The Study On The Yarn Structure And Yarn Formation Based On Solospun

Great change has taken place in spinning technology, and many unconventional spinning technologies have been invented since last century. The development of spinning technology and the research of yarn structure are reviewed in this paper. The spinning technology can be classified as ring spinning, unconventional spinning, structural and composite spinning. The history, definition and research of Sirospun, Sirofil and Solospun have also been introduced.Solospun is the latest spinning technology, which was popular in textile industry before several years ago. But now its application is not so wide as people expected. It is obvious that the technology should be recognized and improved further, so we made the research on the yarn structure and the formation mechanism. The whole experiments and results of this paper are as follows:1. The observation and photograph of the appearance of Solospun yarn and the comparison with ring-spun yarn have been conducted. It is found that the appearance of the Solospun yarn is smoother than ring-spun yarn with less hairiness. The fiber tangle in the Solospun yarn is more compact than that in the ring-spun yarn. Hence it is difficult to distinguish how many bundles in the Solospun yarn. The untwist test shows that the twist of the Solospun yarn can not be removed totally, it implies that there are weak twists in those fiber bundles.2. The break strength and abrasion resistance of Solospun yarn are higher than those of the ring-spun yarn, and the hairiness is less. But the CV (%) of the break strength and break elongation of the Solospun yarn is higher than that of the ring-spun yarn. There are more nubs and nips in the Solospun yarn than those of the ring-spun yarn, so the CV (%) of yarn evenness of the Solospun yarn is higher than that of ring-spun yarn. These results show that the quality of the Solospun yarn is not stable caused by the lost and wrong positions of the fiber bundles during Solospun spinning.3. The Solospun yarn structures are analyzed by cross-sectional Microtomy with a microtome to cut the Solospun yarn coated with collodion into pieces continuously. The thickness of the cross section piece was kept at about 20μm. To show a general view of the structural characteristics of the yarn, the trajectories of the fibersare visualized in a three-dimensional space on the basis of the data from the 45 pictures. They are theoretically helical lines. It reveals that the fiber migration is the relatively same as the ring-spun yarn. The average height of the fiber helix in the yarn is shorter than that of the fiber helix calculated by theoretical twist and the tested twist of the yarn and there exists a few self-twist, that proves the elongation at break of the Solospun yarn is higher than that of the ring spun yarn and there exists a few self-twist in the fiber bundles.4. After counting the contacted points in each slice, the probability of fibers' contact (PFC) of the Solospun yarn has been obtained and is higher than that of the ring spun yarn, but the CV of PFC is higher, too. It indicates that the beak strength of the Solospun yarn is higher than that of the ring spun yarn, but yarn evenness is worse.5. To understand the relationship between the twist of the bundle fibers and that of the yarn, we started a series of simulated spinning test were carried out. The experimental results show that the relationship between the twist of the bundle fibers and that of the yarn is affected by the spinning triangle. When the spinning triangle is 90°, the ratio between the twist of the bundle fibers and that of the yarn is highest, equal to 24.56%. When the spinning triangle approaches 0°or 180°, the ratio between the twist of the bundle fibers and that of the yarn is lowest, nearly 0, that means there is no self-twist in the bundle fibers. From the simulation spinning tests, we understand that the self-twist in the bundle fibers of Solospun yarn is very small because of the spinning triangle is too small.As a result, the key solution for Solospun spinning technology is to divide t...