Patent ID: 7887728
Filing Date: 2011-02-15
Classification: D01D

Abstract:
1. A spinning pack for semi-wet spinning, comprising a spinneret housing, a raw spinning solution passage formed inside the spinneret housing, a raw spinning solution feed port formed in the spinneret housing, for feeding the raw spinning solution into the raw spinning solution passage, and a spinneret installed in the spinneret housing and having numerous spinning holes arranged at intervals for discharging the raw spinning solution of the raw spinning solution passage, wherein the outer surface of the spinneret faces the liquid surface of a coagulating liquid through a gas phase, and wherein the number of the spinning holes is 6,000 or more and the aspect ratio Ra of an array of the spinning holes is 2.5 or more, wherein the aspect ratio Ra is defined with the formula Ra=A 2 /B 2 , where B 2 is a length of a shortest line segment among line segments obtained when straight lines passing a center of a spinneret surface cross the spinning hole region and A 2 is a length of a longest line segment among line segments obtained when straight lines perpendicular to the shortest line segment cross the spinning hole region, and wherein the spinning hole region is a face surrounded by an envelope drawn by connecting the spinning holes located on the outermost side of the spinning hole array among the numerous spinning holes arranged in the spinneret surface, wherein the numerous spinning holes are classified into at least two spinning hole groups on a surface of the spinneret, and a spinning hole-free zone free from spinning holes is provided between the spinning hole groups, wherein the width of the spinning hole-free zone is the shortest distance between spinning holes of adjacent spinning hole groups and is greater than the distance between adjacent spinning holes in the spinning hole groups.