Abstract: A sea-island composite fiber includes island component fibers having a circumscribed circle diameter of 10 to 1000 nm, a circumscribed circle diameter variation of 1 to 20%, a non-circularity of 1.2 to 5.0, and a non-circularity variation of 1 to 10%.

Abstract: A sea-island composite fiber includes island component fibers having a circumscribed circle diameter of 10 to 1000 nm, a circumscribed circle diameter variation of 1 to 20%, a non-circularity of 1.2 to 5.0, and a non-circularity variation of 1 to 10%.

Abstract: A composite spinneret for discharging a composite polymer stream consisting of at least two or more component polymers, which includes a metering plate having multiple metering holes for metering respective component polymers, a distribution plate with multiple distribution holes formed in the distribution grooves for joining the polymer streams discharged from the metering holes, and a discharge plate.

Abstract: A sea-island composite fiber has an island component which is ultrafine fibers having a noncircular cross-section, the ultrafine fibers being uniform in the degree of non-circularity and in the diameter of the circumscribed circle. The sea-island composite fiber includes an easily soluble polymer as the sea component and a sparingly soluble polymer as the island component, and the island component has a circumscribed-circle diameter of 10-1,000 nm, a dispersion in circumscribed-circle diameter of 1-20%, a degree of non-circularity of 1.2-5.0, and a dispersion in the degree of non-circularity of 1-10%.

Abstract: A sea-island composite fiber has an island component which is ultrafine fibers having a noncircular cross-section, the ultrafine fibers being uniform in the degree of non-circularity and in the diameter of the circumscribed circle. The sea-island composite fiber includes an easily soluble polymer as the sea component and a sparingly soluble polymer as the island component, and the island component has a circumscribed-circle diameter of 10-1,000 nm, a dispersion in circumscribed-circle diameter of 1-20%, a degree of non-circularity of 1.2-5.0, and a dispersion in the degree of non-circularity of 1-10%.

Abstract: By using carbon fibers having a fineness of 25,000 deniers or more, the present invention provides a carbon fiber package including a cheese winding package or a coreless package in which an outside diameter of the package, a diameter of a bobbin or an inside diameter of the package, and a winding width are regulated in the specific ranges, a square-end type package in which a yarn width per fineness, wind angles at the start of winding and at the end of winding, and shifting of the yarn are regulated in the specific ranges, and a carbon fiber packed member in which an average bulk density is regulated in a specific range. Those carbon fiber packages and the carbon fiber packed member solve troubles and inconveniences during use, and also packages which have a high winding density and which do not break easily can be obtained.

Abstract: A method of lining a channel can be provided which includes the steps of: installing at a work site a roll having wound thereon a rigid or semirigid plastic pipe shaped initially in the form of an approximately round tube and deformed from the initial form to a flat tubular form, paying off the pipe as softened by heating from the roll installed at the work site toward an inlet of the channel to be lined, and folding the paid-off flat pipe in two to a U shape at a position between the roll and the channel inlet. The U-shaped pipe is hardened by forced cooling from outside immediately after the folding step while being restricted in shape, then inserted into the channel while being thus hardened and thereafter restored to the initial form by being inflated with heat and pressure applied from inside, whereby a lining of improved quality can be formed with an improved work efficiency.

Abstract: A running apparatus within a pipe runs such that a center axis of a main body of the running apparatus is automatically coincided with a center axis of the pipe during running, and smoothly runs within a curved pipe.