申请人:Kojima Junichi
公开号:US20100184347A1
公开(公告)日:2010-07-22
An object of the present invention is to provide polyurethane elastic fibers that, when dyed with acidic dyes, exhibit a deep dyeing property and high fastness equivalent to those of polyamide fibers used as a companion material in mixed knitted and woven fabrics, while also exhibiting excellent spinning stability.
The inventive polyurethane elastic fibers comprise 0.2 wt %-10 wt % of a polymer with a maleimide structure comprising an isobutylene unit represented by the following formula (I) and a maleimide unit represented by the following formula (II) (wherein R
1
represents a C
2-6
straight-chain or branched alkylene group, and R
2
and R
3
may be the same or different and each represents a C
1-6
straight-chain or branched alkyl group), have a Blue L value of 20-50 after laundering according to JIS L0844 A2 for dyeing of a single-loop tube-knit fabric with a specific blue acidic dye, and have a staining degree of grade 3.5 or greater on nylon fabrics.