The Furukawa Electric Co., Ltd.

Nippon Telegraph and Telephone Corporation

Okano Electric Wire Co., Ltd.

Nobuhisa Ishii

Masao Tachikura

Hisashi Izumita

Shigenori Uruno

Eiji Konda

Fuminori Nakajima

Hitoshi Ishimaru

Ryuichi Matsuoka

Kuniaki Yamaguchi

Toru Wakita

Eizi Konda

An optical fiber cord which is a single core optical fiber cord having an outer diameter of 1.2 mm or less, and has a structure in which an optical fiber core wire having a resin coating is provided at the center, a tensile-strength-fiber layer is provided around the outer periphery of the optical fiber core wire, and a coating layer is further provided around the outer periphery of the tensile-strength-fiber layer, wherein the coating layer is composed of a non-halogen fire-retardant resin, is disclosed. This optical fiber cord has excellent fire retardant, mechanical and handling properties, although the outer diameter thereof is made smaller.

Optical fiber cord

A single core optical fiber cord having an outer diameter of 1.2 mm or less, and having a structure in which an optical fiber core wire having a resin coating provided at the center, a tensile-strength-fiber layer around the periphery of the optical fiber core wire, and a coating layer around the outer periphery of the tensile-strength-fiber layer is provided. The coating layer can be composed of a non-halogen fire-retardant resin. The optical fiber cord has excellent fire retardant, mechanical and handling properties, although the outer diameter thereof is 1.2 mm or less.

An optical fiber cable comprises a slender base body having spiral grooves formed on the outer circumferential surface, and at least one optical fiber tape housed within each of said grooves, said tape including a plurality of insulated optical fibers and a resin coating layer covering said optical fibers. The base body is formed of a mixture of at least two materials differing from each other in the molecular weight distribution. The particular construction permits markedly suppressing an increase of transmission loss derived from micro-bend occurring in the optical fiber tape arranged within the base body, and also permits arranging optical fiber tapes within the base body at a higher density.

Optical fiber cable

In a flame-retardant coated optical fiber, which comprises an optical fiber, a primary coating layer covering the optical fiber, and a secondary coating layer covering the primary coating layer, the primary coating layer is made of an ultraviolet-curing resin, and the secondary coating layer is made of a resin composition containing 20 to 70 parts by weight of ethylene-bis-tetrabromophthalimide and 5 to 40 parts by weight of antimony trioxide, based on 100 parts by weight of thermoplastic polyester elastomer. The secondary coating layer of the coated optical fiber has high flame retardancy which is in conformity to the UL standard, and the bonding strength between the primary and secondary coating layers is high enough. Thus, a projection of the optical fiber during actual use is too small to damage a light source.

Flame-retardant coated optical fiber

Growing community of inventors

Chiba, Japan

Nobuhisa Ishii