Nylon fabric needs to be washed before the nylon fabric is set

Normally dyed nylon fabric containing spandex needs to be washed before setting, because the content of spandex is high, and the relative amount of silicon lubricating oil contained is high (the amount of silicon oil contained in spandex generally can reach more than 8%). If the silicone oil is not removed before the embryo is fixed, When the high temperature embryo is timed, the silicone oil will be cross-linked and adsorbed on the nylon yarn, which will seriously hinder the dyeing of the acid material during dyeing, thereby forming dyed flowers.

a. Generally, dry cleaning machine (tetrachloroethylene as extractant) is used for airtight oil removal. This is a better method, and the removal efficiency of silicone oil is high; however, this additive is toxic and has been banned for environmental protection reasons.

b. Second, an open-width washing machine will be used, the number of sections of the feeding box and the washing box can be adjusted, degreasing agent and chelating dispersant can be added, overflow drainage is required for each tank, and the total water consumption is controlled at 1:40-1 : 60, the general degreasing efficiency is only 30%-40%, but it can make the oil content of the cloth more evenly distributed and improve the dyeing. It is very important to pay attention to the selection of degreasing agent and dispersant to prevent the washed silicone oil from demulsification and re-staining, dyeing white spots are formed.

c. Third, the dyeing factory limited by the conditions will use the Beam tank or the JET tank to remove oil first (including some indeterminate embryos, directly drop the tank for oil removal and dyeing), the oil removal efficiency will be higher, but it should be noted that the cloth In the case of no pre-shrinking, the cloth can be directly removed from the dyeing tank to remove oil. After dyeing, creases and chicken feet will easily appear on the cloth surface. Degreasing.

d. Some developed varieties need to be pre-shrunk and pre-treated in order to achieve specification requirements or cloth surface effects.

2. High temperature scheduled embryos will affect the dyeing
Nylon fabric, under high temperature conditions, the terminal amino group is very easy to be oxidized (acidic material color group). Nylon high temperature anti-yellowing agent must be added.

It is worth mentioning the problem of yarn separation after purchase. We found that often after a batch of yarns came back, there would always be one or two yarns that were colored differently from other yarns, including Korean Hyosung, Asahi Kasei, Toray and DuPont yarns. In the early stage of bulk weaving, it is necessary to test yarns to separate yellow and white yarns and dark and light yarns. Because of the slight difference in color absorption of these yarns, when the embryo is fixed at high temperature, it will appear horizontal and straight in the final dyeing like triode enlargement.

At the same time, the storage conditions of the yarn count will also cause the difference in color absorption of the nylon yarn, so the storage environment of the nylon yarn is very important.