Blended fabrics are textile products made of chemical fibers mixed with other natural fibers such as cotton, silk, linen and other natural fibers. They have the style of polyester and the advantages of cotton fabrics, such as polyester-cotton cloth, polyester-wool gabardine, etc. Blended fabrics are divided into wool-viscose blended fabrics, sheep and rabbit fur velvet fabrics, TR fabrics, high-density NC fabrics, 3M waterproof mousse fabrics, Tencel (TENCEL) fabrics, Rousey silk, TNC fabrics, composite fabrics, etc.
For example, polyester-cotton blends use polyester as the main component, using 65%-67% polyester and Textile made of 33%-35% cotton mixed yarn, polyester-cotton cloth is commonly known as cotton.
This article briefly introduces the dyeing of synthetic fiber blended knitted fabrics
1 , Dyeing methods and precautions for blended knitted fabrics
1. Blended knitted fabrics: knitted fabrics made by mixing and spinning two or more different fibers and then knitting them.
1.1 Interwoven knitted fabric: a knitted fabric made of two kinds of yarns (different fibers) or two kinds of filaments knitted alternately.
1.2 Multi-color effect: In the dyeing of mixed yarn knitted fabrics, different colors are required.
1.3 White space effect: requiring one fiber to be dyed while another fiber is required to avoid dyeing.
2. Dyeing method of mixed yarn knitted fabrics
2.1 Same as One-step bath method: one or two dyes with different properties are used to dye different fibers at the same time in the same dye bath.
2.2 Two-step method in the same bath: that is, first dye one fiber with one dye, then add another dye to this bath and use another process set Dye another fiber. In this dyeing method, it is required that the residual liquid from the first dyeing step has no adverse effect on the second dyeing step.
2.3 Two-bath two-step method: first prepare a dye bath with one dye to dye one fiber, empty the remaining bath, and then prepare a second bath for the second Fiber dyeing.
2.4 The dyeing method used should be based on the composition, properties and blending ratio of the fibers in the mixed fabric, as well as the types and properties of optional dyes and auxiliaries, and the dyeing depth. and product quality requirements.
3. Precautions for dyeing blended and interwoven fabrics
3.1 The selection principles of dyes are:
a. The color development effect of a dye in different fibers, the dyeing rate, the dyeing saturation amount, and whether the fastness is close.
b. If there are two types of dyes, the following points should be paid attention to:
① Prevent precipitation (for cationic and acidic dyes, add anti-settling agent)
② Prevent contamination (for example, dye polyester-nitrile interwoven fabrics with one-bath dyeing method)
③ Must have similar fastness
3.2 Dyeing temperature: The dyes selected in one-bath one-step dyeing should preferably have similar temperature rise and dyeing rate curves.
3.3 Dyeing PH value
3.4 Effect of auxiliaries
2. Dyeing process of synthetic fiber blended or interwoven knitted fabrics
1. Polyester-cotton interwoven knitted fabrics Dyeing of objects
1.1 Disperse dyes, reactive dyes and direct dyes are dyed in one step in the same bath. A carrier is added to the dye bath to make the disperse dye dye polyester. This method has fastness Poor.
1.2 In actual production, the two-bath dyeing method is mostly used. The two-bath method is to dye polyester with high temperature and high pressure first, then use reactive dyes, and dye cotton in another bath. In order to make the dyed product bright in color, reduction cleaning can be performed after the first bath to remove the disperse dye stained on the cotton fiber. However, reactive dyes must be fixed in an alkaline bath, which often affects the color light or color depth of disperse dyes.
2. Dyeing of polyester/acrylic mixed yarn or interwoven knitted fabrics
2.1 Disperse dyes cannot be used and dyed in one step in the same bath. The reason is that the dye uptake rates are too different and color matching is more difficult.
2.2 Disperse dyes and cationic dyes are dyed in the same bath in one step, using wintergreen oil as a carrier. The disadvantages are that acrylic fiber is easy to shrink, and cationic dyes are easy to precipitate with the diffusing agent in disperse dyes.
2.3 It is best to use the two-step dyeing method in the same bath or the two-bath method. Polyester should be dyed using high temperature and high pressure and then overdyed acrylic with cationic dyes in a second bath. Finally, soft treatment. Polyester must be thoroughly restored and cleaned after dyeing, otherwise contamination with cationic dyes will affect the rubbing fastness.
2.4 Dyeing of polyester-nylon interwoven knitted fabrics. When dyeing the same color, attention should be paid to disperse dyes, which may show different colors on different fibers.
2.5 Most products for dyeing acrylic-cotton mixed yarn or interwoven knitted fabrics only require dyeing acrylic fiber and not cotton fiber, that is, leaving blank products. At this time, disperse dyes can be used to dye light colors, and cationic dyes can be used to dye dark colors. If the cotton quilt is stained, cleaning can be strengthened. Sometimes in order to improve the brightness of the product, the cotton can be bleached first and then dyed. If double-dyed, cotton should be dyed first and then acrylic. </p
