical fiber fusion spliced portion, a mold coating is formed on a bare fiber portion of a fusion spliced portion of the optical fibers, using a resin compound having the characteristics where in a cured state, the tensile elongation is 70% or more and the tensile strength is 20MPa or more.

Method for molding optical fiber fusion spliced portion and optical fiber with molded fusion spliced portion

In an optical fiber coating method comprising the steps of; applying an injecting first coating resin to the outer periphery of the optical fiber while inserting the optical fiber through a first die hole provided in a first coating die; and applying an injected second coating resin onto the first coating resin while inserting the optical fiber through a second die hole provided in a second coating die. Wherein a disk-shaped upper end face of the second coating die and a basically disk-shaped lower end face of the first coating die having a protrusion formed around the first die hole and projecting in the passing direction of the optical fiber are opposed to each other so as to arrange the first and second die holes concentrically, and the second coating resin is injected into the second die hole by way of a gap formed between the lower end face of the first coating die and the upper end face of the second coating die, so as to reduce an annular lower-pressure region formed around the optical fiber in a flow of the second coating resin within the gap.

Optical fiber coating method and coating apparatus

In a resin coating applicator, a holder 14 is fixed on a base 15 fitted to a drawing machine, and in the holder 14, hot water can be circulated from an inlet 18. The inner circumferential surface of the holder 14 is formed into a tapered shape so that the outer circumferential surface of a cup-like member 4 of a cartridge type coating sub-assembly 1 is fitted to the holder 14. The respective outer circumferential surfaces of a nipple 2 and a coating die 3 are cylindrical so as to be fitted to the inner circumferential surfaces of an inner cylindrical member 6, and they are positioned by a step portion. Further, they are pressed from the upper and lower sides by the bottom portion of the cup-like member 4 and a lid member 5. The lid member 5 is fastened to the cup-like member 4 integrally by a thread.

Resin coating applicator for an optical fiber

Optical fiber coating method and apparatus therefor

A coated optical fiber comprising a light-transmitting fiber and a resin coating layer disposed on the outer periphery of the light-transmitting fiber is formed, an external flaw is imparted to the surface of the resin coating layer while running the coated optical fiber, and then the coated optical fiber is subjected to the measurement of a tensile breaking strength thereof. At this time, the fiber having a strength retention ratio R.sub.S =S.sub.A /S.sub.0 of 0.98 or more, wherein S.sub.A is the median value of the tensile breaking strength after the provision of the external flaw, and S.sub.0 is the median value of the tensile breaking strength before the provision of the external flaw, is selected as a non-defective product.

Coated optical fiber

Coated optical fiber and fabrication process therefor

A physical property evaluation method for optical fiber coating which is easy in producing a sample and high in accuracy and which is capable of measuring the shear modulus or tensile modulus with high accuracy, and a coated optical fiber with good lateral pressure characteristics using this evaluation method. The method comprises a step of producing a sample with the both end faces being parallel by cutting a coated optical fiber by a plane normal to the direction of the center axis of an optically transparent member, a step of holding the sample by securing the second coating layer, a step of pushing only the optically transparent member to impose a load thereon, thereby giving displacement to the optically transparent member and causing shear elastic deformation to the first coating layer, and a step of calculating the shear modulus or tensile modulus of a material forming the first coating layer, based on an amount of the displacement of the optically transparent member and a value of the load imposed thereon.

Physical property evaluation method for optical fiber coating, and

A light transmitting optical fiber having at least one coating layer of an ultraviolet curing resin on an outer surface of the fiber, in which the ultraviolet curing resin used in an outermost layer has a Young's modulus of at least 100 kg/mm.sup.2 and an elongation of at least 30%.

Light transmitting glass fiber

Growing community of inventors

Yokohama, Japan

Kazumasa Oishi